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Sample records for suspended patch antenna

  1. Improved Gain Microstrip Patch Antenna

    Science.gov (United States)

    2015-08-06

    PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION...08-2015 Publication Improved Gain Microstrip Patch Antenna David A. Tonn Naval Under Warfare Center Division, Newport 1176 Howell St., Code 00L...Distribution A An antenna for mounting on a ground plane includes a dielectric substrate for mounting on the ground plane. A conductive patch

  2. Collinear Microstrip Patch Antenna

    Directory of Open Access Journals (Sweden)

    M. Mazanek

    2005-12-01

    Full Text Available The paper presents a brief overview of the development of so calledcollinear types of antenna arrays. A new type of this structure inmicrostrip technology is further introduced. The principle of theantenna operation is explained via surface current distribution ofexcited modes. Such distribution is reached via geometricalperturbation of a radiating element by slots introduced in such a waythat they e liminate radiation from even half current wavelengths . Theinitial design and optimization of the prototype operating in RFID band(869 MHz has been performed in planar simulator Zeland IE3D. Aprototype has been realized and measured. The reached results show thatthe presented antenna has directional character as it can be expecteddue to the proposed technology and the presence of a planar groundplane.

  3. Wireless link design using a patch antenna

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E

    2000-08-11

    A wireless link was designed using a patch antenna. In the process, several different models were tested. Testing proved a patch antenna was a viable solution for building a wireless link within the design specifications. Also, this experimentation provided a basis for future patch antenna design.

  4. Numerical analysis of patch antenna as antenna array element

    OpenAIRE

    Kizimenko, V.; Bobkov, Y

    2009-01-01

    The patch antennas as antenna array element can be modeling by finite element method (programs Microwave Office, Ansoft HFSS and other). But this method need to use fast computer with memory large size. In this work the authors make an attempt to use thin wire integral equation method for patch antenna analysis. The results of modeling by proposed method are compared with the same of modeling by finite elements method and experimental results.

  5. Metamaterial Embedded Wearable Rectangular Microstrip Patch Antenna

    Directory of Open Access Journals (Sweden)

    J. G. Joshi

    2012-01-01

    Full Text Available This paper presents an indigenous low-cost metamaterial embedded wearable rectangular microstrip patch antenna using polyester substrate for IEEE 802.11a WLAN applications. The proposed antenna resonates at 5.10 GHz with a bandwidth and gain of 97 MHz and 4.92 dBi, respectively. The electrical size of this antenna is 0.254λ×0.5λ. The slots are cut in rectangular patch to reduce the bending effect. This leads to mismatch the impedance at WLAN frequency band; hence, a metamaterial square SRR is embedded inside the slot. A prototype antenna has been fabricated and tested, and the measured results are presented in this paper. The simulated and measured results of the proposed antenna are found to be in good agreement. The bending effect on the performance of this antenna is experimentally verified.

  6. Study on composite photonic crystal patch antenna

    Science.gov (United States)

    Lu, N. D.; Zhou, Y. Q.; Shen, T. G.; Ji, P. L.; Sun, J.; Yuan, B. G.; Yu, F. C.

    2009-09-01

    The paper investigated a composite photonic crystal patch antenna by using the method of finite difference time domain (FDTD). The results show that there exists a wave resonance state at 2.635GHz, where the real part of the permittivity and permeability are all negative; its refraction index is -1. The effect has largely enhanced the electromagnetic wave's resonance intensity, and has improved the localized extent of electromagnetic energy obviously in such photonic crystal structure (PBG), resulting in a higher antenna gain, a lower return loss, and a better improvement of the antenna's characteristics. Due to such the advantages, the use of patch antennas can be extended to such fields as mobile communication, satellite communication, aviation, etc.

  7. Tunable Patch Antennas Using Microelectromechanical Systems

    Science.gov (United States)

    2011-05-11

    unloaded 5.5 GHz patch antennas .....................................................23 Figure 17: Spin - coater and hot plate used for circuit board...light. Spin -coating applies an even layer of photoresist across the plate Simulated with Sonnet™ 24 surfaces. A photograph of the spin - coater ...and hot plate used for circuit board fabrication is shown as Figure 17. Figure 17: Spin - coater and hot plate used for circuit board fabrication The

  8. Miniaturization of Multiple-Layer Folded Patch Antennas

    DEFF Research Database (Denmark)

    Zhang, Jiaying; Breinbjerg, Olav

    2009-01-01

    A new folded patch antenna with multiple layers was developed in this paper, by folding the patch in a proper way, and a highly miniaturized antenna can be realized. The multiple layer patch with 4-layer and 6-layer are designed and evaluated at 2.4 GHz, 915 MHz, and 415 MHz respectively. Then a 4...... layer patch is fabricated and measured to validate the design method. The theoretical analysis, design and simulations, fabrications, as well as the measurements are presented in this paper. All the results show that the folded patch antenna is a good candidate in making a highly miniaturized compact...... antenna....

  9. Dual-Band Microstrip Patch Antenna Miniaturization Using Metamaterial

    Directory of Open Access Journals (Sweden)

    Indrasen Singh

    2013-01-01

    Full Text Available A dual-band microstrip patch antenna is designed and analyzed using metamaterial artificial substrate. Metamaterial based substrate is designed using Square Split Ring Resonator (SSRR and Wire Strip. The antenna is tuned to work at two resonating frequencies in the frequency range from 1 GHz to 4 GHz depending on the geometric specifications of SSRR, strip line, radiating patch, and feed location point. Proposed antenna provides good return loss behavior at both resonating frequencies. The obtained VSWR at both resonating frequencies is very much near to 1. Proposed antenna covers applications in mobile communication and Wi-MAX. Proposed patch antenna is compared with the conventional patch antenna, which shows the significant miniaturization as compared to conventional patch antenna.

  10. Zero Index Metamaterial for Designing High-Gain Patch Antenna

    Directory of Open Access Journals (Sweden)

    Yahong Liu

    2013-01-01

    Full Text Available A planar wideband zero-index metamaterial (ZIM based on mesh grid structure is studied. It is demonstrated that the real part of the index approaches zero at the wideband covering from 9.9 GHz to 11.4 GHz. Two conventional patch antennas whose operating frequencies are both in the range of zero-index frequencies are designed and fabricated. And then, the ZIM is placed in the presence of the conventional patch antennas to form the proposed antennas. The distance between the antenna and the ZIM cover is investigated. Antenna performances are studied with simulations and measurements. The results show that the more directional and higher gain patch antennas can be obtained. The measured results are in good agreement with the simulations. Compared to the conventional patch antenna without the ZIM, it is shown that the beamwidth of antenna with the ZIM cover becomes more convergent and the gain is much higher.

  11. Circularly Polarized Slotted Microstrip Patch Antenna with Finite Ground Plane

    Directory of Open Access Journals (Sweden)

    Sanyog Rawat

    2012-12-01

    Full Text Available In this paper a new geometry of circularly polarized patch antenna is proposed with improved bandwidth. The radiation performance of proposed patch antenna is investigated using IE3D simulation software and its performance is compared with that of conventional rectangular patch antenna. The simulated return loss, axial ratio and impedance with frequency for the proposed antenna are reported in this paper. It is shown that by selecting suitable ground-plane dimensions, air gap and location of the slots, the impedance bandwidth can be enhanced upto 10.15% as compared to conventional rectangular patch (4.24% with an axial ratio bandwidth of 4.05%.

  12. multiband millimeter wave t-shaped antenna with optimized patch ...

    African Journals Online (AJOL)

    Adamu Halilu

    This paper proposed a simple T-shaped patch antenna for millimeter waveband frequency operation. Millimeter wave is a frequency ranges between 30GHz to 300GHz in an electromagnetic spectrum. The proposed antenna consists of T- shape radiating patch mounted on rectangular substrate (FR4-4) and microstrip line ...

  13. Performance Enhancement of the Patch Antennas Applying Micromachining Technology

    Directory of Open Access Journals (Sweden)

    Mohamed N. Azermanesh

    2007-09-01

    Full Text Available This paper reports on the application of micromachining technology for performance enhancement of two types of compact antennas which are becoming a common practice in microsystems. Shorted patch antennas (SPA and folded shorted patch antennas operating in the 5-6 GHz ISM band, with intended application in short-range wireless communications, are considered. The electrical length of antennas are modified by etching the substrate of the antennas, thus providing a new degree of freedom to control the antenna operating properties, which is the main novelty of our work. The gain and bandwidth of the antennas are increased by increasing the etching depth. However, etching the substrate affects the operating frequency as well. To keep the operating frequency at a pre-specified value, the dimension of the antennas must be increased by deepening the etching depth. Therefore, a trade off between the performance enhancement of the antennas and the dimensional enlargement is required.

  14. Microstrip Patch Antenna Design with Artificial Material Loadings

    OpenAIRE

    Calafell Rueda, Irene

    2009-01-01

    Conventional microstrip patch antennas can be easily miniaturized by increasing the substrate electric permittivity (εr) although the fractional bandwith (FBW) is dramatically decreased. In this work, the use of metamaterials as artificial antenna substrates is studied as an alternative method to eficiently miniaturize patch antennas, accounting not only electric permittivity εr but also magnetic permeability μr. In addition, a compact FBW formulation proposed by Yaghjian et al. [10] is ap...

  15. Use of microstrip patch antennas in grain permittivity measurement

    Science.gov (United States)

    El Sabbagh, M.A.; Ramahi, O.M.; Trabelsi, S.; Nelson, S.O.; Khan, L.

    2003-01-01

    In this paper, a compact size free-space setup is proposed for the measurement of complex permittivity of granular materials. The horn antennas in the conventional setup are replaced by microstrip patch antennas which is a step toward system miniaturization. The experimental results obtained are in good agreement with those obtained with horn antennas.

  16. Composite GPS Patch Antenna for the AR Bandwidth Enhancement

    Directory of Open Access Journals (Sweden)

    Minkil Park

    2016-01-01

    Full Text Available A composite Global Positioning System (GPS patch antenna with a quadrature 3 dB hybrid coupler was designed and implemented for working RHCP and had a broadband axial ratio (AR bandwidth. We designed two patches as a FR-4 patch and 1.5 mm thickness thin ceramic patch with a quadrature 3 dB hybrid coupler. A CP radiation pattern was achieved, and the AR bandwidth improved by incorporating a quadrature 3 dB hybrid coupler feed structure in a micro-strip patch antenna. SMD by chip elements was applied to the quadrature 3 dB hybrid coupler. For the composite FR-4 and ceramic patch antennas, the VSWR measurement showed a 2 : 1 ratio over the entire design band, and the 3 dB AR bandwidth was 295 and 580 MHz for the FR-4 patch and ceramic patch antennas, respectively. The antenna gains for the composite FR-4 and ceramic patch antennas were measured as 1.36–2.75 and 1.47–2.71 dBi with 15.11–25.3% and 19.25–28.45% efficiency, respectively.

  17. Analysis of Microstrip Line Fed Patch Antenna for Wireless Communications

    Directory of Open Access Journals (Sweden)

    Singh Ashish

    2017-11-01

    Full Text Available In this paper, theoretical analysis of microstrip line fed rectangular patch antenna loaded with parasitic element and split-ring resonator is presented. The proposed antenna shows that the dualband operation depends on gap between parasitic element, split-ring resonator, length and width of microstrip line. It is found that antenna resonates at two distinct resonating modes i.e., 0.9 GHz and 1.8 GHz for lower and upper resonance frequencies respectively. The antenna shows dual frequency nature with frequency ratio 2.0. The characteristics of microstrip line fed rectangular patch antenna loaded with parasitic element and split-ring resonator antenna is compared with other prototype microstrip line fed antennas. Further, the theoretical results are compared with simulated and reported experimental results, they are in close agreement.

  18. Analysis of Microstrip Line Fed Patch Antenna for Wireless Communications

    Science.gov (United States)

    Singh, Ashish; Aneesh, Mohammad; Kamakshi; Ansari, J. A.

    2017-11-01

    In this paper, theoretical analysis of microstrip line fed rectangular patch antenna loaded with parasitic element and split-ring resonator is presented. The proposed antenna shows that the dualband operation depends on gap between parasitic element, split-ring resonator, length and width of microstrip line. It is found that antenna resonates at two distinct resonating modes i.e., 0.9 GHz and 1.8 GHz for lower and upper resonance frequencies respectively. The antenna shows dual frequency nature with frequency ratio 2.0. The characteristics of microstrip line fed rectangular patch antenna loaded with parasitic element and split-ring resonator antenna is compared with other prototype microstrip line fed antennas. Further, the theoretical results are compared with simulated and reported experimental results, they are in close agreement.

  19. A Stacked Microstrip Antenna Array with Fractal Patches

    National Research Council Canada - National Science Library

    Xueyao Ren; Xing Chen; Yufeng Liu; Wei Jin; Kama Huang

    2014-01-01

      A novel microstrip antenna array, which utilizes Giuseppe Peano fractal shaped patches as its radiation elements and adopts a two-layer stacked structure for achieving both wideband and high-gain...

  20. Physically Connected Stacked Patch Antenna Design with 100% Bandwidth

    KAUST Repository

    Klionovski, Kirill

    2017-11-01

    Typically, stacked patch antennas are parasitically coupled and provide larger bandwidth than a single patch antenna. Here, we show a stacked patch antenna design where square patches with semi-circular cutouts are physically connected to each other. This arrangement provides 100% bandwidth from 23.9–72.2 GHz with consistent high gain (5 dBi or more) across the entire bandwidth. In another variation, a single patch loaded with a superstrate provides 83.5% bandwidth from 25.6–62.3 GHz. The mechanism of bandwidth enhancement is explained through electromagnetic simulations. Measured reflection coefficient, radiation patterns and gain results confirm the extremely wideband performance of the design.

  1. FDTD Analysis of U-Slot Rectangular Patch Antenna

    Science.gov (United States)

    Luk, K. M.; Tong, K. F.; Shum, S. M.; Lee, K. F.; Lee, R. Q.

    1997-01-01

    The U-slot rectangular patch antenna (Figure I) has been found experimentally to provide impedance and gain bandwidths of about 300 without the need of stacked or coplanar parasitic elements [1,2]. In this paper, simulation results of the U-slot patch using FDTD analysis are presented. Comparison with measured results are given.

  2. Wireless OAM transmission system based on elliptical microstrip patch antenna.

    Science.gov (United States)

    Chen, Jia Jia; Lu, Qian Nan; Dong, Fei Fei; Yang, Jing Jing; Huang, Ming

    2016-05-30

    The multiplexing transmission has always been a focus of attention for communication technology. In this paper, the radiation characteristics of circular microstrip patch antenna was firstly analyzed based on cavity model theory, and then spiral beams carrying orbital angular momentum (OAM) were generated, using elliptical microstrip patch antenna, with a single feed probe instead of a standard circular patch with two feedpoints. Moreover, by combining the proposed elliptic microstrip patch antenna with Universal Software Radio Peripheral (USRP), a wireless OAM transmission system was established and the real-time transmission of text, image and video in a real channel environment was realized. Since the wireless OAM transmission has the advantage of good safety and high spectrum utilization efficiency, this work has theoretical significance and potential application.

  3. IMPROVEMENT OF PARAMETERS OF STACKED MICROSTRIP PATCH ANTENNA USING EDGE COUPLED PARASITIC PATCHES AND METAMATERIAL SUPERSTRATE

    Directory of Open Access Journals (Sweden)

    Shridhar E. Mendhe

    2016-06-01

    Full Text Available High directive stacked multilayer and edge coupled planar microstrip patch antenna made from a single-layer helical resonating metamaterial superstrate has been investigated. Metamaterials are artificial materials whose properties not found in nature. These materials have negative permittivity and permeability and negative index of refraction over a frequency band. In this paper, an innovative design of stacked rectangular microstrip patch antenna using four edge coupled parasitic patches and helical resonating metamaterial superstrate is explored. The Rogers RO3003 material of dielectric constant 3 has been used as the substrate of the antenna. Investigation is carried out related to bandwidth, gain and directivity enhancement by using edge coupled patches and metamaterial superstrate also the study of highest reduction in the size of helical resonator is carried out and highest reduction in size of helical resonator is achieved at a metallic fill ratio of 0.2. The proposed antenna exhibits wide percentage bandwidth of approximately 72.62%.

  4. Design of Dual Band Microstrip Patch Antenna using Metamaterial

    Science.gov (United States)

    Rafiqul Islam, Md; Alsaleh Adel, A. A.; Mimi, Aminah W. N.; Yasmin, M. Sarah; Norun, Farihah A. M.

    2017-11-01

    Metamaterial has received great attention due to their novel electromagnetic properties. It consists of artificial metallic structures with negative permittivity (ɛ) and permeability (µ). The average cell size of metamaterial must be less than a quarter of wavelength, hence, size reduction for the metamaterial antenna is possible. In addition, metamaterial can be used to enhance the low gain and efficiency in conventional patch antenna, which is important in wireless communication. In this paper, dual band microstrip patch antenna design using metamaterial for mobile GSM and WiMax application is introduced. The antenna structure consists of microstrip feed line connected to a rectangular patch. An array of five split ring resonators (SRRs) unit cells is inserted under the patch. The presented antenna resonates at 1.8 GHz for mobile GSM and 2.4 GHz for WIMAX applications. The return loss in the FR4 antenna at 1.8 GHz is -22.5 dB. Using metamaterial the return loss has improved to -25 dB at 2.4 GHz and -23.5 dB at 1.8 GHz. A conventional microstrip patch antenna using pair of slots is also designed which resonates at 1.8 GHz and 2.4 GHz. The return loss at 1.8 GHz and 2.4 GHz were -12.1 dB and -21.8 dB respectively. The metamaterial antenna achieved results with major size reduction of 45%, better bandwidth and better returns loss if it is compared to the pair of slots antenna. The software used to design, simulate and optimize is CST microwave studio.

  5. Combined Calibration Method and its Realization for Direction Finding Antenna Systems with Patch Antennas

    Directory of Open Access Journals (Sweden)

    R. Seller

    2007-09-01

    Full Text Available A novel radio channel compensation method aiming to give optimal calibration for microstrip antenna array systems is presented in this paper, realized for an actual DOA measurement antenna system using microstrip antennas to sample the electromagnetic field, operating at 4.5GHz. This new approach considers mismatch between antennas and channel RF ports, channel transmission inequalities, and also decreases the effects of multipath propagation components of calibration reference signals by placing the calibration reference signal feeding network on the microstrip antenna array bearer, directly beside the antenna patches. It is combined with orthogonal spread spectrum calibration signal utility for continuous uninterrupted measurements. The spread spectrum calibration signal is orthogonal to the continuous wave (CW signal to be measured, therefore, the 2 signals can be separated in the receiver, enabling them to be present simultaneously. DOA measurement results are shown, measured with the realized integrated microstrip patch antenna array with calibration network hardware.

  6. Slot Coupled Patch Array Antenna Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed project is an antenna array whose beam is controlled digitally. The Phase 1 effort will assess the method needed to achieve the gain, bandwidth, and...

  7. Reconfigurable Wideband Circularly Polarized Microstrip Patch Antenna for Wireless Applications

    Science.gov (United States)

    Khidre, Ahmed

    In this thesis, developments of rectangular microstrip patch antenna to have circular polarization agility with wideband performance, for wireless applications are presented. First, a new technique to achieve circularly polarized (CP) probe feed single-layer microstrip patch antenna with wideband characteristics is proposed. The antenna is a modified form of the popular E-shaped patch, used to broaden the impedance bandwidth of a basic rectangular patch antenna. This is established by letting the two parallel slots of the E-patch unequal. Thus, by introducing asymmetry two orthogonal currents on the patch are excited and circularly polarized fields are realized. The proposed technique exhibits the advantage of the simplicity inherent in the E-shaped patch design. It requires only slot lengths, widths, and position parameters to be determined. Also, it is suitable for later adding the reconfigurable capability. With the aid of full-wave simulator Ansoft HFSS, investigations on the effect of various dimensions of the antenna have been carried out via parametric analysis. Based on these investigations, a design procedure for a CP E-shaped patch is summarized. Various design examples with different substrate thicknesses and material types are presented and compared, with CP U-slot patch antennas, recently proposed in the literature. A prototype has been constructed following the suggested design procedure to cover the IEEE 802.11b/g WLAN band. The performance of the fabricated antenna was measured and compared with the simulation results for the reflection coefficient, axial ratio, radiation pattern, and antenna gain. Good agreement is achieved between simulation and measured results demonstrating a high gain and wideband performance. Second, a polarization reconfigurable single feed E-shaped patch antenna with wideband performance is proposed. The antenna is capable of switching from right-hand circular polarization (RHCP) to left-hand circular polarization (LHCP) and

  8. Modified Microstrip Aperture Coupled Patch Antenna with Sierpinski Fractal Geometry

    Directory of Open Access Journals (Sweden)

    Hao Jiang

    2014-01-01

    Full Text Available A two-layer modified microstrip aperture coupled patch antenna with Sierpinski fractal geometry is presented in this paper. The effects of the two coupling slots and the parasitic patch are discussed. The proposed antenna can work on 956 MHz to 968 MHz, 3.654 GHz to 3.78 GHz, and 8.81 GHz to 9.28 GHz three frequency bands, and the maximum gain in each band is 4.64 dBi, 8.46 dBi, and 7.85 dBi, respectively. The simulated result reveals that the Sierpinski patch antenna we proposed in this paper performs better on radiation properties.

  9. Polyurethane membranes for flexible centimeter-wave patch antennas

    Science.gov (United States)

    Baron, Samuel; Guiffard, Benoit; Sharaiha, Ala

    2014-07-01

    In this paper, we present the original use of a recyclable and low cost soft polymer, polyurethane (PU) (ɛr ≈ 3.5 at 10 GHz), as part of a dielectric substrate of a microstrip patch antenna. The combination of simple membrane manufacturing process and the low Young’s modulus of PU (EPU ≈ 30 MPa) are employed in an X-band antenna application in this study. The PU dielectric characterizations indicate the high loss tangent value (tan δ ≈ 0.1 at 10 GHz). Membrane supported technology is used to reduce the influence of this high loss and increase the antenna efficiency. The measurement of antenna performances such as efficiency (η ≈ 31.7%) confirms the viability of the technological process and the specific patch antenna design developed in this work. Besides, the potential of the PU-based soft patch antenna for frequency agility (3.88%) via mechanical reconfiguration is also shown.

  10. Multi-band CRLH unit cell -loaded patch antenna

    Science.gov (United States)

    El-Henawy, Sally I.; Omar, Ahmed A.; Safwat, Amr M. E.; El-Hennawy, Hadia S.

    2017-01-01

    A multi-band patch antenna loaded with composite right-/left-handed (CRLH) unit cell is presented in this paper. It operates at three bands, which are not harmonically related, covering several communication standards. The first and third bands have patch-like radiation pattern, and the second band has monopole-like radiation pattern. These bands can be controlled by varying the patch size and unit cell element values. The performance was analyzed using both electromagnetic and circuit simulations; furthermore, measurements were taken and all were in good agreement.

  11. Microstrip Patch Antenna Bandwidth Enhancement Using AMC/EBG Structures

    Directory of Open Access Journals (Sweden)

    R. C. Hadarig

    2012-01-01

    Full Text Available A microstrip patch antenna with bandwidth enhancement by means of artificial magnetic conductor (AMC/electromagnetic band-gap structure (EGB is presented. The electrical characteristics of the embedded structure are evaluated using MoM simulations. The manufactured prototypes are characterized in terms of return loss, gain, and radiation pattern measurements in an anechoic chamber.

  12. Front-Side Microstrip Line Feeding a Raised Antenna Patch

    Science.gov (United States)

    Hodges, Richard; Hoppe, Daniel

    2005-01-01

    An improved design concept for a printed-circuit patch antenna and the transmission line that feeds the patch calls for (1) a microstrip transmission line on the front (radiative) side of a printed-circuit board based on a thin, high-permittivity dielectric substrate; (2) using the conductor covering the back side of the circuit board as a common ground plane for both the microstrip line and the antenna patch; (3) supporting the antenna patch in front of the circuit board on a much thicker, lower-permittivity dielectric spacer layer; and (4) connecting the microstrip transmission line to the patch by use of a thin wire or narrow ribbon that extends through the thickness of the spacer and is oriented perpendicularly to the circuit-board plane. The thickness of the substrate is typically chosen so that a microstrip transmission line of practical width has an impedance between 50 and 100 ohms. The advantages of this design concept are best understood in the context of the disadvantages of prior design concepts, as explained

  13. Ultra Wideband Slotted Microstrip Patch Antenna for Downlink and Uplink Satellite Application in C band

    OpenAIRE

    Tajeswita Gupta; P.K. Singhal

    2013-01-01

    An ultra-wideband slotted microstrip patch antenna has been proposed in this paper for uplink and downlink satellite applications in c band of IEEE 802.11 standards. Various slots have been introduced in the patch to achieve wider bandwidth. Presented work provides a comparative result of the microstrip patch antenna with and without the slots. Fractional bandwidth of the basic antenna is 9% which is increased to 46% after introduction of the slots in the proposed patch antenna.

  14. Cylindrical Bending of Deformable Textile Rectangular Patch Antennas

    Directory of Open Access Journals (Sweden)

    Freek Boeykens

    2012-01-01

    Full Text Available Textile patch antennas are well known as basic components for wearable systems that allow communication between a human body and the external world. Due to their flexibility, textile antennas are subjected to bending when worn, causing a variation in resonance frequency and radiation pattern with respect to the flat state in which their nominal design is performed. Hence, it is important for textile antenna engineers to be able to predict these performance parameters as a function of the bending radius. Therefore, we propose a comprehensive analytical model that extends the cylindrical cavity model for conformal rigid patch antennas by incorporating the effects of patch stretching and substrate compression. It allows to predict the resonance frequency and the radiation pattern as a function of the bending radius. Its validity has been verified experimentally. Unlike previous contributions, which concerned only qualitative studies by means of measurements and numerical full-wave simulations, the proposed model offers advantages in terms of physical insight, accuracy, speed, and cost.

  15. Study of LCP based flexible patch antenna array

    KAUST Repository

    Ghaffar, Farhan A.

    2012-07-01

    Wrapping of a two element LCP based patch antenna array is studied in this work. For the first time, the designed array is bent in both E and H planes to observe the effect on the radiation and impedance performance of the antenna. The 38 GHz simulation results reveal better performance for H plane bending as compared to E plane bending. A 100 um thick substrate is used for the design which is best suited for flexible antenna applications. Gain variations of 1.1 dB and 1.4 dB are observed for the two orientations while a significantly increased impedance bandwidth of 3 % is obtained with H plane wrapping. The design is highly suitable for broadband micro-cellular backhaul applications. © 2012 IEEE.

  16. A Fully Inkjet Printed 3D Honeycomb Inspired Patch Antenna

    KAUST Repository

    McKerricher, Garret

    2015-07-16

    The ability to inkjet print three-dimensional objects with integrated conductive metal provides many opportunities for fabrication of radio frequency electronics and electronics in general. Both a plastic material and silver conductor are deposited by inkjet printing in this work. This is the first demonstration of a fully 3D Multijet printing process with integrated polymer and metal. A 2.4 GHz patch antenna is successfully fabricated with good performance proving the viability of the process. The inkjet printed plastic surface is very smooth, with less than 100 nm root mean square roughness. The printed silver nanoparticles are laser sintered to achieve adequate conductivity of 1e6 S/m while keeping the process below 80oC and avoiding damage to the polymer. The antenna is designed with a honeycomb substrate which minimizes material consumption. This reduces the weight, dielectric constant and dielectric loss which are all around beneficial. The antenna is entirely inkjet printed including the ground plane conductor and achieves an impressive 81% efficiency. The honeycomb substrate weighs twenty times less than a solid substrate. For comparison the honeycomb antenna provides an efficiency nearly 15% greater than a similarly fabricated antenna with a solid substrate.

  17. Fine-Tuning on the Effective Patch Radius Expression of the Circular Microstrip Patch Antennas

    Directory of Open Access Journals (Sweden)

    A. E. Yilmaz

    2010-09-01

    Full Text Available In this study, the effective patch radius expression for the circular microstrip antennas is improved by means of several manipulations. Departing from previously proposed equations in the literature, one of the most accurate equations is picked up, and this equation is fine-tuned by means of Particle Swarm Optimization technique. Throughout the study, impacts of other parameters (such as the definition of the fitness/objective function, the degree-of-freedom in the proposed effective patch radius expression, the number of measured resonant frequency values are observed in a controlled manner. Finally, about 3% additional improvement is achieved over a very accurate formula, which was proposed earlier.

  18. Electromagnetic Wave Absorbing Technique Using Periodic Patterns for Low RCS Patch Array Antenna

    Science.gov (United States)

    Jang, Hong-Kyu; Lee, Yeon-Gwan; Shin, Jae-Hwan; Kim, Chun-Gon

    2013-07-01

    This paper presents an electromagnetic wave absorbing technique to reduce a radar cross-section (RCS) of a patch array antenna without compromising their antenna performance. The technique is based on periodic patterns, which is made of resistive materials. The 2×2 patch array antenna with a resonance frequency of 3.0 GHz was designed and fabricated. To reduce the RCS of the patch array antenna, the periodic patterns using a square patch element were proposed and applied to the surface between the four antenna patches. The printed lossy periodic patterns have radar absorbing performance at 12.0 GHz frequency. The measured results show that the lossy periodic patterns have no significant effect on the antenna radiation performance. On the other hand, the RCS is reduced by more than 98% compared to the conventional antenna at the target frequency.

  19. Innovative Double H Metamaterial Structure for Amelioration in Patch Antenna Parameters

    OpenAIRE

    Garg, Bimal; Saleem, Dauood

    2013-01-01

    A rectangular microstrip patch antenna along with a SSRR based “Double H” shaped metamaterial is proposed and analyzed at a height of 3.2mm from the ground plane. This work is mainly focused on increasing the potential parameters of microstrip patch antennas. The patch antenna along with the proposed metamaterial structure is designed to resonate at 1.84GHz. The impedance bandwidth of the patch antenna along with the proposed metamaterial structure is improved by 12.9MHz and return loss is re...

  20. Design and Fabrication of Graphene Reinforced Polymer Conductive Patch-Based Inset Fed Microstrip Antenna

    Science.gov (United States)

    Deepak, A.; Kannan, P. Muthu; Shankar, P.

