WorldWideScience

Sample records for communication system combined

  1. Virtualization of Wireless Communication Systems and Its Maximal Ratio Combining Macrodiversity To Extend CDMA Capacity

    Institute of Scientific and Technical Information of China (English)

    王际兵; 赵明; 周世东; 姚彦

    2001-01-01

    The concept of virtualization of wireless communication systemsis based on the open and scalable hardware platform of software radios in the personal communication network. The base station is divided into four components according to their functions: antenna, IF, baseband, and control, which are connected by the ATM network. Virtualization provides great benefits such as fast handoff and easy realization of different macrodiversity algorithms. Macrodiversity can not be easily realized in conventional cellular systems. An exact analysis is presented for the performance of maximal ratio combining (MRC) macrodiversity in virtualized wireless communication systems. The results show that compared with soft handoff in CDMA systems, MRC can greatly increase the reverse link capacity.

  2. A robust and scalable neuromorphic communication system by combining synaptic time multiplexing and MIMO-OFDM.

    Science.gov (United States)

    Srinivasa, Narayan; Zhang, Deying; Grigorian, Beayna

    2014-03-01

    This paper describes a novel architecture for enabling robust and efficient neuromorphic communication. The architecture combines two concepts: 1) synaptic time multiplexing (STM) that trades space for speed of processing to create an intragroup communication approach that is firing rate independent and offers more flexibility in connectivity than cross-bar architectures and 2) a wired multiple input multiple output (MIMO) communication with orthogonal frequency division multiplexing (OFDM) techniques to enable a robust and efficient intergroup communication for neuromorphic systems. The MIMO-OFDM concept for the proposed architecture was analyzed by simulating large-scale spiking neural network architecture. Analysis shows that the neuromorphic system with MIMO-OFDM exhibits robust and efficient communication while operating in real time with a high bit rate. Through combining STM with MIMO-OFDM techniques, the resulting system offers a flexible and scalable connectivity as well as a power and area efficient solution for the implementation of very large-scale spiking neural architectures in hardware.

  3. Combined Resource Allocation System for Device-to-Device Communication towards LTE Networks

    Directory of Open Access Journals (Sweden)

    Abbas Fakhar

    2016-01-01

    Full Text Available The LTE networks are being developed to grant mobile broadband services in the fourth generation (4G systems and allow operators to use spectrum more efficiently.D2D communication is a promising technique to provide wireless services and enhance spectrum exploitation in the LTE Heterogeneous Networks (HetNets.D2D communication in HetNets allows users to communicate with each other directly by reusing the resources when communicating via the base stations. But during the downlink period, both the D2D receiver and the Heterogeneous Users equipment’s (HUE experience interference caused by resource allocation. In this article, we identify and analyze the interference problem of HetNets caused by D2D transmitter during download. We propose a combined resource allocation and resource reuse method for LTE HetNets, where resource allocation to HUEs is employed on the basis of comparative fair algorithm and resource reuse to D2D users is employed on acquisitive empirical algorithm. This approach evaluates whether D2D mode is suitable or not by path loss evaluation, after that decreases the interference to HUE by selection of the minimum channel gain between HUE and D2D transmitter each time to mitigate interference. Our simulation results show that the efficiency and throughput of HetNets is improved by using the proposed method.

  4. Performance improvement of OFDM-FSO multi-user communication system with combined transmit frequency diversity and receive space diversity

    Science.gov (United States)

    Kumar, Pravindra; Srivastava, Anand

    2016-05-01

    Orthogonal frequency division multiplexed (OFDM) based free space optical (FSO) communication link gives improved performance because of narrow-band interference, improved robustness against fading and high bandwidth efficiency. It is further improved using transmit frequency diversity and space diversity at the receiver. In this paper, we propose to use OFDM architecture combined with spreading code in electrical domain, referred as code division multiplexed-orthogonal frequency division multiplexing (CDM-OFDM) which provides frequency diversity at the transmitter and using more than one receiver to get receive diversity. Analytical model of CDM-OFDM-FSO communication system with photo-detector space diversity using maximal ratio combining (MRC) is analyzed in the presence of turbulent atmosphere, multi-user-interference (MUI) and timing jitter. The error performance is computed in terms of receiver sensitivity and bit-error-rate (BER). In the analysis, Gamma-Gamma distribution is considered for atmospheric turbulence. The performance of OFDM-FSO link and CDM-OFDM-FSO link is compared. It is seen that for multiple users, CDM-OFDM-FSO link with transmit and receive diversity gives improved performance as compared to OFDM-FSO link.

  5. Introduction to digital communication systems

    CERN Document Server

    Wesolowski, Krzysztof

    2009-01-01

    Combining theoretical knowledge and practical applications, this advanced-level textbook covers the most important aspects of contemporary digital communication systems. Introduction to Digital Communication Systems focuses on the rules of functioning digital communication system blocks, starting with the performance limits set by the information theory. Drawing on information relating to turbo codes and LDPC codes, the text presents the basic methods of error correction and detection, followed by baseband transmission methods, and single- and multi-carrier digital modulations. The basi

  6. Communication System and Method

    Science.gov (United States)

    Sanders, Adam M. (Inventor); Strawser, Philip A. (Inventor)

    2014-01-01

    A communication system for communicating over high-latency, low bandwidth networks includes a communications processor configured to receive a collection of data from a local system, and a transceiver in communication with the communications processor. The transceiver is configured to transmit and receive data over a network according to a plurality of communication parameters. The communications processor is configured to divide the collection of data into a plurality of data streams; assign a priority level to each of the respective data streams, where the priority level reflects the criticality of the respective data stream; and modify a communication parameter of at least one of the plurality of data streams according to the priority of the at least one data stream.

  7. Advanced quantum communication systems

    Science.gov (United States)

    Jeffrey, Evan Robert

    Quantum communication provides several examples of communication protocols which cannot be implemented securely using only classical communication. Currently, the most widely known of these is quantum cryptography, which allows secure key exchange between parties sharing a quantum channel subject to an eavesdropper. This thesis explores and extends the realm of quantum communication. Two new quantum communication protocols are described. The first is a new form of quantum cryptography---relativistic quantum cryptography---which increases communication efficiency by exploiting a relativistic bound on the power of an eavesdropper, in addition to the usual quantum mechanical restrictions intrinsic to quantum cryptography. By doing so, we have observed over 170% improvement in communication efficiency over a similar protocol not utilizing relativity. A second protocol, Quantum Orienteering, allows two cooperating parties to communicate a specific direction in space. This application shows the possibility of using joint measurements, or projections onto an entangled state, in order to extract the maximum useful information from quantum bits. For two-qubit communication, the maximal fidelity of communication using only separable operations is 73.6%, while joint measurements can improve the efficiency to 78.9%. In addition to implementing these protocols, we have improved several resources for quantum communication and quantum computing. Specifically, we have developed improved sources of polarization-entangled photons, a low-loss quantum memory for polarization qubits, and a quantum random number generator. These tools may be applied to a wide variety of future quantum and classical information systems.

  8. Power Electronics System Communications

    OpenAIRE

    Milosavljevic, Ivana

    1999-01-01

    This work investigates communication issues in high-frequency power converters. A novel control communication network (Power Electronics System Network or PES Net) is proposed for modular, medium and high-power, converters. The network protocol, hardware and software are designed and implemented. The PES Net runs at 125 Mb/s over plastic optical fiber allowing converter switching frequencies in excess of 100 kHz. Communication control is implemented in a fie...

  9. Communication system for emergency

    Energy Technology Data Exchange (ETDEWEB)

    Ajioka, Yoshiteru [Shizuoka Prefecture (Japan)

    1996-12-01

    People are apprehensive that a strong earthquake with a magnitude of nearly 8 may occur in Tokai area. The whole area of Shizuoka Prefecture has been specified as the specially strengthened region for earthquake disaster measures. This report outlines the communication system for emergency with respect to atomic disaster caused by an earthquake. Previously, wireless receiving system is stationed in the whole area to simultaneously inform the related news to the residents and so, communications with them are possible at any time by using the system. Since mobile wireless receiving sets are stationed in all town halls, self defense organizations and all the places of refuge, mutual communications are possible. These communication system can be utilized for either earthquake or nuclear disaster. Further, Shizuoka general information network system has been established as a communication system for anti-disaster organization and a wireless network via a communication satellite, ``super bird`` has been constructed in addition to the ground network. Therefore, the two communication routes became usable at emergency and the systems are available in either of nuclear disaster or earthquake. (M.N.)

  10. Combining a Multi-Agent System and Communication Middleware for Smart Home Control: A Universal Control Platform Architecture

    Directory of Open Access Journals (Sweden)

    Song Zheng

    2017-09-01

    Full Text Available In recent years, the smart home field has gained wide attention for its broad application prospects. However, families using smart home systems must usually adopt various heterogeneous smart devices, including sensors and devices, which makes it more difficult to manage and control their home system. How to design a unified control platform to deal with the collaborative control problem of heterogeneous smart devices is one of the greatest challenges in the current smart home field. The main contribution of this paper is to propose a universal smart home control platform architecture (IAPhome based on a multi-agent system and communication middleware, which shows significant adaptability and advantages in many aspects, including heterogeneous devices connectivity, collaborative control, human-computer interaction and user self-management. The communication middleware is an important foundation to design and implement this architecture which makes it possible to integrate heterogeneous smart devices in a flexible way. A concrete method of applying the multi-agent software technique to solve the integrated control problem of the smart home system is also presented. The proposed platform architecture has been tested in a real smart home environment, and the results indicate that the effectiveness of our approach for solving the collaborative control problem of different smart devices.

  11. AMPA experimental communications systems

    Science.gov (United States)

    Beckerman, D.; Fass, S.; Keon, T.; Sielman, P.

    1982-01-01

    The program was conducted to demonstrate the satellite communication advantages of Adaptive Phased Array Technology. A laboratory based experiment was designed and implemented to demonstrate a low earth orbit satellite communications system. Using a 32 element, L-band phased array augmented with 4 sets of weights (2 for reception and 2 for transmission) a high speed digital processing system and operating against multiple user terminals and interferers, the AMPA system demonstrated: communications with austere user terminals, frequency reuse, communications in the face of interference, and geolocation. The program and experiment objectives are described, the system hardware and software/firmware are defined, and the test performed and the resultant test data are presented.

  12. Digital communication system

    Science.gov (United States)

    Monford, L. G., Jr. (Inventor)

    1974-01-01

    A digital communication system is reported for parallel operation of 16 or more transceiver units with the use of only four interconnecting wires. A remote synchronization circuit produces unit address control words sequentially in data frames of 16 words. Means are provided in each transceiver unit to decode calling signals and to transmit calling and data signals. The transceivers communicate with each other over one data line. The synchronization unit communicates the address control information to the transceiver units over an address line and further provides the timing information over a clock line. A reference voltage level or ground line completes the interconnecting four wire hookup.

  13. Combined GMSK Communications and PN Ranging

    Science.gov (United States)

    Orr, Richard; Divsalar, Dariush

    2008-01-01

    A document discusses a method by which GMSK (Gaussian minimum shift keying) modulation and a pseudonoise (PN) ranging signal may be combined. By isolating the in-phase and quadrature components after carrier lock, and extracting their low-pass and band-pass filtered components, there is enough information available to both demodulate data and track the PN signal. The proposed combined GMSK communications and PN ranging is one potential approach to address emerging requirements for simultaneous high data rate communications from and tracking of vehicles in deep space or at the Moon.

  14. The Evolution of Communication Systems

    OpenAIRE

    2010-01-01

    One can study communications by using Shannon's (1948) mathematical theory of communication. In social communications, however, the channels are not "fixed", but themselves subject to change. Communication systems change by communicating information to related communication systems; co-variation among systems if repeated over time, can lead to co-evolution. Conditions for stabilization of higher-order systems are specifiable: segmentation, stratification, differentiation, reflection, and self...

  15. Combining analytic and experiential communication in participatory scenario development

    NARCIS (Netherlands)

    Vervoort, J.M.; Kok, K.; Beers, P.J.; Lammeren, van R.J.A.; Janssen, R.

    2012-01-01

    This paper explores the need to combine analytic understanding and experiential engagement in communication on social–ecological systems futures. Humans use two distinct mental modes to deal with salient information: analytic processing and experiential processing. Tools combining both modes of proc

  16. DYMAC communications system

    Energy Technology Data Exchange (ETDEWEB)

    Lindsey, K.A.

    1980-01-01

    The DYMAC Communications System is part of a nuclear safeguards system called DYMAC - short for DYnamic Materials ACcountability - that gathers accountability information at the Los Alamos Scientific Laboratory (LASL) Plutonium Processing Facility. The communications system handles transmissions between data-entry terminals and nondestructive assay (NDA) instruments located in the facility, and a computer located in an adjacent building. System design emphasizes reliability rather than high speed to ensure the integrity of data transmissions. This manual is directed toward the person responsible for maintaining the DYMAC Communication System. It describes the components that make up the communications network, explains how they operate, and gives detailed information about all of the connections. Many of the system components are commercially available; some have been modified at LASL for DYMAC purposes; others were designed and fabricated at LASL. This manual provides circuit diagrams for all of the LASL modifications and LASL-fabricated equipment. In addition, it provides a series of procedures for tracing cables, reconfiguring various parts of the system, testing data transmissions, and troubleshooting malfunctions.

  17. Airborne wireless communication systems, airborne communication methods, and communication methods

    Science.gov (United States)

    Deaton, Juan D [Menan, ID; Schmitt, Michael J [Idaho Falls, ID; Jones, Warren F [Idaho Falls, ID

    2011-12-13

    An airborne wireless communication system includes circuitry configured to access information describing a configuration of a terrestrial wireless communication base station that has become disabled. The terrestrial base station is configured to implement wireless communication between wireless devices located within a geographical area and a network when the terrestrial base station is not disabled. The circuitry is further configured, based on the information, to configure the airborne station to have the configuration of the terrestrial base station. An airborne communication method includes answering a 911 call from a terrestrial cellular wireless phone using an airborne wireless communication system.

  18. Distribution system protection with communication technologies

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    2010-01-01

    Due to the communication technologies’ involvement in the distribution power system, the time-critical protection function may be implemented more accurately, therefore distribution power systems’ stability, reliability and security could be improved. This paper presents an active distribution...... power system, including CHPs (Combined Heating and Power) and small scaled WTs (Wind Turbines), as a practical example to examine the possible impacts of communication technologies on the power system. Under some fault scenarios, the power system’s responses to the fault are compared between the system...... with communication technologies and that without communication technologies. At the same time, the previously proposed study method of combining the simulations of communication and power systems is adopted in this study. The performance of a communication network adopted for power system is simulated by OPNET...

  19. Communication Facilities for Distributed Systems

    Directory of Open Access Journals (Sweden)

    V. Barladeanu

    1997-01-01

    Full Text Available The design of physical networks and communication protocols in Distributed Systems can have a direct impact on system efficiency and reliability. This paper tries to identify efficient mechanisms and paradigms for communication in distributed systems.

  20. Combination of spatial diversity and parallel decision feedback equalizer in a Single Input Multiple Output underwater acoustic communication system operating at very high frequencies

    Science.gov (United States)

    Skoro Kaskarovska, Violeta; Beaujean, Pierre-Philippe

    2013-05-01

    Single Input Multiple Output (SIMO) acoustic communication system using an adaptive spatial diversity combined with parallel Decision Feedback Equalizer (DFE) is presented in this document. The SIMO system operates at high frequencies with high data rate over a limited range (less than 200 m) in very shallow waters. The SIMO system consists of a single source transmitting Phase Shift Keying (PSK) messages modulated at 300 kHz and received by multiple receivers. In a first configuration, the symbols collected at each receiver are equalized using a decision feedback equalizer and combined using Maximum Ratio Combining (MRC). In a second configuration, the MRC outputs are used as decision symbols in the DFE. This second configuration is a form of turbo equalization: the process can be repeated over and over, leading to a better estimate of the received message as the number of iterations increases. The adaptive process of diversity is repeated until the best possible result is achieved or a predefined error criterion is met. Bit Error Rate (BER) and Signal-to-Noise-and-Interference Ratio (SNIR) are used as performance metrics of the acoustic channel. Experimental results using SIMO system with three, four or five receivers and pre-processed real recorded data demonstrate ability to improve the performance of the acoustic channel in challenging environments. Using received messages with non-zero BER, adaptive spatial diversity can achieve BER of 0% and increased SNIR of 3 dB with number of iterations depending on the number of receivers used.

  1. Field application. Selective stimulation of reservoirs or perforated intervals with use of coiled tubing equipped with real-time data communication system in combination with straddle packer assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Oberascher, R.; Breimer, G. [GDF SUEZ E and P Deutschland GmbH, Lingen (Germany); Jonge, R.M. de [Baker Hughes (Netherlands)

    2013-08-01

    In two German gas wells a decline in production and wellhead pressures had been observed. Production logging data obtained by PLT surveys were evaluated, which showed that certain intervals within the reservoir section did not contribute, or showed a restricted contribution to the overall gas production. The restricted contribution was suspected to be caused by near-wellbore damage. To restore or enhance the production of the perforated intervals an acid treatment was considered in these wells in order to remove skin damage. To restore or enhance the production of the wells, an acid treatment of the perforated intervals was designed. For obtaining the required selective placement of the acid across the zones of interest, the use of coiled tubing (CT) in combination with a resettable straddle packer assembly was selected. The accuracy of the setting depth of the straddle packer was a critical issue for the execution of the well intervention operations. In order to obtain the required depth accuracy, the CT string was equipped with an intelligent CT communication system, which transfers real-time downhole data to surface. For the first time, a reservoir stimulation project was executed by combining CT equipped with a real-time data communication system (TeleCoil) and the Inflatable Straddle Acidizing Packer (ISAP) assembly. Inside the CT an encapsulated monoconductor cable was installed to transmit real-time data from the CT Bottom Hole Assembly (BHA) to surface. The BHA consists of a Casing Collar Locator (CCL) and downhole pressure and temperature gauges. Due to the protective jacket of the monoconductor cable, there are no restrictions in the use of different fluids in combination with the system. Information provided by the CCL monitoring tool ensures accurate depth correlations, whereas differential pressure measurements from the down-hole pressure gauges provide positive information about the setting and sealing conditions of the straddle packer assembly. The

  2. 基于联合混沌系统的保密通信方法研究%Study for Secure Communications Based on Combined Discrete Chaotic Systems

    Institute of Scientific and Technical Information of China (English)

    王兆霞; 陈增强; 袁著祉; 郝庭柱; 杨保和

    2002-01-01

    We presents an approach for secure communication by using combined discrete chaotic systems.Two well-known chaotic systems,Henon and Lorenz are combined as an illustrative example to demonstrate the effectiveness of the proposed approach.The chaotic systems adopt backstepping design an dead-beat synchronization scheme because of the characteristics that can reach to synchronization quickly.Simple chaotic masking technique is used in the simulation.The results as well as the theory analysis show that the proposed method is feasible and is of more security performance compared to the non-combined chaotic systems.The proposed scheme is not only can be carried out easily and easy to control,but also advances the security performance of whole system.%提出了利用离散混沌系统联合加密来实现保密通信的方法.引用了著名的Henon和Lorenz混沌系统作为仿真实验证明了其可行性,混沌系统均采用backstepping和dead-beat同步设计方案,以快速达到同步.理论分析证明,此种方法不仅是可行的,且与非联合混沌系统相比,加强了保密性.混沌屏蔽技术仿真结果也证明,该系统不仅实现简单,容易控制,而且增强了整个系统的保密性能.

  3. Digital and analog communication systems

    Science.gov (United States)

    Shanmugam, K. S.

    1979-01-01

    The book presents an introductory treatment of digital and analog communication systems with emphasis on digital systems. Attention is given to the following topics: systems and signal analysis, random signal theory, information and channel capacity, baseband data transmission, analog signal transmission, noise in analog communication systems, digital carrier modulation schemes, error control coding, and the digital transmission of analog signals.

  4. COMMUNICATIONS AND INFORMATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Dănuţ ŢIGĂNUŞ

    2011-01-01

    Full Text Available This essay assesses the communications and information systems (CIS in support of the civilian and military structures deployed in the European Union led crises management operations and missions. The article emphasizes the specific structure and function of CIS taking in consideration the particularities of EU led missions. The integration of the EU institutional networks and systems with the national systems provided by the EU member states is considered a key element. The analysis-part of this paper starts with the specific EU command and control system for crises management missions based on two autonomous solutions and one relying on NATO capabilities. Further, it continues with the challenges of the classifi ed information exchange at the operational theatre level. The most important contribution of this article is based on the long term vision implementation measures for the CIS structure, roles, functions and services provided and the information management infrastructure. CIS deployment mechanisms are described with references to the practical situation of the CIS deployed in support of crises management operations and missions. Two important defi nitions are provided regarding the CIS for crisis management and their roles in the specific EU operational environment. The system view of the operational CIS is depicted and analysed also, with a focus on the integration aspects of the infrastructure as the information transport layer for the information exchange flow. The last part of the article focuses on the CIS functions for the deployed systems which are detailed alongside with the C2 and Information Exchange Requirements in the EU operational environment. The variety of the theoretical approaches to determine the CIS infrastructure for EU-led civilian and military missions triggers the conclusion that the planning and implementation process is extremely complex especially in the context of the new security environment and requires

  5. Communication Systems Analysis Laboratory (CSAL)

    Data.gov (United States)

    Federal Laboratory Consortium — CSAL conducts electronic warfare investigations of radio frequency communication systems with respect to current and emerging electronic warfare threats. CSAL uses...

  6. Wavelet transform domain communication systems

    Science.gov (United States)

    Orr, Richard S.; Pike, Cameron; Lyall, Michael J.

    1995-04-01

    In this paper we introduce a new class of communications systems called wavelet transform domain (WTD) systems. WTD systems are transmultiplexer (TMUX) structures in which information to be communicated over a channel is encoded, via an inverse discrete wavelet transform (IDWT), as the wavelet coefficients of the transmitted signal, and extracted at the receiver by a discrete wavelet transform (DWT). WTD constructs can be used for covert, or low probability of intercept/detection (LPI/D) communications, baseband bandwidth efficient communications, or code-division multiple access (CDMA). This paper concentrates on the spread spectrum applications.

  7. Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture

    Science.gov (United States)

    Steele, Kerry D [Kennewick, WA; Anderson, Gordon A [Benton City, WA; Gilbert, Ronald W [Morgan Hill, CA

    2011-02-01

    Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture are described. In one aspect, a communications device identification method includes providing identification information regarding a group of wireless identification devices within a wireless communications range of a reader, using the provided identification information, selecting one of a plurality of different search procedures for identifying unidentified ones of the wireless identification devices within the wireless communications range, and identifying at least some of the unidentified ones of the wireless identification devices using the selected one of the search procedures.

  8. Underwater wireless communication system

    Energy Technology Data Exchange (ETDEWEB)

    Goh, J H; Shaw, A; Al-Shamma' a, A I, E-mail: j.h.goh@2006.ljmu.ac.u [Liverpool John Moores University, General Engineering Research Institute (GERI), RF and Microwave Group, Byrom Street, Liverpool, L3 3AF (United Kingdom)

    2009-07-01

    Underwater communication has a range of applications including remotely operated vehicle (ROV) and autonomous underwater vehicle (AUV) communication and docking in the offshore industry. Current underwater transmission techniques is primarily utilise sound waves for large distance at lower frequencies and the velocity of sound in water is approximately 1500m/s the resultant communications have problems with multi-path propagation and low bandwidth problems. The use of electromagnetic (EM) techniques underwater has largely been overlooked because of the attenuation due to the conductivity of seawater. However, for short range applications, the higher frequencies and much higher velocity can prove advantageous. This paper will outline a project which will utilise recent investigations that demonstrate EM wave propagation up to the MHz frequency range is possible in seawater.

  9. On Building Secure Communication Systems

    DEFF Research Database (Denmark)

    Carvalho Quaresma, Jose Nuno

    This thesis presents the Guided System Development (GSD) framework, which aims at supporting the development of secure communication systems. A communication system is specified in a language similar to the Alice and Bob notation, a simple and intuitive language used to describe the global...... perspective of the communications between different principals. The notation used in the GSD framework extends that notation with constructs that allow the security requirements of the messages to be described. From that specification, the developer is guided through a semi-automatic translation that enables...... into code that implements the communication skeleton of the system and can then be used by the system designer. New output languages can also easily be added to the GSD framework. Additionally, a prototype of the GSD framework was implemented and an ex-ample of using the GSD framework in a real world system...

  10. Communication, Work Systems and HRD

    Science.gov (United States)

    Pace, R. Wayne

    2013-01-01

    Purpose: The purpose of this article is to show the foundational place that communication theory and its practice occupies in functioning work systems. Design/methodology/approach: This paper defines the word communication in terms of the creation and interpretation of displays, describes what it means to have a theoretical foundation for a…

  11. Multiantenna systems for MIMO communications

    CERN Document Server

    DeFlaviis, Franco

    2008-01-01

    Advanced communication scenarios demand the development of new systemswhere antenna theory, channel propagation and communication models are seen from a common perspective as a way to understand and optimize the system as a whole. In this context, a comprehensive multiantenna formulation for multiple-input multiple-output systems is presented with a special emphasis on the connection of the electromagnetic and communication principles.Starting from the capacity for amultiantenna system, the book reviews radiation, propagation, and communicationmechanisms, paying particular attention to the vec

  12. Quantum Communication Systems

    Science.gov (United States)

    2008-03-15

    Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39-18 Publications: 1) W. Wasilewski and...K. Banaszek, Protecting an optical qubit against photon loss, Phys. Rev. A 75, 042316 (2007) 2) K. Banaszek and W. Wasilewski , Linear-optics...manipulations of photon-loss codes, Proceedings of NATO Advanced Research Workshop "Quantum Communication and Security" 3) W. Wasilewski , P. Kolenderski

  13. 49 CFR 193.2519 - Communication systems.

    Science.gov (United States)

    2010-10-01

    ... primary communication system that provides for verbal communications between all operating personnel at...) storage capacity must have an emergency communication system that provides for verbal communications... 49 Transportation 3 2010-10-01 2010-10-01 false Communication systems. 193.2519 Section 193.2519...

  14. Communicating embedded systems networks applications

    CERN Document Server

    Krief, Francine

    2013-01-01

    Embedded systems become more and more complex and require having some knowledge in various disciplines such as electronics, data processing, telecommunications and networks. Without detailing all the aspects related to the design of embedded systems, this book, which was written by specialists in electronics, data processing and telecommunications and networks, gives an interesting point of view of communication techniques and problems in embedded systems. This choice is easily justified by the fact that embedded systems are today massively communicating and that telecommunications and network

  15. Advanced satellite communication system

    Science.gov (United States)

    Staples, Edward J.; Lie, Sen

    1992-01-01

    The objective of this research program was to develop an innovative advanced satellite receiver/demodulator utilizing surface acoustic wave (SAW) chirp transform processor and coherent BPSK demodulation. The algorithm of this SAW chirp Fourier transformer is of the Convolve - Multiply - Convolve (CMC) type, utilizing off-the-shelf reflective array compressor (RAC) chirp filters. This satellite receiver, if fully developed, was intended to be used as an on-board multichannel communications repeater. The Advanced Communications Receiver consists of four units: (1) CMC processor, (2) single sideband modulator, (3) demodulator, and (4) chirp waveform generator and individual channel processors. The input signal is composed of multiple user transmission frequencies operating independently from remotely located ground terminals. This signal is Fourier transformed by the CMC Processor into a unique time slot for each user frequency. The CMC processor is driven by a waveform generator through a single sideband (SSB) modulator. The output of the coherent demodulator is composed of positive and negative pulses, which are the envelopes of the chirp transform processor output. These pulses correspond to the data symbols. Following the demodulator, a logic circuit reconstructs the pulses into data, which are subsequently differentially decoded to form the transmitted data. The coherent demodulation and detection of BPSK signals derived from a CMC chirp transform processor were experimentally demonstrated and bit error rate (BER) testing was performed. To assess the feasibility of such advanced receiver, the results were compared with the theoretical analysis and plotted for an average BER as a function of signal-to-noise ratio. Another goal of this SBIR program was the development of a commercial product. The commercial product developed was an arbitrary waveform generator. The successful sales have begun with the delivery of the first arbitrary waveform generator.

  16. Compressive Sensing in Communication Systems

    DEFF Research Database (Denmark)

    Fyhn, Karsten

    2013-01-01

    Wireless communication is omnipresent today, but this development has led to frequency spectrum becoming a limited resource. Furthermore, wireless devices become more and more energy-limited, due to the demand for continual wireless communication of higher and higher amounts of information....... The need for cheaper, smarter and more energy efficient wireless devices is greater now than ever. This thesis addresses this problem and concerns the application of the recently developed sampling theory of compressive sensing in communication systems. Compressive sensing is the merging of signal...... acquisition and compression. It allows for sampling a signal with a rate below the bound dictated by the celebrated Shannon-Nyquist sampling theorem. In some communication systems this necessary minimum sample rate, dictated by the Shannon-Nyquist sampling theorem, is so high it is at the limit of what...

  17. EMI protection for communication systems

    CERN Document Server

    Malaric, Kresimir

    2009-01-01

    This practical reference provides a thorough understanding of how to protect communication systems from intentional and unintentional electromagnetic interference. You learn how to overcome critical problems in both digital and analog communications. This unique resource shows you how to shield equipment from electrical and magnetic fields, design TEM and GTEM-Cell, build capacitive coupling clamps for susceptibility tests, protect electronic equipment with filters, and calculate the measurement uncertainty. You find numerous, well-illustrated examples that make challenging electromagnetics is

  18. Safety and communication, a winning combination

    CERN Multimedia

    HSE Unit

    2014-01-01

    Since 2013, in line with its mission to support CERN’s proactive communication policy in matters of safety, the HSE unit has been following an annual plan for disseminating information on occupational health and safety and environmental protection.   Safety information designed to underline the importance of prevention is published through a variety of channels: Announcements in the CERN Bulletin, Safety bulletins, notably outlining lessons to be learned in the wake of accidents/incidents occuring at CERN, Safety alerts calling for immediate action, sent by e-mail to the services concerned, Prevention campaigns on the CERN site, Poster campaigns in well frequented public areas. Photo: Christoph Balle. Please heed all prevention messages and apply them in your everyday life. Also, we will be pleased to receive any information or suggestions you may have on safety matters. If you have questions about the HSE unit’s communication activities, please send us an e...

  19. Mobile Communication Systems and Security

    CERN Document Server

    Rhee, Man Young

    2009-01-01

    Mobile Communication Systems and Security arms readers with a thorough understanding of all major cellular air-interface technologies and their security layer techniques. Rhee covers the technological development of wireless mobile communications in compliance with each iterative generation up to 3G systems and beyond, with an emphasis on wireless security aspects. By progressing in a systematic manner, presenting the theory and practice of wireless mobile technologies along with various security problems, readers will gain an intimate sense of how mobile systems operate and how to address com

  20. Fiber-optic communication systems

    CERN Document Server

    Agrawal, Govind P

    2010-01-01

    This book provides a comprehensive account of fiber-optic communication systems. The 3rd edition of this book is used worldwide as a textbook in many universities. This 4th edition incorporates recent advances that have occurred, in particular two new chapters. One deals with the advanced modulation formats (such as DPSK, QPSK, and QAM) that are increasingly being used for improving spectral efficiency of WDM lightwave systems. The second chapter focuses on new techniques such as all-optical regeneration that are under development and likely to be used in future communication systems. All othe

  1. A Model of Internal Communication in Adaptive Communication Systems.

    Science.gov (United States)

    Williams, M. Lee

    A study identified and categorized different types of internal communication systems and developed an applied model of internal communication in adaptive organizational systems. Twenty-one large organizations were selected for their varied missions and diverse approaches to managing internal communication. Individual face-to-face or telephone…

  2. A systems approach to animal communication.

    Science.gov (United States)

    Hebets, Eileen A; Barron, Andrew B; Balakrishnan, Christopher N; Hauber, Mark E; Mason, Paul H; Hoke, Kim L

    2016-03-16

    Why animal communication displays are so complex and how they have evolved are active foci of research with a long and rich history. Progress towards an evolutionary analysis of signal complexity, however, has been constrained by a lack of hypotheses to explain similarities and/or differences in signalling systems across taxa. To address this, we advocate incorporating a systems approach into studies of animal communication--an approach that includes comprehensive experimental designs and data collection in combination with the implementation of systems concepts and tools. A systems approach evaluates overall display architecture, including how components interact to alter function, and how function varies in different states of the system. We provide a brief overview of the current state of the field, including a focus on select studies that highlight the dynamic nature of animal signalling. We then introduce core concepts from systems biology (redundancy, degeneracy, pluripotentiality, and modularity) and discuss their relationships with system properties (e.g. robustness, flexibility, evolvability). We translate systems concepts into an animal communication framework and accentuate their utility through a case study. Finally, we demonstrate how consideration of the system-level organization of animal communication poses new practical research questions that will aid our understanding of how and why animal displays are so complex. © 2016 The Author(s).

  3. OFDM systems for wireless communications

    CERN Document Server

    Narasimhamurthy, Adarsh

    2010-01-01

    Orthogonal Frequency Division Multiplexing (OFDM) systems are widely used in the standards for digital audio/video broadcasting, WiFi and WiMax. Being a frequency-domain approach to communications, OFDM has important advantages in dealing with the frequency-selective nature of high data rate wireless communication channels. As the needs for operating with higher data rates become more pressing, OFDM systems have emerged as an effective physical-layer solution.This short monograph is intended as a tutorial which highlights the deleterious aspects of the wireless channel and presents why OFDM is

  4. Time reversal communication system

    Science.gov (United States)

    Candy, James V.; Meyer, Alan W.

    2008-12-02

    A system of transmitting a signal through a channel medium comprises digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. The channel medium may be air, earth, water, tissue, metal, and/or non-metal.

  5. Atmospheric Optical Communication Systems.

    Science.gov (United States)

    1981-02-01

    Tnteral system noise due to dark current id is Oven by . 1d = 2qGrB"" (2-9) Dark current is due to detecor biasing in some instances, and in somue...8217 without extansive pro- gr-=:ing exer’ence. Although. the znodel is designed to be Lteracdve, slight mod-.- i~cadons winl ezw :&31 r~ing of the progrsm

  6. Combined peak-to-average power ratio reduction and physical layer security enhancement in optical orthogonal frequency division multiplexing visible-light communication systems

    Science.gov (United States)

    Wang, Zhongpeng; Chen, Shoufa

    2016-07-01

    A physical encryption scheme for discrete Hartley transform (DHT) precoded orthogonal frequency division multiplexing (OFDM) visible-light communication (VLC) systems using frequency domain chaos scrambling is proposed. In the scheme, the chaos scrambling, which is generated by a modified logistic mapping, is utilized to enhance the physical layer of security, and the DHT precoding is employed to reduce of OFDM signal for OFDM-based VLC. The influence of chaos scrambling on peak-to-average power ratio (PAPR) and bit error rate (BER) of systems is studied. The experimental simulation results prove the efficiency of the proposed encryption method for DHT-precoded, OFDM-based VLC systems. Furthermore, the influence of the proposed encryption to the PAPR and BER of systems is evaluated. The experimental results show that the proposed security scheme can protect the DHT-precoded, OFDM-based VLC from eavesdroppers, while keeping the good BER performance of DHT-precoded systems. The BER performance of the encrypted and DHT-precoded system is almost the same as that of the conventional DHT-precoded system without encryption.

  7. Chaotic systems in optical communications

    Science.gov (United States)

    Siuzdak, J.

    2016-09-01

    Communications application of chaotic oscillations of lasers with optoelectronic feedback was discussed. The possibility of eavesdropping of the transmission was analyzed. It was proved that if the rogue party precisely knows parameters of the chaotic system it may recreate the entire signals solely by observation of the optical signal power causing security breach.

  8. Global services systems - Space communication

    Science.gov (United States)

    Shepphird, F. H.; Wolbers, H. L.

    1979-01-01

    The requirements projected to the year 2000 for space-based global service systems, including both personal communications and innovative services, are developed based on historic trends and anticipated worldwide demographic and economic growth patterns. The growing demands appear to be best satisfied by developing larger, more sophisticated space systems in order to reduce the size, complexity, and expense of ground terminals. The availability of low-cost ground terminals will, in turn, further stimulate the generation of new services and new customers.

  9. Combining Agile and Traditional: Customer Communication in Distributed Environment

    Science.gov (United States)

    Korkala, Mikko; Pikkarainen, Minna; Conboy, Kieran

    Distributed development is a radically increasing phenomenon in modern software development environments. At the same time, traditional and agile methodologies and combinations of those are being used in the industry. Agile approaches place a large emphasis on customer communication. However, existing knowledge on customer communication in distributed agile development seems to be lacking. In order to shed light on this topic and provide practical guidelines for companies in distributed agile environments, a qualitative case study was conducted in a large globally distributed software company. The key finding was that it might be difficult for an agile organization to get relevant information from a traditional type of customer organization, even though the customer communication was indicated to be active and utilized via multiple different communication media. Several challenges discussed in this paper referred to "information blackout" indicating the importance of an environment fostering meaningful communication. In order to evaluate if this environment can be created a set of guidelines is proposed.

  10. Cultural selection drives the evolution of human communication systems.

    Science.gov (United States)

    Tamariz, Monica; Ellison, T Mark; Barr, Dale J; Fay, Nicolas

    2014-08-07

    Human communication systems evolve culturally, but the evolutionary mechanisms that drive this evolution are not well understood. Against a baseline that communication variants spread in a population following neutral evolutionary dynamics (also known as drift models), we tested the role of two cultural selection models: coordination- and content-biased. We constructed a parametrized mixed probabilistic model of the spread of communicative variants in four 8-person laboratory micro-societies engaged in a simple communication game. We found that selectionist models, working in combination, explain the majority of the empirical data. The best-fitting parameter setting includes an egocentric bias and a content bias, suggesting that participants retained their own previously used communicative variants unless they encountered a superior (content-biased) variant, in which case it was adopted. This novel pattern of results suggests that (i) a theory of the cultural evolution of human communication systems must integrate selectionist models and (ii) human communication systems are functionally adaptive complex systems.

  11. Short-range communication system

    Science.gov (United States)

    Alhorn, Dean C. (Inventor); Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

    2012-01-01

    A short-range communication system includes an antenna, a transmitter, and a receiver. The antenna is an electrical conductor formed as a planar coil with rings thereof being uniformly spaced. The transmitter is spaced apart from the plane of the coil by a gap. An amplitude-modulated and asynchronous signal indicative of a data stream of known peak amplitude is transmitted into the gap. The receiver detects the coil's resonance and decodes same to recover the data stream.

  12. Study on Airspace Covert Communication Algorithm of Covert Communication System

    Directory of Open Access Journals (Sweden)

    Yinpu Zhang

    2012-04-01

    Full Text Available Based on the security of information transmission through network in the information society, the paper puts forward covert communication technology which is more reliable than the prior encryption algorithm, analyzes channel covertness and information hiding of covert communication technology based on spread-spectrum communication technology, and establishes a covert communication system including image steganalysis, Arnold transformation and scrambling of carrier image, embedding of secret information, generation of encrypted image and recovering of carrier image by image-based covert communication technology. The simulation result shows: in order to ensure there is no serious degrading problem after embedding the secret information, the carrier image must have a large capacity; the larger the scrambling times is, the better the scrambling and encrypting effect is. Therefore, the airspace covert communication algorithm based on spread-spectrum communication technology well achieves safe transmission of information and has good application prospect.

  13. Communications Systems for Mobile Robotics

    Energy Technology Data Exchange (ETDEWEB)

    Futterman, J A; Pao, H

    2003-12-08

    Performance Confirmation is the activity by which the Yucca Mountain Project confirms that the engineered and natural containment barriers of this national nuclear waste repository are performing as predicted, so that an eventual decision to close the repository can be made. This activity involves systems that must be inspected and, in some cases, serviced by mobile robots. This paper discusses systems for underground mobile robot communications, including requirements, environments, options, issues, and down-select criteria. We reviewed a variety of systems, including Slotted Waveguide, Powerline Carrier, Leaky Feeder, Photonic Bandgap Fiber, Free-Space Optics, Millimeter Waves, Terahertz Systems, and RF Systems (including IEEE 802.11 a,b, and g, and Ultra-Wideband radio).

  14. An Experimental Study of the Emergence of Human Communication Systems

    Science.gov (United States)

    Galantucci, Bruno

    2005-01-01

    The emergence of human communication systems is typically investigated via 2 approaches with complementary strengths and weaknesses: naturalistic studies and computer simulations. This study was conducted with a method that combines these approaches. Pairs of participants played video games requiring communication. Members of a pair were…

  15. Communication System Architecture for Planetary Exploration

    Science.gov (United States)

    Braham, Stephen P.; Alena, Richard; Gilbaugh, Bruce; Glass, Brian; Norvig, Peter (Technical Monitor)

    2001-01-01

    Future human missions to Mars will require effective communications supporting exploration activities and scientific field data collection. Constraints on cost, size, weight and power consumption for all communications equipment make optimization of these systems very important. These information and communication systems connect people and systems together into coherent teams performing the difficult and hazardous tasks inherent in planetary exploration. The communication network supporting vehicle telemetry data, mission operations, and scientific collaboration must have excellent reliability, and flexibility.

  16. Communications satellite system for Africa

    Science.gov (United States)

    Kriegl, W.; Laufenberg, W.

    1980-09-01

    Earlier established requirement estimations were improved upon by contacting African administrations and organizations. An enormous demand is shown to exist for telephony and teletype services in rural areas. It is shown that educational television broadcasting should be realized in the current African transport and communications decade (1978-1987). Radio broadcasting is proposed in order to overcome illiteracy and to improve educational levels. The technical and commercial feasibility of the system is provided by computer simulations which demonstrate how the required objectives can be fulfilled in conjunction with ground networks.

  17. Wireless Augmented Reality Communication System

    Science.gov (United States)

    Devereaux, Ann (Inventor); Jedrey, Thomas (Inventor); Agan, Martin (Inventor)

    2016-01-01

    The system of the present invention is a highly integrated radio communication system with a multimedia co-processor which allows true two-way multimedia (video, audio, data) access as well as real-time biomedical monitoring in a pager-sized portable access unit. The system is integrated in a network structure including one or more general purpose nodes for providing a wireless-to-wired interface. The network architecture allows video, audio and data (including biomedical data) streams to be connected directly to external users and devices. The portable access units may also be mated to various non-personal devices such as cameras or environmental sensors for providing a method for setting up wireless sensor nets from which reported data may be accessed through the portable access unit. The reported data may alternatively be automatically logged at a remote computer for access and viewing through a portable access unit, including the user's own.

  18. Do Animal Communication Systems Have Phonemes?

    Science.gov (United States)

    Bowling, Daniel L; Fitch, W Tecumseh

    2015-10-01

    Biologists often ask whether animal communication systems make use of conceptual entities from linguistics, such as semantics or syntax. A new study of an Australian bird species argues that their communication system has phonemes, but we argue that imposing linguistic concepts obscures, rather than clarifyies, communicative function. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Modeling of digital communication systems using SIMULINK

    CERN Document Server

    Giordano, Arthur A

    2015-01-01

    Arthur Giordano, PhD, is a consultant in the field of military and commercial communications specializing in wireless communications. He is a co-founder of G5 Scientific, LLC, is a senior member of the IEEE and has taught graduate communications courses. He has developed numerous models using MathWorks®' SIMULINK®® to characterize digital communications systems. Allen Levesque, PhD, is a consultant specializing in digital communications systems, and is a partner in G5 Scientific, LLC. He has taught graduate courses in digital communications at Worcester Polytechnic Institute and is currently

  20. Advances in communication systems and electrical engineering

    CERN Document Server

    Huang, Xu

    2008-01-01

    This volume contains contributions from participants in the 2007 International Multiconference of Engineers and Computer Scientists Topics covered include communications theory, communications protocols, network management, wireless networks, telecommunication, electronics, power engineering, control engineering, signal processing, and industrial applications. The book will offer the states of arts of tremendous advances in communication systems and electrical engineering and also serve as an excellent reference work for researchers and graduate students working with/on communication systems a

  1. GAS MAIN SENSOR AND COMMUNICATIONS NETWORK SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Hagen Schempf, Ph.D.

    2003-02-27

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. A prototype system was built for low-pressure cast-iron mains and tested in a spider- and serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The prototype unit combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-slave architecture to collect data from a distributed spider-arrangement, and in a master-repeater-slave configuration in serial or ladder-network arrangements. It was found that the system was capable of performing all data-sampling and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and valuable data was collected in order to determine how to improve on range and data-quality in the future.

  2. Joint detection and combining schemes in MIMO-HARQ systems

    Institute of Scientific and Technical Information of China (English)

    XIE Gang; XIONG Fang; ZHAO Yi; LIU Yuan-an

    2007-01-01

    This article mainly investigates the combining schemes for hybrid automatic retransmission request (HARQ) protocols in multiple-input multiple-output (MIMO) wireless communication systems. A novel scheme, which joins MIMO detection and HARQ combining, called mid-combining, is presented in this article. Based on the position of HARQ combining, we classify the HARQ combining schemes into three types, named pre-combining, mid-combining, and post-combining. The simulation results show that mid- combining can increase the system throughput for all SNRs.

  3. New Military Strategic Communications System

    Science.gov (United States)

    2007-05-01

    54 O’Day, 6. 55 Perlmutter, David D. The Manship School guide to Political Communication . Louisiana State University Press...Westport: Praeger Publishing, 2006. Perlmutter, David D. The Manship School guide to Political Communication . Louisiana State University Press

  4. Smart Grid Communications System Blueprint

    Science.gov (United States)

    Clark, Adrian; Pavlovski, Chris

    2010-10-01

    Telecommunications operators are well versed in deploying 2G and 3G wireless networks. These networks presently support the mobile business user and/or retail consumer wishing to place conventional voice calls and data connections. The electrical power industry has recently commenced transformation of its distribution networks by deploying smart monitoring and control devices throughout their networks. This evolution of the network into a `smart grid' has also motivated the need to deploy wireless technologies that bridge the communication gap between the smart devices and information technology systems. The requirements of these networks differ from traditional wireless networks that communications operators have deployed, which have thus far forced energy companies to consider deploying their own wireless networks. We present our experience in deploying wireless networks to support the smart grid and highlight the key properties of these networks. These characteristics include application awareness, support for large numbers of simultaneous cell connections, high service coverage and prioritized routing of data. We also outline our target blueprint architecture that may be useful to the industry in building wireless and fixed networks to support the smart grid. By observing our experiences, telecommunications operators and equipment manufacturers will be able to augment their current networks and products in a way that accommodates the needs of the emerging industry of smart grids and intelligent electrical networks.

  5. A randomized model for communicating embedded systems

    NARCIS (Netherlands)

    Bujorianu, M.C.; Bujorianu, L.M.

    2008-01-01

    Nowadays, there is an intense research activity in designing systems that operate in real life, physical environments. This research is spanned by various areas in computer science and engineering: embedded systems, reactive systems, wireless communications, hybrid systems, stochastic processes, etc

  6. Expert Systems as Tools for Technical Communicators.

    Science.gov (United States)

    Grider, Daryl A.

