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Sample records for ghz digital signal

  1. Analysis of pulse-shape discrimination techniques for BC501A using GHz digital signal processing

    International Nuclear Information System (INIS)

    Rooney, B.D.; Dinwiddie, D.R.; Nelson, M.A.; Rawool-Sullivan, Mohini W.

    2001-01-01

    A comparison study of pulse-shape analysis techniques was conducted for a BC501A scintillator using digital signal processing (DSP). In this study, output signals from a preamplifier were input directly into a 1 GHz analog-to-digital converter. The digitized data obtained with this method was post-processed for both pulse-height and pulse-shape information. Several different analysis techniques were evaluated for neutron and gamma-ray pulse-shape discrimination. It was surprising that one of the simplest and fastest techniques resulted in some of the best pulse-shape discrimination results. This technique, referred to here as the Integral Ratio technique, was able to effectively process several thousand detector pulses per second. This paper presents the results and findings of this study for various pulse-shape analysis techniques with digitized detector signals.

  2. Digital coherent detection of multi-gigabit 40 GHz carrier frequency radio-over-fibre signals using photonic downconversion

    DEFF Research Database (Denmark)

    Caballero Jambrina, Antonio; Zibar, Darko; Tafur Monroy, Idelfonso

    2010-01-01

    Detection of high-speed radio signals is a challenge for next generation radio-over-fibre links, requiring high bandwidth and linearity in the receiver. By using photonic downconversion in a coherent receiver, detection of high bit-rate 16-QAM signals, up to 4 Gbit/s, at a 40 GHz carrier frequency...

  3. Characterization of a 300-GHz Transmission System for Digital Communications

    Science.gov (United States)

    Hudlička, Martin; Salhi, Mohammed; Kleine-Ostmann, Thomas; Schrader, Thorsten

    2017-08-01

    The paper presents the characterization of a 300-GHz transmission system for modern digital communications. The quality of the modulated signal at the output of the system (error vector magnitude, EVM) is measured using a vector signal analyzer. A method using a digital real-time oscilloscope and consecutive mathematical processing in a computer is shown for analysis of signals with bandwidths exceeding that of state-of-the-art vector signal analyzers. The uncertainty of EVM measured using the real-time oscilloscope is open to analysis. Behaviour of the 300-GHz transmission system is studied with respect to various modulation schemes and different signal symbol rates.

  4. Digital coherent detection of multi-gigabit 40 GHz carrier frequency radio-over-fiber signals using photonic downconversion

    DEFF Research Database (Denmark)

    Caballero Jambrina, Antonio; Zibar, Darko; Tafur Monroy, Idelfonso

    Detection of high speed radio signals is a challenge for next generation radio-over-fiber links, requiring high bandwidth and linearity in the receiver. By using photonic downconversion in a coherent receiver, it is possible to detect signals exceeding the electrical bandwidth of the receiver...

  5. GHz wireless On-off-Keying link employing all photonic RF carrier generation and digital coherent detection

    DEFF Research Database (Denmark)

    Sambaraju, Rakesh; Zibar, Darko; Caballero Jambrina, Antonio

    2010-01-01

    Gb/s wireless signals at 82, 88 and 100 GHz carrier frequencies are successfully generated by heterodyne mixing of two optical carriers. A photonic detection technique with optical coherent receiver and digital signal processing is implemented for signal demodulation....

  6. Digital circuit boards mach 1 GHz

    CERN Document Server

    Morrison, Ralph

    2012-01-01

    A unique, practical approach to the design of high-speed digital circuit boards The demand for ever-faster digital circuit designs is beginning to render the circuit theory used by engineers ineffective. Digital Circuit Boards presents an alternative to the circuit theory approach, emphasizing energy flow rather than just signal interconnection to explain logic circuit behavior. The book shows how treating design in terms of transmission lines will ensure that the logic will function, addressing both storage and movement of electrical energy on these lines. It cove

  7. Basic digital signal processing

    CERN Document Server

    Lockhart, Gordon B

    1985-01-01

    Basic Digital Signal Processing describes the principles of digital signal processing and experiments with BASIC programs involving the fast Fourier theorem (FFT). The book reviews the fundamentals of the BASIC program, continuous and discrete time signals including analog signals, Fourier analysis, discrete Fourier transform, signal energy, power. The text also explains digital signal processing involving digital filters, linear time-variant systems, discrete time unit impulse, discrete-time convolution, and the alternative structure for second order infinite impulse response (IIR) sections.

  8. Digitally programmable signal generator

    International Nuclear Information System (INIS)

    Priatko, G.J.; Kaskey, J.A.

    1988-01-01

    A digitally programmable signal generator (DPSG) includes a first memory from which data is written into a second memory formed of n banks. Each bank includes four memories and a multiplexer, the banks being read once during each time frame, the read-out bits being multiplexed and fed out serially in synchronism with a plurality of clock pulses occuring during a time frame. The resulting serial bit streams may be fed in parallel to a digital-to-analog converter. The DPSG can be used in applications such as Atomic Vapor Laser Isotope Separation (AVLIS) to create an optimal match between the process laser's spectral profile and that of the vaporized material, optical telecommunications, non-optical telecommunication in the microwave and radio spectrum, radar, electronic countermeasures, high speed computer interconnects, local area networks, high definition video transport and the multiplexing of large quantities of slow digital memory into high speed data streams. This invention extends the operation of DPSGs into the GHz range. (author)

  9. A 4 GHz digital receiver using the Uniboard platform

    Science.gov (United States)

    Comoretto, Giovanni; Russo, Antonietta; Quertier, Benjamin; Cais, Philippe; Camino, Pascal

    2012-09-01

    The Uniboard is a general purpose board, developed as a part of the Radionet FP7 program, that hosts 8 Altera StratixIV FPGAs interconnected by high speed links. It can be used standalone or as a part of a more complex system. The Digital receiver application uses a single Uniboard to implement a flexible packetization of a wideband signal in the frequency domain. It accepts a 4 GHz (8 GS/s) input bandwidth and provides up to 64 output bands. The bandwidth and position of each output band can be independently adjusted. The input signal is first analyzed by a polyphase filterbank, that splits the input band into 32 sub-bands with a bandwidth of 190 MHz and a spacing of 128 MHz. The overlap among adjacent bands allows the positioning of the output bands without dead regions. This filterbank is followed by an array of digitally defined downconverters, each one composed of a mixer/LO and a variable decimation filter. The filter band can be adjusted in binary steps from 1 to 128 MHz. Using tap recirculation, the filter shape remains constant over this whole range, with about 60 dB of stopband rejection and 90% usable passband. The output bands are packetized according to the VDIF VLBI standard, over eight 10G Ethernet links. Further processing can be done either on board, or in a cluster of conventional PCs. In addition, high speed ADC are in-house developed (ASIC 65nm CMOS STmicroelectronics) to feed the Uniboard card with 8GS/s, 4GHz BW, 3bits samples.

  10. Up to 40 Gb/s wireless signal generation and demodulation in 75-110 GHz band using photonic techniques

    DEFF Research Database (Denmark)

    Sambaraju, R.; Zibar, Darko; Caballero Jambrina, Antonio

    2010-01-01

    Record wireless signal capacity of up to 40 Gb/s is demonstrated in the 75-110 GHz band. All-optical OFDM and photonic up-conversion are used for generation and digital coherent detection for demodulation....

  11. Digital signal processing

    CERN Document Server

    O'Shea, Peter; Hussain, Zahir M

    2011-01-01

    In three parts, this book contributes to the advancement of engineering education and that serves as a general reference on digital signal processing. Part I presents the basics of analog and digital signals and systems in the time and frequency domain. It covers the core topics: convolution, transforms, filters, and random signal analysis. It also treats important applications including signal detection in noise, radar range estimation for airborne targets, binary communication systems, channel estimation, banking and financial applications, and audio effects production. Part II considers sel

  12. 125-GHz Microwave Signal Generation Employing an Integrated Pulse Shaper

    DEFF Research Database (Denmark)

    Liao, Shasha; Ding, Yunhong; Dong, Jianji

    2017-01-01

    tap. By controlling the thermal heaters on the amplitude modulators, we obtain several signals centered at 125 GHz with typical envelopes, such as square envelope, triangular envelope, sawtooth envelope, Gaussian envelope, etc. Our scheme has some significant advantages, such as the central frequency...

  13. The newest digital signal processing

    International Nuclear Information System (INIS)

    Lee, Chae Uk

    2002-08-01

    This book deal with the newest digital signal processing, which contains introduction on conception of digital signal processing, constitution and purpose, signal and system such as signal, continuos signal, discrete signal and discrete system, I/O expression on impress response, convolution, mutual connection of system and frequency character,z transform of definition, range, application of z transform and relationship with laplace transform, Discrete fourier, Fast fourier transform on IDFT algorithm and FFT application, foundation of digital filter of notion, expression, types, frequency characteristic of digital filter and design order of filter, Design order of filter, Design of FIR digital filter, Design of IIR digital filter, Adaptive signal processing, Audio signal processing, video signal processing and application of digital signal processing.

  14. Design of eight-channel ADC card for GHz signal conversion

    CERN Document Server

    Habib, Samer Bou; Jalmuzna, Wojciech; Jezynski, Tomasz

    2011-01-01

    This paper describes the design of an eight-channel ATCA card suited for direct analog-to-digital conversion of 1.3 GHz signals with a maximum ADC clock frequency of 500 MHz. The undersampling operation is used for signal conversion. This card was designed for the needs of the LLRF system of the FLASH and XFEL accelerators. The designed module consists of a main ATCA board with eight ADCs, FPGA unit, memory, power supply and diagnostic circuits. The main ATCA card allows connecting a daughter board with IPMI, CPU and fast interfaces for communication purposes. This paper describes such issues as system organization allowing acquisition of data at such high data rates, circuit synchronization by high-quality clock signals, CPU and connectivity features, 20-layer PCB design and techniques used for high-frequency signals transmission and matching.

  15. Fast digitizing and digital signal processing of detector signals

    International Nuclear Information System (INIS)

    Hannaske, Roland

    2008-01-01

    A fast-digitizer data acquisition system recently installed at the neutron time-of-flight experiment nELBE, which is located at the superconducting electron accelerator ELBE of Forschungszentrum Dresden-Rossendorf, is tested with two different detector types. Preamplifier signals from a high-purity germanium detector are digitized, stored and finally processed. For a precise determination of the energy of the detected radiation, the moving-window deconvolution algorithm is used to compensate the ballistic deficit and different shaping algorithms are applied. The energy resolution is determined in an experiment with γ-rays from a 22 Na source and is compared to the energy resolution achieved with analogously processed signals. On the other hand, signals from the photomultipliers of barium fluoride and plastic scintillation detectors are digitized. These signals have risetimes of a few nanoseconds only. The moment of interaction of the radiation with the detector is determined by methods of digital signal processing. Therefore, different timing algorithms are implemented and tested with data from an experiment at nELBE. The time resolutions achieved with these algorithms are compared to each other as well as to reference values coming from analog signal processing. In addition to these experiments, some properties of the digitizing hardware are measured and a program for the analysis of stored, digitized data is developed. The analysis of the signals shows that the energy resolution achieved with the 10-bit digitizer system used here is not competitive to a 14-bit peak-sensing ADC, although the ballistic deficit can be fully corrected. However, digital methods give better result in sub-ns timing than analog signal processing. (orig.)

  16. 60 GHz 5-bit digital controlled phase shifter in a digital 40 nm CMOS technology without ultra-thick metals

    NARCIS (Netherlands)

    Gao, H.; Ying, K.; Matters-Kammerer, M.K.; Harpe, P.; Wang, B.; Liu, B.; Serdijn, W.A.; Baltus, P.G.M.

    2016-01-01

    A 5-bit digital controlled switch-type passive phase shifter realised in a 40 nm digital CMOS technology without ultra-thick metals for the 60 GHz Industrial, Scientific and Medical (ISM) band is presented. A patterned shielding with electromagnetic bandgap structure and a stacked metals method to

  17. Digital signal coding

    Energy Technology Data Exchange (ETDEWEB)

    Gaunt, R.

    1997-05-01

    It seems that digital video has gone by as many names as Jim Blinn has Siggraph ribbons. Some of its various formats and names are: DV, Dl, 4:2:2, CCIR 601-1, ITU-Rec. 601-4,, SMPTE RP125M, and SMPTE 259M. CCIR and CCITT were both absorbed into their parent organization, the International Telecommunications Union (ITU), so technically speaking, CCIR 601 has been renamed to ITU-Rec. 601-4 (``Rec.`` stands for recommendation). But convention is often hard to change, so for some time you will see and hear Dl and CCIR 601 used for serial digital component video. Below are brief descriptions of the various names and formats for digital video.

  18. Digital Signal Processors

    Indian Academy of Sciences (India)

    A computer controlling the motion of a satellite should acquire signals from the satellite while it is in motion, compute corrections (if required) to the trajectory and send control signals back within a specified time for effective control. Delays may be fatal to ..... emulators and system evaluation tools have facilitated concurrent.

  19. Digital predistortion of 75–110 GHz W-band frequency multiplier for fiber wireless short range access systems

    DEFF Research Database (Denmark)

    Zhao, Ying; Deng, Lei; Pang, Xiaodan

    2011-01-01

    We present a W-band fiber-wireless transmission system based on a nonlinear frequency multiplier for high-speed wireless short range access applications. By implementing a baseband digital signal predistortion scheme, intensive nonlinear distortions induced in a sextuple frequency multiplier can...... be effectively pre-compensated. Without using costly W-band components, a transmission system with 26km fiber and 4m wireless transmission operating at 99.6GHz is experimentally validated. Adjacent-channel power ratio (ACPR) improvements for IQ-modulated vector signals are guaranteed and transmission...

  20. Digital coherent receiver for subcarrier multiplexed phase modulated radio-over-fibre signals

    DEFF Research Database (Denmark)

    Zibar, Darko; Larsen, Knud J.; Tafur Monroy, Idelfonso

    2009-01-01

    Digital coherent detection of multi-channel subcarrier multiplexed optically phase-modulated radio-over-fibre signals is experimentally demonstrated. Successful detection after transmission over a 40 km long fibre link of four or five 25 Mbaud BPSK/QPSK subcarrier channels in 5 GHz bandwidth...... is demonstrated using offline digital signal processing....

  1. Fiber Wireless Transmission of 8.3 Gb/s/ch QPSK-OFDM Signals in 75-110 GHz Band

    DEFF Research Database (Denmark)

    Deng, Lei; Beltrán Ramírez, Marta; Pang, Xiaodan

    2012-01-01

    In this paper, we present a scalable high speed Wband (75-110 GHz) fiber wireless communication system. By using an optical frequency comb generator, 3-channel 8.3 Gb/s/ch optical orthogonal frequency division multiplexing (OOFDM) baseband signals in a 15 GHz bandwidth are seamlessly translated...... from the optical to the wireless domain. The W-band wireless carrier is generated from heterodyne mixing the OOFDM baseband signal with a free-running laser. A W-band electronic down-converter and a digital signal processing (DSP) based receiver is used. 3-channel QPSK-OFDM W-band wireless signals...

  2. PSpice for digital signal processing

    CERN Document Server

    Tobin, Paul

    2007-01-01

    PSpice for Digital Signal Processing is the last in a series of five books using Cadence Orcad PSpice version 10.5 and introduces a very novel approach to learning digital signal processing (DSP). DSP is traditionally taught using Matlab/Simulink software but has some inherent weaknesses for students particularly at the introductory level. The 'plug in variables and play' nature of these software packages can lure the student into thinking they possess an understanding they don't actually have because these systems produce results quicklywithout revealing what is going on. However, it must be

  3. Chaotic signals in digital communications

    CERN Document Server

    Eisencraft, Marcio; Suyama, Ricardo

    2013-01-01

    Chaotic Signals in Digital Communications combines fundamental background knowledge with state-of-the-art methods for using chaotic signals and systems in digital communications. The book builds a bridge between theoretical works and practical implementation to help researchers attain consistent performance in realistic environments. It shows the possible shortcomings of the chaos-based communication systems proposed in the literature, particularly when they are subjected to non-ideal conditions. It also presents a toolbox of techniques for researchers working to actually implement such system

  4. A fully integrated sensor SoC with digital calibration hardware and wireless transceiver at 2.4 GHz.

    Science.gov (United States)

    Kim, Dong-Sun; Jang, Sung-Joon; Hwang, Tae-Ho

    2013-05-21

    A single-chip sensor system-on-a-chip (SoC) that implements radio for 2.4 GHz, complete digital baseband physical layer (PHY), 10-bit sigma-delta analog-to-digital converter and dedicated sensor calibration hardware for industrial sensing systems has been proposed and integrated in a 0.18-μm CMOS technology. The transceiver's building block includes a low-noise amplifier, mixer, channel filter, receiver signal-strength indicator, frequency synthesizer, voltage-controlled oscillator, and power amplifier. In addition, the digital building block consists of offset quadrature phase-shift keying (OQPSK) modulation, demodulation, carrier frequency offset compensation, auto-gain control, digital MAC function, sensor calibration hardware and embedded 8-bit microcontroller. The digital MAC function supports cyclic redundancy check (CRC), inter-symbol timing check, MAC frame control, and automatic retransmission. The embedded sensor signal processing block consists of calibration coefficient calculator, sensing data calibration mapper and sigma-delta analog-to-digital converter with digital decimation filter. The sensitivity of the overall receiver and the error vector magnitude (EVM) of the overall transmitter are -99 dBm and 18.14%, respectively. The proposed calibration scheme has a reduction of errors by about 45.4% compared with the improved progressive polynomial calibration (PPC) method and the maximum current consumption of the SoC is 16 mA.

  5. A Fully Integrated Sensor SoC with Digital Calibration Hardware and Wireless Transceiver at 2.4 GHz

    Directory of Open Access Journals (Sweden)

    Dong-Sun Kim

    2013-05-01

    Full Text Available A single-chip sensor system-on-a-chip (SoC that implements radio for 2.4 GHz, complete digital baseband physical layer (PHY, 10-bit sigma-delta analog-to-digital converter and dedicated sensor calibration hardware for industrial sensing systems has been proposed and integrated in a 0.18-μm CMOS technology. The transceiver’s building block includes a low-noise amplifier, mixer, channel filter, receiver signal-strength indicator, frequency synthesizer, voltage-controlled oscillator, and power amplifier. In addition, the digital building block consists of offset quadrature phase-shift keying (OQPSK modulation, demodulation, carrier frequency offset compensation, auto-gain control, digital MAC function, sensor calibration hardware and embedded 8-bit microcontroller. The digital MAC function supports cyclic redundancy check (CRC, inter-symbol timing check, MAC frame control, and automatic retransmission. The embedded sensor signal processing block consists of calibration coefficient calculator, sensing data calibration mapper and sigma-delta analog-to-digital converter with digital decimation filter. The sensitivity of the overall receiver and the error vector magnitude (EVM of the overall transmitter are −99 dBm and 18.14%, respectively. The proposed calibration scheme has a reduction of errors by about 45.4% compared with the improved progressive polynomial calibration (PPC method and the maximum current consumption of the SoC is 16 mA.

  6. Digital storage of repeated signals

    International Nuclear Information System (INIS)

    Prozorov, S.P.

    1984-01-01

    An independent digital storage system designed for repeated signal discrimination from background noises is described. The signal averaging is performed off-line in the real time mode by means of multiple selection of the investigated signal and integration in each point. Digital values are added in a simple summator and the result is recorded the storage device with the volume of 1024X20 bit from where it can be output on an oscillograph, a plotter or transmitted to a compUter for subsequent processing. The described storage is reliable and simple device on one base of which the systems for the nuclear magnetic resonapce signal acquisition in different experiments are developed

  7. A 1 GHz sample rate, 256-channel, 1-bit quantization, CMOS, digital correlator chip

    Science.gov (United States)

    Timoc, C.; Tran, T.; Wongso, J.

    1992-01-01

    This paper describes the development of a digital correlator chip with the following features: 1 Giga-sample/second; 256 channels; 1-bit quantization; 32-bit counters providing up to 4 seconds integration time at 1 GHz; and very low power dissipation per channel. The improvements in the performance-to-cost ratio of the digital correlator chip are achieved with a combination of systolic architecture, novel pipelined differential logic circuits, and standard 1.0 micron CMOS process.

  8. A 3-5GHz UWB CMOS Receiver with Digital Control Technique

    DEFF Research Database (Denmark)

    Han, Bo; Liu, Mengmeng; Ge, Ning

    2010-01-01

    This article presents a CMOS receiver that works for 3-5GHz low band SC-UWB. The receiver contains PLL, Mixer, and VGA. Double down conversion is adopted in the receiver to overcome the orthogonal clock design difficulty; digital assisted RF control method is used to increase the stability...

  9. Digital seismic station. Digital signal processing

    Science.gov (United States)

    Pazos Garcia, Antonio A.

    This work have two clearly differentiated parts. The first one refers to the instrumental development of a digital short period seismic station, while in second one some aspects of the digital signal processing are studied. In the first part, it is shown as a simple capacitor in series with the load resistance increase the band width of the response in more than 30%, without any reduction of the effective gain and the internal noise is not increased regarding the classical load. Also, the system of acquisition has been developed, based on the analogical-digital converter CS5323/CS5322 that it provides a dynamic range of 130 decibels to 125 mps. The data acquisition for the parallel port of an embedded PC, working with LINUX operating system, is an innovation in this instrumental field. The programs and the necessary drivers were developed. The synchronization system was developed by a PLL software that permit a precision better than one millisecond. Finally, the calibration methods proposed by means of the measure of the equivalent impedance of the sensor (parametric method), as well as the modifications of the empiric calibration method by comparison the response of two sensors have been decisive, suggesting that the usually accepted models suffer of some parasite capacities that would justify the observed differences between both methods. In second part, a detailed analysis on the design of digital filters is showed, as much FIR as IIR filters. A non-linear filter that applies the coherent structures for levels, based on the Wavelet transform, is proposed. It includes the detection and reduction of "spikes" and a method for filtering periodic noises, based on the time Fourier series. Finally, an exhaustive comparison of several detection algorithms, working on a single component, is made, analyzing the detection percentages and their "picking" capabilities. Their results show that none of them is able to adapt to all the circumstances, highlighting those based on

  10. BPSK Demodulation Using Digital Signal Processing

    Science.gov (United States)

    Garcia, Thomas R.

    1996-01-01

    A digital communications signal is a sinusoidal waveform that is modified by a binary (digital) information signal. The sinusoidal waveform is called the carrier. The carrier may be modified in amplitude, frequency, phase, or a combination of these. In this project a binary phase shift keyed (BPSK) signal is the communication signal. In a BPSK signal the phase of the carrier is set to one of two states, 180 degrees apart, by a binary (i.e., 1 or 0) information signal. A digital signal is a sampled version of a "real world" time continuous signal. The digital signal is generated by sampling the continuous signal at discrete points in time. The rate at which the signal is sampled is called the sampling rate (f(s)). The device that performs this operation is called an analog-to-digital (A/D) converter or a digitizer. The digital signal is composed of the sequence of individual values of the sampled BPSK signal. Digital signal processing (DSP) is the modification of the digital signal by mathematical operations. A device that performs this processing is called a digital signal processor. After processing, the digital signal may then be converted back to an analog signal using a digital-to-analog (D/A) converter. The goal of this project is to develop a system that will recover the digital information from a BPSK signal using DSP techniques. The project is broken down into the following steps: (1) Development of the algorithms required to demodulate the BPSK signal; (2) Simulation of the system; and (3) Implementation a BPSK receiver using digital signal processing hardware.

  11. Digital Signal Processor For GPS Receivers

    Science.gov (United States)

    Thomas, J. B.; Meehan, T. K.; Srinivasan, J. M.

    1989-01-01

    Three innovative components combined to produce all-digital signal processor with superior characteristics: outstanding accuracy, high-dynamics tracking, versatile integration times, lower loss-of-lock signal strengths, and infrequent cycle slips. Three components are digital chip advancer, digital carrier downconverter and code correlator, and digital tracking processor. All-digital signal processor intended for use in receivers of Global Positioning System (GPS) for geodesy, geodynamics, high-dynamics tracking, and ionospheric calibration.

  12. Digital signal processing for NDT

    International Nuclear Information System (INIS)

    Georgel, B.

    1994-01-01

    NDT begins to adapt and use the most recent developments of digital signal and image processing. We briefly sum up the main characteristics of NDT situations (particularly noise and inverse problem formulation) and comment on techniques already used or just emerging (SAFT, split spectrum, adaptive learning network, noise reference filtering, stochastic models, neural networks). This survey is focused on ultrasonics, eddy currents and X-ray radiography. The final objective of end users (availability of automatic diagnosis systems) cannot be achieved only by signal processing algorithms. A close cooperation with other techniques such as artificial intelligence has therefore to be implemented. (author). 20 refs

  13. Digital Signal Processing applied to Physical Signals

    CERN Document Server

    Alberto, Diego; Musa, L

    2011-01-01

    It is well known that many of the scientific and technological discoveries of the XXI century will depend on the capability of processing and understanding a huge quantity of data. With the advent of the digital era, a fully digital and automated treatment can be designed and performed. From data mining to data compression, from signal elaboration to noise reduction, a processing is essential to manage and enhance features of interest after every data acquisition (DAQ) session. In the near future, science will go towards interdisciplinary research. In this work there will be given an example of the application of signal processing to different fields of Physics from nuclear particle detectors to biomedical examinations. In Chapter 1 a brief description of the collaborations that allowed this thesis is given, together with a list of the publications co-produced by the author in these three years. The most important notations, definitions and acronyms used in the work are also provided. In Chapter 2, the last r...

  14. Interfering signals and digital measurements

    International Nuclear Information System (INIS)

    Stulik, P.; Pilat, M.

    1976-01-01

    The possible occurrence was studied of unweighted voltage interference in measuring channels and the effect of the voltage on the measuring system where digital technology is used in the WWR-S reactor experimental loops. Various types of voltmeters were evaluated in the gas loop during measurements of the output signals of a Ni-NiCr jacket thermocouple, this both with an insulated and a noninsulated end. Also studied was digital measurement in measuring channels with vanadium SPN detectors. Two identical detectors were installed in the middle of the core and, assuming an identical neutron flux for both detectors, the effects were investigated of a different cable route design, of the combination of the connection of measuring central input circuits on the size of fluctuations of the measured output signal of both detectors, etc. The optimal value was also studied of the loading resistor incorporated in the measuring circuit. The relation was derived for digital measurement accuracy. It was confirmed experimentally and by calculation that unweighted voltage in series has the greatest effect on measurement accuracy. (Z.M.)

  15. A 7-8 GHz serrodyne modulator in SiGe for MIMO signal generation

    NARCIS (Netherlands)

    Withagen, J.C.J.G.; Annema, Anne J.; Nauta, Bram; van Vliet, Frank Edward

    2014-01-01

    An 8-bit 360o sawtooth modulated phase shifter is used to apply very small frequency offsets to RF signals between 7 and 8 GHz. Offsets between 6 Hz and 10MHz can be obtained. Such frequency offsets can be used to generate orthogonal signals, which are required in e.g. MIMO applications. Each

  16. Digital signal processing an experimental approach

    CERN Document Server

    Engelberg, Shlomo

    2008-01-01

    Digital Signal Processing is a mathematically rigorous but accessible treatment of digital signal processing that intertwines basic theoretical techniques with hands-on laboratory instruction. Divided into three parts, the book covers various aspects of the digital signal processing (DSP) ""problem."" It begins with the analysis of discrete-time signals and explains sampling and the use of the discrete and fast Fourier transforms. The second part of the book???covering digital to analog and analog to digital conversion???provides a practical interlude in the mathematical content before Part II

  17. Digital signal processing using MATLAB

    CERN Document Server

    Schilling, Robert L

    2016-01-01

    Focus on the development, implementation, and application of modern DSP techniques with DIGITAL SIGNAL PROCESSING USING MATLAB(R), 3E. Written in an engaging, informal style, this edition immediately captures your attention and encourages you to explore each critical topic. Every chapter starts with a motivational section that highlights practical examples and challenges that you can solve using techniques covered in the chapter. Each chapter concludes with a detailed case study example, a chapter summary with learning outcomes, and practical homework problems cross-referenced to specific chapter sections for your convenience. DSP Companion software accompanies each book to enable further investigation. The DSP Companion software operates with MATLAB(R) and provides intriguing demonstrations as well as interactive explorations of analysis and design concepts.

  18. A high-speed superconducting digital autocorrelator operating at 20.48 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, Steven B [HYPRES, Incorporated, 175 Clearbrook Road, Elmsford, NY 10523 (United States); Engseth, Henrik [Department of Microelectronics and Nanoscience, Chalmers University, Goeteborg SE-412 96 (Sweden)

    2007-11-15

    Digital autocorrelators have a number of applications, such as in astronomical observation in the terahertz range, and for spectrum monitoring over wide radio-frequency bands. We have simulated, designed and tested 16-lag superconducting digital autocorrelator circuits with parallel and also with serial data outputs. By using a novel clock line and a target critical current density of 4.5 kA cm{sup -2}, we have successfully tested this digital circuit up to a clock rate of 20.48 GHz with negligible bit error rates on each lag. Moreover, this autocorrelator design can be expanded with a larger number of lags by tiling chips in a multi-chip module. We also include details of our first multi-chip design.

  19. NASA 60 GHz intersatellite communication link definition study. Addendum A: Mixed baseband and IF signals

    Science.gov (United States)

    1986-01-01

    As part of a definition study for a 60 GHz intersatellite communications link system (ICLS), baseline design concepts for a channelized crosslink were identified. The crosslink would allow communications between geostationary satellites of the planned Tracking and Data Acquisition System (TDAS) and would accommodate a mixture of frequency translation coherent links (bent pipe links) and baseband-in/baseband-out links (mod/demod links). A 60 GHz communication system was developed for sizing and analyzing the crosslink. For the coherent links this system translates incoming signals directly up to the 60 GHz band; trunks the signals across from one satellite to a second satellite at 60 GHz then down converts to the proper frequency for re-transmission from the second satellite without converting to any intermediate frequencies. For the baseband-in/baseband-out links the baseband data is modulated on to the 60 GHz carrier at the transmitting satellite and demodulated at the receiving satellite. The frequency plan, equipment diagrams, and link calculations are presented along with results from sizing and reliability analyses.

  20. Digital signal processing for fiber nonlinearities [Invited

    DEFF Research Database (Denmark)

    Cartledge, John C.; Guiomar, Fernando P.; Kschischang, Frank R.

    2017-01-01

    This paper reviews digital signal processing techniques that compensate, mitigate, and exploit fiber nonlinearities in coherent optical fiber transmission systems......This paper reviews digital signal processing techniques that compensate, mitigate, and exploit fiber nonlinearities in coherent optical fiber transmission systems...

  1. High-Capacity 60 GHz and 75–110 GHz Band Links Employing All-Optical OFDM Generation and Digital Coherent Detection

    DEFF Research Database (Denmark)

    Caballero Jambrina, Antonio; Zibar, Darko; Sambaraju, Rakesh

    2012-01-01

    The performance of wireless signal generation and detection at millimeter-wave frequencies using baseband optical means is analyzed and experimentally demonstrated. Multigigabit wireless signal generation is achieved based on all-optical orthogonal frequency division multiplexing (OFDM) and photo......The performance of wireless signal generation and detection at millimeter-wave frequencies using baseband optical means is analyzed and experimentally demonstrated. Multigigabit wireless signal generation is achieved based on all-optical orthogonal frequency division multiplexing (OFDM...... scalability and bit-rate transparency of our proposed approach, we experimentally demonstrated generation and detection in the 60 GHz and 75–110 GHz band of an all-optical OFDM quadrature phase shift keying, with two and three subcarriers, for a total bit rate over 20 Gb/ s....

  2. Advanced digital signal processing and noise reduction

    CERN Document Server

    Vaseghi, Saeed V

    2008-01-01

    Digital signal processing plays a central role in the development of modern communication and information processing systems. The theory and application of signal processing is concerned with the identification, modelling and utilisation of patterns and structures in a signal process. The observation signals are often distorted, incomplete and noisy and therefore noise reduction, the removal of channel distortion, and replacement of lost samples are important parts of a signal processing system. The fourth edition of Advanced Digital Signal Processing and Noise Reduction updates an

  3. Digital Signal Processing Based Biotelemetry Receivers

    Science.gov (United States)

    Singh, Avtar; Hines, John; Somps, Chris

    1997-01-01

    This is an attempt to develop a biotelemetry receiver using digital signal processing technology and techniques. The receiver developed in this work is based on recovering signals that have been encoded using either Pulse Position Modulation (PPM) or Pulse Code Modulation (PCM) technique. A prototype has been developed using state-of-the-art digital signal processing technology. A Printed Circuit Board (PCB) is being developed based on the technique and technology described here. This board is intended to be used in the UCSF Fetal Monitoring system developed at NASA. The board is capable of handling a variety of PPM and PCM signals encoding signals such as ECG, temperature, and pressure. A signal processing program has also been developed to analyze the received ECG signal to determine heart rate. This system provides a base for using digital signal processing in biotelemetry receivers and other similar applications.

  4. Wideband Spectroscopy: The Design and Implementation of a 3 GHz Bandwidth, 8192 Channel, Polyphase Digital Spectrometer

    Science.gov (United States)

    Monroe, Ryan M.

    2011-01-01

    A family of state-of-the-art digital Fourier transform spectrometers has been developed, with a combination of high bandwidth and fine resolution unavailable elsewhere. Analog signals consisting of radiation emitted by constituents in planetary atmospheres or galactic sources are downconverted and subsequently digitized by a pair of interleaved Analog-to-Digital Converters, (ADC). This 6 Gsps (giga-sample per second) digital representation of the analog signal is then processed through an FPGA-based streaming Fast Fourier Transform (FFT), the key development described below. Digital spectrometers have many advantages over previously used analog spectrometers, especially in terms of accuracy and resolution, both of which are particularly important for the type of scientific questions to be addressed with next-generation radiometers. the implementation, results and underlying math for this spectrometer, as well as, potential for future extension to even higher bandwidth, resolution and channel orthogonality, needed to support proposed future advanced atmospheric science and radioastronomy, are discussed.

  5. Wideband Spectroscopy: The Design and Implementation of a 3 GHz, 2048 Channel Digital Spectrometer

    Science.gov (United States)

    Monroe, Ryan M.

    2011-01-01

    A state-of-the-art digital Fourier Transform spectrometer has been developed, with a combination of high bandwidth and fine resolution unavailable elsewhere. Analog signals consisting of radiation emitted by constituents in planetary atmospheres or galactic sources are downconverted and subsequently digitized by a pair of interleaved Analog-to-Digital Converters (ADC). This 6 Gsps (giga sample per second) digital representation of the analog signal is then processed through an FPGA-based streaming Fast Fourier Transform (FFT), the key development described below. Digital spectrometers have many advantages over previously used analog spectrometers, especially in terms of accuracy and resolution, both of which are particularly important for the type of scientific questions to be addressed with next-generation radiometers. The implementation, results and underlying math for this spectrometer, as well as potential for future extension to even higher bandwidth, resolution and channel orthogonality, needed to support proposed future advanced atmospheric science and radioastronomy, are discussed.

  6. Digital signal processing - growth of a technology

    International Nuclear Information System (INIS)

    Peek, J.B.H.

    1985-01-01

    The rapid development of microelectronics has led to an increasing extent in circuits and systems for digital signal processing. This happened first in professional applications, e.g. geophysics, astronomy and space flight, and now, with the Compact Disc player, these techniques have entered the consumer field. In the near future digital TV applications will undoubtedly follow. This article outlines a number of the developments behind the advancing 'digitization' of modern technology. The article also considers the main advantages and disadvantages of digital signal processing the main modules now used and some common applications. Particular attention is paid to medical applications. (Auth.)

  7. Digital Predistortion of 75-110GHzW-Band Frequency Multiplier for Fiber Wireless Short Range Access Systems

    DEFF Research Database (Denmark)

    Zhao, Ying; Pang, Xiaodan; Deng, Lei

    2011-01-01

    We present a digital predistortion technique to effectively compensate high nonlinearity of a sextuple multiplier operating at 99.6GHz. An 18.9dB adjacent-channel power ratio (ACPR) improvement is guaranteed and a W-band fiber-wireless system is experimentally investigated.......We present a digital predistortion technique to effectively compensate high nonlinearity of a sextuple multiplier operating at 99.6GHz. An 18.9dB adjacent-channel power ratio (ACPR) improvement is guaranteed and a W-band fiber-wireless system is experimentally investigated....

  8. Digital signal processing with kernel methods

    CERN Document Server

    Rojo-Alvarez, José Luis; Muñoz-Marí, Jordi; Camps-Valls, Gustavo

    2018-01-01

    A realistic and comprehensive review of joint approaches to machine learning and signal processing algorithms, with application to communications, multimedia, and biomedical engineering systems Digital Signal Processing with Kernel Methods reviews the milestones in the mixing of classical digital signal processing models and advanced kernel machines statistical learning tools. It explains the fundamental concepts from both fields of machine learning and signal processing so that readers can quickly get up to speed in order to begin developing the concepts and application software in their own research. Digital Signal Processing with Kernel Methods provides a comprehensive overview of kernel methods in signal processing, without restriction to any application field. It also offers example applications and detailed benchmarking experiments with real and synthetic datasets throughout. Readers can find further worked examples with Matlab source code on a website developed by the authors. * Presents the necess...

  9. 400-GHz wireless transmission of 60-Gb/s nyquist-QPSK signals using UTC-PD and heterodyne mixer

    DEFF Research Database (Denmark)

    Yu, Xianbin; Asif, Rameez; Piels, Molly

    2016-01-01

    We experimentally demonstrate an optical network compatible high-speed optoelectronics THz wireless transmission system operating at 400-GHz band. In the experiment, optical Nyquist quadrature phase-shift keying signals in a 12.5-GHz ultradense wavelength-division multiplexing grid is converted...

  10. Twelve-bit 20-GHz reduced size pipeline accumulator in 0.25 μm SiGe:C technology for direct digital synthesiser applications

    DEFF Research Database (Denmark)

    Jensen, Brian Sveistrup; Khafaji, M. M.; Johansen, T. K.

    2012-01-01

    /Fmax of 180/220 GHz. The accumulator architecture omits the pre-skewing registers of the pipeline, thereby lowering both power consumption and circuit complexity. Some limitations to this design are discussed and the necessary equations for determining the phase jump encountered each time the control word...... (synthesised frequency) is changed are presented. For many applications employing signal processing after detection, this phase shift can then be corrected for. Compared to a full pipeline architecture (omitting the input circuitry for the most significant bit, as is customary for such designs......This article presents a 20 GHz, 12-bit pipeline accumulator with a reduced number of registers, suitable for direct digital synthesiser (DDS) applications. The accumulator is implemented in the IHP SG25H1 (0.25 μm) SiGe:C technology featuring heterojunction bipolar transistors (HBTs) with Ft...

  11. Twelve-bit 20-GHz reduced size pipeline accumulator in 0.25 µm SiGe:C technology for direct digital synthesiser applications

    DEFF Research Database (Denmark)

    Jensen, Brian Sveistrup; Khafaji, M. Mahdi; Johansen, Tom Keinicke

    2012-01-01

    /Fmax of 180/220 GHz respectively. The accumulator architecture omits the pre-skewing registers of the pipeline, thereby lowering both power consumption and circuit complexity. Some limitations to this design are discussed and the necessary equations for determining the phase jump encountered each time......This article presents a 20 GHz, 12-bit pipeline accumulator with a reduced number of registers, suitable for direct digital synthesizer (DDS) applications. The accumulator is implemented in the IHP SG25H1 (0.25um) SiGe:C technology featuring heterojunction bipolar transistors (HBT) with Ft...... the control word (synthesized frequency) is changed are presented. For many applications employing signal processing after detection, this phase shift can then be corrected for. Compared to a full pipeline architecture, the implemented 12-bit accumulator reduces the number of registers by 55% and the power...

  12. Digital control card based on digital signal processor

    International Nuclear Information System (INIS)

    Hou Shigang; Yin Zhiguo; Xia Le

    2008-01-01

    A digital control card based on digital signal processor was developed. Two Freescale DSP-56303 processors were utilized to achieve 3 channels proportional- integral-differential regulations. The card offers high flexibility for 100 MeV cyclotron RF system development. It was used as feedback controller in low level radio frequency control prototype, with the feedback gain parameters continuously adjustable. By using high precision analog to digital converter with 500 kHz sampling rate, a regulation bandwidth of 20 kHz was achieved. (authors)

  13. 23-Gigahertz (GHz) Digital Low Density Radio Communications Link (LDRCL) Operational Test and Evaluation (OT&E) Integration and OT&E Operational Final Test Report

    Science.gov (United States)

    1994-08-01

    Richardson, Texas. MicroNet 23 Digital Radio Microwave Networks, Inc. Digital Channel Bank Wescom Battery/Charger Power Conversion Products (PCP) Remote...TEST CONFIGURATION 3 TABLE 1. 23-GHz DIGITAL SYSTEM EQUIPMENT Equipment Terminal 1 r Terminal 2 Micronet 23 Digital Radio Qty 1 Qty 1 DS1 Croisconnect

  14. An introduction to digital signal processing

    CERN Document Server

    Karl, John H

    1989-01-01

    An Introduction to Digital Signal Processing is written for those who need to understand and use digital signal processing and yet do not wish to wade through a multi-semester course sequence. Using only calculus-level mathematics, this book progresses rapidly through the fundamentals to advanced topics such as iterative least squares design of IIR filters, inverse filters, power spectral estimation, and multidimensional applications--all in one concise volume.This book emphasizes both the fundamental principles and their modern computer implementation. It presents and demonstrates how si

  15. Low power digital signal processing

    DEFF Research Database (Denmark)

    Paker, Ozgun

    2003-01-01

    This thesis introduces a novel approach to programmable and low power platform design for audio signal processing, in particular hearing aids. The proposed programmable platform is a heterogeneous multiprocessor architecture consisting of small and simple instruction set processors called mini......-cores as well as standard DSP/CPU-cores that communicate using message passing. The work has been based on a study of the algorithm suite covering the application domain. The observation of dominant tasks for certain algorithms (FIR, IIR, correlation, etc.) that require custom computational units and special...... data addressing capabilities lead to the design of low power mini-cores. The algorithm suite also consisted of less demanding and/or irregular algorithms (LMS, compression) that required subsample rate signal processing justifying the use of a DSP/CPU-core. The thesis also contributes to the recent...

  16. Efficient AlGaN/GaN Linear and Digital-Switch-Mode Power Amplifiers for Operation at 2GHz

    Science.gov (United States)

    Maroldt, Stephan; Wiegner, Dirk; Vitanov, Stanislav; Palankovski, Vassil; Quay, Rüdiger; Ambacher, Oliver

    This work addresses the enormous efficiency and linearity potential of optimized AlGaN/GaN high-electron mobility transistors (HEMT) in conventional Doherty linear base-station amplifiers at 2.7GHz. Supported by physical device simulation, the work further elaborates on the use of AlGaN/GaN HEMTs in high-speed current-switch-mode class-D (CMCD)/class-S MMICs for data rates of up to 8Gbit/s equivalent to 2GHz RF-operation. The device needs for switch-mode operation are derived and verified by MMIC results in class-S and class-D operation. To the authors' knowledge, this is the first time 2GHz-equivalent digital-switch-mode RF-operation is demonstrated with GaN HEMTs with high efficiency.

  17. A Virtual Laboratory for Digital Signal Processing

    Science.gov (United States)

    Dow, Chyi-Ren; Li, Yi-Hsung; Bai, Jin-Yu

    2006-01-01

    This work designs and implements a virtual digital signal processing laboratory, VDSPL. VDSPL consists of four parts: mobile agent execution environments, mobile agents, DSP development software, and DSP experimental platforms. The network capability of VDSPL is created by using mobile agent and wrapper techniques without modifying the source code…

  18. A 15 GSa/s, 1.5 GHz bandwidth waveform digitizing ASIC

    Science.gov (United States)

    Oberla, Eric; Genat, Jean-Francois; Grabas, Hervé; Frisch, Henry; Nishimura, Kurtis; Varner, Gary

    2014-01-01

    The PSEC4 custom integrated circuit was designed for the recording of fast waveforms for use in large-area time-of-flight detector systems. The ASIC has been fabricated using the IBM-8RF 0.13 μm CMOS process. On each of the six analog channels, PSEC4 employs a switched capacitor array (SCA) of 256 samples deep, a ramp-compare ADC with 10.5 bits of DC dynamic range, and a serial data readout with the capability of region-of-interest windowing to reduce dead time. The sampling rate can be adjusted between 4 and 15 Gigasamples/second (GSa/s) on all channels and is servo-controlled on-chip with a low-jitter delay-locked loop (DLL). The input signals are passively coupled on-chip with a -3 dB analog bandwidth of 1.5 GHz. The power consumption in quiescent sampling mode is less than 50 mW/chip; at a sustained trigger and a readout rate of 50 kHz the chip draws 100 mW. After fixed-pattern pedestal subtraction, the uncorrected integral non-linearity is 0.15% over a 750 mV dynamic range. With a linearity correction, a full 1 V signal voltage range is available. The sampling timebase has a fixed-pattern non-linearity with an RMS of 13%, which can be corrected for precision waveform feature extraction and timing.

  19. Experimental Analysis of 60-GHz VCSEL and ECL Photonic Generation and Transmission of Impulse-Radio Ultra-Wideband Signals

    DEFF Research Database (Denmark)

    Beltran, Marta; Jensen, Jesper Bevensee; Llorente, Roberto

    2011-01-01

    Optical generation of impulse-radio ultra-wideband (UWB) signals in the 60-GHz band is proposed and experimentally demonstrated. External-cavity laser (ECL) and vertical-cavity surface-emitting laser (VCSEL) is employed for frequency up-conversion by heterodyne mixing with a UWB optical signal...

  20. Digital signal processing theory and practice

    CERN Document Server

    Rao, K Deergha

    2018-01-01

    The book provides a comprehensive exposition of all major topics in digital signal processing (DSP). With numerous illustrative examples for easy understanding of the topics, it also includes MATLAB-based examples with codes in order to encourage the readers to become more confident of the fundamentals and to gain insights into DSP. Further, it presents real-world signal processing design problems using MATLAB and programmable DSP processors. In addition to problems that require analytical solutions, it discusses problems that require solutions using MATLAB at the end of each chapter. Divided into 13 chapters, it addresses many emerging topics, which are not typically found in advanced texts on DSP. It includes a chapter on adaptive digital filters used in the signal processing problems for faster acceptable results in the presence of changing environments and changing system requirements. Moreover, it offers an overview of wavelets, enabling readers to easily understand the basics and applications of this po...

  1. Digital signal processing at GEND's data center

    International Nuclear Information System (INIS)

    Jackson, J.E.

    1977-01-01

    The conversion and recording of analog signals in digital form has been an active element in the manufacturing operations of the General Electric Neutron Devices Department (GEND) since 1966. The first computerized data system for these digitized waveforms was implemented at GEND's data center approximately two years later during 1968. The evolution and integration of these two activities at GEND are addressed in this paper. Beginning with the tester--data center interface, emphasis is placed on previous approaches, current capabilities, near-term trends, and future requirements. The digitizing process has developed into a firmly established set of hardware and associated software techniques which has proven itself as an accurate, reliable procedure for capturing waveform characteristics. The most important aspect of this process is the recent trend toward increased sampling rates and a greater number of digitized parameters per operation. The combined effect is a tremendous increase in output data volumes. Since digital signal processing carries the potential for significant contributions to manufacturing quality and reliability, as well as engineering design and development, increased activity in this area appears extremely desirable. 11 figures

  2. Digital signal processing based multi channel analyzer

    International Nuclear Information System (INIS)

    Saklani, Vipin; Meenakshi Sundari, A.; Rai, A.K.; Sarma, C.V.R.

    2013-01-01

    Gamma Ray Spectrometry is an essential tool for mapping radio elemental concentrations and has found widespread applications in mineral exploration, geological mapping and environmental mapping. Spectrometry based on analog amplifiers with Gaussian pulse shaping has been used for more than 40 years. Digital electronics and digital signal processing methods have enhanced the spectrometer specifications. This paper presents the design and development of a FPGA based Gamma Ray Spectrometer featuring 1024 channel Multi Channel Analyser (MCA) with NaI(Tl) scintillation detector. The system shows significant improvements in energy resolution, count rate capability and dead time as compared to its analog counterpart. (author)

  3. Towards 400GBASE 4-lane Solution Using Direct Detection of MultiCAP Signal in 14 GHz Bandwidth per Lane

    DEFF Research Database (Denmark)

    Iglesias Olmedo, Miguel; Tianjian, Zuo; Jensen, Jesper Bevensee

    2013-01-01

    We report on an experimental demonstration of 102 Gbit/s transmission over a 15km single wavelength and polarization fiber link with 14GHz 3dB bandwidth. Novel multiband CAP signaling allows for a 4-lane 400GBASE long reach solution.......We report on an experimental demonstration of 102 Gbit/s transmission over a 15km single wavelength and polarization fiber link with 14GHz 3dB bandwidth. Novel multiband CAP signaling allows for a 4-lane 400GBASE long reach solution....

  4. Concurrent signal combining and channel estimation in digital communications

    Science.gov (United States)

    Ormesher, Richard C [Albuquerque, NM; Mason, John J [Albuquerque, NM

    2011-08-30

    In the reception of digital information transmitted on a communication channel, a characteristic exhibited by the communication channel during transmission of the digital information is estimated based on a communication signal that represents the digital information and has been received via the communication channel. Concurrently with the estimating, the communication signal is used to decide what digital information was transmitted.

  5. Digital data reduction of oscillatory signals

    Science.gov (United States)

    Bebelaar, F.; Schoyer, H. F. R.

    1981-11-01

    A newly developed procedure for determining in an efficient, digital manner the amplitudes and frequencies of the oscillatory components of arbitrary signals is presented. The method is found to be especially useful in those cases where varying amplitudes and frequencies are encountered. The possibility of assigning a noise level criterion, such as minimum double amplitude (MDA) or minimum relative amplitude (MRA), enlarges the versatility of this procedure in comparison with other methods. Even for large amounts of data, computer times remain limited.

  6. Direct video acquisition by digital signal processors

    Science.gov (United States)

    de Sa, Luis A. S. V.; Silva, Vitor M.; Silvestre, Joao C.

    1992-08-01

    Almost any frame grabber system has a special controller circuit to transfer data from the video analog to digital converter (ADC) to the system memory. This controller which normally includes a locked phase loop (PLL) and several counters has to fulfill three main functions: the generation of a pixel clock synchronized with the incoming video signal the command of the ADC and memory addressing for the storage of the digitized video. This paper shows how a digital signal processor (DSP) can simplify the design of a video acquisition system by reading the video ADC and writing to its memory at video rates. An example is given with the TM5320C30 processor which supports simultaneous read and write operations on its two external buses. In the case of the CCJR 601 video format the processor runs at 27 MHz. Modern versions of the TMS32OC3O running at as fast as 40 MHz can acquire up to 1066 samples per line. Also the 32-bit wide buses of the processor allows colour acquisition using this technique. In order to build a so simple circuit the DSP needs to be synchronized to the incoming video signal which can be neatly done by using the TMS32OC3O internal timer as part of the PLL. By changing the programming of the internal timer any video format can be grabbed. In addition the DSP can be used as a powerful image

  7. A 2-10 GHz GaAs MMIC opto-electronic phase detector for optical microwave signal generators

    DEFF Research Database (Denmark)

    Bruun, Marlene; Gliese, Ulrik Bo; Petersen, Anders Kongstad

    1994-01-01

    Optical transmission of microwave signals becomes increasingly important. Techniques using beat between optical carriers of semiconductor lasers are promising if efficient optical phase locked loops are realized. A highly efficient GaAs MMIC optoelectronic phase detector for a 2-10 GHz OPLL...

  8. Digital signal processor for silicon audio playback devices; Silicon audio saisei kikiyo digital signal processor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    The digital audio signal processor (DSP) TC9446F series has been developed silicon audio playback devices with a memory medium of, e.g., flash memory, DVD players, and AV devices, e.g., TV sets. It corresponds to AAC (advanced audio coding) (2ch) and MP3 (MPEG1 Layer3), as the audio compressing techniques being used for transmitting music through an internet. It also corresponds to compressed types, e.g., Dolby Digital, DTS (digital theater system) and MPEG2 audio, being adopted for, e.g., DVDs. It can carry a built-in audio signal processing program, e.g., Dolby ProLogic, equalizer, sound field controlling, and 3D sound. TC9446XB has been lined up anew. It adopts an FBGA (fine pitch ball grid array) package for portable audio devices. (translated by NEDO)

  9. IMPLEMENTATION OF A VERILOG-BASED DIGITAL RECEIVER FOR 2.4 GHz ZIGBEE APPLICATIONS ON FPGA

    Directory of Open Access Journals (Sweden)

    RAFIDAH AHMAD

    2014-02-01

    Full Text Available This paper presents the implementation of a digital receiver for 2.4 GHz Zigbee IEEE 802.15.4 applications on a Spartan3E XC3S500E field programmable gate array (FPGA. The proposed digital receiver comprises an offset quadrature phase shift keying (OQPSK demodulator, chip synchronization, and a de-spreading block. A new design method that uses Verilog hardware description language (HDL code through Xilinx ISE version 12 was developed to design these blocks. These blocks were integrated into one top module for optimization. Simulation and measurement were conducted to verify the functionality of the receiver. Implementation results show that the receiver design matched the theoretical expectation. The implementation configuration required up to 22% less slices, flip-flops (FFs, and look-up tables (LUTs than that in previous research. The clock frequencies used were as low as 250 kHz and 2 MHz.

  10. Digital payloads - Enhanced performance through signal processing

    Science.gov (United States)

    Bjornstrom, G.

    A transparent signal-processing payload architecture applicable to mobile communication satellites is introduced, and its features and implementation issues are discussed. In its basic form it is characterized by the formation of a large number of narrowband beams directed at the individual users on ground, and is demonstrated to offer improved transmit power efficiency, frequency-reuse capability and traffic-routing flexibility. The processor implementation is envisaged to make extensive use of digital processing functions and ASIC technology combined with advanced SAW techniques. In addition to its inherent attractive features, this architecture provides many of the benefits of full onboard regeneration and processing while preserving most of the flexibility of conventional analog transponders. Simplified derivatives of the basic configuration that offer reduced processing complexity while preserving the essential advantages gained are also presented. Although initially conceived for FDMA/SCPC-type traffic, the concept can also be adapted to other transmission formats.

  11. High-Capacity Wireless Signal Generation and Demodulation in 75- to 110-GHz Band Employing All-Optical OFDM

    DEFF Research Database (Denmark)

    Zibar, Darko; Sambaraju, Rakesh; Caballero Jambrina, Antonio

    2011-01-01

    We present a radio-frequency (RF) and bit-rate scalable technique for multigigabit wireless signal generation based on all-optical orthogonal frequency-division multiplexing (OFDM) and photonic up-conversion. Coherent detection supported by digital signal processing is used for signal demodulation...

  12. Digital signal processing using virtual instruments

    Science.gov (United States)

    Anderson, James A.; Korrapati, Raghu; Swain, Nikunja K.

    2000-08-01

    The area of test and measurement is changing rapidly because of the recent developments in software and hardware. The test and measurement systems are increasingly becoming PC based. Most of these PC based systems use graphical programming language to design test and measurement modules called virtual instruments (Vis). These Vis provide visual representation of dat or models, and make understanding of abstract concepts and algorithms easier. This allows users to express their ideas in a concise manner. One such virtual instruments package is LabVIEW from National Instruments Corporation at Austin, Texas. This software package is one of the first graphical programming products and is currently used in number of academic institutions, industries, Department of Defense graphical programming products and is currently sued in number of academic institutions, industries, Department of Defense, Department of Energy, and National Aeronautics and Space Administration for various test, measurement, and control applications. LabVIEW has an extensive built-in VI library that can be used to design and develop solutions for different applications. Besides using the built-in VI library that can be used to design and develop solutions for different applications. Besides using the built-in VI modules in LabVIEW, the user can design new VI modules easily. This paper discusses the use of LabVIEW to design and develop digital signal processing VI modules such as Fourier Analysis and Windowing. Instructors can use these modules to teach some of the signal processing concepts effectively.

  13. Digital signal processing for He3 proportional counter

    International Nuclear Information System (INIS)

    Zeynalov, Sh.S.; Ahmadov, Q.S.

    2010-01-01

    Full text : Data acquisition systems for nuclear spectroscopy have traditionally been based on systems with analog shaping amplifiers followed by analog-to-digital converters. Recently, however, new systems based on digital signal processing make possible to replace the analog shaping and timing circuitry the numerical algorithms to derive properties of the pulse such as its amplitude. DSP is a fully numerical analysis of the detector pulse signals and this technique demonstrates significant advantages over analog systems in some circumstances. From a mathematical point of view, one can consider the signal evolution from the detector to the ADC as a sequence of transformations that can be described by precisely defined mathematical expressions. Digital signal processing with ADCs has the possibility to utilize further information on the signal pulses from radiation detectors. In the experiment each step of the signal generation in the 3He filled proportional counter was described using digital signal processing techniques (DSP). The electronic system has consisted of a detector, a preamplifier and a digital oscilloscope. The pulses from the detector were digitized using a digital storage oscilloscope. This oscilloscope allowed signal digitization with accuracy of 8 bit (256 levels) and with frequency of up to 5 * 10 8 samples/s. As a neutron source was used Cf-252. To obtain detector output current pulse I(t) created by the motions of the ions/electrons pairs was written an algorithm which can easily be programmed using modern computer programming languages.