    This work explores the design and fabrication of graphene reinforced polyvinylidene fluoride (PVDF) patch-based microstrip antenna. Primarily, antenna was designed at 6GHz frequency and simulation results were obtained using Ansoft HFSS tool. Later fabrication of antenna was carried out with graphene-PVDF films as conducting patch deposited on bakelite substrate and copper as ground plane. Graphene-PVDF films were prepared using solvent casting process. The radiation efficiency of fabricated microstrip patch antenna was 48% entailing it to be adapted as a practically functional antenna. Both simulated and the practical results were compared and analyzed.

  1. DESIGN AND CHARACTERIZATION OF E-SHAPE MICROSTRIP PATCH ANTENNA FOR WIRELESS COMMUNICATION

    Directory of Open Access Journals (Sweden)

    R. Divya

    2013-03-01

    Full Text Available The area of microstrip antennas has seen some inventive work in recent years and is one of the most dynamic fields of antenna theory. The ever increasing need for mobile communication and the emergence of newer technologies require an efficient design of antenna of smaller size for wider frequency range applications such as Wi-Max. The main aim of this paper is increase the impedance bandwidth of the microstrip patch antenna. A low profile wideband unequal E-shaped microstrip patch antenna for Wi-Max application is proposed in this paper .This proposed antenna is made by using the microstrip feeding method. Its bandwidth is further increased by introducing composite effect of stacking of patches with partial grounding. The antenna is designed and simulated by three-dimensional electromagnetic field software HFSS’12.The properties of the antenna such as bandwidth, S parameter, VSWR have been investigated.

  2. Mechanical Development of a Very Non-Standard Patch Array Antenna for Extreme Environments

    Science.gov (United States)

    Hughes, Richard; Chamberlain, Neil; Jakoboski, Julie; Petkov, Mihail

    2012-01-01

    This paper describes the mechanical development of patch antenna arrays for the Juno mission. The patch arrays are part of a six-frequency microwave radiometer instrument that will be used to measure thermal emissions from Jupiter. The very harsh environmental conditions in Jupiter orbit, as well as a demanding launch environment, resulted in a design that departs radically from conventional printed circuit patch antennas. The paper discusses the development and qualification of the Juno patch array antennas, with emphasis on the materials approach that was devised to mitigate the effects of electron charging in Jupiter orbit.

  3. Feedbacks between bivalve density, flow, and suspended sediment concentration on patch stable states.

    Science.gov (United States)

    Coco, Giovanni; Thrush, Simon F; Green, Malcolm O; Hewitt, Judi E

    2006-11-01

    We explore the role of biophysical feedbacks occurring at the patch scale (spatial scale of tens of meters) that influence bivalve physiological condition and affect patch stability by developing a numerical model for the pinnid bivalve, Atrina zelandica, in cohesive sediments. Simulated feedbacks involve bivalve density, flow conditions (assumed to be primarily influenced by local water depth and peak current speed), suspended sediment concentration (evaluated through a balance between background concentration, deposition, and erosion), and changes in the physiology of Atrina derived from empirical study. The model demonstrates that high bivalve density can lead to skimming flow and to a concomitant decrease in resuspension that will affect suspended sediment concentration over the patch directly feeding back on bivalve physiology. Consequently, for a given flow and background suspended sediment load, the stability of a patch directly depends on the size and density of bivalves in the patch. Although under a range of conditions patch stability is ensured independently of bivalve density, simulations clearly indicate that sudden changes in bivalve density or suspended sediment concentration can substantially affect patch structure and lead to different stable states. The model highlights the role of interactions between organisms, flow, and broader scale environmental conditions in providing a mechanistic explanation for the patchy occurrence of benthic suspension feeders.

  4. Thickness variation study of RFID-based folded patch antennas for strain sensing

    Science.gov (United States)

    Yi, Xiaohua; Wu, Terence; Lantz, Gabriel; Wang, Yang; Leon, Roberto T.; Tentzeris, Manos M.

    2011-04-01

    This paper explores folded patch antennas for the development of low-cost and wireless smart-skin sensors that monitor the strain in metallic structures. When the patch antenna is under strain/deformation, its resonance frequency varies accordingly. The variation can be easily interrogated and recorded by a wireless reader that also provides power for the antenna operation. The patch antenna adopts a specially selected substrate material with low dielectric constant, as well as an inexpensive off-the-shelf radiofrequency identification (RFID) chip for signal modulation. A thicker substrate increases RFID signal-to-noise ratio, but reduces the strain transfer efficiency. To experimentally study the effect of substrate thickness, two prototype folded patch antennas with different substrate thicknesses have been designed and manufactured. For both prototypes, tensile testing results show strong linearity between the interrogated resonance frequency and the strain experienced by the antenna. Longer interrogation range is achieved with the larger substrate thickness.

  5. Compact Shorted Stacked-Patch Antenna Integrated with Chip-Package Based on LTCC Technology

    OpenAIRE

    Li, Yongjiu; Li, Long; Dai, Xiwang; Zhu, Cheng; Huo, Feifei; Dong, Gang

    2014-01-01

    A low profile chip-package stacked-patch antenna is proposed by using low temperature cofired ceramic (LTCC) technology. The proposed antenna employs a stacked-patch to achieve two operating frequency bands and enhance the bandwidth. The height of the antenna is decreased to 4.09 mm (about λ/25 at 2.45 GHz) due to the shorted pin. The package is mounted on a 44 × 44 mm2 ground plane to miniaturize the volume of the system. The design parameters of the antenna and the effect of the antenna on ...

  6. Wideband Dual-Polarization Microstrip Patch Antenna Array for Airborne Ice Sounder

    DEFF Research Database (Denmark)

    Vazquez-Roy, Jose Luis; Krozer, Viktor; Dall, Jørgen

    2012-01-01

    We present the design and realization of an antenna array based on cavity-backed microstrip patch antenna elements, with a relative operating bandwidth exceeding 20% at a return-loss level better than 15 dB. The antenna array of four elements did not show any compromise in bandwidth. It exhibited...

  7. Dual band multi frequency rectangular patch microstrip antenna with flyswatter shaped slot for wireless systems

    Energy Technology Data Exchange (ETDEWEB)

    Bhardwaj, Dheeraj, E-mail: dbhardwaj.bit@gmail.com [Department of Physics, BIT-Mesra-Jaipur Campus, Jaipur 302017 (India); Saraswat, Shriti, E-mail: saraswat.srishti@gmail.com; Gulati, Gitansh, E-mail: gitanshgulati@gmail.com; Shekhar, Snehanshu, E-mail: snehanshushekhar.bit@gmail.com; Joshi, Kanika, E-mail: kanika.karesh@gmail.com [Department of Electronics & Communication, BIT-Mesra-Jaipur Campus, Jaipur 302017 (India); Sharma, Komal, E-mail: kbhardwaj18@gmail.com [Department of Physics, Swami Keshvanand Institute of Technology, Jaipur 302017 (India)

    2016-03-09

    In this paper a dual band planar antenna has been proposed for IEEE 802.16 Wi-MAX /IEEE 802.11 WLAN/4.9 GHz public safety applications. The antenna comprises a frequency bandwidth of 560MHz (3.37GHz-3.93GHz) for WLAN and WiMAX and 372MHz (4.82GHz-5.192GHz) for 4.9 GHz public safety applications and Radio astronomy services (4.8-4.94 GHz). The proposed antenna constitutes of a single microstrip patch reactively loaded with three identical steps positioned in a zig-zag manner towards the radiating edges of the patch. The coaxially fed patch antenna characteristics (radiation pattern, antenna gain, antenna directivity, current distribution, S{sub 11}) have been investigated. The antenna design is primarily focused on achieving a dual band operation.

  8. Optimization of a Circularly Polarized Patch Antenna for Two Frequency Bands

    Science.gov (United States)

    2015-09-01

    2.2 Patch Rogers 6010 14 3. Results and Discussion 20 4. Future Work 20 5. References 23 Distribution List 26 iv List of Figures Fig. 1...ARL-TR-7462 ● SEP 2015 US Army Research Laboratory Optimization of a Circularly Polarized Patch Antenna for Two Frequency Bands...Circularly Polarized Patch Antenna for Two Frequency Bands by Jahin S Habib Sensors and Electron Devices Directorate, ARL

  9. Left-Handed Effect of Composite Rectangular SRRs and Its Application in Patch Antennae

    Science.gov (United States)

    Huang, Ming; Zhou, Yue-Qun; Shen, Ting-Gen

    2010-01-01

    We concentrate on describing the important influence and physical law of the split resonant ring (SRR) based left-handed materials on patch antennae. The finite-difference time-domain method, together with the finite element method is used to study the characteristics of patch antennae based on composite rectangular SRRs. A novel composite rectangular SRR system is formed by assembling the conventional patch antennae and SRRs, it is found that electromagnetic wave resonance occurs near f = 3.15 GHz, the equivalent permittivity and permeability are both negative, and the electromagnetic wave's tunnel effect and evanescent waves' enhancing effect are formed, which can improve the localization extent of electromagnetic wave's energy apparently. Such effects can improve the antenna's radiation gain and its matching condition. The phenomenon indicates that such composite rectangular patch antennae are promising in wireless communications such as mobile phones, satellite communication and aviation.

  10. Planar dielectric resonator stabilized HEMT oscillator integrated with CPW/aperture coupled patch antenna

    Science.gov (United States)

    Simons, Rainee N.; Lee, Richard Q.

    1992-01-01

    A design of an active antenna with a dielectric resonator stabilized high-electron-mobility transistor (HEMT) oscillator (DRO) and an aperture-coupled patch antenna is reported. The circuit is fabricated using coplanar waveguide (CPW) with the oscillator and the antenna on opposite sides of the substrate. The active antenna was demonstrated at 7.6 GHz; however, the design can be scaled to higher frequencies. Excellent oscillator characteristics and radiation patterns were obtained.

  11. Conformal Patch Antenna Arrays Design for Onboard Ship Deployment Using Genetic Algorithms

    Directory of Open Access Journals (Sweden)

    Stelios A. Mitilineos

    2013-01-01

    Full Text Available Conformal antennas and antenna arrays (arrays have become necessary for vehicular communications where a high degree of aerodynamic drag reduction is needed, like in avionics and ships. However, the necessity to conform to a predefined shape (e.g., of an aircraft’s nose directly affects antenna performance since it imposes strict constraints to the antenna array’s shape, element spacing, relative signal phase, and so forth. Thereupon, it is necessary to investigate counterintuitive and arbitrary antenna shapes in order to compensate for these constraints. Since there does not exist any available theoretical frame for designing and developing arbitrary-shape antennas in a straightforward manner, we have developed a platform combining a genetic algorithm-based design, optimization suite, and an electromagnetic simulator for designing patch antennas with a shape that is not a priori known (the genetic algorithm optimizes the shape of the patch antenna. The proposed platform is further enhanced by the ability to design and optimize antenna arrays and is intended to be used for the design of a series of antennas including conformal antennas for shipping applications. The flexibility and performance of the proposed platform are demonstrated herein via the design of a high-performance GPS patch antenna.

  12. Effects of Reentry Plasma Sheath on GPS Patch Antenna Polarization Property

    Directory of Open Access Journals (Sweden)

    L. Zhao

    2013-01-01

    Full Text Available A plasma sheath enveloping a reentry vehicle would affect performances of on-board antenna greatly, especially the navigation antennas. This paper studies the effects of reentry plasma sheath on a GPS right-hand circularly polarized (RHCP patch antenna polarization property during a typical reentry process. Utilizing the algorithm of finite integration technique, the polarization characteristic of a GPS antenna coated by a plasma sheath is obtained. Results show that the GPS RHCP patch antenna radiation pattern distortions as well as polarization deteriorations exist during the entire reentry process, and the worst polarization mismatch loss between a GPS antenna and RHCP GPS signal is nearly 3 dB. This paper also indicates that measures should be taken to alleviate the plasma sheath for maintaining the GPS communication during the reentry process.

  13. High Gain Patch Antenna with Composite Right-Left Handed Structure and Dendritic Cell Metamaterials

    Science.gov (United States)

    Liu, Yahong; Zhao, Xiaopeng

    2010-04-01

    We present a novel high-gain patch antenna utilizing composite right-left handed (CRLH) structure and dendritic cell metamaterials. The proposed CRLH antenna, composed of modified Sievenpiper mushroom unit-cells, is based on the positive first-order resonance mode for high gain. In addition, the dendritic cell metamaterials are used to surround the proposed antenna to further increase the antenna directivity and gain due to suppressing the surface waves. The experimental results show that the gain and the directivity of the proposed antenna with CRLH and dendritic cells can be improved by 3.88 dB and 8.82, respectively, in comparison with a conventional patch antenna. Moreover, a 10-dB bandwidth with 9.55% is achieved. The measured results are in good agreement with the simulated ones.

  14. Dual-band microstrip patch antenna based on metamaterial refractive surface

    Science.gov (United States)

    Salhi, Ridha; Labidi, Mondher; Boujemaa, Mohamed Ali; Choubani, Fethi

    2017-06-01

    In this paper, we present a new design of microstrip patch antenna based on metamaterial refractive surface (MRS). By optimizing the air gap between the MRS layer and the patch antenna to be 7 mm, the band width and the gain of the proposed antenna are significantly enhanced. The proposed prototype presents a dual band antenna. The center frequency for the first band is 2.44 GHz and the generated bandwidth is 25 MHz. The second band has a center frequency of 2.8 GHz and with a bandwidth of 50 MHz. The simulation results are analyzed and discussed in terms of return loss, gain and radiation pattern using electromagnetic simulator software. Finally, the designed dual band antenna is fabricated and different measurement results are performed and compared with simulation results in order to validate its performances. The proposed antenna supports WiBro (wireless broadband), ISM, WiFi, Bluetooth, WiMAX and radars services.

  15. Stacked-patch antenna with switchable propagating mode for UHF body-centric communications

    NARCIS (Netherlands)

    Scanlon, W.G.; Chandran, A.R.

    2009-01-01

    The ability to electronically switch between off-body and on-body communications is a useful feature for wearable antenna applications. Therefore, we present a novel stacked-patch antenna with a switched propagation mode for body-centric communications at 2.45 GHz. Mounted 2 mm above a muscle-tissue

  16. Analysis of photonic crystal and multi-frequency terahertz microstrip patch antenna

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lechen, E-mail: yanglechen@163.com [The 41st Research Institute of CETC, Qingdao 266555, Shandong Province (China); Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, Jiangsu Province (China); Key Laboratory of Nanodevices and Applications, Chinese Academy of Science, Suzhou 215123, Jiangsu Province (China); Shi, Xueshun [The 41st Research Institute of CETC, Qingdao 266555, Shandong Province (China); Science and Technology on Electronic Test and Measurement Laboratory, Qingdao 266555, Shandong Province (China); Chen, Kunfeng [The 41st Research Institute of CETC, Qingdao 266555, Shandong Province (China); Fu, Kai; Zhang, Baoshun [Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, Jiangsu Province (China); Key Laboratory of Nanodevices and Applications, Chinese Academy of Science, Suzhou 215123, Jiangsu Province (China)

    2013-12-15

    In this paper, two-dimensional photonic crystals working at terahertz (THz) frequency is analyzed, a multi-frequency terahertz microstrip patch antenna on photonic crystal substrate is presented and its electromagnetic wave propagation phenomenon is investigated. The proposed antenna can work at five frequency points' scope at terahertz frequency regions, and the radiation efficiency is as high as ∼96%. The photonic crystal structure of the substrate is used to enhance the gain, directivity and radiation efficiency of the antenna.

  17. A New Fractal-Based Miniaturized Dual Band Patch Antenna for RF Energy Harvesting

    Directory of Open Access Journals (Sweden)

    Sika Shrestha

    2014-01-01

    Full Text Available The growth of wireless communications in recent years has made it necessary to develop compact, lightweight multiband antennas. Compact antennas can achieve the same performance as large antennas do with low price and with greater system integration. Dual-frequency microstrip antennas for transmission and reception represent promising approach for doubling the system capacity. In this work, a miniaturized dual band antenna operable at 2.45 and 5.8 GHz is constructed by modifying the standard microstrip patch antenna geometry into a fractal structure. In addition to miniaturization and dual band nature, the proposed antenna also removes unwanted harmonics without the use of additional filter component. Using a finite-element-method-based high frequency structure simulator (HFSS, the antenna is designed and its performance in terms of return loss, impedance matching, radiation pattern, and voltage standing wave ratio (VSWR is demonstrated. Simulation results are shown to be in close agreement with performance measurements from an actual antenna fabricated on an FR4 substrate. The proposed antenna can be integrated with a rectifier circuit to develop a compact rectenna that can harvest RF energy in both of these frequency bands at a reduction in size of 25.98% relative to a conventional rectangular patch antenna.

  18. Comparative Study of Microstrip Patch Antenna Feed Network (PREPRINT)

    Science.gov (United States)

    2014-10-09

    etch processed along with the patch itself thus reducing manufacturing cost. Edge fed patches can be easily fabricated and simplicity in modelling...width of the patch is adjusted to give an input impedance that would facilitate the fabrication using a CNC milling machine with minimum allowable

  19. Patch Antenna based on a Photovoltaic Cell with a Dual resonance Frequency

    Directory of Open Access Journals (Sweden)

    C. Baccouch

    2016-11-01

    Full Text Available The present work was to use photovoltaic solar cells in patch antenna structures. The radiating patch element of a patch antenna was replaced by a solar cell. Direct Current (DC generation remained the original feature of the solar cell, but additionally   it was now able to receive and transmit electromagnetic waves. Here, we used a new patch antenna structure based on a photovoltaic solar cell. It was then used to collect photo-generated current as well as Radio Frequency (RF transmission. A mathematical model which would serve the minimization of power losses of the cell and therefore the improvement in the conversion efficiency was studied. A simulation allowed analysing the performance of the antenna, with a silicon material, and testing its parameters such as the reflection coefficient (S11, gain, directivity and radiated power. The performance analysis of the solar cell patch antenna was conducted using Advanced Design System (ADS software. Simulation results for this antenna showed a dual resonance frequency of 5.77 GHz and of 6.18 GHz with an effective return loss of -38.22dB and a gain of 1.59dBi.

  20. Design and analysis of tip slotted square patch nano-antenna

    Science.gov (United States)

    Sharma, Shubhanshi; Shankhwar, Nishant; Kalra, Yogita; Sinha, Ravindra Kumar

    2017-08-01

    In this paper, study of novel design of gold tip slotted square patch nanoantenna placed over silica substrate has been done. Designed antenna is optimised on basis of various geometrical parameters such as antenna length, thickness, gap between the antenna etc. using COMSOL Multiphysics a finite element method (FEM) based simulation software for the near field analysis. Both single and coupled tip slotted square patch antenna are analysed and the effect of slot on the antenna performance is also studied. The operational wavelength is in the near and mid infrared range of the electromagnetic (EM) spectrum as nanoantenna finds various applications in the field of near field microscopy, spectroscopy, infrared(IR) detection, waste energy and solar energy harvesting.

  1. A Butterfly-Shaped Wideband Microstrip Patch Antenna for Wireless Communication

    Directory of Open Access Journals (Sweden)

    Liling Sun

    2015-01-01

    Full Text Available A novel butterfly-shaped patch antenna for wireless communication is introduced in this paper. The antenna is designed for wideband wireless communications and radio-frequency identification (RFID systems. Two symmetrical quasi-circular arms and two symmetrical round holes are incorporated into the patch of a microstrip antenna to expand its bandwidth. The diameter and position of the circular slots are optimized to achieve a wide bandwidth. The validity of the design concept is demonstrated by means of a prototype having a bandwidth of about 40.1%. The return loss of the butterfly-shaped antenna is greater than 10 dB between 4.15 and 6.36 GHz. The antenna can serve simultaneously most of the modern wireless communication standards.

  2. Design and Analysis of Ultra-wideband Micro Strip Patch Antenna with Notch Band Characteristics

    Directory of Open Access Journals (Sweden)

    Kumar Omprakash

    2016-01-01

    Full Text Available A new design of ultra-wideband (UWB micro strip patch antenna with notch band characteristic for wireless local area network (WLAN application is presented in this paper. The proposed antenna consists of a rectangular patch with a partial ground plane that is fed by 50 Ω micro strip line. A notch band function is created by inserting overlapped one U-shape and one C-shape slot on the radiator patch, added additional patch to the ground plane side and slit in truncated ground plane. The proposed antenna potentially minimized frequency interference between WLAN and UWB system. This antenna with the size of 26 mm × 32 mm (W×L and the simulated results show that the antenna can operate over the frequency band between 3.1 and 10.45 GHz for voltage standing wave ratio (VSWR > 2 with band notch 5.06-5.825 GHz. Besides in the working band, the antenna shows good radiation pattern in the H-plane and the E-plane and has good time domain characteristic.

  3. Frequency Reconfigurable Circular Patch Antenna with an Arc-Shaped Slot Ground Controlled by PIN Diodes

    Directory of Open Access Journals (Sweden)

    Yao Chen

    2017-01-01

    Full Text Available In this paper, a compact frequency reconfigurable circular patch antenna with an arc-shaped slot loaded in the ground layer is proposed for multiband wireless communication applications. By controlling the ON/OFF states of the five PIN diodes mounted on the arc-shaped slot, the effective length of the arc-shaped slot and the effective length of antennas current are changed, and accordingly six-frequency band reconfiguration can be achieved. The simulated and measured results show that the antenna can operate from 1.82 GHz to 2.46 GHz, which is located in DCS1800 (1.71–1.88 GHz, UMTS (2.11–2.20 GHz, WiBro (2.3–2.4 GHz, and Bluetooth (2.4–2.48 GHz frequency bands and so forth. Compared to the common rectangular slot circular patch antenna, the proposed arc-shaped slot circular patch antenna not only has a better rotational symmetry with the circular patch and substrate but also has more compact size. For the given operating frequency at 1.82 GHz, over 55% area reduction is achieved in this design with respect to the common design with rectangular slot. Since the promising frequency reconfiguration, this antenna may have potential applications in modern multiband and multifunctional mobile communication systems.

  4. DESIGN OF MULTILAYER APERTURE COUPLED STACKED MICROSTRIP PATCH ANTENNA FOR WLAN APPLICATIONS

    Directory of Open Access Journals (Sweden)

    P. Jothilakshmi

    2015-10-01

    Full Text Available One of the major drawbacks of microstrip patch antenna is its narrow bandwidth. The solution of this problem is to use aperture coupled stacked micro strip patch antenna. The antenna uses a combination of aperture coupled feeding technique and multi- layer radiating patch in order for the radiating elements are increase the gain bandwidth. The ‘I’ and ‘H’ shaped aperture slots are etched onto the ground plane. It is used to transfer the energy from feed line to stacked patch. A variation of the feed line length controls the selected aperture slots to be active. The waves from the selected activated aperture slots will radiate to particular radiating patch and achieve the desired resonant frequency. The air gap is used to avoid coupling loss between the aperture slots and stacked patches. The observed simulated and measured results show that the proposed antenna structure resonated at 2.51 GHz frequency with reduced return loss and optimum voltage standing wave ratio.

  5. Design and Development of Compact Microstrip Patch Antenna for Wireless Applications

    Directory of Open Access Journals (Sweden)

    R. Nagendra

    2017-09-01

    Full Text Available In this paper, a novel dual band microstrip patch antenna based on composite patch antenna and radiating part. By selecting a suitable offset feed position, it is feasible to provide 50Ω characteristic impedance and thus making better impedance matching. The proposed antenna has been improved broader bandwidth by using RT Duroid substrate. The radiating part is plays a important role in creating a lower operating band (2.45 GHz in addition to achieve miniaturization. The proposed antenna has to be fabricated with RT / Duroid substrate and dimensions of 19 × 22 × 0.8 mm. The measured -10 dB bandwidth of 200 MHz at 2.45 GHz and 990 MHz at 5.45 GHz, which is quite useful for Industrial, Scientific and Medical (ISM and WLAN applications.

  6. Design and characterization of a tunable patch antenna loaded with capacitive MEMS switch using CSRRs structure on the patch

    Directory of Open Access Journals (Sweden)

    Rajesh Saha

    2016-09-01

    Full Text Available In this paper, the design and characterization of a tunable patch antenna loaded with complementary split ring resonators (CSRRs on the patch have been realized. To achieve tunable resonant frequency, bandwidth and radiation pattern, the antenna is further loaded with coplanar waveguide (CPW on which Microelectromechanical System (MEMS capacitive switches are placed periodically. The tunable property is achieved, when the switches moves from up state with the capacitive gap 1.5 μm to down state having capacitive gap of 1 μm. A parametric analysis has been presented to check the sensitivity of the antenna in terms of S11 parameter by varying different parameters of the MEMS switches and CSRRs. This work, strives to improve the degree of reconfigurability with increase in the number of switches. The value of actuation voltage to move switch from up to down state is 10.4 V, which is very low over the other design. The switches exhibit fundamental frequency 14.6 kHz, switching time 28.59 μs, and capacitance ratio 15.27. Simulation has been carried out in Ansoft HFSS v. 13 and the distinct characterization property of the tunable antenna is shown through simulation.

  7. A Compact Multiband Metamaterial based Microstrip Patch Antenna for Wireless communication Applications

    OpenAIRE

    Nikhil Kulkarni; G. B. Lohiya

    2017-01-01

    In this paper, a metamaterial based compact multiband microstrip antenna is proposed which can give high gain and directivity. Metamaterials are periodic structures and have been intensively investigated due to the particular features such as ultra-refraction phenomenon and negative permittivity and/or permeability. A metamaterialbased microstrip patch antenna with enhanced characteristics and multi band operation will be investigated in this work. The multiple frequency operation will be ach...

  8. Wave Concept Iterative Procedure Analysis of Patch Antennas on Nanostructured Ceramic Substrates

    Directory of Open Access Journals (Sweden)

    V. Silva Neto

    2014-02-01

    Full Text Available The wave concept iterative procedure (WCIP is proposed to analyze rectangular and circular patch antennas on nanostructured ceramic substrates. Principles of WCIP are described and advantages are emphasized. The analysis of microstrip antennas on double layered substrates is performed in space and spectral domains. In addition, Fast Fourier Transformation (FFT is used to improve the efficiency of the method. WCIP simulated results are compared to HFSS software ones. A good agreement is observed.

  9. Novel Dual Band Microstrip Circular Patch Antennas Loaded with ENG and MNG Metamaterials

    Directory of Open Access Journals (Sweden)

    Md. Ababil Hossain

    2014-01-01

    Full Text Available Novel design of a dual band microstrip circular patch antenna loaded with ENG (ε negative metamaterial has been shown in the first section. Using ENG metamaterial instead of the conventional dielectric, unconventional TMδ10 (1<δ<2 mode was produced to yield a dual band performance. Optimized parameters such as permittivity (ε1 and filling ratio (η of metamaterials were selected with the aid of a MATLAB based parameter optimization algorithm, developed for all these sort of patch antennas. In the second section, a dual band circular patch antenna loaded with MNG (µ negative metamaterial has been reported. An unconventional modified TMδ10 (0<δ<1 mode has been produced along with conventional TM110 mode due to using MNG metamaterial. Here also the optimum values of permeability (µ1 and filling ratio (η for these sorts of patch antennas have been calculated from a MATLAB based parameter optimization algorithm. Both the proposed antennas provide good and resonance and satisfactory radiation performances (directivity, radiation efficiency, and gain with a dual band performance.

  10. Broadband Semielliptical Patch Antenna with Semicircular Ring Slot for WiMax Application

    Directory of Open Access Journals (Sweden)

    Brajraj Shrama

    2014-01-01

    Full Text Available This paper reports the design and analysis of a semielliptical patch antenna modified by cutting semicircular ring slot in patch geometry and obtained results are discussed. The reported antenna is designed on a multilayered substrate material having two glass epoxy FR-4 substrates separated by a thin foam substrate having thickness 1.0 mm. The size of ground plane is 75 mm×75 mm, whereas the patch dimension along major and minor axes is 23.0 mm and 14.0 mm, respectively. The two modes corresponding to resonance frequencies 3.39 GHz and 3.73 GHz are excited to provide wide impedance bandwidth 21.1% with respect to central frequency with stable radiation patterns. The antenna shows circular polarization with axial ratio bandwidth 5.5% and minimum axial ratio value 1.65 dBi. The radiation patterns of proposed antenna are normal to the surface of patch and are almost identical in shape as required for practical applications. The proposed antenna covers entire median band of WiMax communication systems ranges from 3.40 GHz to 3.6 GHz.

  11. Understanding and optimizing microstrip patch antenna cross polarization radiation on element level for demanding phased array antennas in weather radar applications

    Science.gov (United States)

    Vollbracht, D.