    1994-01-01

    Discusses expertise, what an expert system is, what an expert system shell is, what expert systems can and cannot do, knowledge engineering and technical communicators, and planning and managing expert system projects. (SR)

  7. A randomized model for communicating embedded systems

    NARCIS (Netherlands)

    Bujorianu, M.C.; Bujorianu, L.M.

    2008-01-01

    Nowadays, there is an intense research activity in designing systems that operate in real life, physical environments. This research is spanned by various areas in computer science and engineering: embedded systems, reactive systems, wireless communications, hybrid systems, stochastic processes,

  8. Wireless Augmented Reality Communication System

    Science.gov (United States)

    Devereaux, Ann (Inventor); Jedrey, Thomas (Inventor); Agan, Martin (Inventor)

    2017-01-01

    A portable unit is for video communication to select a user name in a user name network. A transceiver wirelessly accesses a communication network through a wireless connection to a general purpose node coupled to the communication network. A user interface can receive user input to log on to a user name network through the communication network. The user name network has a plurality of user names, at least one of the plurality of user names is associated with a remote portable unit, logged on to the user name network and available for video communication.

  9. Transition From NASA Space Communication Systems to Commerical Communication Products

    Science.gov (United States)

    Ghazvinian, Farzad; Lindsey, William C.

    1994-01-01

    Transitioning from twenty-five years of space communication system architecting, engineering and development to creating and marketing of commercial communication system hardware and software products is no simple task for small, high-tech system engineering companies whose major source of revenue has been the U.S. Government. Yet, many small businesses are faced with this onerous and perplexing task. The purpose of this talk/paper is to present one small business (LinCom) approach to taking advantage of the systems engineering expertise and knowledge captured in physical neural networks and simulation software by supporting numerous National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) projects, e.g., Space Shuttle, TDRSS, Space Station, DCSC, Milstar, etc. The innovative ingredients needed for a systems house to transition to a wireless communication system products house that supports personal communication services and networks (PCS and PCN) development in a global economy will be discussed. Efficient methods for using past government sponsored space system research and development to transition to VLSI communication chip set products will be presented along with notions of how synergy between government and industry can be maintained to benefit both parties.

  10. Neuronal communication through coherence in the human motor system

    NARCIS (Netherlands)

    Schoffelen, J.M.

    2007-01-01

    This thesis explores the concept of neuronal communication through oscillatory synchronization. For most of the described research, we used the human motor system as a model system, in particular the cortico spinal system, in combination with non invasive recording techniques. Oscillatory

  11. 5G multimedia massive MIMO communications systems

    OpenAIRE

    Ge, Xiaohu; Wang, Haichao; Zi, Ran; Li, Qiang; Ni, Qiang

    2016-01-01

    In the fifth generation (5G) wireless communication systems, a majority of the traffic demands are contributed by various multimedia applications. To support the future 5G multimedia communication systems, the massive multiple-input multiple-output (MIMO) technique is recognized as a key enabler because of its high spectral efficiency. The massive antennas and radio frequency chains not only improve the implementation cost of 5G wireless communication systems but also result in an intense mut...

  12. GAS MAIN SENSOR AND COMMUNICATIONS NETWORK SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Hagen Schempf

    2004-09-30

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. In Phase II of this three-phase program, an improved prototype system was built for low-pressure cast-iron and high-pressure steel (including a no-blow installation system) mains and tested in a serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The experiment was carried out in several open-hole excavations over a multi-day period. The prototype units (3 total) combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-repeater-slave configuration in serial or ladder-network arrangements. It was verified that the system was capable of performing all data-sampling, data-storage and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and the system was demonstrated to run off in-ground battery- and above-ground solar power. The remote datalogger access and storage-card features were demonstrated and used to log and post-process system data. Real-time data-display on an updated Phase-I GUI was used for in-field demonstration and troubleshooting.

  13. Communication Systems and Study Method for Active Distribution Power systems

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    Due to the involvement and evolvement of communication technologies in contemporary power systems, the applications of modern communication technologies in distribution power system are becoming increasingly important. In this paper, the International Organization for Standardization (ISO....... The suitability of the communication technology to the distribution power system with active renewable energy based generation units is discussed. Subsequently the typical possible communication systems are studied by simulation. In this paper, a novel method of integrating communication system impact into power...... system simulation is presented to address the problem of lack of off-shelf research tools on the power system communication. The communication system is configured and studied by the OPNET, and the performance of an active distribution power system integrated with the communication system is simulated...

  14. 33 CFR 127.111 - Communications systems.

    Science.gov (United States)

    2010-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.111 Communications systems. (a) The...

  15. Communications and Intelligent Systems Division Overview

    Science.gov (United States)

    Emerson, Dawn

    2017-01-01

    Provides expertise, and plans, conducts and directs research and engineering development in the competency fields of advanced communications and intelligent systems technologies for applications in current and future aeronautics and space systems.Advances communication systems engineering, development and analysis needed for Glenn Research Center's leadership in communications and intelligent systems technology. Focus areas include advanced high frequency devices, components, and antennas; optical communications, health monitoring and instrumentation; digital signal processing for communications and navigation, and cognitive radios; network architectures, protocols, standards and network-based applications; intelligent controls, dynamics and diagnostics; and smart micro- and nano-sensors and harsh environment electronics. Research and discipline engineering allow for the creation of innovative concepts and designs for aerospace communication systems with reduced size and weight, increased functionality and intelligence. Performs proof-of-concept studies and analyses to assess the impact of the new technologies.

  16. Acoustic Communications Measurement Systems (ACOMMS)

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Design and develop adaptive signal processing techniques to improve underwater acoustic communications and networking. Phase coherent and incoherent signal...

  17. How do communication systems emerge?

    Science.gov (United States)

    Scott-Phillips, Thomas C; Blythe, Richard A; Gardner, Andy; West, Stuart A

    2012-05-22

    Communication involves a pair of behaviours--a signal and a response--that are functionally interdependent. Consequently, the emergence of communication involves a chicken-and-egg problem: if signals and responses are dependent on one another, then how does such a relationship emerge in the first place? The empirical literature suggests two solutions to this problem: ritualization and sensory manipulation; and instances of ritualization appear to be more common. However, it is not clear from a theoretical perspective why this should be the case, nor if there are any other routes to communication. Here, we develop an analytical model to examine how communication can emerge. We show that: (i) a state of non-interaction is evolutionarily stable, and so communication will not necessarily emerge even when it is in both parties' interest; (ii) the conditions for sensory manipulation are more stringent than for ritualization, and hence ritualization is likely to be more common; and (iii) communication can arise by a third route, when the intention to communicate can itself be communicated, but this may be limited to humans. More generally, our results demonstrate the utility of a functional approach to communication.

  18. Combined radar and telemetry system

    Energy Technology Data Exchange (ETDEWEB)

    Rodenbeck, Christopher T.; Young, Derek; Chou, Tina; Hsieh, Lung-Hwa; Conover, Kurt; Heintzleman, Richard

    2017-08-01

    A combined radar and telemetry system is described. The combined radar and telemetry system includes a processing unit that executes instructions, where the instructions define a radar waveform and a telemetry waveform. The processor outputs a digital baseband signal based upon the instructions, where the digital baseband signal is based upon the radar waveform and the telemetry waveform. A radar and telemetry circuit transmits, simultaneously, a radar signal and telemetry signal based upon the digital baseband signal.

  19. Computational Interpersonal Communication: Communication Studies and Spoken Dialogue Systems

    Directory of Open Access Journals (Sweden)

    David J. Gunkel

    2016-09-01

    Full Text Available With the advent of spoken dialogue systems (SDS, communication can no longer be considered a human-to-human transaction. It now involves machines. These mechanisms are not just a medium through which human messages pass, but now occupy the position of the other in social interactions. But the development of robust and efficient conversational agents is not just an engineering challenge. It also depends on research in human conversational behavior. It is the thesis of this paper that communication studies is best situated to respond to this need. The paper argues: 1 that research in communication can supply the information necessary to respond to and resolve many of the open problems in SDS engineering, and 2 that the development of SDS applications can provide the discipline of communication with unique opportunities to test extant theory and verify experimental results. We call this new area of interdisciplinary collaboration “computational interpersonal communication” (CIC

  20. FEC combined burst-modem for business satellite communications use

    Science.gov (United States)

    Murakami, K.; Miyake, M.; Fuji, T.; Moritani, Y.; Fujino, T.

    The authors recently developed two types of FEC (forward error correction) combined modems both applicable to low-data-rate and intermediate-data-rate TDMA international satellite communications. Each FEC combined modem consists of a QPSK (quadrature phase-shift keyed) modem, a convolutional encoder, and a Viterbi decoder. Both modems are designed taking into consideration the fast acquisition of the carrier and bit timing and the low cycle slipping rate in the low-carrier-to-noise-ratio environment. Attention is paid to designing the Viterbi decoder to be operated in a situation in which successive bursts may have different coding rates according to the punctured coding scheme. The overall scheme of the FEC combined modems are presented, and some of the key technologies applied in developing them are outlined. The hardware implementation and experimentation are also discussed. The measured data are compared with results of theoretical analysis, and relatively good performances are obtained.

  1. Why language really is not a communication system

    Directory of Open Access Journals (Sweden)

    Anne Colette Reboul

    2015-09-01

    Full Text Available While most evolutionary scenarios for language see it as a communication system with consequences on the language-ready brain, there are major difficulties for such a view. First, language has a core combination of features—semanticity, discrete infinity, decoupling—that makes it unique among communication systems and that raise deep problems for the view that it evolved for communication. Second, extant models of communication systems—the code model of communication (see Millikan 2005 and the ostensive model of communication (see Scott-Phillips 2015 cannot account for language evolution. I propose an alternative view, according to which language first evolved as a cognitive tool, following Fodor’s (1975, 2008 Language of Thought Hypothesis, and was then expiated (externalized for communication. On this view, a language-ready brain is a brain profoundly reorganized in terms of connectivity, allowing the human conceptual system to emerge, triggering the emergence of syntax. Language as used in communication inherited its core combination of features from the Language of Thought.

  2. SAW based systems for mobile communications satellites

    Science.gov (United States)

    Peach, R. C.; Miller, N.; Lee, M.

    1993-01-01

    Modern mobile communications satellites, such as INMARSAT 3, EMS, and ARTEMIS, use advanced onboard processing to make efficient use of the available L-band spectrum. In all of these cases, high performance surface acoustic wave (SAW) devices are used. SAW filters can provide high selectivity (100-200 kHz transition widths), combined with flat amplitude and linear phase characteristics; their simple construction and radiation hardness also makes them especially suitable for space applications. An overview of the architectures used in the above systems, describing the technologies employed, and the use of bandwidth switchable SAW filtering (BSSF) is given. The tradeoffs to be considered when specifying a SAW based system are analyzed, using both theoretical and experimental data. Empirical rules for estimating SAW filter performance are given. Achievable performance is illustrated using data from the INMARSAT 3 engineering model (EM) processors.

  3. Combined spatial diversity and time equalization for broadband multiple channel underwater acoustic communications

    Science.gov (United States)

    Skoro Kaskarovska, Violeta

    High data rate acoustic communications become feasible with the use of communication systems that operate at high frequency. The high frequency acoustic transmission in shallow water endures severe distortion as a result of the extensive intersymbol interference and Doppler shift, caused by the time variable multipath nature of the channel. In this research a Single Input Multiple Output (SIMO) acoustic communication system is developed to improve the reliability of the high data rate communications at short range in the shallow water acoustic channel. The proposed SIMO communication system operates at very high frequency and combines spatial diversity and decision feedback equalizer in a multilevel adaptive configuration. The first configuration performs selective combining on the equalized signals from multiple receivers and generates quality feedback parameter for the next level of combining. The second configuration implements a form of turbo equalization to evaluate the individual receivers using the feedback parameters as decision symbols. The improved signals from individual receivers are used in the next iteration of selective combining. Multiple iterations are used to achieve optimal estimate of the received signal. The multilevel adaptive configuration is evaluated on experimental and simulated data using SIMO system with three, four and five receivers. The simulation channel model developed for this research is based on experimental channel and Rician fading channel model. The performance of the channel is evaluated in terms of Bit Error Rate (BER) and Signal-to-Noise-and-Interference Ratio (SNIR). Using experimental data with non-zero BER, multilevel adaptive spatial diversity can achieve BER of 0 % and SNIR gain of 3 dB. The simulation results show that the average BER and SNIR after multilevel combining improve dramatically compared to the single receiver, even in case of extremely high BER of individual received signals. The results demonstrate the

  4. Novel Reduced-Feedback Wireless Communication Systems

    KAUST Repository

    Shaqfeh, Mohammad Obaidah

    2011-11-20

    Modern communication systems apply channel-aware adaptive transmission techniques and dynamic resource allocation in order to exploit the peak conditions of the fading wireless links and to enable significant performance gains. However, conveying the channel state information among the users’ mobile terminals into the access points of the network consumes a significant portion of the scarce air-link resources and depletes the battery resources of the mobile terminals rapidly. Despite its evident drawbacks, the channel information feedback cannot be eliminated in modern wireless networks because blind communication technologies cannot support the ever-increasing transmission rates and high quality of experience demands of current ubiquitous services. Developing new transmission technologies with reduced-feedback requirements is sought. Network operators will benefit from releasing the bandwidth resources reserved for the feedback communications and the clients will enjoy the extended battery life of their mobile devices. The main technical challenge is to preserve the prospected transmission rates over the network despite decreasing the channel information feedback significantly. This is a noteworthy research theme especially that there is no mature theory for feedback communication in the existing literature despite the growing number of publications about the topic in the last few years. More research efforts are needed to characterize the trade-off between the achievable rate and the required channel information and to design new reduced-feedback schemes that can be flexibly controlled based on the operator preferences. Such schemes can be then introduced into the standardization bodies for consideration in next generation broadband systems. We have recently contributed to this field and published several journal and conference papers. We are the pioneers to propose a novel reduced-feedback opportunistic scheduling scheme that combines many desired features

  5. Phase-Modulated Optical Communication Systems

    CERN Document Server

    Ho, Keang-Po

    2005-01-01

    Fiber-optic communication systems have revolutionized our telecommunication infrastructures – currently, almost all telephone land-line, cellular, and internet communications must travel via some form of optical fibers. In these transmission systems, neither the phase nor frequency of the optical signal carries information – only the intensity of the signal is used. To transmit more information in a single optical carrier, the phase of the optical carrier must be explored. As a result, there is renewed interest in phase-modulated optical communications, mainly in direct-detection DPSK signals for long-haul optical communication systems. When optical amplifiers are used to maintain certain signal level among the fiber link, the system is limited by amplifier noises and fiber nonlinearities. Phase-Modulated Optical Communication Systems surveys this newly popular area, covering the following topics: The transmitter and receiver for phase-modulated coherent lightwave systems Method for performance analysis o...

  6. Systems and Methods for Radar Data Communication

    Science.gov (United States)

    Bunch, Brian (Inventor); Szeto, Roland (Inventor); Miller, Brad (Inventor)

    2013-01-01

    A radar information processing system is operable to process high bandwidth radar information received from a radar system into low bandwidth radar information that may be communicated to a low bandwidth connection coupled to an electronic flight bag (EFB). An exemplary embodiment receives radar information from a radar system, the radar information communicated from the radar system at a first bandwidth; processes the received radar information into processed radar information, the processed radar information configured for communication over a connection operable at a second bandwidth, the second bandwidth lower than the first bandwidth; and communicates the radar information from a radar system, the radar information communicated from the radar system at a first bandwidth.

  7. Technical comparison of several global mobile satellite communications systems

    Science.gov (United States)

    Comparetto, Gary M.

    The era of satellite-based mobile satellite communications (MSC) systems started with the first MARISAT satellite which was launched into a geostationary orbit over the Pacific Ocean in 1976 to provide communications between ships and shore stations. The combination of high cost and unacceptably large equipment has kept the space-based MSC systems from appealing to the wider market of personal mobile communications. The progress made over the last ten years, however, in digital voice processing, satellite technology, and component miniaturization has resulted in the viability of satellite-based mobile satellite communications systems to meet the growing market in personal mobile communications using handsets similar to those currently in use with land-based cellular systems. Three of the more mature LEO/MEO satellite systems are addressed in this paper including GLOBALSTAR, Iridium, and Odyssey. The system architectures of each system are presented along with a description of the satellite and user handset designs and the multiaccess techniques employed. It will be shown that, although a number of similarities exist among the system addressed, each system is unique in a variety of significant design areas. It is concluded that the technical feasibility of satellite-based mobile satellite communications systems seems to be secure. It will be challenging, however, for the vendors to actually develop and deploy these systems in a cost effective, timely, and reliable way that meets a continually evolving set of requirements based upon a rapidly changing technology base.

  8. Synchronization Techniques for Chaotic Communication Systems

    CERN Document Server

    Jovic, Branislav

    2011-01-01

    Since the early 1990s, when synchronization of chaotic communication systems became a popular research subject, a vast number of scientific papers have been published. However, most of today's books on chaotic communication systems deal exclusively with the systems where perfect synchronization is assumed, an assumption which separates theoretical from practical, real world, systems. This book is the first of its kind dealing exclusively with the synchronization techniques for chaotic communication systems. It describes a number of novel robust synchronization techniques, which there is a lack

  9. COMMUNICATION AND INFORMATION SYSTEM MANAGEMENT INTERNATIONAL

    Directory of Open Access Journals (Sweden)

    Mircea Alexandru Răduţeanu

    2012-01-01

    Full Text Available In recent decades international management itself as a separate component of the general science of leadership, is an intercultural management. In this context of globalization, computerization, any business that wants have a modern management should have a structured information system based on communication, overall objective consisting in providing accurate data in real time all parties, increasing the level of communication. Given these considerations, we conducted this work trying to highlight the role of communication in achieving a modern, emphasizing international management features.The paper is divided into 6 parts, prefaced by an introduction of the paper we presented and completed within a set of conclusions on the effectiveness of communication. During the other paragraphs, we present the theoretical concepts of international management, communication, after which I stressed the role of information communication, managerial communication and will then focus on the process, taking stock of its specific stages in international management.

  10. Autonomous grain combine control system

    Science.gov (United States)

    Hoskinson, Reed L.; Kenney, Kevin L.; Lucas, James R.; Prickel, Marvin A.

    2013-06-25

    A system for controlling a grain combine having a rotor/cylinder, a sieve, a fan, a concave, a feeder, a header, an engine, and a control system. The feeder of the grain combine is engaged and the header is lowered. A separator loss target, engine load target, and a sieve loss target are selected. Grain is harvested with the lowered header passing the grain through the engaged feeder. Separator loss, sieve loss, engine load and ground speed of the grain combine are continuously monitored during the harvesting. If the monitored separator loss exceeds the selected separator loss target, the speed of the rotor/cylinder, the concave setting, the engine load target, or a combination thereof is adjusted. If the monitored sieve loss exceeds the selected sieve loss target, the speed of the fan, the size of the sieve openings, or the engine load target is adjusted.

  11. Communication for command and control systems

    CERN Document Server

    Morris, D J

    1983-01-01

    Communication for Command and Control Systems provides a thorough exposition of the basic theoretical and practical features involved in the design of communication networks for command and control systems. This book focuses primarily on the practical side of computer-controlled communication. This text concentrates on the communication sides of the subject by surveying the means of transferring data between the various processing points and by appraising their potential advantages and possible defects in implementation. In this respect, this book should prove useful for the practicing enginee

  12. Reconfigurable/Reprogrammable Communications Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's latest effort in developing a common platform for space communication and navigation systems is the Space Telecommunications Radio System (STRS) standard. It...

  13. Economics of satellite communications systems

    Science.gov (United States)

    Pritchard, Wilbur L.

    This paper is partly a tutorial, telling systematically how one goes about calculating the total annual costs of a satellite communications system, and partly the expression of some original ideas on the choice of parameters so as to minimize these costs. The calculation of costs can be divided into two broad categories. The first is technical and is concerned with estimating what particular equipment will cost and what will be the annual expense to maintain and operate it. One starts in the estimation of any new system by listing the principal items of equipment, such as satellites, earth stations of various sizes and functions, telemetry and tracking equipment and terrestrial interfaces, and then estimating how much each item will cost. Methods are presented for generating such estimates, based on a knowledge of the gross parameters, such as antenna size, coverage area, transmitter power and information rate. These parameters determine the system performance and it is usually possible, knowing them, to estimate the costs of the equipment rather well. Some formulae based on regression analyses are presented. Methods are then given for estimating closely related expenses, such as maintenance and operation, and then an approximate method is developed for estimating terrestrial interconnection costs. It is pointed out that in specific cases when tariff and geographical information are available, it is usually better to work with specific data, but nonetheless it is often desirable, especially in global system estimating, to approximate these interconnect costs without recourse to individual tariffs. The procedure results in a set of costs for the purchase of equipment and its maintenance, and a schedule of payments. Some payments will be incurred during the manufacture of the satellite and before any systems operation, but many will not be incurred until the system is no longer in use, e.g. incentives. In any case, with the methods presented in the first section, one

  14. Ripples in Communication: Reconfigurable and Adaptive Wireless Communication Systems based on Wavelet Packet Modulators

    NARCIS (Netherlands)

    Lakshmanan, M.K.

    2011-01-01

    Wavelet Packet Modulation (WPM) is a multi-carrier transmission technique that uses orthogonal wavelet packet bases to combine a collection of information bits into a single composite signal. This system can be considered as a viable alternative, for wide-band communication, to the popular

  15. Ripples in Communication: Reconfigurable and Adaptive Wireless Communication Systems based on Wavelet Packet Modulators

    NARCIS (Netherlands)

    Lakshmanan, M.K.

    2011-01-01

    Wavelet Packet Modulation (WPM) is a multi-carrier transmission technique that uses orthogonal wavelet packet bases to combine a collection of information bits into a single composite signal. This system can be considered as a viable alternative, for wide-band communication, to the popular Orthogona

  16. Experimental millimeter-wave satellite communications system

    Science.gov (United States)

    Suzuki, Yoshiaki; Shimada, Masaaki; Arimoto, Yoshinori; Shiomi, Tadashi; Kitazume, Susumu

    This paper describes an experimental system of millimeter-wave satellite communications via Japan's Engineering Test Satellite-VI (ETS-VI) and a plan of experiments. Two experimental missions are planned using ETS-VI millimeter-wave (43/38 GHz bands) transponder, considering the millimeter-wave characteristics such as large transmission capacity and possibility to construct a small earth station with a high gain antenna. They are a personal communication system and an inter-satellite communication system. Experimental system including the configuration and the fundamental functions of the onboard transponder and the outline of the experiments are presented.

  17. Airbreathing combined cycle engine systems

    Science.gov (United States)

    Rohde, John

    1992-01-01

    The Air Force and NASA share a common interest in developing advanced propulsion systems for commercial and military aerospace vehicles which require efficient acceleration and cruise operation in the Mach 4 to 6 flight regime. The principle engine of interest is the turboramjet; however, other combined cycles such as the turboscramjet, air turborocket, supercharged ejector ramjet, ejector ramjet, and air liquefaction based propulsion are also of interest. Over the past months careful planning and program implementation have resulted in a number of development efforts that will lead to a broad technology base for those combined cycle propulsion systems. Individual development programs are underway in thermal management, controls materials, endothermic hydrocarbon fuels, air intake systems, nozzle exhaust systems, gas turbines and ramjet ramburners.

  18. How to Bootstrap a Human Communication System

    Science.gov (United States)

    Fay, Nicolas; Arbib, Michael; Garrod, Simon

    2013-01-01

    How might a human communication system be bootstrapped in the absence of conventional language? We argue that motivated signs play an important role (i.e., signs that are linked to meaning by structural resemblance or by natural association). An experimental study is then reported in which participants try to communicate a range of pre-specified…

  19. In Search of a System For Communication.

    Science.gov (United States)

    Remirez, Richard J. F.

    A research project sponsored by Wofford College was launched in the summer of 1974 in Spartanburg, South Carolina, to develop a system of communication by which hospital personnel working in an emergency room could communicate with patients who speak a language other than English. The project followed a year-long research effort of previous work…

  20. Nonoral Communication System Project: 1964-1973.

    Science.gov (United States)

    Vicker, Beverly A., Ed.

    Five papers comprising the monograph describe a nonoral communication program which evolved from the clinical experiences of speech pathologists and physical therapists with severely dysarthric, physically handicapped children in a hospital school. Explicated are such aspects of nonoral communication as oral speech dysfunction systems of nonoral…

  1. Simulating Rain Fade In A Communication System

    Science.gov (United States)

    Shalkhauser, Kurt A.; Nagy, Lawrence A.; Svoboda, James K.

    1994-01-01

    Automated, computer-controlled assembly of electronic equipment developed for use in simulation testing of downlink portion of Earth/satellite microwave digital communication system. Designed to show effects upon performance of system of rain-induced fading in received signal and increases in transmitted power meant to compensate for rain-induced fading. Design of communication system improved iteratively in response to results of simulations, leading eventually to design ensuring clear, uninterrupted transmission of digital signals.

  2. Transceiver and system design for digital communications

    CERN Document Server

    Bullock, Scott R

    2014-01-01

    This is the fourth edition of this successful professional reference book on transceiver design, the device that both sends and receives signals, and its place within the wireless communication system. It gives engineers and others a good intuitive understanding of wireless systems and spread spectrum. New topics covered include cognitive radio, systems, networks, and commercial communications. In addition, many items have been extensively updated to improve the flow of the book and enhance comprehension.

  3. Analog and digital communication systems

    CERN Document Server

    Roden, Martin S

    1996-01-01

    New edition of an introductory text that balances theoretical foundations with practical design. Reorganization and updates in this edition include the section on digital communications as well as design applications and computer exercises: many graphs are prepared and formulas solved using MATLAB...

  4. Communication architectures for systems-on-chip

    CERN Document Server

    Ayala, Jose L

    2011-01-01

    A presentation of state-of-the-art approaches from an industrial applications perspective, Communication Architectures for Systems-on-Chip shows professionals, researchers, and students how to attack the problem of data communication in the manufacture of SoC architectures. With its lucid illustration of current trends and research improving the performance, quality, and reliability of transactions, this is an essential reference for anyone dealing with communication mechanisms for embedded systems, systems-on-chip, and multiprocessor architectures--or trying to overcome existing limitations.

  5. Sensing Traffic Density Combining V2V and V2I Wireless Communications.

    Science.gov (United States)

    Sanguesa, Julio A; Barrachina, Javier; Fogue, Manuel; Garrido, Piedad; Martinez, Francisco J; Cano, Juan-Carlos; Calafate, Carlos T; Manzoni, Pietro

    2015-12-16

    Wireless technologies are making the development of new applications and services in vehicular environments possible since they enable mobile communication between vehicles (V2V), as well as communication between vehicles and infrastructure nodes (V2I). Usually, V2V communications are dedicated to the transmission of small messages mainly focused on improving traffic safety. Instead, V2I communications allow users to access the Internet and benefit from higher level applications. The combination of both V2V and V2I, known as V2X communications, can increase the benefits even further, thereby making intelligent transportation systems (ITS) a reality. In this paper, we introduce V2X-d, a novel architecture specially designed to estimate traffic density on the road. In particular, V2X-d exploits the combination of V2V and V2I communications. Our approach is based on the information gathered by sensors (i.e., vehicles and road side units (RSUs)) and the characteristics of the roadmap topology to accurately make an estimation of the instant vehicle density. The combination of both mechanisms improves the accuracy and coverage area of the data gathered, while increasing the robustness and fault tolerance of the overall approach, e.g., using the information offered by V2V communications to provide additional density information in areas where RSUs are scarce or malfunctioning. By using our collaborative sensing scheme, future ITS solutions will be able to establish adequate dissemination protocols or to apply more efficient traffic congestion reduction policies, since they will be aware of the instantaneous density of vehicles.

  6. Broadcast Communication by System Frequency Modulation

    DEFF Research Database (Denmark)

    Douglass, Philip James; You, Shi; Heussen, Kai

    2012-01-01

    off-nominal system frequency values is a novel narrowband broadcast communications channel between system operators and frequency sensitive distributed energy resources (FS-DER). The feasibility of the proposed system is evaluated on an existing island power system in Denmark. This study shows...

  7. Communication system at Dakshin Gangotri, Antarctica

    Digital Repository Service at National Institute of Oceanography (India)

    Sudhakar, T.

    A reliable communication system is a major requirement for a remote station like 'Dakshin Gangotri' where traditional equipments cannot function effectively due to long distances and peculiar weather and ionospheric conditions. The satellite...

  8. Extreme Environment High Temperature Communication Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of this project is to develop and demonstrate a communications system capable of operation at extreme temperatures and pressures in hostile and corrosive...

  9. Protection of Communication System From Solar Flares

    OpenAIRE

    Karthik, K.(Department of Physics, New York University, New York, NY, United States of America); Shirvram, B.

    2008-01-01

    Solar flares are enormous explosions on the surface of the sun and they release energy of the order of billion megatons of TNThis energy is in the form of electromagnetic radiations such as alpha, gamma, and ultraviolet rays. When exposed to high doses of radiation like 2-15 kilorad (Si), silicon integrated circuits in satellite communication systems fail to operate properly, thus affecting the performance of communication systems. Therefore, the major issue that needs to be addressed is the ...

  10. Spatial Modulation for MIMO Communication Systems

    Directory of Open Access Journals (Sweden)

    Reginaldo Nunes

    2012-11-01

    Full Text Available This work provides a review on the main spatial modulation (SM schemes, suitable to wireless communication systems. Performance, complexity and diversity gain of the three new spatial SM schemes suitable for multiple-input-multiple-output (MIMO communication systems are analyzed: a transmission scheme for spatial modulation (SM scheme; b space shift keying (SSK scheme; c generalized space shift keying (GSSK scheme. These three schemes offer low complexity, higher data rate when compared to single-input-single-output (SISO communication systems, as well as design flexibility, while exploits randomness characteristics of wireless communication channel for data transmission. The paper aims to explore the main features of those three SM schemes and to evaluate the inherent performance-complexity trade-off in order to determine which of those schemes results in a higher energy and spectral efficiencies.

  11. Converging Information and Communication Systems

    DEFF Research Database (Denmark)

    Øst, Alexander

    2003-01-01

    This Ph.D.-project investigates the process of convergence between television and computers. Identifying three “promises of convergence”: interoperability, quality and interactivity, the project examines the key properties of the computer and television sectors, which have had - or are expected...... in the future to have - significant importance to the process and consequences of the convergence. The project focuses on the appliances, i.e. the TV sets, the computers and their peripheral equipment. It also takes into account the infrastructure and signals, which contain and deliver the information...... and communication, as well as the nature of the content and the usage scenarios of consumers....

  12. Simulation of Wireless Digital Communication Systems

    Directory of Open Access Journals (Sweden)

    A. Mohammed

    2004-12-01

    Full Text Available Due to the explosive demands for high speed wireless services, suchas wireless Internet, email and cellular video conferencing, digitalwireless communications has become one of the most exciting researchtopics in electrical and electronic engineering field. The never-endingdemand for such personal and multimedia services, however, demandstechnologies operating at higher data rates and broader bandwidths. Inaddition, the complexity of wireless communication and signalprocessing systems has grown considerably during the past decade.Therefore, powerful computer­aided techniques are required for theprocess of modeling, designing, analyzing and evaluating theperformance of digital wireless communication systems. In this paper wediscuss the basic propagation mechanisms affecting the performance ofwireless communication systems, and present a simple, powerful andefficient way to simulate digital wireless communication systems usingMatlab. The simulated results are compared with the theoreticalanalysis to validate the simulator. The simulator is useful inevaluating the performance of wireless multimedia services and theassociated signal processing structures and algorithms for current andnext generation wireless mobile communication systems.

  13. A Rapid Prototyping Environment for Wireless Communication Embedded Systems

    Science.gov (United States)

    Jones, Bryan A.; Cavallaro, Joseph R.

    2003-12-01

    This paper introduces a rapid prototyping methodology which overcomes important barriers in the design and implementation of digital signal processing (DSP) algorithms and systems on embedded hardware platforms, such as cellular phones. This paper describes rapid prototyping in terms of a simulation/prototype bridge and in terms of appropriate language design. The simulation/prototype bridge combines the strengths of simulation and of prototyping, allowing the designer to develop and evaluate next-generation communications systems, partly in simulation on a host computer and partly as a prototype on embedded hardware. Appropriate language design allows designers to express a communications system as a block diagram, in which each block represents an algorithm specified by a set of equations. Software tools developed for this paper implement both concepts, and have been successfully used in the development of a next-generation code division multiple access (CDMA) cellular wireless communications system.

  14. A Rapid Prototyping Environment for Wireless Communication Embedded Systems

    Directory of Open Access Journals (Sweden)

    Bryan A. Jones

    2003-05-01

    Full Text Available This paper introduces a rapid prototyping methodology which overcomes important barriers in the design and implementation of digital signal processing (DSP algorithms and systems on embedded hardware platforms, such as cellular phones. This paper describes rapid prototyping in terms of a simulation/prototype bridge and in terms of appropriate language design. The simulation/prototype bridge combines the strengths of simulation and of prototyping, allowing the designer to develop and evaluate next-generation communications systems, partly in simulation on a host computer and partly as a prototype on embedded hardware. Appropriate language design allows designers to express a communications system as a block diagram, in which each block represents an algorithm specified by a set of equations. Software tools developed for this paper implement both concepts, and have been successfully used in the development of a next-generation code division multiple access (CDMA cellular wireless communications system.

  15. Physical layer approaches for securing wireless communication systems

    CERN Document Server

    Wen, Hong

    2013-01-01

    This book surveys the outstanding work of physical-layer (PHY) security, including  the recent achievements of confidentiality and authentication for wireless communication systems by channel identification. A practical approach to building unconditional confidentiality for Wireless Communication security by feedback and error correcting code is introduced and a framework of PHY security based on space time block code (STBC) MIMO system is demonstrated.  Also discussed is a scheme which combines cryptographic techniques implemented in the higher layer with the physical layer security approach

  16. Communication and control for networked complex systems

    CERN Document Server

    Peng, Chen; Han, Qing-Long

    2015-01-01

    This book reports on the latest advances in the study of Networked Control Systems (NCSs). It highlights novel research concepts on NCSs; the analysis and synthesis of NCSs with special attention to their networked character; self- and event-triggered communication schemes for conserving limited network resources; and communication and control co-design for improving the efficiency of NCSs. The book will be of interest to university researchers, control and network engineers, and graduate students in the control engineering, communication and network sciences interested in learning the core principles, methods, algorithms and applications of NCSs.

  17. A native IP satellite communications system

    Science.gov (United States)

    Koudelka, O.; Schmidt, M.; Ebert, J.; Schlemmer, H.; Kastner-Puschl, S.; Riedler, W.

    2004-08-01

    ≪ In the framework of ESA's ARTES-5 program the Institute of Applied Systems Technology (Joanneum Research) in cooperation with the Department of Communications and Wave Propagation has developed a novel meshed satellite communications system which is optimised for Internet traffic and applications (L*IP—Local Network Interconnection via Satellite Systems Using the IP Protocol Suite). Both symmetrical and asymmetrical connections are supported. Bandwidth on demand and guaranteed quality of service are key features of the system. A novel multi-frequency TDMA access scheme utilises efficient methods of IP encapsulation. In contrast to other solutions it avoids legacy transport network techniques. While the DVB-RCS standard is based on ATM or MPEG transport cells, the solution of the L*IP system uses variable-length cells which reduces the overhead significantly. A flexible and programmable platform based on Linux machines was chosen to allow the easy implementation and adaptation to different standards. This offers the possibility to apply the system not only to satellite communications, but provides seamless integration with terrestrial fixed broadcast wireless access systems. The platform is also an ideal test-bed for a variety of interactive broadband communications systems. The paper describes the system architecture and the key features of the system.

  18. 5G Wireless Communication Systems

    Directory of Open Access Journals (Sweden)

    Saddam Hossain

    2013-10-01

    Full Text Available As a subscriber becomes more aware of the mobile phone technology, he/she will seek for anappropriate package all together, including all the advanced features of a cellular phone can have. Hence, the search for new technology is always the main intention of the prime cell phone giants to out innovate their competitors. In addition, the main purpose of the fifth generation wireless networks (5G Wireless networks is planned to design the best wireless world that is free from limitations and hindrance of the previous generations.5G technologies will change the way most high bandwidth users access their Mobile Radio Communication (MRC. So, this paper represents, great evolution of 1G (First Generation to 4G yield 5G, introduction to 5G technologies, why there is a need for 5G, advantages of 5G networks technology, exceptional applications, Quality of Service (QoS, 5G network architecture-The MasterCore as well as hardware and software for the 5GMasterCore technology

  19. The communication of meaning in social systems

    NARCIS (Netherlands)

    Leydesdorff, L.; Franse, S.

    2009-01-01

    The sociological domain is different from the psychological one insofar as meaning can be communicated at the supra-individual level. The computation of anticipatory systems enables us to distinguish between these domains in terms of weakly and strongly anticipatory systems with a structural

  20. Communication Scheme via Cascade Chaotic Systems

    Institute of Scientific and Technical Information of China (English)

    HUA Chang-Chun; GUAN Xin-Ping

    2004-01-01

    @@ A new chaotic communication scheme is constructed. Different from the existing literature, cascade chaotic systems are employed. Two cascade modes are considered. First, we investigate the input to state cascade mode;cascade systems between different kinds of chaotic systems are considered. Then the parameter cascade case of chaotic system is studied. Under the different cases, the corresponding receivers are designed, which can succeed in recovering the former emitted signal. Simulations are performed to verify the validity of the proposed main results.

  1. Intelligent Wireless Communication System Using Cognitive Radio

    Directory of Open Access Journals (Sweden)

    Asma Amraoui

    2012-04-01

    Full Text Available The increasing demand for wireless communication introduces efficient spectrum utilization challenge. To address this challenge, cognitive radio (CR is emerged as the key technology; which enables opportunistic access to the spectrum. CR is a form of wireless communication in which a transceiver can intelligently detect which communication channels are in use and which are not, and instantly move into vacant channels while avoiding occupied ones. This optimizes the use of available radio-frequency (RFspectrum while minimizing interference to other users. In this paper, we present a state of the art onthe use of Multi Agent Systems (MAS for spectrum access using cooperation and competition to solve the problem of spectrum allocation and ensure better management. Then we propose a new approach which uses the CR for improving wireless communication for a single cognitive radio mobile terminal (CRMT.

  2. Security Problem of Communication in CORBA System

    Directory of Open Access Journals (Sweden)

    Jedrzej Byrski

    2002-01-01

    Full Text Available CORBA standard defines the mechanisms of shearing services. The key rule plays ORB (Object Request Broker which enables location of suitable server and transparent communication between client and server: This paper presents problems connected with security during communication between ORB systems. In the CORBA system the objects are identified by IOR (Interoperable Object Reference. For T CP/IP it contains IP server address, port and object key. Filtration may use such information as: type of communicate, IP address of client, object key to which client wants to access, type of operation, clients principal. In proposed implementation the firewall works as CORBA server and cooperates with half bridge. It is registered in ORB system and provides the controlling functions for entering packages by IDL interface. In the paper also the structure of filtering module is presented. Its main part is ACL (Access Control Lisa with rules of access. The performance evaluation results are also presented.

  3. Communications for Coordinative Control of Wind Power Systems

    DEFF Research Database (Denmark)

    Wei, Mu

    system control strategies for wind power integration, in order to achieve coordinative control for a secure and efficient power system. The project basically contains three main aspects: studies on DGS (Distributed Generation System) characteristics, analysis of communication technologies......, and integration of power system and communication system. For the DGS studies, the main components, such as WTs (Wind Turbines) and CHPs (Combined Head and Power), are modelled. Since WTs are sensitive to disturbances, one focus of this PhD study is the investigation of WTs characteristics; mainly covering FSIG...... (Fixed Speed Induction Generator) and DFIG (Doubly-Fed Induction Generator) based wind turbine systems. Based on the study, the critical points to stabilize FSWTs (Fixed Speed Wind Turbines), after disturbances, are determined. This demands the latency requirements on the possible control and protection...

  4. Lymphangioma communicating with the excretory system.

    Science.gov (United States)

    Pancione, L; Giacomelli, G; Moroni, M; Taraglio, G; Mecozzi, B

    2008-03-01

    Lymphangioma is a rare benign tumor caused by failure in the development of the lymphatic communicating system. The corresponding nomenclature is confusing. In recent years ''renal lymphangiectasia'' is the preferred name. Although this disease may occur in any site of the body, the neck (75%) and axillary area (20%) are the most common sites, and the kidney is occasionally involved. We report a case of lymphangioma communicating with the urinary system in a 61-year-old man diagnosed by CT scan treated with nephrectomy and histological confirmation.

  5. Transceiver and system design for digital communications

    CERN Document Server

    Bullock, Scott

    2009-01-01

    Now in a 3rd edition, this successful book provides an intuitive approach to transceiver design, allowing a broad spectrum of readers to understand the topics clearly. It covers a wide range of data link communication design techniques, including link budgets, dynamic range and system analysis of receivers and transmitters used in data link communications, digital modulation and demodulation techniques of phase-shift keyed and frequency hopped spread spectrum systems using phase diagrams, multipath, gain control, an intuitive approach to probability, jamming reduction method using various adap

  6. Review of Key Technologies of 5G Wireless Communication System

    Directory of Open Access Journals (Sweden)

    Shi Sha

    2015-01-01

    Full Text Available The 5th generation mobile communication system (5G is oriented towards a new generation of mobile communication system to the year of 2020 and beyond, and its development is still at the exploratory stage. Combining the latest trends in mobile communication development at home and abroad, in this article, we describe the key technologies of driving the 5G research direction. Furthermore, the technical innovation of 5G comes from both wireless and network technologies. In the field of wireless technologies, massive multiple-input multiple-output (MIMO, ultra-wideband spectral, ultra-dense heterogeneous networks, have already become the focus of global industry. In the field of network technologies, a new network architecture based on software-defined networking (SDN becomes the prevailing view worldwide. Additionally, there are some other potential technologies for 5G, such as NOMA, FBMC, mm Waves, and Multi-carrier technology aggregation.

  7. Future cooperative communication systems driven by social mobile networks

    DEFF Research Database (Denmark)

    Blázovics, L.; Varga, C.; Bamford, W.

    2011-01-01

    In this work we are underlining the importance of social mobile networks for upcoming cooperative communication systems. The assumption of this work is that future mobile communication systems will incorporate user cooperation, i.e. a combination of cellular access in parallel with ongoing short...... range links to the neighboring devices. It has been shown that user cooperation enables higher data rates, better spectral efficiencies, and reduces the energy consumption of the mobile unit. In this work the social mobile networks are identified to be a fertile ground to facilitate the cooperative use...... cases. By the example of the Gedda-Headz gaming community, possible links between cooperative mobile communication and social mobile networks are shown....

  8. Wireless communication system via nanoscale plasmonic antennas.

    Science.gov (United States)

    Merlo, Juan M; Nesbitt, Nathan T; Calm, Yitzi M; Rose, Aaron H; D'Imperio, Luke; Yang, Chaobin; Naughton, Jeffrey R; Burns, Michael J; Kempa, Krzysztof; Naughton, Michael J

    2016-08-24

    Present on-chip optical communication technology uses near-infrared light, but visible wavelengths would allow system miniaturization and higher energy confinement. Towards this end, we report a nanoscale wireless communication system that operates at visible wavelengths via in-plane information transmission. Here, plasmonic antenna radiation mediates a three-step conversion process (surface plasmon → photon → surface plasmon) with in-plane efficiency (plasmon → plasmon) of 38% for antenna separation 4λ0 (with λ0 the free-space excitation wavelength). Information transmission is demonstrated at bandwidths in the Hz and MHz ranges. This work opens the possibility of optical conveyance of information using plasmonic antennas for on-chip communication technology.

  9. Wireless communication system via nanoscale plasmonic antennas

    Science.gov (United States)

    Merlo, Juan M.; Nesbitt, Nathan T.; Calm, Yitzi M.; Rose, Aaron H.; D'Imperio, Luke; Yang, Chaobin; Naughton, Jeffrey R.; Burns, Michael J.; Kempa, Krzysztof; Naughton, Michael J.

    2016-08-01

    Present on-chip optical communication technology uses near-infrared light, but visible wavelengths would allow system miniaturization and higher energy confinement. Towards this end, we report a nanoscale wireless communication system that operates at visible wavelengths via in-plane information transmission. Here, plasmonic antenna radiation mediates a three-step conversion process (surface plasmon → photon → surface plasmon) with in-plane efficiency (plasmon → plasmon) of 38% for antenna separation 4λ0 (with λ0 the free-space excitation wavelength). Information transmission is demonstrated at bandwidths in the Hz and MHz ranges. This work opens the possibility of optical conveyance of information using plasmonic antennas for on-chip communication technology.

  10. Robust Stackelberg game in communication systems

    CERN Document Server

    parsaeefard, saeedeh; Sharafat, Ahmad R

    2011-01-01

    This paper studies multi-user communication systems with two groups of users: leaders which possess system information, and followers which have no system information using the formulation of Stackelberg games. In such games, the leaders play and choose their actions based on their information about the system and the followers choose their actions myopically according to their observations of the aggregate impact of other users. However, obtaining the exact value of these parameters is not practical in communication systems. To study the effect of uncertainty and preserve the players' utilities in these conditions, we introduce a robust equilibrium for Stackelberg games. In this framework, the leaders' information and the followers' observations are uncertain parameters, and the leaders and the followers choose their actions by solving the worst-case robust optimizations. We show that the followers' uncertain parameters always increase the leaders' utilities and decrease the followers' utilities. Conversely,...

  11. 3rd International Conference on Communications, Signal Processing, and Systems

    CERN Document Server

    Liang, Qilian; Wang, Wei; Zhang, Baoju; Pi, Yiming

    2015-01-01

    The Proceedings of The Third International Conference on Communications, Signal Processing, and Systems provides the state-of-art developments of communications, signal processing, and systems. This book is a collection of contributions from the conference and covers such topics as wireless communications, networks, systems, and signal processing for communications. The conference was held July 2014 in Hohhot, Inner Mongolia, China.

  12. Communications and Tracking Distributed Systems Evolution Study

    Science.gov (United States)

    Culpepper, William

    1990-01-01

    The Communications and Tracking (C & T) techniques and equipment to support evolutionary space station concepts are being analyzed. Evolutionary space station configurations and operational concepts are used to derive the results to date. A description of the C & T system based on future capability needs is presented. Included are the hooks and scars currently identified to support future growth.

  13. Manual communication systems: evolution and variation

    NARCIS (Netherlands)

    Pfau, R.; Pfau, R.; Steinbach, M.; Woll, B.

    2012-01-01

    This chapter addresses issues in the evolution and typology of manual communication systems. From a language evolution point of view, sign languages are interesting because it has been suggested that oral language may have evolved from gestural (proto)language. As far as typology is concerned, two i

  14. A system dynamics model for communications networks

    Science.gov (United States)

    Awcock, A. J.; King, T. E. G.