  14. Algorithm for applying interpolation in digital signal processing ...

    African Journals Online (AJOL)

    Software-defined radios and test equipment use a variety of digital signal processing techniques to improve system performance. Interpolation is one technique that can be used to increase the sample rate of digital signals. In this work, we illustrated interpolation in the time domain by writing appropriate codes using ...

  15. A 750MHz and a 8GHz High Bandwidth Digital FFT Spectrometer, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The scope of this project is to to develop a wide bandwidth, low power, and compact single board digital Fast Fourier Transform spectrometer (FFTS) optimized for the...

  16. Analog and digital signal analysis from basics to applications

    CERN Document Server

    Cohen Tenoudji, Frédéric

    2016-01-01

    This book provides comprehensive, graduate-level treatment of analog and digital signal analysis suitable for course use and self-guided learning. This expert text guides the reader from the basics of signal theory through a range of application tools for use in acoustic analysis, geophysics, and data compression. Each concept is introduced and explained step by step, and the necessary mathematical formulae are integrated in an accessible and intuitive way. The first part of the book explores how analog systems and signals form the basics of signal analysis. This section covers Fourier series and integral transforms of analog signals, Laplace and Hilbert transforms, the main analog filter classes, and signal modulations. Part II covers digital signals, demonstrating their key advantages. It presents z and Fourier transforms, digital filtering, inverse filters, deconvolution, and parametric modeling for deterministic signals. Wavelet decomposition and reconstruction of non-stationary signals are also discussed...

  17. Coherent Optical Generation of a 6 GHz Microwave Signal with Directly Phase Locked Semiconductor DFB Lasers

    DEFF Research Database (Denmark)

    Gliese, Ulrik Bo; Nielsen, Torben Nørskov; Bruun, Marlene

    1992-01-01

    of a microwave reference source close to carrier with a noise level of ¿125 dBc/Hz. The total phase variance of the locked carrier is 0.04 rad2 and carriers can be generated in a continuous range from 3 to 18 GHz. The loop reliability is excellent with an average time to cycle slip of 1011 seconds...

  18. Note: A high-frequency signal generator based on direct digital synthesizer and field-programmable gate array

    Science.gov (United States)

    Du, Yuanbo; Li, Wenbing; Ge, Yapeng; Li, Hui; Deng, Ke; Lu, Zehuang

    2017-09-01

    A high-frequency signal generator based on direct digital synthesizer (DDS) and field-programmable gate array (FPGA) is presented. The FPGA provides the controlling time sequence for the DDS, which has a highest output frequency of 1.4 GHz and a frequency resolution of 190 pHz. At an output frequency of 1.2 GHz, the measured phase noise, including the contribution of the reference clock, is -65 dBc/Hz@1 Hz, while the intrinsic phase noise is -82 dBc/Hz@1 Hz. Time delay of the DDS is measured to be less than 150 ns. The signal generator is used to drive an acousto-optic modulator, and the rise time due to the whole link is 24 ns. The developed signal generator can be used in many precision measurement experiments in the fields of atomic, molecular, and optical physics.

  19. Pedagogical reforms of digital signal processing education

    Science.gov (United States)

    Christensen, Michael

    The future of the engineering discipline is arguably predicated heavily upon appealing to the future generation, in all its sensibilities. The greatest burden in doing so, one might rightly believe, lies on the shoulders of the educators. In examining the causal means by which the profession arrived at such a state, one finds that the technical revolution, precipitated by global war, had, as its catalyst, institutions as expansive as the government itself to satisfy the demand for engineers, who, as a result of such an existential crisis, were taught predominantly theoretical underpinnings to address a finite purpose. By contrast, the modern engineer, having expanded upon this vision and adapted to an evolving society, is increasingly placed in the proverbial role of the worker who must don many hats: not solely a scientist, yet often an artist; not a businessperson alone, but neither financially naive; not always a representative, though frequently a collaborator. Inasmuch as change then serves as the only constancy in a global climate, therefore, the educational system - if it is to mimic the demands of the industry - is left with an inherent need for perpetual revitalization to remain relevant. This work aims to serve that end. Motivated by existing research in engineering education, an epistemological challenge is molded into the framework of the electrical engineer with emphasis on digital signal processing. In particular, it is investigated whether students are better served by a learning paradigm that tolerates and, when feasible, encourages error via a medium free of traditional adjudication. Through the creation of learning modules using the Adobe Captivate environment, a wide range of fundamental knowledge in signal processing is challenged within the confines of existing undergraduate courses. It is found that such an approach not only conforms to the research agenda outlined for the engineering educator, but also reflects an often neglected reality

  20. Digital signal processing in power electronics control circuits

    CERN Document Server

    Sozanski, Krzysztof

    2013-01-01

    Many digital control circuits in current literature are described using analog transmittance. This may not always be acceptable, especially if the sampling frequency and power transistor switching frequencies are close to the band of interest. Therefore, a digital circuit is considered as a digital controller rather than an analog circuit. This helps to avoid errors and instability in high frequency components. Digital Signal Processing in Power Electronics Control Circuits covers problems concerning the design and realization of digital control algorithms for power electronics circuits using

  1. Digital signal processing in power system protection and control

    CERN Document Server

    Rebizant, Waldemar; Wiszniewski, Andrzej

    2011-01-01

    Digital Signal Processing in Power System Protection and Control bridges the gap between the theory of protection and control and the practical applications of protection equipment. Understanding how protection functions is crucial not only for equipment developers and manufacturers, but also for their users who need to install, set and operate the protection devices in an appropriate manner. After introductory chapters related to protection technology and functions, Digital Signal Processing in Power System Protection and Control presents the digital algorithms for signal filtering, followed

  2. Detection of the Vibration Signal from Human Vocal Folds Using a 94-GHz Millimeter-Wave Radar

    Directory of Open Access Journals (Sweden)

    Fuming Chen

    2017-03-01

    Full Text Available The detection of the vibration signal from human vocal folds provides essential information for studying human phonation and diagnosing voice disorders. Doppler radar technology has enabled the noncontact measurement of the human-vocal-fold vibration. However, existing systems must be placed in close proximity to the human throat and detailed information may be lost because of the low operating frequency. In this paper, a long-distance detection method, involving the use of a 94-GHz millimeter-wave radar sensor, is proposed for detecting the vibration signals from human vocal folds. An algorithm that combines empirical mode decomposition (EMD and the auto-correlation function (ACF method is proposed for detecting the signal. First, the EMD method is employed to suppress the noise of the radar-detected signal. Further, the ratio of the energy and entropy is used to detect voice activity in the radar-detected signal, following which, a short-time ACF is employed to extract the vibration signal of the human vocal folds from the processed signal. For validating the method and assessing the performance of the radar system, a vibration measurement sensor and microphone system are additionally employed for comparison. The experimental results obtained from the spectrograms, the vibration frequency of the vocal folds, and coherence analysis demonstrate that the proposed method can effectively detect the vibration of human vocal folds from a long detection distance.

  3. Detection of the Vibration Signal from Human Vocal Folds Using a 94-GHz Millimeter-Wave Radar.

    Science.gov (United States)

    Chen, Fuming; Li, Sheng; Zhang, Yang; Wang, Jianqi

    2017-03-08

    The detection of the vibration signal from human vocal folds provides essential information for studying human phonation and diagnosing voice disorders. Doppler radar technology has enabled the noncontact measurement of the human-vocal-fold vibration. However, existing systems must be placed in close proximity to the human throat and detailed information may be lost because of the low operating frequency. In this paper, a long-distance detection method, involving the use of a 94-GHz millimeter-wave radar sensor, is proposed for detecting the vibration signals from human vocal folds. An algorithm that combines empirical mode decomposition (EMD) and the auto-correlation function (ACF) method is proposed for detecting the signal. First, the EMD method is employed to suppress the noise of the radar-detected signal. Further, the ratio of the energy and entropy is used to detect voice activity in the radar-detected signal, following which, a short-time ACF is employed to extract the vibration signal of the human vocal folds from the processed signal. For validating the method and assessing the performance of the radar system, a vibration measurement sensor and microphone system are additionally employed for comparison. The experimental results obtained from the spectrograms, the vibration frequency of the vocal folds, and coherence analysis demonstrate that the proposed method can effectively detect the vibration of human vocal folds from a long detection distance.

  4. Mathematical summary for digital signal processing applications with Matlab

    CERN Document Server

    Gopi, E S

    2010-01-01

    Mathematical Summary for Digital Signal Processing Applications with Matlab consists of Mathematics which is not usually dealt with in the DSP core subject, but used in DSP applications. It gives Matlab programs with illustrations.

  5. Digital signal processor and processing method for GPS receivers

    Science.gov (United States)

    Thomas, Jr., Jess B. (Inventor)

    1989-01-01

    A digital signal processor and processing method therefor for use in receivers of the NAVSTAR/GLOBAL POSITIONING SYSTEM (GPS) employs a digital carrier down-converter, digital code correlator and digital tracking processor. The digital carrier down-converter and code correlator consists of an all-digital, minimum bit implementation that utilizes digital chip and phase advancers, providing exceptional control and accuracy in feedback phase and in feedback delay. Roundoff and commensurability errors can be reduced to extremely small values (e.g., less than 100 nanochips and 100 nanocycles roundoff errors and 0.1 millichip and 1 millicycle commensurability errors). The digital tracking processor bases the fast feedback for phase and for group delay in the C/A, P.sub.1, and P.sub.2 channels on the L.sub.1 C/A carrier phase thereby maintaining lock at lower signal-to-noise ratios, reducing errors in feedback delays, reducing the frequency of cycle slips and in some cases obviating the need for quadrature processing in the P channels. Simple and reliable methods are employed for data bit synchronization, data bit removal and cycle counting. Improved precision in averaged output delay values is provided by carrier-aided data-compression techniques. The signal processor employs purely digital operations in the sense that exactly the same carrier phase and group delay measurements are obtained, to the last decimal place, every time the same sampled data (i.e., exactly the same bits) are processed.

  6. Streamlining digital signal processing a tricks of the trade guidebook

    CERN Document Server

    2012-01-01

    Streamlining Digital Signal Processing, Second Edition, presents recent advances in DSP that simplify or increase the computational speed of common signal processing operations and provides practical, real-world tips and tricks not covered in conventional DSP textbooks. It offers new implementations of digital filter design, spectrum analysis, signal generation, high-speed function approximation, and various other DSP functions. It provides:Great tips, tricks of the trade, secrets, practical shortcuts, and clever engineering solutions from seasoned signal processing professionalsAn assortment.

  7. Digital signal processing for He3 proportional counter

    International Nuclear Information System (INIS)

    Ahmadov, Q.S.; Institute of Radiation Problems, ANAS, Baku

    2011-01-01

    Full text: Data acquisition systems for nuclear spectroscopy have traditionally been based on systems with analog shaping amplifiers followed by analog-to-digital converters. Recently, however, new systems based on digital signal processing allow us to replace the analog shaping and timing circuitry the numerical algorithms to derive properties of the pulse such as its amplitude. DSP is a fully numerical analysis of the detector pulse signals and this technique demonstrates significant advantages over analog systems in some circumstances. From a mathematical point of view, one can consider the signal evolution from the detector to the ADC as a sequence of transformations that can be described by precisely defined mathematical expressions.Digital signal processing with ADCs has the possibility to utilize further information on the signal pulses from radiation detectors [1] [2]. In the experiment each step of the signal generation in the 3He filled proportional counter was described using digital signal processing techniques (DSP). The electronic system has consisted of a detector, a preamplifier and a digital oscilloscope. The pulses from the detector were digitized using a OTSZS-02 (250USB)-4 digital storage oscilloscope from ZAO R UDNEV-SHILYAYEV . This oscilloscope allowed signal digitization with accuracy of 8 bit(256 levels) and with frequency of up to 5.10''8 samples/s. As a neutron source was used Cf-252.To obtain detector output current pulse I(t) created by the motions of the ions/electrons pairs was written an algorithm which can easily be programmed using modern computer programming languages

  8. Digital timing: sampling frequency, anti-aliasing filter and signal interpolation filter dependence on timing resolution

    International Nuclear Information System (INIS)

    Cho, Sanghee; Grazioso, Ron; Zhang Nan; Aykac, Mehmet; Schmand, Matthias

    2011-01-01

    The main focus of our study is to investigate how the performance of digital timing methods is affected by sampling rate, anti-aliasing and signal interpolation filters. We used the Nyquist sampling theorem to address some basic questions such as what will be the minimum sampling frequencies? How accurate will the signal interpolation be? How do we validate the timing measurements? The preferred sampling rate would be as low as possible, considering the high cost and power consumption of high-speed analog-to-digital converters. However, when the sampling rate is too low, due to the aliasing effect, some artifacts are produced in the timing resolution estimations; the shape of the timing profile is distorted and the FWHM values of the profile fluctuate as the source location changes. Anti-aliasing filters are required in this case to avoid the artifacts, but the timing is degraded as a result. When the sampling rate is marginally over the Nyquist rate, a proper signal interpolation is important. A sharp roll-off (higher order) filter is required to separate the baseband signal from its replicates to avoid the aliasing, but in return the computation will be higher. We demonstrated the analysis through a digital timing study using fast LSO scintillation crystals as used in time-of-flight PET scanners. From the study, we observed that there is no significant timing resolution degradation down to 1.3 Ghz sampling frequency, and the computation requirement for the signal interpolation is reasonably low. A so-called sliding test is proposed as a validation tool checking constant timing resolution behavior of a given timing pick-off method regardless of the source location change. Lastly, the performance comparison for several digital timing methods is also shown.

  9. Influence of Signal Stationarity on Digital Stochastic Measurement Implementation

    Directory of Open Access Journals (Sweden)

    Ivan Župunski

    2013-06-01

    Full Text Available The paper presents the influence of signal stationarity on digital stochastic measurement method implementation. The implementation method is based on stochastic voltage generators, analog adders, low resolution A/D converter, and multipliers and accumulators implemented by Field-Programmable Gate Array (FPGA. The characteristic of first implementations of digital stochastic measurement was the measurement of stationary signal harmonics over the constant measurement period. Later, digital stochastic measurement was extended and used also when it was necessary to measure timeseries of non-stationary signal over the variable measurement time. The result of measurement is the set of harmonics, which is, in the case of non-stationary signals, the input for calculating digital values of signal in time domain. A theoretical approach to determine measurement uncertainty is presented and the accuracy trends with varying signal-to-noise ratio (SNR are analyzed. Noisy brain potentials (spontaneous and nonspontaneous are selected as an example of real non-stationary signal and its digital stochastic measurement is tested by simulations and experiments. Tests were performed without noise and with adding noise with SNR values of 10dB, 0dB and - 10dB. The results of simulations and experiments are compared versus theory calculations, and comparasion confirms the theory.

  10. Synthesis of digital locomotive receiver of automatic locomotive signaling

    Directory of Open Access Journals (Sweden)

    K. V. Goncharov

    2013-02-01

    Full Text Available Purpose. Automatic locomotive signaling of continuous type with a numeric coding (ALSN has several disadvantages: a small number of signal indications, low noise stability, high inertia and low functional flexibility. Search for new and more advanced methods of signal processing for automatic locomotive signaling, synthesis of the noise proof digital locomotive receiver are essential. Methodology. The proposed algorithm of detection and identification locomotive signaling codes is based on the definition of mutual correlations of received oscillation and reference signals. For selecting threshold levels of decision element the following criterion has been formulated: the locomotive receiver should maximum set the correct solution for a given probability of dangerous errors. Findings. It has been found that the random nature of the ALSN signal amplitude does not affect the detection algorithm. However, the distribution law and numeric characteristics of signal amplitude affect the probability of errors, and should be considered when selecting a threshold levels According to obtained algorithm of detection and identification ALSN signals the digital locomotive receiver has been synthesized. It contains band pass filter, peak limiter, normalizing amplifier with automatic gain control circuit, analog to digital converter and digital signal processor. Originality. The ALSN system is improved by the way of the transfer of technical means to modern microelectronic element base, more perfect methods of detection and identification codes of locomotive signaling are applied. Practical value. Use of digital technology in the construction of the locomotive receiver ALSN will expand its functionality, will increase the noise immunity and operation stability of the locomotive signal system in conditions of various destabilizing factors.

  11. Unified Digital Periodic Signal Filters for Power Converter Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Xin, Zhen; Zhou, Keliang

    2017-01-01

    Periodic signal controllers like repetitive and resonant controllers have demonstrated much potential in the control of power electronic converters, where periodic signals (e.g., ac voltages and currents) can be precisely regulated to follow references. Beyond the control of periodic signals, ac...... signal processing (e.g., in synchronization and pre-filtering) is also very important for power converter systems. Hence, this paper serves to unify digital periodic signal filters so as to maximize their roles in power converter systems (e.g., enhance the control of ac signals). The unified digital...... periodic signal filters behave like a comb filter, but it can also be configured to selectively filter out the harmonics of interest (e.g., the odd-order harmonics in single-phase power converter systems). Moreover, a virtual variable-sampling-frequency unit delay that enables frequency adaptive periodic...

  12. Digital signal display board design: A knowledge based study

    International Nuclear Information System (INIS)

    Chaitanya, V. Sree Krishna; Rao, C. Raghavendra

    2007-01-01

    The digital signal display board is assumed to be composed of picture tubes for the purpose of displaying characters. The signal board with the picture tubes constitutes an Information System. A methodology for obtaining the discrimable matrix or table (more decisive attributes) and knowledge reduction for the above information system is proposed

  13. eCTG: an automatic procedure to extract digital cardiotocographic signals from digital images.

    Science.gov (United States)

    Sbrollini, Agnese; Agostinelli, Angela; Marcantoni, Ilaria; Morettini, Micaela; Burattini, Luca; Di Nardo, Francesco; Fioretti, Sandro; Burattini, Laura

    2018-03-01

    Cardiotocography (CTG), consisting in the simultaneous recording of fetal heart rate (FHR) and maternal uterine contractions (UC), is a popular clinical test to assess fetal health status. Typically, CTG machines provide paper reports that are visually interpreted by clinicians. Consequently, visual CTG interpretation depends on clinician's experience and has a poor reproducibility. The lack of databases containing digital CTG signals has limited number and importance of retrospective studies finalized to set up procedures for automatic CTG analysis that could contrast visual CTG interpretation subjectivity. In order to help overcoming this problem, this study proposes an electronic procedure, termed eCTG, to extract digital CTG signals from digital CTG images, possibly obtainable by scanning paper CTG reports. eCTG was specifically designed to extract digital CTG signals from digital CTG images. It includes four main steps: pre-processing, Otsu's global thresholding, signal extraction and signal calibration. Its validation was performed by means of the "CTU-UHB Intrapartum Cardiotocography Database" by Physionet, that contains digital signals of 552 CTG recordings. Using MATLAB, each signal was plotted and saved as a digital image that was then submitted to eCTG. Digital CTG signals extracted by eCTG were eventually compared to corresponding signals directly available in the database. Comparison occurred in terms of signal similarity (evaluated by the correlation coefficient ρ, and the mean signal error MSE) and clinical features (including FHR baseline and variability; number, amplitude and duration of tachycardia, bradycardia, acceleration and deceleration episodes; number of early, variable, late and prolonged decelerations; and UC number, amplitude, duration and period). The value of ρ between eCTG and reference signals was 0.85 (P < 10 -560 ) for FHR and 0.97 (P < 10 -560 ) for UC. On average, MSE value was 0.00 for both FHR and UC. No CTG feature

  14. Digital signal processing techniques and applications in radar image processing

    CERN Document Server

    Wang, Bu-Chin

    2008-01-01

    A self-contained approach to DSP techniques and applications in radar imagingThe processing of radar images, in general, consists of three major fields: Digital Signal Processing (DSP); antenna and radar operation; and algorithms used to process the radar images. This book brings together material from these different areas to allow readers to gain a thorough understanding of how radar images are processed.The book is divided into three main parts and covers:* DSP principles and signal characteristics in both analog and digital domains, advanced signal sampling, and

  15. HSP70 expression in human trophoblast cells exposed to different 1.8 Ghz mobile phone signals.

    Science.gov (United States)

    Franzellitti, Silvia; Valbonesi, Paola; Contin, Andrea; Biondi, Carla; Fabbri, Elena

    2008-10-01

    The heat-shock proteins (HSPs) are important cellular stress markers and have been proposed as candidates to infer biological effects of high-frequency electromagnetic fields (EMFs). In the current study, HSP70 gene and protein expression were evaluated in cells of the human trophoblast cell line HTR-8/SVneo after prolonged exposure (4 to 24 h) to 1.8 GHz continuous-wave (CW) and different GSM signals (GSM-217Hz and GSM-Talk) to assess the possible effects of time and modulation schemes on cell responses. Inducible HSP70 protein expression was not modified by high-frequency EMFs under any condition tested. The inducible HSP70A, HSP70B and the constitutive HSC70 transcripts did not change in cells exposed to high-frequency EMFs with the different modulation schemes. Instead, levels of the inducible HSP70C transcript were significantly enhanced after 24 h exposure to GSM-217Hz signals and reduced after 4 and 16 h exposure to GSM-Talk signals. As in other cell systems, in HTR-8/SVneo cells the response to high-frequency EMFs was detected at the mRNA level after exposure to amplitude-modulated GSM signals. The present results suggest that the expression analysis for multiple transcripts, though encoding the same or similar protein products, can be highly informative and may account for subtle changes not detected at the protein level.

  16. A Computer- Based Digital Signal Processing for Nuclear Scintillator Detectors

    International Nuclear Information System (INIS)

    Ashour, M.A.; Abo Shosha, A.M.

    2000-01-01

    In this paper, a Digital Signal Processing (DSP) Computer-based system for the nuclear scintillation signals with exponential decay is presented. The main objective of this work is to identify the characteristics of the acquired signals smoothly, this can be done by transferring the signal environment from random signal domain to deterministic domain using digital manipulation techniques. The proposed system consists of two major parts. The first part is the high performance data acquisition system (DAQ) that depends on a multi-channel Logic Scope. Which is interfaced with the host computer through the General Purpose Interface Board (GPIB) Ver. IEEE 488.2. Also, a Graphical User Interface (GUI) has been designed for this purpose using the graphical programming facilities. The second of the system is the DSP software Algorithm which analyses, demonstrates, monitoring these data to obtain the main characteristics of the acquired signals; the amplitude, the pulse count, the pulse width, decay factor, and the arrival time

  17. Statistical reference criteria for adaptive signal processing in digital communications

    OpenAIRE

    Sala i Álvarez, Josep; Vázquez Grau, Gregorio

    1997-01-01

    A general criterion for the design of adaptive systems in digital communications called the statistical reference criterion is proposed. The criterion is based on imposition of the probability density function of the signal of interest at the output of the adaptive system, with its application to the scenario of highly powerful interferers being the main focus of this paper. The knowledge of the pdf of the wanted signal is used as a discriminator between signals so that i...

  18. Adaptive Noise Suppression Using Digital Signal Processing

    Science.gov (United States)

    Kozel, David; Nelson, Richard

    1996-01-01

    A signal to noise ratio dependent adaptive spectral subtraction algorithm is developed to eliminate noise from noise corrupted speech signals. The algorithm determines the signal to noise ratio and adjusts the spectral subtraction proportion appropriately. After spectra subtraction low amplitude signals are squelched. A single microphone is used to obtain both eh noise corrupted speech and the average noise estimate. This is done by determining if the frame of data being sampled is a voiced or unvoiced frame. During unvoice frames an estimate of the noise is obtained. A running average of the noise is used to approximate the expected value of the noise. Applications include the emergency egress vehicle and the crawler transporter.

  19. Digital signal and image processing using MATLAB

    CERN Document Server

    Blanchet, Gérard

    2006-01-01

    This title provides the most important theoretical aspects of Image and Signal Processing (ISP) for both deterministic and random signals. The theory is supported by exercises and computer simulations relating to real applications.More than 200 programs and functions are provided in the MATLAB® language, with useful comments and guidance, to enable numerical experiments to be carried out, thus allowing readers to develop a deeper understanding of both the theoretical and practical aspects of this subject.

  20. Digital signal processing algorithms for nuclear particle spectroscopy

    International Nuclear Information System (INIS)

    Zejnalova, O.; Zejnalov, Sh.; Hambsch, F.J.; Oberstedt, S.

    2007-01-01

    Digital signal processing algorithms for nuclear particle spectroscopy are described along with a digital pile-up elimination method applicable to equidistantly sampled detector signals pre-processed by a charge-sensitive preamplifier. The signal processing algorithms are provided as recursive one- or multi-step procedures which can be easily programmed using modern computer programming languages. The influence of the number of bits of the sampling analogue-to-digital converter on the final signal-to-noise ratio of the spectrometer is considered. Algorithms for a digital shaping-filter amplifier, for a digital pile-up elimination scheme and for ballistic deficit correction were investigated using a high purity germanium detector. The pile-up elimination method was originally developed for fission fragment spectroscopy using a Frisch-grid back-to-back double ionization chamber and was mainly intended for pile-up elimination in case of high alpha-radioactivity of the fissile target. The developed pile-up elimination method affects only the electronic noise generated by the preamplifier. Therefore the influence of the pile-up elimination scheme on the final resolution of the spectrometer is investigated in terms of the distance between pile-up pulses. The efficiency of the developed algorithms is compared with other signal processing schemes published in literature

  1. Digital signal processing with Matlab examples

    CERN Document Server

    Giron-Sierra, Jose Maria

    2017-01-01

    This is the first volume in a trilogy on modern Signal Processing. The three books provide a concise exposition of signal processing topics, and a guide to support individual practical exploration based on MATLAB programs. This book includes MATLAB codes to illustrate each of the main steps of the theory, offering a self-contained guide suitable for independent study. The code is embedded in the text, helping readers to put into practice the ideas and methods discussed. The book is divided into three parts, the first of which introduces readers to periodic and non-periodic signals. The second part is devoted to filtering, which is an important and commonly used application. The third part addresses more advanced topics, including the analysis of real-world non-stationary signals and data, e.g. structural fatigue, earthquakes, electro-encephalograms, birdsong, etc. The book’s last chapter focuses on modulation, an example of the intentional use of non-stationary signals.

  2. Digital signal and image processing using Matlab

    CERN Document Server

    Blanchet , Gérard

    2015-01-01

    The most important theoretical aspects of Image and Signal Processing (ISP) for both deterministic and random signals, the theory being supported by exercises and computer simulations relating to real applications.   More than 200 programs and functions are provided in the MATLAB® language, with useful comments and guidance, to enable numerical experiments to be carried out, thus allowing readers to develop a deeper understanding of both the theoretical and practical aspects of this subject.  Following on from the first volume, this second installation takes a more practical stance, provi

  3. Digital signal and image processing using MATLAB

    CERN Document Server

    Blanchet , Gérard

    2014-01-01

    This fully revised and updated second edition presents the most important theoretical aspects of Image and Signal Processing (ISP) for both deterministic and random signals. The theory is supported by exercises and computer simulations relating to real applications. More than 200 programs and functions are provided in the MATLABÒ language, with useful comments and guidance, to enable numerical experiments to be carried out, thus allowing readers to develop a deeper understanding of both the theoretical and practical aspects of this subject. This fully revised new edition updates : - the

  4. Inexpensive Digital Monitoring of Signals from a Spectronic-20 Spectrophotometer

    Science.gov (United States)

    Amend, John R.; Morgan, Matthew E.; Whitla, Alex

    2000-02-01

    Obsolete analog-readout vacuum-tube and solid-state Spectronic-20 family spectrophotometers can be found in most college and university chemistry laboratories. While optically these are good single-beam instruments, their electronics package does not permit attachment of recorders or digital displays. This article describes a simple modification that costs less than $10.00 for parts and will permit direct digital readout of the Spectronic-20 signal with a digital voltmeter or a laboratory interface and a computer. When the external plug is removed, the Spectronic-20 reverts to its normal operating mode.

  5. Signals, systems, transforms, and digital signal processing with Matlab

    CERN Document Server

    Corinthios, Michael

    2009-01-01

    Continuous-Time and Discrete-Time Signals and SystemsIntroductionContinuous-Time SignalsPeriodic FunctionsUnit Step FunctionGraphical Representation of FunctionsEven and Odd Parts of a FunctionDirac-Delta ImpulseBasic Properties of the Dirac-Delta ImpulseOther Important Properties of the ImpulseContinuous-Time SystemsCausality, StabilityExamples of Electrical Continuous-Time SystemsMechanical SystemsTransfer Function and Frequency ResponseConvolution and CorrelationA Right-Sided and a Left-Sided FunctionConvolution with an Impulse and Its DerivativesAdditional Convolution PropertiesCorrelation FunctionProperties of the Correlation FunctionGraphical InterpretationCorrelation of Periodic FunctionsAverage, Energy and Power of Continuous-Time SignalsDiscrete-Time SignalsPeriodicityDifference EquationsEven/Odd DecompositionAverage Value, Energy and Power SequencesCausality, StabilityProblemsAnswers to Selected ProblemsFourier Series ExpansionTrigonometric Fourier SeriesExponential Fourier SeriesExponential versus ...

  6. Real-time digital signal processing fundamentals, implementations and applications

    CERN Document Server

    Kuo, Sen M; Tian, Wenshun

    2013-01-01

    Combines both the DSP principles and real-time implementations and applications, and now updated with the new eZdsp USB Stick, which is very low cost, portable and widely employed at many DSP labs. Real-Time Digital Signal Processing introduces fundamental digital signal processing (DSP) principles and will be updated to include the latest DSP applications, introduce new software development tools and adjust the software design process to reflect the latest advances in the field. In the 3rd edition of the book, the key aspect of hands-on experiments will be enhanced to make the DSP principle

  7. Robust digital processing of speech signals

    CERN Document Server

    Kovacevic, Branko; Veinović, Mladen; Marković, Milan

    2017-01-01

    This book focuses on speech signal phenomena, presenting a robustification of the usual speech generation models with regard to the presumed types of excitation signals, which is equivalent to the introduction of a class of nonlinear models and the corresponding criterion functions for parameter estimation. Compared to the general class of nonlinear models, such as various neural networks, these models possess good properties of controlled complexity, the option of working in “online” mode, as well as a low information volume for efficient speech encoding and transmission. Providing comprehensive insights, the book is based on the authors’ research, which has already been published, supplemented by additional texts discussing general considerations of speech modeling, linear predictive analysis and robust parameter estimation.

  8. Digital Signal Processing System for Active Noise Reduction

    Science.gov (United States)

    Edmonson, William W.; Tucker, Jerry

    2002-12-01

    Over the years there has been a need to improve the comfort of passengers in flight. One avenue for increasing comfort is to reduce cabin noise that is attributed to the engine and the vibration of fuselage panels that radiate sound. High frequency noise can be abated using sound absorbing material. Though, for low frequency noise the sound absorption material would have to very thick, thereby reducing the cabin size. To reduce these low frequency disturbances, active noise control systems (ANC) is being developed that utilizes feedback for cancellation of the disturbance. The active noise control system must be small in size, be a low power device, and operate in real-time. It must also be numerically stable i.e. insensitive to temperature and pressure variations. The ANC system will be a module that consists of digital signal processor (DSP), analog-digital and digital-analog converters, power converters, an actuator and sensors. The DSP will implement the feedback control algorithm that controls the actuators. This module will be attached to panels on the inside of the fuselage for actively eliminating resonant modes of the structure caused by turbulent flow across the fuselage Skin. A hardware prototype of the ANC system must be able to eliminate broadband noise consisting of a bandwidth between 100 Hz and 1500 Hz, which requires a sample rate of 5000 Hz. The analog/digital converters output accuracy is 16 bits with a 2's-compliment format and a very short acquisition time. This will also yield the appropriate dynamic range. Similar specifications are required of the digital/analog converter. The processor section of the system integrates a digital signal processor (TI TMS320C33) with analog/digital (Burr-Brown ADS8320) and digital/analog signal (DAC853 1) converters. The converters with associated power conditioning circuitry and test points reside on a daughter board that sits on top of a Spectrum Digital evaluation module. This will have the ability to test

  9. A simple approach to digital signal processing

    CERN Document Server

    Marven, Craig

    1996-01-01

    A readable, understandable introduction to DSP for professionals and students alike . . . This practical guide is a welcome alternative to more complicated introductions to DSP. It assumes no prior DSP experience and takes the reader step-by-step through the most basic signal processing concepts to more complex functions and devices, including sampling, filtering, frequency transforms, data compression, and even DSP design decisions. The guide provides clear, concise explanations and examples, while keeping mathematics to a minimum, to help develop a fundamental understanding of DSP. Other features include: * An extensive resource bibliography of more advanced DSP books. * An example of a typical DSP system development cycle, including tool descriptions. * A complete glossary of DSP-related acronyms Whether you're a working engineer looking into DSP for the first time or an undergraduate struggling to comprehend the subject, this engaging introduction provides easy access to the basic knowledge that will l...

  10. Digital Signal Processing for Optical Coherent Communication Systems

    DEFF Research Database (Denmark)

    Zhang, Xu

    In this thesis, digital signal processing (DSP) algorithms are studied to compensate for physical layer impairments in optical fiber coherent communication systems. The physical layer impairments investigated in this thesis include optical fiber chromatic dispersion, polarization demultiplexing......, light sources frequency and phase offset and phase noise. The studied DSP algorithms are considered as key building blocks in digital coherent receivers for the next generation of optical communication systems such as 112-Gb/s dual polarization (DP) quadrature phase shift keying (QPSK) optical...... spectrum narrowing tolerance 112-Gb/s DP-QPSK optical coherent systems using digital adaptive equalizer. The demonstrated results show that off-line DSP algorithms are able to reduce the bit error rate (BER) penalty induced by signal spectrum narrowing. Third, we also investigate bi...

  11. Digital signaling decouples activation probability and population heterogeneity

    DEFF Research Database (Denmark)

    Kellogg, Ryan A; Tian, Chengzhe; Lipniacki, Tomasz

    2015-01-01

    Digital signaling enhances robustness of cellular decisions in noisy environments, but it is unclear how digital systems transmit temporal information about a stimulus. To understand how temporal input information is encoded and decoded by the NF-κB system, we studied transcription factor dynamics...... and gene regulation under dose- and duration-modulated inflammatory inputs. Mathematical modeling predicted and microfluidic single-cell experiments confirmed that integral of the stimulus (or area, concentration × duration) controls the fraction of cells that activate NF-κB in the population. However...... and uniform dynamics. These results show that digital NF-κB signaling enables multidimensional control of cellular phenotype via input profile, allowing parallel and independent control of single-cell activation probability and population heterogeneity....

  12. Foundations of digital signal processing theory, algorithms and hardware design

    CERN Document Server

    Gaydecki, Patrick

    2005-01-01

    An excellent introductory text, this book covers the basic theoretical, algorithmic and real-time aspects of digital signal processing (DSP). Detailed information is provided on off-line, real-time and DSP programming and the reader is effortlessly guided through advanced topics such as DSP hardware design, FIR and IIR filter design and difference equation manipulation.

  13. Subband coding of digital audio signals without loss of quality

    NARCIS (Netherlands)

    Veldhuis, Raymond N.J.; Breeuwer, Marcel; van de Waal, Robbert

    1989-01-01

    A subband coding system for high quality digital audio signals is described. To achieve low bit rates at a high quality level, it exploits the simultaneous masking effect of the human ear. It is shown how this effect can be used in an adaptive bit-allocation scheme. The proposed approach has been

  14. Digital signal array processor for NSLS booster power supply upgrade

    International Nuclear Information System (INIS)

    Olsen, R.; Dabrowski, J.; Murray, J.

    1993-01-01

    The booster at the NSLS is being upgraded from 0.75 to 2 pulses per second. To accomplish this, new power supplied for the dipole, quadrupole, and sextupole have been installed. This paper will outline the design and function of the digital signal processor used as the primary control element in the power supply control system

  15. Some recent work on lattice structures for digital signal processing

    Indian Academy of Sciences (India)

    Abstract. This paper is concerned with a review of some recent work on derivation and synthesis of lattice structures for digital signal processing (DSP). In particular, synthesis of canonical structures for both finite impulse response (FIR) and infinite impulse response (IIR) transfer functions is presented in detail. This has ...

  16. Digital Implementation of a Duobinary Signalled MSK Demodulator ...

    African Journals Online (AJOL)

    UNISWA Research Journal of Agriculture, Science and Technology. Journal Home ... This paper presents a digital implementation of a demodulator for duobinary signalled Minimum Shift Keying (MSK). A duobinary ... Thus it will be of advantage to employ this demodulator as opposed to its analog counterpart. It is cheaper ...

  17. The study of image processing of parallel digital signal processor

    International Nuclear Information System (INIS)

    Liu Jie

    2000-01-01

    The author analyzes the basic characteristic of parallel DSP (digital signal processor) TMS320C80 and proposes related optimized image algorithm and the parallel processing method based on parallel DSP. The realtime for many image processing can be achieved in this way

  18. Digital Signal Processor System for AC Power Drivers

    Directory of Open Access Journals (Sweden)

    Ovidiu Neamtu

    2009-10-01

    Full Text Available DSP (Digital Signal Processor is the bestsolution for motor control systems to make possible thedevelopment of advanced motor drive systems. The motorcontrol processor calculates the required motor windingvoltage magnitude and frequency to operate the motor atthe desired speed. A PWM (Pulse Width Modulationcircuit controls the on and off duty cycle of the powerinverter switches to vary the magnitude of the motorvoltages.

  19. Novel Orthogonal Signal Based Decomposition of Digital Signals: Application to Sensor Fusion

    Directory of Open Access Journals (Sweden)

    Abdul Faheem Mohed

    2010-03-01

    Full Text Available In this research paper, a novel orthogonal decomposition of an arbitrary “digital” signal is proposed. An approach to attack the problem of wireless sensor fusion using digital signal processing techniques is discussed. The merits of the proposed orthogonal decomposition are briefly discussed. Simulation results are presented to illustrate the effectiveness of the proposed method.

  20. A high speed digital signal averager for pulsed NMR

    International Nuclear Information System (INIS)

    Srinivasan, R.; Ramakrishna, J.; Ra agopalan, S.R.

    1978-01-01

    A 256-channel digital signal averager suitable for pulsed nuclear magnetic resonance spectroscopy is described. It implements 'stable averaging' algorithm and hence provides a calibrated display of the average signal at all times during the averaging process on a CRT. It has a maximum sampling rate of 2.5 μ sec and a memory capacity of 256 x 12 bit words. Number of sweeps is selectable through a front panel control in binary steps from 2 3 to 2 12 . The enhanced signal can be displayed either on a CRT or by a 3.5-digit LED display. The maximum S/N improvement that can be achieved with this instrument is 36 dB. (auth.)

  1. Digital circuit for the introduction and later removal of dither from an analog signal

    Science.gov (United States)

    Borgen, Gary S.

    1994-05-01

    An electronics circuit is presented for accurately digitizing an analog audio or like data signal into a digital equivalent signal by introducing dither into the analog signal and then subsequently removing the dither from the digitized signal prior to its conversion to an analog signal which is a substantial replica of the incoming analog audio or like data signal. The electronics circuit of the present invention is characterized by a first pseudo-random number generator which generates digital random noise signals or dither for addition to the digital equivalent signal and a second pseudo-random number generator which generates subtractive digital random noise signals for the subsequent removal of dither from the digital equivalent signal prior its conversion to the analog replica signal.

  2. Distortions in power spectra of digitized signals - II: Suggested solution

    International Nuclear Information System (INIS)

    Njau, E.C.

    1982-04-01

    In Part I of this report we developed analytical expressions which represent exactly the energy density spectra of ''digitization processes'' that are essentially involved in spectral analysis of continuous signals. Besides, we related the spectral energy density of each digitization process to the parameters of the exact spectral energy density of the corresponding signal. On this basis, we briefly discussed the forms of distortions (or false structures) which are present in normally computed power spectra when the corresponding spectra of the digitization processes are not sufficiently decoupled from or nullified in the computed spectra. The biggest worry with regard to these distortions is not only that they may mask the actual information contained in the original signal, but also they may tempt the researcher to establish false characteristics about the signal involved. It is, in this context, that any reasonable method that could be used (even conditionally) to pinpoint false structures in computed power spectra would be both timely and useful. A simple, handy guidance through which some portions of computed energy density spectra which are dominated by the false structures mentioned above, can be located is presented herein. Equations are presented which give the various frequencies at which false peaks may be located in such ''contaminated'' portions of computed energy density spectra. The occurrence of frequency shifts in computed power spectra is also briefly discussed. (author)

  3. Effects of the exposure to intermittent 1.8 GHz radio frequency electromagnetic fields on HSP70 expression and MAPK signaling pathways in PC12 cells.

    Science.gov (United States)

    Valbonesi, Paola; Franzellitti, Silvia; Bersani, Ferdinando; Contin, Andrea; Fabbri, Elena

    2014-05-01

    We previously reported effects on heat shock protein 70 (HSP70) mRNA expression, a cytoprotective protein induced under stressful condition, in human trophoblast cells exposed to amplitude-modulated Global System for Mobile Communication (GSM) signals. In the present work the same experimental conditions were applied to the rat PC12 cells, in order to assess the stress responses mediated by HSP70 and by the Mitogen Activated Protein Kinases (MAPK) in neuronal-like cells, an interesting model to study possible effects of mobile phone frequencies exposure. HSP70 gene expression level was evaluated by reverse transcriptase polymerase chain reaction, HSP70 protein expression and MAPK phosphorylation were assessed by Western blotting. PC12 cells were exposed for 4, 16 or 24 h to 1.8 GHz continuous wave signal (CW, carrier frequency without modulation) or to two different GSM modulation schemes, GSM-217Hz and GSM-Talk (which generates temporal changes between two different GSM signals, active during talking or listening phases, respectively, thus simulating a typical conversation). Specific adsorption rate (SAR) was 2 W/kg. After PC12 cells exposure to the GSM-217Hz signal for 16 or 24 h, HSP70 transcription significantly increased, whereas no effect was observed in cells exposed to the CW or GSM-Talk signals. HSP70 protein expression and three different MAPK signaling pathways were not affected by the exposure to any of the three different 1.8 GHz signals. The positive effect on HSP70 mRNA expression, observed only in cells exposed to the GSM-217Hz signal, is a repeatable response previously reported in human trophoblast cells and now confirmed in PC12 cells. Further investigations towards a possible role of 1.8 GHz signal modulation are therefore advisable.

  4. Attitude Control of a Satellite by using Digital Signal Processing

    Directory of Open Access Journals (Sweden)

    Adirelle C. Santana

    2012-03-01

    Full Text Available This article has discussed the development of a three-axis attitude digital controller for an artificial satellite using a digital signal processor. The main motivation of this study is the attitude control system of the satellite Multi-Mission Platform, developed by the Brazilian National Institute for Space Research for application in different sort of missions. The controller design was based on the theory of the Linear Quadratic Gaussian Regulator, synthesized from the linearized model of the motion of the satellite, i.e., the kinematics and dynamics of attitude. The attitude actuators considered in this study are pairs of cold gas jets powered by a pulse width/pulse frequency modulator. In the first stage of the project development, a system controller for continuous time was studied with the aim of testing the adequacy of the adopted control. The next steps had included an analysis of discretization techniques, the setting time of sampling rate, and the testing of the digital version of the Linear Quadratic Gaussian Regulator controller in the MATLAB/SIMULINK. To fulfill the study, the controller was implemented in a digital signal processor, specifically the Blackfin BF537 from Analog Devices, along with the pulse width/pulse frequency modulator. The validation tests used a scheme of co-simulation, where the model of the satellite was simulated in MATLAB/SIMULINK, while the controller and modulator were processed in the digital signal processor with a tool called Processor-In-the-Loop, which acted as a data communication link between both environments.function and required time to achieve a given mission accuracy are determined, and results are provided as illustration.

  5. Digital Signal Processing for In-Vehicle Systems and Safety

    CERN Document Server

    Boyraz, Pinar; Takeda, Kazuya; Abut, Hüseyin

    2012-01-01

    Compiled from papers of the 4th Biennial Workshop on DSP (Digital Signal Processing) for In-Vehicle Systems and Safety this edited collection features world-class experts from diverse fields focusing on integrating smart in-vehicle systems with human factors to enhance safety in automobiles. Digital Signal Processing for In-Vehicle Systems and Safety presents new approaches on how to reduce driver inattention and prevent road accidents. The material addresses DSP technologies in adaptive automobiles, in-vehicle dialogue systems, human machine interfaces, video and audio processing, and in-vehicle speech systems. The volume also features: Recent advances in Smart-Car technology – vehicles that take into account and conform to the driver Driver-vehicle interfaces that take into account the driving task and cognitive load of the driver Best practices for In-Vehicle Corpus Development and distribution Information on multi-sensor analysis and fusion techniques for robust driver monitoring and driver recognition ...

  6. CAS - CERN Accelerator School: Course on Digital Signal Processing

    CERN Document Server

    Digital Signal Processing; CAS 2007

    2008-01-01

    These proceedings present the lectures given at the twenty-first specialized course organized by the CERN Accelerator School (CAS), the topic being Digital Signal Processing. The course was held in Sigtuna, Sweden, from 31 May–9 June 2007. This is the first time this topic has been selected for a specialized course. Taking into account the number of related applications currently in use in accelerators around the world, it was recognized that such a topic should definitively be incorporated into the CAS series of specialized courses. The specific aim of the course was to introduce the participants to the use and programming of Digital Signal Processors (DSPs) and Field Programmable Gate Arrays (FPGAs) evaluation boards. The course consisted of lectures in the mornings covering fundamental background knowledge in mathematics, controls theory, design tools, programming hardware platforms, and implementation details. In the afternoons the students split into two groups with people working in pairs. One group w...

  7. Optimal signal-to-noise in digital phase lock amplifiers

    Science.gov (United States)

    Doering, Charles R.; Harvey, Paul M.

    1987-01-01

    An expression for the optimal signal-to-noise ratio for linear phase lock amplifiers is derived. In its digital form the optimal method can be implemented by real-time signal processing techniques. The case of detector-noise-limited systems is analyzed in detail; it is found that the optimal technique can be used to eliminate effectively the detector's time constant from the set of parameters determining the overall efficiency. This has important implications for optical detection system design. Also reported is an experimental verification of the optimal method, thus establishing its practicality.

  8. Expansion of the Eclipse Digital Signal Processing System.

    Science.gov (United States)

    1982-12-01

    the capa- Lility of the AFI’ signal processing laboratory and to make it mor , user-oriented. Three areas--digitizing operations, siqll p)rocess un...ilurrird (Thlcd. Tl’lery aind A ’pplic,- ii ,1 ij;ita 1Siqnal Procossing. Englow wod Cliffs: Pren- -Ii’ .t I c. , 1975. ,). igal T ’ic ,ii ,qy, InC. I

  9. Digital configurable instrument for emulation of signals from radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Abba, A.; Caponio, F.; Geraci, A. [Politecnico di Milano, Department of Electronics, Information and Bioengineering-DEIB, Milan 20133 (Italy)

    2014-01-15

    The paper presents a digital instrument characterized by a specially designed architecture that is able to emulate in real time signals from a generic radiation detection system. The instrument is not a pulse generator of recorded shapes but a synthesizer of random pulses compliant to programmable statistics for height and starting time of events. Completely programmable procedures for emulation of noise, disturbances, and reference level variation are implemented.

  10. A digitally assisted, signal folding neural recording amplifier.

    Science.gov (United States)

    Chen, Yi; Basu, Arindam; Liu, Lei; Zou, Xiaodan; Rajkumar, Ramamoorthy; Dawe, Gavin Stewart; Je, Minkyu

    2014-08-01

    A novel signal folding and reconstruction scheme for neural recording applications that exploits the 1/f(n) characteristics of neural signals is described in this paper. The amplified output is 'folded' into a predefined range of voltages by using comparison and reset circuits along with the core amplifier. After this output signal is digitized and transmitted, a reconstruction algorithm can be applied in the digital domain to recover the amplified signal from the folded waveform. This scheme enables the use of an analog-to-digital convertor with less number of bits for the same effective dynamic range. It also reduces the transmission data rate of the recording chip. Both of these features allow power and area savings at the system level. Other advantages of the proposed topology are increased reliability due to the removal of pseudo-resistors, lower harmonic distortion and low-voltage operation. An analysis of the reconstruction error introduced by this scheme is presented along with a behavioral model to provide a quick estimate of the post reconstruction dynamic range. Measurement results from two different core amplifier designs in 65 nm and 180 nm CMOS processes are presented to prove the generality of the proposed scheme in the neural recording applications. Operating from a 1 V power supply, the amplifier in 180 nm CMOS has a gain of 54.2 dB, bandwidth of 5.7 kHz, input referred noise of 3.8 μVrms and power dissipation of 2.52 μW leading to a NEF of 3.1 in spike band. It exhibits a dynamic range of 66 dB and maximum SNDR of 43 dB in LFP band. It also reduces system level power (by reducing the number of bits in the ADC by 2) as well as data rate to 80% of a conventional design. In vivo measurements validate the ability of this amplifier to simultaneously record spike and LFP signals.

  11. Using a digital signal processor as a data stream controller for digital subtraction angiography

    International Nuclear Information System (INIS)

    Meng, J.D.; Katz, J.E.

    1991-10-01

    High speed, flexibility, and good arithmetic abilities make digital signal processors (DSP) a good choice as input/output controllers for real time applications. The DSP can be made to pre-process data in real time to reduce data volume, to open early windows on what is being acquired and to implement local servo loops. We present an example of a DSP as an input/output controller for a digital subtraction angiographic imaging system. The DSP pre-processes the raw data, reducing data volume by a factor of two, and is potentially capable of producing real-time subtracted images for immediate display

  12. The Signal Validation method of Digital Process Instrumentation System on signal conditioner for SMART

    International Nuclear Information System (INIS)

    Moon, Hee Gun; Park, Sang Min; Kim, Jung Seon; Shon, Chang Ho; Park, Heui Youn; Koo, In Soo

    2005-01-01

    The function of PIS(Process Instrumentation System) for SMART is to acquire the process data from sensor or transmitter. The PIS consists of signal conditioner, A/D converter, DSP(Digital Signal Process) and NIC(Network Interface Card). So, It is fully digital system after A/D converter. The PI cabinet and PDAS(Plant Data Acquisition System) in commercial plant is responsible for data acquisition of the sensor or transmitter include RTD, TC, level, flow, pressure and so on. The PDAS has the software that processes each sensor data and PI cabinet has the signal conditioner, which is need for maintenance and test. The signal conditioner has the potentiometer to adjust the span and zero for test and maintenance. The PIS of SMART also has the signal conditioner which has the span and zero adjust same as the commercial plant because the signal conditioner perform the signal condition for AD converter such as 0∼10Vdc. But, To adjust span and zero is manual test and calibration. So, This paper presents the method of signal validation and calibration, which is used by digital feature in SMART. There are I/E(current to voltage), R/E(resistor to voltage), F/E(frequency to voltage), V/V(voltage to voltage). Etc. In this paper show only the signal validation and calibration about I/E converter that convert level, pressure, flow such as 4∼20mA into signal for AD conversion such as 0∼10Vdc

  13. Applying advanced digital signal processing techniques in industrial radioisotopes applications

    International Nuclear Information System (INIS)

    Mahmoud, H.K.A.E.

    2012-01-01

    Radioisotopes can be used to obtain signals or images in order to recognize the information inside the industrial systems. The main problems of using these techniques are the difficulty of identification of the obtained signals or images and the requirement of skilled experts for the interpretation process of the output data of these applications. Now, the interpretation of the output data from these applications is performed mainly manually, depending heavily on the skills and the experience of trained operators. This process is time consuming and the results typically suffer from inconsistency and errors. The objective of the thesis is to apply the advanced digital signal processing techniques for improving the treatment and the interpretation of the output data from the different Industrial Radioisotopes Applications (IRA). This thesis focuses on two IRA; the Residence Time Distribution (RTD) measurement and the defect inspection of welded pipes using a gamma source (gamma radiography). In RTD measurement application, this thesis presents methods for signal pre-processing and modeling of the RTD signals. Simulation results have been presented for two case studies. The first case study is a laboratory experiment for measuring the RTD in a water flow rig. The second case study is an experiment for measuring the RTD in a phosphate production unit. The thesis proposes an approach for RTD signal identification in the presence of noise. In this approach, after signal processing, the Mel Frequency Cepstral Coefficients (MFCCs) and polynomial coefficients are extracted from the processed signal or from one of its transforms. The Discrete Wavelet Transform (DWT), Discrete Cosine Transform (DCT), and Discrete Sine Transform (DST) have been tested and compared for efficient feature extraction. Neural networks have been used for matching of the extracted features. Furthermore, the Power Density Spectrum (PDS) of the RTD signal has been also used instead of the discrete

  14. Multi-channel nonlinearity compensation of PDM-QPSK signals in dispersion-managed transmission using dispersion-folded digital backward propagation.

    Science.gov (United States)

    Xia, Cen; Liu, Xiang; Chandrasekhar, S; Fontaine, N K; Zhu, Likai; Li, G

    2014-03-10

    We demonstrate nonlinearity compensation of 37.5-GHz-spaced 128-Gb/s PDM-QPSK signals using dispersion-folded digital-backward-propagation and a spectrally-sliced receiver that simultaneously receives three WDM signals, showing mitigation of intra-channel and inter-channel nonlinear effects in a 2560-km dispersion-managed TWRS-fiber link. Intra-channel and adjacent inter-channel nonlinear compensation gains when WDM channels are fully populated in the C-band are estimated based on the GN-model.

  15. A self-starting hybrid optoelectronic oscillator generating ultra low jitter 10-GHz optical pulses and low phase noise electrical signals

    DEFF Research Database (Denmark)

    Lasri, J.; Bilenca, A.; Dahan, D.

    2002-01-01

    In this letter, we describe a self-starting optical pulse source generating ultra low noise 15-ps-wide pulses at 10 GHz. It is based on a hybrid optoelectronic oscillator comprising a fiber extended cavity mode-locked diode laser which injection locks a self-oscillating heterojunction bipolar...... phototransistor. Average jitter levels of 40-43 fs and an amplitude noise of 0.1-0.15% over a frequency range of 500 Hz-15 kHz or 500 Hz-1 MHz were obtained, respectively. The noise is slightly larger, a 57- fs jitter and 0.2% amplitude noise, for a frequency range of 100 Hz-1 MHz. A 10-GHz electrical signal...... with a low phase noise (-108 dBc/Hz at 10-kHz offset from the carrier) is also generated....

  16. Parallel Processing with Digital Signal Processing Hardware and Software

    Science.gov (United States)

    Swenson, Cory V.

    1995-01-01

    The assembling and testing of a parallel processing system is described which will allow a user to move a Digital Signal Processing (DSP) application from the design stage to the execution/analysis stage through the use of several software tools and hardware devices. The system will be used to demonstrate the feasibility of the Algorithm To Architecture Mapping Model (ATAMM) dataflow paradigm for static multiprocessor solutions of DSP applications. The individual components comprising the system are described followed by the installation procedure, research topics, and initial program development.

  17. DSPSR: Digital Signal Processing Software for Pulsar Astronomy

    Science.gov (United States)

    van Straten, W.; Bailes, M.

    2011-01-01

    dspsr is a high-performance, open-source, object-oriented, digital signal processing software library and application suite for use in radio pulsar astronomy. Written primarily in C++, the library implements an extensive range of modular algorithms that can optionally exploit both multiple-core processors and general-purpose graphics processing units. After over a decade of research and development, dspsr is now stable and in widespread use in the community. This paper presents a detailed description of its functionality, justification of major design decisions, analysis of phase-coherent dispersion removal algorithms, and demonstration of performance on some contemporary microprocessor architectures.

  18. Digital signal processing of data from borehole creep closure

    International Nuclear Information System (INIS)

    Chakrabarti, S.; Patrick, W.C.; Duplancic, N.

    1987-01-01

    Digital signal processing, a technique commonly used in the fields of electrical engineering and communication technology, has been successfully used to analyze creep closure data obtained from a 0.91 m diameter by 5.13 deep borehole in bedded salt. By filtering the ''noise'' component of the closure data from a test borehole, important data trends were made more evident and average creep closure rates were able to be calculated. This process provided accurate estimates of closure rates that are used in the design of lined boreholes in which heat-generating transuranic nuclear wastes are emplaced at the Waste Isolation Pilot Plant

  19. Mathematical pattern, smoothing and digital filtering of a speech signal

    International Nuclear Information System (INIS)

    Razzam, Mohamed Habib

    1979-01-01

    After presentation of speech synthesis methods, characterized by a treatment of pre-recorded natural signals, or by an analog simulation of vocal tract, we present a new synthesis method especially based on a mathematical pattern of the signal, as a development of M. RODET's method. For their physiological origin, these signals are partially or totally voiced, or aleatory. For the phoneme voiced parts, we compute the formant curves, the sum of which constitute the wave, directly in time-domain by applying a specific envelope (operating as a time-window analysis) to a sinusoidal wave, The sinusoidal wave computation is made at the beginning of each signal's pseudo-period. The transition from successive periods is assured by a polynomial smoothing followed by a digital filtering. For the aleatory parts, we present an aleatory computation method of formant curves. Each signal is subjected to a melodic diagrams computed in accordance with the nature of the phoneme (vowel or consonant) and its context (isolated or not). (author) [fr

  20. Wireless receiver architectures and design antennas, RF, synthesizers, mixed signal, and digital signal processing

    CERN Document Server

    Rouphael, Tony J

    2014-01-01

    Wireless Receiver Architectures and Design presents the various designs and architectures of wireless receivers in the context of modern multi-mode and multi-standard devices. This one-stop reference and guide to designing low-cost low-power multi-mode, multi-standard receivers treats analog and digital signal processing simultaneously, with equal detail given to the chosen architecture and modulating waveform. It provides a complete understanding of the receiver's analog front end and the digital backend, and how each affects the other. The book explains the design process in great detail, s

  1. 76 FR 38306 - Digital Television Signals Pursuant to the Satellite Home Viewer Extension and Reauthorization...