    2015-11-01

    The antenna cross polarization suppression (CPS) is of significant importance for the accurate calculation of polarimetric weather radar moments. State-of-the-art reflector antennas fulfill these requirements, but phased array antennas are changing their CPS during the main beam shift, off-broadside direction. Since the cross polarization (x-pol) of the array pattern is affected by the x-pol element factor, the single antenna element should be designed for maximum CPS, not only at broadside, but also for the complete angular electronic scan (e-scan) range of the phased array antenna main beam positions. Different methods for reducing the x-pol radiation from microstrip patch antenna elements, available from literature sources, are discussed and summarized. The potential x-pol sources from probe fed microstrip patch antennas are investigated. Due to the lack of literature references, circular and square shaped X-Band radiators are compared in their x-pol performance and the microstrip patch antenna size variation was analyzed for improved x-pol pattern. Furthermore, the most promising technique for the reduction of x-pol radiation, namely "differential feeding with two RF signals 180° out of phase", is compared to single fed patch antennas and thoroughly investigated for phased array applications with simulation results from CST MICROWAVE STUDIO (CST MWS). A new explanation for the excellent port isolation of dual linear polarized and differential fed patch antennas is given graphically. The antenna radiation pattern from single fed and differential fed microstrip patch antennas are analyzed and the shapes of the x-pol patterns are discussed with the well-known cavity model. Moreover, two new visual based electromagnetic approaches for the explanation of the x-pol generation will be given: the field line approach and the surface current distribution approach provide new insight in understanding the generation of x-pol component in microstrip patch antenna radiation

  12. Pattern Reconfigurable Patch Antenna menggunakan Edge Shorting Pin dan Symmetrical Control Pin

    Directory of Open Access Journals (Sweden)

    DWI ANDI NURMANTRIS

    2016-02-01

    Full Text Available Abstrak Metode baru dalam mendesain suatu pattern reconfigurable antenna telah diteliti. Penelitian ini fokus pada optimasi antena patch lingkaran single layer pencatuan probe koaksial dengan mengintegrasikan 24 switch/shorting pin pada sisi patch yang disebut edge shorting pin dan 8 shorting pin membentuk lingkaran dengan radius tertentu dan selanjutnya disebut symmetrical control pin yang fungsinya sebagai metode penyepadan impedansi. Algoritma Genetika yang dikombinasikan dengan Finite Element Software digunakan untuk mengoptimasi kombinasi  switch, radius lingkaran symmetrical control pin, dan radius patch untuk mendapatkan kemampuan pattern reconfigurability. Antena ini menghasilkan 8 kemungkinan arah radiasi azzimuth dengan resolusi 45o dan arah elevasi 30o pada frekuensi 2,4 Ghz. Optimasi, simulasi, fabrikasi, dan pengukuran dilakukan untuk memverifikasi hasil penelitian. Kata kunci: Patch Lingkaran, Edge Shorting Pin, Symmetrical Control Pin, Algoritma Genetika, Pattern Reconfigurable   Abstract New method for desaining pattern reconfigurable antenna was studied. This study focuses on the optimization of a single layer circular patch antenna with probe feed by integrating the 24 switch / shorting pin on the side of the patch that called Edge Shorting Pins and 8 shorting pins form circular line in such radius that called Symmetrical Control Pins as a impedance matching method. Genetic algorithm combined with the Finite Element Software is used to optimize the switch combination, the radius of circular line of symmetrical control pins, and the patch radius to obtain a pattern reconfigurability capabilities. This antenna produces 8 possible directions of azimuth radiation with a resolution of 45o and 30o elevation direction at a frequency of 2.4 GHz. Optimization, simulation, fabrication, and measurement was done to verify the results. Keywords: Circular Patch, Edge Shorting Pin, Symmetrical Control Pin, Genetic Algorithm, Pattern

  13. Microwave sensor for tangerine classification based on coupled-patch antennas

    Science.gov (United States)

    Leekul, Prapan; Chivapreecha, Sorawat; Krairiksh, Monai

    2016-08-01

    This paper deals with a microwave sensor for classifying tangerines by flavour using coupled-patch antennas. The operating frequency of the antennas is 2.45 GHz. The sensor determines the flavour of each tangerine by measuring the magnitudes of coupled signals of the antennas with the tangerine fruit at the centre. The sorting is carried out using an artificial neural network implemented on a field programmable gate array. The classification performance of the sensor is 95% accurate, so it has potential for use in sorting tangerines by flavour. In addition, the system uncertainty is analysed to determine optimal operating conditions.

  14. Tri Band Dual Polarized Patch Antenna System For Next Generation Cellular Networks

    Directory of Open Access Journals (Sweden)

    Syed Daniyal Ali Shah

    2017-12-01

    Full Text Available In fifth generation networks much emphasis is given to reduce the handset and base station sizes while incorporating even more features for ubiquitous connectivity. Polarization diversity is one of the methods in which a single multi-polarized antenna brings the advantages of antenna diversity. The multiband handset antennas can be made dual-polarized for improved compensation of fading effects of propagation environment especially in terrestrial bands. This paper focuses on the outcomes of the development of a horizontal and vertical polarized patch antenna scheme that operates on 3 bands 900 MHz 1.8 GHz and 2.4 GHz. The antenna system is tested for gain directivity reflection loss polarization radiation pattern and other parameters. The results are published and found are found to satisfy the requirements of cellular and data communication networks in the specified bands.

  15. A Comparison Between Jerusalem Cross and Square Patch Frequency Selective Surfaces for Low Profile Antenna Applications

    Science.gov (United States)

    Cure, David; Weller, Thomas; Miranda, Felix A.

    2011-01-01

    In this paper, a comparison between Jerusalem Cross (JC) and Square Patch (SP) based Frequency Selected Surfaces (FSS) for low profile antenna applications is presented. The comparison is aimed at understanding the performance of low profile antennas backed by high impedance surfaces. In particular, an end loaded planar open sleeve dipole (ELPOSD) antenna is examined due to the various parameters within its configuration, offering significant design flexibility and a wide operating bandwidth. Measured data of the antennas demonstrate that increasing the number of unit cells improves the fractional bandwidth. The antenna bandwidth increased from 0.8% to 1.8% and from 0.8% to 2.7% for the JC and SP structures, respectively. The number of unit cells was increased from 48 to 80 for the JC-FSS and from 24 to 48 for the SP-FSS.

  16. A CSRR-Fed SIW Cavity-Backed Fractal Patch Antenna for Wireless Energy Harvesting and Communication.

    Science.gov (United States)

    Cao, Hailin; Jiang, Fen; Liu, Jiujiu; Cai, Wenbin; Tang, Mingchun; Tan, Xiaoheng; Yang, Shizhong

    2015-08-28

    This paper presents a novel compact dual-band and dual-polarized complementary split-ring resonator (CSRR)-fed substrate-integrated waveguide (SIW) cavity-backed fractal patch antenna for wireless energy harvesting and communication. The proposed antenna is composed of a Giuseppe Peano fractal radiation patch with a backed SIW cavity. To enhance the bandwidth and minimize the dimensions, the CSRR structure is designed to feed the Giuseppe Peano fractal patch orthogonally. A prototype of the proposed antenna is simulated, fabricated and measured. The proposed antenna exhibits good directionality and high cross-polarization level with especially compact size.

  17. A CSRR-Fed SIW Cavity-Backed Fractal Patch Antenna for Wireless Energy Harvesting and Communication

    Directory of Open Access Journals (Sweden)

    Hailin Cao

    2015-08-01

    Full Text Available This paper presents a novel compact dual-band and dual-polarized complementary split-ring resonator (CSRR-fed substrate-integrated waveguide (SIW cavity-backed fractal patch antenna for wireless energy harvesting and communication. The proposed antenna is composed of a Giuseppe Peano fractal radiation patch with a backed SIW cavity. To enhance the bandwidth and minimize the dimensions, the CSRR structure is designed to feed the Giuseppe Peano fractal patch orthogonally. A prototype of the proposed antenna is simulated, fabricated and measured. The proposed antenna exhibits good directionality and high cross-polarization level with especially compact size.

  18. High-efficiency dual-polarized patch antenna array with common waveguide feed

    OpenAIRE

    Vilaltella Esteve, Robert

    2013-01-01

    Treball realitzat a l'Institut für Hochfrequenztechnik (IHF)de la Universität Stuttgart [ANGLÈS] A concept for a dual-polarized patch antenna array with large bandwidth and high efficiency is proposed. A short overmoded waveguide section is connected to a square feed waveguide on one side, and to the common groundplane of a 2x2 or a 3x3 patch array on the other side. Each square-shaped patch is coupled to the waveguide by crossed slots in the groundplane. The coupled resonances of the patc...

  19. Probe-Fed Stacked Microstrip Patch Antenna for High-Resolution Polarimetric C-Band SAR

    DEFF Research Database (Denmark)

    Granholm, Johan; Skou, Niels

    2000-01-01

    The paper describes a C-band, dual-linear polarization wideband antenna for use in the next-generation of the Danish high-resolution, airborne polarimetric synthetic aperture radar (SAR) system, EMISAR. The design and performance of a probe-fed, stacked microstrip patch element, operating from 4...

  20. Broadbanding of circularly polarized patch antenna by waveguided magneto-dielectric metamaterial

    Directory of Open Access Journals (Sweden)

    Xin Mi Yang

    2015-12-01

    Full Text Available Design of bandwidth-enhanced circularly polarized (CP patch antenna using artificial magneto-dielectric substrate was investigated. The artificial magneto-dielectric material adopted here takes the form of waveguided metamaterial (WG-MTM. In particular, the embedded meander line (EML structure was employed as the building element of the WG-MTM. As verified by the retrieved effective medium parameters, the EML-based waveguided magneto-dielectric metamaterial (WG-MDM exhibits two-dimensionally isotropic magneto-dielectric property with respect to TEM wave excitations applied in two orthogonal directions. A CP patch antenna loaded with the EML-based WG-MDM (WG-MDM antenna has been proposed and its design procedure is described in detail. Simulation results show that the impedance and axial ratio bandwidths of the WG-MDM antenna have increased by 125% and 133%, respectively, compared with those obtained with pure dielectric substrate offering the same patch size. The design of the novel WG-MDM antenna was also validated by measurement results, which show good agreement with their simulated counterparts.

  1. Design, Analysis, and Verification of Ka-Band Pattern Reconfigurable Patch Antenna Using RF MEMS Switches

    Directory of Open Access Journals (Sweden)

    Zhongliang Deng

    2016-08-01

    Full Text Available This paper proposes a radiating pattern reconfigurable antenna by employing RF Micro-electromechanical Systems (RF MEMS switches. The antenna has a low profile and small size of 4 mm × 5 mm × 0.4 mm, and mainly consists of one main patch, two assistant patches, and two RF MEMS switches. By changing the RF MEMS switches operating modes, the proposed antenna can switch among three radiating patterns (with main lobe directions of approximately −17.0°, 0° and +17.0° at 35 GHz. The far-field vector addition model is applied to analyse the pattern. Comparing the measured results with analytical and simulated results, good agreements are obtained.

  2. 2×1 Microstrip Patch Array Antenna with Harmonic Suppression Capability for Rectenna

    Directory of Open Access Journals (Sweden)

    Nur Aisyah Amir

    2017-12-01

    Full Text Available This paper is an extension of work originally presented in 2016 IEEE Asia-Pacific Conference on Applied Electromagnetics (APACE. A 2×1 microstrip patch array antenna integrated with photonic bandgap (PBG and stubs is designed and analyzed. The performance of the PBG and stubs structure are explained and analyzed in terms of the elimination of the resonance at the harmonic frequencies of the antenna. The proposed antenna is designed on FR-4 substrate with thickness of 1.6 mm and operated at 2.45 GHz frequency suitable for rectenna design application. From the simulated result, the first harmonic frequency (5.4 GHz, the second harmonic frequency (6.6 GHz and the third harmonic frequency (7.8 GHz are successfully suppressed. For instance, the radiation to the forward of the stubs-PBG antenna is suppressed at more than 15 dB at the second and third harmonic frequencies.

  3. Analysis of single band and dual band graphene based patch antenna for terahertz region

    Science.gov (United States)

    George, Jemima Nissiyah; Madhan, M. Ganesh

    2017-10-01

    A microstrip patch antenna is designed using a very thin layer of graphene as the radiating patch, which is fed by a microstrip transmission line. The graphene based patch is designed on a silicon substrate having a dielectric constant of 11.9, to radiate at a single frequency of 2.6 THz. Further, this antenna is made to resonate at dual frequencies of 2.48 THz and 3.35 THz, by changing the substrate height, which is reported for the first time. Various antenna parameters such as return loss, VSWR, gain, efficiency and bandwidth are also determined for the single and dual band operation. For the single band operation, a bandwidth of 145.4 GHz and an efficiency of 92% was achieved. For dual band operation, a maximum bandwidth of 140.5 GHz was obtained at 3.35 THz and an efficiency of 87.3% was obtained at the first resonant frequency of 2.48 THz. The absorption cross section of the antenna is also analysed for various substrate heights and has maximum peaks at the corresponding resonating frequencies. The simulation has been carried out by using a full wave electromagnetic simulator based on FDTD method.

  4. Circularly Polarized S Band Dual Frequency Square Patch Antenna Using Glass Microfiber Reinforced PTFE Composite

    Directory of Open Access Journals (Sweden)

    M. Samsuzzaman

    2014-01-01

    Full Text Available Circularly polarized (CP dual frequency cross-shaped slotted patch antenna on 1.575 mm thick glass microfiber reinforced polytetrafluoroethylene (PTFE composite material substrate is designed and fabricated for satellite applications. Asymmetric cross-shaped slots are embedded in the middle of the square patch for CP radiation and four hexagonal slots are etched on the four sides of the square patch for desired dual frequency. Different substrate materials have been analysed to achieve the desired operating band. The experimental results show that the impedance bandwidth is approximately 30 MHz (2.16 GHz to 2.19 GHz for lower band and 40 MHz (3.29 GHz to 3.33 GHz for higher band with an average peak gain of 6.59 dBiC and 5.52 dBiC, respectively. Several optimizations are performed to obtain the values of the antenna physical parameters. Moreover, the proposed antenna possesses compactness, light weight, simplicity, low cost, and circularly polarized. It is an attractive candidate for dual band satellite antennas where lower band can be used for uplink and upper band can be used for downlink.

  5. Nonuniform Overlapping Method in Designing Microstrip Patch Antennas Using Genetic Algorithm Optimization

    Directory of Open Access Journals (Sweden)

    J. M. Jeevani W. Jayasinghe

    2015-01-01

    Full Text Available Genetic algorithm (GA has been a popular optimization technique used for performance improvement of microstrip patch antennas (MPAs. When using GA, the patch geometry is optimized by dividing the patch area into small rectangular cells. This has an inherent problem of adjacent cells being connected to each other with infinitesimal connections, which may not be achievable in practice due to fabrication tolerances in chemical etching. As a solution, this paper presents a novel method of dividing the patch area into cells with nonuniform overlaps. The optimized design, which is obtained by using fixed overlap sizes, shows a quad-band performance covering GSM1800, GSM1900, LTE2300, and Bluetooth bands. In contrast, use of nonuniform overlap sizes leads to obtaining a pentaband design covering GSM1800, GSM1900, UMTS, LTE2300, and Bluetooth bandswith fractional bands with of 38% due to the extra design flexibility.

  6. One-turn stub-loaded loop patch antenna on a small ground plane

    DEFF Research Database (Denmark)

    Thaysen, Jesper; Jakobsen, Kaj Bjarne

    2005-01-01

    A small 1.1-cm3 one-turn loop patch antenna located 2.5 mm above an 18 × 25 mm ground plane separated by a dielectric substrate with relative permittivity of 9.8 is presented. By varying the length of a thin quarter-wavelength matching line, it is possible to change the resonant frequency. An RLC...... circuit model is used to determine the minimum quality factor Q. It is shown that the proposed loop yields a bandwidth performance close to the theoretical limit. The antenna has a 14.5% bandwidth at the resonant frequency of 2.04 GHz....

  7. Quality Factor Effect on the Wireless Range of Microstrip Patch Antenna Strain Sensors

    Directory of Open Access Journals (Sweden)

    Ali Daliri

    2014-01-01

    Full Text Available Recently introduced passive wireless strain sensors based on microstrip patch antennas have shown great potential for reliable health and usage monitoring in aerospace and civil industries. However, the wireless interrogation range of these sensors is limited to few centimeters, which restricts their practical application. This paper presents an investigation on the effect of circular microstrip patch antenna (CMPA design on the quality factor and the maximum practical wireless reading range of the sensor. The results reveal that by using appropriate substrate materials the interrogation distance of the CMPA sensor can be increased four-fold, from the previously reported 5 to 20 cm, thus improving considerably the viability of this type of wireless sensors for strain measurement and damage detection.

  8. Optimization of patch antennas via multithreaded simulated annealing based design exploration

    Directory of Open Access Journals (Sweden)

    James E. Richie

    2017-10-01

    Full Text Available In this paper, we present a new software framework for the optimization of the design of microstrip patch antennas. The proposed simulation and optimization framework implements a simulated annealing algorithm to perform design space exploration in order to identify the optimal patch antenna design. During each iteration of the optimization loop, we employ the popular MEEP simulation tool to evaluate explored design solutions. To speed up the design space exploration, the software framework is developed to run multiple MEEP simulations concurrently. This is achieved using multithreading to implement a manager-workers execution strategy. The number of worker threads is the same as the number of cores of the computer that is utilized. Thus, the computational runtime of the proposed software framework enables effective design space exploration. Simulations demonstrate the effectiveness of the proposed software framework.

  9. Study on an SRR-shaped left-handed material patch antenna

    Science.gov (United States)

    Song, X. H.; Chen, L. L.; Wu, C. H.; Yuan, Y. N.

    2011-03-01

    Left-handed material (LHM) is an artificial material. It has negative permittivity and negative permeability simultaneously and has attracted a great deal of attention in recent years. This paper investigates a patch antenna based on SRR-shaped left-handed material by using the method of finite difference time domain (FDTD). A patch antenna based on SRR and notches is designed by employing the traditional construction method; the results show that there exists a wave resonance state at 7.67 GHz, where its refraction index is close to - 1. The effect has greatly enhanced the electromagnetic wave's resonance intensity, and has improved the localized extent of the electromagnetic energy noticeably in such an LHM structure; besides, it can also enhance the radiation gain, broaden the frequency band, improve the impedance matching condition, and restrain the high harmonics.

  10. Genetic Algorithm Optimization of a High-Directivity Microstrip Patch Antenna Having a Rectangular Profile

    Directory of Open Access Journals (Sweden)

    J.W. Jayasinghe

    2013-09-01

    Full Text Available A single high-directivity microstrip patch antenna (MPA having a rectangular profile, which can substitute a linear array is proposed. It is designed by using genetic algorithms with the advantage of not requiring a feeding network. The patch fits inside an area of 2.54lambda x 0.25lambda, resulting in a broadside pattern with a directivity of 12 dBi and a fractional impedance bandwidth of 4%. The antenna is fabricated and the measurements are in good agreement with the simulated results. The genetic MPA provides a similar directivity as linear arrays using a corporate or series feeding, with the advantage that the genetic MPA results in more bandwidth.

  11. Dual-Band Pin-Patch Antenna for Wi-Fi Applications

    OpenAIRE

    Callaghan, Peter; Batchelor, John C.

    2008-01-01

    The pin-patch antenna provides a low-profile monopolar element suitable for wireless access point requirements. This design concept is extended here to provide dual-band operation. Experimental results are compared to predictions from a FDTD package confirming monopolar radiation in two bands at 2.4 GHz and 5.7 GHz. This band spacing can be adjusted from 1.8:1 to more than 4:1.

  12. Tracking antenna architectures based on an integrated mixer microstrip patch array

    CERN Document Server

    Gupta, S

    1997-01-01

    The object of this work is to design, develop and characterize both theoretically and experimentally a compact integrated mixer microstrip patch antenna which exhibits a low level of cross-polarization. Modelling of this antenna using various CAD techniques and supporting measurements has led to a clearer understanding of its operation and the optimization of its design. The attractiveness of such a frequency scaleable design lies in the inherent simplicity and ease with which it can be used to produce an intermediate frequency (IF) signal with minimum circuit complexity and low cross-polar levels. The operation of the integrated mixer antenna circuit is exploited under the phenomenon of injection locking for its potential for direct phase modulation and detection. It leads to new vistas of study such as IF phase-shifterless beam steering. Here the desired phased shift is derived through injection locking and achieved solely by the DC bias control, thus eliminating the need for phase shifters and feed network...

  13. Performance of a Wideband Cadmium Ferrite Microstrip Patch Antenna in the X-Band Region

    Science.gov (United States)

    Bhongale, S. R.; Ingavale, H. R.; Shinde, T. J.; Vasambekar, P. N.

    2017-10-01

    Magnesium-substituted cadmium ferrites with the chemical composition Mg x Cd1-x Fe2O4 (x = 0, 0.4 and 0.8) were prepared by an oxalate co-precipitation method under microwave sintering technique. The structural properties of ferrites were studied by x-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscope techniques. The scattering parameters such as reflection coefficient (S 11) and transmission coefficient (S 21) at microwave frequencies of palletized ferrites were measured by using a vector network analyzer. The software module 85071E followed by scattering parameters was used to determine the electromagnetic properties of the ferrites. The values determined for electromagnetic parameters such as the real part of permittivity (ɛ'), permeability (μ'), dielectric loss tangent (tanδ e) and magnetic loss tangent (tanδ m) of synthesized ferrites were used to design rectangular microstrip patch antennas. The performance of magnesium-substituted Cd ferrites as substrate for microstrip patch antennas was investigated. The antenna parameters such as return loss, bandwidth, voltage standing wave ratio, Smith chart and radiation pattern were studied. It is found that the Cd ferrite has applicability as a substrate for wideband antennas in the X-band region.

  14. Performance of a Wideband Cadmium Ferrite Microstrip Patch Antenna in the X-Band Region

    Science.gov (United States)

    Bhongale, S. R.; Ingavale, H. R.; Shinde, T. J.; Vasambekar, P. N.

    2018-01-01

    Magnesium-substituted cadmium ferrites with the chemical composition Mg x Cd1- x Fe2O4 ( x = 0, 0.4 and 0.8) were prepared by an oxalate co-precipitation method under microwave sintering technique. The structural properties of ferrites were studied by x-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscope techniques. The scattering parameters such as reflection coefficient ( S 11) and transmission coefficient ( S 21) at microwave frequencies of palletized ferrites were measured by using a vector network analyzer. The software module 85071E followed by scattering parameters was used to determine the electromagnetic properties of the ferrites. The values determined for electromagnetic parameters such as the real part of permittivity ( ɛ'), permeability ( μ'), dielectric loss tangent (tan δ e) and magnetic loss tangent (tan δ m) of synthesized ferrites were used to design rectangular microstrip patch antennas. The performance of magnesium-substituted Cd ferrites as substrate for microstrip patch antennas was investigated. The antenna parameters such as return loss, bandwidth, voltage standing wave ratio, Smith chart and radiation pattern were studied. It is found that the Cd ferrite has applicability as a substrate for wideband antennas in the X-band region.

  15. Circularly polarized triple band glass shaped monopole patch antenna with metallic reflector for bluetooth & wireless applications

    Energy Technology Data Exchange (ETDEWEB)

    Jangid, K. G.; Kulhar, V. S. [Department of Physics, Manipal University Jaipur, Jaipur-303007 (India); Choudhary, N.; Jain, P.; Sharma, B. R.; Saini, J. S.; Bhatnagar, D., E-mail: dbhatnagar-2000@rediffmail.com [Microwave Lab, Department of Physics, University of Rajasthan, Jaipur-302004 (India)

    2016-03-09

    This paper presents the design and performance of strip line fed glass shaped monopole patch antenna having with overall size 30mm × 30 mm × 1.59 mm. In the patch; an eight shaped slot and in the ground plane an eight shaped ring are introduced. A metallic ground plane is also introduced at appropriate location beneath the ground plane. The proposed antenna is simulated by applying CST Microwave Studio simulator. Antenna provides circularly polarized radiations, triple broad impedance bandwidth of 203MHz (2.306GHz to 2.510GHz), 42MHz (2.685GHz to 2.757GHz) & GHz (3.63 GHz to 6.05 GHz), high flat gain (close to 5dBi) and good radiation properties in the desired frequency range. This antenna may be a very useful tool for 2.45GHz Bluetooth communication band as well as for 2.4GHz/5.2 GHz /5.8 GHz WLAN bands & 3.7GHz/5.5 GHz Wi-Max bands.

  16. Circularly polarized triple band glass shaped monopole patch antenna with metallic reflector for bluetooth & wireless applications

    Science.gov (United States)

    Jangid, K. G.; Choudhary, N.; Jain, P.; Sharma, B. R.; Saini, J. S.; Kulhar, V. S.; Bhatnagar, D.

    2016-03-01

    This paper presents the design and performance of strip line fed glass shaped monopole patch antenna having with overall size 30mm × 30 mm × 1.59 mm. In the patch; an eight shaped slot and in the ground plane an eight shaped ring are introduced. A metallic ground plane is also introduced at appropriate location beneath the ground plane. The proposed antenna is simulated by applying CST Microwave Studio simulator. Antenna provides circularly polarized radiations, triple broad impedance bandwidth of 203MHz (2.306GHz to 2.510GHz), 42MHz (2.685GHz to 2.757GHz) & GHz (3.63 GHz to 6.05 GHz), high flat gain (close to 5dBi) and good radiation properties in the desired frequency range. This antenna may be a very useful tool for 2.45GHz Bluetooth communication band as well as for 2.4GHz/5.2 GHz /5.8 GHz WLAN bands & 3.7GHz/5.5 GHz Wi-Max bands.

  17. Design & Analysis of Microstrip Patch Antenna Using Different Dielectric Materials for WiMAX Communication System

    Directory of Open Access Journals (Sweden)

    Md. Moidul Islam

    2016-03-01

    Full Text Available This Paper presents Microstrip patch antenna for WiMAX communication system which operate at 5.8 GHz frequency band. The main objective of this paper is to design and observe the performance of the designed microstrip patch antenna for different dielectric materials. The size of the designed antenna has been also miniaturized. Better performance is observed for FR4 and dupont-951 dielectric material. For FR4 radiation efficiency is-2.776 dB and total efficiency is -3.026 dB at 5.8 GHz, this indicates better performance. And for dupont-951 the return loss is much lower comparing to the other dielectric materials used in this research, which is -16.609 dB. Also for dupont-951 and FR4, VSWR is found 1.35 and 1.7 respectively which is desirable. Also the size of the antenna has been reduced. In this paper we also observed and analyzed the radiation pattern of far field region, gain, radiation efficiency and total efficiency for different dielectric materials.

  18. A Broadband Single-Feed Circularly Polarized Patch Antenna with Wide Beamwidth

    Directory of Open Access Journals (Sweden)

    Changhong Zhang

    2015-01-01

    Full Text Available A broadband single-feed circularly polarized patch antenna with wide beamwidth is presented. The patch is coupled to four asymmetric cross slots via a microstrip ring with eight matching segments underneath the ground plane, traversing through the arms of the cross slots in a serial manner. And a coupling slice instead of a resistive load is used as matching load of the microstrip ring for higher gain. Furthermore, a metal side wall surrounding the antenna is used to improve the isolation between adjacent elements in an array. Through optimizing the four asymmetric cross slots and eight matching segments, excellent performances are achieved by the proposed antenna, especially for the broadband and wide beamwidth. Measurement results show that the antenna has −10 dB reflection coefficient bandwidth of 29.7%, 3-dB axial-ratio bandwidth of 21.6%, and beamwidth of more than 90°. It can be considered as a good candidate for the element of arrays.

  19. Tracking antenna architectures based on an integrated mixer microstrip patch array

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Sanjeev

    1997-07-01

    The object of this work is to design, develop and characterize both theoretically and experimentally a compact integrated mixer microstrip patch antenna which exhibits a low level of cross-polarization. Modelling of this antenna using various CAD techniques and supporting measurements has led to a clearer understanding of its operation and the optimization of its design. The attractiveness of such a frequency scaleable design lies in the inherent simplicity and ease with which it can be used to produce an intermediate frequency (IF) signal with minimum circuit complexity and low cross-polar levels. The operation of the integrated mixer antenna circuit is exploited under the phenomenon of injection locking for its potential for direct phase modulation and detection. It leads to new vistas of study such as IF phase-shifterless beam steering. Here the desired phased shift is derived through injection locking and achieved solely by the DC bias control, thus eliminating the need for phase shifters and feed networks. A self-tracking integrated mixer array has also been described which uses an in-band pilot carrier signal for self-calibration. By minor alteration of the integrated antenna topology, a minimum complexity variant of a heterodyne retrodirective array has then been realized. These tracking antenna architectures minimize the problems of cost, complexity and size limitations associated with conventional phased arrays. These are designed for emerging commercial applications and are resolutions of some trade-offs that balance performance, cost and reliability. Theoretical and experimental results are presented to show their performances and, in addition, the practical requirements relevant to these are also addressed. The results indicate that these tracking antenna architectures based on an integrated mixer microstrip patch array could form a synergistic link with other emerging technologies and can be to some extent embodied in future phased array designs

  20. On-chip patch antenna on InP substrate for short-range wireless communication at 140 GHz

    DEFF Research Database (Denmark)

    Dong, Yunfeng; Johansen, Tom Keinicke; Zhurbenko, Vitaliy

    2017-01-01

    This paper presents the design of an on-chip patch antenna on indium phosphide (InP) substrate for short-range wireless communication at 140 GHz. The antenna shows a simulated gain of 5.3 dBi with 23% bandwidth at 140 GHz and it can be used for either direct chip-to-chip communication or chip...

  1. Compact Double-P Slotted Inset-Fed Microstrip Patch Antenna on High Dielectric Substrate

    Directory of Open Access Journals (Sweden)

    M. R. Ahsan

    2014-01-01

    Full Text Available This paper presents a compact sized inset-fed rectangular microstrip patch antenna embedded with double-P slots. The proposed antenna has been designed and fabricated on ceramic-PTFE composite material substrate of high dielectric constant value. The measurement results from the fabricated prototype of the antenna show −10 dB reflection coefficient bandwidths of 200 MHz and 300 MHz with center resonant frequency of 1.5 GHz and 4 GHz, respectively. The fabricated antenna has attained gains of 3.52 dBi with 81% radiation efficiency and 5.72 dBi with 87% radiation efficiency for lower band and upper band, respectively. The measured E- and H-plane radiation patterns are also presented for better understanding. Good agreement between the simulation and measurement results and consistent radiation patterns make the proposed antenna suitable for GPS and C-band applications.

  2. Stepped Cylindrical Antenna with a Higher-Order Mode Ring Patch for Wideband Conical Radiation Pattern

    Directory of Open Access Journals (Sweden)

    Jinpil Tak

    2015-01-01

    Full Text Available A stepped cylindrical antenna with a higher-order mode ring patch for wideband conical radiation pattern is proposed. To accomplish a low profile with wideband conical radiation characteristics, a stepped cylindrical monopole and a TM41 higher-order mode ring patch with four shorting pins are utilized. The proposed antenna has a monopole-like radiation pattern with a wide 10-dB return loss bandwidth of 11 GHz (2 GHz–13 GHz. It can cover various wireless services, such as wireless broadband (WiBro; 2.3 GHz–2.39 GHz, wireless local area networks (WLAN; 2.4 GHz–2.484 GHz, 5.15 GHz–5.35 GHz, and 5.725 GHz–5.875 GHz, digital multimedia broadcasting (DMB; 2.63 GHz–2.655 GHz, and ultra wideband (UWB; 3.1 GHz–10.6 GHz. The antenna has a height of only 0.12λ0 at 2 GHz.

  3. Wearable Passive E-Textile UHF RFID Tag Based on a Slotted Patch Antenna with Sewn Ground and Microchip Interconnections

    Directory of Open Access Journals (Sweden)

    Johanna Virkki

    2017-01-01

    Full Text Available We present a wearable passive UHF RFID tag based on a slotted patch antenna comprising only textile materials (e-textile, textile substrate, and conductive yearn. As a novel manufacturing approach, we realize the patch-to-ground and antenna-to-IC interfaces using only conductive thread and a sewing machine. We outline the electromagnetic optimization of the antenna for body-worn operation through simulations and present a performance comparison between the e-textile tag and a tag produced using regular electronics materials and methods. The measured results show that the textile tag achieves the electrical performance required in practical applications and that the slotted patch type antenna provides stable electromagnetic performance in different body-worn configurations.