    1985-09-01

    An abstract model of a communications network in system dynamics terminology is developed as implementation of this model by a FORTRAN program package developed at RSRE is discussed. The result of this work is a high-level simulation package in which the performance of adaptive routing algorithms and other network controls may be assessed for a network of arbitrary topology.

  15. Transforming student learning with classroom communication systems

    CERN Document Server

    Beatty, I D

    2005-01-01

    Since 1993, the University of Massachusetts Physics Education Research Group (UMPERG) has developed curriculum and pedagogic techniques for use with classroom communication systems (CCSs) and has researched the effectiveness of CCS-based teaching. This bulletin describes how CCSs can influence "interactive pedagogy" and fundamentally transform the learning process. It includes advice drawn from lessons learned through a decade of experience.

  16. Second International Conference on Communications, Signal Processing, and Systems

    CERN Document Server

    Mu, Jiasong; Wang, Wei; Liang, Qilian; Pi, Yiming

    2014-01-01

    The Proceedings of The Second International Conference on Communications, Signal Processing, and Systems provides the state-of-art developments of Communications, Signal Processing, and Systems. The conference covered such topics as wireless communications, networks, systems, signal processing for communications. This book is a collection of contributions coming out of The Second International Conference on Communications, Signal Processing, and Systems (CSPS) held September 2013 in Tianjin, China.

  17. Packet Reordering Procedure with Ubiquous Communication Systems

    Directory of Open Access Journals (Sweden)

    Giridhar Akula

    2012-11-01

    Full Text Available Satellite links are going to play a vital role in the deployment of ubiquous broad band systems. Non- Geostationary (NGEO satellite communication systems are more advantageous than terrestrial satellites. This paper presents an exchange of information on cooperation status among neiboring satellites. The new explicit load balancing scheme is used to avoid congestion and packet drops at the satellite. A TTL based algorithm is used for packet reordering.

  18. Emoticon recommendation system for effective communication

    OpenAIRE

    Urabe, Yuki; Rzepka, Rafal; Araki, Kenji

    2013-01-01

    The existence of social media has made computer- mediated communication more widespread among users around the world. This paper describes the development of an emoticon recommendation system that allows users to express their feelings with their input. In order to develop this system, an innovative emoticon database consisting of a table of emoticons with points expressed from each of 10 distinctive emotions was constructed. An evaluation experiment showed that 71.3% of user-selected emotico...

  19. Communication and tracking system evolution study

    Science.gov (United States)

    Culpepper, William

    1990-01-01

    The communications and tracking (C&T) techniques and equipment to support evolutionary space station concepts are being analyzed. Evolutionary space station configurations and operational concepts were used in the analysis to derive the results to date. A description of the C&T system based on future capability needs is presented. Included are the 'hooks and scars' currently identified to support the future growth. Technology transparency and impact of growth on other systems are also addressed.

  20. Analysis of Unmmanned Air Vehicles Communication Systems

    Directory of Open Access Journals (Sweden)

    Darius Rudinskas

    2011-04-01

    Full Text Available The analyzed questions of information security transferable by the radio connection link are presented in this article. This safety it is especially important for design of unmanned air vehicles (UAV and for other remote control vehicles. Also questions about UAV communication systems structure, security treats of radio connection system, possible menaces for secure information transferring, security and integrity are discussed in our presentation. Article in Lithuanian

  1. Energy efficiency in wireless communication systems

    Science.gov (United States)

    Caffrey, Michael Paul; Palmer, Joseph McRae

    2012-12-11

    Wireless communication systems and methods utilize one or more remote terminals, one or more base terminals, and a communication channel between the remote terminal(s) and base terminal(s). The remote terminal applies a direct sequence spreading code to a data signal at a spreading factor to provide a direct sequence spread spectrum (DSSS) signal. The DSSS signal is transmitted over the communication channel to the base terminal which can be configured to despread the received DSSS signal by a spreading factor matching the spreading factor utilized to spread the data signal. The remote terminal and base terminal can dynamically vary the matching spreading factors to adjust the data rate based on an estimation of operating quality over time between the remote terminal and base terminal such that the amount of data being transmitted is substantially maximized while providing a specified quality of service.

  2. Multi-aperture digital coherent combining for free-space optical communication receivers.

    Science.gov (United States)

    Geisler, David J; Yarnall, Timothy M; Stevens, Mark L; Schieler, Curt M; Robinson, Bryan S; Hamilton, Scott A

    2016-06-13

    Space-to-ground optical communication systems can benefit from reducing the size, weight, and power profiles of space terminals. One way of reducing the required power-aperture product on a space platform is to implement effective, but costly, single-aperture ground terminals with large collection areas. In contrast, we present a ground terminal receiver architecture in which many small less-expensive apertures are efficiently combined to create a large effective aperture while maintaining excellent receiver sensitivity. This is accomplished via coherent detection behind each aperture followed by digitization. The digitized signals are then combined in a digital signal processing chain. Experimental results demonstrate lossless coherent combining of four lasercom signals, at power levels below 0.1 photons/bit/aperture.

  3. 17 CFR 230.166 - Exemption from section 5(c) for certain communications in connection with business combination...

    Science.gov (United States)

    2010-04-01

    ...) for certain communications in connection with business combination transactions. 230.166 Section 230... only to communications relating to business combinations. The exemption does not apply to...) Communications. In a registered offering involving a business combination transaction, any communication made in...

  4. Electronic communication channel within the patient data management system improves internal communication in the ICU.

    Science.gov (United States)

    Väisänen, Paula; Holopainen, Jaana

    2006-01-01

    The aim of this study was to improve the internal communication within the intensive care unit of the Kuopio University Hospital. We developed an intranet based internal communication channel within the patient data management system and studied the effectiveness of this system in improving communication in the ICU. The hypothesis was that the communication difficulties caused by the structure of the unit, large personnel and work schedule (three separate shifts) could be reduced by supplementing oral communication by this intranet based system. The results clearly indicate that this type of system can significantly improve communication within our unit.

  5. Seamless integrated network system for wireless communication systems

    NARCIS (Netherlands)

    Wu, Gang; Mizuno, Mitsuhiko; Hase, Yoshihiro; Havinga, Paul J.M.

    2006-01-01

    To create a network that connects a plurality of wireless communication systems to create optimal systems for various environments, and that seamlessly integrates the resulting systems together in order to provide more efficient and advanced service in general. A network system that can seamlessly i

  6. Seamless integrated network system for wireless communication systems

    NARCIS (Netherlands)

    Wu, Gang; Mizuno, Mitsuhiko; Hase, Yoshihiro; Havinga, Paul J.M.

    2002-01-01

    To create a network that connects a plurality of wireless communication systems to create optimal systems for various environments, and that seamlessly integrates the resulting systems together in order to provide more efficient and advanced service in general. A network system that can seamlessly i

  7. Communicating embedded systems software and design

    CERN Document Server

    Jard, Claude

    2013-01-01

    The increased complexity of embedded systems coupled with quick design cycles to accommodate faster time-to-market requires increased system design productivity that involves both model-based design and tool-supported methodologies. Formal methods are mathematically-based techniques and provide a clean framework in which to express requirements and models of the systems, taking into account discrete, stochastic and continuous (timed or hybrid) parameters with increasingly efficient tools. This book deals with these formal methods applied to communicating embedded systems by presenting the

  8. Distributed algorithms over communicating membrane systems.

    Science.gov (United States)

    Ciobanu, Gabriel

    2003-07-01

    This paper presents fundamental distributed algorithms over membrane systems with antiport carriers. We describe distributed algorithms for collecting and dispersing information, leader election in these systems, and the mutual exclusion problem. Finally, we consider membrane systems producing correct results despite some failures at some of the components or the communication links. We show that membrane systems with antiport carriers provide an appropriate model for distributed computing, particularly for message-passing algorithms interpreted here as membrane transport in both directions, namely when two chemicals behave as input and output messages and pass the membranes in both directions using antiport carriers.

  9. Systemic combination treatment for psoriasis: a review

    DEFF Research Database (Denmark)

    Jensen, Peter; Skov, Lone; Zachariae, Claus

    2010-01-01

    exist for the use of systemic combination therapy. Therefore, our aim was to review the current literature on systemic anti-psoriatic combination regimens. We searched PubMed and identified 98 papers describing 116 studies (23 randomized) reporting on the effect of various systemic combination...

  10. Communication System for CIMS Application Integration Platform

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    CIMS has seen the growth of multiple incompatible hardware architectur es, each architecture supporting several incompatible operating systems, and eac h platform operating with various incompatible development tools (e.g., programm ing language compilers, DBMS, etc.) and one or more incompatible graphic user in terfaces. Also, the growth of the Internet, the World-Wide Web, has introduced new dimensio ns of complexity into the development process. All of these must be dealt with a s the application is made workable in a distributed client-server environment. This paper outlines the architecture of a communication system for the CIMS appl ication integration platform. The communication system makes possible the reque st for service across heterogeneous platforms and networks, and provides some co mmon solutions to issues common to CIMS applications.

  11. Security aspects of RFID communication systems

    Science.gov (United States)

    Bîndar, Valericǎ; Popescu, Mircea; Bǎrtuşicǎ, Rǎzvan; Craciunescu, Razvan; Halunga, Simona

    2015-02-01

    The objective of this study is to provide an overview of basic technical elements and security risks of RFID communication systems and to analyze the possible threats arising from the use of RFID systems. A number of measurements are performed on a communication system including RFID transponder and the tag reader, and it has been determined that the uplink signal level is 62 dB larger than the average value of the noise at the distance of 1m from the tag, therefore the shielding effectiveness has to exceed this threshold. Next, the card has been covered with several shielding materials and measurements were carried, under similar conditions to test the recovery of compromising signals. A very simple protection measure to prevent unauthorized reading of the data stored on the card has been proposed, and some electromagnetic shielding materials have been proposed and tested.

  12. Compositional Memory Systems for Multimedia Communicating Tasks

    CERN Document Server

    Molnos, A M; Cotofana, S D; Van Eijndhoven, J T J

    2011-01-01

    Conventional cache models are not suited for real-time parallel processing because tasks may flush each other's data out of the cache in an unpredictable manner. In this way the system is not compositional so the overall performance is difficult to predict and the integration of new tasks expensive. This paper proposes a new method that imposes compositionality to the system?s performance and makes different memory hierarchy optimizations possible for multimedia communicating tasks when running on embedded multiprocessor architectures. The method is based on a cache allocation strategy that assigns sets of the unified cache exclusively to tasks and to the communication buffers. We also analytically formulate the problem and describe a method to compute the cache partitioning ratio for optimizing the throughput and the consumed power. When applied to a multiprocessor with memory hierarchy our technique delivers also performance gain. Compared to the shared cache case, for an application consisting of two jpeg ...

  13. Calendar systems and communication of deaf-blind children

    Directory of Open Access Journals (Sweden)

    Jablan Branka

    2012-01-01

    Full Text Available The aim of this paper is to explain the calendar systems and their role in teaching deaf-blind children. Deaf-blind persons belong to a group of multiple disabled persons. This disability should not be observed as a simple composite of visual and hearing impairments, but as a combination of sensory impairments that require special assistance in the development, communication and training for independent living. In our environment, deaf-blind children are being educated in schools for children with visual impairments or in schools for children with hearing impairments (in accordance with the primary impairment. However, deaf-blind children cannot be trained by means of special programs for children with hearing impairment, visual impairment or other programs for students with developmental disabilities without specific attention required by such a combination of sensory impairments. Deaf-blindness must be observed as a multiple impairment that requires special work methods, especially in the field of communication, whose development is severely compromised. Communication skills in deaf-blind people can be developed by using the calendar systems. They are designed in such a manner that they can be easily attainable to children with various sensory impairments. Calendars can be used to encourage and develop communication between adult persons and a deaf-blind child.

  14. Flip-OFDM for Unipolar Communication Systems

    CERN Document Server

    Fernando, Nirmal; Viterbo, Emanuele

    2011-01-01

    Unipolar communications systems can transmit information using only real and positive signals. This includes a variety of physical channels ranging from optical (fiber or free-space), to RF wireless using amplitude modulation with non-coherent reception, to baseband single wire communications. Unipolar OFDM techniques enable to efficiently compensate frequency selective distortion in the unipolar communication systems. One of the leading examples of unipolar OFDM is asymmetric clipped optical OFDM (ACO-OFDM) originally proposed for optical communications. Flip-OFDM is an alternative approach that was proposed in a patent, but its performance and full potentials have never been investigated in the literature. In this paper, we first compare Flip-OFDM and ACO-OFDM, and show that both techniques have the same performance but different complexities (Flip-OFDM offers 50% saving). We then propose a new detection scheme, which enables to reduce the noise at the Flip-OFDM receiver by almost 3dB. The analytical perfor...

  15. Communications System for Down-Hole Measurements

    Directory of Open Access Journals (Sweden)

    Mijarez-Castro Rito

    2013-12-01

    Full Text Available Progressively deeper and hotter oil wells have driven design modification that enhances the performance in sensors and downhole electronic instruments. Oil reservoirs in Mexico are located at mean depths of 6,000 m; as a consequence, the requirements for measuring thermodynamic and geophysical parameters are challenging. This paper describes a bidirectional communication system that exchanges data from a down-hole high pressure and high temperature (HP/HT measurement tool to the surface installation. The communication medium is a 7 km mono-conductor 1K22 logging cable used also as a power supply transmission line. The system consists of a proprietary downhole measurement tool, composed of a HT/HP sensor and a high temperature DSP-based electronic device, and a data acquisition equipment located in the surface installation. The system employs a communication algorithm that automatically changes the carrier frequency of the modulation technique employed, to avoid issues derived from noise interference, cable attenuation and thermal drift of the front end passive elements. The laboratory tests results provide a firm basis for testing and evaluating the system in the field.

  16. Energy Efficiency of MIMO-OFDM Communication System

    Directory of Open Access Journals (Sweden)

    K.Swathi

    2014-09-01

    Full Text Available With the ever increasing number of subscribers and their seemingly “greedy” demands for high-data-rate services, the next generation networks will have to provide global connectivity to ensure success. So the combination of multiple-input multiple-output (MIMO signal processing with orthogonal frequency division multiplexing (OFDM is regarded as a promising solution for enhancing the data rates of next-generation wireless communication systems operating in frequency-selective fading environments. Therefore hybrid architecture between terrestrial and satellite networks based on MIMO-OFDM with frequency reuse is employed here. However, this frequency reuse introduces severe co-channel interference (CCI at the satellite end. To mitigate CCI, we propose an OFDM based adaptive beamformer implemented on-board the satellite with pilot reallocation at the transmitter side. The system performance is simulated by using the software MATLAB, the experimental result shows that the MIMO-OFDM communication system has better performance when compared.

  17. The Combination of Business English Teaching with Communicative Approach

    Institute of Scientific and Technical Information of China (English)

    张莉

    2010-01-01

    With globalization,Business English(BE)has developed fast in China.As Communicative Language Teaching(CLT)has been popular in language teaching,many scholars have engaged in the integration of CLT into Business English Teaching(BET).This paper tries to evaluate its implementation and aims to promote the BET through finding the success and limitations through evaluation.

  18. AN OVERVIEW OF VISIBLE LIGHT COMMUNICATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Taner Cevik

    2015-11-01

    Full Text Available Visible Light Communication (VLC has gained great interest in the last decade due to the rapid developments in Light Emitting Diodes (LEDs fabrication. Efficiency, durability and long life span of LEDs make them a promising residential lighting equipment as well as an alternative cheap and fast data transfer equipment. Appliance of visual light in data communication by means of LEDs has been densely searched in academia. In this paper, we explore the fundamentals and challenges of indoor VLC systems. Basics of optical transmission such as transmitter, receiver, and links are investigated. Moreover, characteristics of channel models in indoor VLC systems are identified and theoretical details about channel modelling are presented in detail.

  19. Toward a Gigabit Wireless Communications System

    CERN Document Server

    Rakotondrainibe, Lahatra; Zaharia, Gheorghe; Zein, Ghaïs El

    2009-01-01

    This paper presents the design and the realization of a hybrid wireless Gigabit Ethernet indoor communications system operating at 60 GHz. As the 60 GHz radio link operates only in a single-room configuration, an additional Radio over Fiber (RoF) link is used to ensure the communications within all the rooms of a residential environment. The system uses low complexity baseband processing modules. A byte synchronization technique is designed to provide a high value of the preamble detection probability and a very small value of the false detection probability. Conventional RS (255, 239) encoder and decoder are used for channel forward error correction (FEC). The FEC parameters are determined by the tradeoff between higher coding gain and hardware complexity. The results of bit error rate measurements at 875 Mbps are presented for various antennas configurations.

  20. Radio propagation for space communications systems

    Science.gov (United States)

    Ippolito, L. J.

    1981-01-01

    This paper presents a review of the most recent information on the effects of the earth's atmosphere on space communications systems. Models and techniques used in the prediction of atmospheric effects as influenced by frequency, geography, elevation angle, and type of transmission are discussed. Recent data on performance characteristics obtained from direct measurements on satellite links operating to above 30 GHz are reviewed. Particular emphasis is placed on the effects of precipitation on the earth-space path, including rain attenuation, and rain and ice-particle depolarization. Sky noise, antenna gain degradation, scintillations, and bandwidth coherence are also discussed. The impact of the various propagation factors on communications system design criteria is presented. These criteria include link reliability, power margins, noise contributions, modulation and polarization factors, channel crosstalk, error-rate, and bandwidth limitations.

  1. Ship-Shore Packet Switched Communications System.

    Science.gov (United States)

    1986-06-01

    a fatal flaw for sea service communications. This instability is described in several texts [ Stallings , 85; Tanenbaum, 81]. 68 b. Token Systems Again... decompressor in the data path. otherwise, the decompression algorithm would compound errors and make different instances of errored packets different lengths...Further detail may be found in several sources including listed references [ Stallings , 85]. DoD’s seminal ARPANET work predated the ISO model and evolved a

  2. Electronic circuits for communications systems: A compilation

    Science.gov (United States)

    1972-01-01

    The compilation of electronic circuits for communications systems is divided into thirteen basic categories, each representing an area of circuit design and application. The compilation items are moderately complex and, as such, would appeal to the applications engineer. However, the rationale for the selection criteria was tailored so that the circuits would reflect fundamental design principles and applications, with an additional requirement for simplicity whenever possible.

  3. Application of Wireless Communication Technology in Integrated DNI System

    Institute of Scientific and Technical Information of China (English)

    WANG Gang; WU Bin; ZHANG Min; XIA Xiao-zhen

    2006-01-01

    A communication method of integrated DNC(direct numerical control) system is introduced and a new system based on wireless technology is presented. Advantages of wireless communication are described. The scheme of actual communication system is designed, and the integrated system and its function are introduced.

  4. 46 CFR 121.602 - Internal communications systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Internal communications systems. 121.602 Section 121.602... MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 121.602 Internal communications systems. (a) A vessel equipped with pilothouse control must have a fixed means of...

  5. 46 CFR 184.602 - Internal communications systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Internal communications systems. 184.602 Section 184.602... TONS) VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 184.602 Internal communications systems. (a) A vessel equipped with pilothouse control must...

  6. The Peace System - As a self-referential communication system

    Directory of Open Access Journals (Sweden)

    Gorm Harste

    2013-11-01

    Full Text Available Peace communication as diplomatic communication is an often neglected phenomenon in social and political theory that concerns problems of international order, justice and peace. Political philosophy seldom embarks on the theme with more than a few comments. Yet, throughout history, diplomacy has a strong record not only for negotiations but also for social learning processes about communication codes. Many codes of respect, trust, expression and listening have a top-down history from aristocratic circles to broader social layers. However, the article argues that communication codes of peace developed in opposition to violence and war exactly when they transgress dividing lines allowing for cross-cultural and even cross-stratified communication. The article’s main point is to describe how such communication codes about peace and diplomacy can be described in recent social theory of communication, and to get some added value in this respect, Niklas Luhmann’s theory of self-referential communication systems has been applied.

  7. The interactive evolution of human communication systems.

    Science.gov (United States)

    Fay, Nicolas; Garrod, Simon; Roberts, Leo; Swoboda, Nik

    2010-04-01

    This paper compares two explanations of the process by which human communication systems evolve: iterated learning and social collaboration. It then reports an experiment testing the social collaboration account. Participants engaged in a graphical communication task either as a member of a community, where they interacted with seven different partners drawn from the same pool, or as a member of an isolated pair, where they interacted with the same partner across the same number of games. Participants' horizontal, pair-wise interactions led "bottom up" to the creation of an effective and efficient shared sign system in the community condition. Furthermore, the community-evolved sign systems were as effective and efficient as the local sign systems developed by isolated pairs. Finally, and as predicted by a social collaboration account, and not by an iterated learning account, interaction was critical to the creation of shared sign systems, with different isolated pairs establishing different local sign systems and different communities establishing different global sign systems.

  8. Algorithm of communication network reliability combining links, nodes and capacity

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The conception of the normalized reliability index weighted by capacity is introduced, which combing the communication capacity, the reliability probability of exchange nodes and the reliability probability of the transmission links,in order to estimate the reliability performance of communication network comprehensively and objectively. To realize the full algebraic calculation, the key problem should be resolved, which is to find an algorithm to calculate all the routes between nodes of a network. A kind of logic algebraic algorithm of network routes is studied and based on this algorithm,the full algebraic algorithm of normalized reliability index weighted by capacity is studied. For this algorithm, it is easy to design program and the calculation of reliability index is finished, which is the foundation of the comprehensive and objective estimation of comnunication networks. The calculation procedure of the algorithm is introduced through typical ex amples and the results verify the algorithm.

  9. Combining Natural Human-Computer Interaction and Wireless Communication

    Directory of Open Access Journals (Sweden)

    Ştefan Gheorghe PENTIUC

    2011-01-01

    Full Text Available In this paper we present how human-computer interaction can be improved by using wireless communication between devices. Devices that offer a natural user interaction, like the Microsoft Surface Table and tablet PCs, can work together to enhance the experience of an application. Users can use physical objects for a more natural way of handling the virtual world on one hand, and interact with other users wirelessly connected on the other. Physical objects, that interact with the surface table, have a tag attached to them, allowing us to identify them, and take the required action. The TCP/IP protocol was used to handle the wireless communication over the wireless network. A server and a client application were developed for the used devices. To get a wide range of targeted mobile devices, different frameworks for developing cross platform applications were analyzed.

  10. One exhibition, many goals. Combining scientific research and risk communication

    Science.gov (United States)

    Charrière, Marie; Bogaard, Thom; Junier, Sandra; Malet, Jean-Philippe; Mostert, Erik

    2015-04-01

    How effective is visual communication to increase awareness of natural hazards and risks? To answer this research question, we developed a research design that was at the same time an experimental setting and an actual communication effort. Throughout the full length of the 2-years project held in the Ubaye valley (southeastern France), we collaborated with local and regional stakeholders (politicians and technicians). During a consultation phase, the communication context was determined, the audience of the project was defined and finally the testing activity-communication effort was determined. We were offered the opportunity to design an exhibition for the local public library. In a consultation phase that corresponded to the design of the exhibition, the stakeholders contributed to its content as well as helping with the funding of the exhibition. Finally, during the experimentation phase, the stakeholders participated in advertising the activity, gathering of participants and designing the scientific survey. In order to assess the effects of the exhibition on risk awareness, several groups of children, teenagers and adults were submitted to a research design, consisting of 1) a pre-test, 2) the visit of the exhibition and 3) a post-test similar to the pre-test. In addition, the children answered a second post-test 3 months after the visit. Close ended questions addressed the awareness indicators mentioned in the literature, i.e. worry level, previous experiences with natural hazards events, exposure to awareness raising, ability to mitigate/respond/prepare, attitude to risk, and demographics. In addition, the post-test included several satisfaction questions concerning the visual tools displayed in the exhibition. A statistical analysis of the changes between the pre- and post- tests (paired t-test, Wilcoxon signed-rank test and bootstrapping) allowed to verify whether the exhibition had an impact on risk awareness or not. In order to deduce which variable

  11. Multi-Modal Local Sensing and Communication for Collective Underwater Systems

    CERN Document Server

    Kernbach, Serge; Sutantyo, Donny

    2011-01-01

    This paper is devoted to local sensing and communication for collective underwater systems used in networked and swarm modes. It is demonstrated that a specific combination of modal and sub-modal communication, used simultaneously for robot-robot and robot-object detection, can create a dedicated cooperation between multiple AUVs. These technologies, platforms and experiments are shortly described, and allow us to make a conclusion about useful combinations of different signaling approaches for collective underwater systems.

  12. A Novel Concatenated Chaotic Communication System

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A strategy for a novel concatenated chaotic communication system is presented. The transmitter system comprises chaotic turbo encoder and logistic CSK block in a serially concatenated form. Chaotic turbo code is capable of reducing bit error rate (BER) of the chaotic system in the AWGN channel. Through the chaotic turbo encoder, the coded sequence, which has quasi-chaotic properties, will be transmitted into the logistic CSK block. Having a very sensitive dependence on initial conditions of the map, the logistic CSK block can also be taken as the chaotic authentication method. The receiver, which has logistic demodulation block and chaotic decoder, is a linear asymptotic approximation to the inverse of the transmitter system. A chaotic iterative soft-decision decoding algorithm is also developed based on conventional maximum A posteriori decoding algorithm. At last, a two-step authentication method of this chaotic system is also presented.

  13. CSR Communication in the Romanian Banking System

    Directory of Open Access Journals (Sweden)

    Georgiana-Loredana Frecea

    2016-01-01

    Full Text Available The CSR dimensions of the Romanian banking sector should be linked to the key role of thefinancial enterprises, as primary intermediaries on the global market. This position results fromtheir ability to rapidly spread positive or negative economic circumstances on the other markets,influencing the financial sustainability of the entire world as a whole. Various differences has beennoted in the Romanian banking system due to the importance attached to representativestakeholders and to the CSR communication tools. Starting from the relationship betweenstakeholders and the reputational value, this paper aims to establish a valuable approach to theexisting connections between the main stakeholders and the CSR communication strategies inRomania. The focus is on the efforts to regain the trust in banks through developing the corporateidentities in accordance with the CSR principles.

  14. Power Line Communication Based Home Security System

    Directory of Open Access Journals (Sweden)

    Sankalp N. Gujar

    2013-11-01

    Full Text Available The aim of this paper is to demonstrate the use of Power line (A.C mains based security system i.e. developing the hardware for a microcontroller module that is to be interfaced to sensors which will detect breaches in security and developing a power line communication modem for sending/receiving data from the microcontroller modules over the power line. As soon as any one of the sensors in an establishment is triggered, the microcontroller will send data to the power line communication modem over UART. The modem will then convert the incoming data into a packet, modulate it using ASK and transmit it over the power line through the coupling circuit. The modem at the security cabin will demodulate this packet and send it to the microcontroller over UART. The microcontroller then activates the alarm and displays the location and nature of the breach on the display

  15. 47 CFR 90.465 - Control of systems of communication.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Control of systems of communication. 90.465... SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control § 90.465 Control of systems of communication. (a) Depending on design considerations, control of a system of communication may be exercised in...

  16. Rube Goldberg Salad System: Teaching Systems Theory in Communication

    Science.gov (United States)

    Linabary, Jasmine R.; Long, Ziyu; Mouton, Ashton; Rao, Ranjani L.; Buzzanell, Patrice M.

    2016-01-01

    Systems theory has been a staple in organizational communication textbooks since the field's inception (Miller, 2015; Poole, 2014). Nevertheless, the authors' classroom experiences have revealed that systems theory may not seem applicable to students due to its complicated nature. While examples and cases can help students make sense of the…

  17. Rube Goldberg Salad System: Teaching Systems Theory in Communication

    Science.gov (United States)

    Linabary, Jasmine R.; Long, Ziyu; Mouton, Ashton; Rao, Ranjani L.; Buzzanell, Patrice M.

    2016-01-01

    Systems theory has been a staple in organizational communication textbooks since the field's inception (Miller, 2015; Poole, 2014). Nevertheless, the authors' classroom experiences have revealed that systems theory may not seem applicable to students due to its complicated nature. While examples and cases can help students make sense of the…

  18. Diablo Canyon plant information management system and integrated communication system

    Energy Technology Data Exchange (ETDEWEB)

    Stanley, J.W.; Groff, C.

    1990-06-01

    The implementation of a comprehensive maintenance system called the plant information management system (PIMS) at the Diablo Canyon plant, together with its associated integrated communication system (ICS), is widely regarded as the most comprehensive undertaking of its kind in the nuclear industry. This paper provides an overview of the program at Diablo Canyon, an evaluation of system benefits, and highlights the future course of PIMS.

  19. Strategies for Dense Optical CDMA Communication Systems

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-bao; LIN Jin-tong

    2005-01-01

    In this paper,we have formulated a strategy that the limited available code sequences in pure Direct-Sequence(DS)or Frequency-Hopping(FH)system can be reused to realize dense optical CDMA:the strategy of novel hybrid DS/FH system.In which,the case that there are n users employing the same FH pattern but different DS code patterns is considered.On the condition that the impact of channel noises is neglected,the upper bound probability of error is evaluated based on the stationary random process theory.The results show that the hybrid system is suitable for Dense Optical CDMA(DOCDMA)communication.Moreover,the problems such as the link-impairment,dispersion of group velocity,etc.in the pure(DS or FH)system can be solved effectively.

  20. Systemic combination treatment for psoriasis: a review

    DEFF Research Database (Denmark)

    Jensen, Peter; Skov, Lone; Zachariae, Claus

    2010-01-01

    Psoriasis is a chronic inflammatory skin disease, which affects approximately 2.6% of the population in Northern Europe and Scandinavia. In order to achieve disease control, combinations of systemic treatments are sometimes needed for variable time periods. However, no evidence-based guidelines...... exist for the use of systemic combination therapy. Therefore, our aim was to review the current literature on systemic anti-psoriatic combination regimens. We searched PubMed and identified 98 papers describing 116 studies (23 randomized) reporting on the effect of various systemic combination...

  1. Systemic Approach to Human Communication: A Synthesis of the Works of Ruesch, Bateson, Watzlawick, and Haley.

    Science.gov (United States)

    Arnett, Ronald C.

    The purpose of this article is to bring together the work of Jurgen Ruesch, Gregory Bateson, Paul Watzlawick, and Jay Haley in order to reveal their combined contribution to a systemic understanding of communicative behavior. Emphasis is upon the interactional and circular pattern of human communication, rather than on the linear, or cause/effect,…

  2. Systemic Approach to Human Communication: A Synthesis of the Works of Ruesch, Bateson, Watzlawick, and Haley.

    Science.gov (United States)

    Arnett, Ronald C.

    The purpose of this article is to bring together the work of Jurgen Ruesch, Gregory Bateson, Paul Watzlawick, and Jay Haley in order to reveal their combined contribution to a systemic understanding of communicative behavior. Emphasis is upon the interactional and circular pattern of human communication, rather than on the linear, or cause/effect,…

  3. Chaos communication based on synchronization of discrete-time chaotic systems

    Institute of Scientific and Technical Information of China (English)

    Lu Jun-Guo; Xi Yu-Geng

    2005-01-01

    A novel chaos communication method is proposed based on synchronization of discrete-time chaotic systems. This method uses a full-order state observer to achieve synchronization and secure communication between the transmitter and the receiver. Further, we present a multiple-access chaotic digital communication method by combining the observer with the on-line least square method. Simulation results are also given for illustration.

  4. Schedulability-Driven Communication Synthesis for Time Triggered Embedded Systems

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    2006-01-01

    We present an approach to static priority preemptive process scheduling for the synthesis of hard real-time distributed embedded systems where communication plays an important role. The communication model is based on a time-triggered protocol. We have developed an analysis for the communication...... delays proposing four different message scheduling policies over a time-triggered communication channel. Optimization strategies for the synthesis of communication are developed, and the four approaches to message scheduling are compared using extensive experiments...

  5. Light Fidelity (Li-Fi) Based Indoor Communication System

    OpenAIRE

    Farooq Aftab; Muhammad Nafees Ulfat khan; Shahzad Ali

    2016-01-01

    Indoor wireless communication is an essential part of next generation wireless communication system.For an indoor communication number of users and their device are increasing very rapidly so as a result capacity of frequency spectrum to accommodate further users in future is limited and also it would be difficult for service providers to provide more user reliable and high speed communication so this short come can be solve in future by using Li-Fi based indoor communication syst...

  6. Schedulability-Driven Communication Synthesis for Time Triggered Embedded Systems

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    2006-01-01

    We present an approach to static priority preemptive process scheduling for the synthesis of hard real-time distributed embedded systems where communication plays an important role. The communication model is based on a time-triggered protocol. We have developed an analysis for the communication...... delays proposing four different message scheduling policies over a time-triggered communication channel. Optimization strategies for the synthesis of communication are developed, and the four approaches to message scheduling are compared using extensive experiments...

  7. Schedulability-Driven Communication Synthesis for Time Triggered Embedded Systems

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    2004-01-01

    We present an approach to static priority preemptive process scheduling for the synthesis of hard real-time distributed embedded systems where communication plays an important role. The communication model is based on a time-triggered protocol. We have developed an analysis for the communication...... delays with four different message scheduling policies over a time-triggered communication channel. Optimization strategies for the synthesis of communication are developed, and the four approaches to message scheduling are compared using extensive experiments....

  8. Schedulability-Driven Communication Synthesis for Time Triggered Embedded Systems

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    1999-01-01

    We present an approach to static priority preemptive process scheduling for the synthesis of hard real-time distributed embedded systems where communication plays an important role. The communication model is based on a time-triggered protocol. We have developed an analysis for the communication...... delays proposing four different message scheduling policies over a time-triggered communication channel. Optimization strategies for the synthesis of communication are developed, and the four approaches to message scheduling are compared using extensive experiments....

  9. National Communications System: Ensuring Essential Communications for the Homeland

    Science.gov (United States)

    2002-01-01

    small businesses and PBXs operated by the hospitality industry (hotels and motels). Commonly encountered problems include the need to deposit coins...industry groups, such as the American Public Communications Council and hospitality industry organizations and associations, to raise awareness of GETS

  10. Antenna technology for advanced mobile communication systems

    Science.gov (United States)

    Rammos, Emmanuel; Roederer, Antoine; Rogard, Roger

    1988-01-01

    The onboard antenna front end is the key subsystem conditioning configuration and performance of mobile communication satellites. The objectives of this paper are to demonstrate this key role and to review L-band satellite antenna technology for earth coverage and regional applications. Multibeam arrays are first discussed, then unfurlable and inflatable reflector antennas are described. These technologies are now qualified in Europe for future mobile systems, for which the optimum choice of antenna technology has been found to be the key to efficient use of spectrum and power resources.

  11. Deployable Propulsion, Power and Communications Systems for Solar System Exploration

    Science.gov (United States)

    Johnson, L.; Carr, J.; Boyd, D.

    2017-01-01

    NASA is developing thin-film based, deployable propulsion, power, and communication systems for small spacecraft that could provide a revolutionary new capability allowing small spacecraft exploration of the solar system. By leveraging recent advancements in thin films, photovoltaics, and miniaturized electronics, new mission-level capabilities will be enabled aboard lower-cost small spacecraft instead of their more expensive, traditional counterparts, enabling a new generation of frequent, inexpensive deep space missions. Specifically, thin-film technologies are allowing the development and use of solar sails for propulsion, small, lightweight photovoltaics for power, and omnidirectional antennas for communication.

  12. Random digital encryption secure communication system

    Science.gov (United States)

    Doland, G. D. (Inventor)

    1982-01-01

    The design of a secure communication system is described. A product code, formed from two pseudorandom sequences of digital bits, is used to encipher or scramble data prior to transmission. The two pseudorandom sequences are periodically changed at intervals before they have had time to repeat. One of the two sequences is transmitted continuously with the scrambled data for synchronization. In the receiver portion of the system, the incoming signal is compared with one of two locally generated pseudorandom sequences until correspondence between the sequences is obtained. At this time, the two locally generated sequences are formed into a product code which deciphers the data from the incoming signal. Provision is made to ensure synchronization of the transmitting and receiving portions of the system.

  13. System 80+ D-RAP, a communication tool

    Energy Technology Data Exchange (ETDEWEB)

    Siegmann, E.R.; Mody, A.A.

    1994-12-31

    The purpose of {open_quotes}RAP{close_quotes} music is to communicate, and the purpose of D-RAP is to foster communication between the probabilistic risk assessment (PRA) group, designers, and the future combined operating license (COL) applicant. This is to ensure that the design is self-consistent and integrated with the procurement process. The designer reliability assurance program (D-RAP) is the first part of the RAP. The goals of the D-RAP are to have risk-significant systems, structures, and components (SSCs) identified and considered in the detail design and procurement phases and to maintain consistency between PRA and design. Plant safety is maintained throughout the design phase, and pertinent information is passed on to the COL applicant. The operations RAP (O-RAP) covers the plant operation and maintenance.

  14. A novel fiber audio transmission system for secure communication

    Institute of Scientific and Technical Information of China (English)

    SU Ke; JIA Bo

    2005-01-01

    A new,simple and efficient fiber audio transmission method for the long distance secure communication is presented, which performs signal modulation by the strain-optic effects and signal demodulation by the all-fiber interferometer. The interferometer is a truly path-matched device, which eliminates much of the undesirable noise by combining the reference and the sensing arms within the same optical fiber. The sinusoidal signals adopted in the experiment are in a frequency range of 300 HZ-3 400 HZ and of the multi-frequency, and the system shows good capabilities, robust security and maintenance of audio integrity. The device may be applicable in the field of point to point secure communication of 40 kilometer long transmission range.

  15. Risk communication strategy development using the aerospace systems engineering process

    Science.gov (United States)

    Dawson, S.; Sklar, M.

    2004-01-01

    This paper explains the goals and challenges of NASA's risk communication efforts and how the Aerospace Systems Engineering Process (ASEP) was used to map the risk communication strategy used at the Jet Propulsion Laboratory to achieve these goals.

  16. Towards 5th Generation Wireless Communication Systems

    Institute of Scientific and Technical Information of China (English)

    Nicola Marchetti

    2015-01-01

    This paper introduces the general landscape of next⁃generation wireless communication systems (5G), including the impetus and requirements of 5G and the candidate technologies that might help 5G achieve its goals. The following areas, which the author considers particularly relevant, are discussed: detection of and access to free spectrum over bands of a heterogeneous nature, ex⁃treme densification of networks (massive base station deployments), extreme increase in the number of antennas in base station ar⁃rays and their interaction with a novel waveform, integration of both wireless and optical sides of telecom networks, and study of wireless networks from the perspective of complex systems science. The author discusses recent research conducted by his team in each of these research areas.

  17. Odyssey, an optimized personal communications satellite system

    Science.gov (United States)

    Rusch, Roger J.

    Personal communications places severe demands on service providers and transmission facilities. Customers are not satisfied with the current levels of service and want improvements. Among the characteristics that users seek are: lower service rates, hand held convenience, acceptable time delays, ubiquitous service, high availability, reliability, and high quality. The space industry is developing commercial space systems for providing mobile communications to personal telephones. Provision of land mobile satellite service is fundamentally different from the fixed satellite service provided by geostationary satellites. In fixed service, the earth based antennas can depend on a clear path from user to satellite. Mobile users in a terrestrial environment commonly encounter blockage due to vegetation, terrain or buildings. Consequently, high elevation angles are of premium value. TRW studied the issues and concluded that a Medium Earth Orbit constellation is the best solution for Personal Communications Satellite Service. TRW has developed Odyssey, which uses twelve satellites in medium altitude orbit to provide personal communications satellite service. The Odyssey communications system projects a multibeam antenna pattern to the Earth. The attitude control system orients the satellites to ensure constant coverage of land mass and coastal areas. Pointing can be reprogrammed by ground control to ensure optimized coverage of the desired service areas. The payload architecture features non-processing, "bent pipe" transponders and matrix amplifiers to ensure dynamic power delivery to high demand areas. Circuit capacity is 3000 circuits per satellite. Each satellite weighs 1917 kg (4226 pounds) at launch and the solar arrays provide 3126 Watts of power. Satellites are launched in pairs on Ariane, Atlas, or other vehicles. Each satellite is placed in a circular orbit at an altitude of 10,354 km. There are three orbit planes inclined at 55° to the equatorial plane

  18. Combined air and water pollution control system

    Science.gov (United States)

    Wolverton, Billy C. (Inventor); Jarrell, Lamont (Inventor)

    1990-01-01

    A bioaquatic air pollution control system for controlling both water and atmospheric pollution is disclosed. The pollution control system includes an exhaust for directing polluted gases out of a furnace and a fluid circulating system which circulates fluid, such as waste water, from a source, past the furnace where the fluid flow entrains the pollutants from the furnace. The combined fluid and pollutants are then directed through a rock/plant/microbial filtering system. A suction pump pumps the treated waste water from the filter system past the exhaust to again entrain more pollutants from the furnace where they are combined with the fluid (waste water) and directed to the filter system.

  19. Communications article

    KAUST Repository

    Fariborzi, Hossein

    2017-07-20

    Seamless, covert communications using a communications system integrated or incorporated within an article of clothing is described. In one embodiment, the communications system is integrated or incorporated into a shoe insole and includes a haptic feedback mechanism, a communications module, a flexible pressure sensor, and a battery. The communications module includes a wireless communications module for wireless communications, a wired interface for wired communications, a microcontroller, and a battery charge controller. The flexible pressure sensor can be actuated by an individual\\'s toe, for example, and communication between two communications nodes can be achieved using coded signals sent by individuals using a combination of long and short presses on the pressure sensor. In response to the presses, wireless communications modules can transmit and receive coded signals based on the presses.

  20. Digital Autonomous Terminal Access Communication (DATAC) system

    Science.gov (United States)

    Novacki, Stanley M., III

    1987-01-01

    In order to accommodate the increasing number of computerized subsystems aboard today's more fuel efficient aircraft, the Boeing Co. has developed the DATAC (Digital Autonomous Terminal Access Control) bus to minimize the need for point-to-point wiring to interconnect these various systems, thereby reducing total aircraft weight and maintaining an economical flight configuration. The DATAC bus is essentially a local area network providing interconnections for any of the flight management and control systems aboard the aircraft. The task of developing a Bus Monitor Unit was broken down into four subtasks: (1) providing a hardware interface between the DATAC bus and the Z8000-based microcomputer system to be used as the bus monitor; (2) establishing a communication link between the Z8000 system and a CP/M-based computer system; (3) generation of data reduction and display software to output data to the console device; and (4) development of a DATAC Terminal Simulator to facilitate testing of the hardware and software which transfer data between the DATAC's bus and the operator's console in a near real time environment. These tasks are briefly discussed.

  1. mm-Wave Communication Systems at W-Band

    Institute of Scientific and Technical Information of China (English)

    FAN Yong; WU Zheng-de; TANG Xiao-hong

    2005-01-01

    Two communication systems at W-band are introduced, including the system design, the modulation scheme, etc. TV delivery system delivers picture of quality meeting grade 4.5 over 8 km (no rain). Digital communication system is capable of operating at data rates up to 8.448 Mb/s beyond 10 km under a BER of 10-6 (clear).

  2. Method and system for pipeline communication

    Science.gov (United States)

    Richardson,; John, G [Idaho Falls, ID

    2008-01-29

    A pipeline communication system and method includes a pipeline having a surface extending along at least a portion of the length of the pipeline. A conductive bus is formed to and extends along a portion of the surface of the pipeline. The conductive bus includes a first conductive trace and a second conductive trace with the first and second conductive traces being adapted to conformally couple with a pipeline at the surface extending along at least a portion of the length of the pipeline. A transmitter for sending information along the conductive bus on the pipeline is coupled thereto and a receiver for receiving the information from the conductive bus on the pipeline is also couple to the conductive bus.

  3. Cascaded FSO-VLC Communication System

    KAUST Repository

    Gupta, Akash

    2017-08-28

    The proposed cascaded free space optics (FSO)-visible light communication (VLC) system consists of multiple VLC access points which caters the end users connected via a decode and forward (DF) relay to the FSO backhaul link. The FSO link is assumed to be affected by path-loss, pointing error and atmospheric turbulence while the end-to-end signal-to-noise ratio (SNR) of VLC downlinks are statistically characterized considering the randomness of users position. In this study, the novel closed form expressions of the statistics like probability density function (PDF) and cumulative distribution function (CDF) of the equivalent SNR are derived. Capitalizing on these, the closed form expressions for various performance metrics such as outage probability and error probability are provided. The simulation results are provided to verify the functional curves of mathematical analysis.

  4. Secure Communication System Basedon Chaosin Optical Fibre

    Institute of Scientific and Technical Information of China (English)

    Pak L Chu; Fan Zhang; William Mak; Robust Lai

    2003-01-01

    @@ 1 Introduction Recently, there have been intense research activities on the study of synchronized chaos generated by fibre lasers [1] and its application to secure communication systems . So far, all studies concentrate on two aspects:[2].So far,all studies concentrate on two aspects:(1) the effect of the transmission channel between the transmitter and the receiver has been neglected, and (2)the chaos and the signal are carried by one wavelength.Both theoretical and experimental investigations make these two assumptions. In the experiments, the transmission fibre is invariably short, in the order of tens of metres. Hence its dispersion and nonlinear effects are negligible. The fibre laser responsible for the generation of chaos is often designed to lase at one wavelength only.

  5. Raman amplification in optical communication systems

    DEFF Research Database (Denmark)

    Kjær, Rasmus

    2008-01-01

    Fiber Raman amplifiers are investigated with the purpose of identifying new applications and limitations for their use in optical communication systems. Three main topics are investigated, namely: New applications of dispersion compensating Raman amplifiers, the use Raman amplification to increase...... fiberbaserede Raman-forstærkere med henblik på at identificere både deres begrænsninger og nye anvendelsesmuligheder i optiske kommunikationssystemer. En numerisk forstærkermodel er blevet udviklet for bedre at forstå forstærkerens dynamik, dens gain- og støjbegrænsninger. Modellen bruges til at forudsige...... forstærkerens statiske og dynamiske egenskaber, og det eftervises at dens resultater er i god overensstemmelse med eksperimentelle forstærkermålinger. Dispersions-kompenserende fiber er på grund af sin store udbredelse og fiberens høje Raman gain effektivitet et meget velegnet Raman gain-medium. Tre nye...

  6. RCT: 2.02 Communication Systems, Course #33339

    Energy Technology Data Exchange (ETDEWEB)

    Hillmer, Kurt T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-01

    This unit will present an overview of communication systems at LANL. Good communication skills are essential to an RCT. RCTs should develop an ability to communicate, using both verbal and nonverbal media. These skills will ensure that important information is transmitted to the proper individuals in a clear and concise manner.

  7. Establishing Conventional Communication Systems: Is Common Knowledge Necessary?

    Science.gov (United States)

    Barr, Dale J.

    2004-01-01

    How do communities establish shared communication systems? The Common Knowledge view assumes that symbolic conventions develop through the accumulation of common knowledge regarding communication practices among the members of a community. In contrast with this view, it is proposed that coordinated communication emerges a by-product of local…

  8. Architecting Communication Network of Networks for Space System of Systems

    Science.gov (United States)

    Bhasin, Kul B.; Hayden, Jeffrey L.