    Science.gov (United States)

    2011-06-30

    ... Television Signals Pursuant to the Satellite Home Viewer Extension and Reauthorization Act of 2004 AGENCY... Measurement Standards for Digital Television Signals pursuant to the Satellite Home Viewer Extension and... Standards for Digital Television Signals Pursuant to the Satellite Home Viewer Extension and Reauthorization...

  2. 47 CFR 25.144 - Licensing provisions for the 2.3 GHz satellite digital audio radio service.

    Science.gov (United States)

    2010-10-01

    ... system, and the technical, legal, and financial qualifications of the applicant. In particular... receiver that will permit end users to access all licensed satellite DARS systems that are operational or...) Reporting requirements. All licensees of satellite digital audio radio service systems shall, on June 30 of...

  3. The study on the method of image recognition and processing for digital nuclear signals

    International Nuclear Information System (INIS)

    Wang Dongyang; Zhang Ruanyu; Wang Peng; Yan Yangyang; Hao Dejian

    2012-01-01

    Since there are many limits in the method of the traditional DSP system, a new method of digital nuclear signal processing based on the digital image recognition is presented in this paper. This method converts the time-series digital nuclear signal into the pulse image with adjustable pixels. A new principle and method have been taken to develop the SNR of the digital nuclear signal with the theory and method of the digital image processing. A method called ISC is presented, by which it is convenient to extract the template parameters. (authors)

  4. Digital Signal Processing and Control for the Study of Gene Networks

    Science.gov (United States)

    Shin, Yong-Jun

    2016-04-01

    Thanks to the digital revolution, digital signal processing and control has been widely used in many areas of science and engineering today. It provides practical and powerful tools to model, simulate, analyze, design, measure, and control complex and dynamic systems such as robots and aircrafts. Gene networks are also complex dynamic systems which can be studied via digital signal processing and control. Unlike conventional computational methods, this approach is capable of not only modeling but also controlling gene networks since the experimental environment is mostly digital today. The overall aim of this article is to introduce digital signal processing and control as a useful tool for the study of gene networks.

  5. Digital Signal Processing and Control for the Study of Gene Networks.

    Science.gov (United States)

    Shin, Yong-Jun

    2016-04-22

    Thanks to the digital revolution, digital signal processing and control has been widely used in many areas of science and engineering today. It provides practical and powerful tools to model, simulate, analyze, design, measure, and control complex and dynamic systems such as robots and aircrafts. Gene networks are also complex dynamic systems which can be studied via digital signal processing and control. Unlike conventional computational methods, this approach is capable of not only modeling but also controlling gene networks since the experimental environment is mostly digital today. The overall aim of this article is to introduce digital signal processing and control as a useful tool for the study of gene networks.

  6. Improvement of the characterization of ultrasonic data by means of digital signal processing

    International Nuclear Information System (INIS)

    Bieth, M.; Romy, D.; Weigel, D.

    1985-01-01

    The digital signal processing method for averaging using minima developed by Framatome allows to improve signal-to-noise ratio up to 7 dB during ultrasonic testing of cast stainless steel structures (primary pipes of PWR power plants). Application of digital signal processing to industrial testing conditions requires the availability of a fast analog-digital converter capable of real time processings which has been developed by CGR [fr

  7. Method and apparatus for a single channel digital communications system. [synchronization of received PCM signal by digital correlation with reference signal

    Science.gov (United States)

    Couvillon, L. A., Jr.; Carl, C.; Goldstein, R. M.; Posner, E. C.; Green, R. R. (Inventor)

    1973-01-01

    A method and apparatus are described for synchronizing a received PCM communications signal without requiring a separate synchronizing channel. The technique provides digital correlation of the received signal with a reference signal, first with its unmodulated subcarrier and then with a bit sync code modulated subcarrier, where the code sequence length is equal in duration to each data bit.

  8. Optimization of signal processing algorithm for digital beam position monitor

    International Nuclear Information System (INIS)

    Lai Longwei; Yi Xing; Leng Yongbin; Yan Yingbing; Chen Zhichu

    2013-01-01

    Based on turn-by-turn (TBT) signal processing, the paper emphasizes on the optimization of system timing and implementation of digital automatic gain control, slow application (SA) modules. Beam position including TBT, fast application (FA) and SA data can be acquired. On-line evaluation on Shanghai Synchrotron Radiation Facility (SSRF) shows that the processor is able to get the multi-rate position data which contain true beam movements. When the storage ring is 174 mA and 500 bunches filled, the resolutions of TBT data, FA data and SA data achieve 0.84, 0.44 and 0.23 μm respectively. The above results prove that the design could meet the performance requirements. (authors)

  9. Interference and protection of electromagnetic pulse to digital signal processor

    International Nuclear Information System (INIS)

    Wang Yan; Jiao Hongling; He Shanhong; Pan Chao; Feng Deren; Che Wenquan; Xiong Ying

    2013-01-01

    The effective electromagnetic pulse protection is studied in this paper, first the interference of electromagnetic pulse simulator path is analyzed, including the digital signal processor (DSP) and the discharge circuit of coupling interference and net electricity coupling interference. Using the structure optimization design, the hardware block reinforcement measurement and the setting of open software trap, and the watchdog anti-jamming measures, the interference test is completed such as the central processor core voltage of DSP, input/output (I/O) ports of DSP and the display screen. The experimental results show that the combination of hardware and software protection reinforcement technology is effective, and the interference pulse amplitude of DSP board I/O port and the kernel work voltage are reduced, and the interference duration is reduced from 2 μs to 400 ns. The interference pulse is effectively restrained. (authors)

  10. Digital Signal Processing For Low Bit Rate TV Image Codecs

    Science.gov (United States)

    Rao, K. R.

    1987-06-01

    In view of the 56 KBPS digital switched network services and the ISDN, low bit rate codecs for providing real time full motion color video are under various stages of development. Some companies have already brought the codecs into the market. They are being used by industry and some Federal Agencies for video teleconferencing. In general, these codecs have various features such as multiplexing audio and data, high resolution graphics, encryption, error detection and correction, self diagnostics, freezeframe, split video, text overlay etc. To transmit the original color video on a 56 KBPS network requires bit rate reduction of the order of 1400:1. Such a large scale bandwidth compression can be realized only by implementing a number of sophisticated,digital signal processing techniques. This paper provides an overview of such techniques and outlines the newer concepts that are being investigated. Before resorting to the data compression techniques, various preprocessing operations such as noise filtering, composite-component transformation and horizontal and vertical blanking interval removal are to be implemented. Invariably spatio-temporal subsampling is achieved by appropriate filtering. Transform and/or prediction coupled with motion estimation and strengthened by adaptive features are some of the tools in the arsenal of the data reduction methods. Other essential blocks in the system are quantizer, bit allocation, buffer, multiplexer, channel coding etc.

  11. Generation and coherent detection of QPSK signal using a novel method of digital signal processing

    Science.gov (United States)

    Zhao, Yuan; Hu, Bingliang; He, Zhen-An; Xie, Wenjia; Gao, Xiaohui

    2018-02-01

    We demonstrate an optical quadrature phase-shift keying (QPSK) signal transmitter and an optical receiver for demodulating optical QPSK signal with homodyne detection and digital signal processing (DSP). DSP on the homodyne detection scheme is employed without locking the phase of the local oscillator (LO). In this paper, we present an extracting one-dimensional array of down-sampling method for reducing unwanted samples of constellation diagram measurement. Such a novel scheme embodies the following major advantages over the other conventional optical QPSK signal detection methods. First, this homodyne detection scheme does not need strict requirement on LO in comparison with linear optical sampling, such as having a flat spectral density and phase over the spectral support of the source under test. Second, the LabVIEW software is directly used for recovering the QPSK signal constellation without employing complex DSP circuit. Third, this scheme is applicable to multilevel modulation formats such as M-ary PSK and quadrature amplitude modulation (QAM) or higher speed signals by making minor changes.

  12. Kerr Nonlinearity Mitigation: Mid-Link Spectral Inversion Versus Digital Backpropagation in 5×28-GBd PDM 16-QAM Signal Transmission

    DEFF Research Database (Denmark)

    Sackey, Isaac; Da Ros, Francesco; Karl Fischer, Johannes

    2015-01-01

    a dual-pump polarization-independent fiber-optic parametric amplifier and compared to digital backpropagation (DBP) compensation over up to 800-km in a dispersion-managed link. In the single-channel case, the use of the DBP algorithm outperformed the OPC with a Q-factor improvement of 0.9 dB after 800-km......We experimentally investigate Kerr nonlinearity mitigation of a 28-GBd polarization-multiplexed 16-QAM signal in a five-channel 50-GHz spaced wavelength-division multiplexing (WDM) system. Optical phase conjugation (OPC) employing the mid-link spectral inversion technique is implemented by using...

  13. Photonic Ultra-Wideband 781.25-Mb/s Signal Generation and Transmission Incorporating Digital Signal Processing Detection

    DEFF Research Database (Denmark)

    Gibbon, Timothy Braidwood; Yu, Xianbin; Tafur Monroy, Idelfonso

    2009-01-01

    The generation of photonic ultra-wideband (UWB) impulse signals using an uncooled distributed-feedback laser is proposed. For the first time, we experimentally demonstrate bit-for-bit digital signal processing (DSP) bit-error-rate measurements for transmission of a 781.25-Mb/s photonic UWB signal...

  14. CERN Technical Training 2003: Learning for the LHC ! DISP-2003  -  Digital Signal Processing

    CERN Multimedia

    2003-01-01

    DISP-2003 is a two-term course given by CERN and University of Lausanne (UNIL) experts within the framework of the Technical Training Programme. The course will review the current techniques dealing with Digital Signal Processing. The DISP-2003 lecture series is composed of two Terms, and it is intended for an audience who work or will work on digital signal processing aspects, and who need an introductory or refresher/update course. The course will be in English, with questions and answers also in French. Spring 1 Term: DISP-2003: Introduction to Digital Signal Processing 20 February 2003 - 3 April 2003, 7 lectures, Thursdays (attendance cost: 70.- CHF, registration required) Lecturers: Maria Elena Angoletta, AB-BDI; Guy Baribaud, AB-BDI; Philippe Baudrenghien, AB-RF; Laurent Deniau, AT-MTM Programme: 'Classical' digital signal processing. Fourier analysis. The Laplace transform. The z-transform. Digital filters. Statistics for Signal Processing. Signal Estimation and Spectral Analysis. Spring 2 T...

  15. CERN Technical Training 2003: Learning for the LHC ! DISP-2003 - Digital Signal Processing

    CERN Multimedia

    2003-01-01

    DISP-2003 - Digital Signal Processing DISP-2003 is a two-term course given by CERN and University of Lausanne (UNIL) experts within the framework of the Technical Training Programme. The course will review the current techniques dealing with Digital Signal Processing, and it is intended for an audience who work or will work on digital signal processing aspects, and who need an introductory or refresher/update course. The course will be in English, with question and answers also in French. Spring 2 Term: DISP-2003: Advanced Digital Signal Processing 30 April 2003 - 21 May 2003, 4 lectures, Wednesdays afternoon (attendance cost: 40.- CHF, registration required) Lecturers: Léonard Studer, UNIL; Laurent Deniau, AT-MTM; Elena Wildner, AT-MAS Programme: Intelligent signal processing (ISP). Non-linear time series analysis. Image processing. Wavelets. (Basic concepts and definitions have been introduced during the previous Spring 1 Term: DISP-2003: Introduction to Digital Signal Processing). DISP-2003 is open...

  16. Development of Coriolis mass flowmeter with digital drive and signal processing technology.

    Science.gov (United States)

    Hou, Qi-Li; Xu, Ke-Jun; Fang, Min; Liu, Cui; Xiong, Wen-Jun

    2013-09-01

    Coriolis mass flowmeter (CMF) often suffers from two-phase flowrate which may cause flowtube stalling. To solve this problem, a digital drive method and a digital signal processing method of CMF is studied and implemented in this paper. A positive-negative step signal is used to initiate the flowtube oscillation without knowing the natural frequency of the flowtube. A digital zero-crossing detection method based on Lagrange interpolation is adopted to calculate the frequency and phase difference of the sensor output signals in order to synthesize the digital drive signal. The digital drive approach is implemented by a multiplying digital to analog converter (MDAC) and a direct digital synthesizer (DDS). A digital Coriolis mass flow transmitter is developed with a digital signal processor (DSP) to control the digital drive, and realize the signal processing. Water flow calibrations and gas-liquid two-phase flowrate experiments are conducted to examine the performance of the transmitter. The experimental results show that the transmitter shortens the start-up time and can maintain the oscillation of flowtube in two-phase flowrate condition. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  17. A 16 b 2 GHz digital-to-analog converter in 0.18 μm CMOS with digital calibration technology

    International Nuclear Information System (INIS)

    Yang Weidong; Pu Jie; Zhang Ruitao; Chen Chao; Zang Jiandong; Li Tiehu; Luo Pu

    2015-01-01

    This paper presents a 16-bit 2 GSPS digital-to-analog converter (DAC) in 0.18 μm CMOS technology. This DAC is implemented using time division multiplex access system architecture in the digital domain. The input data is received with a two-channel LVDS interface. The DLL technology is introduced to meet the timing requirements between phases of the LVDS data and the data sampling clock. A FIFO is designed to absorb the phase difference between the data clock and DAC system clock. A delay controller is integrated to adjust the phase relationship between the high speed digital clock and analog clock, obtaining a sampling rate of 2 GSPS. The current source mismatch at higher bits is calibrated in the digital domain. Test results show that the DAC achieves 74.02 dBC SFDR at analog output of 36 MHz, and DNL less than ±2.1 LSB and INL less than ±4.3 LSB after the chip is calibrated. (paper)

  18. Multi-stage optical FDM of 12-channel 10-Gb/s data with 20-GHz exact channel spacing using fiber cross-phase modulation with optical subcarrier signals.

    Science.gov (United States)

    Kato, Tomoyuki; Okabe, Ryo; Ludwig, Reinhold; Elschner, Robert; Schubert, Colja; Watanabe, Shigeki

    2011-12-12

    A sequential optical frequency-division multiplexing technique using cross-phase modulation in fibers with exactly frequency-controlled optical subcarrier signals is proposed and demonstrated. 12 channels of 10-Gb/s ASK/DPSK signals with 20-GHz exact channel spacing are successfully multiplexed all-optically at 12 stages with 1-km intervals. © 2011 Optical Society of America

  19. A digital signal processing module for gamma-ray tracking detectors

    International Nuclear Information System (INIS)

    Cromaz, M.; Riot, V.J.; Fallon, P.; Gros, S.; Holmes, B.; Lee, I.Y.; Macchiavelli, A.O.; Vu, C.; Yaver, H.; Zimmermann, S.

    2008-01-01

    We have designed and constructed an 8-channel digital signal processing board for the GRETINA spectrometer. The digitizer samples each of 8 inputs at 100 MHz with 12-bit resolution. Employing a large on-board FPGA, the board derives an energy, leading-edge time, and constant-fraction time from the input signal providing the functionality of a conventional analog electronics system. Readout and control of the digitizer is done over a VME bus. The digitizer's performance met all requirements for processing signals from the GRETINA spectrometer.

  20. The design of pipeline digital signal generator based on VME BUS

    International Nuclear Information System (INIS)

    Wei Shujun; Liu Zhenan; Zhao Dixin; Guo Ya'nan

    2006-01-01

    The paper describes the principle, design and implement of Pipelined digital signal generator based on VME BUS. Furthermore, the paper expands the design in details on how to achieve the complex control with the CPLD. An implementation of Pipelined digital signal generator is provided. (authors)

  1. Method and apparatus for automatically detecting patterns in digital point-ordered signals

    Science.gov (United States)

    Brudnoy, D.M.

    1998-10-20

    The present invention is a method and system for detecting a physical feature of a test piece by detecting a pattern in a signal representing data from inspection of the test piece. The pattern is detected by automated additive decomposition of a digital point-ordered signal which represents the data. The present invention can properly handle a non-periodic signal. A physical parameter of the test piece is measured. A digital point-ordered signal representative of the measured physical parameter is generated. The digital point-ordered signal is decomposed into a baseline signal, a background noise signal, and a peaks/troughs signal. The peaks/troughs from the peaks/troughs signal are located and peaks/troughs information indicating the physical feature of the test piece is output. 14 figs.

  2. Specification for the digital recording of ultrasonic signals (March 1985 revision)

    International Nuclear Information System (INIS)

    Schmitz, V.

    1985-06-01

    This specification describes a precise format for the recording of both digitized ultrasonic signals and the documentation necessary for their interpretation. The specification is a revision of the september 1982 Revision of the 'Specification for the digital recording of ultrasonic signals'. The original document was prepared by an ad hoc committee of EPRI contractors who routinely generate digitized ultrasonic data. This revision includes the use of array probes, mode conversion effects and the possibilities of modern transient recorders

  3. TMS320C25 Digital Signal Processor For 2-Dimensional Fast Fourier Transform Computation

    International Nuclear Information System (INIS)

    Ardisasmita, M. Syamsa

    1996-01-01

    The Fourier transform is one of the most important mathematical tool in signal processing and analysis, which converts information from the time/spatial domain into the frequency domain. Even with implementation of the Fast Fourier Transform algorithms in imaging data, the discrete Fourier transform execution consume a lot of time. Digital signal processors are designed specifically to perform computation intensive digital signal processing algorithms. By taking advantage of the advanced architecture. parallel processing, and dedicated digital signal processing (DSP) instruction sets. This device can execute million of DSP operations per second. The device architecture, characteristics and feature suitable for fast Fourier transform application and speed-up are discussed

  4. Hybrid Optical Fibre-wireless Links at the 75-110 GHz Band Supporting 100 Gbps Transmission Capacities

    DEFF Research Database (Denmark)

    Zibar, Darko; Caballero Jambrina, Antonio; Yu, Xianbin

    2011-01-01

    We present a photonic generation and downconversion method for realizing a 40Gbps wireless link at the 75-110 GHz band exploiting the recent advances in photonic coherent detection technologies and digital signal processing. Furthermore, we analyze the capacities of hybrid optical fiber-wireless ......We present a photonic generation and downconversion method for realizing a 40Gbps wireless link at the 75-110 GHz band exploiting the recent advances in photonic coherent detection technologies and digital signal processing. Furthermore, we analyze the capacities of hybrid optical fiber...

  5. Floating-to-Fixed-Point Conversion for Digital Signal Processors

    Directory of Open Access Journals (Sweden)

    Menard Daniel

    2006-01-01

    Full Text Available Digital signal processing applications are specified with floating-point data types but they are usually implemented in embedded systems with fixed-point arithmetic to minimise cost and power consumption. Thus, methodologies which establish automatically the fixed-point specification are required to reduce the application time-to-market. In this paper, a new methodology for the floating-to-fixed point conversion is proposed for software implementations. The aim of our approach is to determine the fixed-point specification which minimises the code execution time for a given accuracy constraint. Compared to previous methodologies, our approach takes into account the DSP architecture to optimise the fixed-point formats and the floating-to-fixed-point conversion process is coupled with the code generation process. The fixed-point data types and the position of the scaling operations are optimised to reduce the code execution time. To evaluate the fixed-point computation accuracy, an analytical approach is used to reduce the optimisation time compared to the existing methods based on simulation. The methodology stages are described and several experiment results are presented to underline the efficiency of this approach.

  6. Effects of acute exposure to WIFI signals (2.45GHz) on heart variability and blood pressure in Albinos rabbit.

    Science.gov (United States)

    Saili, Linda; Hanini, Amel; Smirani, Chiraz; Azzouz, Ines; Azzouz, Amina; Sakly, Mohsen; Abdelmelek, Hafedh; Bouslama, Zihad

    2015-09-01

    Electrocardiogram and arterial pressure measurements were studied under acute exposures to WIFI (2.45GHz) during one hour in adult male rabbits. Antennas of WIFI were placed at 25cm at the right side near the heart. Acute exposure of rabbits to WIFI increased heart frequency (+22%) and arterial blood pressure (+14%). Moreover, analysis of ECG revealed that WIFI induced a combined increase of PR and QT intervals. By contrast, the same exposure failed to alter maximum amplitude and P waves. After intravenously injection of dopamine (0.50ml/kg) and epinephrine (0.50ml/kg) under acute exposure to RF we found that, WIFI alter catecholamines (dopamine, epinephrine) action on heart variability and blood pressure compared to control. These results suggest for the first time, as far as we know, that exposure to WIFI affect heart rhythm, blood pressure, and catecholamines efficacy on cardiovascular system; indicating that radiofrequency can act directly and/or indirectly on cardiovascular system. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Effects of olive leave extract on metabolic disorders and oxidative stress induced by 2.45 GHz WIFI signals.

    Science.gov (United States)

    Salah, Myriam Ben; Abdelmelek, Hafedh; Abderraba, Manef

    2013-11-01

    We investigated the effect of olive leaves extract administration on glucose metabolism and oxidative response in liver and kidneys of rats exposed to radio frequency (RF). The exposure of rats to RF (2.45 GHz, 1h/day during 21 consecutive days) induced a diabetes-like status. Moreover, RF decreased the activities of glutathione peroxidase (GPx, -33.33% and -49.40%) catalase (CAT, -43.39% and -39.62%) and the superoxide dismutase (SOD, -59.29% and -68.53%) and groups thiol amount (-62.68% and -34.85%), respectively in liver and kidneys. Indeed, exposure to RF increased the malondialdehyde (MDA, 29.69% and 51.35%) concentration respectively in liver and kidneys. Olive leaves extract administration (100 mg/kg, ip) in RF-exposed rats prevented glucose metabolism disruption and restored the activities of GPx, CAT and SOD and thiol group amount in liver and kidneys. Moreover, olive leave extract administration was able to bring down the elevated levels of MDA in liver but not in kidneys. Our investigations suggested that RF exposure induced a diabetes-like status through alteration of oxidative response. Olive leaves extract was able to correct glucose metabolism disorder by minimizing oxidative stress induced by RF in rat tissues. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Digital Signal Processing Techniques for the GIFTS SM EDU

    Science.gov (United States)

    Tian, Jialin; Reisse, Robert A.; Gazarik, Michael J.

    2007-01-01

    The Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) Sensor Module (SM) Engineering Demonstration Unit (EDU) is a high resolution spectral imager designed to measure infrared (IR) radiance using a Fourier transform spectrometer (FTS). The GIFTS instrument employs three Focal Plane Arrays (FPAs), which gather measurements across the long-wave IR (LWIR), short/mid-wave IR (SMWIR), and visible spectral bands. The raw interferogram measurements are radiometrically and spectrally calibrated to produce radiance spectra, which are further processed to obtain atmospheric profiles via retrieval algorithms. This paper describes several digital signal processing (DSP) techniques involved in the development of the calibration model. In the first stage, the measured raw interferograms must undergo a series of processing steps that include filtering, decimation, and detector nonlinearity correction. The digital filtering is achieved by employing a linear-phase even-length FIR complex filter that is designed based on the optimum equiripple criteria. Next, the detector nonlinearity effect is compensated for using a set of pre-determined detector response characteristics. In the next stage, a phase correction algorithm is applied to the decimated interferograms. This is accomplished by first estimating the phase function from the spectral phase response of the windowed interferogram, and then correcting the entire interferogram based on the estimated phase function. In the calibration stage, we first compute the spectral responsivity based on the previous results and the ideal Planck blackbody spectra at the given temperatures, from which, the calibrated ambient blackbody (ABB), hot blackbody (HBB), and scene spectra can be obtained. In the post-calibration stage, we estimate the Noise Equivalent Spectral Radiance (NESR) from the calibrated ABB and HBB spectra. The NESR is generally considered as a measure of the instrument noise performance, and can be estimated as

  9. Distortions in power spectra of digitized signals - I: General formulations

    International Nuclear Information System (INIS)

    Njau, E.C.

    1982-04-01

    When a continuous signal f(t) is digitized and then spectrally analysed, the resultant energy spectral density R(ω) is given as R(ω) = |F(ω) * D(ω)| 2 , where F(ω) is the exact Fourier transform of f(t), D(ω) is the exact Fourier transform of the digitization process and * denotes convolution operation. A notable practical problem in spectral analysis is how to adequately decouple D(ω) from R(ω) and hence obtain the exact energy spectral density of f(t), i.e. |F(ω)| 2 , since R(ω) → |F(ω)| 2 only if D(ω) → delta(ω) or (under certain conditions) when D(ω) → delta(ω-ω 0 ) or if D(ω) → Σsub(n) delta(ω-ωsub(n)), where the latter is a sufficiently spaced series of delta functions and ωsub(j) is constant for a given j. A solution to this problem requires, among others, thorough understanding of D(ω), how it relates to F(ω) and hence the manner or degree to which D(ω) distorts or contaminates F(ω) to form R(ω). In this paper, we have developed exact analytical expressions of D(ω) that are well related to the corresponding F(ω) in the cases when f(t) is a simple sinusoid as well as when it is in the form of a more complex function. It is established that in either of these cases, D(ω) is a clear function of the salient parameters of both f(t) and F(ω). The contents of this paper are used in Part II to examine the manner and extent to which D(ω) causes distortions in R(ω) under given conditions, and also to establish a procedure by which such distortions may be decoupled from a practically computed R(ω). Other related issues such as frequency shifts in computed power spectra are also discussed therein. (author)

  10. A gallium-arsenide digital phase shifter for clock and control signal distribution in high-speed digital systems

    Science.gov (United States)

    Fouts, Douglas J.

    1992-01-01

    The design, implementation, testing, and applications of a gallium-arsenide digital phase shifter and fan-out buffer are described. The integrated circuit provides a method for adjusting the phase of high-speed clock and control signals in digital systems, without the need for pruning cables, multiplexing between cables of different lengths, delay lines, or similar techniques. The phase of signals distributed with the described chip can be dynamically adjusted in eight different steps of approximately 60 ps per step. The IC also serves as a fan-out buffer and provides 12 in-phase outputs. The chip is useful for distributing high-speed clock and control signals in synchronous digital systems, especially if components are distributed over a large physical area or if there is a large number of components.

  11. Method and apparatus for analog signal conditioner for high speed, digital x-ray spectrometer

    International Nuclear Information System (INIS)

    Warburton, W.K.; Hubbard, B.

    1999-01-01

    A signal processing system which accepts input from an x-ray detector-preamplifier and produces a signal of reduced dynamic range for subsequent analog-to-digital conversion is disclosed. The system conditions the input signal to reduce the number of bits required in the analog-to-digital converter by removing that part of the input signal which varies only slowly in time and retaining the amplitude of the pulses which carry information about the x-rays absorbed by the detector. The parameters controlling the signal conditioner's operation can be readily supplied in digital form, allowing it to be integrated into a feedback loop as part of a larger digital x-ray spectroscopy system. 13 figs

  12. Characterization of three digital signal processor systems used in gamma ray spectrometry

    International Nuclear Information System (INIS)

    Reguigui, N.; Morel, J.; Ben Kraiem, H.; Mahjoub, A.

    2002-01-01

    Various manufacturers have recently introduced digital signal processing systems that allow data acquisition in gamma spectrometry at high-input counting rates (several thousand pulses per second). In these systems, the signal digitization is performed immediately following the preamplification stage. This allows digital shaping and filtering of the signal which increases the number of possible combinations in signal shaping and as a consequence, optimizes the resolution as a function of the detector characteristics and the counting rate. Basic characteristic parameters of three digital signal processors that were recently introduced in the market have been studied and compared to those of an analog system. This study is carried out using a hyper-pure coaxial type germanium detector and 57 Co, 60 Co and 137 Cs radioactive sources. Performance parameters such as energy resolution, system throughput, and counting losses that are due to dead time and pile-up effects are presented and discussed

  13. CERN Technical Training 2003: Learning for the LHC! DISP-2003 - Digital Signal Processing

    CERN Multimedia

    2003-01-01

    DISP-2003 is a two-term course given by CERN and University of Lausanne (UNIL) experts within the framework of the Technical Training Programme. The course will review the current techniques dealing with Digital Signal Processing, and it is intended for an audience who work or will work on digital signal processing aspects, and who need an introductory or refresher/update course. The course will be in English, with question and answers also in French. Spring 2 Term: DISP-2003: Advanced Digital Signal Processing 30 April 2003 - 21 May 2003, 4 lectures, Wednesdays afternoon. Attendance cost: 40.- CHF, registration required. Lecturers: Léonard Studer, UNIL; Laurent Deniau, AT-MTM; Elena Wildner, AT-MAS. Programme: Intelligent signal processing (ISP). Non-linear time series analysis. Image processing. Wavelets. Basic concepts and definitions have been introduced during the previous Spring 1 Term: DISP-2003: Introduction to Digital Signal Processing. DISP-2003 is open to all people interested, but registrat...

  14. Digital coherent receiver employing photonic downconversion for phase modulated radio-over-fibre links

    DEFF Research Database (Denmark)

    Zibar, Darko; Caballero Jambrina, Antonio; Guerrero Gonzalez, Neil

    2009-01-01

    A digital coherent receiver employing photonic downconversion is presented and experimentally demonstrated for phase-modulated radio-over-fibre optical links. The receiver is capable of operating at frequencies exceeding the bandwidth of electrical analog-to-digital converter by using photonic...... downconversion to translate the high-frequency input RF signal to the operating frequency range of the analog-to-digital converter. First, using linear digital demodulation scheme we measure SFDR of the link at microwave frequency of 5 GHz. Thereafter, successful signal demodulation of 50 Mbit/s binary phase...... shift keying (BPSK) modulated data signal at 5 GHz RF carrier frequency is experimentally demonstrated by using an analog-to-digital converter with only 1 GHz bandwidth. We successfully demonstrate signal demodulation, using the proposed digital coherent receiver with photonic downconversion, after 40...

  15. Applications of digital signal processors in a gradient controller for MRtomography

    Czech Academy of Sciences Publication Activity Database

    Bartušek, Karel; Dokoupil, Zdeněk; Gescheidtová, E.

    - (2002), s. - ISSN 1213-161X Institutional research plan: CEZ:AV0Z2065902 Keywords : nuclear magnetic resonance * gradient field * digital signal processors Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  16. Study of time-domain digital pulse shaping algorithms for nuclear signals

    International Nuclear Information System (INIS)

    Zhou Jianbin; Tuo Xianguo; Zhu Xing; Liu Yi; Zhou Wei; Lei Jiarong

    2012-01-01

    With the development on high-speed integrated circuit, fast high resolution sampling ADC and digital signal processors are replacing analog shaping amplifier circuit. This paper firstly presents the numerical analysis and simulation on R-C shaping circuit model and C-R shaping circuit model. Mathematic models are established based on 1 st order digital differential method and Kirchhoff Current Law in time domain, and a simulation and error evaluation experiment on an ideal digital signal are carried out with Excel VBA. A digital shaping test for a semiconductor X-ray detector in real time is also presented. Then a numerical analysis for Sallen-Key(S-K) low-pass filter circuit model is implemented based on the analysis of digital R-C and digital C-R shaping methods. By applying the 2 nd order non-homogeneous differential equation,the authors implement a digital Gaussian filter model for a standard exponential-decaying signal and a nuclear pulse signal. Finally, computer simulations and experimental tests are carried out and the results show the possibility of the digital pulse processing algorithms. (authors)

  17. Bispectral methods of signal processing applications in radar, telecommunications and digital image restoration

    CERN Document Server

    Totsky, Alexander V; Kravchenko, Victor F

    2015-01-01

    By studying applications in radar, telecommunications and digital image restoration, this monograph discusses signal processing techniques based on bispectral methods. Improved robustness against different forms of noise as well as preservation of phase information render this method a valuable alternative to common power-spectrum analysis used in radar object recognition, digital wireless communications, and jitter removal in images.

  18. Digital phonocardiographic experiments and signal processing in multidisciplinary fields of university education

    International Nuclear Information System (INIS)

    Nagy, Tamás; Vadai, Gergely; Gingl, Zoltán

    2017-01-01

    Modern measurement of physical signals is based on the use of sensors, electronic signal conditioning, analog-to-digital conversion and digital signal processing carried out by dedicated software. The same signal chain is used in many devices such as home appliances, automotive electronics, medical instruments, and smartphones. Teaching the theoretical, experimental, and signal processing background must be an essential part of improving the standard of higher education, and it fits well to the increasingly multidisciplinary nature of physics and engineering too. In this paper, we show how digital phonocardiography can be used in university education as a universal, highly scalable, exciting, and inspiring laboratory practice and as a demonstration at various levels and complexity. We have developed open-source software templates in modern programming languages to support immediate use and to serve as a basis of further modifications using personal computers, tablets, and smartphones. (paper)

  19. Digital phonocardiographic experiments and signal processing in multidisciplinary fields of university education

    Science.gov (United States)

    Nagy, Tamás; Vadai, Gergely; Gingl, Zoltán

    2017-09-01

    Modern measurement of physical signals is based on the use of sensors, electronic signal conditioning, analog-to-digital conversion and digital signal processing carried out by dedicated software. The same signal chain is used in many devices such as home appliances, automotive electronics, medical instruments, and smartphones. Teaching the theoretical, experimental, and signal processing background must be an essential part of improving the standard of higher education, and it fits well to the increasingly multidisciplinary nature of physics and engineering too. In this paper, we show how digital phonocardiography can be used in university education as a universal, highly scalable, exciting, and inspiring laboratory practice and as a demonstration at various levels and complexity. We have developed open-source software templates in modern programming languages to support immediate use and to serve as a basis of further modifications using personal computers, tablets, and smartphones.

  20. [Development of a digital EEG signal acquiring system based on virtual instrument technology].

    Science.gov (United States)

    Ying, Jun; Chen, Guang-Fei; He, Shi-Lin

    2009-09-01

    This paper introduces an 16-lead digital EEG signal acquisition system, which applies MCU MSP430 as central control unit with high performance analog devices and high speed multi-channel, multi-bit analog-to-digital converter as peripheral to retrench analog circuit. Data is transferred to PC by USART interface. Software on PC based on virtual instrument technology realizes real-time detection, display and storage. The system has many advantages such as high precision, stable performance, small volume and low power dissipation, thus provides a new means for digital EEG signal acquisition.

  1. Digital signals processing using non-linear orthogonal transformation in frequency domain

    Directory of Open Access Journals (Sweden)

    Ivanichenko E.V.

    2017-12-01

    Full Text Available The rapid progress of computer technology in recent decades led to a wide introduction of methods of digital information processing practically in all fields of scientific research. In this case, among various applications of computing one of the most important places is occupied by digital processing systems signals (DSP that are used in data processing remote solution tasks of navigation of aerospace and marine objects, communications, radiophysics, digital optics and in a number of other applications. Digital Signal Processing (DSP is a dynamically developing an area that covers both technical and software tools. Related areas for digital signal processing are theory information, in particular, the theory of optimal signal reception and theory pattern recognition. In the first case, the main problem is signal extraction against a background of noise and interference of a different physical nature, and in the second - automatic recognition, i.e. classification and signal identification. In the digital processing of signals under a signal, we mean its mathematical description, i.e. a certain real function, containing information on the state or behavior of a physical system under an event that can be defined on a continuous or discrete space of time variation or spatial coordinates. In the broad sense, DSP systems mean a complex algorithmic, hardware and software. As a rule, systems contain specialized technical means of preliminary (or primary signal processing and special technical means for secondary processing of signals. Means of pretreatment are designed to process the original signals observed in general case against a background of random noise and interference of a different physical nature and represented in the form of discrete digital samples, for the purpose of detecting and selection (selection of the useful signal and evaluation characteristics of the detected signal. A new method of digital signal processing in the frequency

  2. Output Width Signal Control In Asynchronous Digital Systems Using Monostabil Circuits

    Directory of Open Access Journals (Sweden)

    Mihai Timis

    2006-01-01

    Full Text Available . In present paper, I propose a method for resolving the timing delays for output signals from an asynchronous sequential system. It will be used an example of an asynchronous sequential system that will set up an output signal when an input signal will be set up. The width of the output signal depends on the input signal width, and in this case it is very short. There are many synthesis methods, like using a RC group system, a monostabil system in design of the asynchronous digital system or using an external clock signal, CK. In this paper will be used a monostabil circuit.

  3. SCOTT: A time and amplitude digitizer ASIC for PMT signal processing

    Science.gov (United States)

    Ferry, S.; Guilloux, F.; Anvar, S.; Chateau, F.; Delagnes, E.; Gautard, V.; Louis, F.; Monmarthe, E.; Le Provost, H.; Russo, S.; Schuller, J.-P.; Stolarczyk, Th.; Vallage, B.; Zonca, E.; KM3NeT Consortium

    2013-10-01

    SCOTT is an ASIC designed for the readout electronics of photomultiplier tubes developed for KM3NeT, the cubic-kilometer scale neutrino telescope in Mediterranean Sea. To digitize the PMT signals, the multi-time-over-threshold technique is used with up to 16 adjustable thresholds. Digital outputs of discriminators feed a circular sampling memory and a “first in first out” digital memory. A specific study has shown that five specifically chosen thresholds are suited to reach the required timing accuracy. A dedicated method based on the duration of the signal over a given threshold allows an equivalent timing precision at any charge. To verify that the KM3NeT requirements are fulfilled, this method is applied on PMT signals digitized by SCOTT.

  4. Improving RF Transmit Power and Received Signal Strength in 2.4 GHz ZigBee Based Active RFID System with Embedded Method

    Science.gov (United States)

    Po'ad, F. A.; Ismail, W.; Jusoh, J. F.

    2017-08-01

    This paper describes the experiments and analysis conducted on 2.4 GHz embedded active Radio Frequency Identification (RFID) - Wireless Sensor Network (WSN) based system that has been developed for the purposes of location tracking and monitoring in indoor and outdoor environments. Several experiments are conducted to test the effectiveness and performance of the developed system and two of them is by measuring the Radio Frequency (RF) transmitting power and Received Signal Strength (RSS) to prove that the embedded active RFID tag is capable to generate higher transmit power during data transmission and able to provide better RSS reading compared to standalone RFID tag. Experiments are carried out on two RFID tags which are active RFID tag embedded with GPS and GSM (ER2G); and standalone RFID tag communicating with the same active RFID reader. The developed ER2G contributes 12.26 % transmit power and 6.47 % RSS reading higher than standalone RFID tag. The results conclude that the ER2G gives better performance compared to standalone RFID tag and can be used as guidelines for future design improvements.

  5. Whole body exposure to 2.4 GHz WIFI signals: effects on cognitive impairment in adult triple transgenic mouse models of Alzheimer's disease (3xTg-AD).

    Science.gov (United States)

    Banaceur, Sana; Banasr, Sihem; Sakly, Mohsen; Abdelmelek, Hafedh

    2013-03-01

    The present investigation aimed at evaluating the effects of long-term exposure to WIFI type radiofrequency (RF) signals (2.40 GHz), two hours per day during one month at a Specific Absorption Rate (SAR) of 1.60 W/kg. The effects of RF exposure were studied on wildtype mice and triple transgenic mice (3xTg-AD) destined to develop Alzheimer's-like cognitive impairment. Mice were divided into four groups: two sham groups (WT, TG; n=7) and two exposed groups (WTS, TGS; n=7). The cognitive interference task used in this study was designed from an analogous human cognitive interference task including the Flex field activity system test, the two-compartment box test and the Barnes maze test. Our data demonstrate for the first time that RF improves cognitive behavior of 3xTg-AD mice. We conclude that RF exposure may represent an effective memory-enhancing approach in Alzheimer's disease. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Implementation of a Digital Signal Processing Subsystem for a Long Wavelength Array Station

    Science.gov (United States)

    Soriano, Melissa; Navarro, Robert; D'Addario, Larry; Sigman, Elliott; Wang, Douglas

    2011-01-01

    This paper describes the implementation of a Digital Signal Processing (DP) subsystem for a single Long Wavelength Array (LWA) station.12 The LWA is a radio telescope that will consist of many phased array stations. Each LWA station consists of 256 pairs of dipole-like antennas operating over the 10-88 MHz frequency range. The Digital Signal Processing subsystem digitizes up to 260 dual-polarization signals at 196 MHz from the LWA Analog Receiver, adjusts the delay and amplitude of each signal, and forms four independent beams. Coarse delay is implemented using a first-in-first-out buffer and fine delay is implemented using a finite impulse response filter. Amplitude adjustment and polarization corrections are implemented using a 2x2 matrix multiplication

  7. Low-frequency analog signal distribution on digital photonic networks by optical delta-sigma modulation

    Science.gov (United States)

    Kanno, Atsushi; Kawanishi, Tetsuya

    2013-12-01

    We propose a delta-sigma modulation scheme for low- and medium-frequency signal transmission in a digital photonic network system. A 10-Gb/s-class optical transceiver with a delta-sigma modulator utilized as a high-speed analog-to-digital converter (ADC) provides a binary optical signal. On the signal reception side, a low-cost and slow-speed photonic receiver directly converts the binary signal into an analog signal at frequencies from several hundreds of kilohertz several tens of megahertz. Further, by using a clock and data recovery circuit at the receiver to reduce jitters, the single-sideband phase noise of the generated signals can be significantly reduced.

  8. Fast modified signal-digit (MSD) multiplication technology and system

    Science.gov (United States)

    Sun, DeGui; He, Li-Ming; Wang, Na-Xin; Weng, Zhao-Heng

    1994-06-01

    In this paper, the carry-free property of modified-signed-digit (MSD) addition is analyzed with a space position logic encoding scheme. On this basis, MSD multiplication is discussed and a fast MSD multiplication system composed of optoelectronic logic technology and a multilayer optical interconnection architecture is propsed and studied. Finally, the effectivity of the fast MSD multiplication system is demostrated by using a 2X2 bit multiplication example and experimental results are given.

  9. Reconfigurable signal processor designs for advanced digital array radar systems

    Science.gov (United States)

    Suarez, Hernan; Zhang, Yan (Rockee); Yu, Xining

    2017-05-01

    The new challenges originated from Digital Array Radar (DAR) demands a new generation of reconfigurable backend processor in the system. The new FPGA devices can support much higher speed, more bandwidth and processing capabilities for the need of digital Line Replaceable Unit (LRU). This study focuses on using the latest Altera and Xilinx devices in an adaptive beamforming processor. The field reprogrammable RF devices from Analog Devices are used as analog front end transceivers. Different from other existing Software-Defined Radio transceivers on the market, this processor is designed for distributed adaptive beamforming in a networked environment. The following aspects of the novel radar processor will be presented: (1) A new system-on-chip architecture based on Altera's devices and adaptive processing module, especially for the adaptive beamforming and pulse compression, will be introduced, (2) Successful implementation of generation 2 serial RapidIO data links on FPGA, which supports VITA-49 radio packet format for large distributed DAR processing. (3) Demonstration of the feasibility and capabilities of the processor in a Micro-TCA based, SRIO switching backplane to support multichannel beamforming in real-time. (4) Application of this processor in ongoing radar system development projects, including OU's dual-polarized digital array radar, the planned new cylindrical array radars, and future airborne radars.

  10. Study on the method of digital signals processing for acquiring nuclear energy spectrum

    International Nuclear Information System (INIS)

    Zhang Ruanyu; Chen Shiguo; Luo Xiaobing; Wang Peng; Li Taihua

    2004-01-01

    A method of digital nuclear radiation energy signals processing was developed. It includes polar-zero identifier and compensation, baseline subtraction, low-pass filter, pulse shaping and amplitude analyses. The method can convert a signal with long exponential attenuating tail to a trapezoidal or triangular pulse. Processing the signal in off-line, the preliminary experimental tests show the potential advantages of these techniques in high resolution spectroscopy. (author)

  11. Digital pulse shape discrimination

    International Nuclear Information System (INIS)

    Miller, L. F.; Preston, J.; Pozzi, S.; Flaska, M.; Neal, J.

    2007-01-01

    Pulse-shape discrimination (PSD) has been utilised for about 40 years as a method to obtain estimates for dose in mixed neutron and photon fields. Digitizers that operate close to GHz are currently available at a reasonable cost, and they can be used to directly sample signals from photomultiplier tubes. This permits one to perform digital PSD rather than the traditional, and well-established, analogous techniques. One issue that complicates PSD for neutrons in mixed fields is that the light output characteristics of typical scintillators available for PSD, such as BC501A, vary as a function of energy deposited in the detector. This behaviour is more easily accommodated with digital processing of signals than with analogous signal processing. Results illustrate the effectiveness of digital PSD. (authors)

  12. Hybrid digital signal processing and neural networks applications in PWRs

    International Nuclear Information System (INIS)

    Eryurek, E.; Upadhyaya, B.R.; Kavaklioglu, K.

    1991-01-01

    Signal validation and plant subsystem tracking in power and process industries require the prediction of one or more state variables. Both heteroassociative and auotassociative neural networks were applied for characterizing relationships among sets of signals. A multi-layer neural network paradigm was applied for sensor and process monitoring in a Pressurized Water Reactor (PWR). This nonlinear interpolation technique was found to be very effective for these applications

  13. Design and implementation of a multiband digital filter using FPGA to extract the ECG signal in the presence of different interference signals.

    Science.gov (United States)

    Aboutabikh, Kamal; Aboukerdah, Nader

    2015-07-01

    In this paper, we propose a practical way to synthesize and filter an ECG signal in the presence of four types of interference signals: (1) those arising from power networks with a fundamental frequency of 50Hz, (2) those arising from respiration, having a frequency range from 0.05 to 0.5Hz, (3) muscle signals with a frequency of 25Hz, and (4) white noise present within the ECG signal band. This was done by implementing a multiband digital filter (seven bands) of type FIR Multiband Least Squares using a digital programmable device (Cyclone II EP2C70F896C6 FPGA, Altera), which was placed on an education and development board (DE2-70, Terasic). This filter was designed using the VHDL language in the Quartus II 9.1 design environment. The proposed method depends on Direct Digital Frequency Synthesizers (DDFS) designed to synthesize the ECG signal and various interference signals. So that the synthetic ECG specifications would be closer to actual ECG signals after filtering, we designed in a single multiband digital filter instead of using three separate digital filters LPF, HPF, BSF. Thus all interference signals were removed with a single digital filter. The multiband digital filter results were studied using a digital oscilloscope to characterize input and output signals in the presence of differing sinusoidal interference signals and white noise. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. A digital signal processor based rf control system for the TRIUMF ISAC RFQ prototype

    International Nuclear Information System (INIS)

    Fong, K.; Fang, S.; Laverty, M.

    1996-01-01

    A stand alone digital signal processor is used to control the RFQ prototype in the TRIUMF ISAC development program. The advantage of a digital control system over the traditional analogue system is that it offers the higher degree of flexibility necessary for a development system. For this application the system is designed to have the outward appearance of an analogue system, and uses dials, knobs, and switches as the operator interface. The digital signal processor is used as a feedback controller during CW rf operation, with the feedback gain parameters continually adjustable. It is also able to perform the same regulation during pulsed operation, with additional feedforward compensation for initial pulse on duration. Using a low cost analogue-to-digital converter with a sample rate of 100 kHz, a regulation bandwidth of 10 kHz is achieved. (author)

  15. Digitizing high frequency signals using serial analog memories

    International Nuclear Information System (INIS)

    Coonrod, J.W.

    1975-10-01

    An online computer system has been developed as a replacement for oscilloscopes and cameras on the Tormac project. Up to 32 simultaneous waveforms are recorded at up to 2 MHz in analog shift registers, then digitized sequentially after the event into a small PDP-11 computer. Data and functions of data may be displayed or plotted locally, and then forwarded for storage at a larger, remote computer via a network arrangement. Advantages over scopes have been lower incremental cost (approximately $200/channel), less noise pickup, better resolution (less than 1%), and immediate presentation of data

  16. Digital generation of stochastic signals of arbitrary spectral shape

    International Nuclear Information System (INIS)

    Behringer, K.; Nishihara, H.; Spiekerman, G.

    1986-10-01

    For computer-simulation experiments in the development of noise monitoring systems three methods of generating ergodic Gaussian random noise with specified spectral properties have been investigated: digital filtering of white noise optimum symmetric FIR filters, a modified Rice formulation and an approximation of the Kac representation of noise. The proposed modified Rice formulation is a new noise generation method which is most efficient with regard to the computation time. By windowing subsequent Rice sequences a smooth noise record of any desired length can be produced. (author)

  17. Digital signal processing for wireless communication using Matlab

    CERN Document Server

    Gopi, E S

    2016-01-01

    This book examines signal processing techniques used in wireless communication illustrated by using the Matlab program. The author discusses these techniques as they relate to Doppler spread; delay spread; Rayleigh and Rician channel modeling; rake receiver; diversity techniques; MIMO and OFDM -based transmission techniques; and array signal processing. Related topics such as detection theory, link budget, multiple access techniques, and spread spectrum are also covered.   ·         Illustrates signal processing techniques involved in wireless communication using Matlab ·         Discusses multiple access techniques such as Frequency division multiple access, Time division multiple access, and Code division multiple access ·         Covers band pass modulation techniques such as Binary phase shift keying, Differential phase shift keying, Quadrature phase shift keying, Binary frequency shift keying, Minimum shift keying, and Gaussian minimum shift keying.

  18. 154 GHz collective Thomson scattering in LHD

    Science.gov (United States)

    Tanaka, K.; Nishiura, M.; Kubo, S.; Shimozuma, T.; Saito, T.; Moseev, D.; Abramovic, I.

    2018-01-01

    Collective Thomson scattering (CTS) was developed by using a 154 GHz gyrotron, and the first data has been obtained. Already, 77 GHz CTS has worked successfully. However, in order to access higher density region, 154 GHz option enhances the usability that reduces the refraction effect, which deteriorates in the local measurements. The system in the down converted frequency was almost identical to the system for 77 GHz. Probing beam, a notch filter, a mixer, and a local oscillator in the receiver system for 77 GHz option were replaced to those for the 154 GHz option. 154 GHz gyrotron was originally prepared for the second harmonic electron cyclotron heating (ECRH) at 2.75 T. However, scattering signal was masked by the second harmonic electron cyclotron emission (ECE) at 2.75 T. Therefore, 154 GHz CTS was operated at 1.375 T with fourth harmonic ECE, and an acceptable signal to noise ratio was obtained. There is a signature of fast ion components with neutral beam (NB) injection. In addition, the CTS spectrum became broader in hydrogen discharge than in deuterium discharge, as the theoretical CTS spectrum expects. This observation indicates a possibility to identify ion species ratio by the 154 GHz CTS diagnostic.

  19. Advanced signaling technologies for high-speed digital fiber-optic links.

    Science.gov (United States)

    Stark, Andrew J; Isautier, Pierre; Pan, Jie; Pavan, Sriharsha Kota; Filer, Mark; Tibuleac, Sorin; Lingle, Robert; de Salvo, Richard; Ralph, Stephen E

    2014-09-01

    We summarize the most recent research of the Georgia Tech Terabit Optical Networking Consortium and the state-of-the-art in fiber telecommunications. These results comprise high-capacity single-mode fiber systems with digital coherent receivers and shorter-reach multimode fiber links with vertical cavity surface emitting lasers. We strongly emphasize the capabilities that sophisticated digital signal processing and electronics add to these fiber-based data transport links.

  20. Experience With Sampling Of 500 MHz Rf Signal For Digital Receiver Applications

    CERN Document Server

    Mavric, U; Ursic, R

    2003-01-01

    This article will present test results of a prototype system that was built to evaluate feasibility of a direct sampling of a 500 MHz RF signal for use in digital receiver applications. The system consists of a variable gain RF front end, a fast analog to digital converter (ADC) and a field programmable gate array (FPGA) providing glue-logic between the ADC and a PC computer.

  1. The digital traces of bubbles: Feedback cycles between socio-economic signals in the Bitcoin economy

    OpenAIRE

    Garcia David; Tessone Claudio Juan; Mavrodiev Pavlin; Perony Nicolas

    2014-01-01

    What is the role of social interactions in the creation of price bubbles? Answering this question requires obtaining collective behavioural traces generated by the activity of a large number of actors. Digital currencies offer a unique possibility to measure socio-economic signals from such digital traces. Here, we focus on Bitcoin, the most popular cryptocurrency. Bitcoin has experienced periods of rapid increase in exchange rates (price) followed by sharp decline; we hypothesise that these ...

  2. Digital Signal Processing State-of-the-Art at CERN and Recommendations

    CERN Document Server

    Angoletta, Maria Elena; Peschardt, E; Serrano, J

    2002-01-01

    Dramatic hardware performance improvements over the last decades have paved the way to the ascent of digital techniques for processing signals, with a concurrent and parallel interest in Digital Signal Processing (DSPing) and in the use of Digital Signal Processors (DSPs). Recent discussions within PS showed that there are needs for DSP-qualified manpower in new projects that cannot be fully satisfied internally. In order to determine how PS can best profit from the growing importance and efficiency of DSP technologies, with an effort compatible with the available divisional resources, a DSP working group was created. Its mandate is to advise PS management on the best way to proceed in the DSPs and DSPing domains. In particular, the issues targeted are wide-ranging, from evaluating the state-of-the-art at CERN to hardware standardisation and required training. This report gives the findings of the working group and presents its closing recommendations.

  3. Digital Signal Processing Applied to the Modernization Of Polish Navy Sonars

    Directory of Open Access Journals (Sweden)

    Marszal Jacek

    2014-04-01

    Full Text Available The article presents the equipment and digital signal processing methods used for modernizing the Polish Navy’s sonars. With the rapid advancement of electronic technologies and digital signal processing methods, electronic systems, including sonars, become obsolete very quickly. In the late 1990s a team of researchers of the Department of Marine Electronics Systems, Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology, began work on modernizing existing sonar systems for the Polish Navy. As part of the effort, a methodology of sonar modernization was implemented involving a complete replacement of existing electronic components with newly designed ones by using bespoke systems and methods of digital signal processing. Large and expensive systems of ultrasound transducers and their dipping and stabilisation systems underwent necessary repairs but were otherwise left unchanged. As a result, between 2001 and 2014 the Gdansk University of Technology helped to modernize 30 sonars of different types.

  4. Distortion-Free 1-Bit PWM Coding for Digital Audio Signals

    Directory of Open Access Journals (Sweden)

    John Mourjopoulos

    2007-01-01

    Full Text Available Although uniformly sampled pulse width modulation (UPWM represents a very efficient digital audio coding scheme for digital-to-analog conversion and full-digital amplification, it suffers from strong harmonic distortions, as opposed to benign non-harmonic artifacts present in analog PWM (naturally sampled PWM, NPWM. Complete elimination of these distortions usually requires excessive oversampling of the source PCM audio signal, which results to impractical realizations of digital PWM systems. In this paper, a description of digital PWM distortion generation mechanism is given and a novel principle for their minimization is proposed, based on a process having some similarity to the dithering principle employed in multibit signal quantization. This conditioning signal is termed “jither” and it can be applied either in the PCM amplitude or the PWM time domain. It is shown that the proposed method achieves significant decrement of the harmonic distortions, rendering digital PWM performance equivalent to that of source PCM audio, for mild oversampling (e.g., ×4 resulting to typical PWM clock rates of 90 MHz.

  5. Distortion-Free 1-Bit PWM Coding for Digital Audio Signals

    Directory of Open Access Journals (Sweden)

    Mourjopoulos John

    2007-01-01

    Full Text Available Although uniformly sampled pulse width modulation (UPWM represents a very efficient digital audio coding scheme for digital-to-analog conversion and full-digital amplification, it suffers from strong harmonic distortions, as opposed to benign non-harmonic artifacts present in analog PWM (naturally sampled PWM, NPWM. Complete elimination of these distortions usually requires excessive oversampling of the source PCM audio signal, which results to impractical realizations of digital PWM systems. In this paper, a description of digital PWM distortion generation mechanism is given and a novel principle for their minimization is proposed, based on a process having some similarity to the dithering principle employed in multibit signal quantization. This conditioning signal is termed "jither" and it can be applied either in the PCM amplitude or the PWM time domain. It is shown that the proposed method achieves significant decrement of the harmonic distortions, rendering digital PWM performance equivalent to that of source PCM audio, for mild oversampling (e.g., resulting to typical PWM clock rates of 90 MHz.

  6. Joint time frequency analysis in digital signal processing

    DEFF Research Database (Denmark)

    Pedersen, Flemming

    with this technique is that the resolution is limited because of distortion. To overcome the resolution limitations of the Fourier Spectogram, many new distributions have been developed. In spite of this the Fourier Spectogram is by far the prime method for the analysis of signals whose spectral content is varying...

  7. Effects of prenatal exposure to WIFI signal (2.45GHz) on postnatal development and behavior in rat: Influence of maternal restraint.