  4. Design of UWB Planar Monopole Antennas with Etched Spiral Slot on the Patch for Multiple Band-Notched Characteristics

    Directory of Open Access Journals (Sweden)

    Swarup Das

    2015-01-01

    Full Text Available Three types of Ultrawideband (UWB antennas with single, double, and triple notched bands are proposed and investigated for UWB communication applications. The proposed antennas consist of CPW fed monopole with spiral slot etched on the patch. In this paper single, double, and also triple band notches with central frequency of 3.57, 5.12, and 8.21 GHz have been generated by varying the length of a single spiral slot. The proposed antenna is low-profile and of compact size. A stable gain is obtained throughout the operation band except the three notched frequencies. The antennas have omnidirectional and stable radiation patterns across all the relevant bands. Moreover, relatively consistent group delays across the UWB frequencies are noticed for the triple notched band antenna. A prototype of the UWB antenna with triple notched bands is fabricated and the measured results of the antenna are compared with the simulated results.

  5. Back Radiation Suppression through a Semitransparent Ground Plane for a mm-Wave Patch Antenna

    KAUST Repository

    Klionovski, Kirill

    2017-06-21

    Omnidirectional radiation pattern with minimum backward radiation is highly desirable for base station antennas to minimize the multipath effects. Semitransparent ground planes have been used to reduce the backward radiation, but mostly with complicated non-uniform impedance distribution. In this work, we propose, for the first time, a round semitransparent ground plane of radius 0.8 λ with uniform impedance distribution that can improve the front-to-back ratio of a wideband patch antenna by 11.6 dB as compared to a similar sized metallic ground plane. The value of uniform impedance is obtained through analytical optimization by using asymptotic expressions in the Kirchhoff approximation of the radiation pattern of a toroidal wave scattered by a round semitransparent ground plane. The semitransparent ground plane has been realized using a low-cost carbon paste on a Kapton film. Experimental results match closely with those of simulations and validate the overall concept.

  6. Optimizations of Patch Antenna Arrays Using Genetic Algorithms Supported by the Multilevel Fast Multipole Algorithm

    Directory of Open Access Journals (Sweden)

    C. Onol

    2014-12-01

    Full Text Available We present optimizations of patch antenna arrays using genetic algorithms and highly accurate full-wave solutions of the corresponding radiation problems with the multilevel fast multipole algorithm (MLFMA. Arrays of finite extent are analyzed by using MLFMA, which accounts for all mutual couplings between array elements efficiently and accurately. Using the superposition principle, the number of solutions required for the optimization of an array is reduced to the number of array elements, without resorting to any periodicity and similarity assumptions. Based on numerical experiments, genetic optimizations are improved by considering alternative mutation, crossover, and elitism mechanisms. We show that the developed optimization environment based on genetic algorithms and MLFMA provides efficient and effective optimizations of antenna excitations, which cannot be obtained with array-factor approaches, even for relatively simple arrays with identical elements.

  7. Illustration of the Impedance Behaviour of Extremely Low-Profile Coupled Shorted-Patches Antennas for UHF RFID of People

    Directory of Open Access Journals (Sweden)

    Milan Svanda

    2014-01-01

    Full Text Available The recently introduced coupled shorted-patches technique for the design of extremely low-profile UHF RFID tag antennas is used to illustrate the flexibility of selected feeding methods for tuning the antenna input impedance for the complex values required for matching with typical RFID chips. We present parametric studies of the impedance behaviour of dipole-excited and directly excited antennas designed for radiofrequency identification of people in the European UHF frequency band. Our study can significantly facilitate the design of this class of on-body tag antennas.

  8. Miniaturized Dual Band Multislotted Patch Antenna on Polytetrafluoroethylene Glass Microfiber Reinforced for C/X Band Applications

    Directory of Open Access Journals (Sweden)

    M. T. Islam

    2014-01-01

    Full Text Available This paper introduces a new configuration of compact, triangular- and diamond-slotted, microstrip-fed, low-profile antenna for C/X band applications on polytetrafluoroethylene glass microfiber reinforced material substrate. The antenna is composed of a rectangular-shaped patch containing eight triangles and two diamond-shaped slots and an elliptical-slotted ground plane. The rectangular-shaped patch is obtained by cutting two diamond slots in the middle of the rectangular patch, six triangular slots on the left and right side of the patch, and two triangular slots on the up and down side of the patch. The slotted radiating patch, the elliptical-slotted ground plane, and the microstrip feed enable the matching bandwidth to be widened. A prototype of the optimized antenna was fabricated on polytetrafluoroethylene glass microfiber reinforced material substrate using LPKF prototyping machine and investigated to validate the proposed design. The simulated results are compared with the measured data, and good agreement is achieved. The proposed antenna offers fractional bandwidths of 13.69% (7.78–8.91 GHz and 10.35% (9.16–10.19 GHz where S11 < −10 dB at center frequencies of 8.25 GHz and 9.95 GHz, respectively, and relatively stable gain, good radiation efficiency, and omnidirectional radiation patterns in the matching band.

  9. Ultra-Wide Patch Antenna Array Design at 60 GHz Band for Remote Vital Sign Monitoring with Doppler Radar Principle

    Science.gov (United States)

    Rabbani, Muhammad Saqib; Ghafouri-Shiraz, Hooshang

    2017-05-01

    In this paper, ultra-wide patch antenna arrays have been presented at 60 GHz band (57.24-65.88 GHz) with improved gain and beam-width capabilities for remote detection of respiration and heart beat rate of a person with Doppler radar principle. The antennas measured and simulation results showed close agreement. The breathing rate (BR) and heart rate (HR) of a 31-year-old man have been accurately detected from various distances ranging from 5 to 200 cm with both single-antenna and dual-antenna operations. In the case of single-antenna operation, the signal is transmitted and received with the same antenna, whereas in dual-antenna operation, two identical antennas are employed, one for signal transmission and the other for reception. It has been found that in case of the single-antenna operation, the accuracy of the remote vital sign monitoring (RVSM) is good for short distance; however, in the case of the dual-antenna operations, the RVSM can be accurately carried out at relatively much longer distance. On the other hand, it has also been seen that the visual results are more obvious with higher gain antennas when the radar beam is confined just on the subject's body area.

  10. Compact Circularly Polarized Patch Antenna Using a Composite Right/Left-Handed Transmission Line Unit-Cell

    Directory of Open Access Journals (Sweden)

    L. Geng

    2013-04-01

    Full Text Available A compact circularly polarized (CP patch antenna using a composite right/left-handed (CRLH transmission line (TL unit-cell is proposed. The CRLH TL unit-cell includes a complementary split ring resonator (CSRR for shunt inductance and a gap loaded with a circular-shaped slot for series capacitance. The CSRR can decrease the TM10 mode resonance frequency, thus reducing the electrical size of the proposed antenna. In addition, the asymmetry of the CSRR brings about the TM01 mode, which can be combined with the TM10 mode by changing the slot radius. The combination of these two orthogonal modes with 90° phase shift makes the proposed antenna provide a CP property. The experimental results show that the proposed antenna has a wider axial ratio bandwidth and a smaller electrical size than the reported CP antennas. Moreover, the proposed antenna is designed without impedance transformer, 90° phase shift, dual feed and ground via.

  11. Design and Comparison of 24 GHz Patch Antennas on Glass Substrates for Compact Wireless Sensor Nodes

    Directory of Open Access Journals (Sweden)

    Florian Ohnimus

    2010-01-01

    Full Text Available Three patch antennas suitable for integration and operation in a compact 24 GHz wireless sensor node with radar and communication functions are designed, characterized, and compared. The antennas are manufactured on a low loss glass wafer using thin film (BCB/Cu wafer level processing (WLP technologies. This process is well suited for 3D stacking. The antennas are fed through a microstrip line underneath a ground plane coupling into the patch resonator through a slot aperture. Linear polarization (LP, dual mode (DM operation, and circular polarization (CP are achieved through the layout of the slot aperture and rectangular patch dimensions. Antenna gain values of ∼5.5 dBi are obtained in addition to the 10 dB impedance bandwidths of 900 MHz and 1.3 GHz as well as 500 MHz CP bandwidth with a 3 dB axial ratio for the LP, DM, and CP patch antennas, respectively.

  12. Engineering the Losses and Beam Divergence in Arrays of Patch Antenna Microcavities for Terahertz Sources

    Science.gov (United States)

    Madéo, Julien; Pérez-Urquizo, Joel; Todorov, Yanko; Sirtori, Carlo; Dani, Keshav M.

    2017-11-01

    We perform a comprehensive study on the emission from finite arrays of patch antenna microcavities designed for the terahertz range by using a finite element method. The emission properties including quality factors, far-field pattern, and photon extraction efficiency are investigated for etched and non-etched structures as a function of the number of resonators, the dielectric layer thickness, and period of the array. In addition, the simulations are achieved for lossy and perfect metals and dielectric layers, allowing to extract the radiative and non-radiative contributions to the total quality factors of the arrays. Our study shows that this structure can be optimized to obtain low beam divergence (FWHM 50% while keeping a strongly localized mode. These results show that the use of these microcavities would lead to efficient terahertz emitters with a low divergence vertical emission and engineered losses.

  13. Stroke Diagnosis using Microstrip Patch Antennas Based on Microwave Tomography Systems

    Directory of Open Access Journals (Sweden)

    Sakthisudhan K

    2017-03-01

    Full Text Available Microwave tomography (MT based on stroke diagnosis is one of the alternative methods for determinations of the haemorrhagic, ischemic and stroke in brain nervous systems. It is focusing on the brain imaging, continuous monitoring, and preclinical applications. It provides cost effective system and able to use the rural and urban medical clinics that lack the necessary resources in effective stroke diagnosis during emerging applications in road accident and pre-ambulance clinical treatment. In the early works, the design of microstrip patch antennas (MPAs involved the implementation of MT system. Consequently, the MT system presented a few limitations since it required an efficient MPA design with appropriate parameters. Moreover, there were no specific diagnosis modules and body centric features in it. The present research proposes the MPA designs in the forms of diagnosis modules and implements it on the MT system.

  14. Extremely Low-Profile Circular Patch-Ring Antenna with A Shorting Via for Impedance Matching Improvement

    DEFF Research Database (Denmark)

    Zhang, Shuai; Syrytsin, Igor A.; Sørensen, Morten

    2017-01-01

    An extremely low-profile circular patch-ring antenna with omnidirectional radiation patterns is proposed in this paper. By simply introducing a shorting via, the impedance matching of the antenna is improved, where both TM31 mode and TM32 mode are excited efficiently to realize a dual resonance...... behavior. The designed antenna covers the Wi-Fi band of 2.4- 2.48 GHz with the realized gain of over 1.5 dBi and the thickness of 0.005 λ (λ is the wavelength of the lowest operating frequency in free space). Since the antenna is not sensitive to size of ground plane, it is suitable to be mounted...

  15. An isolation-enhanced quad-element antenna using suspended solid wires for LTE small-cell base stations

    Science.gov (United States)

    Chen, Yen-Sheng; Zhou, Huang-Cheng

    2017-05-01

    This paper presents a multiple-input-multiple-output (MIMO) antenna that has four-unit elements enabled by an isolation technique for long-term evolution (LTE) small-cell base stations. While earlier studies on MIMO base-station antennas cope with either a lower LTE band (698-960 MHz) or an upper LTE band (1710-2690 MHz), the proposed antenna meets the full LTE specification, yet it uses the maximum number of unit elements to increase channel capacity. The antenna configuration is optimized for good impedance matching and high radiation efficiency. In particular, as the spacing between unit elements is so small that severe mutual coupling occurs, we propose a simple structure with extremely low costs to enhance the isolation. By using suspended solid wires interconnecting the position having strong coupled current of two adjacent elements, an isolation enhancement of 37 dB is achieved. Although solid wires inherently aim at direct-current applications, this work successfully employs such a low-cost technique to microwave antenna development. Experimental results have validated the design guidelines and the proposed configuration, showing that antenna performances including impedance matching, isolation, radiation features, signal correlation, and channel capacity gain are highly desired for LTE small-cell base stations.

  16. Synthesis of bismuth titanate (BTO) nanopowder and fabrication of microstrip rectangular patch antenna

    Science.gov (United States)

    Thiruramanathan, P.; Sharma, Sanjeev K.; Sankar, S.; Sankar Ganesh, R.; Marikani, A.; Kim, Deuk Young

    2016-12-01

    The bismuth titanate (Bi4Ti3O12) or BTO nanopowder was synthesized from the combustion method and fabricated a microstrip rectangular patch antenna (MPA). The crystal structure and lattice spacing of BTO were evaluated from XRD, TEM, and SAED analysis. The crystal structure of BTO (annealed at 900 °C) was observed to be the orthorhombic phase with fcc lattice. The microstructure of BTO nanoparticles was confirmed the spherical and hexagonal shapes, which were slightly agglomerated due to the lack of stabilizing surfactants. The presence of weak and wide bands in Raman spectrum quantified the mechanical compressions to the uniform directions of elongated lattice constants and tensions to the lattice constriction of crystalline bismuth titanate. To fabricate the MPA, pellets of BTO nanopowder were prepared by applying the uniaxial pressure in the dimension of 1.5 mm thickness and 8 mm diameter. These pellets were formed a densely packed structure close to the theoretical density. The coercivity and remanence polarization of BTO ceramics increased as the applied field increased. The inexpensive combustion synthesis method of BTO nanopowder showed the high dielectric constant (ɛ' = 450) and low dielectric loss (tan δ = 0.98), which has a potential implication of the cost-effectiveness in the field of miniaturized microelectronics. The synthesis and measurements of BTO ceramics are found to be suitable for wireless communication systems.

  17. Wideband low-profile low-temperature co-fired ceramic patch antenna with a differential-fed structure

    Directory of Open Access Journals (Sweden)

    Wen-Jian Sun

    2017-04-01

    Full Text Available A novel wideband patch antenna with a differential-fed structure is proposed in this study. For this antenna, an H-shaped patch is first adopted to build a compact design. Then, by introducing a via-wall-plate pair as the differential feeding scheme, favourable radiation patterns and enhanced operating bandwidth can be achieved in a low profile. Furthermore, a Marchand balun is incorporated into the overall design to facilitate the test and direct integration with existing single-end radio-frequency circuits. The proposed antenna, which is designed and fabricated, using low-temperature co-fired ceramic technology, could be used to develop a highly integrated system-in-package. The measured results demonstrate that the proposed antenna with a low profile of 0.06λ(0 obtains an impedance bandwidth of 11.2%, a peak gain of 7.1 dBi, and a low cross-polarisation of better than −20 dB.

  18. Novel Microstrip Patch Antennas with Frequency Agility, Polarization Reconfigurability, Dual Null Steering Capability and Phased Array Antenna with Beam Steering Performance

    Science.gov (United States)

    Babakhani, Behrouz

    Nowadays the wireless communication technology is playing an important role in our daily life. People use wireless devices not only as a conventional communication device but also as tracking and navigation tool, web browsing tool, data storage and transfer tool and so for many other reasons. Based on the user demand, wireless communication engineers try to accommodate as many as possible wireless systems and applications in a single device and therefore, creates a multifunctional device. Antenna, as an integral part of any wireless communication systems, should also be evolved and adjusted with development of wireless transceiver systems. Therefore multifunctional antennas have been introduced to support and enhance the functionality on modern wireless systems. The main focus and contribution of this thesis is design of novel multifunctional microstrip antennas with frequency agility, polarization reconfigurablity, dual null steering capability and phased array antenna with beam steering performance. In this thesis, first, a wide bandwidth(1.10 GHz to 1.60 GHz) right-handed circularly polarized (RHCP) directional antenna for global positioning system (GPS) satellite receive application has been introduced which covers all the GPS bands starting from L1 to L5. This design consists of two crossed bow-tie dipole antennas fed with sequentially phase rotated feed network backed with an artificial high impedance surface (HIS) structure to generate high gain directional radiation patterns. This design shows good CP gain and axial ratio (AR) and wide beamwidth performance. Although this design has good radiation quality, the size and the weight can be reduced as future study. In the second design, a frequency agile antenna was developed which also covers the L-band (L1 to L5) satellite communication frequencies. This frequency agile antenna was designed and realized by new implementation of varactor diodes in the geometry of a circular patch antenna. Beside wide frequency

  19. Miniature size multiband planar patch antenna fabricated on a bioplastic substrate

    National Research Council Canada - National Science Library

    M.R. Ahsan; M.T. Islam; M. Habib Ullah; H. Arshad; M.T. Ali

    2015-01-01

    .... The prototype of the antenna has been fabricated 1.0 mm thick ceramic filled bioplastic substrate by using optimal dimension obtained from design/simulations and antenna performances are experimentally tested...

  20. Bandwidth enhancement of electromagnetic coupled nonuniform H-shaped microstrip patch antenna for higher band of Wi-MAX applications

    Energy Technology Data Exchange (ETDEWEB)

    Bhardwaj, Dheeraj, E-mail: dbhardwaj.bit@gmail.com [Assistant Professor, Department of Physics, BIT-Mesra-Jaipur Campus, Jaipur 302017 (India); Gulati, Gitansh, E-mail: gitanshgulati@gmail.com [Bachelor of Engineering-ECE, BIT-Mesra-Jaipur Campus, Jaipur 302017 (India); Saraswat, Srishti, E-mail: saraswat.srishti@yahoo.in [Bachelor of Engineering-VII Sem, ECE, BIT-Mesra-Jaipur Campus, Jaipur 302017 (India); Sharma, Komal, E-mail: kbhardwaj18@gmail.com [Reader, Department of Physics, Swami Keshvanand Institute of Technology, Jaipur 302017 (India)

    2016-03-09

    The bandwidth enhancement of a stacked non-uniform electromagnetically coupled H-shaped Microstrip Antenna (SNHMA) with tapered edges is analyzed and simulated using the IE3D simulator. The proposed antenna prototype is drafted on FR-4 material and stacked further with an air discontinuity of 0.3 mm to the next layer. The various parameters optimized to achieve the best performance from the modified SNHMA primarily include a)length b)width of the patch c)air gap thickness. The redesigned antenna serves at two distinct frequencies with an elevated bandwidth of 30.85 % at the central frequency 5.762 GHz, approximately four times the bandwidth of the standard patch having the same dimensions. The simulated radiation patterns (E-plane and H-plane) are exhibited within the range of frequencies where the broadband response is observed. The specifications of the proposed structure make it promising for the higher band of Wi-MAX applications.

  1. Reconfigurable Wideband Circularly Polarized Stacked Square Patch Antenna for Cognitive Radios

    Science.gov (United States)

    Barbosa Kortright, Miguel A.; Waldstein, Seth W.; Simons, Rainee N.

    2017-01-01

    An almost square patch, a square patch and a stacked square patch with corner truncation for circular polarization (CP) are researched and developed at X-band for cognitive radios. Experimental results indicate, first, that the impedance bandwidth of a CP almost square patch fed from the edge by a 50 ohm line is 1.70 percent and second, that of a CP square patch fed from the ground plane side by a surface launch connector is 1.87 percent. Third, the impedance bandwidth of a CP stacked square patch fed by a surface launch connector is 2.22 percent. The measured center frequency for the CP square patch fed by a surface launch connector without and with an identical stacked patch is 8.45 and 8.1017 GHz, respectively. By stacking a patch, separated by a fixed air gap of 0.254 mm, the center frequency is observed to shift by as much as 348.3 MHz. The shift in the center frequency can be exploited to reconfigure the operating frequency by mechanically increasing the air gap. The results indicate that a tuning bandwidth of about 100 MHz can be achieved when the distance of separation between the driven patch and the stacked patch is increased from its initial setting of 0.254 to 1.016 mm.

  2. Use of microstrip patch antennas in grain and pulverized materials permittivity measurement

    Science.gov (United States)

    El Sabbagh, M.A.; Ramahi, O.M.; Trabelsi, S.; Nelson, S.O.; Khan, L.

    2003-01-01

    A free-space microwave system developed for the measurement of the relative complex permittivity of granular materials and of pulverized materials was reported. The system consists of a transmitting antenna and a receiving antenna separated by a space filled by the sample to be characterized and a network analyzer for transmission measurement. The receiving antenna was mounted on a movable plate, which gives the flexibility of having different sample thicknesses.

  3. High-Performance Wireless Ammonia Gas Sensors Based on Reduced Graphene Oxide and Nano-Silver Ink Hybrid Material Loaded on a Patch Antenna.

    Science.gov (United States)

    Wu, Bian; Zhang, Xingfei; Huang, Beiju; Zhao, Yutong; Cheng, Chuantong; Chen, Hongda

    2017-09-09

    Reduced graphene oxide (rGO) has been studied as a resistive ammonia gas sensor at room temperature. The sensitive hybrid material composed of rGO and nano-silver ink (Ag-ink) was loaded on a microstrip patch antenna to realize high-performance wireless ammonia sensors. The material was investigated using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Firstly, interdigital electrodes (IDEs) printed on the polyethylene terephthalate (PET) by direct printing were employed to measure the variation of resistance of the sensitive material with the ammonia concentration. The results indicated the response of sensor varied from 4.25% to 14.7% under 15-200 ppm ammonia concentrations. Furthermore, the hybrid material was loaded on a microstrip patch antenna fabricated by a conventional printed circuit board (PCB) process, and a 10 MHz frequency shift of the sensor antenna could be observed for 200 ppm ammonia gas. Finally, the wireless sensing property of the sensor antenna was successfully tested using the same emitted antenna outside the gas chamber with a high gain of 5.48 dBi, and an increased reflection magnitude of the emitted antenna due to the frequency mismatch of the sensor antenna was observed. Therefore, wireless ammonia gas sensors loaded on a patch antenna have significant application prospects in the field of Internet of Things (IoTs).

  4. Joint Optimization of Microstrip Patch Antennas Using Particle Swarm Optimization for UWB Systems

    Directory of Open Access Journals (Sweden)

    Muhammad Zubair

    2013-01-01

    Full Text Available Ultra wideband (UWB systems are the most appropriate for high data rate wireless transmission with low power consumption. However, the antenna design for UWB has been a challenging task. Moreover, it is always desirable to have more freedom by designing different shape antennas with identical characteristics so that they can be used in either transmitter or receiver depending on other physical constraints such as area. To tackle these issues, in this paper, we have investigated a joint optimization of three different shape-printed monopole antennas, namely, printed square monopole antenna, printed circular monopole antenna and printed hexagonal monopole antenna, for UWB applications. More specifically, we have obtained the optimized geometrical parameters of these antennas by minimizing the mean-square-error for desired lower band edge frequency, quality factor, and bandwidth. The objective of joint optimization is to have identical frequency characteristics for the aforementioned three types of PMA which will give a freedom to interchangeably use them at either side, transmitting or receiving. Moreover, we employ particle swarm optimization (PSO algorithm for our problem as it is well known in the literature that PSO performs well in electromagnetic and antenna applications. Simulation results are presented to show the performance of the proposed design.

  5. Dual Polarization Stacked Microstrip Patch Antenna Array With Very Low Cross-Polarization

    DEFF Research Database (Denmark)

    Granholm, Johan; Woelders, Kim

    2001-01-01

    This paper describes the development and performance of a wideband dual linear polarization microstrip antenna array used in the Danish high-resolution airborne multifrequency polarimetric synthetic aperture radar, EMISAR. The antenna was designed for an operating frequency of 1.25 GHz±50 MHz...

  6. Modified Sierpinski Gasket Patch Antenna for UMTS and 2.4/5.2 WLAN

    Directory of Open Access Journals (Sweden)

    Y. E. Ali

    2013-05-01

    Full Text Available A modified Sierpinski Gasket fractal antenna for multiband application is proposed in this paper. The modified ground plane and the microstrip feed are used to obtain the wider bandwidth at the resonance frequency. The antenna is designed and printed on two layers FR-4 substrate (ϵr=4.4 and h=1.6 mm to cover the UMTS and 2.4/5.2 WLAN. The radiation pattern of the proposed antenna is similar to an omnidirectional. The proposed antenna has maximum gain of 1.88, 1.6, 4.31 dB at 2, 2.4, 5.2 GHz, respectively The properties of the antenna such as return losses, radiation pattern, input resistance and gain are determined via numerical CST Microwave Studio 2010 software.

  7. Design of Ultra-Thin and Compact Metamaterial Monopolar Patch Antenna with Broad Bandwidth

    Science.gov (United States)

    Lin, Bi-Cheng; Wang, Guang-Ming

    2017-12-01

    A novel magneto-electro-dielectric waveguided metamaterial (MED-WG-MTM) that the effective permeability ɛeff is changed obviously with the decrease of substrate's thickness is proposed. The proposed MTM can be used to simultaneously achieve the miniaturization and ultra-thin profile of overall antenna. Then, for demonstrated the characteristic, a coplanar-waveguide (CPW)-fed antenna by loading the proposed MTM is designed, fabricated, and measured. The measured result shows that the S11 less than -10 dB is from 1.48 to 5.08 GHz (109.7 % bandwidth) and 72 % miniaturization is achieved. The results between simulation and measurement coincide well. The thickness of the overall antenna is only 0.003λmax, which is smallest compared with the reported ones. (λmax is the wavelength at the lowest operating frequency).

  8. Dual Band Parasitic Element Patch Antenna for LTE/WLAN Applications

    Directory of Open Access Journals (Sweden)

    BAG Biplab

    2017-05-01

    Full Text Available In this paper, a single layer coaxial fed dual band slotted microstrip antenna is proposed. The proposed antenna consists of two direct couple parasitic elements and L-shape slots on the main resonating element. Two resonant modes are excited and it covers 4G LTE and WLAN middle band. The -10dB impedance bandwidth for resonant frequency of 2.35GHz and 5.28GHz are 140MHz (2.25-2.39GHz and 570MHz (5.18-5.75GHz, respectively. The measured VSWR at 2.35GHz is 1.27 and at 5.28GHz is 1.41. The proposed antenna is simple in design and compact in size. The simulated and measured results are in good agreement.

  9. Dual Band Parasitic Element Patch Antenna for LTE/WLAN Applications

    OpenAIRE

    BAG Biplab; SARKAR Partha Pratim

    2017-01-01

    In this paper, a single layer coaxial fed dual band slotted microstrip antenna is proposed. The proposed antenna consists of two direct couple parasitic elements and L-shape slots on the main resonating element. Two resonant modes are excited and it covers 4G LTE and WLAN middle band. The -10dB impedance bandwidth for resonant frequency of 2.35GHz and 5.28GHz are 140MHz (2.25-2.39GHz) and 570MHz (5.18-5.75GHz), respectively. The measured VSWR at 2.35GHz is 1.27 and at 5.28GHz is 1.41. The pro...

  10. All-Metal Dual-Polarized W-band Patch Element for Phased Array Antenna Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Metal patches were developed for the Juno Microwave radiometer instrument at P-band and L-band. The absence of dielectric in the metal patch design obviated issues...

  11. Study of LDPE/TiO2 and PS/TiO2 Composites as Potential Substrates for Microstrip Patch Antennas

    Science.gov (United States)

    Sarmah, Debashis; Deka, Juti R.; Bhattacharyya, Satyajib; Bhattacharyya, Nidhi S.

    2010-10-01

    Low-density polyethylene (LDPE)/titania (TiO2) and polystyrene (PS)/titania (TiO2) composite systems have been developed as alternative substrates for microstrip patch antennas (MPA) for handheld devices. Morphological, thermal, and microwave characterizations of these composites have been conducted for different volume fractions of TiO2 in the polymer matrix. The size of the titania particles was found to be of the order of 0.5 μm, and their distribution in the composite was quite uniform. Composite materials showed an improvement in thermal and microwave properties over the parent polymer. Verification of these composites as potential substrates for MPA was carried out by fabricating simple rectangular patch X-band antennas. Materials with optimized substrate properties were chosen to design the MPA. The patches were designed with 4% volume fraction TiO2 in the LDPE composite system and 6% volume fraction TiO2 in the PS composite system. Return loss of ˜18 dB was observed for both systems.

  12. Circularly polarized antennas

    CERN Document Server

    Gao, Steven; Zhu, Fuguo

    2013-01-01

    This book presents a comprehensive insight into the design techniques for different types of CP antenna elements and arrays In this book, the authors address a broad range of topics on circularly polarized (CP) antennas. Firstly, it introduces to the reader basic principles, design techniques and characteristics of various types of CP antennas, such as CP patch antennas, CP helix antennas, quadrifilar helix antennas (QHA), printed quadrifilar helix antennas (PQHA), spiral antenna, CP slot antennas, CP dielectric resonator antennas, loop antennas, crossed dipoles, monopoles and CP horns. Adva

  13. Microelectromechanical Systems Actuator Based Reconfigurable Printed Antenna

    Science.gov (United States)

    Simons, Rainee N. (Inventor)

    2005-01-01

    A polarization reconfigurable patch antenna is disclosed. The antenna includes a feed element, a patch antenna element electrically connected to the feed element, and at least one microelectromechanical systems (MEMS) actuator, with a partial connection to the patch antenna element along an edge of the patch antenna element. The polarization of the antenna can be switched between circular polarization and linear polarization through action of the at least one MEMS actuator.

  14. Patch Antenna for Measuring the Internal Temperature of Biological Objects Using the Near-Field Microwave Radiometric Method

    Science.gov (United States)

    Ubaichin, A.; Bespalko, A.; Filatov, A.; Alexeev, E.; Zhuk, G.

    2016-01-01

    The near-field microwave antenna with central frequency of 2.23 GHz has been designed and manufactured to be used as a part of the medical microwave radiometric system. Experimental studies of the reflection coefficient in different parts of the human body were conducted using the developed antenna. The experimental studies were carried out in a group of volunteers with normal somatic growth. The results of the experiments were used to perform the analysis of the potential errors in the measurements obtained via the developed antenna.

  15. Extremely Low-Profile Circular Patch-Ring Antenna with A Shorting Via for Impedance Matching Improvement

    DEFF Research Database (Denmark)

    Zhang, Shuai; Syrytsin, Igor A.; Sørensen, Morten

    2017-01-01

    behavior. The designed antenna covers the Wi-Fi band of 2.4- 2.48 GHz with the realized gain of over 1.5 dBi and the thickness of 0.005 λ (λ is the wavelength of the lowest operating frequency in free space). Since the antenna is not sensitive to size of ground plane, it is suitable to be mounted...