    2008-01-01

    The National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) are planning Space System of Systems (SoS) to address the new challenges of space exploration, defense, communications, navigation, Earth observation, and science. In addition, these complex systems must provide interoperability, enhanced reliability, common interfaces, dynamic operations, and autonomy in system management. Both NASA and the DoD have chosen to meet the new demands with high data rate communication systems and space Internet technologies that bring Internet Protocols (IP), routers, servers, software, and interfaces to space networks to enable as much autonomous operation of those networks as possible. These technologies reduce the cost of operations and, with higher bandwidths, support the expected voice, video, and data needed to coordinate activities at each stage of an exploration mission. In this paper, we discuss, in a generic fashion, how the architectural approaches and processes are being developed and used for defining a hypothetical communication and navigation networks infrastructure to support lunar exploration. Examples are given of the products generated by the architecture development process.

  9. Latency Analysis of Systems with Multiple Interfaces for Ultra-Reliable M2M Communication

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Popovski, Petar

    2016-01-01

    One of the ways to satisfy the requirements of ultra-reliable low latency communication for mission critical Machine-type Communications (MTC) applications is to integrate multiple communication interfaces. In order to estimate the performance in terms of latency and reliability...... of such an integrated communication system, we propose an analysis framework that combines traditional reliability models with technology-specific latency probability distributions. In our proposed model we demonstrate how failure correlation between technologies can be taken into account. We show for the considered...

  10. Advanced Communication System in Substation for Integrated Protection

    Institute of Scientific and Technical Information of China (English)

    HE Jinghan; REN Yingli; BO Zhiqian; Klimek Adrew

    2008-01-01

    This paper proposes an advanced substation integrated protection communication sys- tem based on the latest development in power system. The integrated protection communication system within a substation comprises a number of major components such as the merging unit, communication network and integrated protection unit. The design and capability evaluation of the communication network based on IEC61850 are focused on. Results show that huge information from 4 merging units can be transmitted real-time via adopting 100 Mbit/s optical fiber in a sub-station, and the proposed communication network is able to achieve required performance.

  11. Principles of spread-spectrum communication systems

    CERN Document Server

    Torrieri, Don

    2015-01-01

    This book provides a concise but lucid explanation of the fundamentals of spread-spectrum systems with an emphasis on theoretical principles. The choice of specific topics is tempered by the author’s judgment of their practical significance and interest to both researchers and system designers. The book contains many improved derivations of the classical theory and presents the latest research results that bring the reader to the frontier of the field. This third edition includes new coverage of topics such as CDMA networks, acquisition and synchronization in DS-CDMA cellular networks, hopsets for FH-CDMA ad hoc networks, implications of information theory, the central limit theorem, the power spectral density of FH/CPM complex envelopes, adaptive filters, and adaptive arrays.   ·         Focuses on the fundamentals of spread-spectrum communication systems and provides current examples of their applications ·         Includes problem sets at the end of each chapter to assist readers in co...

  12. Technology for a quasi-GSO satellite communications system

    OpenAIRE

    Katagi, T.; Yonezawa, R.; Chiba, I.; Urasaki, S.

    1999-01-01

    In this paper, a satellite communications system using a Quasi Geostationary Satellite Orbit (Quasi-GSO) is proposed. A 24-hour period Quasi-GSO system could give high quality communication to high latitude regions with its satellites observed from earth stations having high elevation angles. In this paper, a system concept and a deployable flat antenna with light weight antenna elements are described proposing it to be a good candidate for mobile communications satellite use.

  13. The international maritime satellite communications system INMARSAT (Handbook)

    Science.gov (United States)

    Zhilin, Viktor A.

    The organization and services provided by the INMARSAT satellite communications system are summarized. The structure and operation of the system are described with reference to transmission line parameters, frequency assignment, signals, telex communications, electrical parameters of communication channels, modulation, synchronization, and methods of protection against errors in the transmission of discrete messages. The discussion also covers the principal components of the INMARSAT system and the operation of ship-based stations.

  14. Consensus of Heterogeneous Multiagent Systems with Arbitrarily Bounded Communication Delay

    Directory of Open Access Journals (Sweden)

    Xue Li

    2017-01-01

    Full Text Available This paper focuses on the consensus problem of high-order heterogeneous multiagent systems with arbitrarily bounded communication delays. Through the method of nonnegative matrices, we get a sufficient consensus condition for the systems with dynamically changing topology. The results of this paper show, even when there are arbitrarily bounded communication delays in the systems, all agents can reach a consensus no matter whether there are spanning trees for the corresponding communication graphs at any time.

  15. Wireless multimedia communication systems design, analysis, and implementation

    CERN Document Server

    Rao, KR; Bakmaz, Bojan M

    2014-01-01

    Rapid progress in software, hardware, mobile networks, and the potential of interactive media poses many questions for researchers, manufacturers, and operators of wireless multimedia communication systems. Wireless Multimedia Communication Systems: Design, Analysis, and Implementation strives to answer those questions by not only covering the underlying concepts involved in the design, analysis, and implementation of wireless multimedia communication systems, but also by tackling advanced topics such as mobility management, security components, and smart grids.Offering an accessible treatment

  16. Why language really is not a communication system: a cognitive view of language evolution.

    Science.gov (United States)

    Reboul, Anne C

    2015-01-01

    While most evolutionary scenarios for language see it as a communication system with consequences on the language-ready brain, there are major difficulties for such a view. First, language has a core combination of features-semanticity, discrete infinity, and decoupling-that makes it unique among communication systems and that raise deep problems for the view that it evolved for communication. Second, extant models of communication systems-the code model of communication (Millikan, 2005) and the ostensive model of communication (Scott-Phillips, 2015) cannot account for language evolution. I propose an alternative view, according to which language first evolved as a cognitive tool, following Fodor's (1975, 2008) Language of Thought Hypothesis, and was then exapted (externalized) for communication. On this view, a language-ready brain is a brain profoundly reorganized in terms of connectivity, allowing the human conceptual system to emerge, triggering the emergence of syntax. Language as used in communication inherited its core combination of features from the Language of Thought.

  17. The Guided System Development Framework: Modeling and Verifying Communication Systems

    DEFF Research Database (Denmark)

    Carvalho Quaresma, Jose Nuno; Probst, Christian W.; Nielson, Flemming

    2014-01-01

    In a world that increasingly relies on the Internet to function, application developers rely on the implementations of protocols to guarantee the security of data transferred. Whether a chosen protocol gives the required guarantees, and whether the implementation does the same, is usually unclear....... The Guided System Development framework contributes to more secure communication systems by aiding the development of such systems. The framework features a simple modelling language, step-wise refinement from models to implementation, interfaces to security verification tools, and code generation from...

  18. A Molecular Communication System Model for Particulate Drug Delivery Systems.

    Science.gov (United States)

    Chahibi, Youssef; Pierobon, Massimiliano; Song, Sang Ok; Akyildiz, Ian F

    2013-12-01

    The goal of a drug delivery system (DDS) is to convey a drug where the medication is needed, while, at the same time, preventing the drug from affecting other healthy parts of the body. Drugs composed of micro- or nano-sized particles (particulate DDS) that are able to cross barriers which prevent large particles from escaping the bloodstream are used in the most advanced solutions. Molecular communication (MC) is used as an abstraction of the propagation of drug particles in the body. MC is a new paradigm in communication research where the exchange of information is achieved through the propagation of molecules. Here, the transmitter is the drug injection, the receiver is the drug delivery, and the channel is realized by the transport of drug particles, thus enabling the analysis and design of a particulate DDS using communication tools. This is achieved by modeling the MC channel as two separate contributions, namely, the cardiovascular network model and the drug propagation network. The cardiovascular network model allows to analytically compute the blood velocity profile in every location of the cardiovascular system given the flow input by the heart. The drug propagation network model allows the analytical expression of the drug delivery rate at the targeted site given the drug injection rate. Numerical results are also presented to assess the flexibility and accuracy of the developed model. The study of novel optimization techniques for a more effective and less invasive drug delivery will be aided by this model, while paving the way for novel communication techniques for Intrabody communication networks.

  19. Radiation Hard Electronics for Advanced Communication Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced reconfigurable/reprogrammable communication systems will require use of commercial sub 100 nm electronics. Legacy radiation tolerant circuits fail to...

  20. Advanced integrated WDM system for POF communication

    Science.gov (United States)

    Haupt, M.; Fischer, U. H. P.

    2009-01-01

    Polymer Optical Fibres (POFs) show clear advantages compared to copper and glass fibres. In essence, POFs are inexpensive, space-saving and not susceptible to electromagnetic interference. Thus, the usage of POFs have become a reasonable alternative in short distance data communication. Today, POFs are applied in a wide number of applications due to these specific advantages. These applications include automotive communication systems and in-house-networks. State-of-the-art is to transmit data with only one channel over POF, this limits the bandwidth. To solve this problem, an integrated MUX/DEMUX-element for WDM over POF is designed and developed to use multiple channels. This integration leads to low costs, therefore this component is suitable for mass market applications. The fundamental idea is to separate the chromatic parts of the light in its monochromatic components by means of a grating based on an aspheric mirror. Due to the high NA of the POF the setup has to be designed in a 3D-approach. Therefore this setup cannot be compared with the planar solutions available on market, they would result high losses in the 3rd dimension. To achieve a fast and optimized design an optical simulation program is used. Particular attention has to be paid to the design of the POF as a light source in the simulation program and the optimisation of the grating. The following realization of the demultiplexer is planed to be done with injection molding. This technology offers easy and very economical processing. These advantages make this technology first choice for optical components in the low-cost array.

  1. Communication and control tools, systems, and new dimensions

    CERN Document Server

    MacDougall, Robert; Cummings, Kevin

    2015-01-01

    Communication and Control: Tools, Systems, and New Dimensions advocates a systems view of human communication in a time of intelligent, learning machines. This edited collection sheds new light on things as mundane yet still profoundly consequential (and seemingly "low-tech") today as push buttons, pagers and telemarketing systems. Contributors also investigate aspects of "remote control" related to education, organizational design, artificial intelligence, cyberwarfa

  2. Tactical Communications Training Environment for Unmanned Aircraft System Operators

    Science.gov (United States)

    2016-12-15

    processing, with a human performance measurement platform to provide interactions, in a nominal mission environment, thereby enabling training of critical...voice communication skills. Real-time audio feedback was provided to Soldiers throughout communications with virtual entities. Access to remediation...UAS simulation platform , (b) a commercial speech recognition system, (c) natural language parsing system, (d) human performance measurement system

  3. Communications and control for electric power systems

    Science.gov (United States)

    Kirkham, H.

    1992-01-01

    A long-term strategy for the integration of new control technologies for power generation and delivery is proposed: the industry would benefit from an evolutionary approach that would adapt to its needs future technologies as well as those that it has so far not heeded. The integrated operation of the entire system, including the distribution system, was proposed as a future goal. The AbNET communication protocols are reviewed, and additions that were made in 1991 are described. In the original network, traffic was controlled by polling at the master station, located at the substation, and routed by a flooding algorithm. In a revised version, the polling and flooding are modified. The question of interfacing low-energy measurement transducers or instrument transformers is considered. There is presently little or no agreement on what the output of optical current transducers (CT's) should be. Appendices deal with the calibration of current transducers; with Delta modulation, a simple means of serially encoding the output of an OCT; and with noise shaping, a method of digital signal processing that trades off the number of bits in a digital sample for a higher number of samples.

  4. Rapid Polarization Activity in Optical Communication Systems

    Science.gov (United States)

    Yevick, David; Reimer, Michael; Soliman, George

    2010-03-01

    We have recently analyzed the high-speed polarization and polarization-mode-dispersion (PMD) transients associated with mechanical impacts on a dispersion compensation module consisting of several km of optical fiber. These generate in our experiments rotational frequencies of up to several hundred radians/sec on the Poincare sphere that can severely degrade the performance of both standard and non-conventional communications systems. Accordingly, we implemented several procedures for performing high-speed polarization measurements, employed these to analyze small and large amplitude excitations and compared the results with a heuristic fiber model. Theoretically, we extended our previous work on applying the Magnus expansion to the analysis of the dependence of the PMD and polarization-dependent-loss (PDL) on frequency. From these, we obtained simple procedures for modeling polarization behavior over a wide frequency range from a small number of experimental measurements. Finally, we analyzed the applicability of various models of stochastic time-dependent refractive index variations to system outage prediction.

  5. Potentials and Limitations of CDMA Networks for Combined Inter-Satellite Communication and Relative Navigation

    NARCIS (Netherlands)

    Sun, R.; Guo, J.; Gill, E.K.A.; Maessen, D.C.

    2012-01-01

    Precision formation flying missions require formation acquisition and maintenance through the interactions among spacecraft by the inter-satellite communication and relative navigation. This paper analyses the dedicated system constraints of the network architecture for precision formation flying mi

  6. Representing clinical communication knowledge through database management system integration.

    Science.gov (United States)

    Khairat, Saif; Craven, Catherine; Gong, Yang

    2012-01-01

    Clinical communication failures are considered the leading cause of medical errors [1]. The complexity of the clinical culture and the significant variance in training and education levels form a challenge to enhancing communication within the clinical team. In order to improve communication, a comprehensive understanding of the overall communication process in health care is required. In an attempt to further understand clinical communication, we conducted a thorough methodology literature review to identify strengths and limitations of previous approaches [2]. Our research proposes a new data collection method to study the clinical communication activities among Intensive Care Unit (ICU) clinical teams with a primary focus on the attending physician. In this paper, we present the first ICU communication instrument, and, we introduce the use of database management system to aid in discovering patterns and associations within our ICU communications data repository.

  7. Gas Main Sensor and Communications Network System

    Energy Technology Data Exchange (ETDEWEB)

    Hagen Schempf

    2006-05-31

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the Northeast Gas Association (NGA), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. This projected was completed in April 2006, and culminated in the installation of more than 2 dozen GasNet nodes in both low- and high-pressure cast-iron and steel mains owned by multiple utilities in the northeastern US. Utilities are currently logging data (off-line) and monitoring data in real time from single and multiple networked sensors over cellular networks and collecting data using wireless bluetooth PDA systems. The system was designed to be modular, using in-pipe sensor-wands capable of measuring, flow, pressure, temperature, water-content and vibration. Internal antennae allowed for the use of the pipe-internals as a waveguide for setting up a sensor network to collect data from multiple nodes simultaneously. Sensor nodes were designed to be installed with low- and no-blow techniques and tools. Using a multi-drop bus technique with a custom protocol, all electronics were designed to be buriable and allow for on-board data-collection (SD-card), wireless relaying and cellular network forwarding. Installation options afforded by the design included direct-burial and external polemounted variants. Power was provided by one or more batteries, direct AC-power (Class I Div.2) and solar-array. The utilities are currently in a data-collection phase and intend to use the collected (and processed) data to make capital improvement decisions, compare it to Stoner model predictions and evaluate the use of such a system for future expansion, technology-improvement and commercialization starting later in 2006.

  8. Remote Monitoring System for Communication Base Based on Short Message

    Directory of Open Access Journals (Sweden)

    Han Yu Fu

    2013-07-01

    Full Text Available This paper presents design and development of an automatic monitoring system of communication base which is an important means to realize modernization of mobile communication base station management. Firstly, this paper proposes the architecture of the monitoring system. The proposed system consists of mocrocontrollers, sensors, GSM module and MFRC500 etc. The value of parameters is measured in the system including terminal is studied and designed, including hardware design based on embedded system and software design. Finally, communication module is discussed. The monitoring system which is designed  based on GSM SMS(short message service can improve the integrity, reliability, flexibility and intellectuality of monitoring system.

  9. Global System for Mobile Communication Based Smart Home Security System

    Directory of Open Access Journals (Sweden)

    Amrit Zoad

    2014-07-01

    Full Text Available Home security system is needed for occupants' convenience and safety. In this paper, we present the design and implementation of an affordable, low power consumption, and GSM (Global System for Mobile Communication based wireless home security system. In existing system, the home network is engaged with non-wireless technology, where the installation and maintenance is difficult. So the system cost is very high. In our proposed system, these difficulties are overcome by introducing a wireless home network which contains a GPRS Gateway and three kinds of security nodes namely door security node, anti intrusion node and SMS node to inform the user. The nodes are easy installing. All the three nodes are connected to the microcontroller.

  10. Design of pulse waveform for waveform division multiple access UWB wireless communication system.

    Science.gov (United States)

    Yin, Zhendong; Wang, Zhirui; Liu, Xiaohui; Wu, Zhilu

    2014-01-01

    A new multiple access scheme, Waveform Division Multiple Access (WDMA) based on the orthogonal wavelet function, is presented. After studying the correlation properties of different categories of single wavelet functions, the one with the best correlation property will be chosen as the foundation for combined waveform. In the communication system, each user is assigned to different combined orthogonal waveform. Demonstrated by simulation, combined waveform is more suitable than single wavelet function to be a communication medium in WDMA system. Due to the excellent orthogonality, the bit error rate (BER) of multiuser with combined waveforms is so close to that of single user in a synchronous system. That is to say, the multiple access interference (MAI) is almost eliminated. Furthermore, even in an asynchronous system without multiuser detection after matched filters, the result is still pretty ideal and satisfactory by using the third combination mode that will be mentioned in the study.

  11. 人脸识别考勤系统联合信息平台提高首台手术准时率%Application of face recognition based time attendance system combined with multiple communication systems to operating room to boost punctual start of the first surgery of the day

    Institute of Scientific and Technical Information of China (English)

    罗忠梅; 曹阳慧; 张相云; 周淑云; 雷菊红

    2012-01-01

    目的 探讨人脸识别考勤系统联合信息系统提高首台手术准时率的效果.方法 选择2012年1~4月首台手术的1 790例作为观察组,采取人脸识别考勤系统联合手术麻醉信息系统、短信提醒系统、手术信息显示系统多部门协作进行管理.选择2011年1~4月首台手术1 548例作为对照组,采取巡回护士电话催促手术医生到位、护士长登记上报的方式管理.结果 观察组首台手术准时率较对照组显著上升,因手术医生迟到造成首台手术未准时开台率显著下降(均P<0.01).结论 加强首台手术准时开始工作的管理非常必要,人脸识别考勤系统及各信息平台优势明显,提高了首台手术的准时率.%Objective To explore whether the application of face recognition based time attendance system combined with multiple communication systems improve punctual start of the first surgery of the day. Methods A total of 1790 cases receiving their surgery as the first one of the day from January to April of 2012 were assigned into an observation group, for which a face recognition based time attendance system combined with surgical anesthesia system, text messaging system, operation information display system were applied and multi-sector collaboration was achieved. Totally , 1548 cases as counterparts from January to April in 2011 were taken as the control group, for which, circulating nurses made phone calls to push surgeons to be on time for the first surgery. For surgeons who failed to arrive on time, the head nurses wrote down their names and frequency of delays and reported to supervising departments. Results The rate of on-time start of the first operation in the observation group was significantly higher than that in the control group, rate of delayed start of the first surgery due to surgeons being late dropped significantly (P<0. 01 for both). Conclusion It is very necessary to reinforce on-time start of the first operation of the day

  12. Fractional Chaos Based Communication Systems-An Introduction

    Institute of Scientific and Technical Information of China (English)

    Juebang Yu

    2008-01-01

    As one of secure communication means, chaotic communication systems has been well-developed during the past three decades. Technical papers, both for theoretical and practical investigations, have reached a huge amount in number. On the other hand, fractional chaos, as a parallel ongoing research topic, also attracts many researchers to investigate. As far as the IT field is concerned, the research on control systems by using fractional chaos known as FOC (fractional order control) has been a hot issue for quite a long time. As a comparison, interesting enough, up to now we have not found any research result related to Fractional Chaos Communi cation (FCC) system, Le., a system based on fractional chaos. The motivation of the present article is to reveal the feasibility of realizing communication systems based upon FCC and their superiority over the conventional integer chaotic communication systems. Principles of FCC and its advantages over integer chaotic communication systems are also discussed.

  13. An ATP System for Deep-Space Optical Communication

    Science.gov (United States)

    Lee, Shinhak; Irtuzm Gerardi; Alexander, James

    2008-01-01

    An acquisition, tracking, and pointing (ATP) system is proposed for aiming an optical-communications downlink laser beam from deep space. In providing for a direction reference, the concept exploits the mature technology of star trackers to eliminate the need for a costly and potentially hazardous laser beacon. The system would include one optical and two inertial sensors, each contributing primarily to a different portion of the frequency spectrum of the pointing signal: a star tracker (50 Hz. The outputs of these sensors would be combined in an iterative averaging process to obtain high-bandwidth, high-accuracy pointing knowledge. The accuracy of pointing knowledge obtainable by use of the system was estimated on the basis of an 8-cm-diameter telescope and known parameters of commercially available star trackers and inertial sensors: The single-axis pointing-knowledge error was found to be characterized by a standard deviation of 150 nanoradians - below the maximum value (between 200 and 300 nanoradians) likely to be tolerable in deep-space optical communications.

  14. Full-duplex wireless communications systems self-interference cancellation

    CERN Document Server

    Le-Ngoc, Tho

    2017-01-01

    This book introduces the development of self-interference (SI)-cancellation techniques for full-duplex wireless communication systems. The authors rely on estimation theory and signal processing to develop SI-cancellation algorithms by generating an estimate of the received SI and subtracting it from the received signal. The authors also cover two new SI-cancellation methods using the new concept of active signal injection (ASI) for full-duplex MIMO-OFDM systems. The ASI approach adds an appropriate cancelling signal to each transmitted signal such that the combined signals from transmit antennas attenuate the SI at the receive antennas. The authors illustrate that the SI-pre-cancelling signal does not affect the data-bearing signal. This book is for researchers and professionals working in wireless communications and engineers willing to understand the challenges of deploying full-duplex and practical solutions to implement a full-duplex system. Advanced-level students in electrical engineering and computer ...

  15. Analysis of Maritime Mobile Satellite Communication Systems

    Science.gov (United States)

    1988-12-01

    Communications and Surveil- lance, IEE, Conference publication n.95, 13-15 Mar. 1973. 2. Y. Karasawa and T. Shiokawa , Characteristics of L-Band Multipath Fading... Shiokawa . Analysis of M-ultipath Fading due to Sea Suface Scattering in Maritime Satellite Communication, Technical Group on Antennas and Propagation. IECE

  16. Communication Systems for Grid Integration of Renewable Energy Resources

    CERN Document Server

    Yu, F Richard; Xiao, Weidong; Choudhury, Paul

    2011-01-01

    There is growing interest in renewable energy around the world. Since most renewable sources are intermittent in nature, it is a challenging task to integrate renewable energy resources into the power grid infrastructure. In this grid integration, communication systems are crucial technologies, which enable the accommodation of distributed renewable energy generation and play extremely important role in monitoring, operating, and protecting both renewable energy generators and power systems. In this paper, we review some communication technologies available for grid integration of renewable energy resources. Then, we present the communication systems used in a real renewable energy project, Bear Mountain Wind Farm (BMW) in British Columbia, Canada. In addition, we present the communication systems used in Photovoltaic Power Systems (PPS). Finally, we outline some research challenges and possible solutions about the communication systems for grid integration of renewable energy resources.

  17. Integrated Train Ground Radio Communication System Based TD-LTE

    Institute of Scientific and Technical Information of China (English)

    ZHAO Hongli; CAO Yuan; ZHU Li; XU Wei

    2016-01-01

    In existing metro systems, the train ground radio communication system for different applications are deployed independently. Investing and constructing the communication infrastructures repeatedly wastes substan-tial social resources, and it brings difficulties to maintain all these infrastructures. We present the communication Quality of service (QoS) requirement for different train ground radio applications. An integrated TD-LTE based train ground radio communication system for the metro system (LTE-M) is designed next. In order to test the LTE-M system performance, an indoor testing environment is set up. The channel simulator and programmable attenua-tors are used to simulate the real metro environment. Ex-tensive test results show that the designed LTE-M system performance satisfies metro communication requirements.

  18. [The CORBA solution of medical imaging and communication system].

    Science.gov (United States)

    Wang, Yong; Lü, Yangsheng; Yu, Hui

    2005-02-01

    Due to the difficulty of communication and information share between Medical information systems, the Object Management Group issued the software specification of CORBAMed, defining the interfaces of services, and specifying the software architecture of Medical Information System. This paper attempts to use CORBA in Picture Archiving and Communication System (PACS), provides a system model of CORBA solution of PACS, and analyzes the view layers structure of system, finally we discuss the related services of CORBAMed.

  19. A Positioning System based on Communication Satellites and the Chinese Area Positioning System (CAPS)

    Science.gov (United States)

    Ai, Guo-Xiang; Shi, Hu-Li; Wu, Hai-Tao; Yan, Yi-Hua; Bian, Yu-Jing; Hu, Yong-Hui; Li, Zhi-Gang; Guo, Ji; Xian-DeCai

    2008-12-01

    The Chinese Area Positioning System (CAPS) is a positioning system based on satellite communication that is fundamentally different from the 3``G'' (GPS, GLONASS and GALILEO) systems. The latter use special-purpose navigation satellites to broadcast navigation information generated on-board to users, while the CAPS transfers ground-generated navigation information to users via the communication satellite. In order to achieve accurate Positioning, Velocity and Time (PVT), the CAPS employs the following strategies to overcome the three main obstacles caused by using the communication satellite: (a) by real-time following-up frequency stabilization to achieve stable frequency; (b) by using a single carrier in the transponder with 36 MHz band-width to gain sufficient power; (c) by incorporating Decommissioned Geostationary Orbit communication satellite (DGEO), barometric pressure and Inclined Geostationary Orbit communication satellite (IGSO) to achieve the 3-D positioning. Furthermore, the abundant transponders available on DGEO can be used to realize the large capacity of communication as well as the integrated navigation and communication. With the communication functions incorporated, five new functions appear in the CAPS: (1) combination of navigation and communication; (2) combination of navigation and high accuracy orbit measurement; (3) combination of navigation message and wide/local area differential processing; (4) combination of the switching of satellites, frequencies and codes; and (5) combination of the navigation message and the barometric altimetry. The CAPS is thereby labelled a PVT5C system of high accuracy. In order to validate the working principle and the performance of the CAPS, a trial system was established in the course of two years at a cost of about 20 million dollars. The trial constellation consists of two GEO satellites located at E87.5° and E110.5°, two DGEOs located at E130° and E142°, as well as barometric altimetry as a virtual

  20. A Positioning System based on Communication Satellites and the Chinese Area Positioning System (CAPS)

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The Chinese Area Positioning System (CAPS) is a positioning system based on satellite communication that is fundamentally different from the 3"G" (GPS, GLONASS and GALILEO) systems. The latter use special-purpose navigation satellites to broadcast navi-gation information generated on-board to users, while the CAPS transfers ground-generated navigation information to users via the communication satellite. In order to achieve accurate Positioning, Velocity and Time (PVT), the CAPS employs the following strategies to over-come the three main obstacles caused by using the communication satellite: (a) by real-time following-up frequency stabilization to achieve stable frequency; (b) by using a single carrier in the transponder with 36 MHz band-width to gain sufficient power; (c) by incorporating Decommissioned Geostationary Orbit communication satellite (DGEO), barometric pressure and Inclined Geostationary Orbit communication satellite (IGSO) to achieve the 3-D posi-tioning. Furthermore, the abundant transponders available on DGEO can be used to realize the large capacity of communication as well as the integrated navigation and communication. With the communication functions incorporated, five new functions appear in the CAPS: (1) combination of navigation and communication; (2) combination of navigation and high accu-racy orbit measurement; (3) combination of navigation message and wide/local area differen-tial processing; (4) combination of the switching of satellites, frequencies and codes; and (5) combination of the navigation message and the barometric altimetry. The CAPS is thereby labelled a PVT5C system of high accuracy. In order to validate the working principle and the performance of the CAPS, a trial system was established in the course of two years at a cost of about 20 million dollars. The trial constellation consists of two GEO satellites located at E87.5°and E110.5°, two DGEOs located at E130° and E142°, as well as barometric altimetry as a virtual

  1. Technology Evaluation of Programmable Communicating Thermostats with Radio Broadcast Data System Communications

    Energy Technology Data Exchange (ETDEWEB)

    Herter, Karen; Wayland, Seth

    2008-10-31

    Programmable Communicating Thermostats are thermostats that can be programmed by the user to respond to signals indicating a grid-level system emergency or pricing event. The California Energy Commission is considering standards that would include a requirement for Programmable Communicating Thermostats in residential and small commercial applications. The current specification for Programmable Communicating Thermostats requires Radio Data System communications to Programmable Communicating Thermostats. This study tested the signal strength and reliability of Radio Data System signals at 40 customer sites within the Sacramento Municipal Utility District, which is serviced by 17 radio stations that already transmit Radio Data System signals. The study also tested the functionality of a commercially available Programmable Communicating Thermostat for compliance with California Energy Commission design standards. Test results demonstrated that Radio Data System is capable of reliably sending price and emergency signals. This study also provides evidence that existing Programmable Communicating Thermostats, on receiving a Radio Data System pricing or event signal, are capable of automatically increasing set points to a customer-determined or utility-determined level, thus providing air-conditioning demand response within seconds or just a few (less than 5) minutes.

  2. Design and Implementation of a Modular Biomimetic Infochemical Communication System

    NARCIS (Netherlands)

    Rácz, Z.; Cole, M.; Gardner, J.W.; Chowdhury, M.F.; Bula, W.P.; Gardeniers, J.G.E.; Karout, S.; Capurro, A.; Pearce, T.C.

    2013-01-01

    We describe here the design and implementation of a novel biomimetic infochemical communication system that employs airborne molecules alone to communicate over space and time. The system involves the design and fabrication of a microsystem capable of producing and releasing a precise mix of biosynt

  3. HF Detecting Radar and Communication Frequency Selection System

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Real time communication (RTC) frequency selecting system is used to the maximum usable frequency (MUF) between two communication points, then finds the best frequency between 0. 85 MUF and 1.0MUF. Determination of electric wave delay is mostly introduced, and of MUF values, the form of frequencycontrolling code and relative interface circuits in the frequency selecting system are introduced in detail.

  4. INFORMATION CHARACTERIZATION OF COMMUNICATION CHANNELS FOR SYSTEM IDENTIFICATION

    Institute of Scientific and Technical Information of China (English)

    Le Yi WANG; G. George YIN

    2007-01-01

    This paper studies identification of systems in which the system output is quantized,transmitted through a digital communication channel, and observed afterwards. The concept of the CR Ratio is introduced to characterize impact of communication channels on identification. The relationship between the CR Ratio and Shannon channel capacity is discussed. Identification algorithms are further developed when the channel error probability is unknown.

  5. Channel Equalization for Chaos-Based Communication Systems

    Institute of Scientific and Technical Information of China (English)

    冯久超; 鲁瑞华

    2002-01-01

    We study the equalization of the channel for chaotic communication systems. A channel equalizer is designed and realized by a modified recurrent neural network for eliminating channel distortions. The results from computer simulations demonstrate the effectiveness of the equalizer as applied to a chaotic communication system.

  6. Design and Implementation of a Modular Biomimetic Infochemical Communication System

    NARCIS (Netherlands)

    Rácz, Z.; Cole, M.; Gardner, J.W.; Chowdhury, M.F.; Bula, W.P.; Gardeniers, Johannes G.E.; Karout, S.; Capurro, A.; Pearce, T.C.

    2013-01-01

    We describe here the design and implementation of a novel biomimetic infochemical communication system that employs airborne molecules alone to communicate over space and time. The system involves the design and fabrication of a microsystem capable of producing and releasing a precise mix of

  7. Scheduling with Optimized Communication for Time-Triggered Embedded Systems

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    1999-01-01

    We present an approach to process scheduling for synthesis of safety-critical distributed embedded systems.Our system model captures both the flow of data and that of control. The communication model is based on a time-triggered protocol. We take into consideration overheads due to communication...

  8. A Study on the M-ary/SS Communication System Using a Frame Synchronization Method of PCM Communication Systems

    OpenAIRE

    長谷川, 孝明; 羽渕, 裕真

    1994-01-01

    Copyright notice. c1994 IEICE All rights reserved. "A Study on the M-ary/SS Communication System Using a Frame Synchronization Method of PCM Communication Systems"Kouji OHUCHI, Hiromasa HABUCHI, Takaaki HASEGAWA, IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences, 1994 Vol.77-A No.11 pp. 1942-1945 許諾No.07RB0055.

  9. Reconfigurable/Reprogrammable Communication Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The future of reconfigurable/reprogrammable transceivers with !Y 1 Gbps transmission and reception data rates for future NASA space communications applications will...

  10. OFDM concepts for future communication systems

    CERN Document Server

    Rohling, Hermann

    2011-01-01

    The Orthogonal Frequency Division Multiplexing (OFDM) digital transmission technique has advantages in broadcast and mobile communications applications. This book gives a good insight into these, and provides an overview of the scientific progress.

  11. Molecular communications and nanonetworks from nature to practical systems

    CERN Document Server

    Atakan, Barış

    2014-01-01

    In this book, the concepts of molecular communications and nanonetworks are introduced. Throughout the book, the existing molecular communication paradigms are categorized into two main groups. The first group includes the Passive Molecular Communication (PMC) paradigms in which molecules freely diffuse to transfer information from a transmitter to a receiver. The second group includes the Active Molecular Communication (AMC) paradigms in which molecules are carried or guided by some mediators such as molecular motors, gap junction channels and bacteria. In the book, after briefly discussing why molecular communication is needed for the sophisticated nano and biotechnology applications, the existing molecular communication systems are first presented. Then, the principles of diffusion phenomena and molecular reception with absorbers and the ligand-receptor binding mechanism are introduced. Based on these principles, the communication theories and techniques are given for the PMC. Then, the physical dynamics o...

  12. Theoretical and experimental research on diversity reception technology in NLOS UV communication system.

    Science.gov (United States)

    Han, Dahai; Liu, Yile; Zhang, Kai; Luo, Pengfei; Zhang, Min

    2012-07-02

    Diversity reception technology is introduced into ultraviolet communication area in this article with theory analysis and practical experiment. The idea of diversity reception was known as a critical effective method in wireless communication area that improves the Gain significantly especially for the multi-scattering channel. A theoretical modeling and simulation method are proposed to depict the principle and feasibility of diversity reception adopted in UV communication. Besides, an experimental test-bed using ultraviolet LED and dual receiver of photomultiplier tube is setup to characterize the effects of diversity receiving in non-line-of-sight (NLOS) ultraviolet communication system. The experiment results are compared with the theoretical ones to verify the accuracy of theoretical modeling and the effect of diversity reception. Equal gain combining (EGC) method was adopted as the diversity mechanism in this paper. The research results of theory and experiment provide insight into the channel characteristics and achievable capabilities of ultraviolet communication system with diversity receiving method.

  13. Attacks to Cryptography Protocols of Wireless Industrial Communication Systems

    Directory of Open Access Journals (Sweden)

    Maria Franekova

    2010-01-01

    Full Text Available The paper deals with problems of safety and security principles within wireless industrial communication systems. First safety requirements to wireless industrial communication system, summarisation of attack methods and the available measures for risks elimination are described with orientation to safety critical applications. The mainly part is oriented to identification of risks and summarisation of defensive methods of wireless communication based on cryptographic techniques. Practical part the cryptoanalytic’s attacks to COTS (Commercial Off-The-Shelf wireless communications are mentioned based on the IEEE 802.11 standards.

  14. Communication satellite system beyond the year 2000

    Science.gov (United States)

    Robertson, G. J.; Fourquet, J. M.

    1991-10-01

    The primary evolutionary factors of satellite communications technologies are reviewed based on the results of a study of novel satellite developments. A critical evaluation of the viability and availability of the technologies is utilized in conjunction with market forecasts to determine promising commercial strategies. Modern technologies are almost prepared for the development of a class of communications satellites and include bandwidth utilization, spacecraft bus modularity, and functional integration.

  15. [An integrated system of blood pressure measurement with bluetooth communication].

    Science.gov (United States)

    Wang, Wei; Wang, Jing; Sun, Hongyang; Xu, Zuyang; Chai, Xinyu

    2012-07-01

    The development of the integrated blood pressure system with bluetooth communication function is introduced. Experimental results show that the system can complete blood pressure measurement and data transmission wireless effectively, which can be used in m-Health in future.

  16. Spread spectrum communication system with chaotic frequency modulation

    Science.gov (United States)

    Volkovskii, A. R.; Tsimring, L. Sh.; Rulkov, N. F.; Langmore, I.

    2005-09-01

    A new spread spectrum communication system utilizing chaotic frequency modulation of sinusoidal signals is discussed. A single phase lock loop (PLL) system in the receiver is used both to synchronize the local chaotic oscillator and to recover the information signal. We study the dynamics of the synchronization process, stability of the PLL system, and evaluate the bit-error-rate performance of this chaos-based communication system.

  17. The ELLIPSO (tm) system: Elliptical low orbits for mobile communications and other optimum system elements

    Science.gov (United States)

    Castiel, David

    1991-09-01

    On 5 Nov. 1990, Ellipsat filed with the FCC the first application to provide voice communication services via low earth orbiting (LEO) satellites. The proposed system, ELLIPSO, aims at achieving end-user costs comparable to those in the cellular industry. On 3 Jun. 1991 Ellipsat filed for the second complement of its system. Ellipsat was also the first company to propose combined position determination and mobile voice services via low-earth orbiting satellites. Ellipsat is still the only proponent of elliptical orbits for any commercial system in the United States. ELLIPSO uses a spectrum efficient combination of FDMA and CDMA techniques. Ellipsat's strategy is to tailor required capacity to user demand, reduce initial system costs and investment risks, and allow the provision of services at affordable end-user prices. ELLIPSO offers optimum features in all the components of its system, elliptical orbits, small satellites, integrated protocol and signalling system, integrated end-user electronics, novel marketing approach based on the cooperation with the tenets of mobile communications, end-user costs that are affordable, and a low risk approach as deployment is tailored to the growth of its customer base. The efficient design of the ELLIPSO constellation and system allows estimated end-user costs in the $.50 per minute range, five to six times less than any other system of comparable capability.

  18. The ELLIPSO (tm) system: Elliptical low orbits for mobile communications and other optimum system elements

    Science.gov (United States)

    Castiel, David

    1991-01-01

    On 5 Nov. 1990, Ellipsat filed with the FCC the first application to provide voice communication services via low earth orbiting (LEO) satellites. The proposed system, ELLIPSO, aims at achieving end-user costs comparable to those in the cellular industry. On 3 Jun. 1991 Ellipsat filed for the second complement of its system. Ellipsat was also the first company to propose combined position determination and mobile voice services via low-earth orbiting satellites. Ellipsat is still the only proponent of elliptical orbits for any commercial system in the United States. ELLIPSO uses a spectrum efficient combination of FDMA and CDMA techniques. Ellipsat's strategy is to tailor required capacity to user demand, reduce initial system costs and investment risks, and allow the provision of services at affordable end-user prices. ELLIPSO offers optimum features in all the components of its system, elliptical orbits, small satellites, integrated protocol and signalling system, integrated end-user electronics, novel marketing approach based on the cooperation with the tenets of mobile communications, end-user costs that are affordable, and a low risk approach as deployment is tailored to the growth of its customer base. The efficient design of the ELLIPSO constellation and system allows estimated end-user costs in the $.50 per minute range, five to six times less than any other system of comparable capability.

  19. Combined solar collector and energy storage system

    Science.gov (United States)

    Jensen, R. N. (Inventor)

    1980-01-01

    A combined solar energy collector, fluid chiller and energy storage system is disclosed. A movable interior insulated panel in a storage tank is positionable flush against the storage tank wall to insulate the tank for energy storage. The movable interior insulated panel is alternately positionable to form a solar collector or fluid chiller through which the fluid flows by natural circulation.

  20. Communications for Coordinative Control of Wind Power Systems

    DEFF Research Database (Denmark)

    Wei, Mu

    . The performances of FSWT and DFIG connected DGS are compared and analysed. At last, the cyber security study is presented, due to the important place of security in power system communications. A security domain model is proposed to guide the implementation of the security technologies. Cyber security related...... system control strategies for wind power integration, in order to achieve coordinative control for a secure and efficient power system. The project basically contains three main aspects: studies on DGS (Distributed Generation System) characteristics, analysis of communication technologies...... simulation results reveal the important impact of the security configuration on improving the performance of the associated electric power system data communication systems. This PhD study explores a new aspect of the investigations of wind power system components characteristics, from communication...

  1. Deployable Propulsion, Power and Communication Systems for Solar System Exploration

    Science.gov (United States)

    Johnson, Les; Carr, John A.; Boyd, Darren

    2017-01-01

    NASA is developing thin-film based, deployable propulsion, power, and communication systems for small spacecraft that could provide a revolutionary new capability allowing small spacecraft exploration of the solar system. By leveraging recent advancements in thin films, photovoltaics, and miniaturized electronics, new mission-level capabilities will be enabled aboard lower-cost small spacecraft instead of their more expensive, traditional counterparts, enabling a new generation of frequent, inexpensive deep space missions. Specifically, thin-film technologies are allowing the development and use of solar sails for propulsion, small, lightweight photovoltaics for power, and omnidirectional antennas for communication. Like their name implies, solar sails 'sail' by reflecting sunlight from a large, lightweight reflective material that resembles the sails of 17th and 18th century ships and modern sloops. Instead of wind, the sail and the ship derive their thrust by reflecting solar photons. Solar sail technology has been discussed in the literature for quite some time, but it is only since 2010 that sails have been proven to work in space. Thin-film photovoltaics are revolutionizing the terrestrial power generation market and have been found to be suitable for medium-term use in the space environment. When mounted on the thin-film substrate, these photovoltaics can be packaged into very small volumes and used to generate significant power for small spacecraft. Finally, embedded antennas are being developed that can be adhered to thin-film substrates to provide lightweight, omnidirectional UHF and X-band coverage, increasing bandwidth or effective communication ranges for small spacecraft. Taken together, they may enable a host of new deep space destinations to be reached by a generation of spacecraft smaller and more capable than ever before.

  2. Upgrading microwave telemetry data communications with an analog lightwave system

    Science.gov (United States)

    Reynolds, Harrell D., Jr.

    The work performed in replacing four microwave telemetry data communications systems with one single analog fiber-optics system at Edwards Air Force Base is described. The fiber-optic system used was initially designed for use in a television video system, and thus a method of aligning the fiber-optic system to meet the needs of the transmission system was required. The objectives were met by utilizing several well-known methods of AM and FM measurement techniques not yet described in the implementation of fiber-optic communications systems. After alignment, the system transmitted the already developed basebands as well as the original microwave equipment.

  3. Wireless communication for hearing aid system

    DEFF Research Database (Denmark)

    Nour, Baqer

    This thesis focuses on the wireless coupling between hearing aids close to a human head. Hearing aids constitute devices withadvanced technology and the wireless communication enables the introduction of a range of completely new functionalities. Such devices are small and the available power...... the ear-to-ear wireless communication channel by understanding the mechanisms that control the propagations of the signals and the losses. The second objective isto investigate the properties of magneto-dielectric materials and their potential in antenna miniaturization. There are three approaches...... understanding of the ear-to-ear wireless communication channel. A circular patch antenna was used to study the properties of the magneto-dielectric materials. In the thesis, we focused on three properties; efficiency, quality factor and bandwidth of the antenna. An analytical method is used to calculatethe...

  4. Communications systems and methods for subsea processors

    Science.gov (United States)

    Gutierrez, Jose; Pereira, Luis

    2016-04-26

    A subsea processor may be located near the seabed of a drilling site and used to coordinate operations of underwater drilling components. The subsea processor may be enclosed in a single interchangeable unit that fits a receptor on an underwater drilling component, such as a blow-out preventer (BOP). The subsea processor may issue commands to control the BOP and receive measurements from sensors located throughout the BOP. A shared communications bus may interconnect the subsea processor and underwater components and the subsea processor and a surface or onshore network. The shared communications bus may be operated according to a time division multiple access (TDMA) scheme.

  5. Multi-point cooperative communication systems theory and applications

    CERN Document Server

    Ding, Ming

    2013-01-01

    Multi-point Cooperative Communication Systems: Theory and Applications mainly discusses multi-point cooperative communication technologies which are used to overcome the long-standing problem of limited transmission rate caused by the inter-point interference. Instead of combating the interference, recent progress in both academia and industrial standardizations has evolved to adopt the philosophy of “exploiting” the interference to improve the transmission rate by cooperating among multiple points. This book addresses the multi-point cooperative communication system systematically giving  the readers a clear picture of the technology map and where the discussed schemes may fit. This book includes not only the theories of the paradigm-shifting multi-point cooperative communication, but also the designs of sub-optimal cooperative communication schemes for practical systems. Ming Ding is a senior researcher at Sharp Laboratories of China; Hanwen Luo is a professor at Shanghai Jiao Tong University.

  6. 622 Mbps High-speed satellite communication system for WINDS

    Science.gov (United States)

    Ogawa, Yasuo; Hashimoto, Yukio; Yoshimura, Naoko; Suzuki, Ryutaro; Gedney, Richard T.; Dollard, Mike

    2006-07-01

    WINDS is the experimental communications satellite currently under joint development by Japanese Aerospace Exploration Agency (JAXA) and the National Institute of Information and Communications Technology (NICT). The high-speed satellite communication system is very effective for quick deployment of high-speed networks economically. The WINDS will realize ultra high-speed networking and demonstrate operability of satellite communication systems in high-speed internet. NICT is now developing high-speed satellite communication system for WINDS. High-speed TDMA burst modem with high performance TPC error correction is underdevelopment. Up to the DAC on the transmitter and from the ADC on the receiver, all modem functions are performed in the digital processing technology. Burst modem has been designed for a user data rate up to 1244 Mbps. NICT is developing the digital terminal as a user interface and a network controller for this earth station. High compatibility with the Internet will be provided.

  7. Light communication systems. Citations from the NTIS data base

    Science.gov (United States)

    Reed, W. E.

    1980-09-01

    The design, performance, and application of laser, infrared, and visual communication systems are covered in the cited research reports. Transmission and equipment studies for space, atmospheric, and underwater light communication are presented. Topics covered include lasers, fiber optics, signal processing, transmission links, and data transmission. This updated bibliography contains 87 citations, 59 of which are new entries to the previous edition.

  8. Towards the next generation of nanosatellite communication systems

    NARCIS (Netherlands)

    De Milliano, M.J.; Verhoeven, C.J.M.