    Science.gov (United States)

    Othman, Haifa; Ammari, Mohamed; Sakly, Mohsen; Abdelmelek, Hafedh

    2017-05-30

    The present study was carried out to investigate the potential combined influence of maternal restraint stress and 2.45GHz WiFi signal exposure on postnatal development and behavior in the offspring of exposed rats. 24 pregnant albino Wistar rats were randomly assigned to four groups: Control, WiFi-exposed, restrained and both WiFi-exposed and restrained groups. Each of WiFi exposure and restraint occurred 2h/day along gestation till parturition. The pups were evaluated for physical development and neuromotor maturation. Moreover, elevated plus maze test, open field activity and stationary beam test were also determined on postnatal days 28, 30 and 31, respectively. After behavioral tests, the rats were anesthetized and their brains were removed for biochemical analysis. Our main findings showed no detrimental effects on gestation progress and outcomes at delivery in all groups. Subsequently, WiFi and restraint, per se and mainly in concert altered physical development of pups with slight differences between genders. Behaviorally, the gestational WiFi irradiation, restraint and especially the associated treatment affected the neuromotor maturation mainly in male progeny. At adult age, we noticed anxiety, motor deficit and exploratory behavior impairment in male offspring co-exposed to WiFi radiation and restraint, and in female progeny subjected to three treatments. The biochemical investigation showed that, all three treatments produced global oxidative stress in brain of both sexes. As for serum biochemistry, phosphorus, magnesium, glucose, triglycerides and calcium levels were disrupted. Taken together, prenatal WiFi radiation and restraint, alone and combined, provoked several behavioral and biochemical impairments at both juvenile and adult age of the offspring. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Time resolution improvement of Schottky CdTe PET detectors using digital signal processing

    International Nuclear Information System (INIS)

    Nakhostin, M.; Ishii, K.; Kikuchi, Y.; Matsuyama, S.; Yamazaki, H.; Torshabi, A. Esmaili

    2009-01-01

    We present the results of our study on the timing performance of Schottky CdTe PET detectors using the technique of digital signal processing. The coincidence signals between a CdTe detector (15x15x1 mm 3 ) and a fast liquid scintillator detector were digitized by a fast digital oscilloscope and analyzed. In the analysis, digital versions of the elements of timing circuits, including pulse shaper and time discriminator, were created and a digital implementation of the Amplitude and Rise-time Compensation (ARC) mode of timing was performed. Owing to a very fine adjustment of the parameters of timing measurement, a good time resolution of less than 9.9 ns (FWHM) at an energy threshold of 150 keV was achieved. In the next step, a new method of time pickoff for improvement of timing resolution without loss in the detection efficiency of CdTe detectors was examined. In the method, signals from a CdTe detector are grouped by their rise-times and different procedures of time pickoff are applied to the signals of each group. Then, the time pickoffs are synchronized by compensating the fixed time offset, caused by the different time pickoff procedures. This method leads to an improved time resolution of ∼7.2 ns (FWHM) at an energy threshold of as low as 150 keV. The methods presented in this work are computationally fast enough to be used for online processing of data in an actual PET system.

  9. Digital signal processing for CdTe detectors using VXIbus data collection systems

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Daiji; Takahashi, Hiroyuki; Kurahashi, Tomohiko; Iguchi, Tetsuo; Nakazawa, Masaharu

    1996-07-01

    Recently fast signal digitizing technique has been developed, and signal waveforms with very short time periods can be obtained. In this paper, we analyzed each measured pulse which was digitized by an apparatus of this kind, and tried to improve an energy resolution of a CdTe semiconductor detector. The result of the energy resolution for {sup 137}Cs 662 keV photopeak was 13 keV. Also, we developed a fast data collection system based on VXIbus standard, and the counting rate on this system was obtained about 50 counts per second. (author)

  10. Realization of guitar audio effects using methods of digital signal processing

    Science.gov (United States)

    Buś, Szymon; Jedrzejewski, Konrad

    2015-09-01

    The paper is devoted to studies on possibilities of realization of guitar audio effects by means of methods of digital signal processing. As a result of research, some selected audio effects corresponding to the specifics of guitar sound were realized as the real-time system called Digital Guitar Multi-effect. Before implementation in the system, the selected effects were investigated using the dedicated application with a graphical user interface created in Matlab environment. In the second stage, the real-time system based on a microcontroller and an audio codec was designed and realized. The system is designed to perform audio effects on the output signal of an electric guitar.

  11. A new approach of digital signal processing in gamma- and X-ray spectroscopy

    CERN Document Server

    Meyer, D C

    1999-01-01

    A new approach of digital signal processing in gamma- and X-ray spectroscopy which overcomes limitations of state-of-the-art systems is described. The basic technical equipment consists of an energy resolving detector with a preamplifier followed by a fast sampling analog digital converter. The basic idea of the approach is the numerical decomposition of the measured signal into distributions caused by single photon absorption processes using standard pulses. The working principle and potential of the approach is demonstrated by the example of preamplifier pulses with large overlap on time scale.

  12. Automated feature detection and identification in digital point-ordered signals

    Science.gov (United States)

    Oppenlander, Jane E.; Loomis, Kent C.; Brudnoy, David M.; Levy, Arthur J.

    1998-01-01

    A computer-based automated method to detect and identify features in digital point-ordered signals. The method is used for processing of non-destructive test signals, such as eddy current signals obtained from calibration standards. The signals are first automatically processed to remove noise and to determine a baseline. Next, features are detected in the signals using mathematical morphology filters. Finally, verification of the features is made using an expert system of pattern recognition methods and geometric criteria. The method has the advantage that standard features can be, located without prior knowledge of the number or sequence of the features. Further advantages are that standard features can be differentiated from irrelevant signal features such as noise, and detected features are automatically verified by parameters extracted from the signals. The method proceeds fully automatically without initial operator set-up and without subjective operator feature judgement.

  13. Implementation of comprehensive address generator for digital signal processor

    Science.gov (United States)

    Kini, Ramesh M.; David, Sumam S.

    2013-03-01

    The performance of signal-processing algorithms implemented in hardware depends on the efficiency of datapath, memory speed and address computation. Pattern of data access in signal-processing applications is complex and it is desirable to execute the innermost loop of a kernel in a single-clock cycle. This necessitates the generation of typically three addresses per clock: two addresses for data sample/coefficient and one for the storage of processed data. Most of the Reconfigurable Processors, designed for multimedia, focus on mapping the multimedia applications written in a high-level language directly on to the reconfigurable fabric, implying the use of same datapath resources for kernel processing and address generation. This results in inconsistent and non-optimal use of finite datapath resources. Presence of a set of dedicated, efficient Address Generator Units (AGUs) helps in better utilisation of the datapath elements by using them only for kernel operations; and will certainly enhance the performance. This article focuses on the design and application-specific integrated circuit implementation of address generators for complex addressing modes required by multimedia signal-processing kernels. A novel algorithm and hardware for AGU is developed for accessing data and coefficients in a bit-reversed order for fast Fourier transform kernel spanning over log 2 N stages, AGUs for zig-zag-ordered data access for entropy coding after Discrete Cosine Transform (DCT), convolution kernels with stored/streaming data, accessing data for motion estimation using the block-matching technique and other conventional addressing modes. When mapped to hardware, they scale linearly in gate complexity with increase in the size.

  14. Hardware embedded fiber sensor interrogation system using intensive digital signal processing

    OpenAIRE

    Wang, Yujuan; Negri, Lucas H.; Kalinowski, Hypolito J.; Mattos, Daniel S.; Negri, Gabriel H.; Paterno, Aleksander S.

    2014-01-01

    The description of an interrogation system for fiber Bragg grating sensors is reported. The full implementation in hardware of the required signal processing is proposed and made publicly available. The hardware description is implemented in a field programmable gate array (FPGA) development kit and the processing units allow one to control an optoelectronic interrogation system that uses the tunable filter method. Since the signal that drives the used Fabry-Perot filter (FFP) using a digital...

  15. Development of a compact and cost effective multi-input digital signal processing system

    Science.gov (United States)

    Darvish-Molla, Sahar; Chin, Kenrick; Prestwich, William V.; Byun, Soo Hyun

    2018-01-01

    A prototype digital signal processing system (DSP) was developed using a microcontroller interfaced with a 12-bit sampling ADC, which offers a considerably inexpensive solution for processing multiple detectors with high throughput. After digitization of the incoming pulses, in order to maximize the output counting rate, a simple algorithm was employed for pulse height analysis. Moreover, an algorithm aiming at the real-time pulse pile-up deconvolution was implemented. The system was tested using a NaI(Tl) detector in comparison with a traditional analogue and commercial digital systems for a variety of count rates. The performance of the prototype system was consistently superior to the analogue and the commercial digital systems up to the input count rate of 61 kcps while was slightly inferior to the commercial digital system but still superior to the analogue system in the higher input rates. Considering overall cost, size and flexibility, this custom made multi-input digital signal processing system (MMI-DSP) was the best reliable choice for the purpose of the 2D microdosimetric data collection, or for any measurement in which simultaneous multi-data collection is required.

  16. An Undergraduate Course and Laboratory in Digital Signal Processing with Field Programmable Gate Arrays

    Science.gov (United States)

    Meyer-Base, U.; Vera, A.; Meyer-Base, A.; Pattichis, M. S.; Perry, R. J.

    2010-01-01

    In this paper, an innovative educational approach to introducing undergraduates to both digital signal processing (DSP) and field programmable gate array (FPGA)-based design in a one-semester course and laboratory is described. While both DSP and FPGA-based courses are currently present in different curricula, this integrated approach reduces the…

  17. A High Density Low Cost Digital Signal Processing Module for Large Scale Radiation Detectors

    International Nuclear Information System (INIS)

    Tan, Hui; Hennig, Wolfgang; Walby, Mark D.; Breus, Dimitry; Harris, Jackson T.; Grudberg, Peter M.; Warburton, William K.

    2013-06-01

    A 32-channel digital spectrometer PIXIE-32 is being developed for nuclear physics or other radiation detection applications requiring digital signal processing with large number of channels at relatively low cost. A single PIXIE-32 provides spectrometry and waveform acquisition for 32 input signals per module whereas multiple modules can be combined into larger systems. It is based on the PCI Express standard which allows data transfer rates to the host computer of up to 800 MB/s. Each of the 32 channels in a PIXIE-32 module accepts signals directly from a detector preamplifier or photomultiplier. Digitally controlled offsets can be individually adjusted for each channel. Signals are digitized in 12-bit, 50 MHz multi-channel ADCs. Triggering, pile-up inspection and filtering of the data stream are performed in real time, and pulse heights and other event data are calculated on an event-by event basis. The hardware architecture, internal and external triggering features, and the spectrometry and waveform acquisition capability of the PIXIE- 32 as well as its capability to distribute clock and triggers among multiple modules, are presented. (authors)

  18. 75 FR 81491 - Digital Television Signals Pursuant to the Satellite Home Viewer Extension and Reauthorization...

    Science.gov (United States)

    2010-12-28

    ... Television Signals Pursuant to the Satellite Home Viewer Extension and Reauthorization Act of 2004 AGENCY... rules to include measurement procedures for determining the strength of a digital broadcast television... the provisions of the Satellite Television Extension and Localism Act of 2010 (STELA). DATES...

  19. Digital signal processing of cylinder pressure data for combustion diagnostics of HCCI engine

    Science.gov (United States)

    Kumar Maurya, Rakesh; Pal, Dev Datt; Kumar Agarwal, Avinash

    2013-03-01

    Diagnosis of combustion is necessary for the estimation of the combustion quality, and control of combustion timing in advanced combustion concepts like HCCI. Combustion diagnostics is often performed using digital processing of pressure signals measured using piezoelectric sensor installed in the combustion chamber of the engine. Four-step pressure signal processing consisting of (i) absolute pressure correction, (ii) phasing w.r.t. crank angle, (iii) cycle averaging and (iv) smoothening is used to get cylinder pressure data from the engine experiments, which is further analyzed to get information about combustion characteristics. This study focuses on various aspect of signal processing (cycle averaging and smoothing) of in-cylinder pressure signal from a HCCI engine acquired using a piezoelectric pressure sensor. Experimental investigations are conducted on a HCCI combustion engine operating at different engine speed/load/air-fuel ratio conditions. The cylinder pressure history of 3000 consecutive engine cycles is acquired for analysis using piezoelectric pressure sensor. This study determines the optimum number of engine cycles to be acquired for reasonably good pressure signals based on standard deviation of in-cylinder pressure, rate of pressure rise and rate of heat release signals. Different signal smoothening methods (using various digital filters) are also analyzed and their results are compared. This study also presents effect of signal processing methods on pressure, pressure rise rate and rate of heat release curves at different engine operating conditions.

  20. Comparison of digital signal-signal beat interference compensation techniques in direct-detection subcarrier modulation systems.

    Science.gov (United States)

    Li, Zhe; Erkilinc, M Sezer; Galdino, Lidia; Shi, Kai; Thomsen, Benn C; Bayvel, Polina; Killey, Robert I

    2016-12-12

    Single-polarization direct-detection transceivers may offer advantages compared to digital coherent technology for some metro, back-haul, access and inter-data center applications since they offer low-cost and complexity solutions. However, a direct-detection receiver introduces nonlinearity upon photo detection, since it is a square-law device, which results in signal distortion due to signal-signal beat interference (SSBI). Consequently, it is desirable to develop effective and low-cost SSBI compensation techniques to improve the performance of such transceivers. In this paper, we compare the performance of a number of recently proposed digital signal processing-based SSBI compensation schemes, including the use of single- and two-stage linearization filters, an iterative linearization filter and a SSBI estimation and cancellation technique. Their performance is assessed experimentally using a 7 × 25 Gb/s wavelength division multiplexed (WDM) single-sideband 16-QAM Nyquist-subcarrier modulation system operating at a net information spectral density of 2.3 (b/s)/Hz.

  1. Enhancement of the automatic ultrasonic signal processing system using digital technology

    International Nuclear Information System (INIS)

    Koo, In Soo; Park, H. Y.; Suh, Y. S.; Kim, D. Hoon; Huh, S.; Sung, S. H.; Jang, G. S.; Ryoo, S. G.; Choi, J. H.; Kim, Y. H.; Lee, J. C.; Kim, D. Hyun; Park, H. J.; Kim, Y. C.; Lee, J. P.; Park, C. H.; Kim, M. S.

    1999-12-01

    The objective of this study is to develop the automatic ultrasonic signal processing system which can be used in the inspection equipment to assess the integrity of the reactor vessel by enhancing the performance of the ultrasonic signal processing system. Main activities of this study divided into three categories such as the development of the circuits for generating ultrasonic signal and receiving the signal from the inspection equipment, the development of signal processing algorithm and H/W of the data processing system, and the development of the specification for application programs and system S/W for the analysis and evaluation computer. The results of main activities are as follows 1) the design of the ultrasonic detector and the automatic ultrasonic signal processing system by using the investigation of the state-of-the-art technology in the inside and outside of the country. 2) the development of H/W and S/W of the data processing system based on the results. Especially, the H/W of the data processing system, which have both advantages of digital and analog controls through the real-time digital signal processing, was developed using the DSP which can process the digital signal in the real-time, and was developed not only firmware of the data processing system in order for the peripherals but also the test algorithm of specimen for the calibration. The application programs and the system S/W of the analysis/evaluation computer were developed. Developed equipment was verified by the performance test. Based on developed prototype for the automatic ultrasonic signal processing system, the localization of the overall ultrasonic inspection equipment for nuclear industries would be expected through the further studies of the H/W establishment of real applications, developing the S/W specification of the analysis computer. (author)

  2. Single chip system LSI for digital still camera signal processing; Doga taio digital still camera yo shingo shori one chip

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, T.; Okada, S.; Kobayashi, A.; Komura, Y.; Kiyozaki, K. [Sanyo Electric Co. Ltd., Osaka (Japan)

    1998-11-01

    This paper introduces the summary of development of a single chip system LSI for digital still camera (DSC) signal real-time processing, which can deal with animation. In developing the LSI, a DSC was identified as a system device, and the target was set to developing a system LSI capable of processing all of the signals from the DSC. In the real-time signal processing, signal processing of animated images and still images with less shutter waiting time was realized by mounting a dedicated M-JPEC core and by signal-processing contraction and elongation of the JPEG with the hardware at high speed. Writing and reading at higher speeds into and from image buffer memories to reduce the shutter waiting time and higher speed transfer of image data were realized by making a dual path architecture inside the LSI. Other functions performed by the software in the built-in RISC core include recording and replaying of voice, preparation of AVI files to replay the images on home-use TV sets, and a window function for DSC to synthesize still images. 7 refs., 8 figs., 2 tabs.

  3. 37 CFR 258.4 - Royalty fee for secondary transmission of digital signals of broadcast stations by satellite...

    Science.gov (United States)

    2010-07-01

    ... transmission of digital signals of broadcast stations by satellite carriers. 258.4 Section 258.4 Patents... AND PROCEDURES ADJUSTMENT OF ROYALTY FEE FOR SECONDARY TRANSMISSIONS BY SATELLITE CARRIERS § 258.4 Royalty fee for secondary transmission of digital signals of broadcast stations by satellite carriers. (a...

  4. A phase-equalized digital multirate filter for 50 Hz signal processing

    Energy Technology Data Exchange (ETDEWEB)

    Vainio, O. [Tampere University of Technology, Signal Processing Laboratory, Tampere (Finland)

    1997-12-31

    A new multistage digital filter is proposed for 50 Hz line frequency signal processing in zero-crossing detectors and synchronous power systems. The purpose of the filter is to extract the fundamental sinusoidal signal from noise and impulsive disturbances so that the output is accurately in phase with the primary input signal. This is accomplished with a cascade of a median filter, a linear-phase FIR filter, and a phase corrector. A 10 kHz output timing resolution is achieved by up-sampling with a customized interpolation filter. (orig.) 15 refs.

  5. 100-GHz Wireless-Over-Fiber Links With Up to 16-Gb/s QPSK Modulation Using Optical Heterodyne Generation and Digital Coherent Detection

    DEFF Research Database (Denmark)

    Sambaraju, R.; Zibar, Darko; Caballero Jambrina, Antonio

    2010-01-01

    In this letter, a novel technique for direct conversion of an optical baseband quadrature phase-shift keying (QPSK) signal to a millimeter-wave wireless signal and subsequent signal demodulation is reported. Optical heterodyne mixing of the optical baseband QPSK signal with a free-running unmodul...

  6. 16 Gb/s QPSK Wireless-over-Fibre Link in 75-110GHz Band Employing Optical Heterodyne Generation and Coherent Detection

    DEFF Research Database (Denmark)

    Zibar, Darko; Sambaraju, Rakesh; Caballero Jambrina, Antonio

    2010-01-01

    We report on the first demonstration of QPSK based Wireless-over-Fibre link in 75-110GHz band with a record capacity of up to 16Gb/s. Photonic wireless signal generation by heterodyne beating of free-running lasers and baud-rate digital coherent detection are employed....

  7. A 60 GHz Frequency Generator Based on a 20 GHz Oscillator and an Implicit Multiplier

    NARCIS (Netherlands)

    Zong, Z.; Babaie, M.; Staszewski, R.B.

    2016-01-01

    This paper proposes a mm-wave frequency generation technique that improves its phase noise (PN) performance and power efficiency. The main idea is that a fundamental 20 GHz signal and its sufficiently strong third harmonic at 60 GHz are generated simultaneously in a single oscillator. The desired 60

  8. Full-field wrist pulse signal acquisition and analysis by 3D Digital Image Correlation

    Science.gov (United States)

    Xue, Yuan; Su, Yong; Zhang, Chi; Xu, Xiaohai; Gao, Zeren; Wu, Shangquan; Zhang, Qingchuan; Wu, Xiaoping

    2017-11-01

    Pulse diagnosis is an essential part in four basic diagnostic methods (inspection, listening, inquiring and palpation) in traditional Chinese medicine, which depends on longtime training and rich experience, so computerized pulse acquisition has been proposed and studied to ensure the objectivity. To imitate the process that doctors using three fingertips with different pressures to feel fluctuations in certain areas containing three acupoints, we established a five dimensional pulse signal acquisition system adopting a non-contacting optical metrology method, 3D digital image correlation, to record the full-field displacements of skin fluctuations under different pressures. The system realizes real-time full-field vibration mode observation with 10 FPS. The maximum sample frequency is 472 Hz for detailed post-processing. After acquisition, the signals are analyzed according to the amplitude, pressure, and pulse wave velocity. The proposed system provides a novel optical approach for digitalizing pulse diagnosis and massive pulse signal data acquisition for various types of patients.

  9. On-board digital signal processing technologies for present and future SCPC systems

    Science.gov (United States)

    Kato, Shuzo; Ohtani, Kohichi; Kohri, Takehru; Morikura, Masahiro; Umehira, Masahiro

    1988-09-01

    This paper surveys trends in digital and analog ICs and LSICs, including radiation hardness performance. An optimal selection of devices and suitable architectures for SCPC multicarrier demodulators is discussed. The results show good and clear guidelines for device and architecture selection for on-board signal processing at the present time and toward the year 2000. It is shown that, for on-board SCPC multicarrier demodulation, a transmultiplexer type channel divider and digital common demodulator has a good performance with a medium number of channels for regeneration.

  10. A Digital Correlation Spectrometer Chip with 1 GHz Bandwidth, 4096 Spectral Channels, and 4 W Power Consumption for Passive Microwave Remote Sensing Instruments, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The scope of this project is to provide a digital auto-correlation spectrometer fabricated on a single integrated circuit for NASA's future Earth-Sun System missions...

  11. Digital nonlinearity compensation in high-capacity optical communication systems considering signal spectral broadening effect.

    Science.gov (United States)

    Xu, Tianhua; Karanov, Boris; Shevchenko, Nikita A; Lavery, Domaniç; Liga, Gabriele; Killey, Robert I; Bayvel, Polina

    2017-10-11

    Nyquist-spaced transmission and digital signal processing have proved effective in maximising the spectral efficiency and reach of optical communication systems. In these systems, Kerr nonlinearity determines the performance limits, and leads to spectral broadening of the signals propagating in the fibre. Although digital nonlinearity compensation was validated to be promising for mitigating Kerr nonlinearities, the impact of spectral broadening on nonlinearity compensation has never been quantified. In this paper, the performance of multi-channel digital back-propagation (MC-DBP) for compensating fibre nonlinearities in Nyquist-spaced optical communication systems is investigated, when the effect of signal spectral broadening is considered. It is found that accounting for the spectral broadening effect is crucial for achieving the best performance of DBP in both single-channel and multi-channel communication systems, independent of modulation formats used. For multi-channel systems, the degradation of DBP performance due to neglecting the spectral broadening effect in the compensation is more significant for outer channels. Our work also quantified the minimum bandwidths of optical receivers and signal processing devices to ensure the optimal compensation of deterministic nonlinear distortions.

  12. Influence of Wilbraham-Gibbs Phenomenon on Digital Stochastic Measurement of EEG Signal Over an Interval

    Directory of Open Access Journals (Sweden)

    Sovilj P.

    2014-10-01

    Full Text Available Measurement methods, based on the approach named Digital Stochastic Measurement, have been introduced, and several prototype and small-series commercial instruments have been developed based on these methods. These methods have been mostly investigated for various types of stationary signals, but also for non-stationary signals. This paper presents, analyzes and discusses digital stochastic measurement of electroencephalography (EEG signal in the time domain, emphasizing the problem of influence of the Wilbraham-Gibbs phenomenon. The increase of measurement error, related to the Wilbraham-Gibbs phenomenon, is found. If the EEG signal is measured and measurement interval is 20 ms wide, the average maximal error relative to the range of input signal is 16.84 %. If the measurement interval is extended to 2s, the average maximal error relative to the range of input signal is significantly lowered - down to 1.37 %. Absolute errors are compared with the error limit recommended by Organisation Internationale de Métrologie Légale (OIML and with the quantization steps of the advanced EEG instruments with 24-bit A/D conversion

  13. A comparative study of chaotic and white noise signals in digital watermarking

    International Nuclear Information System (INIS)

    Mooney, Aidan; Keating, John G.; Pitas, Ioannis

    2008-01-01

    Digital watermarking is an ever increasing and important discipline, especially in the modern electronically-driven world. Watermarking aims to embed a piece of information into digital documents which their owner can use to prove that the document is theirs, at a later stage. In this paper, performance analysis of watermarking schemes is performed on white noise sequences and chaotic sequences for the purpose of watermark generation. Pseudorandom sequences are compared with chaotic sequences generated from the chaotic skew tent map. In particular, analysis is performed on highpass signals generated from both these watermark generation schemes, along with analysis on lowpass watermarks and white noise watermarks. This analysis focuses on the watermarked images after they have been subjected to common image distortion attacks. It is shown that signals generated from highpass chaotic signals have superior performance than highpass noise signals, in the presence of such attacks. It is also shown that watermarks generated from lowpass chaotic signals have superior performance over the other signal types analysed

  14. Preserving privacy of online digital physiological signals using blind and reversible steganography.

    Science.gov (United States)

    Shiu, Hung-Jr; Lin, Bor-Sing; Huang, Chien-Hung; Chiang, Pei-Ying; Lei, Chin-Laung

    2017-11-01

    Physiological signals such as electrocardiograms (ECG) and electromyograms (EMG) are widely used to diagnose diseases. Presently, the Internet offers numerous cloud storage services which enable digital physiological signals to be uploaded for convenient access and use. Numerous online databases of medical signals have been built. The data in them must be processed in a manner that preserves patients' confidentiality. A reversible error-correcting-coding strategy will be adopted to transform digital physiological signals into a new bit-stream that uses a matrix in which is embedded the Hamming code to pass secret messages or private information. The shared keys are the matrix and the version of the Hamming code. An online open database, the MIT-BIH arrhythmia database, was used to test the proposed algorithms. The time-complexity, capacity and robustness are evaluated. Comparisons of several evaluations subject to related work are also proposed. This work proposes a reversible, low-payload steganographic scheme for preserving the privacy of physiological signals. An (n,  m)-hamming code is used to insert (n - m) secret bits into n bits of a cover signal. The number of embedded bits per modification is higher than in comparable methods, and the computational power is efficient and the scheme is secure. Unlike other Hamming-code based schemes, the proposed scheme is both reversible and blind. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. 2.1 GHz electromagnetic field does not change contractility and intracellular Ca2+ transients but decreases β-adrenergic responsiveness through nitric oxide signaling in rat ventricular myocytes.

    Science.gov (United States)

    Olgar, Yusuf; Hidisoglu, Enis; Celen, Murat Cenk; Yamasan, Bilge Eren; Yargicoglu, Piraye; Ozdemir, Semir

    2015-01-01

    Due to the increasing use of wireless technology in developing countries, particularly mobile phones, the influence of electromagnetic fields (EMF) on biologic systems has become the subject of an intense debate. Therefore, in this study we investigated the effect of 2.1 GHz EMF on contractility and beta-adrenergic (β-AR) responsiveness of ventricular myocytes. Rats were randomized to the following groups: Sham rats (SHAM) and rats exposed to 2.1 GHz EMF for 2 h/day for 10 weeks (EM-10). Sarcomere shortening and Ca(2+) transients were recorded in isolated myocytes loaded with Fura2-AM and electrically stimulated at 1 Hz, while L-type Ca(2+) currents (I(CaL)) were measured using whole-cell patch clamping at 36 ± 1°C. Cardiac nitric oxide (NO) levels were measured in tissue samples using a colorimetric assay kit. Fractional shortening and amplitude of the matched Ca(2+) transients were not changed in EM-10 rats. Although the isoproterenol-induced (10(-6) M) I(CaL) response was reduced in rats exposed to EMF, basal I(CaL) density in myocytes was similar between the two groups (p < 0.01). Moreover, EMF exposure led to a significant increase in nitric oxide levels in rat heart (p < 0.02). Long-term exposure to 2.1 GHz EMF decreases β-AR responsiveness of ventricular myocytes through NO signaling.

  16. An InGaAs/InP 40 GHz CML static frequency divider

    International Nuclear Information System (INIS)

    Su Yongbo; Jin Zhi; Cheng Wei; Ge Ji; Wang Xiantai; Chen Gaopeng; Liu Xinyu; Xu Anhuai; Qi Ming

    2011-01-01

    Static frequency dividers are widely used as a circuit performance benchmark or figure-of-merit indicator to gauge a particular device technology's ability to implement high speed digital and integrated high performance mixed-signal circuits. We report a 2 : 1 static frequency divider in InGaAs/InP heterojunction bipolar transistor technology. This is the first InP based digital integrated circuit ever reported on the mainland of China. The divider is implemented in differential current mode logic (CML) with 30 transistors. The circuit operated at a peak clock frequency of 40 GHz and dissipated 650 mW from a single -5 V supply. (semiconductor integrated circuits)

  17. Digital broadcasting

    International Nuclear Information System (INIS)

    Park, Ji Hyeong

    1999-06-01

    This book contains twelve chapters, which deals with digitization of broadcast signal such as digital open, digitization of video signal and sound signal digitization of broadcasting equipment like DTPP and digital VTR, digitization of equipment to transmit such as digital STL, digital FPU and digital SNG, digitization of transmit about digital TV transmit and radio transmit, digital broadcasting system on necessity and advantage, digital broadcasting system abroad and Korea, digital broadcasting of outline, advantage of digital TV, ripple effect of digital broadcasting and consideration of digital broadcasting, ground wave digital broadcasting of DVB-T in Europe DTV in U.S.A and ISDB-T in Japan, HDTV broadcasting, satellite broadcasting, digital TV broadcasting in Korea, digital radio broadcasting and new broadcasting service.

  18. Operation and performance of a longitudinal feedback system using digital signal processing

    International Nuclear Information System (INIS)

    Teytelman, D.; Fox, J.; Hindi, H.

    1994-01-01

    A programmable longitudinal feedback system using a parallel array of AT ampersand T 1610 digital signal processors has been developed as a component of the PEP-II R ampersand D program. This system has been installed at the Advanced Light Source (LBL) and implements full speed bunch by bunch signal processing for storage rings with bunch spacing of 4ns. Open and closed loop results showing the action of the feedback system are presented, and the system is shown to damp coupled-bunch instabilities in the ALS. A unified PC-based software environment for the feedback system operation is also described

  19. Data-derived symbol synchronization of MASK and QASK signals. [for multilevel digital communication systems

    Science.gov (United States)

    Simon, M. K.

    1974-01-01

    Multilevel amplitude-shift-keying (MASK) and quadrature amplitude-shift-keying (QASK) as signaling techniques for multilevel digital communications systems, and the problem of providing symbol synchronization in the receivers of such systems are discussed. A technique is presented for extracting symbol sync from an MASK or QASK signal. The scheme is a generalization of the data transition tracking loop used in PSK systems. The performance of the loop was analyzed in terms of its mean-squared jitter and its effects on the data detection process in MASK and QASK systems.

  20. Quantum secure direct communication of digital and analog signals using continuum coherent states

    Science.gov (United States)

    Guerra, Antônio Geovan de Araújo Holanda; Rios, Francisco Franklin Sousa; Ramos, Rubens Viana

    2016-11-01

    In this work, we present optical schemes for secure direct quantum communication of digital and analog signals using continuum coherent states and frequency-dependent phase modulation. The main advantages of the proposed schemes are that they do not use entangled states and they can be implemented with today technology. The theory of quantum interference of continuum coherent state is described, and the optical setups for secure direct communication are presented and their securities are discussed.

  1. Depth of quantization in signals of the digital X-ray television

    International Nuclear Information System (INIS)

    Beuthan, J.

    1989-01-01

    The technological realization of image acquisition and processing in digital X-ray television in methodical dependence on the image-forming purpose places particular requirements in signal quantization. By evaluation of experimental results with simultaneous modification of a special calculation method an optimum quantization stage is ascertained with method-relevant quantization characteristic. In addition to consideration made so far in this field a self-contained solution is presented with inclusion of vision physiology and information gain. (author)

  2. Universal Michelson Gires-Tournois interferometer optical interleaver based on digital signal processing.

    Science.gov (United States)

    Zhang, Juan; Yang, Xiaowei

    2010-03-01

    Optical interleavers based on Michelson Gires-Tournois interferometer (MGTI) with arbitrary cascaded reflectors for symmetrical or asymmetrical periodic frequency response with arbitrary duty cycles are defined as universal MGTI optical interleaver (UMGTIOI). It can significantly enhance flexibility and applicability of optical networks. A novel and simple method based on digital signal processing is proposed for the design of UMGTIOI. Different kinds of design examples are given to confirm effectiveness of the method.

  3. Measurement of definite integral of sinusoidal signal absolute value third power using digital stochastic method

    Directory of Open Access Journals (Sweden)

    Beljić Željko

    2017-01-01

    Full Text Available In this paper a special case of digital stochastic measurement of the third power of definite integral of sinusoidal signal’s absolute value, using 2-bit AD converters is presented. This case of digital stochastic method had emerged from the need to measure power and energy of the wind. Power and energy are proportional to the third power of wind speed. Anemometer output signal is sinusoidal. Therefore an integral of the third power of sinusoidal signal is zero. Two approaches are proposed for the third power calculation of the wind speed signal. One approach is to use absolute value of sinusoidal signal (before AD conversion for which there is no need of multiplier hardware change. The second approach requires small multiplier hardware change, but input signal remains unchanged. For the second approach proposed minimal hardware change was made to calculate absolute value of the result after AD conversion. Simulations have confirmed theoretical analysis. Expected precision of wind energy measurement of proposed device is better than 0,00051% of full scale. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR32019

  4. Application of adaptive digital signal processing to speech enhancement for the hearing impaired.

    Science.gov (United States)

    Chabries, D M; Christiansen, R W; Brey, R H; Robinette, M S; Harris, R W

    1987-01-01

    A major complaint of individuals with normal hearing and hearing impairments is a reduced ability to understand speech in a noisy environment. This paper describes the concept of adaptive noise cancelling for removing noise from corrupted speech signals. Application of adaptive digital signal processing has long been known and is described from a historical as well as technical perspective. The Widrow-Hoff LMS (least mean square) algorithm developed in 1959 forms the introduction to modern adaptive signal processing. This method uses a "primary" input which consists of the desired speech signal corrupted with noise and a second "reference" signal which is used to estimate the primary noise signal. By subtracting the adaptively filtered estimate of the noise, the desired speech signal is obtained. Recent developments in the field as they relate to noise cancellation are described. These developments include more computationally efficient algorithms as well as algorithms that exhibit improved learning performance. A second method for removing noise from speech, for use when no independent reference for the noise exists, is referred to as single channel noise suppression. Both adaptive and spectral subtraction techniques have been applied to this problem--often with the result of decreased speech intelligibility. Current techniques applied to this problem are described, including signal processing techniques that offer promise in the noise suppression application.

  5. Digitally generated excitation and near-baseband quadrature detection of rapid scan EPR signals.

    Science.gov (United States)

    Tseitlin, Mark; Yu, Zhelin; Quine, Richard W; Rinard, George A; Eaton, Sandra S; Eaton, Gareth R

    2014-12-01

    The use of multiple synchronized outputs from an arbitrary waveform generator (AWG) provides the opportunity to perform EPR experiments differently than by conventional EPR. We report a method for reconstructing the quadrature EPR spectrum from periodic signals that are generated with sinusoidal magnetic field modulation such as continuous wave (CW), multiharmonic, or rapid scan experiments. The signal is down-converted to an intermediate frequency (IF) that is less than the field scan or field modulation frequency and then digitized in a single channel. This method permits use of a high-pass analog filter before digitization to remove the strong non-EPR signal at the IF, that might otherwise overwhelm the digitizer. The IF is the difference between two synchronized X-band outputs from a Tektronix AWG 70002A, one of which is for excitation and the other is the reference for down-conversion. To permit signal averaging, timing was selected to give an exact integer number of full cycles for each frequency. In the experiments reported here the IF was 5kHz and the scan frequency was 40kHz. To produce sinusoidal rapid scans with a scan frequency eight times IF, a third synchronized output generated a square wave that was converted to a sine wave. The timing of the data acquisition with a Bruker SpecJet II was synchronized by an external clock signal from the AWG. The baseband quadrature signal in the frequency domain was reconstructed. This approach has the advantages that (i) the non-EPR response at the carrier frequency is eliminated, (ii) both real and imaginary EPR signals are reconstructed from a single physical channel to produce an ideal quadrature signal, and (iii) signal bandwidth does not increase relative to baseband detection. Spectra were obtained by deconvolution of the reconstructed signals for solid BDPA (1,3-bisdiphenylene-2-phenylallyl) in air, 0.2mM trityl OX63 in water, 15 N perdeuterated tempone, and a nitroxide with a 0.5G partially-resolved proton

  6. The digital traces of bubbles: feedback cycles between socio-economic signals in the Bitcoin economy.

    Science.gov (United States)

    Garcia, David; Tessone, Claudio J; Mavrodiev, Pavlin; Perony, Nicolas

    2014-10-06

    What is the role of social interactions in the creation of price bubbles? Answering this question requires obtaining collective behavioural traces generated by the activity of a large number of actors. Digital currencies offer a unique possibility to measure socio-economic signals from such digital traces. Here, we focus on Bitcoin, the most popular cryptocurrency. Bitcoin has experienced periods of rapid increase in exchange rates (price) followed by sharp decline; we hypothesize that these fluctuations are largely driven by the interplay between different social phenomena. We thus quantify four socio-economic signals about Bitcoin from large datasets: price on online exchanges, volume of word-of-mouth communication in online social media, volume of information search and user base growth. By using vector autoregression, we identify two positive feedback loops that lead to price bubbles in the absence of exogenous stimuli: one driven by word of mouth, and the other by new Bitcoin adopters. We also observe that spikes in information search, presumably linked to external events, precede drastic price declines. Understanding the interplay between the socio-economic signals we measured can lead to applications beyond cryptocurrencies to other phenomena that leave digital footprints, such as online social network usage. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  7. A fast continuous magnetic field measurement system based on digital signal processors

    International Nuclear Information System (INIS)

    Velev, G.V.; Carcagno, R.; DiMarco, J.; Kotelnikov, S.; Lamm, M.; Makulski, A.; Maroussov, V.; Nehring, R.; Nogiec, J.; Orris, D.; Poukhov, O.; Prakoshyn, F.; Schlabach, P.; Tompkins, J.C.

    2005-01-01

    In order to study dynamic effects in accelerator magnets, such as the decay of the magnetic field during the dwell at injection and the rapid so-called ''snapback'' during the first few seconds of the resumption of the energy ramp, a fast continuous harmonics measurement system was required. A new magnetic field measurement system, based on the use of digital signal processors (DSP) and Analog to Digital (A/D) converters, was developed and prototyped at Fermilab. This system uses Pentek 6102 16 bit A/D converters and the Pentek 4288 DSP board with the SHARC ADSP-2106 family digital signal processor. It was designed to acquire multiple channels of data with a wide dynamic range of input signals, which are typically generated by a rotating coil probe. Data acquisition is performed under a RTOS, whereas processing and visualization are performed under a host computer. Firmware code was developed for the DSP to perform fast continuous readout of the A/D FIFO memory and integration over specified intervals, synchronized to the probe's rotation in the magnetic field. C, C++ and Java code was written to control the data acquisition devices and to process a continuous stream of data. The paper summarizes the characteristics of the system and presents the results of initial tests and measurements

  8. The digital traces of bubbles: feedback cycles between socio-economic signals in the Bitcoin economy

    Science.gov (United States)

    Garcia, David; Tessone, Claudio J.; Mavrodiev, Pavlin; Perony, Nicolas

    2014-01-01

    What is the role of social interactions in the creation of price bubbles? Answering this question requires obtaining collective behavioural traces generated by the activity of a large number of actors. Digital currencies offer a unique possibility to measure socio-economic signals from such digital traces. Here, we focus on Bitcoin, the most popular cryptocurrency. Bitcoin has experienced periods of rapid increase in exchange rates (price) followed by sharp decline; we hypothesize that these fluctuations are largely driven by the interplay between different social phenomena. We thus quantify four socio-economic signals about Bitcoin from large datasets: price on online exchanges, volume of word-of-mouth communication in online social media, volume of information search and user base growth. By using vector autoregression, we identify two positive feedback loops that lead to price bubbles in the absence of exogenous stimuli: one driven by word of mouth, and the other by new Bitcoin adopters. We also observe that spikes in information search, presumably linked to external events, precede drastic price declines. Understanding the interplay between the socio-economic signals we measured can lead to applications beyond cryptocurrencies to other phenomena that leave digital footprints, such as online social network usage. PMID:25100315

  9. A 12GHz 210fs 6mW digital PLL with sub-sampling binary phase detector and voltage-time modulated DCO

    NARCIS (Netherlands)

    Ru, Z.; Geraedts, P.F.J.; Klumperink, Eric A.M.; He, X.; Nauta, Bram

    2013-01-01

    An integer-N digital PLL architecture is presented that simplifies the critical phase path using a sub-sampling binary (bang-bang) phase detector. Two power-efficient techniques are presented that can reduce DCO frequency tuning step by voltage-domain and time-domain (pulse-width) modulating the DCO

  10. Photonic filtering of microwave signals in the frequency range of 0.01-20 GHz using a Fabry-Perot filter

    International Nuclear Information System (INIS)

    Aguayo-Rodriguez, G; Zaldivar-Huerta, I E; GarcIa-Juarez, A; Rodriguez-Asomoza, J; Larger, L; Courjal, N

    2011-01-01

    We demonstrate experimentally the efficiency of tuning of a photonic filter in the frequency range of 0.01 to 20 GHz. The presented work combines the use of a multimode optical source associated with a dispersive optical fiber to obtain the filtering effect. Tunability effect is achieved by the use of a Fabry-Perot filter that allows altering the spectral characteristics of the optical source. Experimental results are validated by means of numerical simulations. The scheme here proposed has a potential application in the field of optical telecommunications.

  11. Digital signal processing by virtual instrumentation of a MEMS magnetic field sensor for biomedical applications.

    Science.gov (United States)

    Juárez-Aguirre, Raúl; Domínguez-Nicolás, Saúl M; Manjarrez, Elías; Tapia, Jesús A; Figueras, Eduard; Vázquez-Leal, Héctor; Aguilera-Cortés, Luz A; Herrera-May, Agustín L

    2013-11-05

    We present a signal processing system with virtual instrumentation of a MEMS sensor to detect magnetic flux density for biomedical applications. This system consists of a magnetic field sensor, electronic components implemented on a printed circuit board (PCB), a data acquisition (DAQ) card, and a virtual instrument. It allows the development of a semi-portable prototype with the capacity to filter small electromagnetic interference signals through digital signal processing. The virtual instrument includes an algorithm to implement different configurations of infinite impulse response (IIR) filters. The PCB contains a precision instrumentation amplifier, a demodulator, a low-pass filter (LPF) and a buffer with operational amplifier. The proposed prototype is used for real-time non-invasive monitoring of magnetic flux density in the thoracic cage of rats. The response of the rat respiratory magnetogram displays a similar behavior as the rat electromyogram (EMG).

  12. Low-Latency Digital Signal Processing for Feedback and Feedforward in Quantum Computing and Communication

    Science.gov (United States)

    Salathé, Yves; Kurpiers, Philipp; Karg, Thomas; Lang, Christian; Andersen, Christian Kraglund; Akin, Abdulkadir; Krinner, Sebastian; Eichler, Christopher; Wallraff, Andreas

    2018-03-01

    Quantum computing architectures rely on classical electronics for control and readout. Employing classical electronics in a feedback loop with the quantum system allows us to stabilize states, correct errors, and realize specific feedforward-based quantum computing and communication schemes such as deterministic quantum teleportation. These feedback and feedforward operations are required to be fast compared to the coherence time of the quantum system to minimize the probability of errors. We present a field-programmable-gate-array-based digital signal processing system capable of real-time quadrature demodulation, a determination of the qubit state, and a generation of state-dependent feedback trigger signals. The feedback trigger is generated with a latency of 110 ns with respect to the timing of the analog input signal. We characterize the performance of the system for an active qubit initialization protocol based on the dispersive readout of a superconducting qubit and discuss potential applications in feedback and feedforward algorithms.

  13. Detection of coherent beam-beam modes with digitized beam position monitor signals

    CERN Document Server

    Stancari, G.; White, S.M.

    2014-01-01

    A system for bunch-by-bunch detection of transverse proton and antiproton coherent oscillations in the Fermilab Tevatron collider is described. It is based on the signal from a single beam-position monitor located in a region of the ring with large amplitude functions. The signal is digitized over a large number of turns and Fourier-analyzed offline with a dedicated algorithm. To enhance the signal, band-limited noise is applied to the beam for about 1 s. This excitation does not adversely affect the circulating beams even at high luminosities. The device has a response time of a few seconds, a frequency resolution of $1.6\\times 10^{-5}$ in fractional tune, and it is sensitive to oscillation amplitudes of 60 nm. It complements Schottky detectors as a diagnostic tool for tunes, tune spreads, and beam-beam effects. Measurements of coherent mode spectra are presented and compared with models of beam-beam oscillations.

  14. Digital Signal Processing by Virtual Instrumentation of a MEMS Magnetic Field Sensor for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Héctor Vázquez-Leal

    2013-11-01

    Full Text Available We present a signal processing system with virtual instrumentation of a MEMS sensor to detect magnetic flux density for biomedical applications. This system consists of a magnetic field sensor, electronic components implemented on a printed circuit board (PCB, a data acquisition (DAQ card, and a virtual instrument. It allows the development of a semi-portable prototype with the capacity to filter small electromagnetic interference signals through digital signal processing. The virtual instrument includes an algorithm to implement different configurations of infinite impulse response (IIR filters. The PCB contains a precision instrumentation amplifier, a demodulator, a low-pass filter (LPF and a buffer with operational amplifier. The proposed prototype is used for real-time non-invasive monitoring of magnetic flux density in the thoracic cage of rats. The response of the rat respiratory magnetogram displays a similar behavior as the rat electromyogram (EMG.

  15. Fabrication of an electro-absorption transceiver with a monolithically integrated optical amplifier for fiber transmission of 40–60 GHz radio signals

    International Nuclear Information System (INIS)

    Zhang, Andy Zhenzhong; Wang, Qin; Fonjallaz, Pierre-Yves; Almqvist, Susanne; Karlsson, Stefan; Kjebon, Olle; Schatz, Richard; Chacinski, Marek; Thylén, Lars; Berggren, Jesper; Hammar, Mattias; Honecker, Jörg; Steffan, Andreas

    2011-01-01

    We report on the fabrication of a monolithically integrated semiconductor optical amplifier (SOA) and a reflective electro-absorption transceiver (EAT) for 40–60 GHz radio-over-fiber applications. The EAT can either function as a transmitter (reflective modulator) or as a receiver (photodetector) depending on operation mode. The SOA and the EAT sections are based on different InGaAsP multiple quantum-well active layers connected by a butt joint. Benzocyclobutene is used to reduce the capacitance beside the ridge mesa. Devices are designed to have a peaked response at the operating frequency through the design of microwave waveguides on top of the devices. The packaged device exhibits at 0.1 mW optical input power an amplified DC responsivity of 18.5 mA mW −1 and a modulation efficiency of 0.67 mW V −1 . The estimated radio frequency loss at 40 GHz of an optical link consisting of two SOA–EAT devices was 23 dB using an unmodulated optical input carrier to the transmitter of 0.94 mW

  16. Tandem demodulation lock-in amplifier based on digital signal processor for dual-modulated spectroscopy.

    Science.gov (United States)

    Qin, Jianhuan; Huang, Zhiming; Ge, Yujian; Hou, Yun; Chu, Junhao

    2009-03-01

    Dual-modulated spectroscopy is one of the most powerful methods in the measurement of modulation spectroscopy. Here we develop a tandem lock-in amplifier (LIA) based on digital signal processor to implement a novel algorithm of tandem demodulation. The theoretical analysis of demodulation algorithm is presented, and the implementation of this tandem LIA is described in detail. Compared to the traditional demodulating way with two LIAs in cascade, this tandem LIA eliminates the extra quantization error of redundant analog-to-digital and digital-to-analog conversions and removes the limitation to the time constant in the commercial LIA, hence lowers the requirement of frequency ratio in dual-modulated spectroscopy. The applications are given as examples in the photoreflectance (PR) measurements of GaAs (100) thin film and GaSb bulk material, respectively, at the different optical energy regions. The experimental results indicate that this tandem is well capable of PR spectra measurement with good PR lineshapes and reasonable signal noise ratio. A brief comparison of GaAs PR results between tandem LIA and two LIAs is made to prove the efficiency and advantages of the tandem LIA.

  17. 25 Gbit/s QPSK Hybrid Fiber-Wireless Transmission in the W-Band (75–110 GHz) With Remote Antenna Unit for In-Building Wireless Networks

    DEFF Research Database (Denmark)

    Pang, Xiaodan; Caballero Jambrina, Antonio; Dogadaev, Anton Konstantinovich

    2012-01-01

    -band radio-over-fiber (RoF) signal is generated and distributed to the remote antenna unit (RAU). One laser carries 12.5 Gbaud optical baseband QPSK data, and the other acts as a carrier frequency generating laser. The two signals are heterodyne mixed at a photodetector in the RAU, and the baseband QPSK...... signal is transparently up-converted to the W-band. After the wireless transmission, the received signal is first down-converted to an intermediate frequency (IF) at 13.5 GHz at an electrical balanced mixer before being sampled and converted to the digital domain. A digital-signal-processing (DSP...

  18. Linear and Nonlinear Impairment Compensation in Coherent Optical Transmission with Digital Signal Processing

    DEFF Research Database (Denmark)

    Porto da Silva, Edson

    Digital signal processing (DSP) has become one of the main enabling technologies for the physical layer of coherent optical communication networks. The DSP subsystems are used to implement several functionalities in the digital domain, from synchronization to channel equalization. Flexibility...... and effectiveness of DSP contribute to reducing costs and increase reliability of optical communications systems. The work presented in this thesis focuses on DSP subsystems for coherent optical communication systems. In particular, the contributions presented in this thesis relate to the following topics: (I) Kerr...... are performed to evaluate the proposed methods. In conclusion, the results presented in this thesis contribute to the state-of-the-art of DSP for coherent optical communication over single-mode fibers (SMFs). The techniques investigated have the potential to improve performance and reliability of such systems...

  19. Digital broadband linearization of optical links.

    Science.gov (United States)

    Lam, Daniel; Fard, Ali M; Buckley, Brandon; Jalali, Bahram

    2013-02-15

    We present a digital postprocessing linearization technique to efficiently suppress dynamic distortions added to a wideband signal in an analog optical link. Our technique achieves up to 35 dB suppression of intermodulation distortions over multiple octaves of signal bandwidth. In contrast to conventional linearization methods, it does not require excessive analog bandwidth for performing digital correction. This is made possible by regenerating undesired distortions from the captured output, and subtracting it from the distorted digitized signal. Moreover, we experimentally demonstrate a record spurious-free dynamic range of 120 dB·Hz(2/3) over a 6 GHz electrical signal bandwidth. While our digital broadband linearization technique advances state-of-the-art optical links, it can also be applied to other nonlinear dynamic systems.

  20. The Solar Probe Plus Radio Frequency Spectrometer: Measurement requirements, analog design, and digital signal processing

    Science.gov (United States)

    Pulupa, M.; Bale, S. D.; Bonnell, J. W.; Bowen, T. A.; Carruth, N.; Goetz, K.; Gordon, D.; Harvey, P. R.; Maksimovic, M.; Martínez-Oliveros, J. C.; Moncuquet, M.; Saint-Hilaire, P.; Seitz, D.; Sundkvist, D.

    2017-03-01

    The Radio Frequency Spectrometer (RFS) is a two-channel digital receiver and spectrometer, which will make remote sensing observations of radio waves and in situ measurements of electrostatic and electromagnetic fluctuations in the solar wind. A part of the FIELDS suite for Solar Probe Plus (SPP), the RFS is optimized for measurements in the inner heliosphere, where solar radio bursts are more intense and the plasma frequency is higher compared to previous measurements at distances of 1 AU or greater. The inputs to the RFS receiver are the four electric antennas mounted near the front of the SPP spacecraft and a single axis of the SPP search coil magnetometer (SCM). Each RFS channel selects a monopole or dipole antenna input, or the SCM input, via multiplexers. The primary data products from the RFS are autospectra and cross spectra from the selected inputs. The spectra are calculated using a polyphase filter bank, which enables the measurement of low amplitude signals of interest in the presence of high-amplitude narrowband noise generated by spacecraft systems. We discuss the science signals of interest driving the RFS measurement objectives, describe the RFS analog design and digital signal processing, and show examples of current performance.

  1. AUTOMATIC RECOGNITION OF BOTH INTER AND INTRA CLASSES OF DIGITAL MODULATED SIGNALS USING ARTIFICIAL NEURAL NETWORK

    Directory of Open Access Journals (Sweden)

    JIDE JULIUS POPOOLA

    2014-04-01

    Full Text Available In radio communication systems, signal modulation format recognition is a significant characteristic used in radio signal monitoring and identification. Over the past few decades, modulation formats have become increasingly complex, which has led to the problem of how to accurately and promptly recognize a modulation format. In addressing these challenges, the development of automatic modulation recognition systems that can classify a radio signal’s modulation format has received worldwide attention. Decision-theoretic methods and pattern recognition solutions are the two typical automatic modulation recognition approaches. While decision-theoretic approaches use probabilistic or likelihood functions, pattern recognition uses feature-based methods. This study applies the pattern recognition approach based on statistical parameters, using an artificial neural network to classify five different digital modulation formats. The paper deals with automatic recognition of both inter-and intra-classes of digitally modulated signals in contrast to most of the existing algorithms in literature that deal with either inter-class or intra-class modulation format recognition. The results of this study show that accurate and prompt modulation recognition is possible beyond the lower bound of 5 dB commonly acclaimed in literature. The other significant contribution of this paper is the usage of the Python programming language which reduces computational complexity that characterizes other automatic modulation recognition classifiers developed using the conventional MATLAB neural network toolbox.

  2. Digital passband processing of wideband-modulated optical signals for enhanced underwater imaging.

    Science.gov (United States)

    Mullen, Linda; Lee, Robert; Nash, Justin

    2016-11-01

    Radar modulation, demodulation, and signal processing techniques have been merged with laser imaging to enhance visibility in murky underwater environments. The modulation provides a way to reject multiple scattered light that would otherwise reduce image contrast and resolution. Recent work has focused on the use of wideband modulation schemes and digital passband processing to resolve range details of an underwater scene. Use of the CLEAN algorithm has also been investigated to extract object features that are obscured by scattered light. Results from controlled laboratory experiments show an improvement in the range resolution and accuracy of underwater imagery relative to data collected with a conventional short pulse system.

  3. POSITION CONTROL OF BRUSHLESS DC MOTOR BASED ON DIGITAL SIGNAL PROCESSING

    Directory of Open Access Journals (Sweden)

    Çetin GENÇER

    2006-01-01

    Full Text Available Brushless DC Motors (BLDC have been used widely high performance control systems which are depended on to development of power electronic and control technology. In these motors to fed commutated supply, the control of position without oscilation has been required. In this study, position control of BLDC with digital signal processing has been implemented by a proportional-derivative (PD controller because of its simple structure. It has been seen that the controller which is proposed from simulation and experimental studies, has a quick dynamic responce with nonoscillation.

  4. Electro-magnetic analysis of high-frequency digital signal processors.

    Science.gov (United States)

    Li, Bing; Lei, Mingzhu; Chen, Meiyuan; Zhang, Lanyong

    2016-01-01

    High-frequency digital signal processors are increasingly suffering from electro-magnetic interference, due to its ever-increasing integration level and operation speed. The accurate prediction of its electro-magnetic effects require less effort to be spared in the design procedures to obtain better electro-magnetic compatibility and to avoid later modifications that are lengthy and expensive. In this paper, the dipole method is implemented to predict the magnetic impacts of DSP6713 system in order to reduce its design costs.

  5. The effects of advanced digital signal processing concepts on VLSIC/VHSIC design

    Science.gov (United States)

    Jankowski, C.

    Implementations of sophisticated mathematical techniques in advanced digital signal processors can significantly improve performance. Future VLSI and VHSI circuit designs must include the practical realization of these algorithms. A structured design approach is described and illustrated with examples from a RNS FIR filter processor development project. The CAE hardware and software required to support tasks of this complexity are also discussed. An EWS is recommended for controlling essential functions such as logic optimization, simulation and verification. The total IC design system is illustrated with the implementation of a new high performance algorithm for computing complex magnitude.

  6. Optimal space communications techniques. [using digital and phase locked systems for signal processing

    Science.gov (United States)

    Schilling, D. L.

    1974-01-01

    Digital multiplication of two waveforms using delta modulation (DM) is discussed. It is shown that while conventional multiplication of two N bit words requires N2 complexity, multiplication using DM requires complexity which increases linearly with N. Bounds on the signal-to-quantization noise ratio (SNR) resulting from this multiplication are determined and compared with the SNR obtained using standard multiplication techniques. The phase locked loop (PLL) system, consisting of a phase detector, voltage controlled oscillator, and a linear loop filter, is discussed in terms of its design and system advantages. Areas requiring further research are identified.