  16. A Design Of Feeding Network For A Dual-Linear Polarization, Stacked, Probe-Fed Microstrip Patch Antenna Array

    DEFF Research Database (Denmark)

    Jaworski, G.; Krozer, Viktor

    2004-01-01

    Components of multilayer feed network are presented for application in broad-band dual-linear polarized stacked C-band antenna. Measurement results of wide band matching circuits and different types of power divider networks constituting parts of BFN demonstrate wideband operation. Suitable...

  17. Thematic mapper research in the earth sciences: Small scale patches of suspended matter and phytoplankton in the Elbe River Estuary, German Bight and Tidal Flats

    Science.gov (United States)

    Grassl, H.; Doerffer, R.; Fischer, J.; Brockmann, C.; Stoessel, M.

    1987-01-01

    A Thematic Mapper (TM) field experiment was followed by a data analysis to determine TM capabilities for analysis of suspended matter and phytoplankton. Factor analysis showed that suspended matter concentration, atmospheric scattering, and sea surface temperature can be retrieved as independent factors which determine the variation in the TM data over water areas. Spectral channels in the near infrared open the possibility of determining the Angstrom exponent better than for the coastal zone color scanner. The suspended matter distribution may then be calculated by the absolute radiance of channel 2 or 3 or the ratio of both. There is no indication of whether separation of chlorophyll is possible. The distribution of suspended matter and sea surface temperature can be observed with the expected fine structure. A good correlation between water depth and suspended matter distribution as found from ship data can now be analyzed for an entire area by the synoptic view of the TM scenes.

  18. Multi-walled carbon nanotube-based RF antennas

    Science.gov (United States)

    Elwi, Taha A.; Al-Rizzo, Hussain M.; Rucker, Daniel G.; Dervishi, Enkeleda; Li, Zhongrui; Biris, Alexandru S.

    2010-01-01

    A novel application that utilizes conductive patches composed of purified multi-walled carbon nanotubes (MWCNTs) embedded in a sodium cholate composite thin film to create microstrip antennas operating in the microwave frequency regime is proposed. The MWCNTs are suspended in an adhesive solvent to form a conductive ink that is printed on flexible polymer substrates. The DC conductivity of the printed patches was measured by the four probe technique and the complex relative permittivity was measured by an Agilent E5071B probe. The commercial software package, CST Microwave Studio (MWS), was used to simulate the proposed antennas based on the measured constitutive parameters. An excellent agreement of less than 0.2% difference in resonant frequency is shown. Simulated and measured results were also compared against identical microstrip antennas that utilize copper conducting patches. The proposed MWCNT-based antennas demonstrate a 5.6% to 2.2% increase in bandwidth, with respect to their corresponding copper-based prototypes, without significant degradation in gain and/or far-field radiation patterns.

  19. A Novel Multiband Miniature Planar Inverted F Antenna Design for Bluetooth and WLAN Applications

    Directory of Open Access Journals (Sweden)

    J. M. Jeevani W. Jayasinghe

    2015-01-01

    Full Text Available A novel compact planar inverted F antenna (PIFA optimized using genetic algorithms for 2.4 GHz (Bluetooth and 5 GHz (UNII-1, UNII-2, UNII-2 extended, and UNII-3 bands is presented. The patch with a shorting pin is on a 20×7×0.762 mm3 substrate, which is suspended in air 5 mm above a 30×7 mm2 ground plane. Genetic algorithm optimization (GAO is used to optimize the patch geometry, feed position, and shorting pin position simultaneously. Simulations are carried out by using HFSS and a prototype antenna is fabricated to compare the measurements with the simulations. The antenna shows fractional impedance bandwidths of 4% and 21% and gains of 2.5 dB and 3.2 dB at lower and upper bands, respectively.

  20. MULTIBAND MILLIMETER WAVE T-SHAPED ANTENNA WITH ...

    African Journals Online (AJOL)

    The proposed antenna consists of T-shape radiating patch mounted on rectangular substrate (FR4-4) and microstrip line for antenna feeding. An evolutionary algorithm called particle swarm optimization was used to optimize the length and width of the proposed antenna patch. The proposed antenna gives triple bands with ...

  1. Measurements of Antenna Parameters in GTEM Cell

    OpenAIRE

    Živković, Zlatko; Šarolić, Antonio

    2010-01-01

    The paper presents the method for measuring parameters (gain, antenna factor, impedance and radiation pattern) of small antennas in GTEM cell, which is a novel method and environment for antenna measurements. In order to investigate the suitability of GTEM cell for this kind of measurement, the measurement results for a biconical dipole, microstrip patch antennas and small loop antenna were compared with those obtained by calibration inside fully absorber lined anechoic site, two-antenna meas...

  2. Design of LTCC Based Fractal Antenna

    KAUST Repository

    AdbulGhaffar, Farhan

    2010-09-01

    The thesis presents a Sierpinski Carpet fractal antenna array designed at 24 GHz for automotive radar applications. Miniaturized, high performance and low cost antennas are required for this application. To meet these specifications a fractal array has been designed for the first time on Low Temperature Co-fired Ceramic (LTCC) based substrate. LTCC provides a suitable platform for the development of these antennas due to its properties of vertical stack up and embedded passives. The complete antenna concept involves integration of this fractal antenna array with a Fresnel lens antenna providing a total gain of 15dB which is appropriate for medium range radar applications. The thesis also presents a comparison between the designed fractal antenna and a conventional patch antenna outlining the advantages of fractal antenna over the later one. The fractal antenna has a bandwidth of 1.8 GHz which is 7.5% of the centre frequency (24GHz) as compared to 1.9% of the conventional patch antenna. Furthermore the fractal design exhibits a size reduction of 53% as compared to the patch antenna. In the end a sensitivity analysis is carried out for the fractal antenna design depicting the robustness of the proposed design against the typical LTCC fabrication tolerances.

  3. Analysis of biconical microstrip antennas

    Science.gov (United States)

    Lin, Y.; Shafai, L.

    1992-12-01

    Biconical microstrip antennas having a conical patch over a conical substrate are investigated. Analytical expressions for the field distribution inside the conical cavity are developed in a spherical coordinate system and used to determine the eigenvalues of the resonant modes. It is found that, in addition to the axially symmetric modes, TE modes can also resonate which are asymmetric and dependent on the azimuthal angle. For coaxial probe excitation of the cavity its analytic expressions for the field components are determined and used to investigate the antenna input parameters and radiation patterns. The special case of a conical patch microstrip antenna with a planar substrate is also studied. It is shown that, in comparison with circular disk microstrip antennas, a conical patch yields a wider impedance bandwidth and higher gain.

  4. Multifrequency Printed Antennas Loaded with Metamaterial Particles

    Directory of Open Access Journals (Sweden)

    D. Segovia-Vargas

    2009-06-01

    Full Text Available This paper provides a review of printed antennas loaded with metamaterial particles. This novel technique allows developing printed antennas with interesting features such as multifrequency (simultaneous operation over two or more frequency bands and multifunctionality (e. g. radiation pattern diversity. Moreover, compactness is also achieved and the main advantages of conventional printed antennas (light weight, low profile, low cost ... are maintained. Different types of metamaterial-loaded printed antennas are reviewed: printed dipoles and patch antennas. Several prototypes are designed, manufactured and measured showing good results. Furthermore, simple but accurate equivalent models are proposed. These models allow an easy and quick design of metamaterial-loaded printed antennas. Finally, two interesting applications based on the proposed antennas are reviewed: the patch antennas are used as radiating elements of emerging active RFID systems in the microwave band and the metamaterial-loaded printed dipoles are employed to increase the performance of log-periodic arrays.

  5. Low Cost Antennas for Direct Broadcast Satellite Radio

    Science.gov (United States)

    Wu, T. K.; Huang, J.

    1994-01-01

    Two omni-directional and circularly polarized low gain antennas (the crossed drooping dipole and the TM(sub 21) mode circular patch antenna)are developed for direct broadcast satellite radio (DBSR) outdoor mobile terminal applications.

  6. Lightweight, Durable Army Antennas Using Carbon Nanotube Technology

    Science.gov (United States)

    2013-01-01

    12 Figure 17. X- band aperture-coupled patch antenna design...may be adjusted by collecting the sheet on a revolving substrate conveyor belt (e.g., Teflon belt), as shown in figure 15 (12). SEM images of the...the top surface. Figure 17. X- band aperture-coupled patch antenna design. A standard X- band aperture-coupled patch antenna design, previously

  7. Suspended microfluidics

    OpenAIRE

    Casavant, Benjamin P.; Berthier, Erwin; Theberge, Ashleigh B.; Jean BERTHIER; Montanez-Sauri, Sara I.; Bischel, Lauren L.; Brakke, Kenneth; Hedman, Curtis J.; Bushman, Wade; Keller, Nancy P.; Beebe, David J.

    2013-01-01

    Although the field of microfluidics has made significant progress in bringing new tools to address biological questions, the accessibility and adoption of microfluidics within the life sciences are still limited. Open microfluidic systems have the potential to lower the barriers to adoption, but the absence of robust design rules has hindered their use. Here, we present an open microfluidic platform, suspended microfluidics, that uses surface tension to fill and maintain a fluid in microscale...

  8. 47 CFR 80.863 - Antenna system.

    Science.gov (United States)

    2010-10-01

    ... MARITIME SERVICES Technical Equipment Requirements for Cargo Vessels Not Subject to Subpart W § 80.863... construction of the required antenna must insure operation in time of emergency. (b) If the required antenna is suspended between masts or other supports liable to whipping, a safety link which, under heavy stress, will...

  9. Proximity fed gap-coupled half E-shaped microstrip antenna array

    Indian Academy of Sciences (India)

    USA: Artech. Chair R, Mak C L, Lee K F, Luk K M and Kishk A A 2005 Miniaturized wide-bandhalf U-slot and half. E-shaped patch antennas. IEEE Transactions on Antennas and Propagation 53(8): 2645–2652. Cock R T and Christodoulou C G 1987 Design of a two layer capacitively coupled, microstrip patch antenna.

  10. Smart antennas

    CERN Document Server

    Godara, Lal Chand

    2004-01-01

    INTRODUCTION Antenna GainPhased Array AntennaPower Pattern Beam Steering Degree of Freedom Optimal AntennaAdaptive AntennaSmart AntennaSummary NARROWBAND PROCESSINGSignal Model Conventional BeamformerNull Steering BeamformerOptimal BeamformerOptimization Using Reference SignalBeam Space Processing Effect of ErrorsNotation and AbbreviationsReferencesADAPTIVE PROCESSINGSample Matrix Inversion AlgorithmUnconstrained Least Mean Squares AlgorithmNormalized Least Mean Squares AlgorithmConstrained

  11. Passive and active reconfigurable microstrip reflectarray antennas

    NARCIS (Netherlands)

    Hajian, M.

    2008-01-01

    Novel solutions for conceiving microstrip reflectarray antennas (MRA) using various types of patches are presented in this PhD thesis. The approach is based on the integration of a varactor diode active device into elementary hollow patch radiators. In the first part of the thesis, a new concept for

  12. Deployable antenna

    Science.gov (United States)

    Fink, Patrick W. (Inventor); Dobbins, Justin A. (Inventor); Lin, Greg Y. (Inventor); Chu, Andrew W. (Inventor); Scully, Robert C. (Inventor)

    2006-01-01

    A deployable antenna and method for using wherein the deployable antenna comprises a collapsible membrane having at least one radiating element for transmitting electromagnetic waves, receiving electromagnetic waves, or both.

  13. Feed Structure For Antennas

    Science.gov (United States)

    Fink, Patrick W. (Inventor); Chu, Andrew W. (Inventor); Dobbins, Justin A. (Inventor); Lin, Greg Y. (Inventor)

    2005-01-01

    A novel feed structure, for an antenna having a resonant electric field structure, comprising a patch element, an integrated circuit attached to the patch element, at least one inner conductor electrically connected to and terminating at the integrated circuit on a first end of the at least one inner conductor, wherein the at least one inner conductor extends through and is not electrically connected to the patch element, and wherein the at least one inner conductor is available for electrical connectivity on a second end of the at least one inner conductor, and an outer conductor electrically connected to and terminating at the patch element on a first end of the outer conductor, wherein the outer conductor is available for electrical connectivity on a second end of the outer conductor, and wherein the outer conductor concentrically surrounds the at least one inner conductor from the second end of the at least one inner conductor available for electrical connectivity to the first end of the outer conductor terminating at the patch element.

  14. A Compact Design of Planar Array Antenna with Fractal Elements for Future Generation Applications

    DEFF Research Database (Denmark)

    Ojaroudiparchin, Naser; Shen, Ming; Pedersen, Gert F.

    2016-01-01

    In this paper, a planar phased array fractal antenna for the future fifth generation (5G) applications is presented. The proposed array antenna is designed to operate at 22 GHz. 64 patch antenna elements with coaxial-probe feeds have been used for the proposed design. The antenna elements are based...

  15. Vertical Meandering Approach for Antenna Size Reduction

    Directory of Open Access Journals (Sweden)

    Li Deng

    2012-01-01

    Full Text Available A novel vertical meandering technique to reduce the lateral size of a planar printed antenna is presented. It is implemented by dividing a conventional spiral patch into a different number of segments and placing them on different sides of the microwave substrate with vias as the connections. To confirm the validity of this technique, measured electrical performance and radiation characteristics of five antennas with different numbers of segments are compared. The smallest antenna is reduced in size by 84% when compared with the conventional printed spiral antenna.

  16. Considerations for millimeter wave printed antennas

    Science.gov (United States)

    Pozar, D. M.

    1983-01-01

    Calculated data are presented on the performance of printed antenna elements on substrates which may be electrically thick, as would be the case for printed antennas at millimeter wave frequencies. Printed dipoles and microstrip patch antennas on polytetrafluoroethylene (PTFE), quartz, and gallium arsenide substrates are considered. Data are given for resonant length, resonant resistance, bandwidth, loss due to surface waves, loss due to dielectric heating, and mutual coupling. Also presented is an optimization procedure for maximizing or minimizing power launched into surface waves from a multielement printed antenna array. The data are calculated by a moment method solution.

  17. Design, analysis and control of cable-suspended parallel robots and its applications

    CERN Document Server

    Zi, Bin

    2017-01-01

    This book provides an essential overview of the authors’ work in the field of cable-suspended parallel robots, focusing on innovative design, mechanics, control, development and applications. It presents and analyzes several typical mechanical architectures of cable-suspended parallel robots in practical applications, including the feed cable-suspended structure for super antennae, hybrid-driven-based cable-suspended parallel robots, and cooperative cable parallel manipulators for multiple mobile cranes. It also addresses the fundamental mechanics of cable-suspended parallel robots on the basis of their typical applications, including the kinematics, dynamics and trajectory tracking control of the feed cable-suspended structure for super antennae. In addition it proposes a novel hybrid-driven-based cable-suspended parallel robot that uses integrated mechanism design methods to improve the performance of traditional cable-suspended parallel robots. A comparative study on error and performance indices of hybr...

  18. Antenna toolkit

    CERN Document Server

    Carr, Joseph

    2006-01-01

    Joe Carr has provided radio amateurs and short-wave listeners with the definitive design guide for sending and receiving radio signals with Antenna Toolkit 2nd edition.Together with the powerful suite of CD software, the reader will have a complete solution for constructing or using an antenna - bar the actual hardware! The software provides a simple Windows-based aid to carrying out the design calculations at the heart of successful antenna design. All the user needs to do is select the antenna type and set the frequency - a much more fun and less error prone method than using a con

  19. Compact Miniaturized Antenna for 210 MHz RFID

    Science.gov (United States)

    Lee, Richard Q.; Chun, Kue

    2008-01-01

    This paper describes the design and simulation of a miniaturized square-ring antenna. The miniaturized antenna, with overall dimensions of approximately one tenth of a wavelength (0.1 ), was designed to operate at around 210 MHz, and was intended for radio-frequency identification (RFID) application. One unique feature of the design is the use of a parasitic element to improve the performance and impedance matching of the antenna. The use of parasitic elements to enhance the gain and bandwidth of patch antennas has been demonstrated and reported in the literature, but such use has never been applied to miniaturized antennas. In this work, we will present simulation results and discuss design parameters and their impact on the antenna performance.

  20. A New Metasurface Superstrate Structure for Antenna Performance Enhancement.

    Science.gov (United States)

    Islam, Mohammad Tariqul; Ullah, Mohammad Habib; Singh, Mandeep Jit; Faruque, Mohammad Rashed Iqbal

    2013-07-31

    A new metasurface superstrate structure (MSS)-loaded dual band microstrip line-fed small patch antenna is presented in this paper. The proposed antenna was designed on a ceramic-filled bioplastic sandwich substrate with a high dielectric constant. The proposed 7 × 6 element, square-shaped, single-sided MSS significantly improved the bandwidth and gain of the proposed antenna. The proposed MSS incorporated a slotted patch antenna that effectively increased the measured operating bandwidth from 13.3% to 18.8% and from 14.8% to 23.2% in the lower and upper bands, respectively. Moreover, the average gain of the proposed MSS-based antenna was enhanced from 2.12 dBi to 3.02 dBi in the lower band and from 4.10 dBi to 5.28 dBi in the upper band compared to the patch antenna alone. In addition to the bandwidth and gain improvements, more directive radiation characteristics were also observed from the MSS antenna compared to the patch itself. The effects of the MSS elements and the ground plane length on the reflection coefficient of the antenna were analyzed and optimized. The overall performance makes the proposed antenna appropriate for RFID and WLAN applications.

  1. A New Metasurface Superstrate Structure for Antenna Performance Enhancement

    Directory of Open Access Journals (Sweden)

    Mohammad Rashed Iqbal Faruque

    2013-07-01

    Full Text Available A new metasurface superstrate structure (MSS-loaded dual band microstrip line-fed small patch antenna is presented in this paper. The proposed antenna was designed on a ceramic-filled bioplastic sandwich substrate with a high dielectric constant. The proposed 7 × 6 element, square-shaped, single-sided MSS significantly improved the bandwidth and gain of the proposed antenna. The proposed MSS incorporated a slotted patch antenna that effectively increased the measured operating bandwidth from 13.3% to 18.8% and from 14.8% to 23.2% in the lower and upper bands, respectively. Moreover, the average gain of the proposed MSS-based antenna was enhanced from 2.12 dBi to 3.02 dBi in the lower band and from 4.10 dBi to 5.28 dBi in the upper band compared to the patch antenna alone. In addition to the bandwidth and gain improvements, more directive radiation characteristics were also observed from the MSS antenna compared to the patch itself. The effects of the MSS elements and the ground plane length on the reflection coefficient of the antenna were analyzed and optimized. The overall performance makes the proposed antenna appropriate for RFID and WLAN applications.

  2. Buprenorphine Transdermal Patch

    Science.gov (United States)

    Buprenorphine patches are used to relieve severe pain in people who are expected to need pain medication ... Transdermal buprenorphine comes as a patch to apply to the skin. The patch is usually applied to the skin ...

  3. Acoustically actuated ultra-compact NEMS magnetoelectric antennas.

    Science.gov (United States)

    Nan, Tianxiang; Lin, Hwaider; Gao, Yuan; Matyushov, Alexei; Yu, Guoliang; Chen, Huaihao; Sun, Neville; Wei, Shengjun; Wang, Zhiguang; Li, Menghui; Wang, Xinjun; Belkessam, Amine; Guo, Rongdi; Chen, Brian; Zhou, James; Qian, Zhenyun; Hui, Yu; Rinaldi, Matteo; McConney, Michael E; Howe, Brandon M; Hu, Zhongqiang; Jones, John G; Brown, Gail J; Sun, Nian Xiang

    2017-08-22

    State-of-the-art compact antennas rely on electromagnetic wave resonance, which leads to antenna sizes that are comparable to the electromagnetic wavelength. As a result, antennas typically have a size greater than one-tenth of the wavelength, and further miniaturization of antennas has been an open challenge for decades. Here we report on acoustically actuated nanomechanical magnetoelectric (ME) antennas with a suspended ferromagnetic/piezoelectric thin-film heterostructure. These ME antennas receive and transmit electromagnetic waves through the ME effect at their acoustic resonance frequencies. The bulk acoustic waves in ME antennas stimulate magnetization oscillations of the ferromagnetic thin film, which results in the radiation of electromagnetic waves. Vice versa, these antennas sense the magnetic fields of electromagnetic waves, giving a piezoelectric voltage output. The ME antennas (with sizes as small as one-thousandth of a wavelength) demonstrates 1-2 orders of magnitude miniaturization over state-of-the-art compact antennas without performance degradation. These ME antennas have potential implications for portable wireless communication systems.The miniaturization of antennas beyond a wavelength is limited by designs which rely on electromagnetic resonances. Here, Nan et al. have developed acoustically actuated antennas that couple the acoustic resonance of the antenna with the electromagnetic wave, reducing the antenna footprint by up to 100.

  4. Flexible three-dimensional printed antenna substrates

    Directory of Open Access Journals (Sweden)

    Syed Sheheryar Bukhari

    2015-08-01

    Full Text Available Flexible heterogeneous substrates have been constructed, using three-dimensional printing in a single process, by introducing air-filled slots. These substrates have been used to substantially reduce the substrate losses for a flexible microstrip patch antenna causing an increase in its radiation efficiency. By combining transverse magnetic (TM10 and TM01 modes the bandwidth of this antenna has also been increased.

  5. Closely Mounted Compact Wideband Diversity Antenna for Mobile Phone Applications

    Directory of Open Access Journals (Sweden)

    Bunggil Yu

    2012-01-01

    Full Text Available Here a compact wideband diversity antenna covering the PCS/UMTS/WiMAX bands with high isolation and low enveloped correlation coefficient (ECC is proposed. To widen the bandwidth, the proposed antenna uses a structure with a gap-coupled feed and an inductively shorted line that has capacitive compensation between the radiator and the ground plane. Also, a suspended line with a parasitic element is used to enhance the isolation between the two antennas.

  6. Planar Tri-Band Antenna Design

    Directory of Open Access Journals (Sweden)

    M. Pokorny

    2008-04-01

    Full Text Available The paper briefly uncovers techniques used for a design of compact planar antennas in order to achieve the wideband and the multi-band capability. The main topic is aimed to the multi-objective optimization using genetic algorithms. A quarter-wavelength planar inverted-F antenna (PIFA using a slot and shorted parasitic patches is chosen to cover GSM900, GSM1800 and ISM2400 bands. A global multi-objective optimization uses a binary genetic algorithm with a composite objective function to tune this antenna. The impedance match and the direction of maximum gain are desired parameters to improve.

  7. Scalable Notch Antenna System for Multiport Applications

    Directory of Open Access Journals (Sweden)

    Abdurrahim Toktas

    2016-01-01

    Full Text Available A novel and compact scalable antenna system is designed for multiport applications. The basic design is built on a square patch with an electrical size of 0.82λ0×0.82λ0 (at 2.4 GHz on a dielectric substrate. The design consists of four symmetrical and orthogonal triangular notches with circular feeding slots at the corners of the common patch. The 4-port antenna can be simply rearranged to 8-port and 12-port systems. The operating band of the system can be tuned by scaling (S the size of the system while fixing the thickness of the substrate. The antenna system with S: 1/1 in size of 103.5×103.5 mm2 operates at the frequency band of 2.3–3.0 GHz. By scaling the antenna with S: 1/2.3, a system of 45×45 mm2 is achieved, and thus the operating band is tuned to 4.7–6.1 GHz with the same scattering characteristic. A parametric study is also conducted to investigate the effects of changing the notch dimensions. The performance of the antenna is verified in terms of the antenna characteristics as well as diversity and multiplexing parameters. The antenna system can be tuned by scaling so that it is applicable to the multiport WLAN, WIMAX, and LTE devices with port upgradability.

  8. Study on Horizontally Polarized Omnidirectional Microstrip Antenna

    Directory of Open Access Journals (Sweden)

    Kun Wei

    2016-01-01

    Full Text Available A horizontally polarized omnidirectional microstrip antenna is proposed in this paper. The structure of designed antenna is with two back-to-back horizontally polarized microstrip antenna elements. Gain variation on main radiation plane of this new antenna is analyzed and radiation theory is deduced; formula of directivity on main radiation plane is given. Better omnidirectional characteristic of this antenna can be obtained by decreasing patch physical length. Both simulated and measured results verify the omnidirectional radiation patterns and input impedance characteristics. Good omnidirectional radiation patterns (gain variation in E-plane less than ±0.4 dBi and input impedance characteristics are obtained; moreover, cross polarization less than −20 dBi is achieved.

  9. 5G antenna array with wide-angle beam steering and dual linear polarizations

    KAUST Repository

    Klionovski, Kirill

    2017-10-25

    In this paper, we present the design of a switched-beam antenna array at millimeter-wave frequencies for future 5G applications. The proposed antenna array is based on wideband patch antenna elements and a Butler matrix feed network. The patch antenna has a broad radiation pattern for wide-angle beam steering and allows the simultaneous operation with two orthogonal linear polarizations. A combination of two separated Butler matrices provides independent beam steering for both polarizations in the wide operating band. The antenna array has a simple multilayer construction, and it is made on a low-cost Rogers laminate.

  10. Stretchable and reversibly deformable radio frequency antennas based on silver nanowires.

    Science.gov (United States)

    Song, Lingnan; Myers, Amanda C; Adams, Jacob J; Zhu, Yong

    2014-03-26

    We demonstrate a class of microstrip patch antennas that are stretchable, mechanically tunable, and reversibly deformable. The radiating element of the antenna consists of highly conductive and stretchable material with screen-printed silver nanowires embedded in the surface layer of an elastomeric substrate. A 3-GHz microstrip patch antenna and a 6-GHz 2-element patch array are fabricated. Radiating properties of the antennas are characterized under tensile strain and agree well with the simulation results. The antenna is reconfigurable because the resonant frequency is a function of the applied tensile strain. The antenna is thus well suited for applications like wireless strain sensing. The material and fabrication technique reported here could be extended to achieve other types of stretchable antennas with more complex patterns and multilayer structures.

  11. Recent activities in printed Antennas at LeRC

    Science.gov (United States)

    Lee, Richard Q.; Simons, Rainee N.

    1993-01-01

    This paper will report two recent R&D efforts in printed antennas at NASA Lewis Research Center. These efforts are: (1) to enhance the current antenna performance in gain, bandwidth and pattern characteristics, and (2) to develop coplanar waveguide/aperture coupled feeding technique for dual excitation of a patch antenna. Research in area (1) has led to the development of a nonplanar linearly tapered slot antenna (LTSA) which has exhibited over 10 dB gain with broad bandwidth and excellent radiation patterns. This endfire antenna element is most suitable for use in MMIC arrays of 'brick' construction. A space power amplifier composed of active LTSA has been demonstrated and shown to have a gain of 30 dB at 20 GHz. In each of the antenna elements, a GaAs monolithic microwave integrated circuit (MMIC) three-stage power amplifier is integrated with two LTSA's. A single active LTSA has also been demonstrated and exhibited a power gain of 6.7 dB with the MMIC amplifier turned on. The aperture coupled feeding technique with coplanar waveguide feeds has demonstrated high coupling efficiency on both LTSA and patch antennas. Recent efforts have been focused on applying this technique for dual excitation (dual frequency and/or dual polarization) of a patch antenna. Preliminary results confirm the feasibility of this approach. Further development is required to improve the coupling efficiency and antenna radiation characteristics.

  12. Microstrip Antenna for Remote Sensing of Soil Moisture and Sea Surface Salinity

    Science.gov (United States)

    Ramhat-Samii, Yahya; Kona, Keerti; Manteghi, Majid; Dinardo, Steven; Hunter, Don; Njoku, Eni; Wilson, Wiliam; Yueh, Simon

    2009-01-01

    This compact, lightweight, dual-frequency antenna feed developed for future soil moisture and sea surface salinity (SSS) missions can benefit future soil and ocean studies by lowering mass, volume, and cost of the antenna system. It also allows for airborne soil moisture and salinity remote sensors operating on small aircraft. While microstrip antenna technology has been developed for radio communications, it has yet to be applied to combined radar and radiometer for Earth remote sensing. The antenna feed provides a key instrument element enabling high-resolution radiometric observations with large, deployable antennas. The design is based on the microstrip stacked-patch array (MSPA) used to feed a large, lightweight, deployable, rotating mesh antenna for spaceborne L-band (approximately equal to 1 GHz) passive and active sensing systems. The array consists of stacked patches to provide dual-frequency capability and suitable radiation patterns. The stacked-patch microstrip element was designed to cover the required L-band center frequencies at 1.26 GHz (lower patch) and 1.413 GHz (upper patch), with dual-linear polarization capabilities. The dimension of patches produces the required frequencies. To achieve excellent polarization isolation and control of antenna sidelobes for the MSPA, the orientation of each stacked-patch element within the array is optimized to reduce the cross-polarization. A specialized feed-distribution network was designed to achieve the required excitation amplitude and phase for each stacked-patch element.

  13. Suspended chains damp wind-induced oscillations of tall flexible structures

    Science.gov (United States)

    Reed, W. H., III

    1968-01-01

    Hanging-chain system, which is a form of impact damper, suppresses wind-induced bending oscillations of tall cylindrical antenna masts. A cluster of chains enclosed in a neoprene shroud is suspended inside the tip of the antenna mast, forming a simple method of damping structural vibrations.

  14. Antenna theory and practice

    Science.gov (United States)

    Chatterjee, Rajeswari

    The fundamental operating principles and applications of antennas are examined in an introductory textbook for undergraduate engineering students. The theory of EM fields and radiation is reviewed, and consideration is given to thin linear, cylindrical, and biconical antennas; antenna arrays; loop, helical, slot, microstrip, horn, reflector, and lens antennas; leaky-wave and surface-wave antennas; dielectric and dielectric-loaded metallic antennas; and wideband antennas. Also discussed are antenna synthesis, practical antennas for different wavebands, antenna measurements, EM wave propagation, and problems in antenna design. Diagrams, drawings, graphs, and sample problems are provided.

  15. Microwave-induced nonequilibrium temperature in a suspended carbon nanotube

    NARCIS (Netherlands)

    Hortensius, H.L.; Öztürk, A.; Zeng, P.; Driessen, E.F.C.; Klapwijk, T.M.