    2008-01-01

    The communication systems currently used on nanosatellites are usually well-proven commercial-off-the-shelf units with data rates up to 9.6 kbps. A careful analysis shows that by using advancements in microelectronics, a higher communication performance can be achieved, even within the power and mas

  9. The Use of Multiple Communication in Systemic Couples Therapy.

    Science.gov (United States)

    Keeney, Bradford P.; Siegel, Stanley

    1986-01-01

    Presents a clinical technique for working with troubled couples based on a particular theory of multiple communication in therapy. The technique, a "systemic couples reversal," prescribes a way of managing the multiple communications of stability, change, and meaningful Rorschach. Provides a theoretical map, clinical procedure, and clinical case…

  10. Measuring long-term location privacy in vehicular communication systems

    NARCIS (Netherlands)

    Ma, Zhendong; Kargl, Frank; Weber, Michael

    2010-01-01

    Vehicular communication systems are an emerging form of communication that enables new ways of cooperation among vehicles, traffic operators, and service providers. However, many vehicular applications rely on continuous and detailed location information of the vehicles, which has the potential to i

  11. Secure electronic commerce communication system based on CA

    Science.gov (United States)

    Chen, Deyun; Zhang, Junfeng; Pei, Shujun

    2001-07-01

    In this paper, we introduce the situation of electronic commercial security, then we analyze the working process and security for SSL protocol. At last, we propose a secure electronic commerce communication system based on CA. The system provide secure services such as encryption, integer, peer authentication and non-repudiation for application layer communication software of browser clients' and web server. The system can implement automatic allocation and united management of key through setting up the CA in the network.

  12. Optimization of Communication for Commanding and Controlling Systems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper mainly discussed some special requiremen ts for communication system and specific implement methods during the cause of cam paign cooperation in modern times. That system is the Advanced Field Tactical Da ta System which was developed to meet the requirements for controlling every fir e nodes, through which Army can achieve their campaign and tactical goals. The c ourse of dealing with communication message mainly include Emery's situation rep orted, Message change (generally referred to taxis a...

  13. Traffic Engineering of Cellular Wireless Communication Systems

    DEFF Research Database (Denmark)

    Iversen, Villy Bæk

    2002-01-01

    In mobile communications an efficient utilisation of the channels is of great importance. In this paper we describe the basic principles for obtaining the maximum utilisation and study strategies for obtaining these limits. In general a high degree of sharing is efficient, but requires service...

  14. Traffic Engineering of Cellular Wireless Communication Systems

    DEFF Research Database (Denmark)

    Iversen, Villy Bæk

    2002-01-01

    In mobile communications an efficient utilisation of the channels is of great importance. In this paper we describe the basic principles for obtaining the maximum utilisation and study strategies for obtaining these limits. In general a high degree of sharing is efficient, but requires service...

  15. Time-Reversal for UWB Communications Systems

    Science.gov (United States)

    2005-08-15

    Qiu, A. F. Molisch , “Ultra-wideband Wireless Communications,” Editorial on Special Issue on UWB, IEEE J. Select. Areas Com- mun.,Vol. 24, 2nd Quarter...Optical Fibers,” J. Optical Soc. of Am. Part A, Vol.11, No.12, Dec. 1994. 152. A. Molisch , “Status of Models for UWB Propagation Channel,” IEEE

  16. Henon CSK Secure Communication System Using Chaotic Turbo Codes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper,the authors design a novel chaotic secure communication system, which has high security and good errorcorrecting capability. Firstly, the Henon Chaos Shift Keying (CSK) modulation block is presented. Secondly,chaotic turbo encod er/decoder (hard decision) is introduced. Thirdly, this chaotic secure communication system, which comprises the Henon CSK modulation block and chaotic turbo en coder in a serially concatenated form, is shown. Furthermore, a novel two step encryption scheme is proposed, which is based on the chaotic turbo e ncoded Henon CSK secure communication system.

  17. Communication-based positioning systems: past, present and prospects

    Institute of Scientific and Technical Information of China (English)

    Guan-Yi Ma; Qing-Tao Wan; Tong Gan

    2012-01-01

    This paper reviews positioning systems in the context of communication systems.First,the basic positioning technique is described for location based service (LBS) in mobile communication systems.Then the high integrity global positioning system (iGPS) is introduced in terms of aspects of what it is and how the low Earth orbit (LEO) Iridium telecommunication satellites enhance the global positioning system (GPS).Emphasis is on the Chinese Area Positioning System (CAPS) which is mainly based on commercial geostationary (GEO) communication satellites,including decommissioned GEO and inclined geosynchronous communication satellites.Characterized by its low cost,high flexibility,wide-area coverage and ample frequency resources,a distinctive feature of CAPS is that its navigation messages are generated on the ground,then uploaded to and forwarded by the communication satellites.Fundamental principles and key technologies applied in the construction of CAPS are presented in detail from the CAPS validation phase to its experimental system setup.A prospective view of CAPS has concluded it to be a seamless,high accuracy,large capacity navigation and communication system which can be achieved by expanding it world wide and enhancing it with LEO satellites and mobile base stations.Hence,this system is a potential candidate for the next generation of radio navigation after GPS.

  18. Communication-based positioning systems: past, present and prospects

    Science.gov (United States)

    Ma, Guan-Yi; Wan, Qing-Tao; Gan, Tong

    2012-06-01

    This paper reviews positioning systems in the context of communication systems. First, the basic positioning technique is described for location based service (LBS) in mobile communication systems. Then the high integrity global positioning system (iGPS) is introduced in terms of aspects of what it is and how the low Earth orbit (LEO) Iridium telecommunication satellites enhance the global positioning system (GPS). Emphasis is on the Chinese Area Positioning System (CAPS) which is mainly based on commercial geostationary (GEO) communication satellites, including decommissioned GEO and inclined geosynchronous communication satellites. Characterized by its low cost, high flexibility, wide-area coverage and ample frequency resources, a distinctive feature of CAPS is that its navigation messages are generated on the ground, then uploaded to and forwarded by the communication satellites. Fundamental principles and key technologies applied in the construction of CAPS are presented in detail from the CAPS validation phase to its experimental system setup. A prospective view of CAPS has concluded it to be a seamless, high accuracy, large capacity navigation and communication system which can be achieved by expanding it world wide and enhancing it with LEO satellites and mobile base stations. Hence, this system is a potential candidate for the next generation of radio navigation after GPS.

  19. ATCOM: Automatically Tuned Collective Communication System for SMP Clusters

    Energy Technology Data Exchange (ETDEWEB)

    Meng-Shiou Wu

    2005-12-17

    Conventional implementations of collective communications are based on point-to-point communications, and their optimizations have been focused on efficiency of those communication algorithms. However, point-to-point communications are not the optimal choice for modern computing clusters of SMPs due to their two-level communication structure. In recent years, a few research efforts have investigated efficient collective communications for SMP clusters. This dissertation is focused on platform-independent algorithms and implementations in this area. There are two main approaches to implementing efficient collective communications for clusters of SMPs: using shared memory operations for intra-node communications, and overlapping inter-node/intra-node communications. The former fully utilizes the hardware based shared memory of an SMP, and the latter takes advantage of the inherent hierarchy of the communications within a cluster of SMPs. Previous studies focused on clusters of SMP from certain vendors. However, the previously proposed methods are not portable to other systems. Because the performance optimization issue is very complicated and the developing process is very time consuming, it is highly desired to have self-tuning, platform-independent implementations. As proven in this dissertation, such an implementation can significantly out-perform the other point-to-point based portable implementations and some platform-specific implementations. The dissertation describes in detail the architecture of the platform-independent implementation. There are four system components: shared memory-based collective communications, overlapping mechanisms for inter-node and intra-node communications, a prediction-based tuning module and a micro-benchmark based tuning module. Each component is carefully designed with the goal of automatic tuning in mind.

  20. ATCOM: Automatically Tuned Collective Communication System for SMP Clusters

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Meng-Shiou [Iowa State Univ., Ames, IA (United States)

    2005-01-01

    Conventional implementations of collective communications are based on point-to-point communications, and their optimizations have been focused on efficiency of those communication algorithms. However, point-to-point communications are not the optimal choice for modern computing clusters of SMPs due to their two-level communication structure. In recent years, a few research efforts have investigated efficient collective communications for SMP clusters. This dissertation is focused on platform-independent algorithms and implementations in this area. There are two main approaches to implementing efficient collective communications for clusters of SMPs: using shared memory operations for intra-node communications, and overlapping inter-node/intra-node communications. The former fully utilizes the hardware based shared memory of an SMP, and the latter takes advantage of the inherent hierarchy of the communications within a cluster of SMPs. Previous studies focused on clusters of SMP from certain vendors. However, the previously proposed methods are not portable to other systems. Because the performance optimization issue is very complicated and the developing process is very time consuming, it is highly desired to have self-tuning, platform-independent implementations. As proven in this dissertation, such an implementation can significantly out-perform the other point-to-point based portable implementations and some platform-specific implementations. The dissertation describes in detail the architecture of the platform-independent implementation. There are four system components: shared memory-based collective communications, overlapping mechanisms for inter-node and intra-node communications, a prediction-based tuning module and a micro-benchmark based tuning module. Each component is carefully designed with the goal of automatic tuning in mind.

  1. Effects of picture exchange communication system on communication and behavioral anomalies in autism

    Directory of Open Access Journals (Sweden)

    Malhotra Shahzadi

    2010-01-01

    Full Text Available Communication skills deficits and stereotyped behaviors are frequently found among people with pervasive developmental disabilities like autism. These communication and behavioral oddities of autism are often considered to be difficult to treat and are challenging. Picture exchange communication system (PECS is a six-phase picture system based on applied behavior analysis and is specially designed to overcome these communication difficulties in children with autism by encouraging the child to be the communication initiator. The present paper throws light on the process of using PECS along with other traditional behavioral approaches in managing communication deficits and behavioral stereotypies in a seven-year-old male child diagnosed as having childhood autism. The identified target behaviors of repeated head turning, flapping his hands, poor communication skills were assessed using various rating scales including visual analogue scale as per clinician observation and parental reports and managed using PECS as an adjunct to traditional behavioral techniques of contingency management, differential reinforcement, task direction and reprimand. Outcome was assessed using same tools after thirty-two sessions of interventions spread over three months. Significant improvements of around 60% were observed in the target behaviors.

  2. Effects of Picture Exchange Communication System on Communication and Behavioral Anomalies in Autism

    Science.gov (United States)

    Malhotra, Shahzadi; Rajender, Gaurav; Bhatia, Manjeet S.; Singh, Tej B.

    2010-01-01

    Communication skills deficits and stereotyped behaviors are frequently found among people with pervasive developmental disabilities like autism. These communication and behavioral oddities of autism are often considered to be difficult to treat and are challenging. Picture exchange communication system (PECS) is a six-phase picture system based on applied behavior analysis and is specially designed to overcome these communication difficulties in children with autism by encouraging the child to be the communication initiator. The present paper throws light on the process of using PECS along with other traditional behavioral approaches in managing communication deficits and behavioral stereotypies in a seven-year-old male child diagnosed as having childhood autism. The identified target behaviors of repeated head turning, flapping his hands, poor communication skills were assessed using various rating scales including visual analogue scale as per clinician observation and parental reports and managed using PECS as an adjunct to traditional behavioral techniques of contingency management, differential reinforcement, task direction and reprimand. Outcome was assessed using same tools after thirty-two sessions of interventions spread over three months. Significant improvements of around 60% were observed in the target behaviors. PMID:21716776

  3. How to maximize science communication efficacy by combining old and new media

    Science.gov (United States)

    Nuccitelli, D. A.; Cook, J.

    2014-12-01

    Traditional science communication approaches (such as relying on university press releases about new scientific publications), and new communication approaches (such as utilizing infographics and social media), can each reach a wide audience when successful. However, probability of successful the science communication can be amplified by taking advantage of both traditional and new media, especially when 'sticky' messaging techniques are applied. The example of Cook et al., 2013 (C13), which found a 97% consensus in the peer-reviewed climate literature on human-caused global warming, is considered. C13 implemented this optimal combined communications approach strategy and became the most-downloaded study in all Institute of Physics journals, with over 200,000 downloads to date. Due to the effective 'sticky' messaging approaches implemented by the study authors, its results received broad coverage from international media and reached millions of people via social media. Strategies to avoid misrepresentations of one's work while maximizing the communications efficacy of its key points will also be discussed.

  4. Combined Solar and Wind Energy Systems

    Science.gov (United States)

    Tripanagnostopoulos, Y.; Souliotis, M.; Makris, Th.

    2010-01-01

    In this paper we present the new concept of combined solar and wind energy systems for buildings applications. Photovoltaics (PV) and small wind turbines (WTs) can be install on buildings, in case of sufficient wind potential, providing the building with electricity. PVs can be combined with thermal collectors to form the hybrid photovoltaic/thermal (PV/T) systems. The PVs (or the PV/Ts) and WT subsystems can supplement each other to cover building electrical load. In case of using PV/T collectors, the surplus of electricity, if not used or stored in batteries, can increase the temperature of the thermal storage tank of the solar thermal unit. The description of the experimental set-up of the suggested PV/T/WT system and experimental results are presented. In PV/T/WT systems the output from the solar part depends on the sunshine time and the output of the wind turbine part depends on the wind speed and is obtained any time of day or night. The use of the three subsystems can cover a great part of building energy load, contributing to conventional energy saving and environment protection. The PV/T/WT systems are considered suitable in rural and remote areas with electricity supply from stand-alone units or mini-grid connection. PV/T/WT systems can also be used in typical grid connected applications.

  5. A fast microprocessor communication network design for interprocessor communications for an integrated flight control system

    Science.gov (United States)

    Kelly, G. L.; Jiang, P.-W.

    1982-01-01

    A node design with connectivity four is presented whose communication processor handles data at four million bits/sec on each of the four channels into the node, and on each of the four channels out of the node, for a total node capacity of 32 million bits/sec. An integrated flight control system real-time application of this communication network design is discussed. It is shown that such high speed node communication hardware, arranged in the topological configuration of a minimum diameter graph with connectivity four and all links active, has good potential for real time control applications requiring reliability, availability, and survivability characteristics.

  6. The transmission link of CAPS navigation and communication system

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Chinese Area Positioning System (CAPS) is based on communication satellites with integrated capability, which is different from the Global Positioning System (GPS), the International Maritime Satellite Organization (Inmarsat) and so on. CAPS works at C-band, and its navigation information is not directly generated from the satellite, but from the master control station on the ground and transmitted to users via the satellite. The slightly inclined geostationary-satellite orbit (SIGSO) satellites are adopted in CAPS. All of these increase the difficulty in the design of the system and terminals. In this paper, the authors study the CAPS configuration parameters of the navigation master control station, information transmission capability, and the selection of the antenna aperture of the communication center station, as well as the impact of satellite parameters on the whole communication system from the perspective of the transmission link budget. The conclusion of availability of the CAPS navigation system is achieved. The results show that the CAPS inbound communication system forms a new low-data-rate satellite communication system, which can accommodate mass communication terminals with the transmission rate of no more than 1 kbps for every terminal. The communication center station should be configured with a large-aperture antenna (about 10-15 m); spread spectrum com- munication technology should be used with the spreading gain as high as about 40 dB; reduction of the satellite transponder gain attenuation is beneficial to improving the signal-to-noise ratio of the system, with the attenuation value of 0 or 2 dB as the best choice. The fact that the CAPS navigation system has been checked and accepted by the experts and the operation is stable till now clarifies the rationality of the analysis results. The fact that a variety of experiments and applications of the satellite communication system designed according to the findings in this paper have been

  7. Relating Communications Mode Choice and Teamwork Quality: Conversational versus Textual Communication in IT System and Software Development Teams

    Science.gov (United States)

    Smith, James Robert

    2012-01-01

    This cross-sectional study explored how IT system and software development team members communicated in the workplace and whether teams that used more verbal communication (and less text-based communication) experienced higher levels of collaboration as measured using the Teamwork Quality (TWQ) scale. Although computer-mediated communication tools…

  8. Relating Communications Mode Choice and Teamwork Quality: Conversational versus Textual Communication in IT System and Software Development Teams

    Science.gov (United States)

    Smith, James Robert

    2012-01-01

    This cross-sectional study explored how IT system and software development team members communicated in the workplace and whether teams that used more verbal communication (and less text-based communication) experienced higher levels of collaboration as measured using the Teamwork Quality (TWQ) scale. Although computer-mediated communication tools…

  9. INTENTIONAL COMBINATIVITY OF COMMUNICATIVE STRATEGIES AND TACTICS AS A FACTOR OFA SUCCESSFUL POLITICAL SELF-PRESENTATION

    Directory of Open Access Journals (Sweden)

    Mishchuk O. N.

    2016-06-01

    Full Text Available Combinativity of speech strategies and tactics in a public political address as markers of a general intention within a framework of a background strategy of self-presentation is considered. The research methods of speech architectonic are determined. Structural and composite elements of a presidential speech are analyzed. Communicative strategies and tactics as means of an effective self-presentation are described

  10. Research on laser induced acoustic source based underwater communication system

    Science.gov (United States)

    Lei, Lihua; Zhou, Ju; Zhang, Lei; Wan, Xiaoyun

    2016-10-01

    Acoustic transducers are traditionally used to generate underwater acoustical energy with the device physically immersed in water. Novel methods are required for communicating from an in-air platform or surface vessel to a submerged vessel. One possible noncontact downlink communication system involves the use of laser induced acoustic source. The most common mechanisms of opto-acoustic energy conversion are, by order of increasing laser energy density and efficiency, thermal expansion, surface evaporation and optical breakdown. The laser induced acoustic source inherently bears the obvious advantage of not requiring any physical transducer in the medium. At the same time, acoustic energy propagation is efficient in water, whereas optical energy propagate well in air, leading to a more efficiency opto-acoustic communication method. In this paper, an opto-acoustic underwater Communication system is described, aiming to study and analysis whether laser induced sound could achieve good performance for effective communication in practical application.

  11. Self-Organizing OFDMA System for Broadband Communication

    Science.gov (United States)

    Roy, Aloke (Inventor); Anandappan, Thanga (Inventor); Malve, Sharath Babu (Inventor)

    2016-01-01

    Systems and methods for a self-organizing OFDMA system for broadband communication are provided. In certain embodiments a communication node for a self organizing network comprises a communication interface configured to transmit data to and receive data from a plurality of nodes; and a processing unit configured to execute computer readable instructions. Further, computer readable instructions direct the processing unit to identify a sub-region within a cell, wherein the communication node is located in the sub-region; and transmit at least one data frame, wherein the data from the communication node is transmitted at a particular time and frequency as defined within the at least one data frame, where the time and frequency are associated with the sub-region.

  12. IEPLC Framework, Automated Communication in a Heterogeneous Control System Environment

    CERN Document Server

    Locci, F

    2014-01-01

    In CERN accelerators control system several components are essential such as: Programmable Logic Controller (PLC), PCI Extensions for Instrumentation (PXI), and other micro-controller families. Together with their weaknesses and their strength points they typically present custom communication protocols and it is therefore difficult to federate them into the control system using a single communication strategy. Furthermore this dependency to the physical device interfaces and protocols makes most of the code not reusable and the replacement of old technology a difficult problem. The purpose of IEPLC ([1]) is to mitigate the communication issues given by this heterogeneity; it proposes a framework to define communication interfaces in a hardware independent manner. In addition it automatically generates all the resources needed on master side (typically represented by a FEC: Front-End Computer) and slave side (typically represented by the controller) to implement a common and generic Ethernet communication. Th...

  13. 77 FR 28797 - Redundancy of Communications Systems: Backup Power Private Land Mobile Radio Services: Selection...

    Science.gov (United States)

    2012-05-16

    ..., Communications common carriers, Communications equipment, Radio, Telecommunications, Telephone, Television... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Parts 12 and 90 Redundancy of Communications Systems: Backup Power Private Land...

  14. Smart Data Node in the Sky (SDNITS): communications system

    Science.gov (United States)

    Kantak, A.; Lansing, F.

    2003-01-01

    In this paper we will discuss: the steps for adequately designing such a complex telecommunications system 'Smart Data Node In The Sky (SDNITS)'; algorithm development for this process; specifications to be levied on the interfacing subsystems; type of the system e.g., the usual Radio Frequency system or a laser communications system.

  15. Smart Data Node in the Sky (SDNITS): communications system

    Science.gov (United States)

    Kantak, A.; Lansing, F.

    2003-01-01

    In this paper we will discuss: the steps for adequately designing such a complex telecommunications system 'Smart Data Node In The Sky (SDNITS)'; algorithm development for this process; specifications to be levied on the interfacing subsystems; type of the system e.g., the usual Radio Frequency system or a laser communications system.

  16. Concurrent System Engineering and Risk Reduction for Dual-Band (RF/optical) Spacecraft Communications

    Science.gov (United States)

    Fielhauer, Karl, B.; Boone, Bradley, G.; Raible, Daniel, E.

    2012-01-01

    This paper describes a system engineering approach to examining the potential for combining elements of a deep-space RF and optical communications payload, for the purpose of reducing the size, weight and power burden on the spacecraft and the mission. Figures of merit and analytical methodologies are discussed to conduct trade studies, and several potential technology integration strategies are presented. Finally, the NASA Integrated Radio and Optical Communications (iROC) project is described, which directly addresses the combined RF and optical approach.

  17. Reasons for Picture Archiving and Communication System (PACS ...

    African Journals Online (AJOL)

    Reasons for Picture Archiving and Communication System (PACS) data security ... breaches are nonintentionally committed by well-meaning employees during ... Methods: A closed-ended questionnaire was used to collect quantitative data ...

  18. Wireless Intra-vehicle Communication System (WICS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Invocon's Wireless Intra-vehicle Communication System (WICS) is being designed as an enabling technology for low-cost launch vehicles. It will reduce the cost of...

  19. A communication-channel-based representation system for software

    NARCIS (Netherlands)

    Demirezen, Zekai; Tanik, Murat M.; Aksit, Mehmet; Skjellum, Anthony

    2014-01-01

    We observed that before initiating software development the objectives are minimally organized and developers introduce comparatively higher organization throughout the design process. To be able to formally capture this observation, a new communication channel representation system for software is

  20. Workload characterization for the space station data communications system

    Science.gov (United States)

    Sevcik, K. C.

    1986-01-01

    NASA plans to launch a permanent manned space station in the early 1990's. The station will be used to support a wide variety of activities involving Earth and space observation, satellite maintenance, scientific experimentation, and commercial manufacturing. The control and monitoring of many of these activities will require extensive computer and communications system support. In order to identify an appropriate computer and communication system for supporting the space station, an attempt to characterize the space station's data communications subsystem workload is currently underway. Some of the special aspects of the workload characterization problem are discussed in connection with the space station, and some possible approaches are presented.

  1. Mode-Locked Semiconductor Lasers for Optical Communication Systems

    DEFF Research Database (Denmark)

    Yvind, Kresten; Larsson, David; Oxenløwe, Leif Katsuo

    2005-01-01

    We present investigations on 10 and 40 GHz monolithic mode-locked lasers for applications in optical communications systems. New all-active lasers with one to three quantum wells have been designed, fabricated and characterized.......We present investigations on 10 and 40 GHz monolithic mode-locked lasers for applications in optical communications systems. New all-active lasers with one to three quantum wells have been designed, fabricated and characterized....

  2. The development of multimedia communication system for electric power company

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Hee Gon; Kim, Seong Bok [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

    1995-12-31

    It is a final report of the research project that is a development of PC-LAN based multimedia desktop conference system, which is research on the essential technologies and application and development of multimedia communication services for electric power company. This report is consisted of -Survey and study of the multimedia related technologies, -Multimedia communication protocols and network configurations, and -Design, developments of pilot model, evaluation, and applications of multimedia conference system. (author). 112 refs., 250 figs.

  3. 4th International Conference on Communications, Signal Processing, and Systems

    CERN Document Server

    Mu, Jiasong; Wang, Wei; Zhang, Baoju

    2016-01-01

    This book brings together papers presented at the 4th International Conference on Communications, Signal Processing, and Systems, which provides a venue to disseminate the latest developments and to discuss the interactions and links between these multidisciplinary fields. Spanning topics ranging from Communications, Signal Processing and Systems, this book is aimed at undergraduate and graduate students in Electrical Engineering, Computer Science and Mathematics, researchers and engineers from academia and industry as well as government employees (such as NSF, DOD, DOE, etc).

  4. Shared Communications: Volume 2. In-Depth Systems Research

    Energy Technology Data Exchange (ETDEWEB)

    Truett, LF

    2004-09-22

    This report is the second of two documents that examine the literature for actual examples of organizations and agencies that share communications resources. While the primary emphasis is on rural, intelligent transportation system (ITS) communications involving transit, examples will not be limited to rural activities, nor to ITS implementation, nor even to transit. In addition, the term ''communication'' will be broadly applied to include all information resources. The first document of this series, ''Shared Communications: Volume I. A Summary and Literature Review'', defines the meaning of the term ''shared communication resources'' and provides many examples of agencies that share resources. This document, ''Shared Communications: Volume II. In-Depth Systems Research'', reviews attributes that contributed to successful applications of the sharing communication resources concept. A few examples of each type of communication sharing are provided. Based on the issues and best practice realworld examples, recommendations for potential usage and recommended approaches for field operational tests are provided.

  5. Self-Homodyne Detection in Optical Communication Systems

    Directory of Open Access Journals (Sweden)

    Benjamin J. Puttnam

    2014-05-01

    Full Text Available We review work on self-homodyne detection (SHD for optical communication systems. SHD uses a transmitted pilot-tone (PT, originating from the transmitter laser, to exploit phase noise cancellation at a coherent receiver and to enable transmitter linewidth tolerance and potential energy savings. We give an overview of SHD performance, outlining the key contributors to the optical signal-to-noise ratio penalty compared to equivalent intradyne systems, and summarize the advantages, differences and similarities between schemes using polarization-division multiplexed PTs (PDM-SHD and those using space-division multiplexed PTs (SDM-SHD. For PDM-SHD, we review the extensive work on the transmission of advanced modulation formats and techniques to minimize the trade-off with spectral efficiency, as well as recent work on digital SHD, where the SHD receiver is combined with an polarization-diversity ID front-end receiver to provide both polarization and modulation format alignment. We then focus on SDM-SHD systems, describing experimental results using multi-core fibers (MCFs with up to 19 cores, including high capacity transmission with broad-linewidth lasers and experiments incorporating SDM-SHD in networking. Additionally, we discuss the requirement for polarization tracking of the PTs at the receiver and path length alignment and review some variants of SHD before outlining the future challenges of self-homodyne optical transmission and gaps in current knowledge.

  6. Tunnel radio communications system at Stanford Linear Accelerator Center

    Energy Technology Data Exchange (ETDEWEB)

    Struven, W.C.

    1980-07-01

    A unique single frequency, dual daisy chain tunnel radio communication system has been developed for use in our new Positron-Electron Storage Ring. Communications are possible between portables in the underground ring and between a portable in the ring and all control rooms on the site. The system is designed as a wide band facility and therefore can carry many simplex and duplex transmissions. This system utilizes TV twinlead as a distributed antenna and repeater amplifiers to cover more than 7000 feet of underground tunnel. The design philosophy, tests and initial design are discussed and contrasted with the final implementation of the system. Future uses of the system are discussed.

  7. A Study of Synchronization Techniques for Optical Communication Systems

    Science.gov (United States)

    Gagliardi, R. M.

    1975-01-01

    The study of synchronization techniques and related topics in the design of high data rate, deep space, optical communication systems was reported. Data cover: (1) effects of timing errors in narrow pulsed digital optical systems, (2) accuracy of microwave timing systems operating in low powered optical systems, (3) development of improved tracking systems for the optical channel and determination of their tracking performance, (4) development of usable photodetector mathematical models for application to analysis and performance design in communication receivers, and (5) study application of multi-level block encoding to optical transmission of digital data.

  8. Communication

    NARCIS (Netherlands)

    Sigafoos, J.; Lancioni, G.E.; O'Reilly, M.F.; Lang, R.; Singh, N.N.; Didden, H.C.M.; Green, V.A.; Marschik, P.B.

    2016-01-01

    Communication disorders are common among people with intellectual disabilities. Consequently, enhancing the communication skills of such individuals is a major intervention priority. This chapter reviews the nature and prevalence of the speech, language, and communication problems associated with

  9. Laser Communication Demonstration System (LCDS) and future mobile satellite services

    Science.gov (United States)

    Chen, Chien-Chung; Wilhelm, Michael D.; Lesh, James R.

    1995-01-01

    The Laser Communications Demonstration System (LCDS) is a proposed in-orbit demonstration of high data rate laser communications technology conceived jointly by NASA and U.S. industry. The program objectives are to stimulate industry development and to demonstrate the readiness of high data rate optical communications in Earth orbit. For future global satellite communication systems using intersatellite links, laser communications technology can offer reduced mass and power requirements and higher channel bandwidths without regulatory constraints. As currently envisioned, LCDS will consist of one or two orbiting laser communications terminals capable of demonstrating high data rate (greater than 750Mbps) transmission in a dynamic space environment. Two study teams led by Motorola and Ball Aerospace are currently in the process of conducting a Phase A/B mission definition study of LCDS under contracts with JPL/NASA. The studies consist of future application survey, concept and requirements definition, and a point design of the laser communications flight demonstration. It is planned that a single demonstration system will be developed based on the study results. The Phase A/B study is expected to be completed by the coming June, and the current results of the study are presented in this paper.

  10. Development of a web-based picture archiving and communication system using satellite data communication.

    Science.gov (United States)

    Hwang, S; Lee, J; Kim, H; Lee, M

    2000-01-01

    Using the JAVA language we have developed a Web-based picture archiving and communication system (PACS) which allows a remote hospital to access medical images. An asymmetric satellite data communication system (ASDCS) provided a receive-only link for data delivery and a conventional terrestrial link (which could be the conventional telephone network) allowed data transmission. The satellite communication link was 10-30 times faster than the conventional terrestrial link. To increase image transmission speeds over the Internet connection, JPEG and wavelet compression methods were used. The resulting images were evaluated quantitatively by measuring the peak signal:noise ratio and qualitatively by radiologists. Compression ratios of 10:1 or less were deemed acceptable for diagnostic purposes. The system appears to be suitable for teleradiology and telemedicine.

  11. Integrated source and channel encoded digital communication system design study

    Science.gov (United States)

    Alem, W. K.; Huth, G. K.; Simon, M. K.

    1978-01-01

    The particular Ku-band carrier, PN despreading, and symbol synchronization strategies, which were selected for implementation in the Ku-band transponder aboard the orbiter, were assessed and evaluated from a systems performance viewpoint, verifying that system specifications were met. A study was performed of the design and implementation of tracking techniques which are suitable for incorporation into the Orbiter Ku-band communication system. Emphasis was placed on maximizing tracking accuracy and communication system flexibility while minimizing cost, weight, and system complexity of Orbiter and ground systems hardware. The payload communication study assessed the design and performance of the forward link and return link bent-pipe relay modes for attached and detached payloads. As part of this study, a design for a forward link bent-pipe was proposed which employs a residual carrier but which is tracked by the existing Costas loop.

  12. ISSUES AND RECENT TRENDS IN VEHICLE SAFETY COMMUNICATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Sadayuki TSUGAWA

    2005-01-01

    Full Text Available This paper surveys the research on the applications of inter-vehicle communications, the issues of the deployment and technology, and the current status of inter-vehicle communications projects in Europe, the United States and Japan. The inter-vehicle communications, defined here as communications between on-board ITS computers, improve road traffic safety and efficiency by expanding the horizon of the drivers and on-board sensors. One of the earliest studies on inter-vehicle communications began in Japan in the early 1980s. The inter-vehicle communications play an essential role in automated platooning and cooperative driving systems developed since the 1990's by enabling vehicles to obtain data that would be difficult or impossible to measure with on-board sensors. During these years, interest in applications for inter-vehicle communications increased in the EU, the US and Japan, resulting in many national vehicle safety communications projects such as CarTALK2000 in the EU and VSCC in the US. The technological issues include protocol and communications media. Experiments employ various kinds of protocols and typically use infrared, microwave or millimeter wave media. The situation is ready for standardization. The deployment strategy is another issue. To be feasible, deployment should begin with multiple rather than single services that would work even at a low penetration rate of the communication equipment. In addition, non-technological, legal and institutional issues remained unsolved. Although inter-vehicle communications involve many issues, such applications should be promoted because they will lead to safer and more efficient automobile traffic.

  13. A MODEL FOR COMMUNICATION BETWEEN AN ERP SYSTEM AND A GAMIFICATION SYSTEM

    Directory of Open Access Journals (Sweden)

    Julian Vasilev

    2016-03-01

    Full Text Available The purpose of this article is displaying a model for communication between an ERP system and a gamification system. The research is focused on ERP systems and gamification systems. The subjects of this research are the information links providing communication between the two systems. The article offers a unique technological solution for communication. It may be applied by a wide range of companies wishing to implement communication between an ERP system and a gamification system. The scope of this study is limited to the possibilities of communication between the two systems. The communication between the two systems is argued to be carried out by two web services. The proposal is given at a high level of abstraction. It may find a wide multiplier effect in many enterprises.

  14. Communications Solutions for Heterogeneous Systems Based on SOA

    Science.gov (United States)

    Wei, Xianmin

    In order to address the gaps which widely used in business application architecture and problems of heterogeneous system communication, this paper provides a standardized framework of SOA, built in the application of a loose coupling between systems "server + proxy" data exchange platform, to achieve heterogeneous data exchange and data sharing, and developed a business based on Web services platform, making full use of the Web service, which makes the system has good scalability and maintainability, to solve the problem of heterogeneous system communication and widely used to make up for the current architecture lack of business applications.

  15. Blind Recognition Algorithm of Turbo Codes for Communication Intelligence Systems

    Directory of Open Access Journals (Sweden)

    Ali Naseri

    2011-11-01

    Full Text Available Turbo codes are widely used in land and space radio communication systems, and because of complexity of structure, are custom in military communication systems. In electronic warfare, COMINT systems make attempt to recognize codes by blind ways. In this Paper, the algorithm is proposed for blind recognition of turbo code parameters like code kind, code-word length, code rate, length of interleaver and delay blocks number of convolution code. The algorithm calculations volume is0.5L3+1.25L, therefore it is suitable for real time systems.

  16. Communicating to promote justice in the modern health care system.

    Science.gov (United States)

    Kreps, G L

    1996-01-01

    The systemic prejudices and biases that often limit the effectiveness of health care delivery are examined. How the inherent imbalance in control between consumers and providers of health care, based on the micropolitics of sharing relevant health information, perpetuates a system of marginalization and alienation within health care delivery systems is discussed. Communication barriers that often confront many stigmatized groups of health care consumers, such as the poor, people with AIDS, minorities, the ill elderly, and women, are identified. Such prejudicial treatment is framed within a cultural ideologies model, leading to identification of communication strategies for promoting justice in the modern health care system and enhancing the quality of health care delivery.

  17. Communication Standards Suitable for MES Systems Designed for SMES

    Directory of Open Access Journals (Sweden)

    Ondřej WINKLER

    2009-06-01

    Full Text Available A MES (Manufacturing Execution System is a system that large companies use to measure or control critical production activities. Individual parts of this system can be used as a model for development of tools suitable for small and medium enterprises (SMEs. It can demonstrate how manufacturing systems works and which communication standards are usable. The communication standards enable data acquisition, data processing, storing and their conversion for any production report. Furthermore, interfaces for web clients allow displaying the raw or transformed data as a text or a graphic chart. The development of tools for an access to the data retrieved from MES software is described in this paper.

  18. Augmentative And Alternative Communication Systems For Post-Stroke Patients With Severe Communication And Motor Impairment

    Directory of Open Access Journals (Sweden)

    Talieh Zarifian

    2017-02-01

    Full Text Available Background and aims: Adults with acquired neurological disorders (stroke, Traumatic Brain Injury ... develop their verbal communication and literacy capabilities as typical speakers and writers. They use these skills to participate academically, vocationally, recreationally, and socially. Depending upon their neurological condition, they gradually or suddenly lose their speech or language capabilities and are required to rely on Augmentative and Alternative Communication (AAC systems to meet their communication needs. In addition to the loss of their spoken communication, the impact of their neurological condition on their participation patterns is potentially profound with reduced ability to care for themselves, a reduction or loss of employment, and usually a sudden or gradual restriction of their social networks. AAC is an umbrella term that encompasses the communication methods used to supplement or replace speech or writing for those with impairments in the production or comprehension of spoken or written language. During the past five decades, AAC technologies have been developed to compensate for these natural communication losses.      Stroke is one of the main causes of disability in the world. About 20% of stroke patients experience aphasia, with 20-30% of these individuals exhibiting severe communication deficits for at least a portion of their recovery period. Augmentative and Alternative Communication (AAC encompasses the communication methods used to supplement or replace speech or writing for those with impairments in the production of spoken or written language.  Specifically designed Human Computer Interfaces (HCI, as an assistive technology, provides new channels of communication for patients with aphasia, dysarthria, and dyspraxia, when accompanied by movement impairments.       In this workshop after stating a science review of the following types of issues: AAC acceptance (individually, culturally; AAC availability

  19. An FPGA Implementation of Secured Steganography Communication System

    Directory of Open Access Journals (Sweden)

    Ahlam Mahmood

    2014-04-01

    Full Text Available Steganography is the idea of hiding secret message in multimedia cover which will be transmitted through the Internet. The cover carriers can be image, video, sound or text data. This paper presents an implementation of color image steganographic system on Field Programmable Gate Array and the information hiding/extracting techniques in various images. The proposed algorithm is based on merge between the idea from the random pixel manipulation methods and the Least Significant Bit (LSB matching of Steganography embedding and extracting method.  In a proposed steganography hardware approach, Linear Feedback Shift Register (LFSR method has been used in stego architecture to hide the information in the image. The LFSRs are utilized in this approach as address generators. Different LFSR arrangements using different connection unit have been implemented at the hardware level for hiding/extracting the secret data. Multilayer embedding is implemented in parallel manner with a three-stage pipeline on FPGA.  This work showed attractive results especially in the high throughputs, better stego-image quality, requires little calculation and less utilization of FPGA area. The imperceptibility of the technique combined with high payload, robustness of embedded data and accurate data retrieval renders the proposed Steganography system is suitable for covert communication and secure data transmission applications

  20. Estimation of the demand for public services communications. [market research and economic analysis for a communications satellite system

    Science.gov (United States)

    1976-01-01

    Market analyses and economic studies are presented to support NASA planning for a communications satellite system to provide public services in health, education, mobile communications, data transfer, and teleconferencing.

  1. Integrated source and channel encoded digital communications system design study

    Science.gov (United States)

    Huth, G. K.

    1974-01-01

    Studies on the digital communication system for the direct communication links from ground to space shuttle and the links involving the Tracking and Data Relay Satellite (TDRS). Three main tasks were performed:(1) Channel encoding/decoding parameter optimization for forward and reverse TDRS links,(2)integration of command encoding/decoding and channel encoding/decoding; and (3) modulation coding interface study. The general communication environment is presented to provide the necessary background for the tasks and to provide an understanding of the implications of the results of the studies.

  2. CCPA: Component-based communication protocol architecture for embedded systems

    Institute of Scientific and Technical Information of China (English)

    DAI Hong-jun; CHEN Tian-zhou; CHEN Chun

    2005-01-01

    For increased and various communication requirements of modem applications on embedded systems, general purpose protocol stacks and protocol models are not efficient because they are fixed to execute in the static mode. We present the Component-Based Communication Protocol Architecture (CCPA) to make communication dynamic and configurable. It can develop, test and store the customized components for flexible reuse. The protocols are implemented by component assembly and support by configurable environments. This leads to smaller memory, more flexibility, more reconfiguration ability, better concurrency, and multiple data channel support.

  3. Modelling of Transmitter & Receiver for VSAT Communication System

    Directory of Open Access Journals (Sweden)

    Sanjida Sharmin Mohona

    2015-02-01

    Full Text Available The Satellite communication is an essential part of telecommunication systems which carrying large amount of data (internet, e-mail and telephone traffic in addition to TV signals. Very small aperture terminal (VSAT is widely used for these purposes. This paper aims to provide the framework of VSAT technology in the evolving context of satellite communications in terms of network configuration, services, economics and operational aspects. This paper presents the modelling and simulation aspects of communication blocks of VSAT which can be used in different types of network topology and also includes the numerical results simulated by MATLAB.

  4. COMMUNICATIONS

    CERN Multimedia

    L. Taylor and D. Barney

    2010-01-01

    CMS Centres, Outreach and the 7 TeV Media Event The new CMS Communications group is now established and is addressing three areas that are critical to CMS as it enters the physics operations phase: - Communications Infrastructure, including almost 50 CMS Centres Worldwide, videoconferencing systems, and CERN meeting rooms - Information systems, including the internal and external Web sites as well as the document preparation and management systems - Outreach and Education activities, including working with print, radio and TV media, visits to CMS, and exhibitions. The group has been active in many areas, with the highest priority being accorded to needs of CMS operations and preparations for the major media event planned for 7 TeV collisions. Unfortunately the CMS Centre@CERN suffered a major setback when, on 21st December, a cooling water pipe froze and burst on the floor above the CMS Centre main room. Water poured through the ceiling, flooding the floor and soaking some of the consoles, before e...

  5. Massive MIMO-OFDM indoor visible light communication system downlink architecture design

    Science.gov (United States)

    Lang, Tian; Li, Zening; Chen, Gang

    2014-10-01

    Multiple-input multiple-output (MIMO) technique is now used in most new broadband communication system, and orthogonal frequency division multiplexing (OFDM) is also utilized within current 4th generation (4G) of mobile telecommunication technology. With MIMO and OFDM combined, visible light communication (VLC) system's diversity gain is increase, yet system capacity for dispersive channels is also enhanced. Moreover, with the emerging massive MIMO-OFDM VLC system, there are significant advantages than smaller systems' such as channel hardening, further increasing of energy efficiency (EE) and spectral efficiency (SE) based on law of large number. This paper addresses one of the major technological challenges, system architecture design, which was solved by semispherical beehive structure (SBS) receiver and so that diversity gain can be identified and applied in Massive MIMO VLC system. Simulation results shows that the proposed design clearly presents a spatial diversity over conventional VLC systems.

  6. Multi-platform laser communication networking optical antenna system design

    Science.gov (United States)

    Zhang, Tao

    2016-10-01

    In this paper, a new conclusion based on rotating parabolic model and a different scheme of laser communication networking antenna system has been put forward in the paper. Based on rotating parabolic antenna, a new theory of the optical properties have been deduced, which can realize larger dynamic, duplex, networking communications among multiple platforms in 360° azimuth and pitch range. Meanwhile, depending on the operation mode of the system, multiple mathematical optimization models have been established. Tracking communication range, emission energy efficiency and receiving energy efficiency have been analyzed and optimized. Relationship among opening up and low apertures, the lens unit aperture, focal length of lens unit as well as rotating parabolic focal length have been analyzed. Tracking pitching range and emission energy utilization has carried on the theoretical derivation and optimization and networking platform link between energy receiver and transmitter has been analyzed. Taking some parameters of this new system into calculation, optimized results can be utilized with MATLAB software for its application and system of communication engineering. The rotating parabolic internal can form a hollow structure, which is utilized for miniaturization, light-weighted design and realize duplex communication in a wide range and distance. Circular orbit guidance is the modern way used in dynamic tracking system. The new theory and optical antenna system has widespread applications value as well.

  7. TRANSMISSION OF DATA USING POWER LINE CARRIER COMMUNICATION SYSTEM

    Directory of Open Access Journals (Sweden)

    Jovita Serrao

    2012-11-01

    Full Text Available This paper serves as a general and technical reference to transmission of data using a power line carrier communication system which is a preferred choice over Wireless or other Home Networking technologies due to the ease of installation, availability of AC outlets, higher throughput, low cost, reliability and security. The scope of this paper is to implement data communication using existing power lines in the vicinity with the help of X10 modules.

  8. Ultrasonic wireless broadband communication system for underwater applications

    OpenAIRE

    Martins, Marcos Silva

    2013-01-01

    Tese de doutoramento do Programa Doutoral em Engenharia Eletrónica e de Computadores Underwater wireless communication systems are becoming a priority in terms of research and technological development due to the increasing demand for exploring the oceans’ potential in areas such as pharmaceutical, oil, minerals, environmental and biodiversity. This demand is increasing exponentially with the need for high data rate and near-real-time communications between submerged mobile and...

  9. Real-time Data Communication in Photoelectric Image Detection System

    Institute of Scientific and Technical Information of China (English)

    CHEN Wen-tao; LIU Yong-gui; HUANG Min

    2006-01-01

    High speed data communication between digital signal processor and the host is required to meet the demand of most real-time systems. PCI bus technology is a solution of this problem. The principle of data communication based on PCI has been explained. Meanwhile,the technology of data transfer between synchronous dynamic RAM(SDRAM) and an mapping space of on-chip memory(L2) by expansion direct memory access(EDMA) has also been realized.

  10. Communication architecture system for fiber positioning of DESI spectrograph

    Science.gov (United States)

    Kaci, Karim; Glez-de-Rivera, Guillermo; Lopez-Colino, Fernando; Martinez-Garcia, M. Sofia; Masa, Jose L.; Garrido, Javier; Sanchez, Justo; Prada, Francisco

    2016-07-01

    This paper presents a design proposal for controlling the five thousand fiber positioners within the focal plate of the DESI instrument. Each of these positioners is a robot which allows positioning its optic fiber with a resolution within the range of few microns. The high number and density of these robots poses a challenge for handling the communication from a central control device to each of these five thousand. Furthermore, an additional restriction applies as the required time to communicate to every robot of its position must be smaller than a second. Additionally. a low energy consumption profile is also desired. Both wireless and wired communication protocols have been evaluated, proposing single-technology-based architectures and hybrid ones (a combination of them). Among the wireless solutions, ZigBee and CyFi have been considered. Using simulation tools these wireless protocols have been discarded as they do not allow an efficient communication. The studied wired protocols comprise I2C, CAN and Ethernet. The best solution found is a hybrid multilayer architecture combining both Ethernet and I2C. A 100 Mbps Ethernet based network is used to communicate the central control unit with ten management boards. Each of these boards is a low-cost, low-power embedded device that manages a thirty six degrees sector of the sensing plate. Each of these boards receives the positioning data for five hundred robots and communicate with each one through a fast mode plus I2C bus. This proposal allows to communicate the positioning information for all five thousand robots in 350 ms total.

  11. Communicating landslide risk by combining hazard and open infrastructure data in interactive visualizations

    Science.gov (United States)

    Tost, Jordi; Olen, Stephanie M.; Bookhagen, Bodo; Heidmann, Frank

    2017-04-01

    The DIGENTI project ("DIGitaler ENtscheiderTIsch für das Naturgefahrenmanagement auf Basis von Satellitendaten und Volunteered Geographic Information") has the goal of quantifying and communicating the threat of natural hazards in the Cesar and La Guajira departments of northeast Colombia. The end-goal of the project is to provide an interactive guide for policy and decision makers, and for disaster relief coordination. Over the last years, abundant research has been done in order to analyze risk and to provide relevant information that improves effectiveness in disaster management. The communication of natural hazards risk has traditionally been built upon the estimation of hazard maps. In the context of landslides, hazard maps are used to depict potential danger from landslides and visualize the possibility of future landsliding throughout a given area. Such hazard maps provide a static snapshot of the local estimated threat in a region. However, in mountainous regions, a sufficiently large landslide in remote mountainous areas may represent a potential threat to settlements located downstream of a landslide event. The research presented here proposes an approach to visualize and interactively explore landslide risk by combining static hazard maps, hydrologic networks, and OpenStreetMap data. We estimated the potential for hillslope instabilities scenarios in the region of interest by using the TanDEM-X World DEM to calculate a suite Factor of Safety (FOS) maps. The FOS estimates the ratio of total resisting and driving forces to hillslope mass movements. By combining the World DEM with other environmental data (e.g., the Harmonized World Soil Database), we were able to create a suite of high-resolution landslide potential maps for the region of interest. The suite of FOS maps are calculated based on user-selectable parameters (e.g, total mass sliding thickness) that are not well constrained by field observations. We additionally use the TanDEM-X World DEM to

  12. Modelling of Disturbing Efects within Communication Channel for Safety-Related Communication System

    Directory of Open Access Journals (Sweden)

    Maria Franekova

    2007-01-01

    Full Text Available The aim of the paper is using of modelling within development of safety–related communication systems presented in the areas where guaranty of safety integrity level is required. In the paper basic principles used in the process of safety evaluation in closed transmission systems are summarised. Dangerous states of system are mainly caused by random failures of HW within non-trusted transmission system, by electromagnetic interference caused with noise or interferences and by systematic failures within specification of system. Main part of paper describes the simulation of disturbing effects within communication channel via programme Matlab, relations for determination of probability of undetected errors of code words with using block codes and results of residual error rate for Hamming code.