  7. Improvement of the energy resolution via an optimized digital signal processing in GERDA Phase I

    International Nuclear Information System (INIS)

    Agostini, M.; Bode, T.; Budjas, D.; Janicsko Csathy, J.; Lazzaro, A.; Schoenert, S.; Allardt, M.; Domula, A.; Lehnert, B.; Schneider, B.; Wester, T.; Wilsenach, H.; Zuber, K.; Bakalyarov, A.M.; Belyaev, S.T.; Lebedev, V.I.; Zhukov, S.V.; Balata, M.; D'Andrea, V.; Di Vacri, A.; Junker, M.; Laubenstein, M.; Macolino, C.; Zavarise, P.; Barabanov, I.; Bezrukov, L.; Doroshkevich, E.; Fedorova, O.; Gurentsov, V.; Kazalov, V.; Kuzminov, V.V.; Lubsandorzhiev, B.; Moseev, P.; Selivanenko, O.; Veresnikova, A.; Yanovich, E.; Barros, N.; Baudis, L.; Benato, G.; Walter, M.; Bauer, C.; Heisel, M.; Heusser, G.; Hofmann, W.; Kihm, T.; Kirsch, A.; Knoepfle, K.T.; Lindner, M.; Maneschg, W.; Salathe, M.; Schreiner, J.; Schwingenheuer, B.; Simgen, H.; Smolnikov, A.; Stepaniuk, M.; Wagner, V.; Wegmann, A.; Becerici-Schmidt, N.; Caldwell, A.; Liao, H.Y.; Majorovits, B.; Palioselitis, D.; Schulz, O.; Vanhoefer, L.; Bellotti, E.; Belogurov, S.; Kornoukhov, V.N.; Bettini, A.; Brugnera, R.; Garfagnini, A.; Hemmer, S.; Medinaceli, E.; Sada, C.; Sturm, K. von; Borowicz, D.; Brudanin, V.; Egorov, V.; Kochetov, O.; Nemchenok, I.; Rumyantseva, N.; Zhitnikov, I.; Zinatulina, D.; Cattadori, C.; Chernogorov, A.; Demidova, E.V.; Kirpichnikov, I.V.; Vasenko, A.A.; Falkenstein, R.; Freund, K.; Grabmayr, P.; Hegai, A.; Jochum, J.; Schmitt, C.; Schuetz, A.K.; Frodyma, N.; Misiaszek, M.; Panas, K.; Pelczar, K.; Wojcik, M.; Zuzel, G.; Gangapshev, A.; Gusev, K.; Hult, M.; Lutter, G.; Inzhechik, L.V.; Klimenko, A.; Lippi, I.; Stanco, L.; Ur, C.A.; Lubashevskiy, A.; Pandola, L.; Pullia, A.; Riboldi, S.; Shirchenko, M.

    2015-01-01

    An optimized digital shaping filter has been developed for the Gerda experiment which searches for neutrinoless double beta decay in 76 Ge. The GERDA Phase I energy calibration data have been reprocessed and an average improvement of 0.3 keV in energy resolution (FWHM) corresponding to 10% at the Q value for 0νββ decay in 76 Ge is obtained. This is possible thanks to the enhanced low-frequency noise rejection of this Zero Area Cusp (ZAC) signal shaping filter. (orig.)

  8. Detection of interference phase by digital computation of quadrature signals in homodyne laser interferometry

    Czech Academy of Sciences Publication Activity Database

    Řeřucha, Šimon; Buchta, Zdeněk; Šarbort, Martin; Lazar, Josef; Číp, Ondřej

    2012-01-01

    Roč. 12, č. 10 (2012), s. 14095-14112 ISSN 1424-8220 R&D Projects: GA ČR GAP102/10/1813; GA MŠk ED0017/01/01; GA MPO FR-TI2/705; GA MPO FR-TI1/241; GA MŠk EE2.3.30.0054 Institutional support: RVO:68081731 Keywords : digital signal processing * homodyne detection * laser interferometry * optical metrology Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.953, year: 2012

  9. Experimental verification of preset time count rate meters based on adaptive digital signal processing algorithms

    Directory of Open Access Journals (Sweden)

    Žigić Aleksandar D.

    2005-01-01

    Full Text Available Experimental verifications of two optimized adaptive digital signal processing algorithms implemented in two pre set time count rate meters were per formed ac cording to appropriate standards. The random pulse generator realized using a personal computer, was used as an artificial radiation source for preliminary system tests and performance evaluations of the pro posed algorithms. Then measurement results for background radiation levels were obtained. Finally, measurements with a natural radiation source radioisotope 90Sr-90Y, were carried out. Measurement results, con ducted without and with radio isotopes for the specified errors of 10% and 5% showed to agree well with theoretical predictions.

  10. Seismic qualification using digital signal processing/modal testing and finite element techniques

    International Nuclear Information System (INIS)

    Steedman, J.B.; Edelstein, A.

    1983-01-01

    A systematic procedure in which digital signal processing, modal testing and finite element techniques can be used to seismically qualify Class IE equipment for use in nuclear generating stations is presented. A new method was also developed in which measured transmissibility functions and Fourier transformation techniques were combined to compute instrument response spectra. As an illustrative example of the qualification method, the paper follows the qualification of a safety related Class IE Heating, Ventilating, and Air Conditioning (HVAC) Control Panel subjected to both seismic and hydrodynamic loading conditions

  11. Measuring system for magnetic field and temperature with digital signal processing

    Directory of Open Access Journals (Sweden)

    Druzhinin A. A.

    2013-10-01

    Full Text Available The measuring system for the magnetic field and temperature using silicon whiskers p-type conductivity as a primary device has been developed. The developed system allows the measurement of the magnetic field and temperature in the temperature range 4,2—77 K, as well as to measure the temperature under the influence of magnetic fields in the range of 100—300 K. It is shown that this system is suitable for the conversion of small signals using a programmable gain amplifier and analog-to-digital converter with high resolution.

  12. ROC analyses of the signal detection on CRT-displayed radiographs after digitalization

    International Nuclear Information System (INIS)

    Yamashita, Kazuya; Inamoto, Kazuo; Morikawa, Kaoru

    1986-01-01

    In the present paper, we have described experimental evaluation studies using the ROC analysis on displayed images of the radiographs converted after digitization. Two types of images were used in these studies : one was signal images composed of 2 mm diameter beads disseminated (absorbed images) and another was 2 mm diameter cavities (penetrated images). The psychophysical experiment was carried out using the rating experiment of obtaining the ROC curve based on the signal detection theory. The detectability was evaluated by the maximum transmitted information. The results were summarized as follows: (1) The detectabilities of the images on the CRT were significantly lower than those of the original ones. The decreasing rate of information was 67.8 % in the bead signal images and 65.6 % in the cavity signal images. (2) However, the detectability of the cavity signal images was two times better than that of the bead. (3) Detectabilities could be improved to 98.9 % by double gradient processing and 70.1 % by quadruple gradient processing in the studies of the bead images. (author)

  13. Cryogenic 160-GHz MMIC Heterodyne Receiver Module

    Science.gov (United States)

    Samoska, Lorene A.; Soria, Mary M.; Owen, Heather R.; Dawson, Douglas E.; Kangaslahti, Pekka P.; Gaier, Todd C.; Voll, Patricia; Lau, Judy; Sieth, Matt; Church, Sarah

    2011-01-01

    A cryogenic 160-GHz MMIC heterodyne receiver module has demonstrated a system noise temperature of 100 K or less at 166 GHz. This module builds upon work previously described in Development of a 150-GHz MMIC Module Prototype for Large-Scale CMB Radiation (NPO-47664), NASA Tech Briefs, Vol. 35, No. 8 (August 2011), p. 27. In the original module, the local oscillator signal was saturating the MMIC low-noise amplifiers (LNAs) with power. In order to suppress the local oscillator signal from reaching the MMIC LNAs, the W-band (75 110 GHz) signal had to be filtered out before reaching 140 170 GHz. A bandpass filter was developed to cover 120 170 GHz, using microstrip parallel-coupled lines to achieve the desired filter bandwidth, and ensure that the unwanted W-band local oscillator signal would be sufficiently suppressed. With the new bandpass filter, the entire receiver can work over the 140 180-GHz band, with a minimum system noise temperature of 460 K at 166 GHz. The module was tested cryogenically at 20 K ambient temperature, and it was found that the receiver had a noise temperature of 100 K over an 8-GHz bandwidth. The receiver module now includes a microstrip bandpass filter, which was designed to have a 3-dB bandwidth of approximately 120-170 GHz. The filter was fabricated on a 3-mil-thick alumina substrate. The filter design was based on a W-band filter design made at JPL and used in the QUIET (Q/U Imaging ExperimenT) radiometer modules. The W-band filter was scaled for a new center frequency of 150 GHz, and the microstrip segments were changed accordingly. Also, to decrease the bandwidth of the resulting scaled design, the center gaps between the microstrip lines were increased (by four micrometers in length) compared to the gaps near the edges. The use of the 150-GHz bandpass filter has enabled the receiver module to function well at room temperature. The system noise temperature was measured to be less than 600 K (at room temperature) from 154 to 168 GHz

  14. Design Navigation Computer System Based on Double Digital Signal Process and FPGA

    Directory of Open Access Journals (Sweden)

    Jie Yan

    2013-03-01

    Full Text Available The article describes the design and implementation of integrated navigation embedded computer system based on double DSP and FPGA. In the system, TMS320C6727 (C6727 and TMS320C6713 (C6713 digital signal processor (DSP, which produced by TI are used as the core processing chip. C6727 is responsibility to de-noising the inertial measurement unit (IMU original signal, and send the IMU data to C6713. C6713 is responsibility to collect the IMU and GNSS data, run navigation algorithm and send the navigation information to other implements. The I/0 interface, timing control, data buffering and address bus decoding modes are implemented in FPGA. This design can improve the system real-time performance and reliability.

  15. Digital Signal Processing and Generation for a DC Current Transformer for Particle Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Zorzetti, Silvia [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2013-01-01

    The thesis topic, digital signal processing and generation for a DC current transformer, focuses on the most fundamental beam diagnostics in the field of particle accelerators, the measurement of the beam intensity, or beam current. The technology of a DC current transformer (DCCT) is well known, and used in many areas, including particle accelerator beam instrumentation, as non-invasive (shunt-free) method to monitor the DC current in a conducting wire, or in our case, the current of charged particles travelling inside an evacuated metal pipe. So far, custom and commercial DCCTs are entirely based on analog technologies and signal processing, which makes them inflexible, sensitive to component aging, and difficult to maintain and calibrate.

  16. Real time implementation of a linear predictive coding algorithm on digital signal processor DSP32C

    International Nuclear Information System (INIS)

    Sheikh, N.M.; Usman, S.R.; Fatima, S.

    2002-01-01

    Pulse Code Modulation (PCM) has been widely used in speech coding. However, due to its high bit rate. PCM has severe limitations in application where high spectral efficiency is desired, for example, in mobile communication, CD quality broadcasting system etc. These limitation have motivated research in bit rate reduction techniques. Linear predictive coding (LPC) is one of the most powerful complex techniques for bit rate reduction. With the introduction of powerful digital signal processors (DSP) it is possible to implement the complex LPC algorithm in real time. In this paper we present a real time implementation of the LPC algorithm on AT and T's DSP32C at a sampling frequency of 8192 HZ. Application of the LPC algorithm on two speech signals is discussed. Using this implementation , a bit rate reduction of 1:3 is achieved for better than tool quality speech, while a reduction of 1.16 is possible for speech quality required in military applications. (author)

  17. Digital signal processing and spectral analysis for scientists concepts and applications

    CERN Document Server

    Alessio, Silvia Maria

    2016-01-01

    This book covers the basics of processing and spectral analysis of monovariate discrete-time signals. The approach is practical, the aim being to acquaint the reader with the indications for and drawbacks of the various methods and to highlight possible misuses. The book is rich in original ideas, visualized in new and illuminating ways, and is structured so that parts can be skipped without loss of continuity. Many examples are included, based on synthetic data and real measurements from the fields of physics, biology, medicine, macroeconomics etc., and a complete set of MATLAB exercises requiring no previous experience of programming is provided. Prior advanced mathematical skills are not needed in order to understand the contents: a good command of basic mathematical analysis is sufficient. Where more advanced mathematical tools are necessary, they are included in an Appendix and presented in an easy-to-follow way. With this book, digital signal processing leaves the domain of engineering to address the ne...

  18. Noise and signal detection in digital x-ray detectors using the spatial definition of SNR

    Science.gov (United States)

    Kyprianou, Iacovos S.; Badano, Aldo; Park, Subok; Liu, Haimo; Myers, Kyle J.

    2009-02-01

    For task specific evaluation of imaging systems it is necessary to obtain detailed descriptions of their noise and deterministic properties. In the past we have developed an experimental and theoretical methodology to estimate the deterministic detector response of a digital x-ray imaging system, also known as the H matrix. In this paper we have developed the experimental methodology for the evaluation of the quantum and electronic noise of digital radiographic detectors using the covariance matrix K. Using the H matrix we calculated the transfer of a simulated coronary artery constriction through an imaging system's detector, and with the covariance matrix we calculated the detectability (or Signal-to-Noise Ratio) and the detection probability. The eigenvalues and eigenvectors of the covariance matrix were presented and the electronic and quantum noise were analyzed. We found that the exposure at which the electronic noise equals the quantum noise at 90 kVp was 0.2 μR. We compared the ideal Hotelling observer with the Fourier definition of the SNR for a toroidal stenosis on a cylindrical vessel. Because of the shift-invariance and cyclo-stationarity assumptions, the Fourier SNR overestimates the performance of imaging systems. This methodology can be used for task specific evaluation and optimization of a digital x-ray imaging system.

  19. A digital wireless system for closed-loop inhibition of nociceptive signals

    Science.gov (United States)

    Zuo, Chao; Yang, Xiaofei; Wang, Yang; Hagains, Christopher E.; Li, Ai-Ling; Peng, Yuan B.; Chiao, J.-C.

    2012-10-01

    Neurostimulation of the spinal cord or brain has been used to inhibit nociceptive signals in pain management applications. Nevertheless, most of the current neurostimulation models are based on open-loop system designs. There is a lack of closed-loop systems for neurostimulation in research with small freely-moving animals and in future clinical applications. Based on our previously developed analog wireless system for closed-loop neurostimulation, a digital wireless system with real-time feedback between recorder and stimulator modules has been developed to achieve multi-channel communication. The wireless system includes a wearable recording module, a wearable stimulation module and a transceiver connected to a computer for real-time and off-line data processing, display and storage. To validate our system, wide dynamic range neurons in the spinal cord dorsal horn have been recorded from anesthetized rats in response to graded mechanical stimuli (brush, pressure and pinch) applied in the hind paw. The identified nociceptive signals were used to automatically trigger electrical stimulation at the periaqueductal gray in real time to inhibit their own activities by the closed-loop design. Our digital wireless closed-loop system has provided a simplified and efficient method for further study of pain processing in freely-moving animals and potential clinical application in patients. Groups 1, 2 and 3 contributed equally to this project.

  20. Combination of digital signal processing methods towards an improved analysis algorithm for structural health monitoring.

    Science.gov (United States)

    Pentaris, Fragkiskos P.; Makris, John P.

    2013-04-01

    In Structural Health Monitoring (SHM) is of great importance to reveal valuable information from the recorded SHM data that could be used to predict or indicate structural fault or damage in a building. In this work a combination of digital signal processing methods, namely FFT along with Wavelet Transform is applied, together with a proposed algorithm to study frequency dispersion, in order to depict non-linear characteristics of SHM data collected in two university buildings under natural or anthropogenic excitation. The selected buildings are of great importance from civil protection point of view, as there are the premises of a public higher education institute, undergoing high use, stress, visit from academic staff and students. The SHM data are collected from two neighboring buildings that have different age (4 and 18 years old respectively). Proposed digital signal processing methods are applied to the data, presenting a comparison of the structural behavior of both buildings in response to seismic activity, weather conditions and man-made activity. Acknowledgments This work was supported in part by the Archimedes III Program of the Ministry of Education of Greece, through the Operational Program "Educational and Lifelong Learning", in the framework of the project entitled «Interdisciplinary Multi-Scale Research of Earthquake Physics and Seismotectonics at the front of the Hellenic Arc (IMPACT-ARC) » and is co-financed by the European Union (European Social Fund) and Greek National Fund.

  1. Joint digital signal processing of Nyquist-wavelength division multiplexing superchannel with group detection

    Science.gov (United States)

    Zhang, Tianyun; Yao, Shuchang; Fu, Songnian; Tang, Ming; Liu, Deming

    2014-12-01

    To relax the limited sampling rate of an analog-to-digital converter (ADC) and to reduce the complexity of conventional fiber-optical superchannel coherent detection, we propose and demonstrate a joint digital signal processing (DSP) technique of Nyquist-wavelength division multiplexing superchannel with group detection. At the receiver side, three Nyquist-spaced channels with 12.5 Gbaud polarization multiplexing-quadrature phase shift keying signals are group detected with a sampling rate per channel of 1.33 times over the normal sampling rate. A modified carrier separation technique is then put forward to retrieve the high-frequency interference component of both the designated channel and its adjacent channels, which can subsequently be used to recover the designated channel with new constant modulus algorithm-based joint multiinput-multioutput equalizers. The results show that the proposed group detection and joint DSP algorithm can simultaneously improve the transmission performance and reduce the complexity of both the transmitter and receiver, regardless of bandwidth restrictions from the waveshaper, ADC module, and coherent receiver.

  2. A SystemC-Based Design Methodology for Digital Signal Processing Systems

    Directory of Open Access Journals (Sweden)

    Christian Haubelt

    2007-03-01

    Full Text Available Digital signal processing algorithms are of big importance in many embedded systems. Due to complexity reasons and due to the restrictions imposed on the implementations, new design methodologies are needed. In this paper, we present a SystemC-based solution supporting automatic design space exploration, automatic performance evaluation, as well as automatic system generation for mixed hardware/software solutions mapped onto FPGA-based platforms. Our proposed hardware/software codesign approach is based on a SystemC-based library called SysteMoC that permits the expression of different models of computation well known in the domain of digital signal processing. It combines the advantages of executability and analyzability of many important models of computation that can be expressed in SysteMoC. We will use the example of an MPEG-4 decoder throughout this paper to introduce our novel methodology. Results from a five-dimensional design space exploration and from automatically mapping parts of the MPEG-4 decoder onto a Xilinx FPGA platform will demonstrate the effectiveness of our approach.

  3. The IceCube data acquisition system: Signal capture, digitization,and timestamping

    Energy Technology Data Exchange (ETDEWEB)

    The IceCube Collaboration; Matis, Howard

    2009-03-02

    IceCube is a km-scale neutrino observatory under construction at the South Pole with sensors both in the deep ice (InIce) and on the surface (IceTop). The sensors, called Digital Optical Modules (DOMs), detect, digitize and timestamp the signals from optical Cherenkov-radiation photons. The DOM Main Board (MB) data acquisition subsystem is connected to the central DAQ in the IceCube Laboratory (ICL) by a single twisted copper wire-pair and transmits packetized data on demand. Time calibration ismaintained throughout the array by regular transmission to the DOMs of precisely timed analog signals, synchronized to a central GPS-disciplined clock. The design goals and consequent features, functional capabilities, and initial performance of the DOM MB, and the operation of a combined array of DOMs as a system, are described here. Experience with the first InIce strings and the IceTop stations indicates that the system design and performance goals have been achieved.

  4. Optical phase-modulated radio-over-fiber links with k-means algorithm for digital demodulation of 8PSK subcarrier multiplexed signals

    DEFF Research Database (Denmark)

    Guerrero Gonzalez, Neil; Zibar, Darko; Yu, Xianbin

    2010-01-01

    A k-means algorithm for phase recovery of three, 50 Mbaud, 8PSK subcarrier multiplexed signals at 5 GHz for optical phase-modulated radio-over-fiber is proposed and experimentally demonstrated after 40 km of single mode fiber transmission......A k-means algorithm for phase recovery of three, 50 Mbaud, 8PSK subcarrier multiplexed signals at 5 GHz for optical phase-modulated radio-over-fiber is proposed and experimentally demonstrated after 40 km of single mode fiber transmission...

  5. Experimental Demonstration of Nonlinearity and Phase Noise Tolerant 16-QAM OFDM W-Band (75–110 GHz) Signal Over Fiber System

    DEFF Research Database (Denmark)

    Deng, Lei; Pang, Xiaodan; Tafur Monroy, Idelfonso

    2014-01-01

    We propose a nonlinearity and phase noise tolerant orthogonal frequency division multiplexing (OFDM) W-band signal over fiber system based on phase modulation and photonic heterodyne up-conversion techniques. By heterodyne mixing the phase-modulated optical OFDM signal with a free-running laser...... in the photodiode, the constant envelope OFDM W-band wireless signal is obtained to suppress the nonlinear impairments. Moreover, the phase noises of the beating lasers appear as additive terms to the desired signal, and could be easily filtered out without complex phase noise estimation and compensation algorithms....... In our experiment, 4 Gb/s QPSK and 8 Gb/s 16-QAM constant envelope OFDM W-band signals are transmitted over 22.8 km single mode fiber and 2.3 m air distance with achieved bit-error-rate performance below the forward error correction limit....

  6. Effect of Delayed Digital Hypothermia on Lamellar Inflammatory Signaling in the Oligofructose Laminitis Model.

    Science.gov (United States)

    Dern, K; Watts, M; Werle, B; van Eps, A; Pollitt, C; Belknap, J

    2017-03-01

    In the oligofructose (OF) model of sepsis-related laminitis (SRL), digital hypothermia ("cryotherapy") initiated before the onset of clinical signs is reported not only to limit lamellar injury, but also to cause marked inhibition of lamellar inflammatory signaling. Because hypothermia also has been reported to be protective when not initiated until the onset of lameness in the OF model of SRL, we hypothesized that the lamellar protection conferred by hypothermia is caused by local lamellar inhibition of inflammatory signaling as described when hypothermia was initiated earlier in the disease process. Eight Standardbred geldings aged 3-11 years with no lameness and no abnormalities of the feet detectable by gross or radiographic examination. Using the OF model of SRL, lamellar mRNA concentrations of proinflammatory cytokines, chemokines, and endothelial adhesion proteins were compared between samples from treated limbs (CRYO, submerged in ice water for 36 hour starting at the onset of lameness), untreated limbs (NON-CRYO, opposite limb from CRYO limbs maintained at ambient temperature), and untreated limbs from normal horses in which laminitis was not induced (CON). Although OF administration resulted in increases in lamellar mRNA concentrations of several inflammatory mediators in NON-CRYO limbs (vs CON), digital hypothermia had no significant effect on these increases. The lack of inflammatory inhibition in lamellar tissue samples in our study indicates that the protective effects of digital hypothermia instituted at the onset of clinical signs of laminitis do not arise from inhibition of inflammatory pathways. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  7. Neutron-Gamma Pulse Shape Discrimination With Ne-213 Liquid Scintillator By Using Digital Signal Processing Combined With Similarity Method

    International Nuclear Information System (INIS)

    Mardiyanto

    2008-01-01

    Neutron-Gamma Pulse Shape Discrimination with a NE-213 Liquid Scintillator by Using Digital Signal Processing Combined with Similarity Method. Measurement of mixed neutron-gamma radiation is difficult because a nuclear detector is usually sensitive to both radiations. A new attempt of neutron-gamma pulse shape discrimination for a NE-213 liquid scintillator is presented by using digital signal processing combined with an off-line similarity method. The output pulse shapes are digitized with a high speed digital oscilloscope. The n-γ discrimination is done by calculating the index of each pulse shape, which is determined by the similarity method, and then fusing it with its corresponding pulse height. Preliminary results demonstrate good separation of neutron and gamma-ray signals from a NE-213 scintillator with a simple digital system. The results were better than those with a conventional rise time method. Figure of Merit is used to determine the quality of discrimination. The figure of merit of the discrimination using digital signal processing combined with off-line similarity method are 1.9; 1.7; 1.1; 1.1; and 0.8; on the other hand by using conventional method the rise time are 0.9; 0.9; 0.9; 0.7; and 0.4 for the equivalent electron energy of 800; 278; 139; 69; and 30 keV. (author)

  8. Comparison of Performance of Transcranial Contralateral Routing of Signal, Pre-Implanted Trimmer Digital and Digital Bone Anchored Hearing Aid in Adults with Unilateral Hearing Loss.

    Science.gov (United States)

    Devi, Neelamegarajan; Chatni, Suma; Ramadevi, Kasetty Jagannathaiah S; Fakruddin, Darga Baba

    2015-06-11

    Individuals with unilateral hearing loss of severe-profound degree face listening difficulties while localizing a sound source and while perceiving speech in the presence of noise. The objective was to compare the efficacy of the digitally programmable bone anchored hearing aid (BAHA), trimmer digital BAHA and the transcranial contralateral routing of signal (T-CROS) in improving the listening performance in adults with unilateral hearing loss. Twenty-four adults with unilateral hearing loss was assessed for sound field thresholds, speech perception performance in quiet and noise (direct and indirect conditions) and the subjective quality rating of speech in unaided and aided with either T-CROS or digitally programmable BAHA or trimmer digital BAHA attached to the headband. Results indicated that the participants performed better with both the digitally programmable and the trimmer digital BAHA than the T-CROS in both quiet and noise. However, the digitally programmable BAHA performed better when the speech arrived from the poorer ear side. The current study helps in prioritizing the hearing amplification devices for the trial and also helps in arriving at the appropriate hearing amplification device for the individuals with unilateral hearing loss.

  9. Comparison of performance of transcranial contralateral routing of signal, pre-implanted trimmer digital and digital bone anchored hearing aid in adults with unilateral hearing loss

    Directory of Open Access Journals (Sweden)

    Neelamegarajan Devi

    2015-06-01

    Full Text Available Individuals with unilateral hearing loss of severe-profound degree face listening difficulties while localizing a sound source and while perceiving speech in the presence of noise. The objective was to compare the efficacy of the digitally programmable bone anchored hearing aid (BAHA, trimmer digital BAHA and the transcranial contralateral routing of signal (T-CROS in improving the listening performance in adults with unilateral hearing loss. Twenty-four adults with unilateral hearing loss was assessed for sound field thresholds, speech perception performance in quiet and noise (direct and indirect conditions and the subjective quality rating of speech in unaided and aided with either T-CROS or digitally programmable BAHA or trimmer digital BAHA attached to the headband. Results indicated that the participants performed better with both the digitally programmable and the trimmer digital BAHA than the T-CROS in both quiet and noise. However, the digitally programmable BAHA performed better when the speech arrived from the poorer ear side. The current study helps in prioritizing the hearing amplification devices for the trial and also helps in arriving at the appropriate hearing amplification device for the individuals with unilateral hearing loss.

  10. A 205GHz Amplifier in 90nm CMOS Technology

    Science.gov (United States)

    2017-03-01

    disadvantages at the higher frequency range with the worst case scenario happening when the device operates near its fmax. This is chiefly due to...measured S-parameters of the fabricated 205GHz amplifier. C1     in out 14.17-17.50 GHz Signal Generator   Amplifier/ Multiplier   0.9 V

  11. An optimized image analysis algorithm for detecting nuclear signals in digital whole slides for histopathology.

    Science.gov (United States)

    Paulik, Róbert; Micsik, Tamás; Kiszler, Gábor; Kaszál, Péter; Székely, János; Paulik, Norbert; Várhalmi, Eszter; Prémusz, Viktória; Krenács, Tibor; Molnár, Béla

    2017-06-01

    Nuclear estrogen receptor (ER), progesterone receptor (PR) and Ki-67 protein positive tumor cell fractions are semiquantitatively assessed in breast cancer for prognostic and predictive purposes. These biomarkers are usually revealed using immunoperoxidase methods resulting in diverse signal intensity and frequent inhomogeneity in tumor cell nuclei, which are routinely scored and interpreted by a pathologist during conventional light-microscopic examination. In the last decade digital pathology-based whole slide scanning and image analysis algorithms have shown tremendous development to support pathologists in this diagnostic process, which can directly influence patient selection for targeted- and chemotherapy. We have developed an image analysis algorithm optimized for whole slide quantification of nuclear immunostaining signals of ER, PR, and Ki-67 proteins in breast cancers. In this study, we tested the consistency and reliability of this system both in a series of brightfield and DAPI stained fluorescent samples. Our method allows the separation of overlapping cells and signals, reliable detection of vesicular nuclei and background compensation, especially in FISH stained slides. Detection accuracy and the processing speeds were validated in routinely immunostained breast cancer samples of varying reaction intensities and image qualities. Our technique supported automated nuclear signal detection with excellent efficacy: Precision Rate/Positive Predictive Value was 90.23 ± 4.29%, while Recall Rate/Sensitivity was 88.23 ± 4.84%. These factors and average counting speed of our algorithm were compared with two other open source applications (QuPath and CellProfiler) and resulted in 6-7% higher Recall Rate, while 4- to 30-fold higher processing speed. In conclusion, our image analysis algorithm can reliably detect and count nuclear signals in digital whole slides or any selected large areas i.e. hot spots, thus can support pathologists in assessing

  12. Fractal Communication System Using Digital Signal Processing Starter Kit (DSK TMS320c6713

    Directory of Open Access Journals (Sweden)

    Arsyad Ramadhan Darlis

    2015-12-01

    Full Text Available In 1992, Wornell and Oppenheim did research on a modulation which is formed by using wavelet theory. In some other studies, proved that this modulation can survive on a few channels and has reliability in some applications. Because of this modulation using the concept of fractal, then it is called as fractalmodulation. Fractal modulation is formed by inserting information signal into fractal signals that are selffractal similary. This modulation technique has the potential to replace the OFDM (Orthogonal Frequency Division Multiplexing, which is currently used on some of the latest telecommunication technologies. The purpose of this research is to implement the fractal communication system using Digital Signal Processing Starter Kit (DSK TMS320C6713 without using AWGN and Rayleigh channel in order to obtain the ideal performance of the system. From the simulation results using MATLAB7.4. it appears that this communication system has good performance on some channels than any other communication systems. While in terms of implementation by using (DSK via TMS320C6713 Code Composer Studio (CCS, it can be concluded that thefractal communication system has a better execution time on some tests.

  13. Use of higher order signal moments and high speed digital sampling technique for neutron flux measurements

    Science.gov (United States)

    Baers, L. B.; Gutierrez, T. Rivero; Mendoza, R. A. Carrillo; Santana, G. Jimenez

    1993-08-01

    The second (conventional variance or Campbell signal), the third, and the modified fourth order central signal moments associated with the amplified and filtered currents from two electrodes of an ex-core neutron sensitive fission detector were measured versus the reactor power of the 1-MW TRIGA reactor in Mexico City. Two channels of a high-speed (400-MHz) multiplexing data sampler and an analog-to-digital converter with 12-b resolution and 1-Mword buffer memory were used. The data were further retrieved into a PC, and estimates for autocorrelation and cross-correlation moments up to the fifth order, coherence, skewness, excess, etc., quantities were calculated offline. Five-mode operation of the detector was achieved, including conventional counting rates and currents in agreement with theory and the authors' previous results with analog techniques. The signals are proportional to the neutron flux and reactor power in some flux ranges. The suppression of background noise is improved and the lower limit of the measurement range is extended as the order of moment is increased, in agreement with theory.

  14. An all digital phase locked loop for synchronization of a sinusoidal signal embedded in white Gaussian noise

    Science.gov (United States)

    Reddy, C. P.; Gupta, S. C.

    1973-01-01

    An all digital phase locked loop which tracks the phase of the incoming sinusoidal signal once per carrier cycle is proposed. The different elements and their functions and the phase lock operation are explained in detail. The nonlinear difference equations which govern the operation of the digital loop when the incoming signal is embedded in white Gaussian noise are derived, and a suitable model is specified. The performance of the digital loop is considered for the synchronization of a sinusoidal signal. For this, the noise term is suitably modelled which allows specification of the output probabilities for the two level quantizer in the loop at any given phase error. The loop filter considered increases the probability of proper phase correction. The phase error states in modulo two-pi forms a finite state Markov chain which enables the calculation of steady state probabilities, RMS phase error, transient response and mean time for cycle skipping.

  15. Digital CODEC for real-time processing of broadcast quality video signals at 1.8 bits/pixel

    Science.gov (United States)

    Shalkhauser, Mary JO; Whyte, Wayne A.

    1991-01-01

    Advances in very large scale integration and recent work in the field of bandwidth efficient digital modulation techniques have combined to make digital video processing technically feasible an potentially cost competitive for broadcast quality television transmission. A hardware implementation was developed for DPCM (differential pulse code midulation)-based digital television bandwidth compression algorithm which processes standard NTSC composite color television signals and produces broadcast quality video in real time at an average of 1.8 bits/pixel. The data compression algorithm and the hardware implementation of the codec are described, and performance results are provided.

  16. Digital signal processing reveals circadian baseline oscillation in majority of mammalian genes.

    Directory of Open Access Journals (Sweden)

    Andrey A Ptitsyn

    2007-06-01

    Full Text Available In mammals, circadian periodicity has been described for gene expression in the hypothalamus and multiple peripheral tissues. It is accepted that 10%-15% of all genes oscillate in a daily rhythm, regulated by an intrinsic molecular clock. Statistical analyses of periodicity are limited by the small size of datasets and high levels of stochastic noise. Here, we propose a new approach applying digital signal processing algorithms separately to each group of genes oscillating in the same phase. Combined with the statistical tests for periodicity, this method identifies circadian baseline oscillation in almost 100% of all expressed genes. Consequently, circadian oscillation in gene expression should be evaluated in any study related to biological pathways. Changes in gene expression caused by mutations or regulation of environmental factors (such as photic stimuli or feeding should be considered in the context of changes in the amplitude and phase of genetic oscillations.

  17. [Digital signal processing of a novel neuron discharge model stimulation strategy for cochlear implants].

    Science.gov (United States)

    Yang, Yiwei; Xu, Yuejin; Miu, Jichang; Zhou, Linghong; Xiao, Zhongju

    2012-10-01

    To apply the classic leakage integrate-and-fire models, based on the mechanism of the generation of physiological auditory stimulation, in the information processing coding of cochlear implants to improve the auditory result. The results of algorithm simulation in digital signal processor (DSP) were imported into Matlab for a comparative analysis. Compared with CIS coding, the algorithm of membrane potential integrate-and-fire (MPIF) allowed more natural pulse discharge in a pseudo-random manner to better fit the physiological structures. The MPIF algorithm can effectively solve the problem of the dynamic structure of the delivered auditory information sequence issued in the auditory center and allowed integration of the stimulating pulses and time coding to ensure the coherence and relevance of the stimulating pulse time.

  18. Families of atomic functions ch a, n ( x) and fup n ( x) in digital signal processing

    Science.gov (United States)

    Kravchenko, V. F.; Konovalov, Ya. Yu.; Pustovoit, V. I.

    2015-05-01

    A new class of weight functions constructed on the basis of family of atomic functions and ch a, n ( x) and fup n ( x) is proposed and substantiated. The study consists of three parts. In the first part, the definition of atomic functions and their convolutions are presented. In the second part, a definition of a new family of atomic functions ch a, n ( x) as convolutions of h a ( x) is given. In the third part, a family of weight functions is constructed by truncation of ch a, n ( x) to the effective support. If smoothening with classical windows is applied after the truncation combined weight functions will be received. The physical characteristics of the weight functions constructed by the direct truncation and in combination with the Hamming and Riesz windows are presented. The found functions can find wide application in problems of digital signal processing, restoration of images, radar, radiometry, radio astronomy, remote probing, and other physical domains.

  19. Low-complexity camera digital signal imaging for video document projection system

    Science.gov (United States)

    Hsia, Shih-Chang; Tsai, Po-Shien

    2011-04-01

    We present high-performance and low-complexity algorithms for real-time camera imaging applications. The main functions of the proposed camera digital signal processing (DSP) involve color interpolation, white balance, adaptive binary processing, auto gain control, and edge and color enhancement for video projection systems. A series of simulations demonstrate that the proposed method can achieve good image quality while keeping computation cost and memory requirements low. On the basis of the proposed algorithms, the cost-effective hardware core is developed using Verilog HDL. The prototype chip has been verified with one low-cost programmable device. The real-time camera system can achieve 1270 × 792 resolution with the combination of extra components and can demonstrate each DSP function.

  20. Virtual instrumentation technique used in the nuclear digital signal processing system design: Energy and time measurement tests

    International Nuclear Information System (INIS)

    Pechousek, J.; Prochazka, R.; Prochazka, V.; Frydrych, J.

    2011-01-01

    In this report, computer-based digital signal processing system with a 200 MS s -1 sampling digitizer is presented. Virtual instrumentation technique is used to easily develop a system which provides spectroscopy measurements such as amplitude and time signal analysis, with the time-of-flight facility. Several test measurements were performed to determine the characteristics of a system. The presented system may find its application in the coincidence measurement since the system is usable for different types of detectors and sensitive to decay lifetimes from tens of nanoseconds to seconds.

  1. High Spectrum Narrowing Tolerant 112 Gb/s Dual Polarization QPSK Optical Communication Systems Using Digital Adaptive Channel Estimation

    DEFF Research Database (Denmark)

    Zhang, Xu; Pang, Xiaodan; Dogadaev, Anton Konstantinovich

    2012-01-01

    We experimentally demonstrate high spectrum narrowing tolerant 112-Gb/s QPSK polarization multiplex system based on digital adaptive channel estimation method. The proposed algorithm is able to detect severe spectrum-narrowed signal even with 20GHz 3dB bandwidth.......We experimentally demonstrate high spectrum narrowing tolerant 112-Gb/s QPSK polarization multiplex system based on digital adaptive channel estimation method. The proposed algorithm is able to detect severe spectrum-narrowed signal even with 20GHz 3dB bandwidth....

  2. Some important aspects of the amplitude, charge and shape analog signals digitization in nuclear physics experiment

    International Nuclear Information System (INIS)

    Kulka, Z.

    1995-01-01

    One of the fundamental reasons of the special requirements concerning analog-to-digital converters (ADC's) used in nuclear experimental physics, especially in nuclear spectroscopy, in comparison to the conventional ADC's is a fact that they are utilized for continuous distribution measurements which are the nuclear radiation spectra. The ADC's used for distribution registration in form of amplitude or charge histogram spectra should have the differential linearity of two orders of magnitude better than that for conventional ADC's. Moreover, the problem of achievement the acceptable differential linearity (as well as stability) in nuclear spectroscopy is much more complicated because high resolution and high speed of the converters are also required. The first requirement comes out from application of semiconductor detectors, the second one comes from the statistical character of the nuclear processes, as well as, a necessity of collection of huge amount of nuclear data - often in a short time. In this report the influence of the specific needs of the nuclear experiments on the conversion methods selection and construction principles of the pulse ADC's is analyzed. Focus is taken on these ADC's which are used mainly to digital amplitude and charge detector signals measurements in nuclear spectroscopy. Based on the chosen examples of different types of ADC's it is shown how to obtain the required metrological parameters by using enlarged converter's structures and proper choice of the electronics components. In addition, a problem of the detector signals shape measurements in particle physics using the high speed flash ADC's is also discussed. (author). 196 refs, 99 figs, 7 tabs

  3. The single-shot opto-digitizer

    International Nuclear Information System (INIS)

    Nail, M.; Gibert, Ph.

    2000-01-01

    Laser-plasma experiments need to measure signals provided either by X-ray, photonic or neutronic detector. The measurement should have 50 GHz bandwidth and up to several hundred of Giga-Hertz for sub picosecond plasmas. For this purpose, a 35 GHz single shot opto-digitizer (10 ps risetime) has been studied and built. The device is made up of a 50 ohms microstrip propagation line, periodically lined by 100 sampled gates. The propagation line is long enough to measure a 400 ps duration. The sampling rate is 250 Gsa/s (every 4 ps). The sampled gates are made with fast recombining photo-material and turn on by a subpicosecond laser pulse which is synchronized exactly with the analysed phenomena. Every gate is recording to a storing capacitor. After the recording, every capacitor charge is needed to built the signal that was displayed on the propagation line. The dynamic range of measurement is 47 for the entire device. The device can measure positive or negative signals from 1.5 to 70 Volts. To increase the bandwidth, two another kinds of opto-digitizer were studied: one is a buried stripline with 56 GHz band width, the other a 70 GHz coplanar transmission line. For the purpose of subpicosecond plasmas, a 30 coplanar waveguide opto-digitizer was studied. Characteristics are as followed: window of measurement 40 ps, sampling rate 1 ps, bandwidth 230 GHz. Finally, a bundle of optical fibers was used to propagate the laser beam on semiconductor gates. If the gates are lighted at the same time, i.e. if the optical fibers have the same length, we get a simultaneous addressing. By using different lengths of optical fibers, we can do a sequential addressing. So, the sampling rate becomes a combination of the distance between two adjacent sampled channels, and the difference in length of optical fibers. (author)

  4. 14/12-GHz-band satellite communication services

    Science.gov (United States)

    Hayashi, Kunihiro; Nagaki, Kiyoaki; Mori, Yasuo

    1990-01-01

    Three new systems for integrated TV-relay services have been developed: Satellite Video Comunication Service (SVCS) and Satellite Digital Communication Service (SDCS), with Japan's 14/12-GHz-band commercial communication satellites. These systems have been in commercial use since May 1989. Usually SVCS and SDCS have been provided using Ka-band (30/20 GHz-band) of CS-2 and Cs-3. This paper provides an overview of the design, the performance, and the systems of the new 14/12-GHz-band satellite communication services.

  5. GELATIO: a general framework for modular digital analysis of high-purity Ge detector signals

    International Nuclear Information System (INIS)

    Agostini, M; Pandola, L; Zavarise, P; Volynets, O

    2011-01-01

    GELATIO is a new software framework for advanced data analysis and digital signal processing developed for the GERDA neutrinoless double beta decay experiment. The framework is tailored to handle the full analysis flow of signals recorded by high purity Ge detectors and photo-multipliers from the veto counters. It is designed to support a multi-channel modular and flexible analysis, widely customizable by the user either via human-readable initialization files or via a graphical interface. The framework organizes the data into a multi-level structure, from the raw data up to the condensed analysis parameters, and includes tools and utilities to handle the data stream between the different levels. GELATIO is implemented in C++. It relies upon ROOT and its extension TAM, which provides compatibility with PROOF, enabling the software to run in parallel on clusters of computers or many-core machines. It was tested on different platforms and benchmarked in several GERDA-related applications. A stable version is presently available for the GERDA Collaboration and it is used to provide the reference analysis of the experiment data.

  6. Classification of RF transients in space using digital signal processing and neural network techniques

    Energy Technology Data Exchange (ETDEWEB)

    Moore, K.R.; Blain, P.C.; Briles, S.D.; Jones, R.G.

    1995-02-01

    The FORTE{prime} (Fast On-Orbit Recording of Transient Events) small satellite experiment scheduled for launch in October, 1995 will attempt to measure and classify electromagnetic transients as sensed from space. The FORTE{prime} payload will employ an Event Classifier to perform onboard classification of radio frequency transients from terrestrial sources such as lightning. These transients are often dominated by a constantly changing assortment of man-made ``clutter`` such as TV, FM, and radar signals. The FORTE{prime} Event Classifier, or EC, uses specialized hardware to implement various signal processing and neural network algorithms. The resulting system can process and classify digitized records of several thousand samples onboard the spacecraft at rates of about a second per record. In addition to reducing dowlink rates, the EC minimizes command uplink data by normally using uploaded algorithm sequences rather than full code modules (although it is possible for full code modules to be uploaded from the ground). The FORTE{prime} Event Classifier experiment combines science and engineering in an evolutionary step toward useful and robust adaptive processing systems in space.

  7. Robustness of digitally modulated signal features against variation in HF noise model

    Directory of Open Access Journals (Sweden)

    Shoaib Mobien

    2011-01-01

    Full Text Available Abstract High frequency (HF band has both military and civilian uses. It can be used either as a primary or backup communication link. Automatic modulation classification (AMC is of an utmost importance in this band for the purpose of communications monitoring; e.g., signal intelligence and spectrum management. A widely used method for AMC is based on pattern recognition (PR. Such a method has two main steps: feature extraction and classification. The first step is generally performed in the presence of channel noise. Recent studies show that HF noise could be modeled by Gaussian or bi-kappa distributions, depending on day-time. Therefore, it is anticipated that change in noise model will have impact on features extraction stage. In this article, we investigate the robustness of well known digitally modulated signal features against variation in HF noise. Specifically, we consider temporal time domain (TTD features, higher order cumulants (HOC, and wavelet based features. In addition, we propose new features extracted from the constellation diagram and evaluate their robustness against the change in noise model. This study is targeting 2PSK, 4PSK, 8PSK, 16QAM, 32QAM, and 64QAM modulations, as they are commonly used in HF communications.

  8. Analysis and Control of Multi-Bunch Longitudinal Instabilities Using Digital Signal Processing

    Science.gov (United States)

    Fox, John D.

    1996-05-01

    The operation of a longitudinal multi-bunch damping system using digital signal processing techniques is shown via measurements from the LBL Advanced Light Source. The feedback system (developed for use by PEP-II, ALS and DAΦNE) uses a parallel array of signal processors to implement a bunch by bunch feedback system for sampling rates up to 500 MHz. The programmable DSP system allows feedback control as well as accelerator diagnostics. Results are presented showing the action of the system to stabilize the fully populated (320 buckets, 2 ns spacing) ALS machine. The system is shown to increase the intensity and reduce the linewidth of emitted undulator radiation. A diagnostic technique is illustrated which uses the DSP system to excite and then damp the beam. The resulting 12 ms time domain transient is Fourier analyzed to provide the simultaneous measurement of growth rates and damping rates of all coupled-bunch beam modes. Work supported by Department of Energy contract DE-AC03-76SF00515

  9. Digital Receiver-based Electronic Intelligence System Configuration for the Detection and Identification of Intrapulse Modulated Radar Signals

    OpenAIRE

    A. K. Singh; K. Subba Rao

    2014-01-01

    An optimum electronic intelligence system configuration incorporating the state of the art technologies and achieving the highest parameter accuracies while processing the complex intrapulse modulated radar signals is presented in this paper. The system is based on the quad digital receiver, a state of the art single board solution for the detection and analysis of modern radar signals. The system consists of base line interferometry  configuration for high accuracy direction finding measurem...

  10. Re-configurable digital receiver for optically envelope detected half cycle BPSK and MSK radio-on-fiber signals

    DEFF Research Database (Denmark)

    Guerrero Gonzalez, Neil; Prince, Kamau; Zibar, Darko

    2011-01-01

    We present the first known integration of a digital receiver into optically envelope detection radio-on-fiber systems. We also present a re-configurable scheme for two different types of optically envelope detected wireless signals while keeping the complexity of used optical components low. Our ......-shift-keying and 104.17 Mbit/s minimum-shift-keying radio-frequency modulated signals after 30 km of fiber transmission....

  11. Dependable Digitally-Assisted Mixed-Signal IPs Based on Integrated Self-Test & Self-Calibration

    NARCIS (Netherlands)

    Kerkhoff, Hans G.; Wan, J.

    2010-01-01

    Heterogeneous SoC devices, including sensors, analogue and mixed-signal front-end circuits and the availability of massive digital processing capability, are being increasingly used in safety-critical applications like in the automotive, medical, and the security arena. Already a significant amount

  12. Experiment on Synchronous Timing Signal Detection from ISDB-T Terrestrial Digital TV Signal with Application to Autonomous Distributed ITS-IVC Network

    Science.gov (United States)

    Karasawa, Yoshio; Kumagai, Taichi; Takemoto, Atsushi; Fujii, Takeo; Ito, Kenji; Suzuki, Noriyoshi

    A novel timing synchronizing scheme is proposed for use in inter-vehicle communication (IVC) with an autonomous distributed intelligent transport system (ITS). The scheme determines the timing of packet signal transmission in the IVC network and employs the guard interval (GI) timing in the orthogonal frequency divisional multiplexing (OFDM) signal currently used for terrestrial broadcasts in the Japanese digital television system (ISDB-T). This signal is used because it is expected that the automotive market will demand the capability for cars to receive terrestrial digital TV broadcasts in the near future. The use of broadcasts by automobiles presupposes that the on-board receivers are capable of accurately detecting the GI timing data in an extremely low carrier-to-noise ratio (CNR) condition regardless of a severe multipath environment which will introduce broad scatter in signal arrival times. Therefore, we analyzed actual broadcast signals received in a moving vehicle in a field experiment and showed that the GI timing signal is detected with the desired accuracy even in the case of extremely low-CNR environments. Some considerations were also given about how to use these findings.

  13. Early life exposure to 2.45GHz WiFi-like signals: effects on development and maturation of the immune system.

    Science.gov (United States)

    Sambucci, Manolo; Laudisi, Federica; Nasta, Francesca; Pinto, Rosanna; Lodato, Rossella; Lopresto, Vanni; Altavista, Pierluigi; Marino, Carmela; Pioli, Claudio

    2011-12-01

    The development of the immune system begins during embryogenesis, continues throughout fetal life, and completes its maturation during infancy. Exposure to immune-toxic compounds at levels producing limited/transient effects in adults, results in long-lasting or permanent immune deficits when it occurs during perinatal life. Potentially harmful radiofrequency (RF) exposure has been investigated mainly in adult animals or with cells from adult subjects, with most of the studies showing no effects. Is the developing immune system more susceptible to the effects of RF exposure? To address this question, newborn mice were exposed to WiFi signals at constant specific absorption rates (SAR) of 0.08 or 4 W/kg, 2h/day, 5 days/week, for 5 consecutive weeks, starting the day after birth. The experiments were performed with a blind procedure using sham-exposed groups as controls. No differences in body weight and development among the groups were found in mice of both sexes. For the immunological analyses, results on female and male newborn mice exposed during early post-natal life did not show any effects on all the investigated parameters with one exception: a reduced IFN-γ production in spleen cells from microwaves (MW)-exposed (SAR 4 W/kg) male (not in female) mice compared with sham-exposed mice. Altogether our findings do not support the hypothesis that early post-natal life exposure to WiFi signals induces detrimental effects on the developing immune system. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Superconductor Digital-RF Transceiver Components

    National Research Council Canada - National Science Library

    Mukhanov, O; Gupta, D; Kadin, A; Rosa, J; Semenov, V; Filippov, T

    2006-01-01

    .... All of these are based on ultra-fast Rapid Single Flux Quantum (RSFQ) digital circuits, with clock rates up to 20 GHz demonstrated with 3-micron technology, and being scaled to 40 GHz and above...

  15. TFTR 60 GHz alpha particle collective Thomson Scattering diagnostic

    International Nuclear Information System (INIS)

    Machuzak, J.S.; Woskov, P.P.; Gilmore, J.; Bretz, N.L.; Park, H.K.; Bindslev, H.

    1995-03-01

    A 60 GHz gyrotron collective Thomson Scattering alpha particle diagnostic has been implemented for the D-T period on TFM. Gyrotron power of 0.1-1 kW in pulses of up to 1 second can be launched in X-mode. Efficient corrugated waveguides are used with antennaes and vacuum windows of the TFTR Microwave Scattering system. A multichannel synchronous detector receiver system and spectrum analyzer acquire the scattered signals. A 200 Megasample/sec digitizer is used to resolve fine structure in the frequency spectrum. By scattering nearly perpendicular to the magnetic field, this experiment will take advantage of an enhancement of the scattered signal which results from the interaction of the alpha particles with plasma resonances in the lower hybrid frequency range. Significant enhancements are expected, which will make these measurements possible with gyrotron power less than 1 kW, while maintaining an acceptable signal to noise ratio. We hope to extract alpha particle density and velocity distribution functions from the data. The D and T fuel densities and temperatures may also be obtainable by measurement of the respective ion cyclotron harmonic frequencies

  16. Method and apparatus for combinatorial logic signal processor in a digitally based high speed x-ray spectrometer

    International Nuclear Information System (INIS)

    Warburton, W.K.

    1999-01-01

    A high speed, digitally based, signal processing system is disclosed which accepts a digitized input signal and detects the presence of step-like pulses in the this data stream, extracts filtered estimates of their amplitudes, inspects for pulse pileup, and records input pulse rates and system lifetime. The system has two parallel processing channels: a slow channel, which filters the data stream with a long time constant trapezoidal filter for good energy resolution; and a fast channel which filters the data stream with a short time constant trapezoidal filter, detects pulses, inspects for pileups, and captures peak values from the slow channel for good events. The presence of a simple digital interface allows the system to be easily integrated with a digital processor to produce accurate spectra at high count rates and allow all spectrometer functions to be fully automated. Because the method is digitally based, it allows pulses to be binned based on time related values, as well as on their amplitudes, if desired. 31 figs

  17. Digital coherent receiver for phase modulated radio-over-fibre optical links

    DEFF Research Database (Denmark)

    Zibar, Darko; Yu, Xianbin; Peucheret, Christophe

    2009-01-01

    A novel digital signal processing-based coherent receiver for phase-modulated radio-over-fiber (RoF) optical links is presented and demonstrated experimentally. Error-free demodulation of 50-Mbaud binary phase-shift keying (BPSK) and quadrature phase-shift keying data signal modulated on a 5-GHz...... radio-frequency (RF) carrier is experimentally demonstrated using the proposed digital coherent receiver. Additionally, a wavelength-division-multiplexing (WDM) phase-modulated RoF optical link is experimentally demonstrated. A 3 x50 Mb/s WDM transmission of a BPSK modulated 5-GHz RF carrier is achieved...... over 25 km for the WDM channel spacing of 12.5 and 25 GHz, respectively....

  18. Real-Time Digital Signal Processing Based on FPGAs for Electronic Skin Implementation †

    Directory of Open Access Journals (Sweden)

    Ali Ibrahim

    2017-03-01

    Full Text Available Enabling touch-sensing capability would help appliances understand interaction behaviors with their surroundings. Many recent studies are focusing on the development of electronic skin because of its necessity in various application domains, namely autonomous artificial intelligence (e.g., robots, biomedical instrumentation, and replacement prosthetic devices. An essential task of the electronic skin system is to locally process the tactile data and send structured information either to mimic human skin or to respond to the application demands. The electronic skin must be fabricated together with an embedded electronic system which has the role of acquiring the tactile data, processing, and extracting structured information. On the other hand, processing tactile data requires efficient methods to extract meaningful information from raw sensor data. Machine learning represents an effective method for data analysis in many domains: it has recently demonstrated its effectiveness in processing tactile sensor data. In this framework, this paper presents the implementation of digital signal processing based on FPGAs for tactile data processing. It provides the implementation of a tensorial kernel function for a machine learning approach. Implementation results are assessed by highlighting the FPGA resource utilization and power consumption. Results demonstrate the feasibility of the proposed implementation when real-time classification of input touch modalities are targeted.

  19. New method for numerical approximations of vector derivatives based on digital signal processing techniques

    Science.gov (United States)

    Brice, Henry; Ahmed, Mohammed Z.

    2012-05-01

    Accurate propagation models are required for predicting the propagation of electromagnetic waves within complex environments. This paper proposes the use of a new method to accurately compute the divergence and curl of electromagnetic fields. The computation of the derivatives of vector fields is normally approximated using numerical methods such as the Finite-Dierence Time-Domain Method (FDTD), the Finite Integration Technique and the Multi-Resolution Time-Domain Method. These methods are all limited in terms of their accuracy, resolution, computational efficiency and numerical stability. This paper introduces a new method for computing derivatives based on Two-Dimensional (2D) Digital Signal Processing (DSP) techniques. The method involves computing a numerical approximation of the derivative of a function by considering the frequency domain definition of the derivative and designing a 2Dfinite impulse response (FIR) filter that implements the differentiation. Appropriate windowing functions are used to ensure that the FIR response is as close to the ideal 2D differentiator response as possible. This paper provides an example where the curl of a vectorfield is determined using this method and accuracy within a few percent is achieved. The proposed innovative method can be extended to three dimensions and used to find numerical solutions of Maxwells Equations, thus allowing it to be applied to the design of accurate propagation models.

  20. The UTMOST: A Hybrid Digital Signal Processor Transforms the Molonglo Observatory Synthesis Telescope

    Science.gov (United States)

    Bailes, M.; Jameson, A.; Flynn, C.; Bateman, T.; Barr, E. D.; Bhandari, S.; Bunton, J. D.; Caleb, M.; Campbell-Wilson, D.; Farah, W.; Gaensler, B.; Green, A. J.; Hunstead, R. W.; Jankowski, F.; Keane, E. F.; Krishnan, V. Venkatraman; Murphy, Tara; O'Neill, M.; Osłowski, S.; Parthasarathy, A.; Ravi, V.; Rosado, P.; Temby, D.

    2017-10-01

    The Molonglo Observatory Synthesis Telescope (MOST) is an 18000 m2 radio telescope located 40 km from Canberra, Australia. Its operating band (820-851 MHz) is partly allocated to telecommunications, making radio astronomy challenging. We describe how the deployment of new digital receivers, Field Programmable Gate Array-based filterbanks, and server-class computers equipped with 43 Graphics Processing Units, has transformed the telescope into a versatile new instrument (UTMOST) for studying the radio sky on millisecond timescales. UTMOST has 10 times the bandwidth and double the field of view compared to the MOST, and voltage record and playback capability has facilitated rapid implementaton of many new observing modes, most of which operate commensally. UTMOST can simultaneously excise interference, make maps, coherently dedisperse pulsars, and perform real-time searches of coherent fan-beams for dispersed single pulses. UTMOST operates as a robotic facility, deciding how to efficiently target pulsars and how long to stay on source via real-time pulsar folding, while searching for single pulse events. Regular timing of over 300 pulsars has yielded seven pulsar glitches and three Fast Radio Bursts during commissioning. UTMOST demonstrates that if sufficient signal processing is applied to voltage streams, innovative science remains possible even in hostile radio frequency environments.

  1. Real-Time Digital Signal Processing Based on FPGAs for Electronic Skin Implementation.

    Science.gov (United States)

    Ibrahim, Ali; Gastaldo, Paolo; Chible, Hussein; Valle, Maurizio

    2017-03-10

    Enabling touch-sensing capability would help appliances understand interaction behaviors with their surroundings. Many recent studies are focusing on the development of electronic skin because of its necessity in various application domains, namely autonomous artificial intelligence (e.g., robots), biomedical instrumentation, and replacement prosthetic devices. An essential task of the electronic skin system is to locally process the tactile data and send structured information either to mimic human skin or to respond to the application demands. The electronic skin must be fabricated together with an embedded electronic system which has the role of acquiring the tactile data, processing, and extracting structured information. On the other hand, processing tactile data requires efficient methods to extract meaningful information from raw sensor data. Machine learning represents an effective method for data analysis in many domains: it has recently demonstrated its effectiveness in processing tactile sensor data. In this framework, this paper presents the implementation of digital signal processing based on FPGAs for tactile data processing. It provides the implementation of a tensorial kernel function for a machine learning approach. Implementation results are assessed by highlighting the FPGA resource utilization and power consumption. Results demonstrate the feasibility of the proposed implementation when real-time classification of input touch modalities are targeted.