    2012-01-01

    Antenna-coupled suspended single carbon nanotubes exposed to 108?GHz microwave radiation are shown to be selectively heated with respect to their metal contacts. This leads to an increase in the conductance as well as to the development of a power-dependent DC voltage. The increased conductance

  16. Comparative Study of Antenna Designs for RF Energy Harvesting

    Directory of Open Access Journals (Sweden)

    Sika Shrestha

    2013-01-01

    Full Text Available In the last few years, several antenna designs of rectenna that meet various objectives have been proposed for use in RF energy harvesting. Among various antennas, microstrip patch antennas are widely used because of their low profile, light weight, and planar structure. Conventional patch antennas are rectangular or circular in shape, but variations in their basic design are made for different purposes. This paper begins with an explanation and discussion of different designs, put forward with an aim of miniaturization, harmonic rejection, and reconfigurability. Finally, microstrip patch structured rectennas are evaluated and compared with an emphasis on the various methods adopted to obtain a compact rectenna, harmonic rejection functionality, and frequency and polarization selectivity.

  17. A Frequency Reconfigurable MIMO Antenna System for Cognitive Radio Applications

    Science.gov (United States)

    Raza, A.; Khan, Muhammad U.; Tahir, Farooq A.

    2017-10-01

    In this paper, a two element frequency reconfigurable multiple-input-multiple-output (MIMO) antenna system is presented. The proposed antenna consists of miniaturized patch antenna elements, loaded with varactor diodes to achieve frequency reconfigurability. The antenna has bandwidth of 30 MHz and provides a smooth frequency sweep from 2.12 GHz to 2.4 GHz by varying the reverse bias voltage of varactor diode. The antenna is designed on an FR4 substrate and occupies a space of 50×100 × 0.8 mm3. The antenna is analyzed for its far-field characteristics as well as for MIMO performance parameters. Designed antenna showed good performance and is suitable for cognitive radios (CR) applications.

  18. Miniaturized Circularly Polarized Microstrip RFID Antenna Using Fractal Metamaterial

    Directory of Open Access Journals (Sweden)

    Guo Liu

    2013-01-01

    Full Text Available A novel miniaturized circularly polarized (CP microstrip antenna that can handle UHF band (920–925 MHz, corresponding to the assigned band for RFID in China has been designed, fabricated, and measured in this paper. The miniaturization of antenna is achieved by a special cross-shaped fractal metamaterial structure that is inserted between the patch and ground plane. The measured results show that the antenna possesses an impedance bandwidth of 8.7% with VSWR 1.5 : 1 and 3-dB axial bandwidth of 3.8%. Furthermore, the proposed antenna has 10.2% size reduction compared with traditional patch antenna. The tested results are in good agreement with that of the simulations.

  19. Design of a Microstrip Bowtie Antenna for Indoor Radio-Communications

    OpenAIRE

    Fraga-Rosales Hector; Reyes-Ayala Mario; Hernandez-Valdez Genaro; Andrade-Gonzalez Edgar Alejandro; Miranda-Tello Jose Raul; Cruz-Perez Felipe Alejandro; Castellanos-Lopez Sandra Lirio

    2017-01-01

    In this paper, a microstrip bowtie patch antenna (MBPA) for wireless indoor communications is carried out. Here, a microstrip transmission-line feed network was designed in order to match the MBPA. The proposed antenna uses a ground plane with the aim of narrowing down the back lobes in comparison with bowtie sheet antennas, which radiation pattern is omni-directional. The far-field pattern of the antenna was simulated using a finite-element numerical algorithm and obtained by interpolation e...

  20. Particle Swarm Optimization for Multiband Metamaterial Fractal Antenna

    Directory of Open Access Journals (Sweden)

    Balamati Choudhury

    2013-01-01

    Full Text Available The property of self-similarity, recursive irregularity, and space filling capability of fractal antennas makes it useful for various applications in wireless communication, including multiband miniaturized antenna designs. In this paper, an effort has been made to use the metamaterial structures in conjunction with the fractal patch antenna, which resonates at six different frequencies covering both C and X band. Two different types of square SRR are loaded on the fractal antenna for this purpose. Particle swarm optimization (PSO is used for optimization of these metamaterial structures. The optimized metamaterial structures, after loading upon, show significant increase in performance parameters such as bandwidth, gain, and directivity.

  1. DUAL POLARIZATION ANTENNA ARRAY WITH VERY LOW CROSS POLARIZATION AND LOW SIDE LOBES

    DEFF Research Database (Denmark)

    1997-01-01

    The present invention relates to an antenna array adapted to radiate or receive electromagnetic waves of one or two polarizations with very low cross polarization and low side lobes. An antenna array comprising many antenna elements, e.g. more than ten antenna elements, is provided in which...... formation of grating lobes are inhibited in selected directions of the radiation and cross polarization within the main lobe is suppressed at least 30 dB below the main lobe peak value. According to a preferred embodiment of the invention, the antenna elements of the antenna array comprise probe-fed patches...

  2. The RF Energy Harvesting Antennas Operating in Commercially Deployed Frequency Bands: A Comparative Study

    Directory of Open Access Journals (Sweden)

    M. Mrnka

    2016-01-01

    Full Text Available This paper deals with suitable antennas for energy harvesting, which is a growing research field due to the utilization of nowadays ubiquitous and abundant RF energy. Four types of basic antenna structures suitable for harvesting applications, namely, the patch antenna, slot antenna, modified inverted F antenna, and dielectric resonator antenna, are compared from the viewpoint of reflection coefficient, efficiency, radiation patterns, and dimensions. The frequencies of interest were chosen so that they cover several main wireless systems operating between 0.8 GHz and 2.6 GHz, that is, GSM, UMTS, and WiFi.

  3. modified edge fed sierpinski carpet miniaturized microstrip patch ...

    African Journals Online (AJOL)

    user

    2016-07-03

    Jul 3, 2016 ... Compact circularly polarized rectenna with unbalanced circular slots was proposed by Y.O et al. 12% size reduction was achieved by reducing the radius of rectenna from 16.5 mm to 15.5 mm [10]. By using the asymmetric slit to reduce the size of a square patch antenna, 40% size reduction was achieved ...

  4. Optimization of Planar Monopole Wideband Antenna for Wireless Communication System.

    Science.gov (United States)

    Shakib, Mohammed Nazmus; Moghavvemi, Mahmoud; Mahadi, Wan Nor Liza

    2016-01-01

    In this paper, a new compact wideband monopole antenna is presented for wireless communication applications. This antenna comprises of a new radiating patch, a new arc-shaped strip, microstrip feed line, and a notched ground plane. The proposed radiating patch is combined with a rectangular and semi-circular patch and is integrated with a partial ground plane to provide a wide impedance bandwidth. The new arc-shaped strip between the radiating patch and microstrip feed line creates an extra surface on the patch, which helps further widen the bandwidth. Inserting one step notch on the ground plane further enhances the bandwidth. The antenna has a compact size of 16×20×1.6mm3. The measured result indicated that the antenna achieves a 127% bandwidth at VSWR≤2, ranging from 4.9GHz to 22.1GHz. Stable radiation patterns with acceptable gain are achieved. Also, a measured bandwidth of 107.7% at VSWR≤1.5 (5.1-17GHz) is obtained, which is suitable for UWB outdoor propagation. This antenna is compatible with a good number of wireless standards, including UWB band, Wimax 5.4 GHz band, MVDDS (12.2-12.7GHz), and close range radar and satellite communication in the X-band (8-12GHz), and Ku band (12-18GHz).

  5. Superluminal antenna

    Energy Technology Data Exchange (ETDEWEB)

    Singleton, John; Earley, Lawrence M.; Krawczyk, Frank L.; Potter, James M.; Romero, William P.; Wang, Zhi-Fu

    2017-03-28

    A superluminal antenna element integrates a balun element to better impedance match an input cable or waveguide to a dielectric radiator element, thus preventing stray reflections and consequent undesirable radiation. For example, a dielectric housing material can be used that has a cutout area. A cable can extend into the cutout area. A triangular conductor can function as an impedance transition. An additional cylindrical element functions as a sleeve balun to better impedance match the radiator element to the cable.

  6. A Study on the RF-DC Conversion Efficiency of Microstrip Patch Rectenna

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yang Ha; Youn, Dong Gi; Kim, Kwan Ho [Korea Electrotechnology Research Institute (Korea); Rhee, Young Chul [Kyungnam University (Korea)

    2000-07-01

    We designed and manufactured microstrip patch antenna mainly used in the rectenna and then analysed RF-DC conversion efficiency of wireless power transmission system. We analyse conversion efficiency of load, direction of linear and dual polization rectenna. We found that the maximum efficiency would be about 70% of load and direction in patch type. In conclusion, we found that total conversion efficiency is 64% - 71% in patch Rectenna. (author). 5 refs., 8 figs., 1 tab.

  7. Investigation of microwave antennas with improved performances

    Science.gov (United States)

    Zhou, Rongguo

    This dissertation presents the investigation of antennas with improved performances at microwave frequencies. It covers the following three topics: the study of the metamaterial with near-zero index of refraction and its application in directive antenna design, the design technique of a wideband circularly polarized patch antenna for 60GHz wireless application and the investigation of a novel direction of arrival (DOA) estimation technique inspired by human auditory system. First, the metamaterial composed of two-dimensional (2-D) metallic wire arrays is investigated as an effective medium with an effective index of refraction less than unity (neff MUSIC) algorithm is applied to calculate the DOA. The improved estimation accuracy is demonstrated in both simulation and experiment. Furthermore, inspired by the sound localization capability of human using just a single ear, a novel direction of arrival estimation technique using a single UWB antenna is proposed and studied. The DOA estimation accuracies of the single UWB antenna are studied in the x-y, x-z and y-z planes with different Signal to Noise Ratios (SNR). The proposed single antenna DOA technique is demonstrated in both simulation and experiment, although with reduced accuracy comparing with the case of two antennas with a scatter in between. At the end, the conclusions of this dissertation are drawn and possible future works are discussed.

  8. Design of silicon-based fractal antennas

    KAUST Repository

    Ghaffar, Farhan A.

    2012-11-20

    This article presents Sierpinski carpet fractal antennas implemented in conventional low resistivity (Ï =10 Ω cm) as well as high resistivity (Ï =1500 Ω cm) silicon mediums. The fractal antenna is 36% smaller as compared with a typical patch antenna at 24 GHz and provides 13% bandwidth on high resistivity silicon, suitable for high data rate applications. For the first time, an on-chip fractal antenna array is demonstrated in this work which provides double the gain of a single fractal element as well as enhanced bandwidth. A custom test fixture is utilized to measure the radiation pattern and gain of these probe-fed antennas. In addition to gain and impedance characterization, measurements have also been made to study intrachip communication through these antennas. The comparison between the low resistivity and high resistivity antennas indicate that the former is not a suitable medium for array implementation and is only suitable for short range communication whereas the latter is appropriate for short and medium range wireless communication. The design is well-suited for compact, high data rate System-on-Chip (SoC) applications as well as for intrachip communication such as wireless global clock distribution in synchronous systems. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:180-186, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27245 Copyright © 2012 Wiley Periodicals, Inc.

  9. Metamaterial Inspired Microstrip Antenna Investigations Using Metascreens

    Directory of Open Access Journals (Sweden)

    Muhammad Tauseef Asim

    2015-01-01

    Full Text Available A dual layer periodically patterned metamaterial inspired antenna on a low cost FR4 substrate is designed, simulated, fabricated, and tested. The eigenmode dispersion simulations are performed indicating the left handed metamaterial characteristics and are tunable with substrate permittivity. The same metamaterial unit cell structure is utilized to fabricate a metascreen. This metascreen is applied below the proposed metamaterial antenna and next used as superstrate above a simple patch to study the effects on impedance bandwidth, gain, and radiation patterns. The experimental results of these antennas are very good and closely match with the simulations. More importantly, the resonance for the proposed metamaterial antenna with metascreen occurs at the left handed (LH eigenfrequency of the metamaterial unit cell structure. The measured −10 dB bandwidths are 14.56% and 22.86% for the metamaterial antenna with single and double metascreens, respectively. The metascreens over the simple patch show adjacent dual band response. The first and second bands have measured −10 dB bandwidths of 9.6% and 16.66%. The simulated peak gain and radiation efficiency are 1.83 dBi and 74%, respectively. The radiation patterns are also very good and could be useful in the UWB wireless applications.

  10. High-T{sub c} superconducting rectangular microstrip patch covered with a dielectric layer

    Energy Technology Data Exchange (ETDEWEB)

    Bedra, Sami, E-mail: s_bedra@yahoo.fr [Department of Industrial Engineering, University of Khenchela, 40004 Khenchela (Algeria); Fortaki, Tarek [Electronics Department, University of Batna, 05000 Batna (Algeria)

    2016-05-15

    Highlights: • We model a microstrip antenna with a dielectric cover and superconductor patch. • The extended full-wave analysis is used to solve for the antenna characteristics • The accuracy of the method is checked by comparing our results with published data • The superconducting patch affects the resonant characteristics of the antennaPatch on substrate–superstrate configuration is more advantageous than the one on single layer. - Abstract: This paper presents a full-wave method to calculate the resonant characteristics of rectangular microstrip antenna with and without dielectric cover, to explain the difference of performance with temperature between superconducting and normal conducting antenna. Especially the characteristics of high temperature superconducting (HTS) antenna were almost ideal around the critical temperature (T{sub c}). The dyadic Green's functions of the considered structure are efficiently determined in the vector Fourier transform domain. The effect of the superconductivity of the patch is taken into account using the concept of the complex resistive boundary condition. The computed results are found to be in good agreement with results obtained using other methods. Also, the effects of the superstrate on the resonant frequency and bandwidth of rectangular microstrip patch in a substrate–superstrate configuration are investigated. This type of configuration can be used for wider bandwidth by proper selection of superstrate thickness and its dielectric constants.

  11. Meandered-line antenna with integrated high-impedance surface.

    Energy Technology Data Exchange (ETDEWEB)

    Forman, Michael A.

    2010-09-01

    A reduced-volume antenna composed of a meandered-line dipole antenna over a finite-width, high-impedance surface is presented. The structure is novel in that the high-impedance surface is implemented with four Sievenpiper via-mushroom unit cells, whose area is optimized to match the meandered-line dipole antenna. The result is an antenna similar in performance to patch antenna but one fourth the area that can be deployed directly on the surface of a conductor. Simulations demonstrate a 3.5 cm ({lambda}/4) square antenna with a bandwidth of 4% and a gain of 4.8 dBi at 2.5 GHz.

  12. Frequency selective surfaces based high performance microstrip antenna

    CERN Document Server

    Narayan, Shiv; Jha, Rakesh Mohan

    2016-01-01

    This book focuses on performance enhancement of printed antennas using frequency selective surfaces (FSS) technology. The growing demand of stealth technology in strategic areas requires high-performance low-RCS (radar cross section) antennas. Such requirements may be accomplished by incorporating FSS into the antenna structure either in its ground plane or as the superstrate, due to the filter characteristics of FSS structure. In view of this, a novel approach based on FSS technology is presented in this book to enhance the performance of printed antennas including out-of-band structural RCS reduction. In this endeavor, the EM design of microstrip patch antennas (MPA) loaded with FSS-based (i) high impedance surface (HIS) ground plane, and (ii) the superstrates are discussed in detail. The EM analysis of proposed FSS-based antenna structures have been carried out using transmission line analogy, in combination with the reciprocity theorem. Further, various types of novel FSS structures are considered in desi...

  13. Quad-Band U-Slot Antenna for Mobile Applications

    Directory of Open Access Journals (Sweden)

    R. L. Ruiz

    2006-06-01

    Full Text Available In this paper, two different planar quad-band antennas are designed, modeled, fabricated and measured. Subsequently, the antennas are redesigned using an electromagnetic band gap substrate (EBG. Those new planar antennas operate in four frequency bands: 900 MHz, 1 800 MHz (both GSM, 1 900 MHz (USA and 2 400 to 2 500 MHz (Bluetooth The antenna has four narrow U-shaped slots etched to the patch. Using software, CST Microwave Studio [1], Zeland IE3D [2], and FEMLAB [3], simulations have been carried out to investigate the antenna's performance and characteristics. The antennas designed have been also built and measured to compare the real results with those obtained from the simulations.

  14. Investigation of Flexible Textile Antennas and AMC Reflectors

    Directory of Open Access Journals (Sweden)

    M. Mantash

    2012-01-01

    Full Text Available In this paper, two different methods for fabric characterization are presented: a single frequency method and a broadband method. Felt and denim fabrics are characterized, and patch antennas are designed using these substrates to test both methods. Prototypes of the antennas on felt and denim are manufactured using conductive textile (called electrotextile aiming to obtain fully flexible antennas. The prototypes are characterized in anechoic chamber to be compared and obtain conclusions related to the characterization methods. A new dual-band hexagonal AMC reflector combinable with antennas is also proposed to improve their performance and reduce the backward radiation to the human body. A novel broadband CPW-fed monopole antenna is designed to be combined with the AMC. The resulted prototype is characterized and compared with the performance of the CPW-fed antenna alone.

  15. Radiation Bandwidth Improvement of Electromagnetic Band Gap Cavity Antenna

    Science.gov (United States)

    Chaabane, Abdelhalim; Djahli, Farid; Attia, Hussein; Denidni, Tayeb. A.

    2017-05-01

    In this paper, an electromagnetic band gap cavity antenna with improved radiation and impedance bandwidths is presented. The proposed antenna is constructed by placing a triple-layer heterogeneous printed-unprinted partially reflective surface (PRS) above a primary aperture-coupled patch antenna. The PRS unit-cell provides a positive gradient reflection phase behavior over the desired frequency range. A prototype antenna is fabricated and measured that highlighted its ability to achieve 3-dB gain bandwidth of about 35.9 %, from 7.93 GHz to 11.4 GHz, with a peak gain of 14.25 dBi at 8.5 GHz. In addition, the impedance bandwidth is 40.32 %, from 7.9 GHz to 11.89 GHz. Thus, the designed antenna outperforms many other competitors for improving the radiation bandwidth of planar antennas with the same presented concept.

  16. Antennas in inhomogeneous media

    CERN Document Server

    Galejs, Janis; Fock, V A; Wait, J R

    2013-01-01

    Antennas in Inhomogeneous Media details the methods of analyzing antennas in such inhomogeneous media. The title covers the complex geometrical configurations along with its variational formulations. The coverage of the text includes various conditions the antennas are subjected to, such as antennas in the interface between two media; antennas in compressible isotropic plasma; and linear antennas in a magnetoionic medium. The selection also covers insulated loops in lossy media; slot antennas with a stratified dielectric or isotropic plasma layers; and cavity-backed slot antennas. The book wil

  17. Birth Control Patch

    Science.gov (United States)

    ... that use hormones, such as the birth control pill or birth control ring , a girl uses the birth control patch based on her monthly menstrual cycle. She puts on the patch on the first day of her menstrual cycle or the first Sunday after her menstrual cycle begins. She will change the ...

  18. Nitroglycerin Transdermal Patch

    Science.gov (United States)

    ... not go away after a short time. Nitroglycerin patches may no longer work as well after you have used them for ... times or the way that you apply nitroglycerin patches to avoid headaches because then the medication may not work as well. Your doctor may tell you to ...

  19. Estradiol Transdermal Patch

    Science.gov (United States)

    ... of estradiol patches to the breasts or to skin that is oily, damaged, cut, or irritated. Do not apply estradiol patches to the waistline where they may be rubbed off by tight clothing or ... off by sitting. Be sure that the skin in the area where you plan to apply ...

  20. Highly Compact Composite Antenna

    OpenAIRE

    Pigeon, Mélusine; Morlaas-Courties, Christophe; Aubert, Hervé; Souny, Bernard

    2009-01-01

    International audience; The highly compact antenna proposed in this communication consists of a judicious association of equivalent magnetic current source with equivalent electric current source. This composite antenna presents a directivity radiation pattern analogous to one of the microstrip ceramic antennas but can be used at low frequencies. The antenna measurements confirm the promising performances obtained from electromagnetic simulations.

  1. A Practical Guide to the Design and Construction of a Single Wire Beverage Antenna.

    Science.gov (United States)

    1980-09-01

    between Cyprus and the UK3. Radio and Navigation Department, RAE has evaluated a number of Beverage antennas at their Cobbett H-ill receiving station...rudimentary measarements have been made to characterise the Cobbett Hill Beverage antenna by using suspended standard radiators beneath a helicopter

  2. Design and Modeling of New UWB Metamaterial Planar Cavity Antennas with Shrinking of the Physical Size for Modern Transceivers

    Directory of Open Access Journals (Sweden)

    Mohammad Alibakhshi Kenari

    2013-01-01

    Full Text Available A variety of antennas have been engineered with MTMs and MTM-inspired constructs to improve their performance characteristics. This report describes the theory of MTMs and its utilization for antenna's techniques. The design and modeling of two MTM structures with ε-μ constitutive parameters for patch antennas are presented. The framework presents two novel ultrawideband (UWB shrinking patch antennas filled with composite right-/left-handed transmission line (CRLH-TL structures. The CRLH-TL is presented as a general TL possessing both left-handed (LH and right-handed (RH natures. The CRLH-TL structures enhance left-handed (LH characteristics which enable size reduction and large frequency bandwidth. The large frequency bandwidth and good radiation properties can be obtained by adjusting the dimensions of the patches and CRLH-TL structures. This contribution demonstrates the possibility of reducing the size of planar antennas by using LH-transmission lines. Two different types of radiators are investigated—a planar patch antenna composed of four O-formed unit cells and a planar patch antenna composed of six O-shaped unit cells. A CRLH-TL model is employed to design and compare these two approaches and their realization with a varying number of L-C loaded unit cells. Two representative antenna configurations have been selected and subsequently optimized with full-wave electromagnetic analysis. Return loss and radiation pattern simulations of these antennas prove the developed concept.

  3. Generic patch inference

    DEFF Research Database (Denmark)

    Andersen, Jesper; Lawall, Julia

    2010-01-01

    A key issue in maintaining Linux device drivers is the need to keep them up to date with respect to evolutions in Linux internal libraries. Currently, there is little tool support for performing and documenting such changes. In this paper we present a tool, spdiff, that identifies common changes...... made in a set of files and their updated versions, and extracts a generic patch performing those changes. Library developers can use our tool to extract a generic patch based on the result of manually updating a few typical driver files, and then apply this generic patch to other drivers. Driver...

  4. Transparent solar antenna of 28 GHz using transparent conductive oxides (TCO) thin film

    Science.gov (United States)

    Ali, N. I. Mohd; Misran, N.; Mansor, M. F.; Jamlos, M. F.

    2017-05-01

    This paper presents the analysis of 28GHz solar patch antenna using the variations of transparent conductive oxides (TCO) thin film as the radiating patch. Solar antenna is basically combining the function of antenna and solar cell into one device and helps to maximize the usage of surface area. The main problem of the existing solar antenna is the radiating patch which made of nontransparent material, such as copper, shadowing the solar cell and degrades the total solar efficiency. Hence, by using the transparent conductive oxides (TCO) thin film as the radiating patch, this problem can be tackled. The TCO thin film used is varied to ITO, FTO, AgHT-4, and AgHT-8 along with glass as substrate. The simulation of the antenna executed by using Computer Simulation Technology (CST) Microwave Studio software demonstrated at 28 GHz operating frequency for 5G band applications. The performance of the transparent antennas is compared with each other and also with the nontransparent patch antenna that using Rogers RT5880 as substrate, operating at the same resonance frequency and then, the material that gives the best performance is identified.

  5. Antenna-coupled arrays of voltage-biased superconducting bolometers

    Energy Technology Data Exchange (ETDEWEB)

    Myers, Michael J.; Lee, Adrian T.; Richards, P.L.; Schwan, D.; Skidmore, J.T.; Smith, A.D.; Spieler, H.; Yoon, Jongsoo

    2001-07-23

    We report on the development of antenna-coupled Voltage-biased Superconducting Bolometers (VSBs) which use Transition-edge Sensors (TES). Antenna coupling can greatly simplify the fabrication of large multi-frequency bolometer arrays compared to horn-coupled techniques. This simplification can make it practical to implement 1000+ element arrays that fill the focal plane of mm/sub-mm wave telescopes. We have designed a prototype device with a double-slot dipole antenna, integrated band-defining filters, and a membrane-suspended bolometer. A test chip has been constructed and will be tested shortly.

  6. A novel LTCC differentially Fed UWB antenna for the 60 GHz band

    NARCIS (Netherlands)

    Yang, B.; Yarovoy, A.G.; Valavan, A.S.E.; Buisman, K.; Shoykhetbrod, O.

    2011-01-01

    In this paper a novel differentially fed Ultra-Wide Band (UWB) antenna in low-temperature co-fired ceramics (LTCC) technology to be used in the 60 GHz band for integrated RF front-ends is presented. The antenna is based on the aperture stacked patch fed via H-shaped aperture to achieve more than 10

  7. Oxybutynin Transdermal Patch

    Science.gov (United States)

    ... soap and water. Do not use alcohol, nail polish remover, or other solvents. Apply a new patch ... else take your medication. Ask your pharmacist any questions you have about refilling your prescription.It is ...

  8. Lidocaine Transdermal Patch

    Science.gov (United States)

    Lidocaine patches are used to relieve the pain of post-herpetic neuralgia (PHN; the burning, stabbing pains, ... for months or years after a shingles infection). Lidocaine is in a class of medications called local ...

  9. Fentanyl Transdermal Patch

    Science.gov (United States)

    Fentanyl patches are used to relieve severe pain in people who are expected to need pain medication ... and who cannot be treated with other medications. Fentanyl is in a class of medications called opiate ( ...

  10. Reduced-volume antennas with integrated high-impedance electromagnetic surfaces.

    Energy Technology Data Exchange (ETDEWEB)

    Forman, Michael A.

    2006-11-01

    Several antennas with integrated high-impedance surfaces are presented. The high-impedance surface is implemented as a composite right/left-handed (CRLH) metamaterial fabricated from a periodic structure characterized by a substrate, filled with an array of vertical vias and capped by capacitive patches. Omnidirectional antennas placed in close proximity to the high-impedance surface radiate hemispherically with an increase in boresight far-field pattern gain of up to 10 dB and a front-to-back ratio as high as 13 dB at 2.45 GHz. Several TEM rectangular horn antennas are realized by replacing conductor walls with high-impedance surfaces. The TEM horn antennas are capable of operating below the TE{sub 1,0} cutoff frequency of a standard all-metal horn antenna, enabling a reduction in antenna volume. Above the cutoff frequency the TEM horn antennas function similarly to standard rectangular horn antennas.

  11. Compact U-Slotted Antenna for Broadband Radar Applications

    Directory of Open Access Journals (Sweden)

    S. Costanzo

    2013-01-01

    Full Text Available The original U-shaped patch antenna is properly modified in this work to provide a compact and broadband antenna configuration with reduced cross-polar effects, well suitable for modern radar applications. The proposed antenna layout is applied to design, realize, and test two different prototypes working at P-band and C-band, typically adopted for ground-penetrating radar. The experimental results successfully demonstrate a large operating bandwidth between 15% and 20%, a significant reduction of size (about half of the standard configuration, and a low cross-polarization level within the operating frequency range.

  12. Reconfigurable Front-end Antennas for Cognitive Radio Applications

    Science.gov (United States)

    2011-01-01

    and narrowband antenna is fabricated. The wideband antenna is a CPW fed printed hour-glass shaped monopole, which operates from 3 to 11 GHz. The...rotating the antenna patch by 1808, a different structure is being fed by the microstrip line. This rotation will produce different resonances , making the... resonance to the 4.8–5.7 GHz band. By illuminating the second switch (S2), using the same amount of pumped power, the band 3.2–4.3 GHz is covered. The

  13. Windows Security patch required

    CERN Multimedia

    2003-01-01

    This concerns Windows PCs (XP, 2000, NT) which are NOT centrally managed at CERN for security patches, e.g. home PCs, experiment PCs, portables, ... A security hole which can give full privileges on Windows systems needs to be URGENTLY patched. Details of the security hole and hotfix are at: http://cern.ch/it-div/news/hotfix-MS03-026.asp http://www.microsoft.com/technet/security/bulletin/MS03-026.asp

  14. Windows Security patch required

    CERN Multimedia

    3004-01-01

    This concerns Windows PCs (XP, 2000, NT) which are NOT centrally managed at CERN for security patches, e.g. home PCs, experiment PCs, portables,... A security hole which can give full privileges on Windows systems needs to be URGENTLY patched. Details of the security hole and hotfix are at: http://cern.ch/it-div/news/hotfix-MS03-026.asp http://www.microsoft.com/technet/security/bulletin/MS03-026.asp

  15. Windows Security patch required

    CERN Multimedia

    2003-01-01

    This concerns Windows PCs (XP, 2000, NT) which are NOT centrally managed at CERN for security patches, e.g. home PCs, experiment PCs, portables,... A security hole which can give full privileges on Windows systems needs to be URGENTLY patched. Details of the security hole and hotfix are at: http://cern.ch/it-div/news/hotfix-MS03-026.asp http://www.microsoft.com/technet/security/bulletin/MS03-026.asp

  16. Compact Dual Band Antenna Design for Ku / Ka Band Applications

    Directory of Open Access Journals (Sweden)

    A. Kandwal

    2017-10-01

    Full Text Available This communication proposes a compact 16 GHz / 30 GHz dual band antenna design for Ku / Ka band applications. The antenna consists of two layers with lower layer having the fed patch and the upper layer having non-periodic element array. The antenna has been designed to operate at two different frequencies with compact dimensions of (8mm x 8mm using Rogers RT 5880. The compact size of this proposed antenna also makes it suitable for integration with the microwave and millimeter wave circuits. The proposed antenna provides high radiation efficiency and a peak gain of about 8 dB at the resonant frequencies with reduced side lobe levels.

  17. A Small UWB Antenna with Dual Band-Notched Characteristics

    Directory of Open Access Journals (Sweden)

    J. Xu

    2012-01-01

    Full Text Available A small novel ultrawideband (UWB antenna with dual band-notched functions is proposed. The dual band rejection is achieved by etching two C-shaped slots on the radiation patch with limited area. A single band-notched antenna is firstly presented, and then an optimized dual band-notched antenna is presented and analyzed. The measured VSWR shows that the proposed antenna could operate from 3.05 to 10.7 GHz with VSWR less than 2, except two stopbands at 3.38 to 3.82 GHz and 5.3 to 5.8 GHz for filtering the WiMAX and WLAN signals. Radiation patterns are simulated by HFSS and verified by CST, and quasiomnidirectional radiation patterns in the H-plane could be observed. Moreover, the proposed antenna has a very compact size and could be easily integrated into portable UWB devices.