  13. Infrastructure design of a picture archiving and communication system.

    Science.gov (United States)

    Huang, H K; Taira, R K

    1992-04-01

    A picture archiving and communication system (PACS) infrastructure is the necessary framework to integrate distributed and heterogeneous imaging systems, provide intelligent data-base management of all radiology-related information, arrange an efficient means of viewing, analyzing, and documenting study results, and furnish a mechanism for effectively communicating study results to the referring physician. The PACS infrastructure consists of a basic skeleton of hardware components integrated by standardized, flexible software subsystems. This review describes these concepts and basic building blocks drawn from our original investigation, past experience, and the current clinical system in our radiology department.

  14. Application Research on Space Laser Communication in Bistatic Radar System

    Institute of Scientific and Technical Information of China (English)

    李晓萍; 韩绍坤; 郝小宁

    2003-01-01

    There exist three synchronizing problems in the bistatic radar system that some signals of the radar receiver must be synchronized with those of the radar transmitter. Several methods realizing data transmission, which are used to complete the synchronization existing in the bistatic radar system, are described. Then a new idea is brought forward that employs space laser communication in the bistatic radar system to realize its data transmission. The theoretic analysis of the idea's usability and its merits are discussed in details. Finally the latest development of space laser communication is introduced, and the utility of the idea is pointed out further.

  15. Inter Processor Communication for Fault Diagnosis in Multiprocessor Systems

    Directory of Open Access Journals (Sweden)

    C. D. Malleswar

    1994-04-01

    Full Text Available In the preseJlt paper a simple technique is proposed for fault diagnosis for multiprocessor and multiple system environments, wherein all microprocessors in the system are used in part to check the health of their neighbouring processors. It involves building simple fail-safe serial communication links between processors. Processors communicate with each other over these links and each processor is made to go through certain sequences of actions intended for diagnosis, under the observation of another processor .With limited overheads, fault detection can be done by this method. Also outlined are some of the popular techniques used for health check of processor-based systems.

  16. Security Communication Model of Wireless Trade System

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wen-kai; ZHANG Si-yu

    2005-01-01

    This paper proposes a C/S system model for K Java and PDA named Net-Wireless. It is a discussion and proposal on information security and solutions for K-Java handsets and PDAs in wireless network. It also explains the scheme which between client security module and server security module. Also, We have developed a Security Server and a K-Java encryption module for e-commerce system and other trade systems.

  17. Combining Chemical Information Literacy, Communication Skills, Career Preparation, Ethics, and Peer Review in a Team-Taught Chemistry Course

    Science.gov (United States)

    Jones, Mary Lou Baker; Seybold, Paul G.

    2016-01-01

    The widely acknowledged need to include chemical information competencies and communication skills in the undergraduate chemistry curriculum can be accommodated in a variety of ways. We describe a team-taught, semester-length course at Wright State University which combines chemical information literacy, written and oral communication skills,…

  18. Combining Chemical Information Literacy, Communication Skills, Career Preparation, Ethics, and Peer Review in a Team-Taught Chemistry Course

    Science.gov (United States)

    Jones, Mary Lou Baker; Seybold, Paul G.

    2016-01-01

    The widely acknowledged need to include chemical information competencies and communication skills in the undergraduate chemistry curriculum can be accommodated in a variety of ways. We describe a team-taught, semester-length course at Wright State University which combines chemical information literacy, written and oral communication skills,…

  19. A Novel Keyless Entry System Using Visible Light Communication

    Directory of Open Access Journals (Sweden)

    Kuniyoshi Okuda

    2014-10-01

    Full Text Available A major conventional car key is the mechanical key. When users inserted the key into a cylinder mechanical key and turn, users can unlock. The mechanical key may be able to be worn away for physical contact. And it may be impossible to use. Further the mechanical key may be damaged or destroyed by mischief. So a keyless entry system has been developed. The keyless entry system locks and unlocks using the infrared ray and radio waves communication. The keyless entry system does not require physical contacts. Therefore, the possibilities of damage due to mischief and be worn away are fell. However, the transmission ranges of infrared ray and radio waves communication are not clear. Submitting data might be tapped to the malicious people. If the information is tapped, then you have theft of the car and the risk of car break. We propose a keyless entry system using visible light communication in order to solve this problem. Visible light communication transmits signal using blinking light. Thus the transmission range is clear. The user can transmit the information only to the aimed place. Therefore, the usability is improved. We measure the durations of "take out the remote control", "put the aim" and "takes to unlock key" in order to evaluate the usability in the experiment. We also compared with the infrared ray communication and examined the superiority. Usability is improved in the experimental results, and usability is better than conventional keyless entry system.

  20. Synchronization of the chaotic secure communication system with output state delay

    Energy Technology Data Exchange (ETDEWEB)

    Changchien, S.-K. [Department of Electrical Engineering, Chienkuo Technology University, Changhua 500, Taiwan (China)], E-mail: ccsk@ctu.edu.tw; Huang, C.-K.; Nien, H.-H.; Shieh, H.-W. [Department of Electrical Engineering, Chienkuo Technology University, Changhua 500, Taiwan (China)

    2009-02-28

    In this paper, we utilize a proper Lyapunov function and Lyapunov theorem, combined with LMIs method, in order to design a controller L, which ensures the synchronization between the transmission and the reception ends of the chaotic secure communication system with time-delay of output state. Meanwhile, for the purpose of increasing communication security, we encrypt and decrypt the original to-be-transmitted message with the techniques of n-shift cipher and public key. The result of simulation shows that the proposed method is able to synchronize the transmission and the reception ends of the system, and moreover, to recover the original message at the reception end. Therefore, the method proposed in this paper is effective and feasible to apply in the chaotic secure communication system.

  1. BANDWIDTH OF QUANTUM OPTICAL COMMUNICATION SYSTEM

    Directory of Open Access Journals (Sweden)

    I. R. Gulakov

    2012-01-01

    Full Text Available Impact of registered optical radiation intensity, overvoltage, dimensions of photosensitive surface, structure of p-n junction and avalanche photodetectors dead time operating in the photon counting mode on quantum optical system capacity has been carried out in this investigation. As a result, the quantum optical system maximum capacity of 81 kbit/s has been obtained.

  2. Low-Power Reflective Optical Communication System for Pico- and Nano-Satellites

    Science.gov (United States)

    Sinn, A.; Riel, T.; Deisl, F.; Saathof, R.; Schitter, G.

    2016-09-01

    Pico- and nano-satellites (PNS) are promising options for cost-effective and rapid deployable satellite systems. Due to their small size, the available power and therefore the transmittable data volume is limited. This paper proposes optical communication by means of reflected laser light using a modulating retro-reflector (MRR) for energy efficient optical communication with PNS. No laser source or beam steering assembly is necessary at the satellite, thus allowing a weight and energy efficient communication interface. Existing ground stations (GS) as used for satellite laser ranging (SLR) provide all equipment required for this system. By providing a link budget for communication to PNS in LEOs feasibility is investigated. It is shown that an affordable GS based on small telescopes with diameters below 0.3m in combination with commercial mounts enables the targeted application. A detailed analysis of LCD based MRRs is shown, denoting cost-efficient modulators for reflective optical communication. A data-rate of 2.5kbps at an input power of less than 80 mW is shown in a laboratory setup. Using a high performance sampling circuit and a laser power of only 1mW, a bit error ratio (BER) of below 10e-3 is achieved, successfully demonstrating reflective optical communication as an alternative to current RF based systems.

  3. Kansas Communication and Instruction System through Fiber-Optic Transmission.

    Science.gov (United States)

    Kansas State Dept. of Education, Topeka.

    Schools and communities will restructure as they move into the next decade. The success of this restructuring will be dependent upon access to and sharing of quality teaching and information through an expanded communication system. One of the major two-way interactive technologies is the fiber-optic cable: a delivery system that will provide…

  4. Computer-Aided Communication Satellite System Analysis and Optimization.

    Science.gov (United States)

    Stagl, Thomas W.; And Others

    Various published computer programs for fixed/broadcast communication satellite system synthesis and optimization are discussed. The rationale for selecting General Dynamics/Convair's Satellite Telecommunication Analysis and Modeling Program (STAMP) in modified form to aid in the system costing and sensitivity analysis work in the Program on…

  5. An Embedded System Dedicated to Intervehicle Communication Applications

    Directory of Open Access Journals (Sweden)

    Zhou Haiying

    2010-01-01

    Full Text Available To overcome system latency and network delay is essential for intervehicle communication (IVC applications such as hazard alarming and cooperative driving. This paper proposes a low-cost embedded software system dedicated to such applications. It consists of two basic component layers: an operating system, named HEROS (hybrid event-driven and real-time multitasking operating system, and a communication protocol, named CIVIC (Communication Inter Véhicule Intelligente et Coopérative. HEROS is originally designed for wireless sensor networks (WSNs. It contains a component-based resource-aware kernel and a low-latency tuple-based communication system. Moreover, it provides a configurable event-driven and/or real-time multitasking mechanism for various embedded applications. The CIVIC is an autoconfiguration cooperative IVC protocol. It merges proactive and reactive approaches to speed up and optimize location-based routing discovery with high-mobility nodes. Currently, this embedded system has been implemented and tested. The experiment results show that the new embedded system has low system latency and network delay under the principle of small resource consumption.

  6. Systems and methods for free space optical communication

    Science.gov (United States)

    Harper, Warren W [Benton City, WA; Aker, Pamela M [Richland, WA; Pratt, Richard M [Richland, WA

    2011-05-10

    Free space optical communication methods and systems, according to various aspects are described. The methods and systems are characterized by transmission of data through free space with a digitized optical signal acquired using wavelength modulation, and by discrimination between bit states in the digitized optical signal using a spectroscopic absorption feature of a chemical substance.

  7. 76 FR 62321 - Airworthiness Directives; Aviation Communication & Surveillance Systems (ACSS) Traffic Alert and...

    Science.gov (United States)

    2011-10-07

    ... Communication & Surveillance Systems (ACSS) Traffic Alert and Collision Avoidance System (TCAS) Units AGENCY... certain Aviation Communication & Surveillance Systems (ACSS) traffic alert and collision avoidance system...) traffic alert and collision avoidance system (TCAS) units with part numbers identified in ACSS...

  8. Combined chemical and structural signals of biomaterials synergistically activate cell-cell communications for improving tissue regeneration.

    Science.gov (United States)

    Xu, Yachen; Peng, Jinliang; Dong, Xin; Xu, Yuhong; Li, Haiyan; Chang, Jiang

    2017-06-01

    Biomaterials are only used as carriers of cells in the conventional tissue engineering. Considering the multi-cell environment and active cell-biomaterial interactions in tissue regeneration process, in this study, structural signals of aligned electrospun nanofibers and chemical signals of bioglass (BG) ionic products in cell culture medium are simultaneously applied to activate fibroblast-endothelial co-cultured cells in order to obtain an improved skin tissue engineering construct. Results demonstrate that the combined biomaterial signals synergistically activate fibroblast-endothelial co-culture skin tissue engineering constructs through promotion of paracrine effects and stimulation of gap junctional communication between cells, which results in enhanced vascularization and extracellular matrix protein synthesis in the constructs. Structural signals of aligned electrospun nanofibers play an important role in stimulating both of paracrine and gap junctional communication while chemical signals of BG ionic products mainly enhance paracrine effects. In vivo experiments reveal that the activated skin tissue engineering constructs significantly enhance wound healing as compared to control. This study indicates the advantages of synergistic effects between different bioactive signals of biomaterials can be taken to activate communication between different types of cells for obtaining tissue engineering constructs with improved functions. Tissue engineering can regenerate or replace tissue or organs through combining cells, biomaterials and growth factors. Normally, for repairing a specific tissue, only one type of cells, one kind of biomaterials, and specific growth factors are used to support cell growth. In this study, we proposed a novel tissue engineering approach by simply using co-cultured cells and combined biomaterial signals. Using a skin tissue engineering model, we successfully proved that the combined biomaterial signals such as surface nanostructures

  9. Combined solar-thermal/photovoltaic system

    Energy Technology Data Exchange (ETDEWEB)

    Krauter, Stefan; Schroer, Sandra [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Lab. Fotovoltaico]. E-mail: krauter@coe.ufrj.br; Salhi, Mohammed J. [Solon AG fuer Solartechnik, Berlin (Germany)]. E-mail: solonag@solonag.com; Hanitsch, Rolf [Berlin Inst. of Tech. (Germany). Inst. for Electrical Energy Systems]. E-mail: rolf.hanitsch@iee.TU-Berlin.de

    2000-07-01

    Combination of photovoltaic (PV) and solar thermal elements allows to generate electricity and heat at reduced costs. The substitution of conventional facade elements (includes the thermal insulation of building) increases the benefit. Conventional photovoltaic are built as curtain facades in front of thermally insulated buildings with air ducts in between. This causes additional costs for support structures and installation, while heat dissipation from the solar cells is often not optimal. Measurements carried out are facing both concerns: integration of a thermal insulation layer (which meets the latest german heat preserving regulation WSW 95) into the P V facade allows a reduction of cell operating temperature of 18 K, resulting in a 8 % increase in electrical output at an air velocity of about 2 m/s. Cell temperatures increase by 20.7 K at thermal insulating P V facade elements (TIPVE) without cooling, which causes a 9.3 % loss of electrical yield, but installation costs can be reduced by 20 % (all related to a conventional P V curtain plus a heat insulating facade at a building). HYTIPVE, a hybrid thermal insulating P V facade element combined with a water cooling system, which could also serve for hot water heating, lowers operating cells temperature by 20 K and increases electrical yield by 9 % (referred to conventional curtain P V facades). Further economic investigations of each HYTIPVE including its operational costs and substitution effect related to the electrical and thermal yield are on the way. (author)

  10. Unmanned Aircraft System Control and ATC Communications Bandwidth Requirements

    Science.gov (United States)

    Henriksen, Steve

    2008-01-01

    There are significant activities taking place to establish the procedures and requirements for safe and routine operation of unmanned aircraft systems (UAS) in the National Airspace System (NAS). Among the barriers to overcome in achieving this goal is the lack of sufficient frequency spectrum necessary for the UAS control and air traffic control (ATC) communications links. This shortcoming is compounded by the fact that the UAS control communications links will likely be required to operate in protected frequency spectrum, just as ATC communications links are, because they relate to "safety and regularity of flight." To support future International Telecommunications Union (ITU) World Radio Conference (WRC) agenda items concerning new frequency allocations for UAS communications links, and to augment the Future Communications Study (FCS) Technology Evaluation Group efforts, NASA Glenn Research Center has sponsored a task to estimate the UAS control and ATC communications bandwidth requirements for safe, reliable, and routine operation of UAS in the NAS. This report describes the process and results of that task. The study focused on long-term bandwidth requirements for UAS approximately through 2030.

  11. The Device Centric Communication System for 5G Networks

    Science.gov (United States)

    Biswash, S. K.; Jayakody, D. N. K.

    2017-01-01

    The Fifth Generation Communication (5G) networks have several functional features such as: Massive Multiple Input and Multiple Output (MIMO), Device centric data and voice support, Smarter-device communications, etc. The objective for 5G networks is to gain the 1000x more throughput, 10x spectral efficiency, 100 x more energy efficiency than existing technologies. The 5G system will provide the balance between the Quality of Experience (QoE) and the Quality of Service (QoS), without compromising the user benefit. The data rate has been the key metric for wireless QoS; QoE deals with the delay and throughput. In order to realize a balance between the QoS and QoE, we propose a cellular Device centric communication methodology for the overlapping network coverage area in the 5G communication system. The multiple beacon signals mobile tower refers to an overlapping network area, and a user must be forwarded to the next location area. To resolve this issue, we suggest the user centric methodology (without Base Station interface) to handover the device in the next area, until the users finalize the communication. The proposed method will reduce the signalling cost and overheads for the communication.

  12. The transmission link of CAPS navigation and communication system

    Institute of Scientific and Technical Information of China (English)

    CUI JunXia; SHI HuLi; CHEN JiBin; PEI Jun

    2009-01-01

    The Chinese Area Positioning System (CAPS) is based on communication satellites with integrated oapability,whioh is different from the Global Positioning System (GPS),the International Maritime Satellite Organization (Inmarsat) and so on.CAPS works at G-band,and its navigation information ie not directly generated from the satellite,but from the master control station on the ground and transmitted to users via the satellite.The slightly inclined geostationary-satellite orbit (SIGSO) satellites are adopted in CAPS.All of these increase the difficulty in the design of the system and terminals.In this paper,the authors study the CAPS oonfiguration parameters of the navigation master control station,information transmission capability,and the selection of the antenna aperture of the communication oenter station,as well as the impact of satellite parameters on the whole communication system from the perspective of the transmission link budget.The conclusion of availability of the GAPS navigation system is achieved.The results show that the GAPS inbound communication system forms a new low-data-rate satellite communicaUon system,which can accommodate mass communication termihale with the transmission rate of no more than 1 kbps for every terminal.The communication center station should be configured with a large-aperture antenna (about 10--15 m); spread spectrum communication technology should be used with the spreading gain as high as about 40 dB; reduction of the satellite transponder gain attenuation is beneficial to improving the signal-to-noise ratio of the system,with the attenuation value of 0 or 2 dB as the best choice.The fact that the GAPS navigation system has been checked and aooepted by the experts and the operation is stable till now larifies the rationality of the analysis results.The fact that a variety of experiments and applications of the satellite communication system designed according to the findings in this paper have been successfully carried out

  13. The Peace System – As a Self-Referential Communication System

    DEFF Research Database (Denmark)

    Harste, Gorm

    2013-01-01

    Peace communication as diplomatic communication is an often neglected phenomenon in social and political theory that concerns problems of international order, justice and peace. Political philosophy seldom embarks on the theme with more than a few comments. Yet, throughout history, diplomacy has ...... of communication, and to get some added value in this respect, Niklas Luhmann’s theory of self-referential communication systems has been applied....

  14. Advanced information processing system: Authentication protocols for network communication

    Science.gov (United States)

    Harper, Richard E.; Adams, Stuart J.; Babikyan, Carol A.; Butler, Bryan P.; Clark, Anne L.; Lala, Jaynarayan H.

    1994-01-01

    In safety critical I/O and intercomputer communication networks, reliable message transmission is an important concern. Difficulties of communication and fault identification in networks arise primarily because the sender of a transmission cannot be identified with certainty, an intermediate node can corrupt a message without certainty of detection, and a babbling node cannot be identified and silenced without lengthy diagnosis and reconfiguration . Authentication protocols use digital signature techniques to verify the authenticity of messages with high probability. Such protocols appear to provide an efficient solution to many of these problems. The objective of this program is to develop, demonstrate, and evaluate intercomputer communication architectures which employ authentication. As a context for the evaluation, the authentication protocol-based communication concept was demonstrated under this program by hosting a real-time flight critical guidance, navigation and control algorithm on a distributed, heterogeneous, mixed redundancy system of workstations and embedded fault-tolerant computers.

  15. Communication issues in parallel systems with optical interconnections

    Science.gov (United States)

    Berthome, Pascal; Ferreira, A.

    1995-02-01

    In classical massively parallel computers, the complexity of the interconnection networks is much higher than the complexity of the processing elements themselves. Optical interconnections may provide a way to reconsider very large parallel architectures. We compare some optically interconnected parallel multicomputer models with regard to their communication capabilities. We first establish a distinction of such systems, based on the independence of the communication elements embedded in the processors (transmitters and receivers). Then, motivated by the fact that in multicomputers some communication operations have to be very efficiently performed, we study two fundamental communication problems, namely, one-to-all and all-to-all, under the hypothesis of bounded fanout. Our results take also into account a bounded number of available wavelengths.

  16. Patterns of Programmers' Use of Computer-Mediated Communications Systems

    Directory of Open Access Journals (Sweden)

    Chatpong Tangmanee

    2003-11-01

    Full Text Available Communication behavior of programmers plays an essential role in success of software development. Computer-mediated communication (CMC system, such as e-mail, or the World Wide Web (WWW, have substantial implications for coordinating work of programmers. Yet, no studies have dealt systematically with CMC behaviors of programmers. Drawing upon theories in organizational studies, information science, computer-mediated communication and software engineering, this research examines what programmers accomplish through CMC systems. Data were gathered from survey questionnaires mailed to 730 programmers, who are members of the Association of Computing Machinery (ACM and are involved in a variety of programming work. Based on factor analysis, the study found that programmers use CMC systems (1 to achieve progress in work-related tasks (i.e., task-related purposes, (2 to satisfy their social and emotional needs (i.e., socio-emotional purposes, and (3 to explore for information (i.e., exploring purposes. The findings of this research extend an insight into important patterns for which programmers use CMC systems. This insight has advanced theories of computer-mediated communication in the context of computer programmers. Also, practitioners, especially in software development, may use the results as guidelines in fostering a firm’s feasible network policy that fits with what their programming staff accomplish through computer-mediated communication.

  17. Zipf's law emerges asymptotically during phase transitions in communicative systems

    CERN Document Server

    Khomtchouk, Bohdan B

    2016-01-01

    Zipf's law predicts a power-law relationship between word rank and frequency in language communication systems, and is widely reported in texts yet remains enigmatic as to its origins. Computer simulations have shown that language communication systems emerge at an abrupt phase transition in the fidelity of mappings between symbols and objects. Since the phase transition approximates the Heaviside or step function, we show that Zipfian scaling emerges asymptotically at high rank based on the Laplace transform which yields $(1/r)(1-e^{-r})$, where $r$ denotes rank. We thereby demonstrate that Zipf's law gradually emerges from the moment of phase transition in communicative systems. We show that this power-law scaling behavior explains the emergence of natural languages at phase transitions. We find that the emergence of Zipf's law during language communication suggests that the use of rare words in a lexicon (i.e., high $r$) is critical for the construction of an effective communicative system at the phase tra...

  18. A Radio Communication System for Neuronal Signals

    Institute of Scientific and Technical Information of China (English)

    Wang Min; Yang Maoquan; Wang Xiaojun; Guang Kui; Zhang Xiao

    2012-01-01

    To collect neuronal activity data from awake, freely behaving animals, we developed miniature telemetry recording system. The integrated system consists of four major components: l) Microelectrodes and micro-driver assembly, 2) analog front end (AFE), 3) programmable system on chip (PSoC), and 4) ra- dio transceiver and the LabVIEW were used as a platform for the graphic user interface. The result showed the system was able to record and analyze neuronal recordings in freely moving animals and lasted continuously for a time period of a week or more. This is very useful for the study of the interdisciplinary research of neu- roscience and information engineering techniques. The circuits and architecture of the devices can be adapted for neurobiology and research with other small animals.

  19. Communication systems vital to Colombian pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Serrato, E. [Ecopetrol, Bogota (Colombia); Mailloux, R. [Bristol Babcock Inc., Watertown, CT (United States)

    1997-02-01

    Construction of the Centro Oriente Gas Pipeline represents a major step in Colombia`s goal to strengthen the emerging natural gas business. With construction beginning in 1995, the Centro Oriente is scheduled to begin operation early this year transporting 150 MMcf/d. The 779-kilometer (484-mile) pipeline ranging in diameter from 22-inch to 12-inches, provides the central transportation link between major gas suppliers in both the northern and western regions of Colombia and new markets throughout their immediate regions as well as in the central and eastern regions. TransCanada, operating company for the Centro Oriente pipeline, will develop and manage the support organizations required to operate and maintain the system. The central control system for the CPC is the Gas SCADA system, ADACS, provided by Bristol Babcock Inc. (BBI). This control system provides the data acquisition and control capabilities necessary to operate the entire pipeline safely and efficiently from Burcaramanga.

  20. Sensory evolution of hearing in tettigoniids with differing communication systems.

    Science.gov (United States)

    Strauß, J; Lehmann, A W; Lehmann, G U C

    2014-01-01

    In Tettigoniidae (Orthoptera: Ensifera), hearing organs are essential in mate detection. Male tettigoniids usually produce calling songs by tegminal stridulation, whereas females approach the males phonotactically. This unidirectional communication system is the most common one among tettigoniids. In several tettigoniid lineages, females have evolved acoustic replies to the male calling song which constitutes a bidirectional communication system. The genus Poecilimon (Tettigoniidae: Phaneropterinae) is of special interest because the ancestral state of bidirectional communication, with calling males and responding females, has been reversed repeatedly to unidirectional communication. Acoustic communication is mediated by hearing organs that are adapted to the conspecific signals. Therefore, we analyse the auditory system in the Tettigoniidae genus Poecilimon for functional adaptations in three characteristics: (i) dimension of sound-receiving structures (tympanum and acoustic spiracle), (ii) number of auditory sensilla and (iii) hearing sensitivity. Profound differences in the auditory system correlate with uni- or bidirectional communication. Among the sound-receiving structures, the tympana scale with body size, whereas the acoustic spiracle, the major sound input structure, was drastically reduced in unidirectional communicating species. In the unidirectional P. ampliatus group, auditory sensilla are severely reduced in numbers, but not in the unidirectional P. propinquus group. Within the P. ampliatus group, the number of auditory sensilla is further reduced in P. intermedius which lost acoustic signalling due to parthenogenesis. The auditory sensitivity correlated with the size of the acoustic spiracle, as hearing sensitivity was better with larger spiracles, especially in the ultrasonic range. Our results show a significant reduction in auditory structures, shaped by the differing sex roles during mate detection.

  1. Ultra-Reliable Communication in 5G Wireless Systems

    DEFF Research Database (Denmark)

    Popovski, Petar

    2014-01-01

    —Wireless 5G systems will not only be “4G, but faster”. One of the novel features discussed in relation to 5G is Ultra-Reliable Communication (URC), an operation mode not present in today’s wireless systems. URC refers to provision of certain level of communication service almost 100 % of the time....... Example URC applications include reliable cloud connectivity, critical connections for industrial automation and reliable wireless coordination among vehicles. This paper puts forward a systematic view on URC in 5G wireless systems. It starts by analyzing the fundamental mechanisms that constitute......-term URC (URC-S). The second dimension is represented by the type of reliability impairment that can affect the communication reliability in a given scenario. The main objective of this paper is to create the context for defining and solving the new engineering problems posed by URC in 5G....

  2. Potential markets for a satellite-based mobile communications system

    Science.gov (United States)

    Jamieson, W. M.; Peet, C. S.; Bengston, R. J.

    1976-01-01

    The objective of the study was to define the market needs for improved land mobile communications systems. Within the context of this objective, the following goals were set: (1) characterize the present mobile communications industry; (2) determine the market for an improved system for mobile communications; and (3) define the system requirements as seen from the potential customer's viewpoint. The scope of the study was defined by the following parameters: (1) markets were confined to U.S. and Canada; (2) range of operation generally exceeded 20 miles, but this was not restrictive; (3) the classes of potential users considered included all private sector users, and non-military public sector users; (4) the time span examined was 1975 to 1985; and (5) highly localized users were generally excluded - e.g., taxicabs, and local paging.

  3. A new method for chaos control in communication systems

    Energy Technology Data Exchange (ETDEWEB)

    Lin, S.-L. [Department of Mechanical Engineering, National Central University, No. 300, Jhongda Rd., Jhongli City, Taoyuan County 32001, Taiwan (China); Tung, P.-C. [Department of Mechanical Engineering, National Central University, No. 300, Jhongda Rd., Jhongli City, Taoyuan County 32001, Taiwan (China)], E-mail: t331166@ncu.edu.tw

    2009-12-15

    With the increasing needs of global communication, the improvement of secure communication is of vital importance. This study proposes a new scheme for establishing secure communication systems. The new scheme separates white Gaussian noises from the chaotic signals with modified Independent Component Analysis (ICA) and then controls each chaotic signal. This scheme is able to deal with white Gaussian noises in the natural world. However, the signals separated by traditional ICA shows opposite phase and unequal amplitude, making chaos control impossible. Our study proposed a modified ICA, which can calculate accurately the phase and amplitude and ensure control of the chaotic systems. The result indicates that our proposed system can successfully separate white Gaussian noise and stabilize all the chaotic signals.

  4. Channel cooperation for anti-occlusion visible light communication systems

    Science.gov (United States)

    Liu, Yuxin; Huang, Zhitong; Li, Wei; Ji, Yuefeng

    2016-10-01

    The need to exchange data wirelessly has increased as the growth of the number of mobile devices. Visible light communication (VLC) is a promising technology to alleviate the growing traffic problem. However, the occlusion problem is a difficulty in VLC system. In order to solve the problem, an anti-occlusion VLC system has been proposed in this article. In this VLC system, we propose the channel cooperative selection mechanism, which is based on the best-response dynamics and best response strategies of the game theory. This mechanism uses bit error ratio (BER) as the utility function to optimize system performance. In addition, the system provides three candidate communication channels, including direct channel, indirect channel, and mixed channel, to active users who will select the optimal communication channel. Moreover, the anti-occlusion VLC system has many application scenarios, such as the office, which has practical significance. For verifying the validity of the proposed mechanism, we accomplish the simulation results in terms of BER and throughput in different communication cases. It is demonstrated that the proposed channel cooperative selection mechanism in VLC systems offers superior performance in environment of obstructions.

  5. Western Area Power Administration. Combined power system financial statements

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-26

    This report presents the results of the independent certified public accountants` audit of the Western Area Power Administration`s combined power system statements of assets, Federal investment and liabilities, and the related combined statements of revenues, expenses and accumulated net revenues, and cash flows. The auditors` report on Westerns internal control structure disclosed three new reportable conditions concerning the lack of: (1) a reconciliation of stores inventory from subsidiary ledgers to summary financial information, (2) communication of interest during construction and related adjustments to interest on Federal investment, and (3) a system to prevent and detect power billing errors. None of the conditions were considered to be material weaknesses. Western provided concurrence and corrective action plans. The auditors` report on Western`s compliance with laws and regulations also disclosed two new instances of noncompliance. Western failed to calculate nonreimbursable expenses in accordance with the Grand Canyon Protection Act and had an unexplained difference in gross Federal investment balances used to calculate interest on Federal investment. Western provided concurrence and corrective action plans for the instances.

  6. Free-space optical communications using orbital-angular-momentum multiplexing combined with MIMO-based spatial multiplexing.

    Science.gov (United States)

    Ren, Yongxiong; Wang, Zhe; Xie, Guodong; Li, Long; Cao, Yinwen; Liu, Cong; Liao, Peicheng; Yan, Yan; Ahmed, Nisar; Zhao, Zhe; Willner, Asher; Ashrafi, Nima; Ashrafi, Solyman; Linquist, Roger D; Bock, Robert; Tur, Moshe; Molisch, Andreas F; Willner, Alan E

    2015-09-15

    We explore the potential of combining the advantages of multiple-input multiple-output (MIMO)-based spatial multiplexing with those of orbital angular momentum (OAM) multiplexing to increase the capacity of free-space optical (FSO) communications. We experimentally demonstrate an 80 Gbit/s FSO system with a 2×2 aperture architecture, in which each transmitter aperture contains two multiplexed data-carrying OAM modes. Inter-channel crosstalk effects are minimized by the OAM beams' inherent orthogonality and by the use of 4×4 MIMO signal processing. Our experimental results show that the bit-error rates can reach below the forward error correction limit of 3.8×10(-3) and the power penalties are less than 3.6 dB for all channels after MIMO processing. This indicates that OAM and MIMO-based spatial multiplexing could be simultaneously utilized, thereby providing the potential to enhance system performance.

  7. Applying Model Based Systems Engineering to NASA's Space Communications Networks

    Science.gov (United States)

    Bhasin, Kul; Barnes, Patrick; Reinert, Jessica; Golden, Bert

    2013-01-01

    System engineering practices for complex systems and networks now require that requirement, architecture, and concept of operations product development teams, simultaneously harmonize their activities to provide timely, useful and cost-effective products. When dealing with complex systems of systems, traditional systems engineering methodology quickly falls short of achieving project objectives. This approach is encumbered by the use of a number of disparate hardware and software tools, spreadsheets and documents to grasp the concept of the network design and operation. In case of NASA's space communication networks, since the networks are geographically distributed, and so are its subject matter experts, the team is challenged to create a common language and tools to produce its products. Using Model Based Systems Engineering methods and tools allows for a unified representation of the system in a model that enables a highly related level of detail. To date, Program System Engineering (PSE) team has been able to model each network from their top-level operational activities and system functions down to the atomic level through relational modeling decomposition. These models allow for a better understanding of the relationships between NASA's stakeholders, internal organizations, and impacts to all related entities due to integration and sustainment of existing systems. Understanding the existing systems is essential to accurate and detailed study of integration options being considered. In this paper, we identify the challenges the PSE team faced in its quest to unify complex legacy space communications networks and their operational processes. We describe the initial approaches undertaken and the evolution toward model based system engineering applied to produce Space Communication and Navigation (SCaN) PSE products. We will demonstrate the practice of Model Based System Engineering applied to integrating space communication networks and the summary of its

  8. Intelligent fault isolation and diagnosis for communication satellite systems

    Science.gov (United States)

    Tallo, Donald P.; Durkin, John; Petrik, Edward J.

    1992-01-01

    Discussed here is a prototype diagnosis expert system to provide the Advanced Communication Technology Satellite (ACTS) System with autonomous diagnosis capability. The system, the Fault Isolation and Diagnosis EXpert (FIDEX) system, is a frame-based system that uses hierarchical structures to represent such items as the satellite's subsystems, components, sensors, and fault states. This overall frame architecture integrates the hierarchical structures into a lattice that provides a flexible representation scheme and facilitates system maintenance. FIDEX uses an inexact reasoning technique based on the incrementally acquired evidence approach developed by Shortliffe. The system is designed with a primitive learning ability through which it maintains a record of past diagnosis studies.

  9. Propagation handbook for wireless communication system design

    CERN Document Server

    Crane, Robert K

    2003-01-01

    PROPAGATION PHENOMENA AFFECTING WIRELESS SYSTEMS Types of SystemsDesign Criteria Antenna Considerations Propagation Effects Propagation Models Model Verification Statistics and RiskList of Symbols ReferencesPROPAGATION FUNDAMENTALSMaxwell's EquationsPlane Waves Spherical Waves Reflection and Refraction Geometrical OpticsRay TracingScalar Diffraction Theory Geometrical Theory of Diffraction List of Symbols ReferencesABSORPTION Molecular Absorption Absorption on a Slant Path ACTS Statistics List of Symbols ReferencesREFRACTION Ray BendingPath Delay ScintillationList of Symbols ReferencesATTENUAT

  10. Low level communication management for e-health systems

    Science.gov (United States)

    Riva, Guillermo; Zerbini, Carlos; Voos, Javier; Centeno, Carlos; González, Eduardo

    2011-12-01

    The heterogeneity of e-health systems encourages the use of standards such as Health Level 7 (HL7v3) to ensure interoperability. Many actual implementations address this problem by unoptimized high level programming of top-range portable computing platforms. However, this approach could pose excessive demands on battery-powered mid-range terminals. In this work, we propose low-level support for portable HL7v3-compatible embedded systems in order to better exploit their limited processing and communications capabilities. In particular, we present our experience in mobile communication management through two different approaches, which proves the feasibility of this proposal.

  11. Critical components in 0.14 THz communication systems

    CERN Document Server

    Shan, Guangcun; Zhu, Haoshen; Shek, Chan-Hung

    2012-01-01

    In the super-heterodyne terahertz communication system, the proper design of the critical components like mixers and filters are of great importance for enhancing its performance. In this work, some issues on our newly developed system setup design for 0.14 THz wireless communications and the key components subharmonic mixer (SHM) based on Schottky diode, as well as silicon micromachined bandpass rectangular waveguide filters are presented. According to ADS simulation, the optimum conversion loss of the 140 GHz SHM is 26 dB. And the silicon-micromachined rectangular waveguide filters have been fabricated and the measured lowset insertion losses are lower than 0.5 dB.

  12. The Application of Save Functions of SDL in Communication Systems

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The communication system is composed of more than one processes, which realize the functions of the system together. In most of the distributed environments, the message is the way that they are communicated a with each other. But they can not be guaranteed to arrive at the right time. In this paper, we discuss the save functions in the Specification and Description Language ( SDL) language. With these functions, a new way of transferring message can be realized reliably and efficiently. Finally, we give the simulation result according to the tools--SDT.

  13. Exploiting the natural redundancy of chaotic signals in communication systems

    Science.gov (United States)

    Marino; Rosa; Grebogi

    2000-09-18

    Chaotic signals can be used as carriers of information in communication systems. In this work we describe a simple encoding method that allows one to map any desired bit sequence into a chaotic waveform. The redundancy of the resulting information carrying signal enables us to devise a novel signal reconstruction technique that is able to recover relatively large parts of the chaotic signal starting from just a few samples of it. We show that this technique allows one to increase both the transmission reliability and the transmission rate of a communication system even in the presence of noise.

  14. Design and characteristics of a multiband communication satellite antenna system

    Science.gov (United States)

    Ueno, Kenji; Itanami, Takao; Kumazawa, Hiroyuki; Ohtomo, Isao

    1995-04-01

    Feasibility studies on a multiband communication satellite antenna system and the key technologies involved in devising this system are described. The proposed multiband communication satellite utilizes four frequency bands: Ka (30/20 GHz), Ku (14/12 GHz), C (6/4 GHz), and S (2.6/2.5 GHz). It has six beam configurations, three multibeam and three shaped-beam. The following key technologies are presented: (1) a low-loss frequency selective subreflector (FSR) for compact feeds, (2) a low-loss and broadband frequency selective surface (FSS), and (3) a highly accurate and reliable mesh reflector.

  15. Simulation of communication line for down hole telemetry systems

    Science.gov (United States)

    Ishchenko, A. V.; Belov, M. D.; Khokhlov, K. O.; Tcherepanov, A. N.; Naronov, A. S.

    2016-09-01

    The results of simulation of equivalent circuit of transmission line of down hole telemetry system has been presented. The paper shows the possible solution of communication system by a power-line communication technique for downhole monitoring. On the base of simulation results of equivalent circuit of presented model of transmission line the binary frequency-shift keying (BFSK) method of information transmission is proposed. The simulation of the temperature changing and disturbance appearance has been made. The influence of them on the signal parameters are presented and discussed.

  16. Influence of beam wander on bit-error rate in a ground-to-satellite laser uplink communication system.

    Science.gov (United States)

    Ma, Jing; Jiang, Yijun; Tan, Liying; Yu, Siyuan; Du, Wenhe

    2008-11-15

    Based on weak fluctuation theory and the beam-wander model, the bit-error rate of a ground-to-satellite laser uplink communication system is analyzed, in comparison with the condition in which beam wander is not taken into account. Considering the combined effect of scintillation and beam wander, optimum divergence angle and transmitter beam radius for a communication system are researched. Numerical results show that both of them increase with the increment of total link margin and transmitted wavelength. This work can benefit the ground-to-satellite laser uplink communication system design.

  17. A Study of Communication Processor Systems

    Science.gov (United States)

    1979-12-01

    switch and/or packet switch users. The test node simulator includes the following: 1. test node simulator software package: a. microscopic simulation...1974 (37] J. P. Coudreuse et al., "ElO System: Tim Division Tandem Exchanges," Commutation et Electronique , June 1975. 179 MISSION Of Rowe Air

  18. Energy Systems Integration: Demonstrating Distributed Resource Communications

    Energy Technology Data Exchange (ETDEWEB)

    2017-01-01

    Overview fact sheet about the Electric Power Research Institute (EPRI) and Schneider Electric Integrated Network Testbed for Energy Grid Research and Technology Experimentation (INTEGRATE) project at the Energy Systems Integration Facility. INTEGRATE is part of the U.S. Department of Energy's Grid Modernization Initiative.

  19. Smart Systems Integration for Autonomous Wireless Communications

    NARCIS (Netherlands)

    Danesh, M.

    2012-01-01

    Integration of sensors and wireless transceivers for system networking aims at emerging applications that are highly integrated, self-powered, and low cost, relying on efficient power management schemes to prolong lifetime, thus eliminating the need for batteries as a limited primary source of energ

  20. Smart Systems Integration for Autonomous Wireless Communications

    NARCIS (Netherlands)

    Danesh, M.

    2012-01-01

    Integration of sensors and wireless transceivers for system networking aims at emerging applications that are highly integrated, self-powered, and low cost, relying on efficient power management schemes to prolong lifetime, thus eliminating the need for batteries as a limited primary source of

  1. Smart Systems Integration for Autonomous Wireless Communications

    NARCIS (Netherlands)

    Danesh, M.

    2012-01-01

    Integration of sensors and wireless transceivers for system networking aims at emerging applications that are highly integrated, self-powered, and low cost, relying on efficient power management schemes to prolong lifetime, thus eliminating the need for batteries as a limited primary source of energ

  2. Characterizing Computation-Communication Overlap in Message-Passing Systems

    Energy Technology Data Exchange (ETDEWEB)

    David E. Bernholdt; Jarek Nieplocha; P. Sadayappan; Aniruddha G. Shet; Vinod Tipparaju

    2008-01-31

    Effective overlap of computation and communication is a well understood technique for latency hiding and can yield significant performance gains for applications on high-end computers. In this report, we describe an instrumentation framework developed for messagepassing systems to characterize the degree of overlap of communication with computation in the execution of parallel applications. The inability to obtain precise time-stamps for pertinent communication events is a significant problem, and is addressed by generation of minimum and maximum bounds on achieved overlap. The overlap measures can aid application developers and system designers in investigating scalability issues. The approach has been used to instrument two MPI implementations as well as the ARMCI system. The implementation resides entirely within the communication library and thus integrates well with existing approaches that operate outside the library. The utility of the framework is demonstrated by analyzing communication-computation overlap for micro-benchmarks and the NAS benchmarks, and the insights obtained are used to modify the NAS SP benchmark, resulting in improved overlap.

  3. Characterizing Computation-Communication Overlap in Message-Passing Systems

    Energy Technology Data Exchange (ETDEWEB)

    David E. Bernholdt; Jarek Nieplocha; P. Sadayappan; Aniruddha G. Shet; Vinod Tipparaju

    2008-01-31

    Effective overlap of computation and communication is a well understood technique for latency hiding and can yield significant performance gains for applications on high-end computers. In this report, we describe an instrumentation framework developed for message-passing systems to characterize the degree of overlap of communication with computation in the execution of parallel applications. The inability to obtain precise time-stamps for pertinent communication events is a significant problem, and is addressed by generation of minimum and maximum bounds on achieved overlap. The overlap measures can aid application developers and system designers in investigating scalability issues. The approach has been used to instrument two MPI implementations as well as the ARMCI system. The implementation resides entirely within the communication library and thus integrates well with existing approaches that operate outside the library. The utility of the framework is demonstrated by analyzing communication-computation overlap for micro-benchmarks and the NAS benchmarks, and the insights obtained are used to modify the NAS SP benchmark, resulting in improved overlap.

  4. Design and implementation of omni-directional light source and receiving system used in underwater wireless optical communication

    Science.gov (United States)

    Rao, Jionghui; Yao, Wenming; Chen, Nannan

    2013-08-01

    Underwater wireless optical communication is a communication mode which uses light as an information carrier and water as transmission medium. As a result of the inherent characteristics of the light waves, underwater wireless optical communication has the advantages of high transmission rate, good security, and strong anti-interference ability. It is suitable for high-speed, short-range communication between underwater mobile vehicles. Underwater optical wireless communication system designed in this paper is composed of the omni-directional communication light source and the receiving system. In the omni-directional communication light source, the laser beams with small divergence angle of 532nm wavelength produced by modulated laser are expanded through a combination refraction-reflection solid and then obtain more than 2π space divergence angle. The paper use TRACEPRO simulation tool to help design a combination solid composed of the lens, conical reflector and parabolic reflector, and test in the air and underwater, the result shows that the effect is fine. Unlike in the air, light attenuation is heavy in the water and a large range of variations in light intensity at different distances appear during underwater optical communication. In order to overcome this problem, the paper use a small photomultiplier as the detection device, design the receiving system using the automatic gain control technique. Underwater wireless optical communication system designed in this paper has the characteristics of small size, low power dissipation and the omni-directional communication function, it is suitable for application in the UUV, AUV, Swimmer Delivery Vehicle (SDV) and other underwater mobile platform, it realizes point-to-point communications and point-to-multipoint communications.

  5. On-line Test for Train Communication Based System

    Institute of Scientific and Technical Information of China (English)

    Zeng Xiaoqing; Masayuki Matsumoto; Kinji Mori; XU Fucang

    2002-01-01

    This paper gives out a new train automatic control system, which is based on train communication, and proposes a high assurance method to construct the system from current system. In current automatic train control (ATC) system, the central logic device detects position of each train and calculates permissible speed of each blocking section. Therefore, the central logic device controls speed of all trains. On the contrary, in the new system proposed in this paper, there is no central logical device and, train can communicate each other. The train detects the position and calculates the permissible speed itself according to the received position information of the preceding train. In the traditional method of changing an old system to a new one, test must be done off-line.While the integration technique proposed in this paper achieves on-line properties, and high assurance can be satisfied.

  6. Experimental demonstration of next-generation FSO communication system

    Science.gov (United States)

    Kazaura, Kamugisha; Omae, Kazunori; Suzuki, Toshiji; Matsumoto, Mitsuji; Mutafungwa, Edward; Asatani, Koichi; Murakami, Tadaaki; Takahashi, Koichi; Matsumoto, Hideki; Wakamori, Kazuhiko; Arimoto, Yoshinori

    2006-10-01

    Free-space optical communication has emerged as a competitive and viable technology for offering high data rates, improved capacity, cost-effective and an easy to deploy solution for providing connectivity between two points which are up to a few kilometers apart. In this paper we present experimental work which demonstrates the practicality of next generation free-space optical (FSO) communication systems suitable for short-haul, high-speed and robust data links. This experimental system is placed between two buildings in the Waseda University campus area for a communication link spanning a distance of 1 km. We outline the design of the optical antenna which uses 1550 nm wavelength and directly coupling a freespace optical beam to a single-mode fiber without the need for OE/EO conversion, to offer a communication link with data rates from 2.5 Gbps to 10 Gbps. The antenna is capable of overcoming most common limitations inherent in FSO communication systems, such as atmospheric induced beam wander and scintillation effects. A high-speed tracking mechanism which utilizes a fine positioning mirror (FPM) capable of tracking and controlling the received beam and focusing/steering most of beam power into the fiber is presented. This FPM is capable of suppressing the frequent power fluctuations caused by beam angle-of-arrival (AOA) variations. This paper presents experimental results of the FSO communication system capable offering stable performance in terms of measured bit-error-rate (BER). Performance results showing increasing the systems data rate from 2.5 Gbps to 10 Gpbs are also presented.