  2. Realization of a digital rate meter as an IIR digital filter by implementing an optimized signal processing algorithm

    Directory of Open Access Journals (Sweden)

    Šaponjić Đorđe

    2009-01-01

    Full Text Available By applying the well known dualism: mean count rate - mean time between successive pulses - the equivalence between an IIR digital filter and a preset count digital rate meter has been demonstrated. By using a bank of four second order IIR filters and an optimized automated algorithm for filter selection, a practical realization of a preset count rate meter giving good tradeoff between statistical fluctuations and speed of response, particularly at low count rates such as background monitoring, is presented. The presented solution is suitable for designing portable count rate meters. The designed prototype is capable of operating up to 3600 pulses per second with an accuracy of over 4% in steady-state and response times of 1 second for the rising edge and 2 seconds for the falling edge of the mean count rate step-change.

  3. Novel ultra-wideband photonic signal generation and transmission featuring digital signal processing bit error rate measurements

    DEFF Research Database (Denmark)

    Gibbon, Timothy Braidwood; Yu, Xianbin; Tafur Monroy, Idelfonso

    2009-01-01

    We propose the novel generation of photonic ultra-wideband signals using an uncooled DFB laser. For the first time we experimentally demonstrate bit-for-bit DSP BER measurements for transmission of a 781.25 Mbit/s photonic UWB signal.......We propose the novel generation of photonic ultra-wideband signals using an uncooled DFB laser. For the first time we experimentally demonstrate bit-for-bit DSP BER measurements for transmission of a 781.25 Mbit/s photonic UWB signal....

  4. A 90 GHz photoinjector

    International Nuclear Information System (INIS)

    Palmer, D.T.; Hogan, M.J.; Ferrario, M.; Serafini, L.

    1999-01-01

    Photocathode rf guns depend on mode locked laser systems to produce an electron beam at a given phase of the rf. In general, the laser pulse is less than σ 2 = 10'' of rf phase in length and the required stability is on the order of Δφ = 1 At 90 GHz (W-band), these requirements correspond to σ 2 = 333 fsec and Δφ = 33 fsec. Laser system with pulse lengths in the fsec regime are commercially available, the timing stability is a major concern. It is proposed a multi-cell W-band photoinjector that does not require a mode locked laser system. Thereby eliminating the stability requirements at W-band. The laser pulse is allowed to be many rf periods long. In principle, the photoinjector can now be considered as a thermionic rf gun. Instead of using an alpha magnet to compress the electron bunch, which would have a detrimental effect on the transverse hase space quality due to longitudinal phase space mixing, it is here proposed to use long pulse laser system and a pair of undulators to produce a low emittance, high current, ultra-short electron bunch for beam dynamics experiments in the 90 GHz regime

  5. Investigation of digital timing resolution and further improvement by using constant fraction signal time marker slope for fast scintillator detectors

    Science.gov (United States)

    Singh, Kundan; Siwal, Davinder

    2018-04-01

    A digital timing algorithm is explored for fast scintillator detectors, viz. LaBr3, BaF2, and BC501A. Signals were collected with CAEN 250 mega samples per second (MSPS) and 500 MSPS digitizers. The zero crossing time markers (TM) were obtained with a standard digital constant fraction timing (DCF) method. Accurate timing information is obtained using cubic spline interpolation of a DCF transient region sample points. To get the best time-of-flight (TOF) resolution, an optimization of DCF parameters is performed (delay and constant fraction) for each pair of detectors: (BaF2-LaBr3), (BaF2-BC501A), and (LaBr3-BC501A). In addition, the slope information of an interpolated DCF signal is extracted at TM position. This information gives a new insight to understand the broadening in TOF, obtained for a given detector pair. For a pair of signals having small relative slope and interpolation deviations at TM, leads to minimum time broadening. However, the tailing in TOF spectra is dictated by the interplay between the interpolation error and slope variations. Best TOF resolution achieved at the optimum DCF parameters, can be further improved by using slope parameter. Guided by the relative slope parameter, events selection can be imposed which leads to reduction in TOF broadening. While the method sets a trade-off between timing response and coincidence efficiency, it provides an improvement in TOF. With the proposed method, the improved TOF resolution (FWHM) for the aforementioned detector pairs are; 25% (0.69 ns), 40% (0.74 ns), 53% (0.6 ns) respectively, obtained with 250 MSPS, and corresponds to 12% (0.37 ns), 33% (0.72 ns), 35% (0.69 ns) respectively with 500 MSPS digitizers. For the same detector pair, event survival probabilities are; 57%, 58%, 51% respectively with 250 MSPS and becomes 63%, 57%, 68% using 500 MSPS digitizers.

  6. Digitized detection of gamma-ray signals concentrated in narrow time windows for transient positron annihilation lifetime spectroscopy.

    Science.gov (United States)

    Kinomura, A; Suzuki, R; Oshima, N; O'Rourke, B E; Nishijima, T; Ogawa, H

    2014-12-01

    A pulsed slow-positron beam generated by an electron linear accelerator was directly used for positron annihilation lifetime spectroscopy without any positron storage devices. A waveform digitizer was introduced to simultaneously capture multiple gamma-ray signals originating from positron annihilation events during a single accelerator pulse. The positron pulse was chopped and bunched with the chopper signals also sent to the waveform digitizer. Time differences between the annihilation gamma-ray and chopper peaks were calculated and accumulated as lifetime spectra in a computer. The developed technique indicated that positron annihilation lifetime spectroscopy can be performed in a 20 μs time window at a pulse repetition rate synchronous with the linear accelerator. Lifetime spectra of a Kapton sheet and a thermally grown SiO2 layer on Si were successfully measured. Synchronization of positron lifetime measurements with pulsed ion irradiation was demonstrated by this technique.

  7. A low power 20 GHz comparator in 90 nm COMS technology

    International Nuclear Information System (INIS)

    Tang Kai; Meng Qiao; Wang Zhigong; Guo Ting

    2014-01-01

    A low power 20 GHz CMOS dynamic latched regeneration comparator for ultra-high-speed, low-power analog-to-digital converters (ADCs) is proposed. The time constant in both the tracking and regeneration phases of the latch are analyzed based on the small signal model. A dynamic source-common logic (SCL) topology is adopted in the master-slave latch to increase the tracking and regeneration speeds. Implemented in 90 nm CMOS technology, this comparator only occupies a die area of 65 × 150 μm 2 with a power dissipation of 14 mW from a 1.2 V power supply. The measurement results show that the comparator can work up to 20 GHz. Operating with an input frequency of 1 GHz, the circuit can oversample up to 20 Giga-sampling-per-second (GSps) with 5 bits resolution; while operating at Nyquist, the comparator can sample up to 20 GSps with 4 bits resolution. The comparator has been successfully used in a 20 GSps flash ADC and the circuit can be also used in other high speed applications. (semiconductor integrated circuits)

  8. Adaptive digital notch filter design on the unit circle for the removal of powerline noise from biomedical signals.

    Science.gov (United States)

    Ferdjallah, M; Barr, R E

    1994-06-01

    This paper investigates adaptive digital notch filters for the elimination of powerline noise from biomedical signals. Since the distribution of the frequency variation of the powerline noise may or may not be centered at 60 Hz, three different adaptive digital notch filters are considered. For the first case, an adaptive FIR second-order digital notch filter is designed to track the center frequency variation. For the second case, the zeroes of an adaptive IIR second-order digital notch filter are fixed on the unit circle and the poles are adapted to find an optimum bandwidth to eliminate the noise to a pre-defined attenuation level. In the third case, both the poles and zeroes of the adaptive IIR second-order filter are adapted to track the center frequency variation within an optimum bandwidth. The adaptive process is considerably simplified by designing the notch filters by pole-zero placement on the unit circle using some suggested rules. A constrained least mean-squared (CLMS) algorithm is used for the adaptive process. To evaluate their performance, the three adaptive notch filters are applied to a powerline noise sample and to a noisy EEG as an illustration of a biomedical signal.

  9. Comparison of three tissue composition measurement techniques using digital mammograms — A signal-to-noise study

    OpenAIRE

    Breitenstein, Darryl S.; Shaw, Chris C.

    1998-01-01

    Tissue composition measurement may provide a quantitatively and physically meaningful method to objectively determine the “mammographic density” linked to breast cancer risk. A single energy hybrid (SEH) technique is described for measuring the tissue composition on a pixel-by-pixel basis with a single digital mammogram. Theoretical models were derived and used to compute signal-to-noise ratios (SNRs) in tissue composition measurement using the SEH method. The results were compared with those...

  10. Propagation considerations for satellite broadcasting at frequencies above 10 GHz

    Science.gov (United States)

    Rogers, D. V.

    1985-01-01

    At frequencies above 10 GHz, tropospheric propagation effects can significantly alter signal transmission performance. Important phenomena on earth-satellite (slant) paths include attenuation and sky noise increases resulting from atmospheric gases, clouds, and precipitation, depolarization by raindrops and ice crystals, and refractive effects, particularly at low path elevation angles. Various practical aspects of propagation phenomena for satellite broadcasting at frequencies above 10 GHz are reviewed in this paper, with emphasis on the near-term implementation of services at Ku-band.

  11. Broadband direct RF digitization receivers

    CERN Document Server

    Jamin, Olivier

    2014-01-01

    This book discusses the trade-offs involved in designing direct RF digitization receivers for the radio frequency and digital signal processing domains.  A system-level framework is developed, quantifying the relevant impairments of the signal processing chain, through a comprehensive system-level analysis.  Special focus is given to noise analysis (thermal noise, quantization noise, saturation noise, signal-dependent noise), broadband non-linear distortion analysis, including the impact of the sampling strategy (low-pass, band-pass), analysis of time-interleaved ADC channel mismatches, sampling clock purity and digital channel selection. The system-level framework described is applied to the design of a cable multi-channel RF direct digitization receiver. An optimum RF signal conditioning, and some algorithms (automatic gain control loop, RF front-end amplitude equalization control loop) are used to relax the requirements of a 2.7GHz 11-bit ADC. A two-chip implementation is presented, using BiCMOS and 65nm...

  12. An SIS Waveguide heterodyne Reciever for 600 GHz - 635 GHz

    Science.gov (United States)

    Salez, Morvan; Febvre, Pascal; McGrath, William R.; Bumble, Bruce; LeDuc, Henry G.

    1994-01-01

    A waveguide SIS heterodyne receiver using a Nb/A10xNb junction has been built for astronomical observations of molecular tranitions in the frequency range 600GHz - 635GHZ, and has been successfully used at the Caltech Submillimeter Observatory (CSO).

  13. Use of Digital Signal Processors (DSP) in high energy physics experiments

    International Nuclear Information System (INIS)

    Crosetto, D.

    1988-01-01

    The FDDP - Fast Digital Data Processor - is a modular system for executing parallel digital processing algorithms to perform programmable trigger decisions or programmable on-line data reduction. Typical application involve zero suppression and pulse shape analysis. The characteristics of the system are: modularity, expandability and flexibility. (author). 4 refs, 5 figs

  14. Digital DC-Reconstruction of AC-Coupled Electrophysiological Signals with a Single Inverting Filter

    DEFF Research Database (Denmark)

    Abächerli, Roger; Isaksen, Jonas; Schmid, Ramun

    2016-01-01

    Since the introduction of digital electrocardiographs, high-pass filters have been necessary for successful analog-to-digital conversion with a reasonable amplitude resolution. On the other hand, such high-pass filters may distort the diagnostically significant ST-segment of the ECG, which can...

  15. Design, analysis, and transmission system performance of a 41 GHz silicon photonic modulator.

    Science.gov (United States)

    Patel, David; Ghosh, Samir; Chagnon, Mathieu; Samani, Alireza; Veerasubramanian, Venkat; Osman, Mohamed; Plant, David V

    2015-06-01

    The design and characterization of a slow-wave series push-pull traveling wave silicon photonic modulator is presented. At 2 V and 4 V reverse bias, the measured -3 dB electro-optic bandwidth of the modulator with an active length of 4 mm are 38 GHz and 41 GHz, respectively. Open eye diagrams are observed up to bitrates of 60 Gbps without any form of signal processing, and up to 70 Gbps with passive signal processing to compensate for the test equipment. With the use of multi-level amplitude modulation formats and digital-signal-processing, the modulator is shown to operate below a hard-decision forward error-correction threshold of 3.8×10-3 at bitrates up to 112 Gbps over 2 km of single mode optical fiber using PAM-4, and over 5 km of optical fiber with PAM-8. Energy consumed solely by the modulator is also estimated for different modulation cases.

  16. Highly linear and transparent 3-18 GHz optical microwave link

    DEFF Research Database (Denmark)

    Nielsen, Torben Nørskov; Gliese, Ulrik Bo; Christensen, T.

    1994-01-01

    A highly linear optical microwave link transmitter based on heterodyne phase-locked DFB lasers is presented. The transmitter is transparent for FM and PM input signals with carrier frequencies ranging from 3-18 GHz. Distortion-free transmission of a 7.6 GHz FM PAL video signal over 25 km of optical...

  17. Performance Evaluation for DFB and VCSEL-based 60 GHz Radio-over-Fiber System

    DEFF Research Database (Denmark)

    Pang, Xiaodan; Lebedev, Alexander; Vegas Olmos, Juan José

    2013-01-01

    In this paper, we report on a detailed analysis and performance comparison work between 60 GHz radio-over-fiber systems based on a DFB laser and a C-band VCSEL. Coherent photonic up-conversion method is applied for the 60 GHz millimeter-wave signal generation. The generated signals are evaluated...

  18. Automatic shape recognition of a fast transient signal

    International Nuclear Information System (INIS)

    Charles, Gilbert.

    1976-01-01

    A system was developed to recognize if the shape of a signal x(t) is similar (or identical) to the one of an element yi(t) of an ensemble S composed by N known signals, that are memorised. x(t) is a time limited T 2 ) give the similarity measure of two signals. To solve the problem of the digital recording of the signals x(t) two devices were realized: a digital-to-analog converter which permits the recording of fast transient signals (band pass>1GHz, sampling-frequency approximately 100GHz, resolution: 9 bits, 576 samples); an automatic attenuator which scales the signal x(t) before the digitalization (the band pass is 70MHz at -1dB). A theoretical analysis permits to determine what must be the resolution of the digital-to-analog converter as a fonction of the signal-caracteristics and of the wanted precision for the calculus of rho 2 [fr

  19. Reconfigurable L-band Radar Transceiver using Digital Signal Synthesis, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase II proposal, builds upon the extensive research and digital radar design that has been successfully completed during the Phase I contract. Key innovations...

  20. Tests of variable-band multilayers designed for investigating optimal signal-to-noise vs artifact signal ratios in Dual-Energy Digital Subtraction Angiography (DDSA) imaging systems

    International Nuclear Information System (INIS)

    Boyers, D.; Ho, A.; Li, Q.; Piestrup, M.; Rice, M.; Tatchyn, R.

    1993-08-01

    In recent work, various design techniques were applied to investigate the feasibility of controlling the bandwidth and bandshape profiles of tungsten/boron-carbon (W/B 4 C) and tungsten/silicon (W/Si) multilayers for optimizing their performance in synchrotron radiation based angiographical imaging systems at 33 keV. Varied parameters included alternative spacing geometries, material thickness ratios, and numbers of layer pairs. Planar optics with nominal design reflectivities of 30%--94% and bandwidths ranging from 0.6%--10% were designed at the Stanford Radiation Laboratory, fabricated by the Ovonic Synthetic Materials Company, and characterized on Beam Line 4-3 at the Stanford Synchrotron Radiation Laboratory, in this paper we report selected results of these tests and review the possible use of the multilayers for determining optimal signal to noise vs. artifact signal ratios in practical Dual-Energy Digital Subtraction Angiography systems

  1. Measurement Results of the Caltech Submillimeter Observatory 230 GHz and 460 GHz Balanced Receivers

    Science.gov (United States)

    Kooi, J. W.; Monje, R. R.; Force, B. L.; Rice, F.; Miller, D.; Phillips, T. G.

    2010-03-01

    The Caltech Submillimeter observatory (CSO) is located on top of Mauna Kea, Hawaii, at an altitude of 4.2km. The existing suite of heterodyne receivers covering the submillimeter band is rapidly aging, and in need of replacement. To this extend we have developed a family of balanced receivers covering the astrophysical important 180-720 GHz atmospheric windows. For the CSO, wide IF bandwidth receivers are implemented in a balanced receiver configuration with dual frequency observation capability. This arrangement was opted to be an optimal compromise between scientific merit and finite funding. In principle, the balanced receiver configuration has the advantage that common mode amplitude noise in the LO system is canceled, while at the same time utilizing all available LO power. Both of these features facilitate the use of commercially available synthesized LO system. In combination with a 4 GHz IF bandwidth, the described receiver layout allows for rapid high resolution spectral line surveys. Dual frequency observation is another important mode of operation offered by the new facility instrumentation. Two band observations are accomplished by separating the H and V polarizations of the incoming signal and routing them via folded optics to the appropriate polarization sensitive balanced mixer. Scientifically this observation mode facilitates pointing for the higher receiver band under mediocre weather conditions and a doubling of scientific throughput (2 x 4 GHz) under good weather conditions. Not only do these changes greatly enhance the spectroscopic capabilities of the CSO, they also enable the observatory to be integrated into the Harvard-Smithsonian Submillimeter Array (eSMA) as an additional baseline. The upgrade of the 345 GHz/650 GHz dual band balanced receivers is not far behind. All the needed hardware has been procured, and commissioning is expected the summer of 2010. The SIS junctions are capable of a 2-12 GHz bandwidth.

  2. Mixed-Signal Architectures for High-Efficiency and Low-Distortion Digital Audio Processing and Power Amplification

    Directory of Open Access Journals (Sweden)

    Pierangelo Terreni

    2010-01-01

    Full Text Available The paper addresses the algorithmic and architectural design of digital input power audio amplifiers. A modelling platform, based on a meet-in-the-middle approach between top-down and bottom-up design strategies, allows a fast but still accurate exploration of the mixed-signal design space. Different amplifier architectures are configured and compared to find optimal trade-offs among different cost-functions: low distortion, high efficiency, low circuit complexity and low sensitivity to parameter changes. A novel amplifier architecture is derived; its prototype implements digital processing IP macrocells (oversampler, interpolating filter, PWM cross-point deriver, noise shaper, multilevel PWM modulator, dead time compensator on a single low-complexity FPGA while off-chip components are used only for the power output stage (LC filter and power MOS bridge; no heatsink is required. The resulting digital input amplifier features a power efficiency higher than 90% and a total harmonic distortion down to 0.13% at power levels of tens of Watts. Discussions towards the full-silicon integration of the mixed-signal amplifier in embedded devices, using BCD technology and targeting power levels of few Watts, are also reported.

  3. A modular, low-cost, digital signal processor-based lock-in card for measuring optical attenuation

    Science.gov (United States)

    Barragán, L. A.; Artigas, J. I.; Alonso, R.; Villuendas, F.

    2001-01-01

    A modular, low-cost, digital signal processor (DSP)-based lock-in card is described for measuring optical attenuation. By transferring the lock-in operation from the analog domain to the digital domain, the nonlinearities gain, and offset errors and drifts are virtually eliminated. The dual phase lock-in operation has been implemented on the low-cost DSP56002 evaluation module (DSP56002EVM) of Motorola that is widely used in audio signal processing. This evaluation board contains a 24 bit DSP56002 DSP and a stereo CD-quality audio codec that makes the board ideal for implementing signal processing algorithms. Due to the maximum sampling rate of the codec embedded on the DSP56002EVM, the frequencies of the processed signals must be below 20 kHz. This specification is enough for the most common applications in the field of optics, where low or very low frequency (<1 kHz) references are frequent. The software algorithm implementing the lock-in amplifier can be particularized by the user on the basis of the needed performances. The effects of finite word length in the digital filter implementation are analyzed. This analysis reveals that a 24 bit word length is not enough to ensure the filter stability and the required frequency response. To overcome this problem, the double precision multiply mode must be used. When the DSP56002 enters this mode, double precision 48 bit by 48 bit multiplication can be performed. The lock-in performance has been tested. The measured amplitude variations of the reference sine signal are about 0.003%, which do not affect the signal measurement. The lock-in behaves like a band-pass filter centered on the reference frequency whose bandwidth is related to the low-pass filter cutoff frequency. The measured frequency response shows that the lock-in performs as theoretically predicted. The DSP56002EVM can be used as a lock-in for electrical signals in stand-alone operation. Besides, we have designed a card that interconnects to the DSP56002EVM

  4. The Digital Data Acquisition System for the Russian VLBI Network of New Generation

    Science.gov (United States)

    Fedotov, Leonid; Nosov, Eugeny; Grenkov, Sergey; Marshalov, Dmitry

    2010-01-01

    The system consists of several identical channels of 1024 MHz bandwidth each. In each channel, the RF band is frequency-translated to the intermediate frequency range 1 - 2 GHz. Each channel consists of two parts: the digitizer and Mark 5C recorder. The digitizer is placed on the antenna close to the corresponding Low-Noise Amplifier output and consists of the analog frequency converter, ADC, and a device for digital processing of the signals using FPGA. In the digitizer the subdigitization on frequency of 2048 MHz is used. For producing narrow-band channels and to interface with existing data acquisition systems, the polyphase filtering with FPGA can be used. Digital signals are re-quantized to 2-bits in the FPGA and are transferred to an input of Mark 5C through a fiber line. The breadboard model of the digitizer is being tested, and the data acquisition system is being designed.

  5. Onboard digital signal processing technologies for present and future TDMA and SCPC systems

    Science.gov (United States)

    Kato, Shuzo; Arita, Takemi; Morita, Kozo

    1987-05-01

    Technologies for onboard TDMA equipment, burst modems, baseband switches, and SCPC multicarrier demodulators from the present to the year 2000 are discussed. Onboard TDMA equipment with a clock rate of lower than 100 MHz can presently be realized by parallel-processed CMOS/BULK LSICs, while for equipment with a clock rate greater than 100 MHz, bipolar devices are more appropriate. For carrier frequencies up to 2 GHz, modem implementation in monolithic microwave ICs is found to be most suitable. Single T-stage and T-S-T architectures are compared as potential baseband configurations. The total weight and power consumption for several suitable onboard SCPC demodulation schemes are investigated as a function of the number of channels to be regenerated.

  6. Low-power digital ASIC for on-chip spectral analysis of low-frequency physiological signals

    International Nuclear Information System (INIS)

    Nie Zedong; Zhang Fengjuan; Li Jie; Wang Lei

    2012-01-01

    A digital ASIC chip customized for battery-operated body sensing devices is presented. The ASIC incorporates a novel hybrid-architecture fast Fourier transform (FFT) unit that is capable of scalable spectral analysis, a licensed ARM7TDMI IP hardcore and several peripheral IP blocks. Extensive experimental results suggest that the complete chip works as intended. The power consumption of the FFT unit is 0.69 mW at 1 MHz with 1.8 V power supply. The low-power and programmable features of the ASIC make it suitable for ‘on-the-fly’ low-frequency physiological signal processing. (semiconductor integrated circuits)

  7. The development of a digital signal processing and plotting package to support testing of hazardous and radioactive material packages

    International Nuclear Information System (INIS)

    Ludwigsen, J.S.; Uncapher, W.L.; Arviso, M.; Lattier, C.N.; Hankinson, M.; Cannone, D.J.

    1995-01-01

    Federal regulations allow package designers to use analysis, testing, or a combination of analysis and testing to support certification of packages used to transport hazardous or radioactive materials. In recent years, many certified packages were subjected to a combination of analysis and testing. A major part of evaluating structural or thermal package response is the collection, reduction and presentation of instrumentation measurement data. Sandia National Laboratories, under the sponsorship of the US Department of Energy, has developed a comprehensive analysis and plotting package (known as KAPP) that performs digital signal processing of both transient structural and thermal data integrated with a comprehensive plotting package designed to support radioactive material package testing

  8. Low-power digital ASIC for on-chip spectral analysis of low-frequency physiological signals

    Science.gov (United States)

    Zedong, Nie; Fengjuan, Zhang; Jie, Li; Lei, Wang

    2012-06-01

    A digital ASIC chip customized for battery-operated body sensing devices is presented. The ASIC incorporates a novel hybrid-architecture fast Fourier transform (FFT) unit that is capable of scalable spectral analysis, a licensed ARM7TDMI IP hardcore and several peripheral IP blocks. Extensive experimental results suggest that the complete chip works as intended. The power consumption of the FFT unit is 0.69 mW @ 1 MHz with 1.8 V power supply. The low-power and programmable features of the ASIC make it suitable for ‘on-the-fly’ low-frequency physiological signal processing.

  9. Frequency diversity wideband digital receiver and signal processor for solid-state dual-polarimetric weather radars

    Science.gov (United States)

    Mishra, Kumar Vijay

    The recent spate in the use of solid-state transmitters for weather radar systems has unexceptionably revolutionized the research in meteorology. The solid-state transmitters allow transmission of low peak powers without losing the radar range resolution by allowing the use of pulse compression waveforms. In this research, a novel frequency-diversity wideband waveform is proposed and realized to extenuate the low sensitivity of solid-state radars and mitigate the blind range problem tied with the longer pulse compression waveforms. The latest developments in the computing landscape have permitted the design of wideband digital receivers which can process this novel waveform on Field Programmable Gate Array (FPGA) chips. In terms of signal processing, wideband systems are generally characterized by the fact that the bandwidth of the signal of interest is comparable to the sampled bandwidth; that is, a band of frequencies must be selected and filtered out from a comparable spectral window in which the signal might occur. The development of such a wideband digital receiver opens a window for exciting research opportunities for improved estimation of precipitation measurements for higher frequency systems such as X, Ku and Ka bands, satellite-borne radars and other solid-state ground-based radars. This research describes various unique challenges associated with the design of a multi-channel wideband receiver. The receiver consists of twelve channels which simultaneously downconvert and filter the digitized intermediate-frequency (IF) signal for radar data processing. The product processing for the multi-channel digital receiver mandates a software and network architecture which provides for generating and archiving a single meteorological product profile culled from multi-pulse profiles at an increased data date. The multi-channel digital receiver also continuously samples the transmit pulse for calibration of radar receiver gain and transmit power. The multi

  10. Digital Signal Processing for a Sliceable Transceiver for Optical Access Networks

    DEFF Research Database (Denmark)

    Saldaña Cercos, Silvia; Wagner, Christoph; Vegas Olmos, Juan José

    2015-01-01

    Methods to upgrade the network infrastructure to cope with current traffic demands has attracted increasing research efforts. A promising alternative is signal slicing. Signal slicing aims at re-using low bandwidth equipment to satisfy high bandwidth traffic demands. This technique has been used ...... penalty is reported for 10 Gbps. Power savings of the order of hundreds of Watts can be obtained when using signal slicing as an alternative to 10 Gbps implemented access networks....

  11. A Methodology to Teach Advanced A/D Converters, Combining Digital Signal Processing and Microelectronics Perspectives

    Science.gov (United States)

    Quintans, C.; Colmenar, A.; Castro, M.; Moure, M. J.; Mandado, E.

    2010-01-01

    ADCs (analog-to-digital converters), especially Pipeline and Sigma-Delta converters, are designed using complex architectures in order to increase their sampling rate and/or resolution. Consequently, the learning of ADC devices also encompasses complex concepts such as multistage synchronization, latency, oversampling, modulation, noise shaping,…

  12. Digital Semaphore: Technical Feasibility of QR Code Optical Signaling for Fleet Communications

    Science.gov (United States)

    2013-06-01

    communication to be used in conjunction with existing RF technologies. This work has fundamental implications for naval warfare. Literature review to date has...eliminates camera blur induced by the shutter, providing clear images at extremely high frame rates. Thusly, digital cinema cameras are more suitable

  13. Electromagnetic signals generated in the solid Earth by digital transmission of radio-waves as a plausible source for some so-called `seismic electric signals'

    Science.gov (United States)

    Pham, V.-N.; Boyer, D.; Le Mouël, J.-L.; Chouliaras, G.; Stavrakakis, G. N.

    1999-07-01

    Claims by the VAN group [Varotsos, P., Alexopoulos, K., 1984. Physical properties of the variations of the electric field of the earth preceding earthquakes, I. Tectonophysics 110, 73-98, and later works] to have developed a short-term earthquake prediction technique in Greece continue to arouse contentious debates [Claims of success in using geoelectrical precursors to predict earthquakes are criticized and defended, 1998. Letters, Phys. Today 51 (6), 15-100; Great debates in seismology: the VAN method of earthquake prediction, 1998. Eos 79, 573-580]. This is partly because of the unknown origin of the so-called `seismic electric signals' (SES) precursors. Their particular characteristics are not those of the usual electromagnetic noise (cultural noise) or of the natural electromagnetic field (magnetotelluric field). In this paper, we show that transient electric signals looking like SES can be generated by digital transmitters of the radio-telecommunication network. Such signals have been observed in different regions of the world, including Greece and Vietnam. Their characteristics have been analyzed in a broad band of frequencies (10 -3-10 3 Hz) in the Ioannina, Greece, site which is considered as the most `sensitive area' of the VAN network. It is concluded that some of the signals recorded at this site and identified as SES are probably of artificial origin, and that the criteria used by the VAN group are not sufficient to guarantee that the so-called SES are not man-made. Without an extended and thorough study of the ambient electromagnetic noise in a broad band of frequencies and better information about the electrical properties of the deep structure beneath the monitoring station, earthquake predictions issued on the basis of signals recorded by the VAN network are of dubious significance.

  14. Optical Signal Processing; a novel approach to modifying digital information in optical domain

    NARCIS (Netherlands)

    Rijnders, J.M.

    1998-01-01

    It is concluded that the OSP offers a new and alternative method for manipulating and modifying data in the optical domain. Under certain circumstances during signal processing, a number of signal properties such as wavelength and modulation format can be preserved. Interesting applications can be

  15. MAS2-8 radar and digital control unit

    Science.gov (United States)

    Oberg, J. M.; Ulaby, F. T.

    1974-01-01

    The design of the MAS 2-8 (2 to 8 GHz microwave-active spectrometer), a ground-based sensor system, is presented. A major modification in 1974 to the MAS 2-8, that of a control subsystem to automate the data-taking operation, is the prime focus. The digital control unit automatically changes all system parameters except FM rate and records the return signal on paper tape. The overall system operation and a detailed discussion of the design and operation of the digital control unit are presented.

  16. JPL 2-to-the-20th-power channel 300 MHz bandwidth digital spectrum analyzer

    Science.gov (United States)

    Morris, G. A., Jr.; Wilck, H. C.

    1978-01-01

    A million (two to the 20th power) channel, 300 MHz bandwidth, digital spectrum analyzer was considered. The design, fabrication, and maintenance philosophy of the modular, pipelined, fast fourier transform (FFT) hardware are described. The spectrum analyzer will be used to examine the region from 1.4 GHz to 26 GHz for radio frequency interference which may be harmful to present and future tracking missions of the Deep Space Network. The design has application to the search for extraterrestrial intelligence signals and radio science phenomena.

  17. Digital signal processor-based high-precision on-line Voigt lineshape fitting for direct absorption spectroscopy.

    Science.gov (United States)

    Xu, Lijun; Liu, Chang; Zheng, Deyan; Cao, Zhang; Cai, Weiwei

    2014-12-01

    To realize on-line high-accuracy measurement in direct absorption spectroscopy (DAS), a system-on-chip, high-precision digital signal processor-based on-line Voigt lineshape fitting implementation is introduced in this paper. Given that the Voigt lineshape is determined by the Gauss full width at half maximum (FWHM) and Lorentz FWHM, a look-up table, which covers a range of combinations of both, is first built to achieve rapid and accurate calculation of Voigt lineshape. With the look-up table and raw absorbance data in hand, Gauss-Newton nonlinear fitting module is implemented to obtain the parameters including both the Gauss and Lorentz FWHMs, which can be used to calculate the integrated absorbance. To realize the proposed method in hardware, a digital signal processor (DSP) is adopted to fit the Voigt lineshape in a real-time DAS measurement system. In experiment, temperature and H2O concentration of a flat flame are recovered from the transitions of 7444.36 cm(-1) and 7185.6 cm(-1) by the DSP-based on-line Voigt lineshape fitting and on-line integral of the raw absorbance, respectively. The results show that the proposed method can not only fit the Voigt lineshape on-line but also improve the measurement accuracy compared with those obtained from the direct integral of the raw absorbance.

  18. Obstacle Avoidance and Target Acquisition for Robot Navigation Using a Mixed Signal Analog/Digital Neuromorphic Processing System

    Directory of Open Access Journals (Sweden)

    Moritz B. Milde

    2017-07-01

    Full Text Available Neuromorphic hardware emulates dynamics of biological neural networks in electronic circuits offering an alternative to the von Neumann computing architecture that is low-power, inherently parallel, and event-driven. This hardware allows to implement neural-network based robotic controllers in an energy-efficient way with low latency, but requires solving the problem of device variability, characteristic for analog electronic circuits. In this work, we interfaced a mixed-signal analog-digital neuromorphic processor ROLLS to a neuromorphic dynamic vision sensor (DVS mounted on a robotic vehicle and developed an autonomous neuromorphic agent that is able to perform neurally inspired obstacle-avoidance and target acquisition. We developed a neural network architecture that can cope with device variability and verified its robustness in different environmental situations, e.g., moving obstacles, moving target, clutter, and poor light conditions. We demonstrate how this network, combined with the properties of the DVS, allows the robot to avoid obstacles using a simple biologically-inspired dynamics. We also show how a Dynamic Neural Field for target acquisition can be implemented in spiking neuromorphic hardware. This work demonstrates an implementation of working obstacle avoidance and target acquisition using mixed signal analog/digital neuromorphic hardware.

  19. Real-time digital signal recovery for a multi-pole low-pass transfer function system

    Science.gov (United States)

    Lee, Jhinhwan

    2017-08-01

    In order to solve the problems of waveform distortion and signal delay by many physical and electrical systems with multi-pole linear low-pass transfer characteristics, a simple digital-signal-processing (DSP)-based method of real-time recovery of the original source waveform from the distorted output waveform is proposed. A mathematical analysis on the convolution kernel representation of the single-pole low-pass transfer function shows that the original source waveform can be accurately recovered in real time using a particular moving average algorithm applied on the input stream of the distorted waveform, which can also significantly reduce the overall delay time constant. This method is generalized for multi-pole low-pass systems and has noise characteristics of the inverse of the low-pass filter characteristics. This method can be applied to most sensors and amplifiers operating close to their frequency response limits to improve the overall performance of data acquisition systems and digital feedback control systems.

  20. Digital signal processing for the Johnson noise thermometry: a time series analysis of the Johnson noise

    International Nuclear Information System (INIS)

    Moon, Byung Soo; Hwang, In Koo; Chung, Chong Eun; Kwon, Kee Choon; David, E. H.; Kisner, R.A.

    2004-06-01

    In this report, we first proved that a random signal obtained by taking the sum of a set of signal frequency signals generates a continuous Markov process. We used this random signal to simulate the Johnson noise and verified that the Johnson noise thermometry can be used to improve the measurements of the reactor coolant temperature within an accuracy of below 0.14%. Secondly, by using this random signal we determined the optimal sampling rate when the frequency band of the Johnson noise signal is given. Also the results of our examination on how good the linearity of the Johnson noise is and how large the relative error of the temperature could become when the temperature increases are described. Thirdly, the results of our analysis on a set of the Johnson noise signal blocks taken from a simple electric circuit are described. We showed that the properties of the continuous Markov process are satisfied even when some channel noises are present. Finally, we describe the algorithm we devised to handle the problem of the time lag in the long-term average or the moving average in a transient state. The algorithm is based on the Haar wavelet and is to estimate the transient temperature that has much smaller time delay. We have shown that the algorithm can track the transient temperature successfully

  1. Design and Development of Amplitude and phase measurement of RF signal with Digital I-Q Demodulator

    Science.gov (United States)

    Soni, Dipal; Rajnish, Kumar; Verma, Sriprakash; Patel, Hriday; Trivedi, Rajesh; Mukherjee, Aparajita

    2017-04-01

    ITER-India, working as a nodal agency from India for ITER project [1], is responsible to deliver one of the packages, called Ion Cyclotron Heating & Current Drive (ICH&CD) - Radio Frequency Power Sources (RFPS). RFPS is having two cascaded amplifier chains (10 kW, 130 kW & 1.5 MW) combined to get 2.5 MW RF power output. Directional couplers are inserted at the output of each stage to extract forward power and reflected power as samples for measurement of amplitude and phase. Using passive mixer, forward power and reflected power are down converted to 1MHz Intermediate frequency (IF). This IF signal is used as an input to the Digital IQ Demodulator (DIQDM). DIQDM is realized using National Instruments make PXI hardware & LabVIEW software tool. In this paper, Amplitude and Phase measurement of RF signal with DIQDM technique is described. Also test results with dummy signals and signal generated from low power RF systems is discussed here.

  2. Small-signal modeling of digitally controlled grid-connected inverters with LCL filters

    DEFF Research Database (Denmark)

    Zhang, Xiaotian; W. Spencer, Joseph; Guerrero, Josep M.

    2013-01-01

    When LCL filters are applied to digitally controlled grid-connected inverters, the design of controllers is usually implemented using classic average models. The accuracy of these models in s-domain is only guaranteed in low frequency range. In order to predict the dynamic behaviors, new smallsig......When LCL filters are applied to digitally controlled grid-connected inverters, the design of controllers is usually implemented using classic average models. The accuracy of these models in s-domain is only guaranteed in low frequency range. In order to predict the dynamic behaviors, new...... in predicting instabilities. Experimental results are presented and compared to the average models predictions and z-domain models predictions, which shows the proposed models are capable of predicting the values of control variables at the true sampling instants....

  3. A Digital Signal Processing Method for Gene Prediction with Improved Noise Suppression

    Directory of Open Access Journals (Sweden)

    Carreira Alex

    2004-01-01

    Full Text Available It has been observed that the protein-coding regions of DNA sequences exhibit period-three behaviour, which can be exploited to predict the location of coding regions within genes. Previously, discrete Fourier transform (DFT and digital filter-based methods have been used for the identification of coding regions. However, these methods do not significantly suppress the noncoding regions in the DNA spectrum at . Consequently, a noncoding region may inadvertently be identified as a coding region. This paper introduces a new technique (a single digital filter operation followed by a quadratic window operation that suppresses nearly all of the noncoding regions. The proposed method therefore improves the likelihood of correctly identifying coding regions in such genes.

  4. A novel demodulator/detector for digital and analog signals on LMR channels

    Science.gov (United States)

    Saulnier, Gary J.; Rafferty, William

    1990-01-01

    The design, implementation, and performance of an all-digital demodulator/detector suitable for differentially encoded phase-shift keying (DPSK), continuous-phase frequency-shift keying (CPFSK), frequency-shift keying (FSK), and analog FM are discussed. In this demodulator/detector, two detectors, one noncoherent and another differentially coherent, operate simultaneously to provide data detection and automatic frequency control (AFC). Test results indicate that the system provides improved performance over the conventional analog quadrature detector for two-period raised-cosine (2RC) CPFSK modulation in additive white Gaussian noise (AWGN) and Rayleigh fading channels. Being all-digital, the demodulator/detector is well suited for integrated circuit implementation. In addition, the system performs as well as the analog quadrature detector for analog FM voice transmissions, thereby maintaining full compatibility with analog land mobile radio (LMR) transmissions.

  5. An effective coded excitation scheme based on a predistorted FM signal and an optimized digital filter

    DEFF Research Database (Denmark)

    Misaridis, Thanasis; Jensen, Jørgen Arendt

    1999-01-01

    This paper presents a coded excitation imaging system based on a predistorted FM excitation and a digital compression filter designed for medical ultrasonic applications, in order to preserve both axial resolution and contrast. In radars, optimal Chebyshev windows efficiently weight a nearly...... is applied on receive, contrast or resolution can be traded in for range sidelobe levels down to -86 dB. The digital filter is designed to efficiently use the available bandwidth and at the same time to be insensitive to the transducer's impulse response. For evaluation of the method, simulations were...... performed with the program Field II. A commercial scanner (B-K Medical 3535) was modified and interfaced to an arbitrary function generator along with an RF power amplifier (Ritec). Hydrophone measurements in water were done to establish excitation voltage and corresponding intensity levels (I-sptp and I...

  6. [Improved detection of the pulse oximeter signal with a digital nerve block in patients in poor health status].

    Science.gov (United States)

    Cordoví de Armas, L; Espinaco Valdés, J; Jiménez Paneque, R E; Costa Hidalgo, T; Vallongo Menéndez, M B

    2008-10-01

    To demonstrate the efficacy of a digital nerve block for improving pulse oximetry in conditions of low tissue perfusion. A randomized single-blind study of adult patients undergoing surgery under general anesthesia for conditions characterized by hypoperfusion. Patients were assigned to a control group or an experimental group. The experimental group received a digital nerve block in the middle finger of the left hand; a sensor was then placed on the finger for between 120 and 300 minutes. Age, sex, diagnosis, total observation time (TOT), percentage of time with no pulse oximeter signal (NoPO), and percentage of time with an unstable pulse oximeter signal (UnstPO) were recorded. Each patient was questioned between 16 and 24 hours after surgery and was examined for flushing, paresthesia, hypoesthesia, pain, and ecchymosis. The chi2 test was used to compare dichotomized or nominal variables and the t test was used to compare age, TOT, NoPO, and UnstPO. Values of P<.05 were considered statistically significant in both cases. Fifty patients were randomized to each group. A total of 82 patients remained in the study (control group=42, experimental group=40). There were no significant between-group differences in diagnoses or TOT. The mean values for NoPO and UnstPO were higher in the control group than in the experimental group (11.1% vs 4.4% and 35.9% vs 15.7%, respectively; P<.001). A digital nerve block can be used to prevent pulse oximetry failures in conditions of low peripheral perfusion.

  7. The DECMU: a digital device for delayed analysis of multi-frequency eddy current signals

    International Nuclear Information System (INIS)

    Pigeon, Michel.

    1981-08-01

    A delayed data analysis system has been realized by the CEA and Intercontrole for in-service inspection of steam generators of nuclear plants by multifrequency eddy current testing. This device allows, out of the plant, adjustment during switching of the probes, graph recording and analysis for defect signal qualification. The equipment contains an analog mixing device, as IC3FA multi-frequency appartus, but has in addition a memory allowing data cycling and signal isolation for adjustment or analysis [fr

  8. Superconducting Complementary Output Switching Logic Operating at 10 - 18 GHz

    Science.gov (United States)

    Jeffery, Mark; van Duzer, T.; Perold, Willem

    1998-03-01

    We have developed a new type of superconducting voltage-state logic called Complementary Output Switching Logic (COSL)(M. Jeffery, W. Perold, and T. Van Duzer, Appl. Phys. Lett., 69) (18), 2746 (1996). The basic COSL gates have been demonstrated at 10 GHz and complex 2-bit encoder circuits have operated at 5 - 8 GHz. The COSL gates have extremely low power dissipation, of order 10 μW/gate, and we have measured bit error rates less than 10-12 at 2 GHz. For these results we used the HYPRES 1 kA/cm^2 critical current density Nb Josephson fabrication process. In the present work we describe our recent test results using the new HYPRES 2.5 kA/cm^2 process. The increased critical current density process significantly improves the switching speed of the COSL devices. We will describe the Monte Carlo method used to optimize the COSL gates for 20 - 30 GHz operation, and the optimal circuit layouts including moats, or ground plane holes, to shield the circuits from trapped magnetic flux. Experimental test results will be presented for the basic COSL devices operating at 10 - 18 GHz. These are the fastest superconducting voltage-state logic devices ever reported, and may have many applications in low power ultra-high-speed digital systems of the future.

  9. Arbitrary waveform modulated pulse EPR at 200 GHz

    Science.gov (United States)

    Kaminker, Ilia; Barnes, Ryan; Han, Songi

    2017-06-01

    We report here on the implementation of arbitrary waveform generation (AWG) capabilities at ∼200 GHz into an Electron Paramagnetic Resonance (EPR) and Dynamic Nuclear Polarization (DNP) instrument platform operating at 7 T. This is achieved with the integration of a 1 GHz, 2 channel, digital to analog converter (DAC) board that enables the generation of coherent arbitrary waveforms at Ku-band frequencies with 1 ns resolution into an existing architecture of a solid state amplifier multiplier chain (AMC). This allows for the generation of arbitrary phase- and amplitude-modulated waveforms at 200 GHz with >150 mW power. We find that the non-linearity of the AMC poses significant difficulties in generating amplitude-modulated pulses at 200 GHz. We demonstrate that in the power-limited regime of ω1 10 MHz) spin manipulation in incoherent (inversion), as well as coherent (echo formation) experiments. Highlights include the improvement by one order of magnitude in inversion bandwidth compared to that of conventional rectangular pulses, as well as a factor of two in improvement in the refocused echo intensity at 200 GHz.

  10. Dual beam vidicon digitizer

    International Nuclear Information System (INIS)

    Evans, T.L.

    1976-01-01

    A vidicon waveform digitizer which can simultaneously digitize two independent signals has been developed. Either transient or repetitive waveforms can be digitized with this system. A dual beam oscilloscope is used as the signal input device. The light from the oscilloscope traces is optically coupled to a television camera, where the signals are temporarily stored prior to digitizing

  11. Sideband Separating Mixer for 600-720 GHz

    NARCIS (Netherlands)

    Khudchenko, Andrey; Hesper, Ronald; Barychev, Andrey; Gerlofma, Gerrit; Mena, Patricio; Zijlstra, Tony; Klapwijk, Teun; Spaans, Marco; Kooi, Jacob W.; Zhang, C; Zhang, XC; Siegel, PH; He, L; Shi, SC

    2010-01-01

    The ALMA Band 9 receiver cartridge (600-720 GHz) based on Dual Sideband (DSB) superconductor-insulator-superconductor (SIS) mixer is currently in full production. In the case of spectral line observations, the integration time to reach a certain signal-to-noise level can be reduced by about a factor

  12. Impact of laminitis on the canonical Wnt signaling pathway in basal epithelial cells of the equine digital laminae.

    Science.gov (United States)

    Wang, Le; Pawlak, Erica A; Johnson, Philip J; Belknap, James K; Eades, Susan; Stack, Sharon; Cousin, Helene; Black, Samuel J

    2013-01-01

    The digital laminae is a two layer tissue that attaches the distal phalanx to the inner hoof wall, thus suspending the horse's axial skeleton in the hoof capsule. This tissue fails at the epidermal:dermal junction in laminitic horses, causing crippling disease. Basal epithelial cells line the laminar epidermal:dermal junction, undergo physiological change in laminitic horses, and lose versican gene expression. Versican gene expression is purportedly under control of the canonical Wnt signaling pathway and is a trigger for mesenchymal-to-epithelial transition; thus, its repression in laminar epithelial cells of laminitic horses may be associated with suppression of the canonical Wnt signaling pathway and loss of the epithelial cell phenotype. In support of the former contention, we show, using laminae from healthy horses and horses with carbohydrate overload-induced laminitis, quantitative real-time polymerase chain reaction, Western blotting after sodium dodecylsulfate polyacrylamide gel electrophoresis, and immunofluorescent tissue staining, that positive and negative regulatory components of the canonical Wnt signaling pathway are expressed in laminar basal epithelial cells of healthy horses. Furthermore, expression of positive regulators is suppressed and negative regulators elevated in laminae of laminitic compared to healthy horses. We also show that versican gene expression in the epithelial cells correlates positively with that of β-catenin and T-cell Factor 4, consistent with regulation by the canonical Wnt signaling pathway. In addition, gene and protein expression of β-catenin correlates positively with that of integrin β4 and both are strongly suppressed in laminar basal epithelial cells of laminitic horses, which remain E-cadherin(+)/vimentin(-), excluding mesenchymal transition as contributing to loss of the adherens junction and hemidesmosome components. We propose that suppression of the canonical Wnt signaling pathway, and accompanying reduced

  13. Impact of laminitis on the canonical Wnt signaling pathway in basal epithelial cells of the equine digital laminae.

    Directory of Open Access Journals (Sweden)

    Le Wang

    Full Text Available The digital laminae is a two layer tissue that attaches the distal phalanx to the inner hoof wall, thus suspending the horse's axial skeleton in the hoof capsule. This tissue fails at the epidermal:dermal junction in laminitic horses, causing crippling disease. Basal epithelial cells line the laminar epidermal:dermal junction, undergo physiological change in laminitic horses, and lose versican gene expression. Versican gene expression is purportedly under control of the canonical Wnt signaling pathway and is a trigger for mesenchymal-to-epithelial transition; thus, its repression in laminar epithelial cells of laminitic horses may be associated with suppression of the canonical Wnt signaling pathway and loss of the epithelial cell phenotype. In support of the former contention, we show, using laminae from healthy horses and horses with carbohydrate overload-induced laminitis, quantitative real-time polymerase chain reaction, Western blotting after sodium dodecylsulfate polyacrylamide gel electrophoresis, and immunofluorescent tissue staining, that positive and negative regulatory components of the canonical Wnt signaling pathway are expressed in laminar basal epithelial cells of healthy horses. Furthermore, expression of positive regulators is suppressed and negative regulators elevated in laminae of laminitic compared to healthy horses. We also show that versican gene expression in the epithelial cells correlates positively with that of β-catenin and T-cell Factor 4, consistent with regulation by the canonical Wnt signaling pathway. In addition, gene and protein expression of β-catenin correlates positively with that of integrin β4 and both are strongly suppressed in laminar basal epithelial cells of laminitic horses, which remain E-cadherin(+/vimentin(-, excluding mesenchymal transition as contributing to loss of the adherens junction and hemidesmosome components. We propose that suppression of the canonical Wnt signaling pathway, and

  14. 78 FR 59844 - Operation in the 57-64 GHz Band

    Science.gov (United States)

    2013-09-30

    ... digital systems in the 60 GHz band without increasing the potential for harmful interference, the... replace digital subscriber line (DSL) and cable modem broadband services, because the high cost of the point-to- point devices would preclude their off-the-shelf retail marketing to consumers. Therefore, out...

  15. A digital phase locked loop based signal and symbol recovery system for wireless channel

    CERN Document Server

    Purkayastha, Basab Bijoy

    2015-01-01

    The book reports two approaches of implementation of the essential components of a Digital Phase Locked Loop based system for dealing with wireless channels showing Nakagami-m fading. It is mostly observed in mobile communication. In the first approach, the structure of a Digital phase locked loop (DPLL) based on Zero Crossing (ZC) algorithm is proposed. In a modified form, the structure of a DPLL based systems for dealing with Nakagami-m fading based on Least Square Polynomial Fitting Filter is proposed, which operates at moderate sampling frequencies. A sixth order Least Square Polynomial Fitting (LSPF) block and Roots Approximator (RA) for better phase-frequency detection has been implemented as a replacement of Phase Frequency Detector (PFD) and Loop Filter (LF) of a traditional DPLL, which has helped to attain optimum performance of DPLL. The results of simulation of the proposed DPLL with Nakagami-m fading and QPSK modulation is discussed in detail which shows that the proposed method provides better pe...

  16. Digital signal processing in ultrasonic based navigation system for mobile robots

    Directory of Open Access Journals (Sweden)

    Stączek Paweł

    2017-01-01

    Full Text Available A system for estimating the coordinates of automated guided vehicles (AGV was presented in this article. Ultrasonic waves for distance measurement were applied. Used hardware was characterised, as well as signal processing algorithms. The system was tested on wheeled mobile robot in model 2D environment. The results of working range and errors of position estimation were discussed.

  17. Robust 9-QAM digital recovery for spectrum shaped coherent QPSK signal

    DEFF Research Database (Denmark)

    Huang, Bo; Zhang, Junwen; Yu, Jianjun

    2013-01-01

    We propose 9-ary quadrature amplitude modulation (9-QAM) data recovery for polarization multiplexing-quadrature phase shift keying (PM-QPSK) signal in presence of strong filtering to approach Nyquist bandwidth. The decision-directed least radius distance (DD-LRD) algorithm for blind equalization ...

  18. Molecular Spectroscopy With a Compact 557-GHz Heterodyne Receiver

    DEFF Research Database (Denmark)

    Neumaier, Philipp F.-X.; Richter, Heiko; Stake, Jan

    2014-01-01

    We report on a heterodyne terahertz spectrometer based on a fully integrated 557-GHz receiver and a digital fast Fourier transform spectrometer. The receiver consists of a chain of multipliers and power amplifiers, followed by a heterostructure barrier varactor tripler that subharmonically pumps ...... of methanol absorption lines were determined, that agree with other published data. Using the experimentally determined molecular parameters the CH3OH absorption spectrum could be modeled with very high precision....

  19. Molecular Spectroscopy With a Compact 557-GHz Heterodyne Receiver

    OpenAIRE

    Neumaier, Philipp F.-X.; Richter, Heiko; Stake, Jan; Zhao, Huan; Tang, Aik-Yean; Drakinskiy, Vladimir; Sobis, Peter; Emrich, Anders; Hülsmann, Axel; Johansen, Tom K.; Bryllert, Tomas; Hanning, Johanna; Krozer, Viktor; Hübers, Heinz-Wilhelm

    2014-01-01

    We report on a heterodyne terahertz spectrometer based on a fully integrated 557-GHz receiver and a digital fast Fourier transform spectrometer. The receiver consists of a chain of multipliers and power amplifiers, followed by a heterostructure barrier varactor tripler that subharmonically pumps a membrane GaAs Schottky diode mixer. All sub-components are newly developed and optimized with regard to the overall receiver performance such as noise temperature, power consumption, weight and phys...

  20. Signal processing: opportunities for superconductive circuits

    International Nuclear Information System (INIS)

    Ralston, R.W.

    1985-01-01

    Prime motivators in the evolution of increasingly sophisticated communication and detection systems are the needs for handling ever wider signal bandwidths and higher data processing speeds. These same needs drive the development of electronic device technology. Until recently the superconductive community has been tightly focused on digital devices for high speed computers. The purpose of this paper is to describe opportunities and challenges which exist for both analog and digital devices in a less familiar area, that of wideband signal processing. The function and purpose of analog signal-processing components, including matched filters, correlators and Fourier transformers, will be described and examples of superconductive implementations given. A canonic signal-processing system is then configured using these components in combination with analog/digital converters and digital output circuits to highlight the important issues of dynamic range, accuracy and equivalent computation rate. Superconductive circuits hold promise for processing signals of 10-GHz bandwidth. Signal processing systems, however, can be properly designed and implemented only through a synergistic combination of the talents of device physicists, circuit designers, algorithm architects and system engineers. An immediate challenge to the applied superconductivity community is to begin sharing ideas with these other researchers

  1. CMOS time-to-digital converters for mixed-mode signal processing

    Directory of Open Access Journals (Sweden)

    Fei Yuan

    2014-04-01

    Full Text Available This study provides an in-depth review of the principles, architectures and design techniques of CMOS time-to-digital converters (TDCs. The classification of TDCs is introduced. It is followed by the examination of the parameters quantifying the performance of TDCs. Sampling TDCs including direct-counter TDCs, tapped delay-line TDCs, pulse-shrinking delay-line TDCs, cyclic pulse-shrinking TDCs, direct-counter TDCs with interpolation, vernier TDCs, flash TDCs, successive approximation TDCs and pipelined TDCs are studied and their pros and cons are compared. Noise-shaping TDCs that reduce in-band noise below technology limit are investigated. These TDCs include gated ring oscillator TDCs, switched ring oscillator TDCs, relaxation oscillator TDCs, ΔΣ TDCs and MASH TDCs. The performance of sampling and noise-shaping TDCs is compared. The direction of future research on TDCs is explored.

  2. FD-TD modeling of digital signal propagation in 3-D circuits with passive and active loads

    Science.gov (United States)

    Piket-May, Melinda; Taflove, Allen; Baron, John

    1994-08-01

    Most existing computer-aided circuit design tools are limited when digital clock speeds exceed several hundred MHz. These tools may not deal effectively with the physics of UHF and microwave electromagnetic wave energy transport along metal surfaces such as ground planes or in the air away from metal paths that are common at or above this frequency range. In this paper, we discuss full-wave modeling of electronic circuits in three dimensions using the finite-difference time-domain (FD-TD) solution of Maxwell's equations. Parameters such as stripline complex line impedance, propagation constant, capacitance per unit length and inductance per unit length can be easily computed as a function of frequency. We also discuss FD-TD Maxwell's equations computational modeling of lumped-circuit loads and sources in 3-D, including resistors and resistive voltage sources, capacitors, inductors, diodes, and transistors. We believe that this approach will be useful in simulating the large-signal behavior of very high-speed nonlinear analog and digital devices in the context of the full-wave time-dependent electromagnetic field.

  3. Cryocooled wideband digital channelizing radio-frequency receiver based on low-pass ADC

    International Nuclear Information System (INIS)

    Vernik, Igor V; Kirichenko, Dmitri E; Dotsenko, Vladimir V; Miller, Robert; Webber, Robert J; Shevchenko, Pavel; Talalaevskii, Andrei; Gupta, Deepnarayan; Mukhanov, Oleg A

    2007-01-01

    We have demonstrated a digital receiver performing direct digitization of radio-frequency signals over a wide frequency range from kilohertz to gigahertz. The complete system, consisting of a cryopackaged superconductor all-digital receiver (ADR) chip followed by room-temperature interface electronics and a field programmable gate array (FPGA) based post-processing module, has been developed. The ADR chip comprises a low-pass analog-to-digital converter (ADC) delta modulator with phase modulation-demodulation architecture together with digital in-phase and quadrature mixer and a pair of digital decimation filters. The chip is fabricated using a 4.5 kA cm -2 process and is cryopackaged using a commercial-off-the-shelf cryocooler. Experimental results in HF, VHF, UHF and L bands and their analysis, proving consistent operation of the cryopackaged ADR chip up to 24.32 GHz clock frequency, are presented and discussed

  4. Digital mammography: Signal-extraction strategies for computer-aided detection of microcalcifications

    International Nuclear Information System (INIS)

    Chan, H.P.; Doi, K.; Metz, C.E.; Vyborny, C.J.; Lam, K.L.; Schmidt, R.A.