  18. A 1 GHz Oscillator-Type Active Antenna

    Science.gov (United States)

    Jordan, Jennifer L.; Scardelletti, Maximilian; Ponchak, George E.

    2008-01-01

    Wireless sensors are desired for monitoring aircraft engines, automotive engines, industrial machinery, and many other applications. The most important requirement of sensors is that they do not interfere with the environment that they are monitoring. Therefore, wireless sensors must be small, which demands a high level of integration. Sensors that modulate an oscillator active antenna have advantages of small size, high level of integration, and lower packaging cost. Several types of oscillator active antennas have been reported. Ip et al. demonstrated a CPW line fed patch antenna with a feedback loop [1]. No degradation in performance was noticed without a ground plane. A GaAs FET was used in an amplifier/oscillator-based active antenna [2]. An oscillator based on a Cree SiC transistor was designed and characterized in [3]. This paper reports the integration of the SiC Clapp oscillator to a slotline loop antenna.

  19. A Rectangular Planar Spiral Antenna for GIS Partial Discharge Detection

    Directory of Open Access Journals (Sweden)

    Xiaoxing Zhang

    2014-01-01

    Full Text Available A rectangular planar spiral antenna sensor was designed for detecting the partial discharge in gas insulation substations (GIS. It can expediently receive electromagnetic waves leaked from basin-type insulators and can effectively suppress low frequency electromagnetic interference from the surrounding environment. Certain effective techniques such as rectangular spiral structure, bow-tie loading, and back cavity structure optimization during the antenna design process can miniaturize antenna size and optimize voltage standing wave ratio (VSWR characteristics. Model calculation and experimental data measured in the laboratory show that the antenna possesses a good radiating performance and a multiband property when working in the ultrahigh frequency (UHF band. A comparative study between characteristics of the designed antenna and the existing quasi-TEM horn antenna was made. Based on the GIS defect simulation equipment in the laboratory, partial discharge signals were detected by the designed antenna, the available quasi-TEM horn antenna, and the microstrip patch antenna, and the measurement results were compared.

  20. Three Dimensional (3 D) Printed Sierpinski Patch Antenna

    Science.gov (United States)

    2017-10-25

    the expertise in this field is also rapidly expanding . The 4-year hiring trends in the field of additive manufacturing are shown in Figure 1. The...Testing of Acrylonitrile Butadiene Styrene (ABS), High Impact Polystyrene (HIPS) and Polylactic Acid (PLA) Plastics: A Comparative Study Between

  1. Cable suspended windmill

    Science.gov (United States)

    Farmer, Moses G. (Inventor)

    1990-01-01

    A windmill is disclosed which includes an airframe having an upwind end and a downwind end. The first rotor is rotatably connected to the airframe, and a generator is supported by the airframe and driven by the rotor. The airframe is supported vertically in an elevated disposition by poles which extend vertically upwardly from the ground and support cables which extend between the vertical poles. Suspension cables suspend the airframe from the support cable.

  2. Metamaterial-Backed Conformal Antennas for Space Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The high-permittivity substrate (er = 10.2) allows individual antenna patches to be made smaller and also mimics substrates (Si, SiC, GaAs, InP, GaN) used in MMIC...

  3. A Compact Multiband Notch UWB Antenna

    Directory of Open Access Journals (Sweden)

    K. Kumar

    2012-01-01

    Full Text Available A simple and a compact coplanar waveguide (CPW ultrawide band (UWB antenna is presented. Multiband stop function is achieved by two different types of band stop resonators. One is a tilted square spiral slot resonator of different size and length etched on the patch and the other is a coupled resonator etched on the ground plane. These resonators provide considerable increase in notch bandwidth at the stop bands. The proposed antenna has a total size of 18×20.3 mm2. The designed antenna achieves pass band performance at 1.8–2.1 GHz (15.38%, 3.0–3.2 GHz (6.45%, 4.4–4.7 GHz (6.59%, 6.3-6.4 GHz (1.57%, and 8–11.2 GHz (33.33% where VSWR <2 and four stop bands at 2.4–2.8 GHz (15.38%, 3.2–3.7 GHz (14.49%, 5.5–6 GHz (8.69%, and 6.5–7 GHz (7.40% where VSWR is equal to 10. The antenna has a peak gain of 3.8 dBi. The measured results show that the antenna achieves good impedance matching and consistent radiation patterns over an operating bandwidth.

  4. Wide-Angle-Scanning Reflectarray Antennas Actuated by MEMS

    Science.gov (United States)

    Fang, Houfei; Huang, John; Thomson, Mark W.

    2009-01-01

    An effort to develop large-aperture, wide-angle-scanning reflectarray antennas for microwave radar and communication systems is underway. In an antenna of this type as envisioned, scanning of the radiated or incident microwave beam would be effected through mechanical rotation of the passive (reflective) patch antenna elements, using microelectromechanical systems (MEMS) stepping rotary actuators typified by piezoelectric micromotors. It is anticipated that the cost, mass, and complexity of such an antenna would be less than, and the reliability greater than, those of an electronically scanned phased-array antenna of comparable beam-scanning capability and angular resolution. In the design and operation of a reflectarray, one seeks to position and orient an array of passive patch elements in a geometric pattern such that, through constructive interference of the reflections from them, they collectively act as an efficient single reflector of radio waves within a desired frequency band. Typically, the patches lie in a common plane and radiation is incident upon them from a feed horn.

  5. Biocide patch tests

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Veien, Niels

    1985-01-01

    Routine patch testing with a series of 6 industrial biocides containing methylene-bis-thiocyanate (Cytox 3522), benzisothiazolin-3-one (BIT), chlorocresol (Preventol CMK), 2-n-octyl-4-isothiazolin-3-one (Kathon 893), polyhydroxymethylene monobenzylether (Preventol D2) or 1,3,5-tris (hydroxy......-ethyl) hexahydrotriazine (Grotan BK) was carried out in 6 Danish out-patient clinics to evaluate guinea pig allergy test results with the same compounds. A total of 1652 consecutive patients with dermatitis were tested. The usefulness of this patch test battery was limited. There were a few positive reactions to Cytox...... of male patients and atopics, but significant differences in the frequencies of occupational cases, hand eczemas, and leg ulcers/stasis dermatitis, indicating possible variations in referral patterns, use of patch tests, and/or environmental factors....

  6. Large-Aperture Membrane Active Phased-Array Antennas

    Science.gov (United States)

    Karasik, Boris; McGrath, William; Leduc, Henry

    2009-01-01

    Large-aperture phased-array microwave antennas supported by membranes are being developed for use in spaceborne interferometric synthetic aperture radar systems. There may also be terrestrial uses for such antennas supported on stationary membranes, large balloons, and blimps. These antennas are expected to have areal mass densities of about 2 kg/sq m, satisfying a need for lightweight alternatives to conventional rigid phased-array antennas, which have typical areal mass densities between 8 and 15 kg/sq m. The differences in areal mass densities translate to substantial differences in total mass in contemplated applications involving aperture areas as large as 400 sq m. A membrane phased-array antenna includes patch antenna elements in a repeating pattern. All previously reported membrane antennas were passive antennas; this is the first active membrane antenna that includes transmitting/receiving (T/R) electronic circuits as integral parts. Other integral parts of the antenna include a network of radio-frequency (RF) feed lines (more specifically, a corporate feed network) and of bias and control lines, all in the form of flexible copper strip conductors on flexible polymeric membranes. Each unit cell of a prototype antenna (see Figure 1) contains a patch antenna element and a compact T/R module that is compatible with flexible membrane circuitry. There are two membrane layers separated by a 12.7-mm air gap. Each membrane layer is made from a commercially available flexible circuit material that, as supplied, comprises a 127-micron-thick polyimide dielectric layer clad on both sides with 17.5-micron-thick copper layers. The copper layers are patterned into RF, bias, and control conductors. The T/R module is located on the back side of the ground plane and is RF-coupled to the patch element via a slot. The T/R module is a hybrid multilayer module assembled and packaged independently and attached to the membrane array. At the time of reporting the information for

  7. The solar probe antenna

    Science.gov (United States)

    Imbriale, W. A.; Randolph, J. E.; Embuido, E.

    2004-01-01

    This paper details the design of the antenna intended for use on the Solar Probe Mission. The antenna consists of a carbon-carbon reflector jointly used as the antenna and thermal shield and helical feed using tungsten wire and ceramic matrix composite (CMC) materials for the back plate, coaxial cable waveguide. A complete prototype feed assembly was fabricated and tested.

  8. Image inpainting by patch propagation using patch sparsity.

    Science.gov (United States)

    Xu, Zongben; Sun, Jian

    2010-05-01

    This paper introduces a novel examplar-based inpainting algorithm through investigating the sparsity of natural image patches. Two novel concepts of sparsity at the patch level are proposed for modeling the patch priority and patch representation, which are two crucial steps for patch propagation in the examplar-based inpainting approach. First, patch structure sparsity is designed to measure the confidence of a patch located at the image structure (e.g., the edge or corner) by the sparseness of its nonzero similarities to the neighboring patches. The patch with larger structure sparsity will be assigned higher priority for further inpainting. Second, it is assumed that the patch to be filled can be represented by the sparse linear combination of candidate patches under the local patch consistency constraint in a framework of sparse representation. Compared with the traditional examplar-based inpainting approach, structure sparsity enables better discrimination of structure and texture, and the patch sparse representation forces the newly inpainted regions to be sharp and consistent with the surrounding textures. Experiments on synthetic and natural images show the advantages of the proposed approach.

  9. Height dependence of antenna factors of antennas for disturbance measurement

    Science.gov (United States)

    Tejima, Teruo; Harima, Katsushige; Koike, Kunimasa; Masuzawa, Hiroshi

    1995-06-01

    This paper investigates the height dependence of various antenna factors for tuned-dipole antennas, shortened-dipole antennas and the biconical antennas commonly used for electro-magnetic disturbance measurements from 30 MHz to 300 MHz. This height dependence is measured by the three-antenna method at an open-field-test site. Our results indicate tuned-dipole antenna strongly depend on antenna height, and biconical antenna depend on antenna height above 75 MHz. This study is based on the assumption that the antennas are properly calibrated.

  10. A Cylindrical Wideband Conformal Fractal Antenna for GPS Application

    Directory of Open Access Journals (Sweden)

    R. Sahoo

    2017-10-01

    Full Text Available In this paper, a novel wideband conformal fractal antenna is proposed for GPS application. The concepts of fractal and partial ground are used in conformal antenna design for miniaturization and bandwidth enhancement. It comprises of Minkowski fractal patch on a substrate of Rogers RT/duroid 5880 with permittivity 2.2 and thickness of 0.787mm with microstrip inset feed. The proposed conformal antenna has a patch dimension about 0.39λmm×0.39λmm, and partial ground plane size is 29mm×90mm.The proposed antenna is simulated, fabricated and measured for both planar and conformal geometry, with good agreement between measurements and simulations. The size of the fractal patch is reduced approximately by 32% as compared with conventional patch. It is observed that the conformal antenna exhibits a fractional bandwidth(for the definition of -10dB of 43.72% operating from 1.09 to 1.7GHz, which is useful for L1(1.56-1.58GHz, L2(1.21-1.23GHz, L3(1.37-1.39GHz, L4(1.36-1.38GHz, and L5(1.16-1.18 GHz in GPS and Galileo frequencies: E=1589.742MHz(4MHzbandwidth, E2=1561. 098MHz(4MHzbandwidth, E5a=1176.45MHz(=L5,E5b= 1207.14MHz, and E6=1278.75MHz(40MHz bandwidth. The radiation pattern exhibits an omnidirectional pattern, and gain of proposed antenna is 2.3dBi to 3.5dBi within operating frequency range.

  11. Ferrite LTCC-based antennas for tunable SoP applications

    KAUST Repository

    Shamim, Atif

    2011-07-01

    For the first time, ferrite low temperature co-fired ceramic (LTCC) tunable antennas are presented. These antennas are frequency tuned by a variable magnetostatic field produced in a winding that is completely embedded inside the ferrite LTCC substrate. Embedded windings have reduced the typically required magnetic bias field for antenna tuning by over 95%. The fact that large electromagnets are not required for tuning makes ferrite LTCC with embedded bias windings an ideal platform for advanced tunable system-on-package applications. Measurements of rectangular microstrip patch antennas on a ferrite LTCC substrate display a maximum tuning range of 610 MHz near 12 GHz. Two different bias windings and their effect on the antenna performance are discussed, as is the effect of antenna orientation with respect to the bias winding. The antenna radiation patterns are measured under biased and unbiased conditions, showing a stable co-polarized linear gain. © 2011-2012 IEEE.

  12. The analysis of reactively loaded microstrip antennas by finite difference time domain modelling

    Science.gov (United States)

    Hilton, G. S.; Beach, M. A.; Railton, C. J.

    1990-01-01

    In recent years, much interest has been shown in the use of printed circuit antennas in mobile satellite and communications terminals at microwave frequencies. Although such antennas have many advantages in weight and profile size over more conventional reflector/horn configurations, they do, however, suffer from an inherently narrow bandwidth. A way of optimizing the bandwidth of such antennas by an electronic tuning technique using a loaded probe mounted within the antenna structure is examined, and the resulting far-field radiation patterns are shown. Simulation results from a 2D finite difference time domain (FDTD) model for a rectangular microstrip antenna loaded with shorting pins are given and compared to results obtained with an actual antenna. It is hoped that this work will result in a design package for the analysis of microstrip patch antenna elements.

  13. Century Tide Nicotine Patch

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Century Tide Nicotine Patch, a hi-tech smoking control therapy, is designed in accordance with the scientific principle of nicotine replacement. The therapy is promoted by the World Health Organization. Meanwhile, it also integrates traditional Chinese medical therapy and adopts advanced TTS technology.

  14. Testosterone Transdermal Patch

    Science.gov (United States)

    ... growth, development, and functioning of the male sexual organs and typical male characteristics. Testosterone transdermal patches work ... Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat ...

  15. Long range ultra-high frequency (UHF) radio frequency identification (RFID) antenna design

    Science.gov (United States)

    Reynolds, Nathan D.

    There is an ever-increasing demand for radio frequency identification (RFID) tags that are passive, long range, and mountable on multiple surfaces. Currently, RFID technology is utilized in numerous applications such as supply chain management, access control, and public transportation. With the combination of sensory systems in recent years, the applications of RFID technology have been extended beyond tracking and identifying. This extension includes applications such as environmental monitoring and healthcare applications. The available sensory systems usually operate in the medium or high frequency bands and have a low read range. However, the range limitations of these systems are being overcome by the development of RFID sensors focused on utilizing tags in the ultra-high frequency (UHF) band. Generally, RFID tags have to be mounted to the object that is being identified. Often the objects requiring identification are metallic. The inherent properties of metallic objects have substantial effects on nearby electromagnetic radiation; therefore, the operation of the tag antenna is affected when mounted on a metallic surface. This outlines one of the most challenging problems for RFID systems today: the optimization of tag antenna performance in a complex environment. In this research, a novel UHF RFID tag antenna, which has a low profile, long range, and is mountable on metallic surfaces, is designed analytically and simulated using a 3-D electromagnetic simulator, ANSYS HFSS. A microstrip patch antenna is selected as the antenna structure, as patch antennas are low profile and suitable for mounting on metallic surfaces. Matching and theoretical models of the microstrip patch antenna are investigated. Once matching and theory of a microstrip patch antenna is thoroughly understood, a unique design technique using electromagnetic band gap (EBG) structures is explored. This research shows that the utilization of an EBG structure in the patch antenna design yields

  16. A Compact Wide-Band Hybrid Dielectric Resonator Antenna with Enhanced Gain and Low Cross-Polarization

    Directory of Open Access Journals (Sweden)

    Feibiao Dong

    2017-01-01

    Full Text Available By loading two printed patches to the dielectric resonator antenna (DRA, a compact wide-band hybrid dielectric resonator antenna with enhanced gain and low cross-polarization is presented. The proposed antenna utilizes a combination of a rectangular dielectric resonator and two printed patches. Due to the hybrid design, multiple resonances were obtained. By adding two air layers between the dielectric resonator and the printed patches, the bandwidth has been significantly improved. Compared to the traditional hybrid dielectric resonator antenna, the proposed antenna can achieve wide bandwidth, high gain, low cross-polarization, and even small size simultaneously. The prototype of the proposed antenna has been fabricated and tested. The measured −10 dB return loss bandwidth is 25.6% (1.7–2.2 GHz. The measured antenna gains are about 6.3 and 8.2 dBi in the operating frequency band. Low cross-polarization levels of less than −28.5 dB and −43 dB in the E-plane and H-plane are achieved. Moreover, the overall dimensions of the antenna are only 67 × 67 × 34 (mm3. The proposed antenna is especially attractive for small base antenna applications.

  17. Omnidirectional Antenna with Multi-Resonance Performance for Microwave Imaging Systems

    Directory of Open Access Journals (Sweden)

    N. Ojaroudi

    2013-11-01

    Full Text Available In this paper, a novel ultra-wideband printed monopole antenna (PMA for microwave imaging systems is presented. The proposed antenna provides a wide usable fractional bandwidth of more than 160% (2.12-17.87 GHz. The antenna has an ordinary square radiating patch, therefore displays a good omni-directional radiation pattern even at higher frequencies and also its radiation efficiency is greater than 82% across the entire radiating band. The designed antenna has a small size of 12×18 mm2.

  18. Con-Patch: When a Patch Meets its Context

    OpenAIRE

    Romano, Yaniv; Elad, Michael

    2016-01-01

    Measuring the similarity between patches in images is a fundamental building block in various tasks. Naturally, the patch-size has a major impact on the matching quality, and on the consequent application performance. Under the assumption that our patch database is sufficiently sampled, using large patches (e.g. 21-by-21) should be preferred over small ones (e.g. 7-by-7). However, this "dense-sampling" assumption is rarely true; in most cases large patches cannot find relevant nearby examples...

  19. Dispersive suspended microextraction.

    Science.gov (United States)

    Yang, Zhong-Hua; Liu, Yu; Lu, Yue-Le; Wu, Tong; Zhou, Zhi-Qiang; Liu, Dong-Hui

    2011-11-14

    A novel sample pre-treatment technique termed dispersive suspended microextraction (DSME) coupled with gas chromatography-flame photometric detection (GC-FPD) has been developed for the determination of eight organophosphorus pesticides (ethoprophos, malathion, chlorpyrifos, isocarbophos, methidathion, fenamiphos, profenofos, triazophos) in aqueous samples. In this method, both extraction and two phases' separation process were performed by the assistance of magnetic stirring. After separating the two phases, 1 μL of the suspended phase was injected into GC for further instrument analysis. Varieties of experiment factors which could affect the experiment results were optimized and the following were selected: 12.0 μL p-xylene was selected as extraction solvent, extraction speed was 1200 rpm, extraction time was 30 s, the restoration speed was 800 rpm, the restoration time was 8 min, and no salt was added. Under the optimum conditions, limits of detections (LODs) varied between 0.01 and 0.05 μg L(-1). The relative standard deviation (RSDs, n=6) ranged from 4.6% to 12.1%. The linearity was obtained by five points in the concentration range of 0.1-100.0 μg L(-1). Correlation coefficients (r) varied from 0.9964 to 0.9995. The enrichment factors (EFs) were between 206 and 243. In the final experiment, the developed method has been successfully applied to the determination of organophosphorus pesticides in wine and tap water samples and the obtained recoveries were between 83.8% and 101.3%. Compared with other pre-treatment methods, DSME has its own features and could achieve satisfied results for the analysis of trace components in complicated matrices. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Spin Glass Patch Planting

    Science.gov (United States)

    Wang, Wenlong; Mandra, Salvatore; Katzgraber, Helmut G.

    2016-01-01

    In this paper, we propose a patch planting method for creating arbitrarily large spin glass instances with known ground states. The scaling of the computational complexity of these instances with various block numbers and sizes is investigated and compared with random instances using population annealing Monte Carlo and the quantum annealing DW2X machine. The method can be useful for benchmarking tests for future generation quantum annealing machines, classical and quantum mechanical optimization algorithms.

  1. Patch test with preservatives

    Directory of Open Access Journals (Sweden)

    Kar Sumit

    1992-01-01

    Full Text Available Of the 705 patients patch tested between March 88 to March 91, 317 were tested for sensitivity to preservatives with antigens obtained from Chemo technique AB, Sweden. Paraben was the commonest sensitizer (22.4% followed by Groton B K (8.1% and Triclosan (6.5%. We stress the need to consider these allergens as source of dermatitis and advocate complete labelling of topical preparations marketed.

  2. Dielectrically Loaded Biconical Antennas

    Science.gov (United States)

    Nusseibeh, Fouad Ahmed

    1995-01-01

    Biconical antennas are of great interest to those who deal with broadband applications including the transmission/reception of pulses. In particular, wide-angle conical antennas are an attractive choice in many applications including Electronic Support Measures (ESM) and the measurements of transient surface currents and charge densities on aircraft. Dielectric loading in the interior region of a conical antenna can be used to reduce the size of the antenna especially at low frequencies and/or for structural strength. Therefore, having an analytical solution for the input impedance and the frequency response is very helpful in optimizing the design and understanding the behavior of the antenna. From the quasi-analytical solution for the input impedance and the electric field of a wide-angle conical antenna, it can be seen that the dielectric loading in the antenna region improves the input impedance at low frequencies, but increases the number of resonance points and the magnitude of these peaks. When an inhomogeneous dielectric load is used, the magnitude of the resonance peaks is decreased (depending on the way the load is distributed), improving the input impedance of the antenna significantly. Introducing a dielectric load in the interior region of an electrically short receiving cone makes the antenna behave as an electrically longer antenna. However, this is not true for the case for electrical1y long antennas. For the case of pulse transmission, the dielectric load affects only the amplitude. Of course, if the dielectric fills the whole space, both transmitting and receiving antennas behave as electrically longer antennas.

  3. Ferrite LTCC based phased array antennas

    KAUST Repository

    Ghaffar, Farhan A.

    2016-11-02

    Two phased array antennas realized in multilayer ferrite LTCC technology are presented in this paper. The use of embedded bias windings in these designs allows the negation of external magnets which are conventionally employed with bulk ferrite medium. This reduces the required magnetostatic field strength by 90% as compared to the traditional designs. The phase shifters are implemented using the SIW technology. One of the designs is operated in the half mode waveguide topology while the other design is based on standard full mode waveguide operation. The two phase shifter designs are integrated with two element patch antenna array and slotted SIW array respectively. The array designs demonstrate a beam steering of 30° and ±19° respectively for a current excitation of 200 mA. The designs, due to their small factor can be easily integrated in modern communication systems which is not possible in the case of bulk ferrite based designs.

  4. Cirlularly Polarized Proximity- Fed Microstrip Array Antenna for LAPAN TUBSAT Micro Satellite System

    Directory of Open Access Journals (Sweden)

    Endra Wijaya

    2013-11-01

    Full Text Available The design microstrip of array antenna circular polarization characteristic developed for support LAPAN TUBSAT micro satellite system. The antenna on the micro satellite systems transmit data to ground stations operating at S band frequencies.The antenna is designed for impedance matching at frequencies of 2:25 GHz.The four elements of the square patch antenna array composed using linear methods, where the design of the transmission lines used by federal corporate structure model network consisting of three elements of the quarter wave transformer of a power divider. The feeding techniques for antenna designed using proximity coupling method, which for the type of substrate material used is similar. Circularly polarized antenna characteristics are influenced by the truncated corner pieces on the patch. To design the overall antenna used simulated method of moments in microwave office software applications. The results of measurements and simulations obtained antenna parameters, such as: bandwidth of return loss under 10 dB is 200 MHz (shifted 35%, bandwidth of axial ratio under 3dB is 1.7% and maximum gain directivity is 9 dB. Overall results obtained antenna parameters to meet the specifications of LAPAN TUBSAT micro satellite system.

  5. A Multiband Monopole Antenna with the Inverted-Trapezoidal CPW Feeding

    Directory of Open Access Journals (Sweden)

    Quanqi Zhang

    2014-01-01

    Full Text Available A multi-band monopole antenna with the improved inverted-trapezoidal coplanar waveguide (CPW feeding is presented. The antenna has a simple planar structure, and occupies an area of 15 mm × 50 mm. The proposed antenna consists of an improved inverted-trapezoidal CPW-fed patch, and a series of monopole strips with different length. This monopole antenna utilizes the advantages of the CPW feeding to simplify the structure of the antenna into a single metallic level and achieve high antenna gain. The improved inverted-trapezoidal CPW-fed patch and a meander shorting strip lead to a better impedance matching result and multi-band operation. The experimental results of the proposed antenna are shown and discussed. The antenna generates two wide bands centered at about 900 and 2200 MHz to cover the GSM850/GSM900/DCS/PCS/UMTS/LTE2300/2500 bands and the 2.4 GHz WLAN operation. Meanwhile the antenna covers the 4 G bands of China Telecom (2370–2390 MHz/2635–2655 MHz, China Unicom (2300–2320 MHz/2555–2575 MHz and China Mobile (1880–1900 MHz/2320–2370 MHz/2575–2635 MHz, too.

  6. Unidirectional Magneto-Electric Dipole Antenna for Base Station: A Review

    Science.gov (United States)

    Idayachandran, Govindanarayanan; Nakkeeran, Rangaswamy

    2018-01-01

    Unidirectional base station antenna design using Magneto-Electric Dipole (MED) has created enormous interest among the researchers due to its excellent radiation characteristics like low back radiation, symmetrical radiation at E-plane and H-plane compared to conventional patch antenna. Generally, dual polarized antennas are used to increase channel capacity and reliability of the communication systems. In order to serve the evolving mobile communication standards like long term evolution LTE and beyond, unidirectional dual polarized MED antenna are required to have broad impedance bandwidth, broad half power beamwidth, high port isolation, low cross polarization level, high front to back ratio and high gain. In this paper, the critical electrical requirements of the base station antenna and frequently used frequency bands for modern mobile communication have been presented. It is followed by brief review on broadband patch antenna and discussion on complementary antenna concepts. Finally, the performance of linearly polarized and dual polarized magneto-electric dipole antennas along with their feeding techniques are discussed and summarized. Also, design and modeling of developed MED antenna is presented.

  7. Improving microwave antenna gain and bandwidth with phase compensation metasurface

    Directory of Open Access Journals (Sweden)

    Ke Chen

    2015-06-01

    Full Text Available Metasurface, as a planar version of artificial metamaterial, provide an effective way to manipulate electromagnetic wave propagation. Here, we present a transparent metasurface for compensating the out-of-phase radiation from a microstrip patch antenna to improve its radiation gain and bandwidth. Based on the equivalence principle of Huygens’ surface, we propose metasurface composed of both inductive and capacitive resonant elements which could produce high transmission with variable phase characteristics. Such metasurface mounted on a patch antenna can transform the spherical-like phase profile generated from the patch into an in-phase planar one. A prototype antenna has been fabricated and validated the squeezed radiation pattern with suppressed sidelobes as well as enhanced impedance bandwidth due to strong near-field coupling. As operating at around 5.7 GHz, the proposed antenna may have potential application in wireless communication systems especially for point-to-point data transmission. It is believed that the design methodology could also be scaled to other frequency bands such as millimeter or terahertz wave.

  8. Broadband Monopole Antenna

    Science.gov (United States)

    2017-09-14

    whose dominant axis is aligned with the z direction, the axis of the antenna inside. The material is indicated as having multiple resonances with at...least one resonance above that of the uncoated monopole. In this antenna, the diameter of the engineered material cylinder is much smaller than the... ground plane Attorney Docket No. 300161 3 of 13 that includes a monopole extending perpendicularly from the ground plane. The antenna feed is

  9. Highly decoupled cosited antennas

    Science.gov (United States)

    Campbell, Donn V.; Dubowicz, Palemon W.; Hoverter, Robert T.

    1986-08-01

    Two cosited omnidirectional biconical antennas are respectively tilted plus and minus 45 degrees (+ or - 45 deg.) with respect to the vertical and, therefore, are perpendicular (90 deg.) with respect to each other to effect polarization mismatch and near field decoupling. In combination with the described antennae orientation, high impedance cable chokes are added in series with the coaxial cable antennae feed lines to suppress induced parasitic RF currents.

  10. A Compact Annular Ring Microstrip Antenna for WSN Applications

    Directory of Open Access Journals (Sweden)

    Daihua Wang

    2012-06-01

    Full Text Available A compact annular ring microstrip antenna was proposed for a wireless sensor network (WSN application in the 2.4 GHz band. In this paper the major considerations of the conformal antenna design were the compact size and the impact on antenna’s performance of a steel installation base. By using a chip resistor of large resistance (120 Ω the antenna size was reduced to 38% of that a conventional annular ring patch antenna. With the addition of the steel installation base the resonant frequency of the antenna increases about 4.2% and the bandwidth reduces from 17.5% to 11.7% by adjusting the load resistance simultaneously. Several key parameters were discussed and optimized, and the antenna was fabricated and its performance measured. The antenna is well matched at 2.4 GHz with 34.2 dB return loss and –2.5 dBi peak gain. Meanwhile, it exhibits excellent radiation patterns with very low cross-polarization levels.

  11. Circular Microstrip Antenna with Fractal Slots for Multiband Applications

    Science.gov (United States)

    Singh, Sivia Jagtar; Singh, Gurpreet; Bharti, Gurpreet

    2017-10-01

    In this paper, a multiband, fractal, slotted, Circular Microstrip Patch Antenna for GSM, WiMAX, C and X bands (satellite communication applications) is presented. A cantor set theory is used to make fractal slots for obtaining the desired multiband. The projected antenna is simulated using Ansys HFSS v13.0 software. Simulation test of this antenna has been carried out for a frequency range of 1 GHz-10 GHz and a peak gain of 9.19 dB at a resonance frequency of 1.9 GHz is obtained. The antenna also resonates at 3.7 GHz, 6.06 GHz and 7.9 GHz with gains of 3.04 dB, 5.19 dB and 5.39 dB respectively. Parameters like voltage standing wave ratio, return loss, and gain are used to compare the results of the projected antenna with conventional CMPA's of same dimensions with full and defective grounds. The projected antenna is fabricated on a glass epoxy material and is tested using Vector Network Analyzer. The performance parameters of the antenna are found to in good agreement with each both using simulated and measured data.