  7. On the average capacity and bit error probability of wireless communication systems

    KAUST Repository

    Yilmaz, Ferkan

    2011-12-01

    Analysis of the average binary error probabilities and average capacity of wireless communications systems over generalized fading channels have been considered separately in the past. This paper introduces a novel moment generating function-based unified expression for both average binary error probabilities and average capacity of single and multiple link communication with maximal ratio combining. It is a matter to note that the generic unified expression offered in this paper can be easily calculated and that is applicable to a wide variety of fading scenarios, and the mathematical formalism is illustrated with the generalized Gamma fading distribution in order to validate the correctness of our newly derived results. © 2011 IEEE.

  8. Interference Rejection Techniques in DSSS Communication System

    Institute of Scientific and Technical Information of China (English)

    GONGXiangyang; HUGuangrui

    2003-01-01

    It is known that the narrowband interfer-ence rejection capability of a direct sequence (DS) spread spectrum (SS) system can be enhanced considerably by an interference rejection algorithm prior to correlating it with the pseudo noise (PN) sequence. For narrowband gaussian noise (NGN), the techniques in common use are transver-sal filter. It models SS signal and NGN as stationary, then utilizes temporal correlation difference between SS signal and NBL however, SS signal and NGN are cyclostation-ary (CS). CS signal has correlation in frequency domain called spectrum correlation, which can not be employed by transversal filter. In this article, SS signal and NBIare modeled as CS and FRESH filter is adopted to exploit the correlation both in time domain and frequency domain.Computer simulation shows that FRESH filter can improve the system performance considerably compared with con-ventional transversal filter.

  9. Expert Systems for Computerised Wargames (Short Communication

    Directory of Open Access Journals (Sweden)

    Mohan Viakat

    2002-01-01

    Full Text Available Computerised wargaming have emerged as an important tool to train the field commanders in a cost effective manner because of its ability to incorporate all the mechanics and vagaries of warfare and at the same time reduce the cost and complexity of stage managing such training . However , while trying to convert tactical combat rules into a computerised system with the rigid limitation of software semantics.

  10. Adaptation of Hybrid FSO/RF Communication System Using Puncturing Technique

    Directory of Open Access Journals (Sweden)

    M. N. Khan

    2016-12-01

    Full Text Available Spectrum of radio frequency (RF communications is limited and expensive to install new applications. Free space optical (FSO communication is a viable technology which offers enormous bandwidth, license free installation, inexpensive deployment and error prone links. The FSO links degrade significantly due to the varying atmospheric and weather conditions (fog, cloud, snow, haze and combination of these. We propose a hybrid FSO/RF communication system which adapts the varying nature of atmosphere and weather. For the adaption of varying atmosphere and weather scenarios, we develop a novel optimization algorithm. The proposed algorithm is based on the well-known puncturing technique. We provide an extrinsic information transfer (EXIT chart for the binary and quaternary mapping scheme for the proposed communication system. We simulate the proposed algorithm for the hybrid communication system and analyze the system performance. The proposed algorithm is computationally less expensive and provide better performance gains over varying atmosphere and weather conditions. The algorithm is suitable for fast speed applications.

  11. Channel estimation for OFDM in mobile communication systems

    Science.gov (United States)

    Zheng, Kan; Zeng, Guoyan; Wang, Wenbo

    2004-04-01

    Orthogonal Frequency Division Multiplexing (OFDM)is one of the best candidates for the future mobile communication systems. This paper analyzes channel estimation algorithms for OFDM systems not only for the downlink but also for the uplink. With reasonable constraint and well-designed preambles for each user, the DFT-based uplink channel estimation algorithm on the uplink can achieve good estimation accuracy without sacrificing much system capacity. Computer simulation demonstrates effectiveness of channel estimation algorithms and conclusion is followed.

  12. Model-Based Analysis of a Windmill Communication System

    DEFF Research Database (Denmark)

    Tjell, Simon

    2006-01-01

    This paper presents the experiences obtained from modeling and analyzing a real-world application of distributed embedded computing. The modeling language Coloured Petri Nets (CPN) has been applied to analyze the properties of a communication system in a windmill, which enables a group of embedded...... computers to share a group of variables. A CPN-based model of the system is used to analyze certain real-time properties of the system....

  13. Crisis Communication in a Systems- and Medium Theoretical Perspective

    DEFF Research Database (Denmark)

    Tække, Jesper

    the paper takes into account and discusses crisis communication in relation to the new medium environment and especially in regard to social media. The conclusion is that organizations now more than ever must be observant, reflected and responsive with regard to the public opinion, because of the new, more......The academic field of crisis communication is more relevant now than ever before because of the digital media revolution, setting new standards for how to react to critics. But what is this academic field in a systems theoretical perspective? How can we understand sociological concepts like...... conflict, risk, trust, public opinion and mass media in regard to this field, and, vice versa, how can we understand crisis communication with sociologically systems theoretical concepts? This paper tries to answer these questions and thereby to contribute to the understanding of the field. Hereto...

  14. Aeronautical Mobile Airport Communications System (AeroMACS)

    Science.gov (United States)

    Budinger, James M.; Hall, Edward

    2011-01-01

    To help increase the capacity and efficiency of the nation s airports, a secure wideband wireless communications system is proposed for use on the airport surface. This paper provides an overview of the research and development process for the Aeronautical Mobile Airport Communications System (AeroMACS). AeroMACS is based on a specific commercial profile of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard known as Wireless Worldwide Interoperability for Microwave Access or WiMAX (WiMax Forum). The paper includes background on the need for global interoperability in air/ground data communications, describes potential AeroMACS applications, addresses allocated frequency spectrum constraints, summarizes the international standardization process, and provides findings and recommendations from the world s first AeroMACS prototype implemented in Cleveland, Ohio, USA.

  15. Plastic optical fiber serial communications link for distributed control system

    Science.gov (United States)

    Saxena, Piyush; Sharangpani, K. K.; Vora, H. S.; Nakhe, S. V.; Jain, R.; Shenoy, N. M.; Bhatnagar, R.; Shirke, N. D.

    2001-09-01

    One of the most common interface for communications specified is RS 232C standard. Though widely accepted, RS232 has limited transmission speed, range and networking capabilities. RS 422 standard overcomes limitations by using differential signal lines. In automation of the operation of gas discharge lasers, multiple processors are used for control of lasers, cooling system, vacuum system etc. High EMI generated by lasers interfere through galvanic transmission or by radiation over the length of cables, and hang up operation of processors or control PC. A serial communications link was designed eliminating copper transmission media, using plastic optical fiber cables and components, to connect local controllers with the master PC working on RS232 protocols. The paper discusses the design and implementation of a high ly reliable EMI harden serial communications link.

  16. Adaptive Techniques for Tactical Communication Systems

    Science.gov (United States)

    2006-12-01

    Demod . Pilot Removal Gaussian Noise SNR Estimation...SFBC transmit diversity (MISO), and one system with MRC receive diversity (SIMO). 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 x 10 4 −5 0 5 10 15 20 25 30...1.5 2 x 10 4 0 10 20 30 40 E s t i m a t e d A v e r a g e S N R [ d B ] OFDM symbol SISO MISO SIMO Adaptive Modulation: SNR 12 Dept.

  17. Hybrid Power System for Remote Communications Stations

    Science.gov (United States)

    1993-09-01

    2 ft ft ft -. .0 .0 IA .0 VINO ft Vt VI VI I............... ILl *VI - I Vt - 8* VI I Vt VI Vt Vt Vi ft ft ft ft - 4 I 0 a -.m WILl .4 I-C II) I ft...Electrical Code, New Mexico University, Las Cruces, November 1992. 35. Sandia Laboratories, Maintenance and Operation of Stand- Alone Photovoltaic Systems...Albuquerque, New Mexico , December 1991. 36. Palz, W., Solar Electricity, Chapel River Press, Andover, England, 1980. 37. Boes, E.C., "Photovoltaic

  18. Accurate Localization of Communicant Vehicles using GPS and Vision Systems

    Directory of Open Access Journals (Sweden)

    Georges CHALLITA

    2009-07-01

    Full Text Available The new generation of ADAS systems based on cooperation between vehicles can offer serious perspectives to the road security. The inter-vehicle cooperation is made possible thanks to the revolution in the wireless mobile ad hoc network. In this paper, we will develop a system that will minimize the imprecision of the GPS used to car tracking, based on the data given by the GPS which means the coordinates and speed in addition to the use of the vision data that will be collected from the loading system in the vehicle (camera and processor. Localization information can be exchanged between the vehicles through a wireless communication device. The creation of the system must adopt the Monte Carlo Method or what we call a particle filter for the treatment of the GPS data and vision data. An experimental study of this system is performed on our fleet of experimental communicating vehicles.

  19. CMOS front ends for millimeter wave wireless communication systems

    CERN Document Server

    Deferm, Noël

    2015-01-01

    This book focuses on the development of circuit and system design techniques for millimeter wave wireless communication systems above 90GHz and fabricated in nanometer scale CMOS technologies. The authors demonstrate a hands-on methodology that was applied to design six different chips, in order to overcome a variety of design challenges. Behavior of both actives and passives, and how to design them to achieve high performance is discussed in detail. This book serves as a valuable reference for millimeter wave designers, working at both the transistor level and system level.   Discusses advantages and disadvantages of designing wireless mm-wave communication circuits and systems in CMOS; Analyzes the limitations and pitfalls of building mm-wave circuits in CMOS; Includes mm-wave building block and system design techniques and applies these to 6 different CMOS chips; Provides guidelines for building measurement setups to evaluate high-frequency chips.  

  20. Rate Adaptation, Power Control, and Diversity Combining in Wireless Systems

    OpenAIRE

    Gjendemsjø, Anders Milde

    2007-01-01

    The present dissertation consists of a collection of six papers preceded byan introduction. The papers investigate the design and performance analysis of communication systems operating over wireless fading channels.Wireless communication systems carry great expectations for future services. They are expected to give users both reliable high data rate transmission and the freedom of mobility. However, due to the limited available spectral resources and the random nature of the wireless channe...

  1. Efficient Design Methods for Embedded Communication Systems

    Directory of Open Access Journals (Sweden)

    Holzer M

    2006-01-01

    Full Text Available Nowadays, design of embedded systems is confronted with complex signal processing algorithms and a multitude of computational intensive multimedia applications, while time to product launch has been extremely reduced. Especially in the wireless domain, those challenges are stacked with tough requirements on power consumption and chip size. Unfortunately, design productivity did not undergo a similar progression, and therefore fails to cope with the heterogeneity of modern architectures. Electronic design automation tools exhibit deep gaps in the design flow like high-level characterization of algorithms, floating-point to fixed-point conversion, hardware/software partitioning, and virtual prototyping. This tutorial paper surveys several promising approaches to solve the widespread design problems in this field. An overview over consistent design methodologies that establish a framework for connecting the different design tasks is given. This is followed by a discussion of solutions for the integrated automation of specific design tasks.

  2. Efficient Design Methods for Embedded Communication Systems

    Directory of Open Access Journals (Sweden)

    M. Rupp

    2006-06-01

    Full Text Available Nowadays, design of embedded systems is confronted with complex signal processing algorithms and a multitude of computational intensive multimedia applications, while time to product launch has been extremely reduced. Especially in the wireless domain, those challenges are stacked with tough requirements on power consumption and chip size. Unfortunately, design productivity did not undergo a similar progression, and therefore fails to cope with the heterogeneity of modern architectures. Electronic design automation tools exhibit deep gaps in the design flow like high-level characterization of algorithms, floating-point to fixed-point conversion, hardware/software partitioning, and virtual prototyping. This tutorial paper surveys several promising approaches to solve the widespread design problems in this field. An overview over consistent design methodologies that establish a framework for connecting the different design tasks is given. This is followed by a discussion of solutions for the integrated automation of specific design tasks.

  3. Changes in Practice Patterns of Clopidogrel in Combination with Proton Pump Inhibitors after an FDA Safety Communication

    Science.gov (United States)

    Guérin, Annie; Mody, Reema; Carter, Valerie; Ayas, Charles; Patel, Haridarshan; Lasch, Karen; Wu, Eric

    2016-01-01

    Objectives In 2009, the FDA issued a warning that omeprazole–a proton pump inhibitor (PPI)–reduces the antithrombotic effect of clopidogrel by almost half when taken concomitantly. This study aims to analyze the impact of the FDA Safety Communications on prescribing clopidogrel together with PPIs. Methods This retrospective study identified clopidogrel users from the Truven Health Analytics MarketScan Databases (01/2006–12/2012). Rates of clopidogrel-PPI combination therapy were estimated in 6-month intervals for patients with ≥1 clopidogrel prescription fill, then were analyzed pre- and post-safety communication (11/17/2009). Analyses were also conducted by grouping PPIs into CYP2C19 inhibitors (omeprazole and esomeprazole) and CYP2C19 non-inhibitors (pantoprazole, lansoprazole, dexlansoprazole, and rabeprazole). Results Overall, 483,074 patients met the selection criteria; of these, 157,248 used a clopidogrel-PPI combination. On average, 30.5% of patients in the pre- and 19.9% in the post-communication period used a clopidogrel-PPI combination therapy. Among clopidogrel users, the probability of using clopidogrel-PPI combinations fell by over 40% in the post-communication period (OR = 0.57; pomeprazole fell from 10.1% to 6.3%. Among combination therapy users, the probability of patients using a combination with a CYP2C19 inhibitor decreased by 53% (OR = 0.47; p<0.001); however, 31.5% of patients were still prescribed a clopidogrel-PPI combination therapy. Trends were similar for all and newly treated patients, regardless of clopidogrel indication and physician specialty. Conclusions The FDA Safety Communication resulted in a reduction in the number of patients undergoing combination therapy; however approximately one-third of patients still used combination therapy post-communication. PMID:26727382

  4. A Prototype HTML Training System for Graphic Communication Majors

    Science.gov (United States)

    Runquist, Roger L.

    2010-01-01

    This design research demonstrates a prototype content management system capable of training graphic communication students in the creation of basic HTML web pages. The prototype serve as a method of helping students learn basic HTML structure and commands earlier in their academic careers. Exposure to the concepts of web page creation early in…

  5. Role of Communication Networks in Behavioral Systems Analysis

    Science.gov (United States)

    Houmanfar, Ramona; Rodrigues, Nischal Joseph; Smith, Gregory S.

    2009-01-01

    This article provides an overview of communication networks and the role of verbal behavior in behavioral systems analysis. Our discussion highlights styles of leadership in the design and implementation of effective organizational contingencies that affect ways by which coordinated work practices are managed. We draw upon literature pertaining to…

  6. 21 CFR 892.2050 - Picture archiving and communications system.

    Science.gov (United States)

    2010-04-01

    ... Group (JPEG) Std., Society of Motion Picture and Television Engineers (SMPTE) Test Pattern). ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Picture archiving and communications system. 892... SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.2050 Picture archiving...

  7. The Influence of Computer-Mediated Communication Systems on Community

    Science.gov (United States)

    Rockinson-Szapkiw, Amanda J.

    2012-01-01

    As higher education institutions enter the intense competition of the rapidly growing global marketplace of online education, the leaders within these institutions are challenged to identify factors critical for developing and for maintaining effective online courses. Computer-mediated communication (CMC) systems are considered critical to…

  8. Integrated protection architectures for radars and communication systems

    NARCIS (Netherlands)

    Wanum, M. van; Monni, S.; Vliet, F.E. van

    2010-01-01

    The protection of phased array T/R modules from high input power levels is an important aspect in reducing vulnerability of radars and communication systems RF electronics in modern military platforms. Different categories of threats can damage the sensitive electronics in the phased-array radar,

  9. A multiagent system to assist elder people by TV communication

    Directory of Open Access Journals (Sweden)

    Víctor PARRA

    2015-03-01

    Full Text Available This paper presents a model that assist seniors requiring care. This system is based on a multiagent platform in order to facilitate the communication of the modules composing the model. The application allows independence for the elderly, as he is moving in a secure environment. Besides, it provides different facilities through a platform accessible to everyone, by using the TV.

  10. A Calculus of Communicating Systems with Label Passing

    DEFF Research Database (Denmark)

    Engberg, Uffe Henrik; Nielsen, Mogens

    Milner's Calculus of Communicating Systems (CCS) is extended with a mechanism for label passing - as an attempt to remedy some of the shortcomings of CCS w.r.t. dynamic change of agent interconnections. In the extended calculus, restriction is viewed formally as a binder, and the calculus allows...

  11. A Prototype HTML Training System for Graphic Communication Majors

    Science.gov (United States)

    Runquist, Roger L.

    2010-01-01

    This design research demonstrates a prototype content management system capable of training graphic communication students in the creation of basic HTML web pages. The prototype serve as a method of helping students learn basic HTML structure and commands earlier in their academic careers. Exposure to the concepts of web page creation early in…

  12. National Institute for Literacy. Literacy Information and Communication System ("LINCS")

    Science.gov (United States)

    National Institute for Literacy, 2010

    2010-01-01

    Each month, the Literacy Information and Communication System ("LINCS") will feature one of the three LINCS Resource Collections--Basic Skills, Program Management, and Workforce Competitiveness--and introduce research-based resources that practitioners can use in their adult and family literacy programs and classrooms. This edition features the…

  13. Communication Systems Simulator with Error Correcting Codes Using MATLAB

    Science.gov (United States)

    Gomez, C.; Gonzalez, J. E.; Pardo, J. M.

    2003-01-01

    In this work, the characteristics of a simulator for channel coding techniques used in communication systems, are described. This software has been designed for engineering students in order to facilitate the understanding of how the error correcting codes work. To help students understand easily the concepts related to these kinds of codes, a…

  14. The Business Communication Course and the Moodle Framework System

    Science.gov (United States)

    Krisko, Edina

    2011-01-01

    In this article I will argue that the use of learning content management systems is also justified in full-time education, especially in business education and communication studies. Nowadays not only multinational companies, but domestic medium enterprises also manage the training of new employees and existing staff with LCMSs. Companies in…

  15. DXBC: a long distance wireless broadband communication system for coastal maritime surveillance applications

    Science.gov (United States)

    Vastianos, George E.; Argyreas, Nick D.; Xilouris, Chris K.; Thomopoulos, Stelios C. A.

    2015-05-01

    The field of Homeland Security focuses on the air, land, and sea borders surveillance in order to prevent illegal activities while facilitating lawful travel and trade. The achievement of this goal requires collaboration of complex decentralized systems and services, and transfer of huge amount of information between the remote surveillance areas and the command & control centers. It becomes obvious that the effectiveness of the provided security depends highly on the available communication capabilities between the interconnected areas. Although nowadays the broadband communication between remote places is presumed easy because of the extensive infrastructure inside residential areas, it becomes a real challenge when the required information should be acquired from locations where no infrastructure is available such as mountain or sea areas. The Integrated Systems Lab of NCSR Demokritos within the PERSEUS FP7- SEC-2011-261748 project has developed a wireless broadband telecommunication system that combines different communication channels from subGHz to microwave frequencies and provides secure IP connectivity between sea surveillance vessels and the Command and Control Centers (C3). The system was deployed in Fast Patrol Boats of the Hellenic Coast Guard that are used for maritime surveillance in sea boarders and tested successfully in two demonstration exercises for irregular migration and smuggling scenarios in the Aegean Archipelagos. This paper describes in detail the system architecture in terms of hardware and software and the evaluation measurements of the system communication capabilities.

  16. Intercellular Communication in the Adaptive Immune System

    Science.gov (United States)

    Chakraborty, Arup

    2004-03-01

    Higher organisms, like humans, have an adaptive immune system that can respond to pathogens that have not been encountered before. T lymphocytes (T cells) are the orchestrators of the adaptive immune response. They interact with cells, called antigen presenting cells (APC), that display molecular signatures of pathogens. Recently, video microscopy experiments have revealed that when T cells detect antigen on APC surfaces, a spatially patterned supramolecular assembly of different types of molecules forms in the junction between cell membranes. This recognition motif is implicated in information transfer between APC and T cells, and so, is labeled the immunological synapse. The observation of synapse formation sparked two broad questions: How does the synapse form? Why does the synapse form? I will describe progress made in answering these fundamental questions in biology by synergistic use of statistical mechanical theory/computation, chemical engineering principles, and genetic and biochemical experiments. The talk will also touch upon mechanisms that may underlie the extreme sensitivity with which T cells discriminate between self and non-self.

  17. Novel 2D-sequential color code system employing Image Sensor Communications for Optical Wireless Communications

    Directory of Open Access Journals (Sweden)

    Trang Nguyen

    2016-06-01

    Full Text Available The IEEE 802.15.7r1 Optical Wireless Communications Task Group (TG7r1, also known as the revision of the IEEE 802.15.7 Visible Light Communication standard targeting the commercial usage of visible light communication systems, is of interest in this paper. The paper is mainly concerned with Image Sensor Communications (ISC of TG7r1; however, the major challenge facing ISC, as addressed in the Technical Consideration Document (TCD of TG7r1, is Image Sensor Compatibility among the variety of different commercial cameras on the market. One of the most challenging but interesting compatibility requirements is the need to support the verified presence of frame rate variation. This paper proposes a novel design for 2D-sequential color code. Compared to a QR-code-based sequential transmission, the proposed design of 2D-sequential code can overcome the above challenge that it is compatible with different frame rate variations and different shutter operations, and has the ability to mitigate the rolling effect as well as the rotating effect while effectively minimizing transmission overhead. Practical implementations are demonstrated and a performance comparison is presented.

  18. The User-level Security of Mobile Communication Systems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper studies the user-level security of mobile systems. The current mobile phone users trust the invisible security of the 2G systems. The evolution from the second-generation mobile systems (2G) to the third generation systems (3G) will introduce the threats and opportunities of the Internet to the world of mobile communications. From the technical point of view, the new security requirements are similar to the security requirements met with today in a company Intranet environment. There is, however, one great difference; the charge paid for accessing the service. In future the users of mobile systems will have to be more aware of the security issues.

  19. Communication and Language in Niklas Luhmann's Systems-Theory

    Directory of Open Access Journals (Sweden)

    Kathrin Maurer

    2010-01-01

    Full Text Available This article investigates the function and reality of language in Niklas Luhmann's systems theory. How can one interpret the systems-theoretical assumption that language is based on communication? Luhmann describes language as a dynamic media/form relationship, which is able to couple the social and psychological system. This structural coupling, which constructs consciousness and language as two autonomous systems, raises problems if one defines language from a cognitive point of view. This article discusses these problems and aims to develop assumptions and questions within the systems-theoretical approach.

  20. A digital bandlimited chaos-based communication system

    Science.gov (United States)

    Fontes, Rodrigo T.; Eisencraft, Marcio

    2016-08-01

    In recent years, many communication systems that use a function to encode an information in a chaotic signal were proposed. Since every transmission channel is bandlimited in nature, it is required to determine and to control the chaotic signal spectrum. This way, a bandlimited chaos-based communication system (CBCS) was proposed using digital filters and chaotic synchronization. As the filters modify the original chaotic system, it is necessary to study how their insertion affects chaotic synchronization. In this work, we present a digital discrete-time bandlimited CBCS system analysis, considering practical settings encountered in conventional communication systems. The proposed system is based on master-slave chaotic synchronization and the required conditions for its synchronization is obtained analytically for a general K-dimensional chaos generator map. The performance of this system is evaluated in terms of bit error rate. As a way to improve the signal to noise ratio, we also propose to filter the out-of-band noise in the receiver. Numerical simulations show the advantages of using such a scheme.

  1. Building Management System Using Windows Communication Foundation And XAML

    Directory of Open Access Journals (Sweden)

    Swarnalatha P,

    2011-04-01

    Full Text Available Building Automation System (BAS will be extended for including different kinds of information, working towards to goal of Intelligent Building Management System. The next generation ofInternet technology uses Windows Communication Foundation as middleware technology for integration of different building automation systems (BAS since Web Services will support only http protocol which is stateless. The applications used for controlling building management system (BMS components like sensors, actuators, and controllers. In this paper we propose a Service Oriented Architecture(SOA for building Management system based upon Windows Communication Foundation and XAML used for integrating different BAS.A BAS which consists of BACnet network their BMS is applied. Their exist some publically exposed Windows Communication Foundation contracts, which write and read BACnet data points from the backnet work. These contracts will be called by other enterprise applications for realize BAS integration and get real-time data on BACnet network as a facilities Management. XAML will be provided at client side GUIs for the BMS which can be reused for different kinds of applications.Finally we discuss challenges in providing security to Building Automation Systems using proposed system.

  2. Internet-Based System for Voice Communication With the ISS

    Science.gov (United States)

    Chamberlain, James; Myers, Gerry; Clem, David; Speir, Terri

    2005-01-01

    The Internet Voice Distribution System (IVoDS) is a voice-communication system that comprises mainly computer hardware and software. The IVoDS was developed to supplement and eventually replace the Enhanced Voice Distribution System (EVoDS), which, heretofore, has constituted the terrestrial subsystem of a system for voice communications among crewmembers of the International Space Station (ISS), workers at the Payloads Operations Center at Marshall Space Flight Center, principal investigators at diverse locations who are responsible for specific payloads, and others. The IVoDS utilizes a communication infrastructure of NASA and NASArelated intranets in addition to, as its name suggests, the Internet. Whereas the EVoDS utilizes traditional circuitswitched telephony, the IVoDS is a packet-data system that utilizes a voice over Internet protocol (VOIP). Relative to the EVoDS, the IVoDS offers advantages of greater flexibility and lower cost for expansion and reconfiguration. The IVoDS is an extended version of a commercial Internet-based voice conferencing system that enables each user to participate in only one conference at a time. In the IVoDS, a user can receive audio from as many as eight conferences simultaneously while sending audio to one of them. The IVoDS also incorporates administrative controls, beyond those of the commercial system, that provide greater security and control of the capabilities and authorizations for talking and listening afforded to each user.

  3. Digital microwave communication engineering point-to-point microwave systems

    CERN Document Server

    Kizer, George

    2013-01-01

    The first book to cover all engineering aspects of microwave communication path design for the digital age Fixed point-to-point microwave systems provide moderate-capacity digital transmission between well-defined locations. Most popular in situations where fiber optics or satellite communication is impractical, it is commonly used for cellular or PCS site interconnectivity where digital connectivity is needed but not economically available from other sources, and in private networks where reliability is most important. Until now, no book has adequately treated all en

  4. International Conference on Information and Communication Technology for Intelligent Systems

    CERN Document Server

    Das, Swagatam

    2016-01-01

    This volume contains 60 papers presented at ICTIS 2015: International Conference on Information and Communication Technology for Intelligent Systems. The conference was held during 28th and 29th November, 2015, Ahmedabad, India and organized communally by Venus International College of Technology, Association of Computer Machinery, Ahmedabad Chapter and Supported by Computer Society of India Division IV – Communication and Division V – Education and Research. This volume contains papers mainly focused on ICT and its application for Intelligent Computing, Cloud Storage, Data Mining, Image Processing and Software Analysis etc.

  5. Research on Communication Resource Management System based on Metamaterials

    Directory of Open Access Journals (Sweden)

    Rong Zhou

    2017-01-01

    Full Text Available Electromagnetic Metamaterial (EMM, which cannot be found in nature and possesses the novel electromagnetic properties of negative refraction, reversals of both Doppler shift and Cherenkov radiation, is a kind of artificial composed material. In order to solve the problem of long delay and high packet loss rate, the paper proposed a communication resource management system based on Metamaterials. By using the electromagnetic simulation method, the triple band and tunable transmission/reflection characteristics are investigated. Experiment result shows that the proposed method can improve the performance in the communication resource management.

  6. International Conference on Nano-electronics, Circuits & Communication Systems

    CERN Document Server

    2017-01-01

    This volume comprises select papers from the International Conference on Nano-electronics, Circuits & Communication Systems(NCCS). The conference focused on the frontier issues and their applications in business, academia, industry, and other allied areas. This international conference aimed to bring together scientists, researchers, engineers from academia and industry. The book covers technological developments and current trends in key areas such as VLSI design, IC manufacturing, and applications such as communications, ICT, and hybrid electronics. The contents of this volume will prove useful to researchers, professionals, and students alike.

  7. Conformal, Transparent Printed Antenna Developed for Communication and Navigation Systems

    Science.gov (United States)

    Lee, Richard Q.; Simons, Rainee N.

    1999-01-01

    Conformal, transparent printed antennas have advantages over conventional antennas in terms of space reuse and aesthetics. Because of their compactness and thin profile, these antennas can be mounted on video displays for efficient integration in communication systems such as palmtop computers, digital telephones, and flat-panel television displays. As an array of multiple elements, the antenna subsystem may save weight by reusing space (via vertical stacking) on photovoltaic arrays or on Earth-facing sensors. Also, the antenna could go unnoticed on automobile windshields or building windows, enabling satellite uplinks and downlinks or other emerging high-frequency communications.

  8. Ring resonator systems to perform optical communication enhancement using soliton

    CERN Document Server

    Amiri, Iraj Sadegh

    2014-01-01

    The title explain new technique of secured and high capacity optical communication signals generation by using the micro and nano ring resonators. The pulses are known as soliton pulses which are more secured due to having the properties of chaotic and dark soliton signals with ultra short bandwidth. They have high capacity due to the fact that ring resonators are able to generate pulses in the form of solitons in multiples and train form. These pulses generated by ring resonators are suitable in optical communication due to use the compact and integrated rings system, easy to control, flexibi

  9. Combined Hybrid DFE and CCK Remodulator for Medium-Range Single-Carrier Underwater Acoustic Communications

    Directory of Open Access Journals (Sweden)

    Xialin Jiang

    2017-01-01

    Full Text Available Advanced modulation and channel equalization techniques are essential for improving the performance of medium-range single-carrier underwater acoustic communications. In this paper, an enhanced detection scheme, hybrid time-frequency domain decision feedback equalizer (DFE combined with complementary code keying (CCK remodulator, is presented. CCK modulation technique provides strong tolerance to intersymbol interference caused by multipath propagation in underwater acoustic channels. The conventional hybrid DFE, using a frequency domain feedforward filter and a time domain feedback filter, provides good performance along with low computational complexity. The error propagation in the feedback filter, caused by feedbacking wrong decisions prior to CCK demodulation, may lead to great performance degradation. In our proposed scheme, with the help of CCK coding gain, more accurate remodulated CCK chips can be used as feedback. The proposed detection scheme is tested by the practical ocean experiments. The experimental results show that the proposed detection scheme ensures robust communications over 10-kilometre underwater acoustic channels with the data rate at 5 Kbits/s in 3 kHz of channel bandwidth.

  10. Combining microfluidics, optogenetics and calcium imaging to study neuronal communication in vitro.

    Science.gov (United States)

    Renault, Renaud; Sukenik, Nirit; Descroix, Stéphanie; Malaquin, Laurent; Viovy, Jean-Louis; Peyrin, Jean-Michel; Bottani, Samuel; Monceau, Pascal; Moses, Elisha; Vignes, Maéva

    2015-01-01

    In this paper we report the combination of microfluidics, optogenetics and calcium imaging as a cheap and convenient platform to study synaptic communication between neuronal populations in vitro. We first show that Calcium Orange indicator is compatible in vitro with a commonly used Channelrhodopsine-2 (ChR2) variant, as standard calcium imaging conditions did not alter significantly the activity of transduced cultures of rodent primary neurons. A fast, robust and scalable process for micro-chip fabrication was developed in parallel to build micro-compartmented cultures. Coupling optical fibers to each micro-compartment allowed for the independent control of ChR2 activation in the different populations without crosstalk. By analyzing the post-stimuli activity across the different populations, we finally show how this platform can be used to evaluate quantitatively the effective connectivity between connected neuronal populations.

  11. The emergence of information systems: a communication-based theory

    OpenAIRE

    Holten, Roland; Rosenkranz, Christoph

    2012-01-01

    An information system is more than just the information technology; it is the system that emerges from the complex interactions and relationships between the information technology and the organization. However, what impact information technology has on an organization and how organizational structures and organizational change influence information technology remains an open question. We propose a theory to explain how communication structures emerge and adapt to environmental changes. We op...

  12. An Analysis Architecture for Communications in Multi-agent Systems

    Directory of Open Access Journals (Sweden)

    Celia Gutiérrez

    2013-03-01

    Full Text Available Evaluation tools are significant from the Agent Oriented Software Engineering (AOSE point of view. Defective designs of communications in Multi-agent Systems (MAS may overload one or several agents, causing a bullying effect on them. Bullying communications have avoidable consequences, as high response times and low quality of service (QoS. Architectures that perform evaluation functionality must include features to measure the bullying activity and QoS, but it is also recommendable that they have reusability and scalability features. Evaluation tools with these features can be applied to a wide range of MAS, while minimizing designer’s effort. This work describes the design of an architecture for communication analysis, and its evolution to a modular version, that can be applied to different types of MAS. Experimentation of both versions shows differences between its executions.

  13. Quality Metrics and Reliability Analysis of Laser Communication System

    Directory of Open Access Journals (Sweden)

    A. Arockia Bazil Raj

    2016-03-01

    Full Text Available Beam wandering is the main cause for major power loss in laser communication. To analyse this prerequisite at our environment, a 155 Mbps data transmission experimental setup is built with necessary optoelectronic components for the link range of 0.5 km at an altitude of 15.25 m. A neuro-controller is developed inside the FPGA and used to stabilise the received beam at the centre of detector plane. The Q-factor and bit error rate variation profiles are calculated using the signal statistics obtained from the eye-diagram. The performance improvements on the laser communication system due to the incorporation of beam wandering mitigation control are investigated and discussed in terms of various communication quality assessment key parameters.Defence Science Journal, Vol. 66, No. 2, March 2016, pp. 175-185, DOI: http://dx.doi.org/10.14429/dsj.66.9707

  14. Collective communications apparatus and method for parallel systems

    Energy Technology Data Exchange (ETDEWEB)

    Knies, Allan D.; Keppel, David Pardo; Woo, Dong Hyuk; Fryman, Joshua B.

    2016-10-25

    A collective communication apparatus and method for parallel computing systems. For example, one embodiment of an apparatus comprises a plurality of processor elements (PEs); collective interconnect logic to dynamically form a virtual collective interconnect (VCI) between the PEs at runtime without global communication among all of the PEs, the VCI defining a logical topology between the PEs in which each PE is directly communicatively coupled to a only a subset of the remaining PEs; and execution logic to execute collective operations across the PEs, wherein one or more of the PEs receive first results from a first portion of the subset of the remaining PEs, perform a portion of the collective operations, and provide second results to a second portion of the subset of the remaining PEs.

  15. Lag Synchronization of Complex Lorenz System with Applications to Communication

    Directory of Open Access Journals (Sweden)

    Fangfang Zhang

    2015-07-01

    Full Text Available In communication, the signal at the receiver end at time t is the signal from the transmitter side at time t −Τ (Τ ≥ 0 and it is the lag time as the time lag of transmission. Therefore, lag synchronization (LS is more accurate than complete synchronization to design communication scheme. Taking complex Lorenz system as an example, we design the LS controller according to error feedback. Using chaotic masking, we propose a communication scheme based on LS and independent component analysis (ICA. It is suitable to transmit multiple messages with all kinds of amplitudes and it has the ability of anti-noise. Numerical simulations verify the feasibility and effectiveness of the presented schemes.

  16. Utilization of commercial communications systems for space based research applications

    Science.gov (United States)

    Overmyer, Carolyn; Thompson, Clark

    1998-01-01

    With the increase in utilization of space for research and development activities, the need for a communication system which improves the availability of payload uplink and downlink with the ground becomes increasingly more critical. At the same time, experiment developers are experiencing a tightening of their budgets for space based research. They don't have the capability to develop a unique communication interface that requires unique software and hardware packages. They would prefer to use commercial protocols and standards available through off-the-shelf components. Also, the need for secure communication is critical to keep proprietary data from being distributed to competing organizations. In order to meet the user community needs, SPACEHAB is currently in the process of developing and testing a system designed specifically for the user community called the SPACEHAB Universal Communication System (SHUCS). The purpose of this paper is to present customer requirements, the SHUCS design approach and top level operations, terrestrial test results, and flight testing scheduled for STS-91 and -95.

  17. Self and other in communication and cognition: the role of auto-communication and intersubjectivity in autopoiesis of psychic systems.

    Science.gov (United States)

    Märtsin, Mariann

    2008-06-01

    By referring to Niklas Luhmann's theory of self-referential systems, Aldo Mascareño (2008, submitted for publication) gives an account of system-environment interrelatedness, explaining how social and individual constitute each other through the process of communication and co-creation of meanings. Two possible extensions to his account are discussed. Firstly, auto-communication within the system that happens without any external reference needs to be taken into account while describing the existence and constant re-creation of psychic systems. Secondly, in order for the system and environment or two systems to communicate, an imagined and temporary intersubjectivity between the two needs to be assumed.

  18. Remote powering and data communication for implanted biomedical systems

    CERN Document Server

    Kilinc, Enver Gurhan; Maloberti, Franco

    2016-01-01

    This book describes new circuits and systems for implantable biomedical applications and explains the design of a batteryless, remotely-powered implantable micro-system, designed for long-term patient monitoring.  Following new trends in implantable biomedical applications, the authors demonstrate a system which is capable of efficient, remote powering and reliable data communication.  Novel architecture and design methodologies are used to transfer power with a low-power, optimized inductive link and data is transmitted by a reliable communication link.  Additionally, an electro-mechanical solution is presented for tracking and monitoring the implantable system, while the patient is mobile.  ·         Describes practical example of an implantable batteryless biomedical system; ·         Analyzes and compares various energy harvesting and power transfer methods; ·         Describes design of remote powering link and data communication of the implantable system, comparing differe...

  19. The Iridium (tm) system: Personal communications anytime, anyplace

    Science.gov (United States)

    Hatlelid, John E.; Casey, Larry

    The Iridium system is designed to provide handheld personal communications between diverse locations around the world at any time and without prior knowledge of the location of the personal units. This paper provides an overview of the system, the services it provides, its operation, and an overview of the commercial practices and relatively high volume satellite production techniques which will make the system cost effective. A constellation of 66 satellites will provide an orbiting, spherical-shell, infrastructure for this global calling capability. The satellites act as tall cellular towers and allow convenient operation for portable handheld telephones. The system will provide a full range of services including voice, paging, data, geolocation, and fax capabilities. Motorola is a world leader in the production of high volume, high quality, reliable telecommunications hardware. One of Iridium's goals is to apply these production techniques to high reliability space hardware. Concurrent engineering, high performance work teams, advanced manufacturing technologies, and improved assembly and test methods are some of the techniques that will keep the Iridium system cost effective. Mobile, global, flexible personal communications are coming that will allow anyone to call or receive a call from/to anyplace at anytime. The Iridium system will provide communications where none exist today. This connectivity will allow increased information transfer, open new markets for various business endeavors, and in general increase productivity and development.

  20. Combining speech recognition software with Digital Imaging and Communications in Medicine (DICOM) workstation software on a Microsoft Windows platform.

    Science.gov (United States)

    Ernst, R; Carpenter, W; Torres, W; Wheeler, S

    2001-06-01

    This presentation describes our experience in combining speech recognition software, clinical review software, and other software products on a single computer. Different processor speeds, random access memory (RAM), and computer costs were evaluated. We found that combining continuous speech recognition software with Digital Imaging and Communications in Medicine (DICOM) workstation software on the same platform is feasible and can lead to substantial savings of hardware cost. This combination optimizes use of limited workspace and can improve radiology workflow.

  1. Towards Co-Engineering Communicating Autonomous Cyber-Physical Systems

    Science.gov (United States)

    Bujorianu, Marius C.; Bujorianu, Manuela L.

    2009-01-01

    In this paper, we sketch a framework for interdisciplinary modeling of space systems, by proposing a holistic view. We consider different system dimensions and their interaction. Specifically, we study the interactions between computation, physics, communication, uncertainty and autonomy. The most comprehensive computational paradigm that supports a holistic perspective on autonomous space systems is given by cyber-physical systems. For these, the state of art consists of collaborating multi-engineering efforts that prompt for an adequate formal foundation. To achieve this, we propose a leveraging of the traditional content of formal modeling by a co-engineering process.

  2. An Adaptive Bandwidth Allocation for Energy Efficient Wireless Communication Systems

    Institute of Scientific and Technical Information of China (English)

    Yung-Fa Huang,Che-Hao Li; Chuan-Bi Lin; Chia-Chi Chang

    2015-01-01

    Abstract―In this paper, an energy efficient bandwidth allocation scheme is proposed for wireless communication systems. An optimal bandwidth expansion (OBE) scheme is proposed to assign the available system bandwidth for users. When the system bandwidth does not reach the full load, the remaining bandwidth can be energy-efficiently assigned to the other users. Simulation results show that the energy efficiency of the proposed OBE scheme outperforms the traditional same bandwidth expansion (SBE) scheme. Thus, the proposed OBE can effectively assign the system bandwidth and improve energy efficiency.

  3. Telementoring and teleparamedic communication platforms and robotic systems for battlefield biomedical applications

    Science.gov (United States)

    Jannson, Tomasz P.; Kostrzewski, Andrew A.; Zeltser, Gregory; Forrester, Thomas

    2000-08-01

    A new approach to C4, in the form of supercomputer-path soft communication and computing (SC2), provides enabling technology baseline for teleparamedic and telementoring communication platforms and robotic systems. In particular, this new information technology offers full-duplex 2-D and/or 3-D wireless communication and interactive telepresence, as well as remotely-controlled semi-automatic sensing, within so-called telementoring scheme, being the specific brand of telemedicine. In this paper, we discuss the SC2 capabilities, including: 20-times, higher than prior art, compression of digital multimedia data (especially including digital video) with computing power higher than the of 100 Pentiums. The further extension of SC2- technologies, combined with nearly-autonomous teleparamedic scheme, will be also discussed.

  4. Using the combination refraction-reflection solid to design omni-directional light source used in underwater wireless optical communication

    Science.gov (United States)

    Rao, Jionghui; Yao, Wenming; Wen, Linqiang

    2015-10-01

    Underwater wireless optical communication is a communication technology which uses laser as an information carrier and transmits data through water. Underwater wireless optical communication has some good features such as broader bandwidth, high transmission rate, better security, anti—interference performance. Therefore, it is promising to be widely used in the civil and military communication domains. It is also suitable for high-speed, short-range communication between underwater mobile vehicles. This paper presents a design approach of omni-directional light source used in underwater wireless optical communication, using TRACEPRO simulation tool to help design a combination solid composed of the lens, conical reflector and parabolic reflector, and using the modulated DPSS green laser in the transmitter module to output the laser beam in small divergence angles, after expanded by the combination refraction-reflection solid, the angle turns into a space divergence angle of 2π, achieving the omni-directional light source of hemisphere space, and test in the air and underwater, the result shows that the effect is fine. This paper analyzes the experimental test in the air and water, in order to make further improvement of the uniformity of light distribution, we optimize the reflector surface parameters of combination refraction-reflection solid and test in the air and water. The result shows that omni-directional light source used in underwater wireless optical communication optimized could achieve the uniformity of light distribution of underwater space divergence angle of 2π. Omni-directional light source used in underwater wireless optical communication designed in this paper has the characteristics of small size and uniformity of light distribution, it is suitable for application between UUVs, AUVs, Swimmer Delivery Vehicles (SDVs) and other underwater vehicle fleet, it realizes point-to-multipoint communications.

  5. Radiation-Hardened Electronics for Advanced Communications Systems

    Science.gov (United States)

    Whitaker, Sterling

    2015-01-01

    Novel approach enables high-speed special-purpose processors Advanced reconfigurable and reprogrammable communication systems will require sub-130-nanometer electronics. Legacy single event upset (SEU) radiation-tolerant circuits are ineffective at speeds greater than 125 megahertz. In Phase I of this project, ICs, LLC, demonstrated new base-level logic circuits that provide SEU immunity for sub-130-nanometer high-speed circuits. In Phase II, the company developed an innovative self-restoring logic (SRL) circuit and a system approach that provides high-speed, SEU-tolerant solutions that are effective for sub-130-nanometer electronics scalable to at least 22-nanometer processes. The SRL system can be used in the design of NASA's next-generation special-purpose processors, especially reconfigurable communication processors.

  6. The principle of the positioning system based on communication satellites

    Institute of Scientific and Technical Information of China (English)

    AI GuoXiang; SHI HuLi; WU HaiTao; LI ZhiGang; GUO Ji

    2009-01-01

    It is a long dream to realize the communication and navigation functionality in a satellite system in the world.This paper introduces how to establish the system,a positioning system based on communication satellites called Chinese Area Positioning System (CAPS).Instead of the typical navigation satelIites,the communication satellites are configured firstly to transfer navigation signals from ground stations,and can be used to obtain service of the positioning,velocity and time,and to achieve the function of navigation and positioning.Some key technique issues should be first solved; they include the accuracy position determination and orbit prediction of the communication satellites,the measuring and calculation of transfer time of the signals,the carrier frequency drift in communication satellite ignal transfer,how to improve the geometrical configuration of the constellation in the system,and the integration of navigation & communication.Several innovative methods are developed to make the new system have full functions of navigation and communication.Based on the development of crucial techniques and methods,the CAPS demonstration system has been designed and developed.Four communication satellites in the geosynchronous orbit (GEO) located at 87.5°E,110.5°E,134°E,142°E and barometric altimetry are used in the CAPS system.The GEO satellites located at 134°E and 142°E re decommissioned GEO (DGEO) satellites.C-band is used as the navigation band.Dual frequency at C1=4143.15 MHz and C2=3826.02 MHz as well as dual codes with standard code (CA code and precision code (P code)) are adopted.The ground segment consists of five ground stations; the master station is in Lintong,Xi'an.The ground stations take a lot of responsibilities,including monitor and management of the operation of all system components,determination of the satellite position and prediction of the satellite orbit,accomplishment of the virtual atomic clock measurement,transmission and receiving

  7. The principle of the positioning system based on communication satellites

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    It is a long dream to realize the communication and navigation functionality in a satellite system in the world. This paper introduces how to establish the system, a positioning system based on communication satellites called Chinese Area Positioning System (CAPS). Instead of the typical navigation satellites, the communication satellites are configured firstly to transfer navigation signals from ground stations, and can be used to obtain service of the positioning, velocity and time, and to achieve the function of navigation and positioning. Some key technique issues should be first solved; they include the accuracy position determination and orbit prediction of the communication satellites, the measur- ing and calculation of transfer time of the signals, the carrier frequency drift in communication satellite signal transfer, how to improve the geometrical configuration of the constellation in the system, and the integration of navigation & communication. Several innovative methods are developed to make the new system have full functions of navigation and communication. Based on the development of crucial techniques and methods, the CAPS demonstration system has been designed and developed. Four communication satellites in the geosynchronous orbit (GEO) located at 87.5°E, 110.5°E, 134°E, 142°E and barometric altimetry are used in the CAPS system. The GEO satellites located at 134°E and 142°E are decommissioned GEO (DGEO) satellites. C-band is used as the navigation band. Dual frequency at C1=4143.15 MHz and C2=3826.02 MHz as well as dual codes with standard code (CA code and precision code (P code)) are adopted. The ground segment consists of five ground stations; the master station is in Lintong, Xi’an. The ground stations take a lot of responsibilities, including monitor and management of the operation of all system components, determination of the satellite position and prediction of the satellite orbit, accomplishment of the virtual atomic clock

  8. 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...