    1987-01-01

    The authors found that the structured background of a mammogram can be removed effectively by either a difference-image technique (using a matched filter in combination with a median filter, a contrast-reversal filter, or a box-rim filter) or a visual response filter alone. Locally adaptive gray-level thresholding and region-growing techniques can then be employed to extract microcalcifications from the processed image. Signals are further distinguished from noise or artifacts by their size, contrast, and clustering properties. The authors studied the dependence of the detectability of microcalcifications on the various signal-extraction strategies. Potential application of the computer-aided system to mammography is assessed by its performance on clinical mammograms

  5. IIR digital filter design for powerline noise cancellation of ECG signal using arduino platform

    Science.gov (United States)

    Rahmatillah, Akif; Ataulkarim

    2017-05-01

    Powerline noise has been one of significant noises of Electrocardiogram (ECG) signal measurement. This noise is characterized by a sinusoidal signal which has 50 Hz of noise and 0.3 mV of maximum amplitude. This paper describes the design of IIR Notch filter design to reject a 50 Hz power line noise. IIR filter coefficients were calculated using pole placement method with three variations of band stop cut off frequencies of (49-51)Hz, (48 - 52)Hz, and (47 - 53)Hz. The algorithm and coefficients of filter were embedded to Arduino DUE (ARM 32 bit microcontroller). IIR notch filter designed has been able to reject power line noise with average square of error value of 0.225 on (49-51) Hz filter design and 0.2831 on (48 - 52)Hz filter design.

  6. Band extension in digital methods of transfer function determination – signal conditioners asymmetry error corrections

    Directory of Open Access Journals (Sweden)

    Zbigniew Staroszczyk

    2014-12-01

    Full Text Available [b]Abstract[/b]. In the paper, the calibrating method for error correction in transfer function determination with the use of DSP has been proposed. The correction limits/eliminates influence of transfer function input/output signal conditioners on the estimated transfer functions in the investigated object. The method exploits frequency domain conditioning paths descriptor found during training observation made on the known reference object.[b]Keywords[/b]: transfer function, band extension, error correction, phase errors

  7. High power, 140 GHz gyrotron

    International Nuclear Information System (INIS)

    Kreischer, K.E.; Temkin, R.J.; Mulligan, W.J.; MacCabe, S.; Chaplya, R.

    1982-01-01

    The design and construction of a pulsed 100 kW, 140 GHz gyrotron is described. Initial gyrotron operation is expected in early 1982. Advances in gyrotron theory have also been carried out in support of this experimental research. The application of gyrotrons to plasma diagnostics is also under investigation. (author)

  8. Optimization of a digital lock-in algorithm with a square-wave reference for frequency-divided multi-channel sensor signal detection.

    Science.gov (United States)

    Zhang, Shengzhao; Li, Gang; Lin, Ling; Zhao, Jing

    2016-08-01

    A digital lock-in detection technique is commonly used to measure the amplitude and phase of a selected frequency signal. A technique that uses a square wave as the reference signal has an advantage over the one using a sinusoidal wave due to its easier implementation and higher computational efficiency. However, demodulating multiple-frequency composite signals using square wave reference may result in interference between channels. To avoid interference between channels and reduce the computational complexity, we modify the calculations and determine the optimal parameter settings of the low-pass filter and carrier frequency, as detailed in this paper. The results of our analysis show that when the length of the average filter and carrier frequencies are properly set, the interference between the channels is removed. This optimization produces the digital lock-in detection suitable for measuring multi-channel sensor signals.

  9. The single-shot opto-digitizer; L'optoechantillonneur monocoup

    Energy Technology Data Exchange (ETDEWEB)

    Nail, M.; Gibert, Ph. [CEA/DAM-Ile de France, Dept. de Conception et Realisation des Experimentations (DCRE), 91 - Bruyeres-le-Chatel (France); CEA/DAM-Ile de France, Dept. Laser Puissance, DLP, 91 - Bruyeres-Le-Chatel (France)

    2000-07-01

    Laser-plasma experiments need to measure signals provided either by X-ray, photonic or neutronic detector. The measurement should have 50 GHz bandwidth and up to several hundred of Giga-Hertz for sub picosecond plasmas. For this purpose, a 35 GHz single shot opto-digitizer (10 ps risetime) has been studied and built. The device is made up of a 50 ohms microstrip propagation line, periodically lined by 100 sampled gates. The propagation line is long enough to measure a 400 ps duration. The sampling rate is 250 Gsa/s (every 4 ps). The sampled gates are made with fast recombining photo-material and turn on by a subpicosecond laser pulse which is synchronized exactly with the analysed phenomena. Every gate is recording to a storing capacitor. After the recording, every capacitor charge is needed to built the signal that was displayed on the propagation line. The dynamic range of measurement is 47 for the entire device. The device can measure positive or negative signals from 1.5 to 70 Volts. To increase the bandwidth, two another kinds of opto-digitizer were studied: one is a buried stripline with 56 GHz band width, the other a 70 GHz coplanar transmission line. For the purpose of subpicosecond plasmas, a 30 coplanar waveguide opto-digitizer was studied. Characteristics are as followed: window of measurement 40 ps, sampling rate 1 ps, bandwidth 230 GHz. Finally, a bundle of optical fibers was used to propagate the laser beam on semiconductor gates. If the gates are lighted at the same time, i.e. if the optical fibers have the same length, we get a simultaneous addressing. By using different lengths of optical fibers, we can do a sequential addressing. So, the sampling rate becomes a combination of the distance between two adjacent sampled channels, and the difference in length of optical fibers. (author)

  10. Implementation and test of the digital-signal-processor based components of the HERA-B data acquisition system

    International Nuclear Information System (INIS)

    Wagner, G.

    2001-02-01

    The HERA-B experiment at DESY is designed primarily to measure CP-violation in the decays of neutral B-mesons. The decay channels of interest have very low signal-to-background ratios (≤10 -10 ). Consequently, the data acquisition and triggering system must read out all 520,000 detector channels at a very high rate (10 MHz) and must suppress the background by six orders of magnitude, while selecting the interesting decays with high efficiencies. The trigger system consists of four consecutive trigger levels. A processor farm of 240 PCs is used to run the second level trigger algorithms. During event processing on a farm processor, the detector data is stored in a buffer system, which is connected to the farm via a network. The buffer system, network and the control process of the second level trigger are all implemented with SHARC digital signal processors (DSP). The task described in this thesis was the development of the DSP software. This software and the DSP hardware are described. Their functionality and availability is demonstrated based on the experience gained with the system during the 1999 and 2000 running periods. It is shown that the concept of basing the data acquisition on DSPs can be applied successfully. (orig.)

  11. A Two-Color Fourier Transform Mm-Wave Spectrometer for Gas Analysis Operating from 260-295 GHZ

    Science.gov (United States)

    Steber, Amanda L.; Harris, Brent J.; Lehmann, Kevin K.; Pate, Brooks H.

    2013-06-01

    We have designed a two-color mm-wave spectrometer for Fourier transform mm-wave spectroscopy that uses consumer level components for the tunable synthesizers, digital control of the pulse modulators, and digitization of the coherent free induction decay (FID). The excitation pulses are generated using an x24 active multiplier chain (AMC) that produces a peak power of 30 mW. The microwave input to the AMC is generated in a frequency up conversion circuit that accepts a microwave input frequency from about 2-4 GHz. This circuit also generates the input to the mm-wave subhamonic mixer that creates the local oscillator from a separate 2-4 GHz microwave input. Excitation pulses at two independently tunable frequencies are generated using a dual-channel source based on a low-cost, wideband synthesizer integrated circuit (Valon Technology Model 5008). The outputs of the synthesizer are pulse modulated using a PIN diode switch that is driven using the arbitrary waveform generator (AWG) output of a USB-controlled high-speed digitizer / arbitrary waveform generator combination unit (Tie Pie HS-5 530 XM). The two pulses are combined using a Wilkinson power divider before input to the up conversion circuit. The FID frequency is down converted in a two-stage mixing process to 65 MHz. The two LO frequencies used in the receiver are provided by a second Valon 5008. The FID is digitized at 200 MSamples/s using the 12-bit Tie Pie digitizer. The digital oscilloscope (and its AWG channel) and the two synthesizers use a 10 MHz reference signal from a Rubidium clock to permit time-domain signal averaging. A key feature of the digital oscilloscope is its deep memory of 32 Mpts (complemented by the 64 Mpt memory in the 240 MS/s AWG). This makes it possible to perform several one- and two-color coherent measurements, including pulse echoes and double-resonance spectroscopy, in a single "readout" experiment to speed the analysis of mm-wave rotational spectra. The spectrometer sensitivity

  12. Shift register performance at 4 GHz

    International Nuclear Information System (INIS)

    Przybysz, J.X.; Meier, D.L.; Kang, J.

    1991-01-01

    This paper reports on two mask layouts designed to give Josephson shift register operation above 2 GHz. Custom instrumentation was assembled for tests up to 4 GHz. Shift registers using coplanar waveguide structures for on-chip power distribution operated properly up to 3.3 GHz. Better performance was obtained when power was distributed through microstrip transmission lines. At the tester limit of 4 GHz, microstrip circuits operated properly with bias margin of ±15%

  13. Feedback correction of injection errors using digital signal-processing techniques

    Directory of Open Access Journals (Sweden)

    N. S. Sereno

    2007-01-01

    Full Text Available Efficient transfer of electron beams from one accelerator to another is important for 3rd-generation light sources that operate using top-up. In top-up mode, a constant amount of charge is injected at regular intervals into the storage ring to replenish beam lost primarily due to Touschek scattering. Top-up therefore requires that the complex of injector accelerators that fill the storage ring transport beam with a minimum amount of loss. Injection can be a source of significant beam loss if not carefully controlled. In this note we describe a method of processing injection transient signals produced by beam-position monitors and using the processed data in feedback. Feedback control using the technique described here has been incorporated in the Advanced Photon Source (APS booster synchrotron to correct injection transients.

  14. An efficient digital signal processing method for RRNS-based DS-CDMA systems

    Directory of Open Access Journals (Sweden)

    Peter Olsovsky

    2017-09-01

    Full Text Available This paper deals with an efficient method for achieving low power and high speed in advanced Direct-Sequence Code Division Multiple-Access (DS-CDMA wireless communication systems based on the Residue Number System (RNS. A modified algorithm for multiuser DS-CDMA signal generation in MATLAB is proposed and investigated. The most important characteristics of the generated PN code are also presented. Subsequently, a DS-CDMA system based on the combination of the RNS or the so-called Redundant Residue Number System (RRNS is proposed. The enhanced method using a spectrally efficient 8-PSK data modulation scheme to improve the bandwidth efficiency for RRNS-based DS-CDMA systems is presented. By using the C-measure (complexity measure of the error detection function, it is possible to estimate the size of the circuit. Error detection function in RRNSs can be efficiently implemented by LookUp Table (LUT cascades.

  15. Digital Signal Processing. A review of DSP formalism, algorithms and networks for the beam instrumentation workshop, Vancouver, Canada, October 4, 1994

    International Nuclear Information System (INIS)

    Linscott, I.

    1995-01-01

    The formalism of Digital Signal Processing (DSP), is reviewed with the objective of providing a framework for understanding the utility of DSP techniques for Beam Instrumentation and developiong criteria for assessing the merits of DSP applications. copyright 1995 American Institute of Physics

  16. Digital rotational microphotometer of the module conception with optical separation of control signals for measurement of granularity of the colour photographic films

    Czech Academy of Sciences Publication Activity Database

    Hrdý, J.; Pospíšil, Jaroslav

    2003-01-01

    Roč. 114, č. 6 (2003), s. 279-288 ISSN 0030-4026 Institutional research plan: CEZ:AV0Z1010921 Keywords : colour photographic granularity * digital rotational microphotometrical granulometer * low- speed scaning * modul conception of microphotometer * optical separation of control signals Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.534, year: 2003

  17. High sensitivity broadband 360GHz passive receiver for TeraSCREEN

    Science.gov (United States)

    Wang, Hui; Oldfield, Matthew; Maestrojuán, Itziar; Platt, Duncan; Brewster, Nick; Viegas, Colin; Alderman, Byron; Ellison, Brian N.

    2016-05-01

    TeraSCREEN is an EU FP7 Security project aimed at developing a combined active, with frequency channel centered at 360 GHz, and passive, with frequency channels centered at 94, 220 and 360 GHz, imaging system for border controls in airport and commercial ferry ports. The system will include automatic threat detection and classification and has been designed with a strong focus on the ethical, legal and practical aspects of operating in these environments and with the potential threats in mind. Furthermore, both the passive and active systems are based on array receivers with the active system consisting of a 16 element MIMO FMCW radar centered at 360 GHz with a bandwidth of 30 GHz utilizing a custom made direct digital synthesizer. The 16 element passive receiver system at 360 GHz uses commercial Gunn diode oscillators at 90 GHz followed by custom made 90 to 180 GHz frequency doublers supplying the local oscillator for 360 GHz sub-harmonic mixers. This paper describes the development of the passive antenna module, local oscillator chain, frequency mixers and detectors used in the passive receiver array of this system. The complete passive receiver chain is characterized in this paper.

  18. Single channel 112Gbit/sec PAM4 at 56Gbaud with digital signal processing for data centers applications.

    Science.gov (United States)

    Sadot, Dan; Dorman, G; Gorshtein, Albert; Sonkin, Eduard; Vidal, Or

    2015-01-26

    112Gbit/sec DSP-based single channel transmission of PAM4 at 56Gbaud over 15GHz of effective analog bandwidth is experimentally demonstrated. The DSP enables use of mature 25G optoelectronics for 2-10km datacenter intra-connections, and 8Tbit/sec over 80km interconnections between data centers.

  19. Ihh and PTH1R signaling in limb mesenchyme is required for proper segmentation and subsequent formation and growth of digit bones.

    Science.gov (United States)

    Amano, Katsuhiko; Densmore, Michael; Fan, Yi; Lanske, Beate

    2016-02-01

    Digit formation is a process, which requires the proper segmentation, formation and growth of phalangeal bones and is precisely regulated by several important factors. One such factor is Ihh, a gene linked to BDA1 and distal symphalangism in humans. In existing mouse models, mutations in Ihh have been shown to cause multiple synostosis in the digits but lead to perinatal lethality. To better study the exact biological and pathological events which occur in these fused digits, we used a more viable Prx1-Cre;Ihh(fl/fl) model in which Cre recombinase is expressed during mesenchymal condensation in the earliest limb buds at E9.5 dpc and found that mutant digits continuously fuse postnatally until phalanges are finally replaced by an unsegmented "one-stick bone". Mutant mice displayed osteocalcin-positive mature osteoblasts, but had reduced proliferation and abnormal osteogenesis. Because of the close interaction between Ihh and PTHrP during endochondral ossification, we also examined the digits of Prx1-Cre;PTH1R(fl/fl) mice, where the receptor for PTHrP was conditionally deleted. Surprisingly, we found PTH1R deletion caused symphalangism, demonstrating another novel function of PTH1R signaling in digit formation. We characterized the symphalangism process whereby initial cartilaginous fusion prevented epiphyseal growth plate formation, resulting in resorption and replacement of the remaining cartilage by bony tissue. Chondrocyte differentiation displayed abnormal directionality in both mutants. Lastly, Prx1-Cre;Ihh(fl/fl);Jansen Tg mice, in which a constitutively active PTH1R allele was introduced into Ihh mutants, were established to address the possible involvement of PTH1R signaling in Ihh mutant digits. These rescue mice failed to show significantly improved phenotype, suggesting that PTH1R signaling in chondrocytes is not sufficient to restore digit formation. Our results demonstrate that Ihh and PTH1R signaling in limb mesenchyme are both essential to regulate

  20. Development of the Phase-up Technology of the Radio Telescopes: 6.7 GHz Methanol Maser Observations with Phased Hitachi 32 m and Takahagi 32 m Radio Telescopes

    Science.gov (United States)

    Takefuji, K.; Sugiyama, K.; Yonekura, Y.; Saito, T.; Fujisawa, K.; Kondo, T.

    2017-11-01

    For the sake of high-sensitivity 6.7 GHz methanol maser observations, we developed a new technology for coherently combining the two signals from the Hitachi 32 m radio telescope and the Takahagi 32 m radio telescope of the Japanese Very long baseline interferometer Network (JVN), where the two telescopes were separated by about 260 m. After the two telescopes were phased as a twofold larger single telescope, the mean signal-to-noise ratio (S/N) of the 6.7 GHz methanol masers observed by the phased telescopes was improved to 1.254-fold higher than that of the single dish, through a very long baseline interferometry (VLBI) experiment on the 50 km baseline of the Kashima 34 m telescope and the 1000 km baseline of the Yamaguchi 32 m telescope. Furthermore, we compared the S/Ns of the 6.7 GHz maser spectra for two methods. One is a VLBI method and the other is the newly developed digital position switching that is a similar technology to that used in noise-canceling headphones. Finally, we confirmed that the mean S/N of method of the digital position switching (ON-OFF) was 1.597-fold higher than that of the VLBI method.

  1. Digital Beam Position Monitor for the Happex Experiment

    Energy Technology Data Exchange (ETDEWEB)

    S.R. Kauffman; H. Dong; A. Freyberger; L. Kaufman; J. Musson

    2005-05-16

    The proposed HAPPEX experiment at CEBAF employs a three cavity monitor system for high-precision (1 mm), high-bandwidth (100 kHz) position measurements. This is performed using a cavity triplet consisting of two TM110-mode cavities (one each for X and Y planes) combined with a conventional TM-010-mode cavity for a phase and magnitude reference. Traditional systems have used the TM010 cavity output to directly down convert the BPM cavity signals to base band. The Multi-channel HAPPEX digital receiver simultaneously I/Q samples each cavity and extracts position using a CORDIC algorithm. The hardware design consists of a digital receiver daughter board and digital processor motherboard that resides in a VXI crate. The daughter board down converts 1.497 GHz signals from the TM010 cavity and X and Y signals from the TM110 cavities to 4 MHz, and extracts the quadrature digital signals. The motherboard processes this data and computes beam intensity and X-Y positions with a resolution of one mm, 100 kHz output bandwidth, and overall latency of ten microseconds. The results are available in both analog and digital format.

  2. Influence of scatter reduction on lesion signal-to-noise ratio and lesion detection in digital chest radiography

    Science.gov (United States)

    Neitzel, Ulrich; Pralow, Thomas; Schaefer-Prokop, Cornelia M.; Prokop, Mathias

    1998-07-01

    This study was performed to investigate the effect of an additional antiscatter grid on the detail signal-to-noise ratio (SNR) and the visual detail detectability with a digital chest radiography system. An anthropomorphic chest phantom with different types of superimposed lesions was used to obtain four series of images simulating slim and thick patients, both with and without an additional grid. The exposure to the phantom was identical for the grid and non- grid situations. Difference images were then produced by subtracting an 'empty' thorax image (without superimposed lesions) from each image of the series. The difference images were used to measure detail contrast and detail SNR in different areas of the chest. Although the grid generally improved the lesion contrast, an improvement in lesion SNR was only obtained for some lesions in the obscured regions. In the lung area the lesion SNR was lower with the grid. ROC analysis showed only minor differences between grid and non-grid images in the visual detectability of the lesions; detectability was significantly higher, however, in the difference images compared to the original chest images. The results indicate that the use of the additional antiscatter grid is not necessary if the image contrast is restored by suitable image processing. Methods which reduce or eliminate the overlying anatomical structures in chest images lead to a significantly higher lesion detectability.

  3. Channel Characteristics and User Body Effects in an Outdoor Urban Scenario at 15 and 28 GHz

    DEFF Research Database (Denmark)

    Zhao, Kun; Gustafson, Carl; Liao, Qingbi

    2017-01-01

    The effect of a user’s body on channel characteristics for single user downlink transmission in an urban scenario for the 5th generation (5G) systems is investigated with ray-tracing at 15 GHz and 28 GHz. Three different designs of user equipment (UE) antennas are fabricated and integrated...... into a mobile phone prototype, and their 3D radiation patterns are measured both with and without a user. The user remains in Cellular Telephone Industries Association (CTIA) standard data mode and talking mode during measurements. The results show that the user’s body will cause a strong shadowing loss...... and generate a large fluctuation on the received signal strength of the UE at both 15 GHz and 28 GHz, which is crucial to channel modeling studies at frequencies above 6 GHz. In addition, the user’s body effect on a linear array system in UE is presented, and the main challenges for the future work are also...

  4. Digital non-linear equalization for flexible capacity ultradense WDM channels for metro core networking

    DEFF Research Database (Denmark)

    Arlunno, Valeria; Zhang, Xu; Larsen, Knud J.

    2011-01-01

    An experimental demonstration of Ultradense WDM with advanced digital signal processing is presented. The scheme proposed allows the use of independent tunable DFB lasers spaced at 12.5 GHz for ultradense WDM PM-QPSK flexible capacity channels for metro core networking. To allocate extremely closed...... carriers, we demonstrate that a digital non-linear equalization allow to mitigate inter-channel interference and improve overall system performance in terms of OSNR. Evaluation of the algorithm and comparison with an ultradense WDM system with coherent carriers generated from a single laser are also...

  5. Digital non-linear equalization for flexible capacity ultradense WDM channels for metro core networking.

    Science.gov (United States)

    Arlunno, Valeria; Zhang, Xu; Larsen, Knud J; Zibar, Darko; Monroy, Idelfonso Tafur

    2011-12-12

    An experimental demonstration of Ultradense WDM with advanced digital signal processing is presented. The scheme proposed allows the use of independent tunable DFB lasers spaced at 12.5 GHz for ultradense WDM PM-QPSK flexible capacity channels for metro core networking. To allocate extremely closed carriers, we demonstrate that a digital non-linear equalization allow to mitigate inter-channel interference and improve overall system performance in terms of OSNR. Evaluation of the algorithm and comparison with an ultradense WDM system with coherent carriers generated from a single laser are also reported. © 2011 Optical Society of America

  6. Performance Analysis of OFDM 60GHz System and SC-FDE 60GHz System

    Directory of Open Access Journals (Sweden)

    Han Xueyan

    2016-01-01

    Full Text Available In this paper, the performance of 60GHz wireless communication system with SC and OFDM is studied, the models of OFDM 60GHz system and SC 60GHz frequency domain equalization (SC-FDE system are established, and the bit error rate (BER performance of OFDM 60GHz system and SC-FDE 60GHz system in 802.15.3c channels is compared. The simulation results show that SC-FDE 60GHz system has a slight advantage over OFDM system in line-of-sight (LOS channels, while OFDM 60GHz system has a slight advantage over SC-FDE system in non-line-of-sight (NLOS channels. For 60GHz system, OFDM 60GHz system has a slight advantage over SC-FDE system in overcoming multipath fading, but the performance of both is close whether in the LOS or NLOS case.

  7. MMIC DHBT Common-Base Amplifier for 172 GHz

    Science.gov (United States)

    Paidi, Vamsi; Griffith, Zack; Wei, Yun; Dahlstrom, Mttias; Urteaga, Miguel; Rodwell, Mark; Samoska, Lorene; Fung, King Man; Schlecht, Erich

    2006-01-01

    Figure 1 shows a single-stage monolithic microwave integrated circuit (MMIC) power amplifier in which the gain element is a double-heterojunction bipolar transistor (DHBT) connected in common-base configuration. This amplifier, which has been demonstrated to function well at a frequency of 172 GHz, is part of a continuing effort to develop compact, efficient amplifiers for scientific instrumentation, wide-band communication systems, and radar systems that will operate at frequencies up to and beyond 180 GHz. The transistor is fabricated from a layered structure formed by molecular beam epitaxy in the InP/InGaAs material system. A highly doped InGaAs base layer and a collector layer are fabricated from the layered structure in a triple mesa process. The transistor includes two separate emitter fingers, each having dimensions of 0.8 by 12 m. The common-base configuration was chosen for its high maximum stable gain in the frequency band of interest. The input-matching network is designed for high bandwidth. The output of the transistor is matched to a load line for maximum saturated output power under large-signal conditions, rather than being matched for maximum gain under small-signal conditions. In a test at a frequency of 172 GHz, the amplifier was found to generate an output power of 7.5 mW, with approximately 5 dB of large-signal gain (see Figure 2). Moreover, the amplifier exhibited a peak small-signal gain of 7 dB at a frequency of 176 GHz. This performance of this MMIC single-stage amplifier containing only a single transistor represents a significant advance in the state of the art, in that it rivals the 170-GHz performance of a prior MMIC three-stage, four-transistor amplifier. [The prior amplifier was reported in "MMIC HEMT Power Amplifier for 140 to 170 GHz" (NPO-30127), NASA Tech Briefs, Vol. 27, No. 11 (November 2003), page 49.] This amplifier is the first heterojunction- bipolar-transistor (HBT) amplifier built for medium power operation in this

  8. First harmonic injection locking of 24-GHz-oscillators

    Directory of Open Access Journals (Sweden)

    M. R. Kühn

    2003-01-01

    Full Text Available An increasing number of applications is proposed for the 24 GHz ISM-band, like automotive radar systems and short-range communication links. These applications demand for oscillators providing moderate output power of a few mW and moderate frequency stability of about 0.5%. The maximum oscillation frequency of low-cost off-theshelf transistors is too low for stable operation of a fundamental 24GHz oscillator. Thus, we designed a 24 GHz first harmonic oscillator, where the power generated at the fundamental frequency (12 GHz is reflected resulting in effective generation of output power at the first harmonic. We measured a radiated power from an integrated planar antenna of more than 1mW. Though this oscillator provides superior frequency stability compared to fundamental oscillators, for some applications additional stabilization is required. As a low-cost measure, injection locking can be used to phase lock oscillators that provide sufficient stability in free running mode. Due to our harmonic oscillator concept injection locking has to be achieved at the first harmonic, since only the antenna is accessible for signal injection. We designed, fabricated and characterized a harmonic oscillator using the antenna as a port for injection locking. The locking range was measured versus various parameters. In addition, phase-noise improvement was investigated. A theoretical approach for the mechanism of first harmonic injection locking is presented.

  9. 45-Gbps 3D-CAP transmission over a 16-GHz bandwidth SSMF link assisted by Wiener filtering

    Science.gov (United States)

    Sun, Lin; Du, Jiangbing; You, Yue; Liang, Chenyu; Zhang, Wenjia; Ma, Lin; He, Zuyuan

    2017-04-01

    In this study, the optical 3-dimensional carrier-less amplitude phase (3D-CAP) modulation up to 45 Gbps at 1550 nm is demonstrated and standard single mode fiber (SSMF) transmission up to 10-Km is achieved. The 10-dB bandwidth of the optical back-to-back link is only 16 GHz. Digital Wiener filter is employed to compensate signal distortion with low algorithm complexity. The results indicate a power sensitivity of about 2-dBm after 10-Km transmission for achieving BER of 3.8e-3 at 7% FEC limit. To our best acknowledgement, this is the highest transmission capacity for the 3D-CAP transmission over 10-Km SSMF at 1550 nm. The demonstrated results of 3D-CAP modulation and transmission with paralleled data streams in 3 dimensions present a good potential for improving the density and reducing the cost of parallel optical transceivers in short reach optical interconnections.

  10. Protein kinase D2 is a digital amplifier of T cell receptor-stimulated diacylglycerol signaling in naïve CD8⁺ T cells.

    Science.gov (United States)

    Navarro, María N; Feijoo-Carnero, Carmen; Arandilla, Alba Gonzalez; Trost, Matthias; Cantrell, Doreen A

    2014-10-21

    Protein kinase D2 (PKD2) is a serine and threonine kinase that is activated in T cells by diacylglycerol and protein kinase C in response to stimulation of the T cell receptor (TCR) by antigen. We quantified the activation of PKD2 at the single-cell level and found that this kinase acts as a sensitive digital amplifier of TCR engagement, enabling CD8(+) T cells to match the production of inflammatory cytokines to the quality and quantity of TCR ligands. There was a digital response pattern of PKD2 activation in response to TCR engagement, such that increasing the concentration and potency of TCR ligands increased the number of cells that exhibited activated PKD2. However, for each cell that responded to TCR stimulation, the entire cellular pool of PKD2 (~400,000 molecules) was activated. Moreover, PKD2 acted as an amplification checkpoint for antigen-stimulated digital cytokine responses and translated the differential strength of TCR signaling to determine the number of naïve CD8(+) T cells that became effector cells. Together, these results provide insights into PKD family kinases and how they act digitally to amplify signaling networks controlled by the TCR.

  11. Digital implementation of a laser frequency stabilisation technique in the telecommunications band

    Science.gov (United States)

    Jivan, Pritesh; van Brakel, Adriaan; Manuel, Rodolfo Martínez; Grobler, Michael

    2016-02-01

    Laser frequency stabilisation in the telecommunications band was realised using the Pound-Drever-Hall (PDH) error signal. The transmission spectrum of the Fabry-Perot cavity was used as opposed to the traditionally used reflected spectrum. A comparison was done using an analogue as well as a digitally implemented system. This study forms part of an initial step towards developing a portable optical time and frequency standard. The frequency discriminator used in the experimental setup was a fibre-based Fabry-Perot etalon. The phase sensitive system made use of the optical heterodyne technique to detect changes in the phase of the system. A lock-in amplifier was used to filter and mix the input signals to generate the error signal. This error signal may then be used to generate a control signal via a PID controller. An error signal was realised at a wavelength of 1556 nm which correlates to an optical frequency of 1.926 THz. An implementation of the analogue PDH technique yielded an error signal with a bandwidth of 6.134 GHz, while a digital implementation yielded a bandwidth of 5.774 GHz.

  12. 42.13 gbit/s 16qam-OFDM photonics-wireless transmission in 75-110 GHz band

    DEFF Research Database (Denmark)

    Deng, Lei; Liu, D. M.; Pang, Xiaodan

    2012-01-01

    We present a simple architecture for realizing high capacity W-band (75-110 GHz) photonics-wireless system. 42.13 Gbit/s 16QAM-OFDM optical baseband signal is obtained in a seamless 15 GHz spectral bandwidth by using an optical frequency comb generator, resulting in a spectral efficiency of 2.808...

  13. Digital Signal Processors

    Indian Academy of Sciences (India)

    days in a variety of consumer products such as cellular phones, modems, audio systems and video game terminals, to cite a few. Their use is growing with the rising demand for high quality consumer products which process information in real-time. As they are widely used in cost sensitive consumer products their cost is a ...

  14. Flat pulse-amplitude rational-harmonic-mode-locking fiber lasers with GHz pulse repetition rates

    Science.gov (United States)

    Wang, Tianhe; Yang, Tianxin; Jia, Dongfang; Wang, Zhaoying; Sang, Mei; Bai, Neng; Li, Guifang

    2013-03-01

    Rational harmonic mode locking (RHML) in an active mode-locked fiber laser can increase the output pulse repetition rate a number of times the modulation frequency of an optical modulator in a cavity when driven by gigahertz (GHz) RF. The amplitudes of the output optical pulse train in a high order RHML operation are not equalized and flat due to the GHz RF drive signals. A modified RHML technique using standard instrumentation that generates 1 GHz electrical square wave signals to accomplish up to 6th order RHML in fiber lasers is presented for improving the flatness of the amplitudes of the output optical pulse train at the pulse repetition rate of up to 12 GHz.

  15. Study of converged 60 GHz radio over fiber with WDM-PON access networks

    OpenAIRE

    Shao, Tong

    2012-01-01

    Recently, convergence of 60 GHz radio over fiber (RoF) technique with wavelength division multiplexing (WDM) passive optical networks (PON) has raised great interests because it provides the possibility for simultaneous broadband 60 GHz signal generation and multi-gigabit per second wireline transmission. The objective of the thesis is to study the solutions for converged 60 GHz RoF and WDM-PON technique.In this thesis, we have made the following achievements for RoF technology and the integr...

  16. Continuously Tunable 250 GHz Gyrotron with a Double Disk Window for DNP-NMR Spectroscopy.

    Science.gov (United States)

    Jawla, Sudheer; Ni, Qing Zhe; Barnes, Alexander; Guss, William; Daviso, Eugenio; Herzfeld, Judith; Griffin, Robert; Temkin, Richard

    2013-01-01

    In this paper, we describe the design and experimental results from the rebuild of a 250 GHz gyrotron used for Dynamic Nuclear Polarization enhanced Nuclear Magnetic Resonance spectroscopy on a 380 MHz spectrometer. Tuning bandwidth of approximately 2 GHz is easily achieved at a fixed magnetic field of 9.24 T and a beam current of 95 mA producing an average output power of >10 W over the entire tuning band. This tube incorporates a double disk output sapphire window in order to maximize the transmission at 250.58 GHz. DNP Signal enhancement of >125 is achieved on a 13 C-Urea sample using this gyrotron.

  17. The design and evaluation of a 5.8 ghz laptop-based radar system

    Science.gov (United States)

    Teng, Kevin Chi-Ming

    This project involves design and analysis of a 5.8 GHz laptop-based radar system. The radar system measures Doppler, ranging and forming Synthetic Aperture Radar (SAR) images utilizing Matlab software provided from MIT Open Courseware and performs data acquisition and signal processing. The main purpose of this work is to bring new perspective to the existing radar project by increasing the ISM band frequency from 2.4 GHz to 5.8 GHz and to carry out a series of experiments on the implementation of the radar kit. Demonstrating the radar at higher operating frequency is capable of providing accurate data results in Doppler, ranging and SAR images.

  18. The Design and Evaluation of a 5.8 GHz Laptop-Based Radar System

    OpenAIRE

    Teng, Kevin Chi-Ming

    2013-01-01

    This project involves design and analysis of a 5.8 GHz laptop-based radar system. The radar system measures Doppler, ranging and forming Synthetic Aperture Radar (SAR) images utilizing Matlab software provided from MIT Open Courseware and performs data acquisition and signal processing. The main purpose of this work is to bring new perspective to the existing radar project by increasing the ISM band frequency from 2.4 GHz to 5.8 GHz and to carry out a series of experiments on the implementati...

  19. Signal Processing and Restoration

    NARCIS (Netherlands)

    Biemond, J.; Slump, C.H.; Lagendijk, R.L.; Tolhuizen, L.M.G.M.; de With, P.H.N.

    2004-01-01

    Digital Signal Processing (DSP) concerns the theoretical and practical aspects of representing information-bearing signals in digital form and the use of processors or special purpose hardware to extract that information or to transform the signals in useful ways. Areas where digital signal

  20. Hall Thruster Impact Analysis on Digital Satellite Communications

    Science.gov (United States)

    Zuniga, C. D.; Hallock, G. A.; Wiley, J. C.; Meyer, J. W.; Loane, J. T.

    2002-11-01

    Hall Thrusters will be used for stationkeeping of geosynchronous communications satellites. These thrusters produce an inhomogeneous plasma plume which may interfere with communications signals (1-20 GHz) to and from the satellite. The plume's effects include beam-pointing error, beam attenuation, and spectral modulation [1]. Many systems digitally modulate an RF carrier and use coherent detection methods. The plasma may degrade the performance of these systems by diminishing the SNR at the receiver by squinting the beam away and degrading the synchronization by phase modulating the signal. We simulate a receiver whose input signals have been corrupted by the plasma plume. These modified input signals are formed by using the results of a previously developed ray tracing code [1]. We will present performance measures including bit-error rates and link availability. * Work supported by Lockheed Martin Corp. and the Texas Higher Education Coordinating Board. [1] Hallock et al, J. Spacecraft and Rockets V. 39 No 1 pp 115-124

  1. Low conversion loss 94 GHz and 188 GHz doublers in InP DHBT technology

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Johansen, Tom Keinicke; Squartecchia, Michele

    2017-01-01

    An Indium Phosphide (InP) Double Heterojunction Bipolar Transistor (DHBT) process has been utilized to design two doublers to cover the 94 GHz and 188 GHz bands. The 94 GHz doubler employs 4-finger DHBTs and provides conversion loss of 2 dB. A maximum output power of nearly 3 dBm is measured while...

  2. Digital beam position monitor for the HAPPEX experiment

    Energy Technology Data Exchange (ETDEWEB)

    Sherlon Kauffman; John Musson; Hai Dong; Lisa Kaufman; Arne Freyberger

    2005-05-01

    The proposed HAPPEX experiment at CEBAF employs a three cavity monitor system for high precision (1um), high bandwidth (100 kHz) position measurements. This is performed using a cavity triplet consisting of two TM110-mode cavities (one each for X and Y planes) combined with a conventional TM010-mode cavity for a phase and magnitude reference. Traditional systems have used the TM010 cavity output to directly down convert the BPM cavity signals to base band. The multi-channel HAPPEX digital receiver simultaneously I/Q samples each cavity and extracts position using a CORDIC algorithm. The hardware design consists of a RF receiver daughter board and a digital processor motherboard that resides in a VXI crate. The daughter board down converts 1.497 GHz signals from the TM010 cavity and X and Y signals from the TM110 cavities to 3 MHz and extracts the quadrature digital signals. The motherboard processes this data and computes beam intensity and X-Y positions with resolution of 1um, 100 kHz output bandwidth, and overall latency of 1us. The results are available in both the analog and digital format.

  3. Feasibility Study and Experimental Verification of Simplified Fiber-Supported 60-GHz Picocell Mobile Backhaul Links

    DEFF Research Database (Denmark)

    Lebedev, Alexander; Pang, Xiaodan; Vegas Olmos, Juan José

    2013-01-01

    We propose and experimentally demonstrate a fiber-wireless transmission system for optimized delivery of 60-GHz radio frequency (RF) signals through picocell mobile backhaul connections. We identify advantages of 60-GHz links for utilization in short-range mobile backhaul through feasibility...... of fiber transmission. The system is simplified and tailored for delivery of on-off keying data signals by employing a single module for lightwave generation and modulation combined with a simplified RF downconversion technique by envelope detection. Data signals of 1.25 Gb/s are transmitted, and a bit...

  4. Digital filters

    CERN Document Server

    Hamming, Richard W

    1997-01-01

    Digital signals occur in an increasing number of applications: in telephone communications; in radio, television, and stereo sound systems; and in spacecraft transmissions, to name just a few. This introductory text examines digital filtering, the processes of smoothing, predicting, differentiating, integrating, and separating signals, as well as the removal of noise from a signal. The processes bear particular relevance to computer applications, one of the focuses of this book.Readers will find Hamming's analysis accessible and engaging, in recognition of the fact that many people with the s

  5. Heterodyne laser-Doppler vibrometer with a slow-shear-mode Bragg cell for vibration measurements up to 1.2 GHz

    Science.gov (United States)

    Rembe, Christian; Boedecker, Sebastian; Dräbenstedt, Alexander; Pudewills, Fred; Siegmund, Georg

    2008-06-01

    Several new applications for optical ultra-high frequency (UHF) measurements have been evolved during the last decade by advancements in ultra-sonic filters and actuators as well as by the progress in micro- and nanotechnology. These new applications require new testing methods. Laser-based, non-influencing optical testing is the best choice. In this paper we present a laser-Doppler vibrometer for vibration measurements at frequencies up to 1.2 GHz. The frequency-shifter in the heterodyne interferometer is a slow-shear-mode Bragg cell. The light source in the interferometer is a green DPSS (diode pumped solid state) laser. At this wavelength the highest possible frequency shift between zero and first diffraction order is a few MHz above 300 MHz for a slow shear-mode Bragg cell and, therefore, the highest possible bandwidth of the laser-Doppler vibrometer should usually be around 300 MHz. A new optical arrangement and a novel signal processing of the digitized photo-detector signal is employed to expand the bandwidth to 1.2 GHz. We describe the utilized techniques and present the characterization of the new ultra-high-frequency (UHF) vibrometer. An example measurement on a surface acoustic wave (SAW) resonator oscillating at 262 MHz is also demonstrated. The light-power of the measurement beam can be switched on rapidly by a trigger signal to avoid thermal influences on the sample.

  6. The MALT 90 GHz Pilot Survey

    Science.gov (United States)

    Jackson, James; Rathborne, Jill; Muller, Erik; Cunningham, Maria; Brooks, Kate; Fuller, Gary; Barnes, Peter; Ellingsen, Simon; Longmore, Steven; Wyrowski, Friedrich; Walsh, Andrew; Peretto, Nicolas

    2009-04-01

    In early November, 2008, Australian and international Galactic astronomers met to plan future surveys of the Galactic plane with ATNF facilities. We intend to coordinate our efforts so that such surveys produce the maximum scientific return with minimal overlap in observations. To this end, the Millimetre Astronomers Large-area multi-Transition (MALT) team was formed. The MALT team has identified key Galactic plane surveys: a 42--50 GHz survey, a 90 GHz survey and a 115 GHz survey. In this proposal, we aim to conduct a pilot survey to explore options in the 90 GHz (3 mm) range. This pilot survey will provide detection rates, typical line strengths, and source sizes for various "finder charts" for high-mass star-forming cores. Such information is crucial for a rational design of a complete 90 GHz MALT survey.

  7. Home Networking at 60 GHz

    NARCIS (Netherlands)

    Genç, Z.

    2014-01-01

    The revolution of Information Technology in our lives has started by changing the way we work and continued with the way we entertain, communicate, interact, learn and so on. The wave of digital change has long been at the doorstep of the home to revolutionize our living experience. The initial

  8. Geolocation of RF signals

    CERN Document Server

    Progri, Ilir

    2011-01-01

    ""Geolocation of RF Signals - Principles and Simulations"" offers an overview of the best practices and innovative techniques in the art and science of geolocation over the last twenty years. It covers all research and development aspects including theoretical analysis, RF signals, geolocation techniques, key block diagrams, and practical principle simulation examples in the frequency band from 100 MHz to 18 GHz or even 60 GHz. Starting with RF signals, the book progressively examines various signal bands - such as VLF, LF, MF, HF, VHF, UHF, L, S, C, X, Ku, and, K and the corresponding geoloca

  9. A rigorous analysis of digital pre-emphasis and DAC resolution for interleaved DAC Nyquist-WDM signal generation in high-speed coherent optical transmission systems

    Science.gov (United States)

    Weng, Yi; Wang, Junyi; He, Xuan; Pan, Zhongqi

    2018-02-01

    The Nyquist spectral shaping techniques facilitate a promising solution to enhance spectral efficiency (SE) and further reduce the cost-per-bit in high-speed wavelength-division multiplexing (WDM) transmission systems. Hypothetically, any Nyquist WDM signals with arbitrary shapes can be generated by the use of the digital signal processing (DSP) based electrical filters (E-filter). Nonetheless, in actual 100G/ 200G coherent systems, the performance as well as DSP complexity are increasingly restricted by cost and power consumption. Henceforward it is indispensable to optimize DSP to accomplish the preferred performance at the least complexity. In this paper, we systematically investigated the minimum requirements and challenges of Nyquist WDM signal generation, particularly for higher-order modulation formats, including 16 quadrature amplitude modulation (QAM) or 64QAM. A variety of interrelated parameters, such as channel spacing and roll-off factor, have been evaluated to optimize the requirements of the digital-to-analog converter (DAC) resolution and transmitter E-filter bandwidth. The impact of spectral pre-emphasis has been predominantly enhanced via the proposed interleaved DAC architecture by at least 4%, and hence reducing the required optical signal to noise ratio (OSNR) at a bit error rate (BER) of 10-3 by over 0.45 dB at a channel spacing of 1.05 symbol rate and an optimized roll-off factor of 0.1. Furthermore, the requirements of sampling rate for different types of super-Gaussian E-filters are discussed for 64QAM Nyquist WDM transmission systems. Finally, the impact of the non-50% duty cycle error between sub-DACs upon the quality of the generated signals for the interleaved DAC structure has been analyzed.

  10. 60-GHz CMOS phase-locked loops

    CERN Document Server

    Cheema, Hammad M; van Roermund, Arthur HM

    2010-01-01

    The promising high data rate wireless applications at millimeter wave frequencies in general and 60 GHz in particular have gained much attention in recent years. However, challenges related to circuit, layout and measurements during mm-wave CMOS IC design have to be overcome before they can become viable for mass market. ""60-GHz CMOS Phase-Locked Loops"" focusing on phase-locked loops for 60 GHz wireless transceivers elaborates these challenges and proposes solutions for them. The system level design to circuit level implementation of the complete PLL, along with separate implementations of i

  11. Towards Graphene GHz/THz Nanosensor

    Science.gov (United States)

    Mahjoub, Akram M.; Motooka, Shoutaro; Aoki, Nobuyuki; Song, Jungwoo; Bird, Jonathan P.; Kawano, Yukio; Ferry, David K.; Ishibashi, Koji; Ochiai, Yuichi

    2011-07-01

    A quantum dot (QD) sensing device, fabricated from nanoscaled carbon material has been studied using of a bilayer graphene field effect transistor in order to enable its application to the detection of microwave (GHz) and/or terahertz (THz) radiation. Recently, it has been found that there exist several common features in low temperature quantum transport, found in experimental results of conductance quantization in a semiconductor QDs and the magnetoresistance of a graphene QDs. The applicability of a graphene field effect transistor at the GHz/THz range is discussed in terms of the microwave transconductance characteristics up to 40 GHz.

  12. An RF Power Amplifier in a Digital CMOS Process

    DEFF Research Database (Denmark)

    Nielsen, Per Asbeck; Fallesen, Carsten

    2002-01-01

    A two stage class B power amplifier for 1.9 GHz is presented. The amplifier is fabricated in a standard digital EPI-CMOS process with low resistivity substrate. The measured output power is 29 dBm in a 50 Omega load. A design method to find the large signal parameters of the output transistor...... is presented. It separates the determination of the optimal load resistance and the determination of the large signal drain-source capacitance. Based on this method, proper values for on-chip interstage matching and off-chip output matching can be derived. A envelope linearisation circuit for the PA...... is proposed. Simulations and measurements of a fabricated linearisation circuit are presented and used to calculate the achievable linearity in terms of the spectral leakage and the error vector magnitude of a EDGE (3 pi /8-8PSK) modulated signal....

  13. Carbon Nanotubes-Based Digitally Programmable Current Follower

    Directory of Open Access Journals (Sweden)

    S. K. Tripathi

    2018-01-01

    Full Text Available The physical constraints of ever-shrinking CMOS transistors are rapidly approaching atomistic and quantum mechanical limits. Therefore, research is now directed towards the development of nanoscale devices that could work efficiently in the sub-10 nm regime. This coupled with the fact that recent design trend for analog signal processing applications is moving towards current-mode circuits which offer lower voltage swings, higher bandwidth, and better signal linearity is the motivation for this work. A digitally controlled DVCC has been realized using CNFETs. This work exploited the CNFET’s parameters like chirality, pitch, and numbers of CNTs to perform the digital control operation. The circuit has minimum number of transistors and can control the output current digitally. A similar CMOS circuit with 32 nm CMOS parameters was also simulated and compared. The result shows that CMOS-based circuit requires 418.6 μW while CNFET-based circuit consumes 352.1 μW only. Further, the proposed circuit is used to realize a CNFET-based instrumentation amplifier with digitally programmable gain. The amplifier has a CMRR of 100 dB and ICMR equal to 0.806 V. The 3 dB bandwidth of the amplifier is 11.78 GHz which is suitable for the applications like navigation, radar instrumentation, and high-frequency signal amplification and conditioning.

  14. Optical and digital GaAs technologies for signal-processing applications; Proceedings of the Meeting, Orlando, FL, Apr. 16-18, 1990

    Science.gov (United States)

    Bendett, Mark P.; Butler, Daniel H., Jr.; Prabhakar, Arati; Yang, Andrew

    1990-10-01

    Practical problems that need to be solved for the introduction of optical modules into processing systems are reviewed. Some papers deal with the state of the art in such key devices as Bragg cells, spatial light modulators, and fast CCDs. Issues unique to optical packaging are also highlightened. New architectures to enable real-time operations are demonstrated, and optical interconnects for parallel processors are discussed. Particular attention is given to the status and operational advantages of government-sponsored efforts to upgrade existing military systems with digital GaAs signal processors and the state of the art in computer-aided design and advanced system architectures.

  15. LFI 30 and 44 GHz receivers Back-End Modules

    International Nuclear Information System (INIS)

    Artal, E; Aja, B; Fuente, M L de la; Pascual, J P; Mediavilla, A; Martinez-Gonzalez, E; Pradell, L; Paco, P de; Bara, M; Blanco, E; GarcIa, E; Davis, R; Kettle, D; Roddis, N; Wilkinson, A; Bersanelli, M; Mennella, A; Tomasi, M; Butler, R C; Cuttaia, F

    2009-01-01

    The 30 and 44 GHz Back End Modules (BEM) for the Planck Low Frequency Instrument are broadband receivers (20% relative bandwidth) working at room temperature. The signals coming from the Front End Module are amplified, band pass filtered and finally converted to DC by a detector diode. Each receiver has two identical branches following the differential scheme of the Planck radiometers. The BEM design is based on MMIC Low Noise Amplifiers using GaAs P-HEMT devices, microstrip filters and Schottky diode detectors. Their manufacturing development has included elegant breadboard prototypes and finally qualification and flight model units. Electrical, mechanical and environmental tests were carried out for the characterization and verification of the manufactured BEMs. A description of the 30 and 44 GHz Back End Modules of Planck-LFI radiometers is given, with details of the tests done to determine their electrical and environmental performances. The electrical performances of the 30 and 44 GHz Back End Modules: frequency response, effective bandwidth, equivalent noise temperature, 1/f noise and linearity are presented.

  16. 640 GHz Heterodyne Polarimeter, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is responsive to NASA SBIR Subtopic S1.02: Microwave Technologies for Remote Sensing, specifically the interest in the development of a 640 GHz...

  17. Digital Beamforming Scatterometer

    Science.gov (United States)

    Rincon, Rafael F.; Vega, Manuel; Kman, Luko; Buenfil, Manuel; Geist, Alessandro; Hillard, Larry; Racette, Paul

    2009-01-01

    This paper discusses scatterometer measurements collected with multi-mode Digital Beamforming Synthetic Aperture Radar (DBSAR) during the SMAP-VEX 2008 campaign. The 2008 SMAP Validation Experiment was conducted to address a number of specific questions related to the soil moisture retrieval algorithms. SMAP-VEX 2008 consisted on a series of aircraft-based.flights conducted on the Eastern Shore of Maryland and Delaware in the fall of 2008. Several other instruments participated in the campaign including the Passive Active L-Band System (PALS), the Marshall Airborne Polarimetric Imaging Radiometer (MAPIR), and the Global Positioning System Reflectometer (GPSR). This campaign was the first SMAP Validation Experiment. DBSAR is a multimode radar system developed at NASA/Goddard Space Flight Center that combines state-of-the-art radar technologies, on-board processing, and advances in signal processing techniques in order to enable new remote sensing capabilities applicable to Earth science and planetary applications [l]. The instrument can be configured to operate in scatterometer, Synthetic Aperture Radar (SAR), or altimeter mode. The system builds upon the L-band Imaging Scatterometer (LIS) developed as part of the RadSTAR program. The radar is a phased array system designed to fly on the NASA P3 aircraft. The instrument consists of a programmable waveform generator, eight transmit/receive (T/R) channels, a microstrip antenna, and a reconfigurable data acquisition and processor system. Each transmit channel incorporates a digital attenuator, and digital phase shifter that enables amplitude and phase modulation on transmit. The attenuators, phase shifters, and calibration switches are digitally controlled by the radar control card (RCC) on a pulse by pulse basis. The antenna is a corporate fed microstrip patch-array centered at 1.26 GHz with a 20 MHz bandwidth. Although only one feed is used with the present configuration, a provision was made for separate corporate

  18. Mixed-signal early vision chip with embedded image and programming memories and digital I/O

    Science.gov (United States)

    Linan-Cembrano, Gustavo; Rodriguez-Vazquez, Angel; Dominguez-Castro, Rafael; Espejo, Servando

    2003-04-01

    From a system level perspective, this paper presents a 128x128 flexible and reconfigurable Focal-Plane Analog Programmable Array Processor, which has been designed as a single chip in a 0.35μm standard digital 1P-5M CMOS technology. The core processing array has been designed to achieve high-speed of operation and large-enough accuracy (~7bit) with low power consumption. The chip includes on-chip program memory to allow for the execution of complex, sequential and/or bifurcation flow image processing algorithms. It also includes the structures and circuits needed to guarantee its embedding into conventional digital hosting systems: external data interchange and control are completely digital. The chip contains close to four million transistors, 90% of them working in analog mode. The chip features up to 330GOPs (Giga Operations per second), and uses the power supply (180GOP/Joule) and the silicon area (3.8 GOPS/mm2) efficiently, as it is able to maintain VGA processing throughputs of 100Frames/s with about 15 basic image processing tasks on each frame.

  19. Gallium arsenide digital integrated circuits for controlling SLAC CW-RF systems

    International Nuclear Information System (INIS)

    Ronan, M.T.; Lee, K.L.; Corredoura, P.; Judkins, J.G.

    1989-01-01

    In order to fill the PEP and SPEAR storage rings with beams from the SLC linac and damping rings, precise control of the linac subharmonic buncher and the damping ring RF is required. Recently several companies have developed resettable GaAs master/slave D-type flip-flops which are capable of operating at frequencies of 3 GHz and higher. Using these digital devices as frequency dividers, one can phase shift the SLAC CW-RF systems to optimize the timing for filling the storage rings. The authors have evaluated the performance of integrated circuits from two vendors for our particular application. Using microstrip circuit techniques, they have built and operated in the accelerator several chassis to synchronize a reset signal from the storage rings to the SLAC 2.856 GHz RF and to phase shift divide-by-four and divide-by-sixteen frequency dividers to the nearest 350 psec bucket required for filling

  20. Antenne Design for 24 GHz and 60 GHz Emerging Microwave Applications

    NARCIS (Netherlands)

    Jansen, F.; Dolmans, W.M.C.

    2006-01-01

    In this project integrated antennas on a LAMP3 substrate for automotive radar systems at 24 GHz and wireless networks at 60 GHz have been designed. The most severe requirements on the antennas were the large bandwidth, which can not be met with conventional patch antennas. A tapered slot antenna and

  1. Radioastronomic signal processing cores for the SKA radio telescope

    Science.gov (United States)

    Comorett, G.; Chiarucc, S.; Belli, C.

    Modern radio telescopes require the processing of wideband signals, with sample rates from tens of MHz to tens of GHz, and are composed from hundreds up to a million of individual antennas. Digital signal processing of these signals include digital receivers (the digital equivalent of the heterodyne receiver), beamformers, channelizers, spectrometers. FPGAs present the advantage of providing a relatively low power consumption, relative to GPUs or dedicated computers, a wide signal data path, and high interconnectivity. Efficient algorithms have been developed for these applications. Here we will review some of the signal processing cores developed for the SKA telescope. The LFAA beamformer/channelizer architecture is based on an oversampling channelizer, where the channelizer output sampling rate and channel spacing can be set independently. This is useful where an overlap between adjacent channels is required to provide an uniform spectral coverage. The architecture allows for an efficient and distributed channelization scheme, with a final resolution corresponding to a million of spectral channels, minimum leakage and high out-of-band rejection. An optimized filter design procedure is used to provide an equiripple response with a very large number of spectral channels. A wideband digital receiver has been designed in order to select the processed bandwidth of the SKA Mid receiver. The receiver extracts a 2.5 MHz bandwidth form a 14 GHz input bandwidth. The design allows for non-integer ratios between the input and output sampling rates, with a resource usage comparable to that of a conventional decimating digital receiver. Finally, some considerations on quantization of radioastronomic signals are presented. Due to the stochastic nature of the signal, quantization using few data bits is possible. Good accuracies and dynamic range are possible even with 2-3 bits, but the nonlinearity in the correlation process must be corrected in post-processing. With at least 6

  2. A 31 GHz Survey of Low-Frequency Selected Radio Sources

    Science.gov (United States)

    Mason, B. S.; Weintraub, L.; Sievers, J.; Bond, J. R.; Myers, S. T.; Pearson, T. J.; Readhead, A. C. S.; Shepherd, M. C.

    2009-10-01

    The 100 m Robert C. Byrd Green Bank Telescope and the 40 m Owens Valley Radio Observatory telescope have been used to conduct a 31 GHz survey of 3165 known extragalactic radio sources over 143 deg2 of the sky. Target sources were selected from the NRAO VLA Sky Survey in fields observed by the Cosmic Background Imager (CBI); most are extragalactic active galactic nuclei (AGNs) with 1.4 GHz flux densities of 3-10 mJy. The resulting 31 GHz catalogs are presented in full online. Using a maximum-likelihood analysis to obtain an unbiased estimate of the distribution of the 1.4-31 GHz spectral indices of these sources, we find a mean 31-1.4 GHz flux ratio of 0.110 ± 0.003 corresponding to a spectral index of α = -0.71 ± 0.01 (S ν vprop να) 9.0% ± 0.8% of sources have α > - 0.5 and 1.2% ± 0.2% have α > 0. By combining this spectral-index distribution with 1.4 GHz source counts, we predict 31 GHz source counts in the range 1 mJy S 31) = (16.7 ± 1.7) deg-2(S 31/1 mJy)-0.80±0.07. We also assess the contribution of mJy-level (S 1.4 GHz < 3.4 mJy) radio sources to the 31 GHz cosmic microwave background power spectrum, finding a mean power of ell(ell + 1)C src ell/(2π) = 44 ± 14 μK2 and a 95% upper limit of 80 μK2 at ell = 2500. Including an estimated contribution of 12 μK2 from the population of sources responsible for the turn-up in counts below S 1.4 GHz = 1 mJy, this amounts to 21% ± 7% of what is needed to explain the CBI high-ell excess signal, 275 ± 63 μK2. These results are consistent with other measurements of the 31 GHz point-source foreground.

  3. Pulse pile-up and dead time corrections for digitized signals from a BaF{sub 2} calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza, E., E-mail: emilio.mendoza@ciemat.es [CIEMAT, Avda. Complutense 40, 28040 Madrid (Spain); Cano-Ott, D., E-mail: daniel.cano@ciemat.es [CIEMAT, Avda. Complutense 40, 28040 Madrid (Spain); Guerrero, C., E-mail: carlos.guerrero@cern.ch [CERN, Physics Department, Geneva (Switzerland); CIEMAT, Avda. Complutense 40, 28040 Madrid (Spain); Berthoumieux, E., E-mail: Eric.Berthoumieux@cea.fr [CEA/Saclay - IRFU, Gif-sur-Yvette (France); CERN, Physics Department, Geneva (Switzerland)

    2014-12-21

    The pulse pile-up and associated dead time effects in an {sup 243}Am(n,γ) cross section measurement with a BaF{sub 2} Total Absorption Calorimeter at the CERN n{sub T}OF facility have been characterized. In this case, reliable corrections of these effects are crucial because of the complex detector configuration and of the high count rate induced by the sample activity of 50 MBq. The techniques, which have been developed for offline processing of the present data, may be of general interest for the analysis of other experiments using digital acquisition systems.

  4. THz photonic wireless links with 16-QAM modulation in the 375-450 GHz band

    DEFF Research Database (Denmark)

    Jia, Shi; Yu, Xianbin; Hu, Hao

    2016-01-01

    We propose and experimentally demonstrate THz photonic wireless communication systems with 16-QAM modulation in the 375-450 GHz band. The overall throughput reaches as high as 80 Gbit/s by exploiting four THz channels with 5 Gbaud 16-QAM baseband modulation per channel. We create a coherent optic...... signal transmitter and the THz wireless transmitter with negligible induced power penalty....

  5. Use of the 37-38 GHz and 40-40.5 GHz Ka-bands for Deep Space Communications

    Science.gov (United States)

    Morabito, David; Hastrup, Rolf

    2004-01-01

    This paper covers a wide variety of issues associated with the implementation and use of these frequency bands for deep space communications. Performance issues, such as ground station pointing stability, ground antenna gain, antenna pattern, and propagation effects such as due to atmospheric, charged-particle and space loss at 37 GHz, will be addressed in comparison to the 32 GHz Ka-band deep space allocation. Issues with the use of and competition for this spectrum also will be covered. The state of the hardware developed (or proposed) for operating in this frequency band will be covered from the standpoint of the prospects for achieving higher data rates that could be accommodated in the available bandwidth. Hardware areas to be explored include modulators, digital-to-analog converters, filters, power amplifiers, receivers, and antennas. The potential users of the frequency band will be explored as well as their anticipated methods to achieve the potential high data rates and the implications of the competition for bandwidth.

  6. Results of the Ongoing Monitoring of the Position of a Geostationary Telecommunication Satellite by the Method of Spatially Separated Basis Receiving of Digital Satellite Television Signals

    Science.gov (United States)

    Bushuev, F.; Kaliuzhnyi, M.; Sybiryakova, Y.; Shulga, O.; Moskalenko, S.; Balagura, O.; Kulishenko, V.

    2016-10-01

    The results of the ongoing monitoring of the position of geostationary telecommunication satellite Eutelsat-13B (13° East) are presented in the article. The results were obtained using a radio engineering complex (RC) of four stations receiving digital satellite television and a data processing centre. The stations are located in Kyiv, Mukachevo, Kharkiv and Mykolaiv. The equipment of each station allows synchronous recording (by the GPS) of fragments of DVB-S signal from the quadrature detector output of the satellite television receiver. Samples of the complex signal are archived and sent to the data processing center through the Internet. Here three linearly independent slant range differences (Δr) for three pairs of the stations are determined as a result of correlation processing of received signals. Every second measured values of Δr are used to calculate Cartesian coordinates (XYZ) of the satellite in the coordinate system WGS84 by multilateration method. The time series of Δr, X, Y and Z obtained during continuous observations from March to May 2015 are presented in the article. Single-measurement errors of Δr, X, Y and Z are equal to 2.6 m, 3540 m, 705 m and 455 m, respectively. The complex is compared with known analogues. Ways of reduction of measurement errors of satellite coordinates are considered. The radio engineering complex could be considered a prototype of a system of independent ongoing monitoring of the position of geostationary telecommunication satellites.

  7. Input/output Buffer based Vedic Multiplier Design for Thermal Aware Energy Efficient Digital Signal Processing on 28nm FPGA

    DEFF Research Database (Denmark)

    Goswami, Kavita; Pandey, Bishwajeet; Hussain, Dil muhammed Akbar

    2016-01-01

    Programmable Gate Array (FPGA) in order to reduce the development cost. The development cost for Application Specific Integrated Circuits (ASICs) are high in compare to FPGA. Selection of the most energy efficient IO standards in place of signal gating is the main design methodology for design of energy...

  8. Digital Switching CMOS Power Amplifier for Multiband and Multimode Handset Applications

    Science.gov (United States)

    Nakatani, Toshifumi

    This thesis is directed towards the development of a digitally-assisted radio frequency power amplifier (RF PA) which is one of the potential solutions to realize a multiband and multimode transmitter with high efficiency for handset applications. To improve efficiency and linearity in multiple conditions, PA circuits and digital signal processing (DSP) algorithms are co-designed. In the dissertation, a proposed architecture employs a current-mode class-D (CMCD) configuration for high efficiency, and a polar modulation scheme driven by digital inputs. Detail design, fabrication and experimental results are given for circuit implementation and DSP of this architecture. First, a multiband watt-class complementary metal-oxide-semiconductor (CMOS) PA is demonstrated using 0.15 um CMOS integrated circuits (ICs), off-chip inductor and balun. To obtain high breakdown voltage, stacked field effect transistors (FETs) are used. The CMCD PA is tuned by band-switching capacitors, operating in the 0.7-1.8 GHz frequency band. The overall efficiencies of 27.1 / 25.6 % are achieved at 30.2 / 28.9 dBm CW output powers and 0.85 / 1.75 GHz carrier frequencies, respectively. Next, to achieve wide output power dynamic range, an architecture consisting of small segmented unti-cells is introduced into the PA, where multiple three-state unit-cells are used and the state of each unit-cell is controlled to provide a specific output power. The overall dynamic ranges are expanded to approximately 90 dB and 85 dB at and 0.85 / 1.75 GHz, respectively. The dissertation then presents digital modulation algorithms. The digital compensation techniques are developed to maintain linearity of an envelope modulator of the polar transmitter. A new digital pulse width modulation algorithm is also shown to partially suppress spurious signals associated with the digital input envelope signal. When wideband code-division multiple access (WCDMA) modulation is implemented, spur suppression of 9-10 dB is

  9. Indoor Propagation Measurement for WLAN Systems Operating in 2.45 GHz ISM Band

    Directory of Open Access Journals (Sweden)

    P. Pechac

    2002-12-01

    Full Text Available For a planning of indoor Wireless LAN systems working in the ISMband, the signal propagation prediction is needed. In this article, themeasurement campaign based on two types of measurements at 2.45 GHz isintroduced. The first type of the measurement was a classicalnarrowband signal level measurement within indoor scenario withoutpresence of people. The aim of this measurement was to find empiricalparameters for COST231 Multi-Wall and One-Slope models. In order tostatistically describe the time varying nature of the received envelopeof the signal, at WLAN 2.45 GHz band, the second part of measurementcampaign was accomplished. In this case, the signal level was measuredusing commercial WLAN PCMCIA cards in two notebooks. Probabilitydensity functions and corresponding cumulative distribution functionswere set and discussed based on the specific locations and orientationof one of the notebooks. Results from both measurement campaigns werecompared and conclusions are drawn for the needs of practical planningof indoor WLAN systems coverage.

  10. Application of digital signal processing methods for the diagnosis of respiration disorders during sleep with the use of plethysmographic wave analysis

    Science.gov (United States)

    Hatlinski, Grzegorz J.; Kornacki, Witold; Kukwa, Andrzej; Dobrowiecka, Bozena; Pikiel, Marek

    2004-07-01

    This paper proposes non-invasive solution to the problem of sleep apnea diagnosis especially in small children when sudden death syndrome is suspected. Plethysmographic wave analysis and digital signal processing algorithms are applied in order to find the effect invoked by respiratory movements of sleeping patients so as to diagnose the sleep apnea syndrome. The practical results of finding solution to problems mentioned above will be the possibility of algorithms implementation in a portable intelligent measurement system with a non-invasive monitoring of respiratory action. It works without any disturbances of sleep and respiratory movements especially in small children what could make possible in the future when continuous monitoring were applied to prevent sudden death syndrome occurrence.

  11. Single Event Upset Analysis: On-orbit performance of the Alpha Magnetic Spectrometer Digital Signal Processor Memory aboard the International Space Station

    Science.gov (United States)

    Li, Jiaqiang; Choutko, Vitaly; Xiao, Liyi

    2018-03-01

    Based on the collection of error data from the Alpha Magnetic Spectrometer (AMS) Digital Signal Processors (DSP), on-orbit Single Event Upsets (SEUs) of the DSP program memory are analyzed. The daily error distribution and time intervals between errors are calculated to evaluate the reliability of the system. The particle density distribution of International Space Station (ISS) orbit is presented and the effects from the South Atlantic Anomaly (SAA) and the geomagnetic poles are analyzed. The impact of solar events on the DSP program memory is carried out combining data analysis and Monte Carlo simulation (MC). From the analysis and simulation results, it is concluded that the area corresponding to the SAA is the main source of errors on the ISS orbit. Solar events can also cause errors on DSP program memory, but the effect depends on the on-orbit particle density.

  12. Research on control law accelerator of digital signal process chip TMS320F28035 for real-time data acquisition and processing

    Science.gov (United States)

    Zhao, Shuangle; Zhang, Xueyi; Sun, Shengli; Wang, Xudong

    2017-08-01

    TI C2000 series digital signal process (DSP) chip has been widely used in electrical engineering, measurement and control, communications and other professional fields, DSP TMS320F28035 is one of the most representative of a kind. When using the DSP program, need data acquisition and data processing, and if the use of common mode C or assembly language programming, the program sequence, analogue-to-digital (AD) converter cannot be real-time acquisition, often missing a lot of data. The control low accelerator (CLA) processor can run in parallel with the main central processing unit (CPU), and the frequency is consistent with the main CPU, and has the function of floating point operations. Therefore, the CLA coprocessor is used in the program, and the CLA kernel is responsible for data processing. The main CPU is responsible for the AD conversion. The advantage of this method is to reduce the time of data processing and realize the real-time performance of data acquisition.

  13. Monitoring of the Orbital Position of a Geostationary Satellite by the Spatially Separated Reception of Signals of Digital Satellite Television

    Directory of Open Access Journals (Sweden)

    Kaliuzny, M.P.

    2017-01-01

    Full Text Available The results of the determination of the geostationary satellite «Eutelsat-13B» orbital position obtained during 2015-2016 years using European stations’ network for reception of DVB-S signals from the satellite are presented. The network consists of five stations located in Ukraine and Latvia. The stations are equipped with a radio engineering complex developed by the RI «MAO». The measured parameter is a time difference of arrival (TDOA of the DVB-S signals to the stations of the network. The errors of TDOA determination and satellite coordinates, obtained using a numerical model of satellite motion, are equal ±2.6m and ±35m respectively. Software implementation of the numerical model is taken from the free space dynamics library OREKIT.

  14. Digital voltmeter

    International Nuclear Information System (INIS)

    Yohannes Kamadi; Soekarno.

    1976-01-01

    The electrical voltage measuring equipment with digital display has been made. This equipment uses four digits display with single polarity measurement and integrating system. Pulses from the oscillator will be counted and converted to the staircase voltages, and compared to the voltage measured. When the balance is already achieved, the pulse will appear at the comparator circuit. This pulse will be used to trigger univibrator circuit. The univibrator output is used as signal for stopping the counting, and when reading time T already stops, the counting system will be reset. (authors)

  15. Single- and Multiband OFDM Photonic Wireless Links in the 75−110 GHz Band Employing Optical Combs

    DEFF Research Database (Denmark)

    Beltrán, M.; Deng, Lei; Pang, Xiaodan

    2012-01-01

    The photonic generation of electrical orthogonal frequency-division multiplexing (OFDM) modulated wireless signals in the 75−110 GHz band is experimentally demonstrated employing in-phase/quadrature electrooptical modulation and optical heterodyn upconversion. The wireless transmission of 16......-quadrature-amplitude-modulation OFDM signals is demonstrated with a bit error rate performance within the forward error correction limits. Signals of 19.1 Gb/s in 6.3-GHz bandwidth are transmitted over up to 1.3-m wireless distance. Optical comb generation is further employed to support different channels...

  16. The method of «blind» carrier frequency estimation of radio signals with linear digital modulation

    Directory of Open Access Journals (Sweden)

    Nahornyuk О.А.

    2017-04-01

    Full Text Available Carrier frequency estimation in the conditions of a priori uncertainty of signal modulation and parameters is prerequisite for realization of frequency synchronization circuits in software-defined radio. To implement this operation the method of «blind» carrier frequency estimation of radio signals with amplitude, phase and quadrature-amplitude shift keying, which does not require prior information about modulation type, signal and communication channel parameters, is proposed in the article. The basis of method is calculation of constellation symbols cross-correlation and clock synchronization by Gardner method. As opposed to known approaches proposed method does not require two-dimensional objective function calculation which can reduce the number of computing operations. This is achieved by implementation of previous clock synchronization and reducing the two-dimensional objective function in one-dimensional. Verification of developed method is carried out by statistical modeling using more than 20 types of phase constellations. The practical significance of received results consists in reduction of carrier frequency estimation time and simplification of practical implementation at the expense of employment of approved clock synchronization circuits.

  17. A multi-GHz chaotic optoelectronic oscillator based on laser terminal voltage

    International Nuclear Information System (INIS)

    Chang, C. Y.; Choi, Daeyoung; Locquet, A.; Wishon, Michael J.; Citrin, D. S.; Merghem, K.; Ramdane, Abderrahim; Martinez, A.; Lelarge, François

    2016-01-01

    A multi-GHz chaotic optoelectronic oscillator based on an external cavity semiconductor laser (ECL) is demonstrated. Unlike the standard optoelectronic oscillators for microwave applications, we do not employ the dynamic light output incident on a photodiode to generate the microwave signal, but instead generate the microwave signal directly by measuring the terminal voltage V(t) of the laser diode of the ECL under constant-current operation, thus obviating the photodiode entirely.

  18. A 24GHz Radar Receiver in CMOS

    NARCIS (Netherlands)

    Kwok, K.C.

    2015-01-01

    This thesis investigates the system design and circuit implementation of a 24GHz-band short-range radar receiver in CMOS technology. The propagation and penetration properties of EM wave offer the possibility of non-contact based remote sensing and through-the-wall imaging of distance stationary or

  19. Digital dewaxing of Raman signals: discrimination between nevi and melanoma spectra obtained from paraffin-embedded skin biopsies.

    Science.gov (United States)

    Tfayli, Ali; Gobinet, Cyril; Vrabie, Valeriu; Huez, Regis; Manfait, Michel; Piot, Olivier

    2009-05-01

    Malignant melanoma (MM) is the most severe tumor affecting the skin and accounts for three quarters of all skin cancer deaths. Raman spectroscopy is a promising nondestructive tool that has been increasingly used for characterization of the molecular features of cancerous tissues. Different multivariate statistical analysis techniques are used in order to extract relevant information that can be considered as functional spectroscopic descriptors of a particular pathology. Paraffin embedding (waxing) is a highly efficient process used to conserve biopsies in tumor banks for several years. However, the use of non-dewaxed formalin-fixed paraffin-embedded tissues for Raman spectroscopic investigations remains very restricted, limiting the development of the technique as a routine analytical tool for biomedical purposes. This is due to the highly intense signal of paraffin, which masks important vibrations of the biological tissues. In addition to being time consuming and chemical intensive, chemical dewaxing methods are not efficient and they leave traces of the paraffin in tissues, which affects the Raman signal. In the present study, we use independent component analysis (ICA) on Raman spectral images collected on melanoma and nevus samples. The sources obtained from these images are then used to eliminate, using non-negativity constrained least squares (NCLS), the paraffin contribution from each individual spectrum of the spectral images of nevi and melanomas. Corrected spectra of both types of lesion are then compared and classified into dendrograms using hierarchical cluster analysis (HCA).

  20. Low-Noise MMIC Amplifiers for 120 to 180 GHz

    Science.gov (United States)

    Pukala, David; Samoska, Lorene; Peralta, Alejandro; Bayuk, Brian; Grundbacher, Ron; Oliver, Patricia; Cavus, Abdullah; Liu, Po-Hsin

    2009-01-01

    Three-stage monolithic millimeter-wave integrated-circuit (MMIC) amplifiers capable of providing useful amounts of gain over the frequency range from 120 to 180 GHz have been developed as prototype low-noise amplifiers (LNAs) to be incorporated into instruments for sensing cosmic microwave background radiation. There are also potential uses for such LNAs in electronic test equipment, passive millimeter- wave imaging systems, radar receivers, communication receivers, and systems for detecting hidden weapons. The main advantage afforded by these MMIC LNAs, relative to prior MMIC LNAs, is that their coverage of the 120-to-180-GHz frequency band makes them suitable for reuse in a wider variety of applications without need to redesign them. Each of these MMIC amplifiers includes InP transistors and coplanar waveguide circuitry on a 50- mthick chip (see Figure 1). Coplanar waveguide transmission lines are used for both applying DC bias and matching of input and output impedances of each transistor stage. Via holes are incorporated between top and bottom ground planes to suppress propagation of electromagnetic modes in the substrate. On the basis of computational simulations, each of these amplifiers was expected to operate with a small-signal gain of 14 dB and a noise figure of 4.3 dB. At the time of writing this article, measurements of noise figures had not been reported, but on-chip measurements had shown gains approaching their simulated values (see Figure 2).

  1. Test results from the LLNL 250 GHz CARM experiment

    International Nuclear Information System (INIS)

    Kulke, B.; Caplan, M.; Bubp, D.; Houck, T.; Rogers, D.; Trimble, D.; VanMaren, R.; Westenskow, G.; McDermott, D.B.; Luhmann, N.C. Jr.; Danly, B.

    1991-01-01

    The authors have completed the initial phase of a 250 GHz CARM experiment, driven by the 2 MeV, 1 kA, 30 ns induction linac at the LLNL ARC facility. A non-Brillouin, solid, electron beam is generated from a flux-threaded, thermionic cathode. As the beam traverses a 10 kG plateau produced by a superconducting magnet, ten percent of the beam energy is converted into rotational energy in a bifilar helix wiggler that produces a spiraling, 50 G, transverse magnetic field. The beam is then compressed to a 5 mm diameter as it drifts into a 30 kG plateau. For the present experiment, the CARM interaction region consisted of a single Bragg section resonator, followed by a smooth-bore amplifier section. Using high-pass filters, they have observed broadband output signals estimated to be at the several megawatt level in the range 140 to over 230 GHz. This is consistent with operation as a superradiant amplifier. Simultaneously, they also observed K a band power levels near 3 MW

  2. Estimation of Electrical Properties of Hidden Objects Using Microwave Signals

    Directory of Open Access Journals (Sweden)

    Steponas AŠMONTAS

    2014-06-01

    Full Text Available Pulsed excitation of a horn antenna for generating large B wideband electromagnetic pulses was used. The antenna was excited by electrical pulses with rise time of 200 ps and pulse voltage of 15 V. The spectral properties of the electromagnetic pulses were investigated using different wide band antennas and (0 – 18 GHz passband sampling oscilloscope. It was found that the signal spectra is wide and ranges from 0.3 GHz to higher than 12 GHz. Hollow cylinders made from opaque for visible light materials were used to hide other cylinders with certain electrical properties. To reveal their presence we employ the electromagnetic pulses. Transmitted through and reflected from investigated objects pulses were received by several antennas having different frequency ranges and detected to obtain needed information. The experiments show that analyzing this information leads to conclusions about the presence of the object and its electrical properties. This methodic supposedly can be employed to disclose electrical properties of objects having complex electrical properties if broadband amplifiers and digital oscilloscopes are used. DOI: http://dx.doi.org/10.5755/j01.ms.20.2.6331

  3. The front-end analog and digital signal processing electronics for the drift chambers of the Stanford Large Detector

    International Nuclear Information System (INIS)

    Haller, G.M.; Freytag, D.R.; Fox, J.; Olsen, J.; Paffrath, L.; Yim, A.; Honma, A.

    1990-10-01

    The front-end signal processing electronics for the drift-chambers of the Stanford Large Detector (SLD) at the Stanford Linear Collider is described. The system is implemented with printed-circuit boards which are shaped for direct mounting on the detector. Typically, a motherboard comprises 64 channels of transimpedance amplification and analog waveform sampling, A/D conversion, and associated control and readout circuitry. The loaded motherboard thus forms a processor which records low-level wave forms from 64 detector channels and transforms the information into a 64 k-byte serial data stream. In addition, the package performs calibration functions, measures leakage currents on the wires, and generates wire hit patterns for triggering purposes. The construction and operation of the electronic circuits utilizing monolithic, hybridized, and programmable components are discussed

  4. Development of Digital Signal Processing with FPGAs for the Readout of the ATLAS Liquid Argon Calorimeter at HL-LHC

    CERN Document Server

    Stärz, Steffen; Zuber, K

    2010-01-01

    The Liquid Argon calorimeter of the ATLAS detector at CERN in Geneva is supposed to be equipped with advanced readout electronics for the operation at High Luminosity LHC. In this diploma thesis the aspect of fast serial data transmission and data processing to be used for the communication between different readout modules and data storage buffers of the trigger shall be further developed. Furthermore, the main focus is put on first preparation of the detector raw data with regard to a signal correction using a FIR filter. It is aimed at a most efficient, most resource economising and minimal latency causing solution that allows to process the huge amount of upcoming detector raw data in real time. Therefore a via UDP/IP reconfigurable prototype of a 5-stage FIR filter with Gigabit Ethernet Interface was implemented in a Xilinx Virtex-5 FPGA. The performance reached is fully within the the requirements for the upgraded calorimeter readout of ATLAS.

  5. Digital positron annihilation spectrometer

    International Nuclear Information System (INIS)

    Cheng Bin; Weng Huimin; Han Rongdian; Ye Bangjiao

    2010-01-01

    With the high speed development of digital signal process, the technique of the digitization and processing of signals was applied in the domain of a broad class of nuclear technique. The development of digital positron lifetime spectrometer (DPLS) is more promising than the conventional positron lifetime spectrometer equipped with nuclear instrument modules. And digital lifetime spectrometer has many advantages, such as low noise, long term stability, flexible online or offline digital processing, simple setup, low expense, easy to setting, and more physical information. Digital constant fraction discrimination is for timing. And a new method of optimizing energy windows setting for digital positron lifetime spectrometer is also developed employing the simulated annealing for the convenient use. The time resolution is 220ps and the count rate is 200cps. (authors)

  6. Digital watermark

    Directory of Open Access Journals (Sweden)

    Jasna Maver

    2000-01-01

    Full Text Available The huge amount of multimedia contents available on the World-Wide-Web is beginning to raise the question of their protection. Digital watermarking is a technique which can serve various purposes, including intellectual property protection, authentication and integrity verification, as well as visible or invisible content labelling of multimedia content. Due to the diversity of digital watermarking applicability, there are many different techniques, which can be categorised according to different criteria. A digital watermark can be categorised as visible or invisible and as robust or fragile. In contrast to the visible watermark where a visible pattern or image is embedded into the original image, the invisible watermark does not change the visual appearance of the image. The existence of such a watermark can be determined only through a watermark ex¬traction or detection algorithm. The robust watermark is used for copyright protection, while the fragile watermark is designed for authentication and integrity verification of multimedia content. A watermark must be detectable or extractable to be useful. In some watermarking schemes, a watermark can be extracted in its exact form, in other cases, we can detect only whether a specific given watermarking signal is present in an image. Digital libraries, through which cultural institutions will make multimedia contents available, should support a wide range of service models for intellectual property protection, where digital watermarking may play an important role.

  7. Comparison of advanced DSP techniques for spectrally efficient Nyquist-WDM signal generation using digital FIR filters at transmitters based on higher-order modulation formats

    Science.gov (United States)

    Weng, Yi; Wang, Junyi; Pan, Zhongqi

    2016-02-01

    To support the ever-increasing demand for high-speed optical communications, Nyquist spectral shaping serves as a promising technique to improve spectral efficiency (SE) by generating near-rectangular spectra with negligible crosstalk and inter-symbol interference in wavelength-division-multiplexed (WDM) systems. Compared with specially-designed optical methods, DSP-based electrical filters are more flexible as they can generate different filter shapes and modulation formats. However, such transmitter-side pre-filtering approach is sensitive to the limited taps of finite-impulse-response (FIR) filter, for the complexity of the required DSP and digital-to-analog converter (DAC) is limited by the cost and power consumption of optical transponder. In this paper, we investigate the performance and complexity of transmitter-side FIR-based DSP with polarization-division-multiplexing (PDM) high-order quadrature-amplitude-modulation (QAM) formats. Our results show that Nyquist 64-QAM, 16-QAM and QPSK WDM signals can be sufficiently generated by digital FIR filters with 57, 37, and 17 taps respectively. Then we explore the effects of the required spectral pre-emphasis, bandwidth and resolution on the performance of Nyquist-WDM systems. To obtain negligible OSNR penalty with a roll-off factor of 0.1, two-channel-interleaved DAC requires a Gaussian electrical filter with the bandwidth of 0.4-0.6 times of the symbol rate for PDM-64QAM, 0.35-0.65 times for PDM-16QAM, and 0.3-0.8 times for PDM-QPSK, with required DAC resolutions as 8, 7, 6 bits correspondingly. As a tradeoff, PDM-64QAM can be a promising candidate for SE improvement in next-generation optical metro networks.

  8. Enhancing the Bandwidth Utilization in the Millimeter Wave Band and to Modernize the Digital Signal Processing Laboratory at the California State University, Bakersfield

    Science.gov (United States)

    2016-03-16

    mention that current standards, e.g., Wireless Gigabit Alliance ( WiGig ) and IEEE 802.11ad operate over the unlicensed 60 GHz frequency band. Given large...current standards, e.g., WiGig and IEEE 802.11ad, support both single carrier modulation and multi- carrier orthogonal frequency division multiplexing

  9. Effects of exposure equalization on image signal-to-noise ratios in digital mammography: A simulation study with an anthropomorphic breast phantom

    International Nuclear Information System (INIS)

    Liu Xinming; Lai Chaojen; Whitman, Gary J.; Geiser, William R.; Shen Youtao; Yi Ying; Shaw, Chris C.

    2011-01-01

    Purpose: The scan equalization digital mammography (SEDM) technique combines slot scanning and exposure equalization to improve low-contrast performance of digital mammography in dense tissue areas. In this study, full-field digital mammography (FFDM) images of an anthropomorphic breast phantom acquired with an anti-scatter grid at various exposure levels were superimposed to simulate SEDM images and investigate the improvement of low-contrast performance as quantified by primary signal-to-noise ratios (PSNRs). Methods: We imaged an anthropomorphic breast phantom (Gammex 169 ''Rachel,'' Gammex RMI, Middleton, WI) at various exposure levels using a FFDM system (Senographe 2000D, GE Medical Systems, Milwaukee, WI). The exposure equalization factors were computed based on a standard FFDM image acquired in the automatic exposure control (AEC) mode. The equalized image was simulated and constructed by superimposing a selected set of FFDM images acquired at 2, 1, 1/2, 1/4, 1/8, 1/16, and 1/32 times of exposure levels to the standard AEC timed technique (125 mAs) using the equalization factors computed for each region. Finally, the equalized image was renormalized regionally with the exposure equalization factors to result in an appearance similar to that with standard digital mammography. Two sets of FFDM images were acquired to allow for two identically, but independently, formed equalized images to be subtracted from each other to estimate the noise levels. Similarly, two identically but independently acquired standard FFDM images were subtracted to estimate the noise levels. Corrections were applied to remove the excess system noise accumulated during image superimposition in forming the equalized image. PSNRs over the compressed area of breast phantom were computed and used to quantitatively study the effects of exposure equalization on low-contrast performance in digital mammography. Results: We found that the highest achievable PSNR improvement factor was 1.89 for

  10. 10 GHz ECRIS for Warsaw Cyclotron

    CERN Document Server

    Sudlitz, K

    1999-01-01

    Cusp type, 10 GHz ECRIS has been built and tested earlier. For obtaining intensive beams, more relevant for cyclotron, cusp geometry has been replaced by hexapole. Discharge chamber (stainless steel, 50 mm diameter, 250 mm long) is an extension of a coaxial line, feeding RF (9,6 GHz, up to 200 W) to the plasma. The NdFeB hexapole (0,52 T on the surface) has been used. The axial magnetic field is created by water cooled coils. The axial injection line dedicated to K160 isochronous heavy ion cyclotron has been constructed. The line consists of Glaser lenses, double focusing magnet, solenoid and mirror type inflector. The system provides sufficient transmission of the beam from ECR ion source to the firsts orbits of the cyclotron for m/q ranging from 7 to 2. After successful initial tests which were done in July 1997 the ECRIS serves as an external source for Warsaw Cyclotron.

  11. SEVENTH HARMONIC 20 GHz CO-GENERATOR

    Energy Technology Data Exchange (ETDEWEB)

    Hirshfield, Jay L

    2014-04-08

    To satisfy the need for multi-MW rf sources in frequency ranges where commercial sources do not exist, a study was undertaken on a class of devices based on gyro-harmonic frequency multiplication. This mechanism relies upon adding energy in gyrating motion to a linear electron beam that traverses a rotating-mode TE111-mode drive cavity in a dc magnetic field. The beam then drifts along the magnetic field into a second cavity, operating in the TEn11-mode tuned to the nth harmonic of the drive cavity. Studies of this configuration have been carried out for 2 < n < 7. Results are given for multi-MW, efficient operation of a 7th harmonic device operating at 20 GHz, and a 2nd harmonic device operating at 22.4 GHz.

  12. Australia 31-GHz brightness temperature exceedance statistics

    Science.gov (United States)

    Gary, B. L.

    1988-01-01

    Water vapor radiometer measurements were made at DSS 43 during an 18 month period. Brightness temperatures at 31 GHz were subjected to a statistical analysis which included correction for the effects of occasional water on the radiometer radome. An exceedance plot was constructed, and the 1 percent exceedance statistics occurs at 120 K. The 5 percent exceedance statistics occurs at 70 K, compared with 75 K in Spain. These values are valid for all of the three month groupings that were studied.

  13. Computer-aided detection of microcalcifications in digital breast tomosynthesis (DBT): a multichannel signal detection approach on projection views

    Science.gov (United States)

    Wei, Jun; Chan, Heang-Ping; Hadjiiski, Lubomir; Helvie, Mark A.; Zhou, Chuan; Lu, Yao

    2012-03-01

    DBT is one of the promising imaging modalities that may improve the sensitivity and specificity for breast cancer detection. We are developing a computer-aided detection (CADe) system for clustered microcalcifications (MC) in DBT. A data set of two-view DBTs from 42 breasts was collected with a GE prototype system. We investigated a 2D approach to MC detection using projection view (PV) images rather than reconstructed 3D DBT volume. Our 2D approach consisted of two major stages: 1) detecting individual MC candidates on each PV, and 2) correlating the MC candidates from the different PVs and detecting clusters in the breast volume. With the MC candidates detected by prescreening on PVs, a trained multi-channel (MCH) filter bank was used to extract signal response from each MC candidate. A ray-tracing process was performed to fuse the MCH responses and localize the MC candidates in 3D using the geometrical information of the DBT system. Potential MC clusters were then identified by dynamic clustering of the MCs in 3D. A two-fold cross-validation method was used to train and test the CADe system. The detection performance of clustered MCs was assessed by free receiver operating characteristic (FROC) analysis. It was found that the CADe system achieved a case-based sensitivity of 90% at an average false positive rate of 2.1 clusters per DBT volume. Our study demonstrated that the CADe system using 2D MCH filter bank is promising for detection of clustered MCs in DBT.

  14. The Signal Distribution System

    CERN Document Server

    Belohrad, D; CERN. Geneva. AB Department

    2005-01-01

    For the purpose of LHC signal observation and high frequency signal distribution, the Signal Distribution System (SDS) was built. The SDS can contain up to 5 switching elements, where each element allows the user to switch between one of the maximum 8 bi-directional signals. The coaxial relays are used to switch the signals. Depending of the coaxial relay type used, the transfer bandwidth can go up to 18GHz. The SDS is controllable via TCP/IP, parallel port, or locally by rotary switch.

  15. Impedance matching for the reduction of signal reflection in high speed multilevel three-dimensional integrated chips

    Science.gov (United States)

    Xiaoxian, Liu; Zhangming, Zhu; Yintang, Yang; Fengjuan, Wang; Ruixue, Ding

    2014-01-01

    In high speed three-dimensional integrated circuits (3D ICs), through silicon via (TSV) insertion causes impedance discontinuities along the interconnect-TSV channel that results in signal reflection. As demonstrated for a two-plane interconnect structure connected by a TSV, we incorporate an appropriate capacitance at the junction to mitigate the signal reflection with gigascale frequencies. Based on 65 nm technology and S-parameter analysis, the decrease of signal reflection can be 189% at the tuned frequency of 5 GHz. Extending this method to the five-plane interconnect structure further, the reduction of signal reflection can achieve 400%. So we could broaden this method to any multilevel 3D interconnect structures. This method can also be applied to a circuit with tunable operating frequencies by digitally connecting the corresponding matching capacitance into the circuit through switches. There are remarkable improvements of the quality of the transmitting signals.

  16. 105 GHz Notch Filter Design for Collective Thomson Scattering

    DEFF Research Database (Denmark)

    Furtula, Vedran; Michelsen, Poul; Leipold, Frank

    2011-01-01

    A millimeter-wave notch filter with 105-GHz center frequency, >20-GHz passband coverage, and 1-GHz rejection bandwidth has been constructed. The design is based on a fundamental rectangular waveguide with cylindrical cavities coupled by narrow iris gaps, i.e., small elongated holes of negligible...... thickness. We use numerical simulations to study the sensitivity of the notch filter performance to changes in geometry and in material conductivity within a bandwidth of ±10 GHz. The constructed filter is tested successfully using a vector network analyzer monitoring a total bandwidth of 20 GHz....... The typical insertion loss in the passband is...

  17. DIGITAL SELF-OSCILLATING MODULATOR

    DEFF Research Database (Denmark)

    2007-01-01

    A digital self-oscillating modulator (1) having a digital reference signal as input (Vref) comprises a forward loop with a first output and a feedback loop. The feedback loop comprises a feedback block (18) having a transfer function (MFB) and a digital output. The forward loop comprises an alter......A digital self-oscillating modulator (1) having a digital reference signal as input (Vref) comprises a forward loop with a first output and a feedback loop. The feedback loop comprises a feedback block (18) having a transfer function (MFB) and a digital output. The forward loop comprises...

  18. Traceable calibration for a digital real-time oscilloscope with time interleaving architecture

    Science.gov (United States)

    Kim, Dongju; Lee, Joo-Gwang; Lee, Dong-Joon; Cho, Chihyun

    2018-01-01

    Impairments of analog-to-digital converters (ADCs) used in digital real-time oscilloscopes (DRTO) have caused inevitable signal distortions in measurements. To calibrate these errors with traceability, we propose a novel method that consists of two steps. First, each transfer function of the ADCs is measured using pulse trains from a photodiode calibrated up to 110 GHz. Each data set of the ADCs is superimposed to convert the repetitive pulse to a single pulse to solve the under-sampling problem of the separated data depending on each ADC. Then, the signals of the device under test (DUT) are also separated and superimposed depending on the ADCs, and they are calibrated in the frequency domain based on the measured transfer functions. After a calibration process, the data set is reconverted to the time domain to achieve traceable calibration. To verify our method, we have measured the output of another 70 GHz photodiode with a calibrated DRTO. In terms of results, time-interleaved errors are suppressed by more than 24 dB up to the bandwidth of the DRTO.

  19. Digital mineral logging system

    International Nuclear Information System (INIS)

    West, J.B.

    1980-01-01

    A digital mineral logging system acquires data from a mineral logging tool passing through a borehole and transmits the data uphole to an electronic digital signal processor. A predetermined combination of sensors, including a deviometer, is located in a logging tool for the acquisition of the desired data as the logging tool is raised from the borehole. Sensor data in analog format is converted in the logging tool to a digital format and periodically batch transmitted to the surface at a predetermined sampling rate. An identification code is provided for each mineral logging tool, and the code is transmitted to the surface along with the sensor data. The self-identifying tool code is transmitted to the digital signal processor to identify the code against a stored list of the range of numbers assigned to that type of tool. The data is transmitted up the d-c power lines of the tool by a frequency shift key transmission technique. At the surface, a frequency shift key demodulation unit transmits the decoupled data to an asynchronous receiver interfaced to the electronic digital signal processor. During a recording phase, the signals from the logging tool are read by the electronic digital signal processor and stored for later processing. During a calculating phase, the stored data is processed by the digital signal processor and the results are outputted to a printer or plotter, or both

  20. A comparison between the first-fit settings of two multichannel digital signal-processing strategies: music quality ratings and speech-in-noise scores.

    Science.gov (United States)

    Higgins, Paul; Searchfield, Grant; Coad, Gavin

    2012-06-01

    The aim of this study was to determine which level-dependent hearing aid digital signal-processing strategy (DSP) participants preferred when listening to music and/or performing a speech-in-noise task. Two receiver-in-the-ear hearing aids were compared: one using 32-channel adaptive dynamic range optimization (ADRO) and the other wide dynamic range compression (WDRC) incorporating dual fast (4 channel) and slow (15 channel) processing. The manufacturers' first-fit settings based on participants' audiograms were used in both cases. Results were obtained from 18 participants on a quick speech-in-noise (QuickSIN; Killion, Niquette, Gudmundsen, Revit, & Banerjee, 2004) task and for 3 music listening conditions (classical, jazz, and rock). Participants preferred the quality of music and performed better at the QuickSIN task using the hearing aids with ADRO processing. A potential reason for the better performance of the ADRO hearing aids was less fluctuation in output with change in sound dynamics. ADRO processing has advantages for both music quality and speech recognition in noise over the multichannel WDRC processing that was used in the study. Further evaluations of which DSP aspects contribute to listener preference are required.

  1. Hybrid opto-digital signal processing in 112 Gbit/s DP-16QAM and DP-QDB transmission for long-haul large-Aeff pure-silica-core fiber links

    DEFF Research Database (Denmark)

    Asif, Rameez; Ahmad, Ramshah; Basir, Rabeea

    2016-01-01

    By means of numerical simulations, we demonstrated that all-optical signal processing methods (XPM-suppressor module and in-line nonlinear equalization) significantly increase the system performance of digital nonlinear compensation (digital backward propagation) and improve the system performance...... in five-channel 112 Gbit/s DP-16QAM and DP-QDB transmission over 2400 km large- effective-area pure-silica-core fiber ((Formula presented.)-PSCF). The system performance is quantified with the help of Q-factor (dB) for both dispersion-managed and nondispersion-managed fiber links....

  2. An LTCC 94 GHz Antenna Array

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre, J; Pao, H; Lin, H; Garland, P; O' Neill, D; Horton, K

    2007-12-21

    An antenna array is designed in low-temperature cofired ceramic (LTCC) Ferro A6M{trademark} for a mm-wave application. The antenna is designed to operate at 94 GHz with a few percent bandwidth. A key manufacturing technology is the use of 3 mil diameter vias on a 6 mil pitch to construct the laminated waveguides that form the beamforming network and radiating elements. Measurements for loss in the laminated waveguide are presented. The slot-fed cavity-radiating element is designed to account for extremely tight mutual coupling between elements. The array incorporates a slot-fed multi-layer beamforming network.

  3. A 35-GHz radar for sensing applications

    Science.gov (United States)

    Park, J. S.; Nguyen, C.

    2010-04-01

    We report a millimeter-wave stepped-frequency radar operating from 29.72 to 37.7 GHz for sensing applications. The radar is implemented using coherent super-heterodyne scheme and completely realized using microwave and millimeterwave integrated circuits. The developed radar has been demonstrated for different sensing applications with high accuracy and resolution. It can be used for various sensing applications including pavement and bridge assessment, liquid-level measurement, detection and location of buried mines and unexploded ordnance (UXO), detection of intrusion to structures including important civil facilities, detection of slow moving objects, surveillance and monitoring of hidden activities and objects.

  4. Theoretical models for designing a 220-GHz folded waveguide backward wave oscillator

    Science.gov (United States)

    Cai, Jin-Chi; Hu, Lin-Lin; Ma, Guo-Wu; Chen, Hong-Bin; Jin, Xiao; Chen, Huai-Bi

    2015-06-01

    In this paper, the basic equations of beam-wave interaction for designing the 220 GHz folded waveguide (FW) backward wave oscillator (BWO) are described. On the whole, these equations are mainly classified into small signal model (SSM), large signal model (LSM), and simplified small signal model (SSSM). Using these linear and nonlinear one-dimensional (1D) models, the oscillation characteristics of the FW BWO of a given configuration of slow wave structure (SWS) can be calculated by numerical iteration algorithm, which is more time efficient than three-dimensional (3D) particle-in-cell (PIC) simulation. The SSSM expressed by analytical formulas is innovatively derived for determining the initial values of the FW SWS conveniently. The dispersion characteristics of the FW are obtained by equivalent circuit analysis. The space charge effect, the end reflection effect, the lossy wall effect, and the relativistic effect are all considered in our models to offer more accurate results. The design process of the FW BWO tube with output power of watt scale in a frequency range between 215 GHz and 225 GHz based on these 1D models is demonstrated. The 3D PIC method is adopted to verify the theoretical design results, which shows that they are in good agreement with each other. Project supported by the Innovative Research Foundation of China Academy of Engineering Physics (Grant No. 426050502-2).

  5. Comparison of Stationarity Regions for Wireless Channels From 2 GHz to 30 GHz

    DEFF Research Database (Denmark)

    Yi, Tan; Wang, Chengxiang; Nielsen, Jesper Ødum

    2017-01-01

    and the channels below 6 GHz. First, the general average power delay profile (APDP) method is introduced as a metric to determine the size of the stationarity regions in time, frequency, and spatial domains. Then, the general APDP method is applied in the data analysis of a channel measurement. We find...

  6. An advanced real-time digital signal processing system for linear systems emulation, with special emphasis on network and acoustic response characterization

    Science.gov (United States)

    Gaydecki, Patrick; Fernandes, Bosco

    2003-11-01

    A fast digital signal processing (DSP) system is described that can perform real-time emulation of a wide variety of linear audio-bandwidth systems and networks, such as reverberant spaces, musical instrument bodies and very high order filter networks. The hardware design is based upon a Motorola DSP56309 operating at 110 million multiplication-accumulations per second and a dual-channel 24 bit codec with a maximum sampling frequency of 192 kHz. High level software has been developed to express complex vector frequency responses as both infinite impulse response (IIR) and finite impulse response (FIR) coefficients, in a form suitable for real-time convolution by the firmware installed in the DSP system memory. An algorithm has also been devised to express IIR filters as equivalent FIR structures, thereby obviating the potential instabilities associated with recursive equations and negating the traditional deficiencies of FIR filters respecting equivalent analogue designs. The speed and dynamic range of the system is such that, when sampling at 48 kHz, the frequency response can be specified to a spectral precision of 22 Hz when sampling at 10 kHz, this resolution increases to 0.9 Hz. Moreover, it is also possible to control the phase of any frequency band with a theoretical precision of 10-5 degrees in all cases. The system has been applied in the study of analogue filter networks, real-time Hilbert transformation, phase-shift systems and musical instrument body emulation, where it is providing valuable new insights into the understanding of psychoacoustic mechanisms.

  7. Chirped Pulse Spectrometer Operating at 200 GHz

    Science.gov (United States)

    Hindle, Francis; Bray, Cédric; Hickson, Kevin; Fontanari, Daniele; Mouelhi, Meriem; Cuisset, Arnaud; Mouret, Gaël; Bocquet, Robin

    2018-01-01

    The combination of electronic sources operating at high frequencies and modern microwave instrumentation has enabled the recent development of chirped pulse spectrometers for the millimetre and THz bands. This type of instrument can operate at high resolution which is particularly suited to gas-phase rotational spectroscopy. The construction of a chirped pulse spectrometer operating at 200 GHz is described in detail while attention is paid to the phase stability and the data accumulation over many cycles. Validation using carbonyl sulphide has allowed the detection limit of the instrument to be established as function of the accumulation. A large number of OCS transitions were identified using a 10-GHz chirped pulse and include the six most abundant isotopologues, the weakest line corresponding to the fundamental R(17) transition of 16O13C33S with a line strength of 4.3 × 10-26 cm-1/(molecule cm-2). The linearity of the system response for different degrees of data accumulation and transition line strength was confirmed over four orders of magnitudes. A simple analysis of the time-domain data was demonstrated to provide the line-broadening coefficient without the need for conversion by a Fourier transform. Finally, the pulse duration is discussed and optimal values are given for both Doppler-limited and collisional regimes.

  8. GHz-rate optical parametric amplifier in hydrogenated amorphous silicon

    International Nuclear Information System (INIS)

    Wang, Ke-Yao; Foster, Amy C

    2015-01-01

    We demonstrate optical parametric amplification operating at GHz-rates at telecommunications wavelengths using a hydrogenated amorphous silicon waveguide through the nonlinear optical process of four-wave mixing. We investigate how the parametric amplification scales with repetition rate. The ability to achieve amplification at GHz-repetition rates shows hydrogenated amorphous silicon’s potential for telecommunication applications and a GHz-rate optical parametric oscillator. (paper)

  9. On the performance of telemedicine system using 17-GHz orthogonally polarized microwave links under the influence of heavy rainfall.

    Science.gov (United States)

    Fong, Bernard; Fong, A C M; Hong, G Y

    2005-09-01

    This paper describes the design of a telemedicine system based on next-generation wireless local area networks (WLANs) operating at 17 GHz. Seventeen gigahertz is proposed for next-generation WLAN services offering numerous advantages over traditional IEEE 802.11 networks that operate in the range of 2.4-5 GHz. Orthogonal polarization is often used to increase spectrum efficiency by utilizing signal paths of horizontal and vertical polarization. Radio waves exceeding 10 GHz are particularly vulnerable to signal degradation under the influence of rain which causes an effective reduction in isolation between polarized signal paths. This paper investigates the influence of heavy rain in a tropical region on wide-band microwave signals at 17 GHz using two links provided by a fixed broad-band wireless access system for two-way data exchange between paramedics attending an accident scene and the hospital via microwave equipment installed in the ambulance. We also study the effects of cross polarization and phase rotation due to persistent heavy rainfall in tropical regions.

  10. Double dipole antenna SIS receivers at 100 and 400 GHz

    Science.gov (United States)

    Skalare, A.; Vandestadt, H.; Degraauw, T.; Panhuyzen, R. A.; Dierichs, M. M. T. M.

    1992-01-01

    Antenna patterns were measured between 95 and 120 GHz for a double dipole antenna / ellipsoidal lens combination. The structure produces a non-astigmatic beam with low side lobe levels over that whole band. A heterodyne SIS receiver based on this concept gave a best noise temperature of 145 K DSB at 98 GHz. Measurements were also made with a 400 GHz heterodyne SIS receiver, using a double dipole antenna in conjunction with a hyperhemispherical lens. The best noise temperature was 220 K DSB at 402 GHz. On-chip stubs were used to tune out the SIS junction capacitance.

  11. Multi-GHz Synchronous Waveform Acquisition With Real-Time Pattern-Matching Trigger Generation

    Science.gov (United States)

    Kleinfelder, Stuart A.; Chiang, Shiuh-hua Wood; Huang, Wei

    2013-10-01

    A transient waveform capture and digitization circuit with continuous synchronous 2-GHz sampling capability and real-time programmable windowed trigger generation has been fabricated and tested. Designed in 0.25 μm CMOS, the digitizer contains a circular array of 128 sample and hold circuits for continuous sample acquisition, and attains 2-GHz sample speeds with over 800-MHz analog bandwidth. Sample clock generation is synchronous, combining a phase-locked loop for high-speed clock generation and a high-speed fully-differential shift register for distributing clocks to all 128 sample circuits. Using two comparators per sample, the sampled voltage levels are compared against two reference levels, a high threshold and a low threshold, that are set via per-comparator digital to analog converters (DACs). The 256 per-comparator 5-bit DACs compensate for comparator offsets and allow for fine reference level adjustment. The comparator results are matched in 8-sample-wide windows against up to 72 programmable patterns in real time using an on-chip programmable logic array. Each 8-sample trigger window is equivalent to 4 ns of acquisition, overlapped sample by sample in a circular fashion through the entire 128-sample array. The 72 pattern-matching trigger criteria can be programmed to be any combination of High-above the high threshold, Low-below the low threshold, Middle-between the two thresholds, or “Don't Care”-any state is accepted. A trigger pattern of “HLHLHLHL,” for example, watches for a waveform that is oscillating at about 1 GHz given the 2-GHz sample rate. A trigger is flagged in under 20 ns if there is a match, after which sampling is stopped, and on-chip digitization can proceed via 128 parallel 10-bit converters, or off-chip conversion can proceed via an analog readout. The chip exceeds 11 bits of dynamic range, nets over 800-MHz -3-dB bandwidth in a realistic system, and jitter in the PLL-based sampling clock has been measured to be about 1 part

  12. Design and fabrication of a phononic-crystal-based Love wave resonator in GHz range

    Directory of Open Access Journals (Sweden)

    Ting-Wei Liu

    2014-12-01

    Full Text Available This paper presents a method for designing and fabricating a Love wave resonator utilizing the phononic crystal (PC as the reflectors. The PCs were formed by depositing 2D, periodically etched silica film on a quartz substrate. We analyzed the PC structure, and within its partial bandgap we designed a one-port resonator that contained a set of inter-digital transducer (IDT inside the resonant cavity bonded by two PC arrays. With sub-micrometer structures, the resonator was designed to operate at 1.25 GHz. The device was fabricated by employing the microelectromechanical system (MEMS fabrication technology and the resonant performance was evaluated.

  13. From analog to digital

    CERN Document Server

    Belleman, J

    2008-01-01

    Analog-to-digital conversion and its reverse, digital-to-analog conversion, are ubiquitous in all modern electronics, from instrumentation and telecommunication equipment to computers and entertainment. We shall explore the consequences of converting signals between the analog and digital domains and give an overview of the internal architecture and operation of a number of converter types. The importance of analog input and clock signal integrity will be explained and methods to prevent or mitigate the effects of interference will be shown. Examples will be drawn from several manufacturers' datasheets.

  14. Path Loss Validation for Urban Micro Cell Scenarios at 3.5 GHz Compared to 1.9 GHz

    DEFF Research Database (Denmark)

    Rodriguez, Ignacio; Nguyen, Huan Cong; Jørgensen, Niels T.K.

    2013-01-01

    The 3.5 GHz band is a strong candidate for future urban micro cell deployment with base station antennas located below rooftop. Compared to other frequency bands, propagation in the 3.5 GHz band is relatively unexplored for the micro cell deployment. This paper presents a measurement-based analysis......B higher for 3.5 GHz compared to 1.9 GHz. The outdoor-to-indoor propagation is investigated for two office buildings and different street shops. For the different presented scenarios, penetration loss increases with frequency and is found to be up to 5 dB higher for 3.5 GHz compared with 1.9 GHz. Although...... some existing models predict the observations with good accuracy, we propose a model based on line-of-sight probability that is simpler and easier to apply....

  15. 200-GHz and 50-GHz AWG channelized linewidth dependent transmission of weak-resonant-cavity FPLD injection-locked by spectrally sliced ASE.

    Science.gov (United States)

    Lin, Gong-Ru; Cheng, Tzu-Kang; Chi, Yu-Chieh; Lin, Gong-Cheng; Wang, Hai-Lin; Lin, Yi-Hong

    2009-09-28

    In a weak-resonant-cavity Fabry-Perot laser diode (WRC-FPLD) based DWDM-PON system with an array-waveguide-grating (AWG) channelized amplified spontaneous emission (ASE) source located at remote node, we study the effect of AWG filter bandwidth on the transmission performances of the 1.25-Gbit/s directly modulated WRC-FPLD transmitter under the AWG channelized ASE injection-locking. With AWG filters of two different channel spacings at 50 and 200 GHz, several characteristic parameters such as interfered reflection, relatively intensity noise, crosstalk reduction, side-mode-suppressing ratio and power penalty of BER effect of the WRC-FPLD transmitted data are compared. The 200-GHz AWG filtered ASE injection minimizes the noises of WRC-FPLD based ONU transmitter, improving the power penalty of upstream data by -1.6 dB at BER of 10(-12). In contrast, the 50-GHz AWG channelized ASE injection fails to promote better BER but increases the power penalty by + 1.5 dB under back-to-back transmission. A theoretical modeling elucidates that the BER degradation up to 4 orders of magnitude between two injection cases is mainly attributed to the reduction on ASE injection linewidth, since which concurrently degrades the signal-to-noise and extinction ratios of the transmitted data stream.

  16. The effect of a 94 GHz electromagnetic field on neuronal microtubules.

    Science.gov (United States)

    Samsonov, Andrey; Popov, Sergey V

    2013-02-01

    Hardware that generates electromagnetic waves with wavelengths from 1 to 10 mm (millimeter waves, "MMW") is being used in a variety of applications, including high-speed data communication and medical devices. This raises both practical and fundamental issues concerning the interaction of MMW electromagnetic fields (EMF) with biological tissues. A 94 GHz EMF is of particular interest because a number of applications, such as active denial systems, rely on this specific frequency. Most of the energy associated with MMW radiation is absorbed in the skin and, for a 94 GHz field, the power penetration depth is shallow (≈0.4 mm). At sufficiently high energies, skin heating is expected to activate thermal pain receptors, leading to the perception of pain. In addition to this "thermal" mechanism of action, a number of "non-thermal" effects of MMW fields have been previously reported. Here, we investigated the influence of a 94 GHz EMF on the assembly/disassembly of neuronal microtubules in Xenopus spinal cord neurons. We reasoned that since microtubule array is regulated by a large number of intracellular signaling cascades, it may serve as an exquisitely sensitive reporter for the biochemical status of neuronal cytoplasm. We found that exposure to 94 GHz radiation increases the rate of microtubule assembly and that this effect can be entirely accounted for by the rapid EMF-elicited temperature jump. Our data are consistent with the notion that the cellular effects of a 94 GHz EMF are mediated entirely by cell heating. Copyright © 2012 Wiley Periodicals, Inc.

  17. Direct satellite TV - The 12-GHz challenge

    Science.gov (United States)

    Fawcette, J.

    1982-02-01

    Manufacturers in Japan and Europe are developing the hardware necessary for commercially feasible direct broadcast satellite TV, including high-frequency circuits and mini-dishes for spacecasting. US companies are lagging behind due to formidable regulatory and legal difficulties. The article focuses on efforts to develop simple, inexpensive receivers which will be able to convert 12-GHz satellite transmissions into high-quality TV images. Three basic receiver designs are being developed: the mixer-downcaster, microwave integrated circuits using FET-preamplifier front ends with transistors connected by bond-wires, and monolithic gallium arsenide integrated circuits. Several companies are on the verge of introducing commercialized receivers utilizing these different basic designs.

  18. Practical digital electronics for technicians

    CERN Document Server

    Kimber, Will

    2013-01-01

    Practical Digital Electronics for Technicians covers topics on analog and digital signals, logic gates, combinational logic, and Karnaugh mapping. The book discusses the characteristics and types of logic families; sequential systems including latch, bistable circuits, counters and shift registers; Schmitt triggers and multivibrators; and MSI combinational logic systems. Display devices, including LED, LCD and dot matrix display; analog and digital conversion; and examples of and equipment for digital fault finding are also considered. The book concludes by providing answers to the questions

  19. Digital setup for Doppler broadening spectroscopy

    International Nuclear Information System (INIS)

    Cizek, J; Vlcek, M; Prochazka, I

    2011-01-01

    New digital spectrometer for measurement of the Doppler shift of annihilation photons was developed and tested in this work. Digital spectrometer uses a fast 12-bit digitizer for direct sampling of signals from HPGe detectors. Analysis of sampled waveforms is performed off-line in software. Performance of the new digital setup was compared with its traditional analogue counterpart. Superior energy resolution was achieved in the digital setup. Moreover, the digital setup allows for a better control of the shape of detector signals. This enables to eliminate undesired signals damaged by pile-up effects or by ballistic deficit.

  20. Handoff Management in Radio over Fiber 60 GHz Indoor Networks

    NARCIS (Netherlands)

    Bien, V.Q.

    2014-01-01

    Because of high data rate multimedia applications such as HD and UHDTV, online games, etc., the future home networks are expected to support short-range gigabit transmission. With the worldwide availability of 5 GHz spectrum at the 60 GHz band, it creates the opportunity for a promising air