  9. Laser Ground System for Communication Experiments with ARTEMIS

    Science.gov (United States)

    Kuzkov, Volodymyr; Volovyk, Dmytro; Kuzkov, Sergii; Sodnik, Zoran; Pukha, Sergii; Caramia, Vincenzo

    2012-10-01

    The ARTEMIS satellite with the OPALE laser communication terminal on-board was launched on 12 July, 2001. 1789 laser communications sessions were performed between ARTEMIS and SPOT-4 (PASTEL) from 01 April 2003 to 09 January 2008 with total duration of 378 hours. Regular laser communication experiments between ESA's Optical Ground Station (OGS - altitude 2400 m above see level) and ARTEMIS in various atmosphere conditions were also performed. The Japanese Space Agency (JAXA) launched the KIRARI (OICETS) satellite with laser communication terminal called LUCE. Laser communication links between KIRARI and ARTEMIS were successfully realized and international laser communications experiments from the KIRARI satellite were also successfully performed with optical ground stations located in the USA (JPL), Spain (ESA OGS), Germany (DLR), and Japan (NICT). The German Space Agency (DLR) performed laser communication links between two LEO satellites (TerraSAR-X and NFIRE), demonstrating data transfer rates of 5.6Gbit/s and performed laser communication experiments between the satellites and the ESA optical ground station. To reduce the influence of weather conditions on laser communication between satellites and ground stations, a network of optical stations situated in different atmosphere regions needs to be created. In 2002, the Main Astronomical Observatory (MAO) started the development of its own laser communication system to be placed into the Cassegrain focus of its 0.7m AZT-2 telescope (Fe = 10.5m), located in Kyiv 190 meters above sea level. The work was supported by the National Space Agency of Ukraine and by ESA ARTEMIS has an orbital position of 21.4° E and an orbital inclination of more than 9.75°. As a result we developed a precise tracking system for AZT-2 telescope (weighing more than 2 tons) using micro-step motors. Software was developed for computer control of the telescope to track the satellite's orbit and a tracking accuracy of 0.6 arcsec was achieved

  10. Modified function projective combination synchronization of hyperchaotic systems

    Indian Academy of Sciences (India)

    K SEBASTIAN SUDHEER; M SABIR

    2017-03-01

    In this work, a novel combination synchronization scheme in which synchronization of a new combination hyperchaotic drive system formed by combining state variables of the original drive system with appropriate scaling factors with a response hyperchaotic system is considered. A self-combination system is constructed from hyperchaotic Lorenz system by combining state variables of the Lorenz system with appropriate scaling factors. Modified function projective synchronization between the newly constructed combination hyperchaotic Lorenz system and hyperchaotic Lu system is investigated using adaptive method. By Lyapunov stability theory, the adaptive control law and the parameter update law are derived to make the state of two systems as modified function projective synchronized. Numerical simulations are done to show the validity and effectiveness of the proposed synchronization scheme.

  11. Comparison of Communication Architectures for Spacecraft Modular Avionics Systems

    Science.gov (United States)

    Gwaltney, D. A.; Briscoe, J. M.

    2006-01-01

    This document is a survey of publicly available information concerning serial communication architectures used, or proposed to be used, in aeronautic and aerospace applications. It focuses on serial communication architectures that are suitable for low-latency or real-time communication between physically distributed nodes in a system. Candidates for the study have either extensive deployment in the field, or appear to be viable for near-term deployment. Eleven different serial communication architectures are considered, and a brief description of each is given with the salient features summarized in a table in appendix A. This survey is a product of the Propulsion High Impact Avionics Technology (PHIAT) Project at NASA Marshall Space Flight Center (MSFC). PHIAT was originally funded under the Next Generation Launch Technology (NGLT) Program to develop avionics technologies for control of next generation reusable rocket engines. After the announcement of the Space Exploration Initiative, the scope of the project was expanded to include vehicle systems control for human and robotics missions. As such, a section is included presenting the rationale used for selection of a time-triggered architecture for implementation of the avionics demonstration hardware developed by the project team

  12. A highly innovative global broadband mobile communication system concept

    Science.gov (United States)

    Wittig, Manfred

    2010-04-01

    Global mobile communication systems deployed in the 1990s (Iridium and Globalstar) failed to achieve the expected market success. However, recently a second generation of these two LEO constellations have been or will be procured. This shows evidence that global mobile satellite communications are attractive for a certain class of users. Basic requirements for mobile satellite communication networks are global coverage at high elevation angles, continuous availability and most important attractive service offers. For the first two reasons LEO constellations were designed and deployed. The large number of required satellites (remember the original Teledesic concept was designed containing 860 satellites) increases the CAPEX and consequently the service cost. This is probably the major reason for the limited commercial success of Iridium and Globalstar. An ideal global mobile (broadband) communication system shall provide global coverage at high elevation angles (not below e.g. 30°) with the lowest number of satellites. This seems to be contradictory. However, a solution will be presented that achieves global coverage which requires only five satellites and achieves high elevation angles even at polar locations. This orbit constellation is to be complemented with innovative payloads to achieve cost efficient broadband mobile services all over the Globe. Innovative L/S-band payload concepts will be introduced as well as Ka-band payloads.

  13. Interference of GSM mobile phones with communication between Cardiac Rhythm Management devices and programmers: A combined in vivo and in vitro study.

    Science.gov (United States)

    Huang, Dong; Dong, Zhi-Feng; Chen, Yan; Wang, Fa-Bin; Wei, Zhi; Zhao, Wen-Bin; Li, Shuai; Liu, Ming-Ya; Zhu, Wei; Wei, Meng; Li, Jing-Bo

    2015-07-01

    To investigate interference, and how to avoid it, by high-frequency electromagnetic fields (EMFs) of Global System for Mobile Communications (GSM) mobile phone with communication between cardiac rhythm management devices (CRMs) and programmers, a combined in vivo and in vitro testing was conducted. During in vivo testing, GSM mobile phones interfered with CRM-programmer communication in 33 of 65 subjects tested (50.8%). Losing ventricle sensing was representative in this study. In terms of clinical symptoms, only 4 subjects (0.6%) felt dizzy during testing. CRM-programmer communication recovered upon termination of mobile phone communication. During in vitro testing, electromagnetic interference by high-frequency (700-950 MHz) EMFs reproducibly occurred in duplicate testing in 18 of 20 CRMs (90%). During each interference, the pacing pulse signal on the programmer would suddenly disappear while the synchronous signal was normal on the amplifier-oscilloscope. Simulation analysis showed that interference by radiofrequency emitting devices with CRM-programmer communication may be attributed to factors including materials, excitation source distance, and implant depth. Results suggested that patients implanted with CRMs should not be restricted from using GSM mobile phones; however, CRMs should be kept away from high-frequency EMFs of GSM mobile phone during programming.

  14. Communications and control for electric power systems: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kirkham, H.

    1998-04-01

    This report is a summary of some of the work done on the Communications and Control project, with particular emphasis on the achievements during the years 1986--1996. During those years, the project moved away from concern with dispersed storage and generation and its impact on power system operation (the team was responsible for studies in this area, and for making a power system simulator that included DSG), and became involved in more concrete work aimed at applying high-tech solutions to problems of power system communications and control. This report covers work done at JPL on the following topics: (1) the measurement of electric and magnetic fields, both ac and dc; (2) the use of optical power to supply low-power electronics; (3) the design of a fault-tolerant communication system designed for distribution automation; and (4) a digital phase locked loop that allows the use of low-power transmitting electronics to recreate a good-quality signal at the receiver. In a report of this kind, only the results and highlights of the work are described.

  15. FQPSK techniques for satellite and mobile radio communications systems

    Science.gov (United States)

    Li, Yazhuo; Tang, Jing; Tao, Xiaofeng

    2005-11-01

    A continuous phase modulation (CPM) and constant envelope modulation (CEM) alternative of Feher-Patented quadrature phase-shift keying (FQPSK) modulation technique is presented. It is found to provide good spectral efficiencies, power efficiencies, and bit error rate (BER) performance. The modulation schemes of FQPSK are described. The spectral efficiencies, BER performance are also compared with FQPSK and other modulation techniques which are widely used in current mobile and cordless radio standards. The results show that FQPSK modulated signal exhibits much less spectrum spreading than QPSK, OQPSK, and MSK, and the error probability performance of the FQPSK is superior to those in narrow-band nonlinear channels. Based on that, the system capacity and power dissipation are also analyzed for communication systems. It is found that the encoder or receiver for the FQPSK signal to be fully compatible with original I/Q modulated one. FQPSK technique is suitable for nonlinear channels, such as satellite and mobile communications systems reducing the AM/AM and AM/PM adverse effects. At last it is also attempted to extend the application in 3G (CDMA) and 4G (OFDM) mobile communications systems.

  16. A communication model for interlinking national tsunami early warning systems

    Science.gov (United States)

    Lendholt, M.; Hammitzsch, M.; Esbri Palomares, M. A.

    2012-04-01

    The integration of national Tsunami Early Earning Systems (TEWS) to ocean-wide networks is a main objective of the UNESCO Intergovernmental Oceanic Commission (IOC) tsunami programme. The intention is to interlink national TEWSs leveraging warning communication during hazards. For this purpose a communication model has been developed enabling an efficient message exchange within a centre-to-centre (C2C) communication in a system-of-systems environment. The model, designed to be robust and simple, is based on existing interoperability standards from the Open Geospatial Consortium (OGC) and the Organization of the Advancement of Structured Information Standards (OASIS). For the exchange of tsunami warning bulletins the Common Alerting Protocol (CAP) is used. It supports geospatial referencing by addressing geocoded Points of Interests (POIs), Areas of Interest (AOIs) and Coastal Forecast Zones (CFZs). Moreover it supports hazard classification by standardized criticality parameters and the transmission of attachments, e.g. situation maps. The communication model also supports the exchange of sensor observations and measurements such as sea level data or earthquake parameters. For this purpose markup languages of the Sensor Web Enablement (SWE) suite are used. Both communication products, warning bulletins and sensor observations, are embedded in an envelope providing addressing and routing information using the Emergency Data Exchange Language Distribution Element (EDXL-DE). The communication model has been implemented in a first pilot based on Message Oriented Middleware (MOM). Implementation, test and validation was started in the European research project Distant Early Warning System (DEWS) and is continued successively in the project Collaborative, Complex, and Critical Decision Processes in Evolving Crises (TRIDEC). Stimulated by the concepts and results of the German Indonesian Tsunami Early Warning System (GITEWS) and based on its sensor integration platform

  17. Performance analysis of multihop coherent OFDM free-space optical communication systems

    Science.gov (United States)

    Wang, Yi; Wang, Deli; Ma, Jing

    2016-10-01

    This paper proposes a multihop coherent orthogonal frequency division multiplexing free space optical (OFDM-FSO) communication system model based on a relay transmission mode of decode and forward (DF) with the Gamma-Gamma channel. In the study of atmospheric statistical model, mainly considering the combined action by the following three aspects, they are the light intensity scintillation caused by the atmospheric turbulence, the pointing error caused the transmitter and the receiver without aiming at each other and the path loss. We derived closed-form expressions of outage probability and symbol error rate of the multihop coherent OFDM-FSO system with serial DF relay transmission. We simulated and analyzed the influence of the atmospheric turbulence, the modulation order, the beam width and the jitter factor on the communication interruption performance and bit error performance of the multihop coherent OFDM-FSO system with different number of hops.

  18. Present and Future Trends in Military Satellite Communication Systems

    Directory of Open Access Journals (Sweden)

    C.K. Chatterjee

    1993-01-01

    Full Text Available Recent years have seen a phenomenal growth in the field of satellite communications. Satcom systems offer many advantages for military applications which include wide area coverage, rapid deployment, flexible networking and long range service to moving platforms like ships, aircraft and vehicles. This paper gives an overview of the special features and future trends in military satcom systems. A brief account of various countermeasures against threats, use of EHF, spread-spectrum techniques and on board processing has also been given. Major technological advances are anticipated in near future to realise high capacity, secure and survivable satcom systems for Defence applications.

  19. An Online Banking System Based on Quantum Cryptography Communication

    Science.gov (United States)

    Zhou, Ri-gui; Li, Wei; Huan, Tian-tian; Shen, Chen-yi; Li, Hai-sheng

    2014-07-01

    In this paper, an online banking system has been built. Based on quantum cryptography communication, this system is proved unconditional secure. Two sets of GHZ states are applied, which can ensure the safety of purchase and payment, respectively. In another word, three trading participants in each triplet state group form an interdependent and interactive relationship. In the meantime, trading authorization and blind signature is introduced by means of controllable quantum teleportation. Thus, an effective monitor is practiced on the premise that the privacy of trading partners is guaranteed. If there is a dispute or deceptive behavior, the system will find out the deceiver immediately according to the relationship mentioned above.

  20. Performance of PLL synchronized optical PPM communication systems

    Science.gov (United States)

    Chen, C.-C.; Gardner, C. S.

    1986-01-01

    Receiver timing synchronization of an optical PPM communication system can be achieved using a phase-locked loop (PLL) if the photodetector output is properly processed. The synchronization performance is shown to improve with increasing signal power and decreasing loop bandwidth. The bit error rate performance of the PLL synchronized PPM system is analyzed and compared to that of the perfectly synchronized system. It is shown that the increase in signal power needed to compensate for the imperfect sychronization is small (less than 0.1 dB) for loop bandwidths less than 0.1 percent of the slot frequency.

  1. A network communication and recording system for digital seismic observation

    Institute of Scientific and Technical Information of China (English)

    WANG Hong-ti; ZHUANG Can-tao; XUE Bing; LI Jiang; CHEN Yang; ZHU Xiao-yi; LOU Wen-yu; LIU Ming-hui

    2006-01-01

    A network communication and recording system based on China-made ARCA SOC and embedded Linux operating system is introduced in this paper. It supports TCP/IP network communication protocol and mass storage medium. It has strong points of self-monitor, low power consumption, high timing accuracy, high reliability of operation, etc. It can serve up to 20 centers real-time waveform data at the same time. It meets not only the requirements of physical networking observation, but also virtual networking observation based on Intemet in which real-time data transmission is required. Its ability of field recording also meets the requirements of portable seismic observation, strong motion observation and seismic exploration observation, etc.

  2. Semiconductor Mode-Locked Lasers for Optical Communication Systems

    DEFF Research Database (Denmark)

    Yvind, Kresten

    2003-01-01

    The thesis deals with the design and fabrication of semiconductor mode-locked lasers for use in optical communication systems. The properties of pulse sources and characterization methods are described as well as requirements for application in communication systems. Especially, the importance of......, and ways to reduce high-frequency jitter is discussed. The main result of the thesis is a new design of the epitaxial structure that both enables simplified fabrication and improves the properties of monolithic lasers. 40 GHz monolithic lasers with record low jitter and high power is presented as well...... as the first 10 GHz all-active monolithic laser with both short pulses and low jitter.Results from external cavity mode-locked lasers are also reported along with an investigation of the influence of the operating conditions on the performance of the device. Antireflection coatings are a critical limiting...

  3. An Orbiting Standards Platform for communication satellite system RF measurements

    Science.gov (United States)

    Wallace, R. G.; Woodruff, J. J.

    1978-01-01

    The Orbiting Standards Platform (OSP) is a proposed satellite dedicated to performing RF measurements on space communications systems. It would consist of a quasi-geostationary spacecraft containing an ensemble of calibrated RF sources and field strength meters operating in several microwave bands, and would be capable of accurately and conveniently measuring critical earth station and satellite RF performance parameters, such as EIRP, gain, figure of merit (G/T), crosspolarization, beamwidth, and sidelobe levels. The feasibility and utility of the OSP concept has been under joint study by NASA, NBS, Comsat and NTIA. A survey of potential OSP users was conducted by NTIA as part of this effort. The response to this survey, along with certain trends in satellite communications system design, indicates a growing need for such a measurement service.

  4. FLYCON-R: Wireless Integrated Communication and Navigation System

    Science.gov (United States)

    Palomo, Jose Maria; Gomez de Aguero, Sergio; Latorre, Antonio; Fernandez, Antonio; Pina, Fernando; Tarziu, Andrei; Balan, Mugurel; Sanchez Gestido, Manuel; Concari, Paolo

    2015-09-01

    This paper presents the FLYCON-R system, which is an integrated communication and ranging system based on OFDM signal. FLYCON-R supports high data rates and flexible data communications, providing also relative ranging measurements based on Time of Arrival (ToA) from the Radio Frequency signals. Deimos Space (Spain and Romania) and ISS are carrying out the FLYCON-R project for ESA under the Romanian task force initiative. FLYCON-R (Prototype of Integrated Nav-Com sensor based on WiMax Standard for Formation Flying) aims to upgrade the previously existing FLYCON proof of concept (PoC) to a more advanced, elegant breadboard version, ready for on-ground flight testing and as near as possible to a future flight version. The paper presents as well the preliminary results of the flight tests performed on the Spanish R&D PERIGEO project, using the FLYCON PoC prototypes.

  5. A protocol for secure communication in large distributed systems

    Science.gov (United States)

    Anderson, D. P.; Ferrari, D.; Rangan, P. V.; Sartirana, B.

    1987-01-01

    A mechanism for secure communication in large distributed systems is proposed. The mechanism, called Authenticated Datagram Protocol (ADP), provides message authentication and, optionally, privacy of data. ADP is a host-to-host datagram protocol, positioned below the transport layer; it uses public-key encryption to establish secure channels between hosts and to authenticate owners, and single-key encryption for communication over a channel and to ensure privacy of the messages. ADP is shown to satisfy the main security requirements of large distributed systems, to provide end-to-end security in spite of its relatively low level, and to exhibit several advantages over schemes in which security mechanisms are at a higher level. The results of a trace-driven measurement study of ADP performance show that its throughput and latency are acceptable even within the limitations of today's technology, provided single-key encryption/decryption can be done in hardware.

  6. Optimal collective communication algorithms in grid computing system

    Institute of Scientific and Technical Information of China (English)

    Wu Yanhui; Lu Xinda

    2005-01-01

    With computational grid, running parallel program on large-scale and geographically distributed computer systems is feasible. It is a difficult task to write parallel applications which may require changing the communication structure of the applications. MPI's collective operations allow for some of these changes to be hidden from the applications programmer. We have developed optimal collective communication algorithms optimized for wide area systems and have taken hierarchical network structure into account. Both the bandwidth and the latency of the LAN and WAN links differ by almost two orders of magnitude. Our algorithms are designed to send the minimal amount of data over the slow wide area links, and to only incur a single wide area latency. Compared to MPICH that do not consider the topology, large performance improvements are possible.

  7. The Synthesis Method of Automated System of Operational Planning in Low-Space Communication System Messaging

    Directory of Open Access Journals (Sweden)

    Serhii Kovbasiuk

    2017-04-01

    Full Text Available One of the reasons for the decrease of efficiency in low-speed communication systems, satellite communication, which are based on nanoplatform is a high degree of operational planning centralisation. To overcome this problem the method which carries out the distribution of tasks of communications operational planning minimizing the exchange of information between spatially remote sites, and takes into account the computing performance of software and hardware was developed. The technique is based on the use of methods of structural and parametric synthesis, simulation and statistical analysis of the results. Its use allows to obtain the optimal structure of the automated system of operational planning in low-space communication system messaging evaluation of efficiency in terms of fixed communication of information load.

  8. Health Monitoring System Based on Intra-Body Communication

    Science.gov (United States)

    Razak, A. H. A.; Ibrahim, I. W.; Ayub, A. H.; Amri, M. F.; Hamzi, M. H.; Halim, A. K.; Ahmad, A.; Junid, S. A. M. Al

    2015-11-01

    This paper presents a model of a Body Area Network (BAN) health monitoring system based on Intra-Body Communication. Intra-body Communication (IBC) is a communication technique that uses the human body as a medium for electrical signal communication. One of the visions in the health care industry is to provide autonomous and continuous self and the remote health monitoring system. This can be achieved via BAN, LAN and WAN integration. The BAN technology itself consists of short range data communication modules, sensors, controller and actuators. The information can be transmitted to the LAN and WAN via the RF technology such as Bluetooth, ZigBee and ANT. Although the implementations of RF communication have been successful, there are still limitations in term of power consumption, battery lifetime, interferences and signal attenuations. One of the solutions for Medical Body Area Network (MBANs) to overcome these issues is by using an IBC technique because it can operate at lower frequencies and power consumption compared to the existing techniques. The first objective is to design the IBC's transmitter and receiver modules using the off the shelf components. The specifications of the modules such as frequency, data rate, modulation and demodulation coding system were defined. The individual module were designed and tested separately. The modules was integrated as an IBC system and tested for functionality then was implemented on PCB. Next objective is to model and implement the digital parts of the transmitter and receiver modules on the Altera's FPGA board. The digital blocks were interfaced with the FPGA's on board modules and the discrete components. The signals that have been received from the transmitter were converted into a proper waveform and it can be viewed via external devices such as oscilloscope and Labview. The signals such as heartbeats or pulses can also be displayed on LCD. In conclusion, the IBC project presents medical health monitoring model

  9. Distributed Mobile Robot Localization and Communication System for Special Interventions

    OpenAIRE

    Sales Gil, Jorge

    2011-01-01

    This thesis focuses on the development of a distributed mobile robot localization and communication system for special interventions like those carried out by fire-fighters in fire ground search and rescue. The use case scenario is related to the one described for the GUARDIANS EU project, where a swarm formation of mobile robots accompany a fire fighter during a rescue intervention in a warehouse. In this line, localizing the robots and the fire fighter during an indoor intervention with the...

  10. An Automatic Interference Recognition Method in Spread Spectrum Communication System

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-ming; TAO Ran

    2007-01-01

    An algorithm to detect and recognize interferences embedded in a direct sequence spread spectrum (DSSS) communication system is proposed. Based on Welch's averaging modified periodogram method and fractional Fourier transformation (FRFT), the paper proposes a decision tree-based algorithm in which a set of decision criteria for identifying different types of interferences is developed. Simulation results demonstrate that the proposed algorithm provides a high recognition rate and is robust for various ISR and SNR.

  11. Secure Communication System Based on Chaos in Optical Fibre

    Institute of Scientific and Technical Information of China (English)

    Pak; L; Chu; Fan; Zhang; William; Mak; Robust; Lai

    2003-01-01

    1 IntroductionRecently, there have been intense research activities on the study of synchronized chaos generated by fibre lasers and its application to secure communication systems. So far, all studies concentrate on two aspects: (1) the effect of the transmission channel between the transmitter and the receiver has been neglected, and (2) the chaos and the signal are carried by one wavelength. Both theoretical and experimental investigations make

  12. Propagation Impact on Modern HF (High Frequency) Communications System Design

    Science.gov (United States)

    1986-03-01

    US Gvt Printing Office, Washington DC. Piggot, W.R., Rawer, K. (1972). URSI Handbook for lonogram Interpretation and... Handbook ", Communications Research Centre Report No. 1255, 1974. Widrow B., Mantey P.E., Griffiths L.J. and Goode B.B., "Adaptive Antenna Systems...implemented in modified form by the terminal node controller (TNC). In the U.S., Amateur Radio Relay League ( ARRL ) radio amateurs have held four annual

  13. Innovative Techniques for Antenna Synthesis in Modern Wireless Communication Systems

    OpenAIRE

    Leonardo, Lizzi

    2011-01-01

    This thesis deals with the study and development of innovative techniques for the synthesis of antennas able to fulfill the tight requirements of modern wireless communication systems. By exploiting the advantages given by the use of geometries based on spline and fractal shapes, the aim of the proposed synthesis techniques is the design of small Ultra-Wideband (UWB) and multi-band antennas. The synthesis of UWB antennas is carried out by means of two different approaches which consider the a...

  14. System analysis for millimeter-wave communication satellites

    Science.gov (United States)

    Holland, L. D.; Hilsen, N. B.; Gallagher, J. J.; Stevens, G.

    1980-01-01

    Research and development needs for millimeter-wave space communication systems are presented. Assumed propagation fade statistics are investigated along with high data rate diversity link and storage. The development of reliable ferrite switches, and high performance receivers and transmitters is discussed, in addition to improved tolerance of dish and lens fabrication for the antennas. The typical cost for using a simplex voice channel via a high capacity 40/50 GHz satellite is presented.

  15. Stabilization of Networked Control Systems: Designing Effective Communication Sequences

    Science.gov (United States)

    2004-01-01

    IEEE Transactions on Automatic Control 45(7), 1279–1289. Elia, N. and S. K. Mitter (2001). Stabilization...of linear systems with limited information. IEEE Transactions on Automatic Control 46(9), 1384–1400. Hristu-Varsakelis, D. (2001). Feedback control...and R. W. Brockett (1997). Sys- tems with finite communication bandwidth constraints. i. state estimation problems.. IEEE Transactions on Automatic Control

  16. Combining Content and Elements of Communication into an Upper-Level Biochemistry Course

    Science.gov (United States)

    Whittington, Carli P.; Pellock, Samuel J.; Cunningham, Rebecca L.; Cox, James R.

    2014-01-01

    This report describes how a science communication module was incorporated into an advanced biochemistry course. Elements of communication were taught synergistically with biochemistry content in this course in an effort to expose students to a variety of effective oral communication strategies. Students were trained to use these established…

  17. A chaotic spread spectrum system for underwater acoustic communication

    Science.gov (United States)

    Ren, Hai-Peng; Bai, Chao; Kong, Qingju; Baptista, Murilo S.; Grebogi, Celso

    2017-07-01

    Acoustic communication is a key technology to exchange information underwater, which is of great significance to explore marine resources and to marine defense. The underwater acoustic channel is a time-space-frequency varying channel characterized by serious multipath effect, limited frequency band, complex environmental noises and significant Doppler frequency shift phenomenon, which makes underwater acoustic communication with low Bit Error Rate (BER) to be a challenging task. A novel chaotic spread spectrum acoustic communication method with low BER is proposed in this paper. A chaotic signal, generated by a hybrid dynamical system, is used as a spread spectrum sequence at the transmitter end. At the receiver end, a corresponding chaotic matched filter is used to offset the effect of multipath propagation and noise. The proposed method does not require the complicated equalization and modulation-demodulation technologies that are necessary for conventional acoustic communication. Simulation results show that the proposed method has good anti-interference ability and lower BER as compared to other traditional methods.

  18. Consensus of Multiagent Systems With Distance-Dependent Communication Networks.

    Science.gov (United States)

    Jing, Gangshan; Zheng, Yuanshi; Wang, Long

    2016-08-29

    In this paper, we study the consensus problem of discrete-time and continuous-time multiagent systems with distance-dependent communication networks, respectively. The communication weight between any two agents is assumed to be a nonincreasing function of their distance. First, we consider the networks with fixed connectivity. In this case, the interaction between adjacent agents always exists but the influence could possibly become negligible if the distance is long enough. We show that consensus can be reached under arbitrary initial states if the decay rate of the communication weight is less than a given bound. Second, we study the networks with distance-dependent connectivity. It is assumed that any two agents interact with each other if and only if their distance does not exceed a fixed range. With the validity of some conditions related to the property of the initial communication graph, we prove that consensus can be achieved asymptotically. Third, we present some applications of the main results to opinion consensus problems and formation control problems. Finally, several simulation examples are presented to illustrate the effectiveness of the theoretical findings.

  19. Programmable System on Chip Distributed Communication and Control Approach for Human Adaptive Mechanical System

    OpenAIRE

    Ahmad A.M. Faudzi; Suzumori, K

    2010-01-01

    Problem statement: Communication and control are two main components in any Mechatronics system. They can be designed either by centralized or decentralized approach. Both approaches can be chosen based on application designed and specific requirements of the designer. In this study, decentralized or normally called distributed approach was selected to solved communication and control of a human adaptive mechanical system namely Intelligent Chair Tools (ICT). The ICT seating system is powered...

  20. Radio-wave propagation for space communications systems

    Science.gov (United States)

    Ippolito, L. J.

    1981-01-01

    The most recent information on the effects of Earth's atmosphere on space communications systems is reviewed. The design and reliable operation of satellite systems that provide the many applications in space which rely on the transmission of radio waves for communications and scientific purposes are dependent on the propagation characteristics of the transmission path. The presence of atmospheric gases, clouds, fog, precipitation, and turbulence causes uncontrolled variations in the signal characteristics. These variations can result in a reduction of the quality and reliability of the transmitted information. Models and other techniques are used in the prediction of atmospheric effects as influenced by frequency, geography, elevation angle, and type of transmission. Recent data on performance characteristics obtained from direct measurements on satellite links operating to above 30 GHz have been reviewed. Particular emphasis has been placed on the effects of precipitation on the Earth/space path, including rain attenuation, and ice particle depolarization. Other factors are sky noise, antenna gain degradation, scintillations, and bandwidth coherence. Each of the various propagation factors has an effect on design criteria for communications systems. These criteria include link reliability, power margins, noise contribution, modulation and polarization factors, channel cross talk, error rate, and bandwidth limitations.

  1. The Peace System – As a Self-Referential Communication System

    DEFF Research Database (Denmark)

    Harste, Gorm

    2013-01-01

    Peace communication as diplomatic communication is an often neglected phenomenon in social and political theory that concerns problems of international order, justice and peace. Political philosophy seldom embarks on the theme with more than a few comments. Yet, throughout history, diplomacy has...... developed in opposition to violence and war exactly when they transgress dividing lines allowing for cross-cultural and even cross-stratified communication. The article’s main point is to describe how such communication codes about peace and diplomacy can be described in recent social theory...... of communication, and to get some added value in this respect, Niklas Luhmann’s theory of self-referential communication systems has been applied....

  2. Design of FFT Algorithm in OFDM Communication System

    Directory of Open Access Journals (Sweden)

    Baddi.Yedukondalu,

    2014-01-01

    Full Text Available The present communication system is limited by three major factors. Those are System capacity, higher data rates and interference. To meet these requirements, 802.11-based wireless LANs has fascinated interest in providing higher data rates and greater system capacities. Among them, the 802.11a standard based on OFDM (Orthogonal Frequency Division Multiplexing modulation scheme is defined to meet high-speed and large-system-capacity challenges. To implement OFDM System, FFT (Fast Fourier Transform and IFFT (Inverse Fast Fourier Transform are the major hardware requirements. The System capacity is increased by increasing the FFT processor size. Higher data rates are achieved by proper architecture of FFT. This paper presents the design of a 256 point modified 22 pipelined FFT/IFFT processor to achieve the higher data rates. And data constellation, symbol detection at transmitter and receiver is done by using QPSK (Quadrature Phase Shift Keying Modulation for easy of designing in OFDM communication system. The design has been coded in Verilog and the simulations and synthesis are carried out by using Xilinx 9.2i.

  3. MEMS-based Circuits and Systems for Wireless Communication

    CERN Document Server

    Kaiser, Andreas

    2013-01-01

    MEMS-based Circuits and Systems for Wireless Communication provides comprehensive coverage of RF-MEMS technology from device to system level. This edited volume places emphasis on how system performance for radio frequency applications can be leveraged by Micro-Electro-Mechanical Systems (MEMS). Coverage also extends to innovative MEMS-aware radio architectures that push the potential of MEMS technology further ahead.  This work presents a broad overview of the technology from MEMS devices (mainly BAW and Si MEMS resonators) to basic circuits, such as oscillators and filters, and finally complete systems such as ultra-low-power MEMS-based radios. Contributions from leading experts around the world are organized in three parts. Part I introduces RF-MEMS technology, devices and modeling and includes a prospective outlook on ongoing developments towards Nano-Electro-Mechanical Systems (NEMS) and phononic crystals. Device properties and models are presented in a circuit oriented perspective. Part II focusses on ...

  4. Fault Detection of Computer Communication Networks Using an Expert System

    Directory of Open Access Journals (Sweden)

    Ibrahiem M.M. El Emary

    2005-01-01

    Full Text Available The main objective of this study was to build an expert system for assisting the network administrator in his work of management and administration of the computer communication network. Theory of operation of the proposed expert system depends on using a time series model capable of forecasting the various performance parameters as: delay, utilization and collision frequency. When the expert system finds a difference (with certain tolerance between the predicted value and the measured value, it informs the network administrator that there exist problems in his network either in the switch or link or router. We examine two types of network by our proposed expert system, the first one is called token bus while the second one is called token ring. When we run our expert system on these two types of computer networks, actually the expert system captures the problem when there exists an excess deviation from the network performance parameters.

  5. Complex systems relationships between control, communications and computing

    CERN Document Server

    2016-01-01

    This book gives a wide-ranging description of the many facets of complex dynamic networks and systems within an infrastructure provided by integrated control and supervision: envisioning, design, experimental exploration, and implementation. The theoretical contributions and the case studies presented can reach control goals beyond those of stabilization and output regulation or even of adaptive control. Reporting on work of the Control of Complex Systems (COSY) research program, Complex Systems follows from and expands upon an earlier collection: Control of Complex Systems by introducing novel theoretical techniques for hard-to-control networks and systems. The major common feature of all the superficially diverse contributions encompassed by this book is that of spotting and exploiting possible areas of mutual reinforcement between control, computing and communications. These help readers to achieve not only robust stable plant system operation but also properties such as collective adaptivity, integrity an...

  6. Performance study of an OFDM visible light communication system based on white LED array

    Science.gov (United States)

    Tian, Chong-Wen; Li, Yan-Ting; Ye, Wei-Lin; Quan, Xiang-Yin; Song, Zhanwei; Zheng, Chuan-Tao

    2011-11-01

    By introducing orthogonal frequency division multiplexing (OFDM) technology, a visible light communication (VLC) system using a 5×5 white LED array is studied in this paper. The OFDM transmitter and receiver are modeled through MATLAB/Simulink tool. The electrical-optical-electrical (EOE) response of the VLC channel, which is also the response of the detector, is derived based on Lambert's lighting model. Then the modeling on the overall OFDM/VLC system is established by combining the above three models together. The effects of the factors which include the digital modulation, Reed-Solomon (RS) coding, pilot form, pilot ratio (PR) and communication distance on the bit error rate (BER) of the system are discussed. The results show that through the use of RS coding, block pilot, quadrate phase shift keying (QPSK) modulation and a suitable pilot ratio about 1/3, under the communication rate about 550 kbit/s, the BER can be dropped to below 10-5, and the communication distance can reach 0.9 m.

  7. Performance study of an OFDM visible light communication system based on white LED array

    Institute of Scientific and Technical Information of China (English)

    TIAN Chong-wen; LI Yan-ting; YE Wei-lin; QUAN Xiang-yin; SONG Zhan-wei; ZHENG Chuan-tao

    2011-01-01

    By introducing orthogonaI frequency division multiplexing (OFDM) technology,a visible light communication (VLC) system using a 5×5 white LED array is studied in this paper.The OFDM transmitter and receiver are modeled through MATLAB/Simulink tool.The electrical optical-electrical (EOE) response of the VLC channel,which is also the response of the detector,is derived based on Lambert's lighting model.Then the modeling on the overall OFDM/VLC system is established by combining the above three models together.The effects of the factors which include the digital modulation,Reed-Solomon (RS) coding,pilot form,pilot ratio (PR) and communication distance on the bit error rate (BER) of the system are discussed.The results show that through the use of RS coding,block pilot,quadrate phase shift keying (QPSK) modulation and a suitable pilot ratio about 1/3,under the communication rate about 550 kbit/s,the BER can be dropped to below 10s,and the communication distance can reach 0.9 m.

  8. Combining content and elements of communication into an upper-level biochemistry course.

    Science.gov (United States)

    Whittington, Carli P; Pellock, Samuel J; Cunningham, Rebecca L; Cox, James R

    2014-01-01

    This report describes how a science communication module was incorporated into an advanced biochemistry course. Elements of communication were taught synergistically with biochemistry content in this course in an effort to expose students to a variety of effective oral communication strategies. Students were trained to use these established techniques and incorporated them into various presentations throughout the course. Three students describe their use of specific resources and how the skills learned relate to their future career. The importance and relevance of science communication are receiving unprecedented national attention. The academic scientific community must respond by incorporating more communication-centered instruction and opportunities in the classroom and laboratory.

  9. General Systems Theory: Application To The Design Of Speech Communication Courses

    Science.gov (United States)

    Tucker, Raymond K.

    1971-01-01

    General systems theory can be applied to problems in the teaching of speech communication courses. The author describes general systems theory as it is applied to the designing, conducting and evaluation of speech communication courses. (Author/MS)

  10. Combining communication technology utilization and organizational innovation: evidence from Canadian healthcare decision makers.

    Science.gov (United States)

    Jbilou, Jalila; Landry, Réjean; Amara, Nabil; El Adlouni, Salaheddine

    2009-08-01

    Information and Communication Technology (ICT) and Organizational Innovation (OI) are seen as the miracle of post-modernity in organizations. In this way, they are supposed to resolve most organizational problems, efficiently and rapidly. OI is highly dependent on the capacity and the investment in knowledge management (internal and external) to support decision making process and to implement significant changes. We know what explains ICT utilization (ICTU) and what determines OI development (OID) in healthcare services. Moreover, the literature tends to link ICTU to OID and vice versa. However, this dependency has never been explored empirically through the lens of roles combination. To identify the existing combined roles profiles of ICTU and OID among healthcare decision makers and determine factors of the shift from a profile to another. We did the following: (1) a structured review of the literature on healthcare management by focusing on ICTU and OID which allowed us to build two indexes and a comprehensive framework; (2) a copula methodology to identify with high precision the thresholds for ICTU and OID; and (3) a cross-sectional study based on a survey done with a sample of 942 decision makers from Canadian healthcare organizations through a multinomial logit model to identify determinants of the shift. ICTU and OID are correlated at 22% (Kendal's Tau). The joint distribution (combination) of ICTU and OID shows that four major profiles exist among decision makers in Canadian healthcare organizations: the traditional decision maker, the innovative decision maker, the technologic decision maker and the contemporary decision maker. We found out that classic factors act as barriers to the shift from one profile to the desired profile (from 1 to 4, from 2 to 4 and from 3 to 4). We have identified that the attitude toward research and relational capital are transversal barriers of shift. We have also found that some factors have a specific impact such as

  11. A Survey of Wireless Communications for the Electric Power System

    Energy Technology Data Exchange (ETDEWEB)

    Akyol, Bora A.; Kirkham, Harold; Clements, Samuel L.; Hadley, Mark D.

    2010-01-27

    A key mission of the U.S. Department of Energy (DOE) Office of Electricity Delivery and Energy Reliability (OE) is to enhance the security and reliability of the nation’s energy infrastructure. Improving the security of control systems, which enable the automated control of our energy production and distribution, is critical for protecting the energy infrastructure and the integral function that it serves in our lives. The DOE-OE Control Systems Security Program provides research and development to help the energy industry actively pursue advanced security solutions for control systems. The focus of this report is analyzing how, where, and what type of wireless communications are suitable for deployment in the electric power system and to inform implementers of their options in wireless technologies. The discussions in this report are applicable to enhancing both the communications infrastructure of the current electric power system and new smart system deployments. The work described in this report includes a survey of the following wireless technologies: • IEEE 802.16 d and e (WiMAX) • IEEE 802.11 (Wi-Fi) family of a, b, g, n, and s • Wireless sensor protocols that use parts of the IEEE 802.15.4 specification: WirelessHART, International Society of Automation (ISA) 100.11a, and Zigbee • The 2, 3, and 4 generation (G )cellular technologies of GPRS/EDGE/1xRTT, HSPA/EVDO, and Long-Term Evolution (LTE)/HSPA+UMTS.

  12. Implementation of Wireless Communications Systems on FPGA-Based Platforms

    Directory of Open Access Journals (Sweden)

    Voros NS

    2007-01-01

    Full Text Available Wireless communications are a very popular application domain. The efficient implementation of their components (access points and mobile terminals/network interface cards in terms of hardware cost and design time is of great importance. This paper describes the design and implementation of the HIPERLAN/2 WLAN system on a platform including general purpose microprocessors and FPGAs. Detailed implementation results (performance, code size, and FPGA resources utilization are presented. The main goal of the design case presented is to provide insight into the design aspects of a complex system based on FPGAs. The results prove that an implementation based on microprocessors and FPGAs is adequate for the access point part of the system where the expected volumes are rather small. At the same time, such an implementation serves as a prototyping of an integrated implementation (System-on-Chip, which is necessary for the mobile terminals of a HIPERLAN/2 system. Finally, firmware upgrades were developed allowing the implementation of an outdoor wireless communication system on the same platform.

  13. Implementation of Wireless Communications Systems on FPGA-Based Platforms

    Directory of Open Access Journals (Sweden)

    N. S. Voros

    2007-02-01

    Full Text Available Wireless communications are a very popular application domain. The efficient implementation of their components (access points and mobile terminals/network interface cards in terms of hardware cost and design time is of great importance. This paper describes the design and implementation of the HIPERLAN/2 WLAN system on a platform including general purpose microprocessors and FPGAs. Detailed implementation results (performance, code size, and FPGA resources utilization are presented. The main goal of the design case presented is to provide insight into the design aspects of a complex system based on FPGAs. The results prove that an implementation based on microprocessors and FPGAs is adequate for the access point part of the system where the expected volumes are rather small. At the same time, such an implementation serves as a prototyping of an integrated implementation (System-on-Chip, which is necessary for the mobile terminals of a HIPERLAN/2 system. Finally, firmware upgrades were developed allowing the implementation of an outdoor wireless communication system on the same platform.

  14. Design of a Combined Beacon Receiver and Digital Radiometer for 40 GHz Propagation Measurements at the Madrid Deep Space Communications Complex

    Science.gov (United States)

    Zemba, Michael J.; Nessel, James A.; Morabito, David D.

    2017-01-01

    NASA Glenn Research Center (GRC) and the Jet Propulsion Laboratory (JPL) have jointly developed an atmospheric propagation terminal to measure and characterize propagation phenomena at 40 GHz at the Madrid Deep Space Communications Complex (MDSCC) in Robledo de Chavela, Spain. The hybrid Q-band system combines a 40 GHz beacon receiver and digital radiometer into the same RF front-end and observes the 39.402 GHz beacon of the European Space Agencys Alphasat Aldo Paraboni TDP5 experiment. The goals of these measurements are to assist MDSCC mission operations as well as to contribute to the development and improvement of International Telecommunications Union (ITU) models for prediction of communications systems performance within the Q-band. Herein, we provide an overview of the system design, characterization, and plan of operations to commence at the MDSCC beginning in March 2017.

  15. Visible Light Communication System Using an Organic Bulk Heterojunction Photodetector

    Directory of Open Access Journals (Sweden)

    Cristina de Dios

    2013-09-01

    Full Text Available A visible light communication (VLC system using an organic bulk heterojunction photodetector (OPD is presented. The system has been successfully proven indoors with an audio signal. The emitter consists of three commercial high-power white LEDs connected in parallel. The receiver is based on an organic photodetector having as active layer a blend of poly(3-hexylthiophene (P3HT and phenyl C61-butyric acid methyl ester (PCBM. The OPD is opto-electrically characterized, showing a responsivity of 0.18 A/W and a modulation response of 790 kHz at −6 V.

  16. Stochastic network optimization with application to communication and queueing systems

    CERN Document Server

    Neely, Michael

    2010-01-01

    This text presents a modern theory of analysis, control, and optimization for dynamic networks. Mathematical techniques of Lyapunov drift and Lyapunov optimization are developed and shown to enable constrained optimization of time averages in general stochastic systems. The focus is on communication and queueing systems, including wireless networks with time-varying channels, mobility, and randomly arriving traffic. A simple drift-plus-penalty framework is used to optimize time averages such as throughput, throughput-utility, power, and distortion. Explicit performance-delay tradeoffs are prov

  17. Capacity and Performance of MIMO systems for Wireless Communications

    Directory of Open Access Journals (Sweden)

    E. Ghayoula

    2014-08-01

    Full Text Available This paper presents the capacity performance of multiple antennas for wireless communication systems. Multiple antennas structures can be classified into single-input multiple-outputs (SIMO, multiple-inputs single output (MISO, and multiple-inputs multiple-outputs (MIMO systems. Assuming that the channel is unknown at receiver, capacity expressions are provided for each structure. Our results also show that increasing the number of transmitting and receiving antennas for a wireless MIMO channel does indeed improve the channel capacity that can be obtained.

  18. Display For Command, Control, Communication and Intelligence System

    Directory of Open Access Journals (Sweden)

    S. Prabhu

    1998-04-01

    Full Text Available Display subsystem is an important part of command, control, communication and intelligence(C31 system. The display used in C31 system for air defence should provide a panoramic view of thecomplete air segment under its command and control in real-time. The necessary information requiredfor taking a quick decision should be available to the commander in easily understandable graphicformat This paper describes salient features of the display known as synthetic radar situation display(SRSD developed by the Defence Electronics Research Laboratory (DLRL, Hyderabad, for such applications

  19. Experimental Characterization of Extremely Broadband THz Impulse Radio Communication Systems

    DEFF Research Database (Denmark)

    Yu, Xianbin; Vidal, Borja; Galili, Michael

    2015-01-01

    We experimentally characterize a ultrabroadband terahertz (THz) impulse radio system with up to 10 GHz repetition rate. THz generation and radiation are realized in an antenna-integrated uni-traveling-carrier photodiode (UTC-PD), and THz reception is implemented based on photoconductive sampling...... by using a photoconductive antenna (PCA). We analyze the performance in terms of bandwidth and the features of the THz pulses. A 15 dB bandwidth of 1 THz confirms that this THz impulse system has a great potential of supporting ultrafast data rates, eventually for Terabit wireless communication era....

  20. Streetlight Control System Based on Wireless Communication over DALI Protocol

    Directory of Open Access Journals (Sweden)

    Francisco José Bellido-Outeiriño

    2016-04-01

    Full Text Available Public lighting represents a large part of the energy consumption of towns and cities. Efficient management of public lighting can entail significant energy savings. This work presents a smart system for managing public lighting networks based on wireless communication and the DALI protocol. Wireless communication entails significant economic savings, as there is no need to install new wiring and visual impacts and damage to the facades of historical buildings in city centers are avoided. The DALI protocol uses bidirectional communication with the ballast, which allows its status to be controlled and monitored at all times. The novelty of this work is that it tackles all aspects related to the management of public lighting: a standard protocol, DALI, was selected to control the ballast, a wireless node based on the IEEE 802.15.4 standard with a DALI interface was designed, a network layer that considers the topology of the lighting network has been developed, and lastly, some user-friendly applications for the control and maintenance of the system by the technical crews of the different towns and cities have been developed.