  12. Compact Microstrip Antenna with Pattern-Reconfigurable Characteristic

    Directory of Open Access Journals (Sweden)

    W. D. Ma

    2017-09-01

    Full Text Available In this paper, a compact microstrip antenna with radiation pattern reconfigurable characteristic employing MEMS switches is proposed and investigated. This novel antenna mainly includes four parts: a circular-shaped patch, six MEMS switches, six fan-shaped coupling cells and six fan-shaped radiation cells. Through controlling the states of MEMS switches, radiation pattern selectivity of the proposed antenna can be achieved. When switching operation states of the antenna from state 1 to state 12 sequentially, the main radiation beam direction in azimuth planes could rotate 30˚ from 0˚ to 330˚ with each switch. Meanwhile, the radiation beam directions in elevation plane and the operation frequencies of proposed antenna for different operation states are stable at about 35˚ and 4GHz, respectively. With the consideration of MEMS switches actual size, the antenna structure and dimensions were optimized and adjusted. The simulated and measured results were analyzed and compared, indicating this compact antenna can be widely used for multifunctional applications and modern wireless communication systems.

  13. Inverted S-shaped compact antenna for X-band applications.

    Science.gov (United States)

    Samsuzzaman, M; Islam, M T

    2014-01-01

    A novel probe-fed compact inverted S-shaped multifrequency patch antenna is designed. By employing two rectangular slots that change the conventional rectangular patch into an inverted S-shaped patch, the antenna is able to operate in triple frequency in the X-band. The performance criteria of the proposed design have been experimentally verified by fabricating a printed prototype. The measured results show that the -10 dB impedance bandwidth of the proposed antenna at lower band is 5.02% (8.69-9.14 GHz), at middle band is 9.13% (10.47-11.48 GHz), and at upper band is 3.79% (11.53-11.98 GHz). Two elliptical slots are introduced in the ground plane to increase the peak gain. The antenna is excited by a simple probe feeding mechanism. The overall antenna dimension is  0.52λ × 0.60λ × 0.046λ at a lower resonance frequency of 9.08 GHz. The antenna configuration and parametric investigation are conducted with the help of the high frequency structural simulator, and a good agreement is achieved between the simulated and measured data. The stable gain, omnidirectional radiation pattern, and consistent radiation efficiency in the achieved operating band make the proposed antenna a suitable candidate for X-band applications.

  14. Inverted S-Shaped Compact Antenna for X-Band Applications

    Directory of Open Access Journals (Sweden)

    M. Samsuzzaman

    2014-01-01

    Full Text Available A novel probe-fed compact inverted S-shaped multifrequency patch antenna is designed. By employing two rectangular slots that change the conventional rectangular patch into an inverted S-shaped patch, the antenna is able to operate in triple frequency in the X-band. The performance criteria of the proposed design have been experimentally verified by fabricating a printed prototype. The measured results show that the −10 dB impedance bandwidth of the proposed antenna at lower band is 5.02% (8.69–9.14 GHz, at middle band is 9.13% (10.47–11.48 GHz, and at upper band is 3.79% (11.53–11.98 GHz. Two elliptical slots are introduced in the ground plane to increase the peak gain. The antenna is excited by a simple probe feeding mechanism. The overall antenna dimension is  0.52λ×0.60λ×0.046λ at a lower resonance frequency of 9.08 GHz. The antenna configuration and parametric investigation are conducted with the help of the high frequency structural simulator, and a good agreement is achieved between the simulated and measured data. The stable gain, omnidirectional radiation pattern, and consistent radiation efficiency in the achieved operating band make the proposed antenna a suitable candidate for X-band applications.

  15. Compact Antenna Range

    Data.gov (United States)

    Federal Laboratory Consortium — Facility consists of a folded compact antenna range including a computer controlled three axis position table, parabolic reflector and RF sources for the measurement...

  16. Tunable Handset Antenna

    DEFF Research Database (Denmark)

    Barrio, Samantha Caporal Del; Foroozanfard, Ehsan; Morris, Art

    2017-01-01

    With the future LTE auction for TV white spaces at 600 MHz, there is a strong need for efficient handset antennas operating at very low frequencies. This paper shows a tunable antenna covering the LTE bands from 600 MHz to 2.6 GHz. The antenna uses state-of-the-art MEMS tunable capacitors in order...... to reconfigure its operating frequency. In this work, the design mitigates the tuning loss with a tunable extended ground plane. The resulting dual-resonant antenna exhibits a peak total efficiency of -3.9 dB at 600 MHz....

  17. Tunable Handset Antenna

    DEFF Research Database (Denmark)

    Barrio, Samantha Caporal Del; Foroozanfard, Ehsan; Morris, Art

    2017-01-01

    With the future LTE auction for TV white spaces at 600 MHz, there is a strong need for efficient handset antennas operating at very low frequencies. This paper shows a tunable antenna covering the LTE bands from 600 MHz to 2.6 GHz. The antenna uses state-of-the-art MEMS tunable capacitors in orde...... to reconfigure its operating frequency. In this work, the design mitigates the tuning loss with a tunable extended ground plane. The resulting dual-resonant antenna exhibits a peak total efficiency of -3.9 dB at 600 MHz....

  18. Wide sector coverage antennas

    Science.gov (United States)

    Yaw, D. F.

    1984-09-01

    The general design and performance characteristics of transmit and receive antennas that are currently used in electronic warfare systems are reviewed. Among transmit antennas, three-to-one bandwidth, asymmetric-beam, and circularly polarized horns are discussed, as are extremely broadband monopoles and spiral antennas. In a discussion of receive antennas, attention is given to flat and conical spirals, including cavity-backed flat spirals operating over the 2.5-18 GHz range; log periodic dipoles; and biconical horns. Finally, the design configurations and performance of interferometer direction-finding systems are briefly discussed.

  19. MSU Antenna Pattern Data

    Science.gov (United States)

    Mo, Tsan; Kleespies, Thomas J.; Green, J. Philip

    2000-01-01

    The Microwave Sounding Unit (MSU) antenna pattern data for nine MSU Flight Models (FMs) have been successfully rescued from 22-year old 7-track and 9-track magnetic tapes and cartridges. These antenna pattern data were unpacked into user-friendly ASCII format, and are potentially useful for making antenna pattern corrections to MSU antenna temperatures in retrieving the true brightness temperatures. We also properly interpreted the contents of the data and show how to convert the measured antenna signal amplitude in volts into relative antenna power in dB with proper normalization. It is found that the data are of high quality with a 60-dB drop in the co-polarized antenna patterns from the central peak value to its side-lobe regions at scan angles beyond 30 deg. The unpacked antenna pattern data produced in this study provide a useful database for data users to correct the antenna side-lobe contribution to MSU measurements. All of the data are available to the scientific community on a single CD-ROM.

  20. Theoretical study of two-element array of equilateral triangular patch ...

    Indian Academy of Sciences (India)

    The radiation characteristics of a two-element array of equilateral triangular patch microstrip antenna on a ferrite substrate are studied theoretically by considering the presence of bias magnetic field in the direction of propagation of electromagnetic waves. It is found that the natural modes of propagation in the direction of ...

  1. PARAMETRIC ANALYSIS OF A MINIATURIZED INVERTED II SHAPED ANTENNA FOR WIRELESS SENSOR NETWORK APPLICATIONS

    Directory of Open Access Journals (Sweden)

    M. Shanmugapriya

    2015-06-01

    Full Text Available A compact and simple design of a CPW-fed planar antenna for wireless sensor network antenna application with a better size reduction is presented. The proposed antenna consists of an inverted ? shaped metal patch on a printed circuit board fed by a 50-O coplanar waveguide (CPW. The parametric analysis of length and width are made. The designed antenna’s physical dimensions are 32 mm (length x 26 mm (width x 1.6 mm (height. The antenna structure has been modeled and fabricated and its performance has been evaluated using a method of moment based electromagnetic simulator, IE3D .The return loss of -22.5 dB and VSWR of 1.34 dB are noted. The radiation pattern of the antenna proves that it radiates in all direction. The antenna is fabricated and tested and the measured results go in good agreement with simulated one.

  2. A Broadband Left-Handed Metamaterial Microstrip Antenna with Double-Fractal Layers

    Directory of Open Access Journals (Sweden)

    Roman Kubacki

    2017-01-01

    Full Text Available This paper proposes a microstrip patch antenna based on the left-handed metamaterial concept, using planar periodic geometry, which results in improved characteristics. This periodic geometry is derived from fractal shapes, which have been widely used in antenna engineering. The metamaterial property was obtained as a result of the double-fractal structure on both the upper and the bottom sides of the antenna. The final structure has been optimized to enhance bandwidth, gain, and radiation characteristics of the microstrip antenna. This combination significantly improved antenna performance; our design could support an ultrawide bandwidth ranging from 4.1 to 19.4 GHz, demonstrating higher gain with an average value of 6 dBi over the frequency range and a peak of 10.9 dBi and a radiation capability directed in the horizontal plane of the antenna.

  3. Circularly Polarized Aperture Coupled Microstrip Antenna with Resonant Slots and a Screen

    Directory of Open Access Journals (Sweden)

    G. S. Kirov

    2010-04-01

    Full Text Available A broadband circularly polarized (CP Aperture Coupled Microstrip Antenna (ACMSA is described herein. In order to decrease the back radiation of the antenna due to resonant coupling slots (a cross-slot in the ground plane, a three-layer structure with a screen is proposed. As a result, the back radiation of the antenna is reduced by more than 12 dB and its gain is increased by about 1.3 dB compared to the conventional two-layer ACMSA with nonresonant coupling slots. The antenna is designed to operate within the Ku-band. Keeping its simple and compact construction and high mechanical characteristics it can be used as an element of CP microstrip antenna arrays with various applications in the contemporary communication systems. A comparison with two similar CP antennas with resonant slots, a two-layer ACMSA and a three-layer ACMSA with a patch reflector is accomplished.

  4. Investigation of graphene based miniaturized terahertz antenna for novel substrate materials

    Directory of Open Access Journals (Sweden)

    Rajni Bala

    2016-03-01

    Full Text Available The selection of appropriate substrate material acts as a performance regulator for miniaturized graphene patch antenna. The substrate material not only controls the transport properties of graphene but also influences the resonant properties of the graphene patch antenna. The edge fed microstrip line graphene based rectangular patch antenna is designed here for operating in the frequency range 2.67–2.92 THz for wireless applications. The performance is investigated for silicon nitride, aluminum oxide, boron nitride, silica and quartz substrate materials on the basis of return loss, voltage standing wave ratio (VSWR, absorption cross section, bandwidth and radiation efficiency. The comparison of results shows that silicon nitride exhibits overall excellent performance by the virtue of having higher bandwidth and radiation efficiency as compared to other chosen substrate materials.

  5. Substrate integrated antennas and arrays

    CERN Document Server

    Cheng, Yu Jian

    2015-01-01

    Substrate Integrated Antennas and Arrays provides a single source for cutting-edge information on substrate integrated circuits (SICs), substrate integrated waveguide (SIW) feeding networks, SIW slot array antennas, SIC traveling-wave antennas, SIW feeding antennas, SIW monopulse antennas, and SIW multibeam antennas. Inspired by the author's extensive research, this comprehensive book:Describes a revolutionary SIC-based antenna technique with the potential to replace existing antenna technologiesExamines theoretical and experimental results connected to electrical and mechanical performanceExp

  6. Nimbus-7 SMMR Antenna Temperatures

    Data.gov (United States)

    National Aeronautics and Space Administration — The SMMR Antenna Temperatures (Nimbus-7) data set consists of antenna temperatures from passive microwave radiometers aboard NOAA's Nimbus-7 satellite. The...

  7. Design and Analysis of a Silicon-Based Pattern Reconfigurable Antenna Employing an Active Element Pattern Method

    Directory of Open Access Journals (Sweden)

    Ke Han

    2017-01-01

    Full Text Available In this paper, a silicon-based radio frequency micro-electromechanical systems (RF MEMS pattern reconfigurable antenna for a Ka-band application was designed, analyzed, fabricated, and measured. The proposed antenna can steer the beam among three radiating patterns (with main lobe directions of −20°, 0°, and +20° approximately at 35 GHz by switching RF MEMS operating modes. The antenna has a low profile with a small size of 3.7 mm × 4.4 mm × 0.4 mm, and consists of one driven patch, four parasitic patches, two assistant patches, and two RF MEMS switches. The active element pattern method integrated with signal flow diagram was employed to analyze the performances of the proposed antenna. Comparing the measured results with analytical and simulated ones, good agreements are obtained.

  8. Annular Planar Monopole Antennas

    OpenAIRE

    Chen, Z. N.; Ammann, Max; Chia, W.Y. W.; See, T. S.P.

    2002-01-01

    A type of annular planar monopole antenna is presented. The impedance and radiation characteristics of the monopole with different holes and feed gaps are experimentally examined. The measured results demonstrate that the proposed antenna is capable of providing significantly broad impedance bandwidth with acceptable radiation performance.

  9. MEMS Tunable Antennas

    DEFF Research Database (Denmark)

    Barrio, Samantha Caporal Del; Morris, Art; Pedersen, Gert Frølund

    2014-01-01

    Addressing low frequency bands is challenging on small platforms. Tunability is a promising solution to cover the bandwidth required for 4G mobile communication. The work presents two designs and shows that for comparable efficiency and bandwidth, the tunable antenna occupies half the volume...... required by the wide-band antenna....

  10. Printed Triband Terminal Antenna

    OpenAIRE

    John, Matthias; Ammann, Max; Farrell, R.

    2005-01-01

    This paper presents a printed triple-band multibranch monopole for use in modern wireless systems. The antenna is designed to operate in three bands which cover virtually all wireless channels. Parameters of the antenna geometry are varied and the effects of these variations on the impedance bandwidth are shown.

  11. Handbook of antenna technologies

    CERN Document Server

    Liu, Duixian; Nakano, Hisamatsu; Qing, Xianming; Zwick, Thomas

    2016-01-01

    The Handbook of Antenna Technologies aims to present the rapid development of antenna technologies, particularly in the past two decades, and also showcasing the newly developed technologies and the latest applications. The handbook will provide readers with the comprehensive updated reference information covering theory, modeling and optimization methods, design and measurement, new electromagnetic materials, and applications of antennas. The handbook will widely cover not only all key antenna design issues but also fundamentals, issues related to antennas (transmission, propagation, feeding structure, materials, fabrication, measurement, system, and unique design challenges in specific applications). This handbook will benefit the readers as a full and quick technical reference with a high-level historic review of technology, detailed technical descriptions and the latest practical applications.

  12. A CPW-Fed Quasi-PIFA Antenna Using Quasi-Lumped Resonators for Mobile Phones

    Directory of Open Access Journals (Sweden)

    Majid Rafiee

    2015-01-01

    Full Text Available A novel single CPW-fed Quasi-Planar Inverted-F Antenna (PIFA using quasi-lumped elements is developed for mobile communication handheld terminals operating at 2.6 GHz. The antenna is composed of an inductor covered by a set of interdigital and parasitic capacitors. The proposed antenna achieves a measured bandwidth of 11% for return loss with the antenna gain of about 4 dBi. The antenna is designed in single layer (zero height which is appropriate to be used in thin devices where a small room is considered for the antenna. The proposed antenna is suitable for use in Long Term Evolution band 7. The operating frequency of introduced antenna depends on the number of interdigital fingers and inductor length rather than the total resonator patch only, so that the operating frequency can be altered while the total patch size remains unchanged. The calculated operating frequency is confirmed by simulation and measurement. Also the dipole-like simulated radiation pattern is confirmed by measurement.

  13. Radiation and scattering from cylindrically conformal printed antennas. Ph.D. Thesis Final Report

    Science.gov (United States)

    Kempel, Leo C.; Volakis, John L.

    1994-01-01

    Microstrip patch antennas offer considerable advantages in terms of weight, aerodynamic drag, cost, flexibility, and observables over more conventional protruding antennas. These flat patch antennas were first proposed over thirty years ago by Deschamps in the United States and Gutton and Baisinot in France. Such antennas have been analyzed and developed for planar as well as curved platforms. However, the methods used in these designs employ gross approximations, suffer from extreme computational burden, or require expensive physical experiments. The goal of this thesis is to develop accurate and efficient numerical modeling techniques which represent actual antenna structures mounted on curved surfaces with a high degree of fidelity. In this thesis, the finite element method is extended to cavity-backed conformal antenna arrays embedded in a circular, metallic, infinite cylinder. Both the boundary integral and absorbing boundary mesh closure conditions will be used for terminating the mesh. These two approaches will be contrasted and used to study the scattering and radiation behavior of several useful antenna configurations. An important feature of this study will be to examine the effect of curvature and cavity size on the scattering and radiation properties of wraparound conformal antenna arrays.

  14. A micromachined freestanding terahertz absorber with an array of metallic patches

    Directory of Open Access Journals (Sweden)

    Hamdi Torun

    2016-03-01

    Full Text Available An array of square metallic patches on a thin suspended dielectric layer is introduced as an effective terahertz absorber. The suspended structure is placed on a metalized substrate and the device exhibits metamaterial behavior at specific frequencies determined by the size of the patches. It is feasible to place patches with different sizes in an array formation for a broadband absorber. In array configuration, individual elements induce distinct resonances yielding narrow band absorption regions. Design of the absorber is described using electromagnetic simulations. The absorber structure was fabricated on a silicon wafer using standard microfabrication techniques. The characteristics of the absorber were measured using a terahertz time domain spectroscope. The measured data match well the simulations indicating strong absorption peaks in a band of 0.5-2 THz.

  15. Liquid crystal polymer substrate based wideband tapered step antenna

    Directory of Open Access Journals (Sweden)

    Boddapati Taraka Phani MADHAV

    2015-05-01

    Full Text Available Performance study of wideband tapered step antenna on liquid crystal polymer substrate material is presented. Bandwidth enhancement is achieved by adding step serrated ground on the front side of the model along with the radiating patch. The radiating patch seems to be the intersection of two half circles connected back to back. The lower half circle radius is more than upper half circle radius. Wideband tapered step antenna is designed on the liquid crystal polymer substrate (Ultralam 3850, εr = 2.9 with dimensions of 20×20×0.5 mm. Coplanar waveguide feeding is used in this model with feed line width of 2.6 mm and gap between feed line to ground plane of 0.5 mm.

  16. A Hybrid Optimization Algorithm for Low RCS Antenna Design

    Directory of Open Access Journals (Sweden)

    W. Shao

    2012-12-01

    Full Text Available In this article, a simple and efficient method is presented to design low radar cross section (RCS patch antennas. This method consists of a hybrid optimization algorithm, which combines a genetic algorithm (GA with tabu search algorithm (TSA, and electromagnetic field solver. The TSA, embedded into the GA frame, defines the acceptable neighborhood region of parameters and screens out the poor-scoring individuals. Thus, the repeats of search are avoided and the amount of time-consuming electromagnetic simulations is largely reduced. Moreover, the whole design procedure is auto-controlled by programming the VBScript language. A slot patch antenna example is provided to verify the accuracy and efficiency of the proposed method.

  17. Resonance of Superconducting Microstrip Antenna with Aperture in the Ground Plane

    Directory of Open Access Journals (Sweden)

    S. Benkouda

    2013-08-01

    Full Text Available This paper presents a rigorous full-wave analysis of a high Tc superconducting rectangular microstrip antenna with a rectangular aperture in the ground plane. To include the effect of the superconductivity of the microstrip patch in the full-wave analysis, a complex surface impedance is considered. The proposed approach is validated by comparing the computed results with previously published data. Results showing the effect of the aperture on the resonance of the superconducting microstrip antenna are given.

  18. High-Directivity Antenna Array Based on Artificial Electromagnetic Metamaterials with Low Refractive Index

    Directory of Open Access Journals (Sweden)

    Zhigang Xiao

    2015-01-01

    Full Text Available Planar metamaterials (MTMs with low refractive index are proposed as a cover in a high-gain patch antenna array configuration. This MTMs array antenna has the following features: the number of array elements significantly decreases compared with the conventional array; the elements spacing is larger than a wave length by far; the feeding network is simpler. MTMs are made of two layers of periodic square metallic grids and placed above the feeding array. With the same aperture size, the directivity of MTMs-cover antenna array is higher than the conventional antenna array. The simulation results show that an array of 2 × 2 patch elements integrated with MTMs yields about 26 dB of directivity which is higher than that of conventional 8 × 8 patch array. Furthermore, on the condition of the same aperture size, an array patch with 4 × 4 elements integrated with the MTMs-cover has an equivalent gain compared with the conventional patch array with 16 × 16 array elements. Obviously, the former has a simpler feeding network and higher aperture efficiency. The experimental work has verified that the 2 × 2 array case and the measured results have good agreement with the simulation.

  19. Fabrication and impact performance of three-dimensionally integrated microstrip antennas with microstrip and coaxial feeding

    Science.gov (United States)

    Yao, Lan; Wang, Xin; Xu, Fujun; Zhao, Da; Jiang, Muwen; Qiu, Yiping

    2009-09-01

    A conformal load-bearing antenna structure (CLAS) combines the antenna into a composite structure such that it can carry the designed load while functioning as an antenna. In this paper, two types of new 3D integrated microstrip antennas (3DIMAs) with different feeding methods are designed to work at the radar L-band. Different from the conventional CLAS, the radiating patch and the ground plane of the 3DIMA are both composed of woven conductive wires and are bonded into the 3D composite physically by Z-yarns, greatly improving the damage tolerance of the antenna. The return loss of the coaxial-fed antenna is -13.15 dB with a resonant frequency of 1.872 GHz, while that of the microstrip-fed antenna is -31.50 dB with a resonant frequency of 1.33 GHz. Both of the 3DIMAs have similar radiation patterns to that of the traditionally designed microstrip antenna. In addition, an experimental investigation of the impact response of the coaxial-fed 3DIMA was carried out and the results showed the radiation pattern had almost no change even when the antenna received an impact energy of 15 J, exhibiting superior impact resistance to that of a conventional microstrip antenna.

  20. TLM modeling and system identification of optimized antenna structures

    Directory of Open Access Journals (Sweden)

    N. Fichtner

    2008-05-01

    Full Text Available The transmission line matrix (TLM method in conjunction with the genetic algorithm (GA is presented for the bandwidth optimization of a low profile patch antenna. The optimization routine is supplemented by a system identification (SI procedure. By the SI the model parameters of the structure are estimated which is used for a reduction of the total TLM simulation time. The SI utilizes a new stability criterion of the physical poles for the parameter extraction.

  1. Dual-polarization, wideband microstrip antenna array for airborne C-band SAR

    DEFF Research Database (Denmark)

    Granholm, Johan; Skou, Niels

    2000-01-01

    The paper describes the development of a C-band, dual linear polarization wideband antenna array, for use in the next-generation of the Danish airborne polarimetric synthetic aperture radar (SAR) system. The array is made of probe-fed, stacked microstrip patches. The design and performance...... of the basic stacked patch element, operating from 4.9 GHz to 5.7 GHz, and a 2×2 element test array of these, are described....

  2. A Compact Pentagonal Ring CPW-Fed Zeroth Order Resonating Antenna with Gain Enhancement

    Science.gov (United States)

    Gupta, Ashish; Chaudhary, Raghvendra Kumar

    2017-05-01

    In this work, a pentagonal ring CPW-fed zeroth order resonating (ZOR) antenna with gain enhancement is proposed. Gain enhancement is achieved by means of electromagnetic bandgap structures (EBG) loaded on patch. The proposed antenna is operated in series resonant mode, therefore resonance frequency is dominated by series parameters of the conventional CRLH transmission line. The antenna comprises of a circular patch which is imposed by interdigital capacitor and EBG structures. Meandered line inductor is connected between patch and pentagonal ground plane in order to ensure miniaturization using CRLH resonant approach. Measurement results shows that proposed antenna offers ZOR resonance at 2.7 GHz with 4.81 %, 10 dB fractional bandwidth. The antenna offers simulated gain of 1.63 dBi and 80.6 % radiation efficiency at ZOR frequency. Surface current distribution shows that how these CRLH - TL components responsible for origination of ZOR mode. Proposed antenna exhibits excellent radiation patterns with cross polarization level of -53 dB in the boresight direction.

  3. A Novel Performance Analysis of the Microstrip Antenna Printed on a Cylindrical Body

    Directory of Open Access Journals (Sweden)

    Amr M. Mahros

    2014-01-01

    Full Text Available Performance of a circular patch microstrip antenna is highly affected by the effective dielectric constant of a used substrate material. When the circular patch is conformed on a cylindrical body, the effective dielectric constant is changing with curvature due to the changing in the fringing field. Consequently, some of antenna parameters such as resonance frequency, input impedance, voltage standing wave ratio, return loss, quality factor, and antenna bandwidth are functions of curvature. In this work, we study the effect of curvature on the performance of circular patch microstrip antenna. A mathematical model for the antenna parameters as functions of curvature is also introduced. The model is applied in case of using two substrates of different refractive index values. By extension, the antenna performance was studied through simulation by using method of moments (MoM which is reliable in solving Maxwell’s integral equations in the frequency domain. The results from simulation compare very favorably with the described analytical results.

  4. Automated Spray Pothole Patching Truck

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    The RA-300 patcher, manufactured by Rosco Manufacturing, Madison, S.D., is a fully automated spray patching road maintenance vehicle, which fills potholes and cracks on the road. A operator can control all patching functions with the control panel and joystick from the safety and comfort of the truck cab.

  5. Smart antennas in aerospace applications

    NARCIS (Netherlands)

    Verpoorte, Jaco; Schippers, Harmen; Roeloffzen, C.G.H.; Marpaung, D.A.I.

    2010-01-01

    The interest in Smart Antennas for aerospace applications is growing. This paper describes smart antennas which can be used on aircraft. Two aerospace applications are discussed in more detail: a phased array antenna with optical beam forming and a large vibrating phased array antenna with

  6. Optimisation of Microstrip Antenna

    Directory of Open Access Journals (Sweden)

    H. El Hamchary

    1996-04-01

    Full Text Available When choosing the most appropriate microstrip antenna configuration for particular applications, the kind of excitation of the radiating element is an essential factor that requires careful considerations. For controlling the distribution of energy of the linear or planar array of elements and for coupling energy to the individual elements, a wide variety of feed mechanisms are available. In this paper, the coaxial antenna feeding is assumed and the best (optimised feeding is found. Then, antenna characteristics such as radiation pattern, return loss, input impedance, and VSWR are obtained.

  7. Introduction to smart antennas

    CERN Document Server

    Balanis, Constantine A

    2007-01-01

    As the growing demand for mobile communications is constantly increasing, the need for better coverage, improved capacity, and higher transmission quality rises. Thus, a more efficient use of the radio spectrum is required. Smart antenna systems are capable of efficiently utilizing the radio spectrum and is a promise for an effective solution to the present wireless systems' problems while achieving reliable and robust high-speed high-data-rate transmission. The purpose of this book is to provide the reader a broad view of the system aspects of smart antennas. In fact, smart antenna systems co

  8. New USS Microstrip Antenna Proposal Based Both On Ku And Ka Frequency New USSMA Ku Ka Band

    Directory of Open Access Journals (Sweden)

    Chafaa Hamrouni

    2017-09-01

    Full Text Available In this article we propose a Microstrip Antenna for Ultra Small Satellite USS telecommunication subsystem application in UWB Ku frequency band and Ka band. The designed MA is based on circular patch antenna. We process by minimizing and adjusting the MA dimension to lift the latch of bandwidth while maintaining quality performance of other properties. We have developed a studied geometric shape and used tricks to design them. Obtained antenna feds by microstrip line and the ground plane. Antenna feed elements are placed on the same plate to reduce the spatial dimension. Successful results are presented to validate function of proposed design and its precision operating at high frequencies.

  9. Low-Cost Planar MM-Wave Phased Array Antenna for Use in Mobile Satellite (MSAT) Platforms

    DEFF Research Database (Denmark)

    Ojaroudiparchin, Naser; Shen, Ming; Pedersen, Gert F.

    2015-01-01

    In this paper, a compact 8×8 phased array antenna for mobile satellite (MSAT) devices is designed and investigated. 64-elements of 22 GHz patch antennas with coaxial-probe feeds have been used for the proposed planar design. The antenna is designed on a low-cost FR4 substrate with thickness, diel...... of simple configuration, low-cost, low-profile, and easy fabrication. Simulations have been done to validate the feasibility of the proposed phased array antenna for MSAT applications....

  10. Low profile conformal antenna arrays on high impedance substrate

    CERN Document Server

    Singh, Hema; Jha, Rakesh Mohan

    2016-01-01

    This book presents electromagnetic (EM) design and analysis of dipole antenna array over high impedance substrate (HIS). HIS is a preferred substrate for low-profile antenna design, owing to its unique boundary conditions. Such substrates permit radiating elements to be printed on them without any disturbance in the radiation characteristics. Moreover HIS provides improved impedance matching, enhanced bandwidth, and increased broadside directivity owing to total reflection from the reactive surface and high input impedance. This book considers different configurations of HIS for array design on planar and non-planar high-impedance surfaces. Results are presented for cylindrical dipole, printed dipole, and folded dipole over single- and double-layered square-patch-based HIS and dogbone-based HIS. The performance of antenna arrays is analyzed in terms of performance parameters such as return loss and radiation pattern. The design presented shows acceptable return loss and mainlobe gain of radiation pattern. Thi...

  11. A Compact Printed Quadruple Band-Notched UWB Antenna

    Directory of Open Access Journals (Sweden)

    Xiaoyin Li

    2013-01-01

    Full Text Available A novel compact coplanar waveguide- (CPW- fed ultrawideband (UWB printed planar volcano-smoke antenna (PVSA with four band-notches for various wireless applications is proposed and demonstrated. The low-profile antenna consists of a C-shaped parasitic strip to generate a notched band at 8.01~8.55 GHz for the ITU band, two C-shaped slots, and an inverted U-shaped slot etched in the radiator patch to create three notched bands at 5.15~5.35 GHz, 5.75~5.85 GHz, and 7.25~7.75 GHz for filtering the WLAN and X-band satellite signals. Simulated and measured results both confirm that the proposed antenna has a broad bandwidth of 3.1~12 GHz with VSWR < 2 and good omnidirectional radiation patterns with four notched-bands.

  12. Slotted Circularly Polarized Microstrip Antenna for RFID Application

    Directory of Open Access Journals (Sweden)

    S. Kumar

    2017-12-01

    Full Text Available A single layer coaxial fed rectangular microstrip slotted antenna for circular polarization (CP is proposed for radio frequency identification (RFID application. Two triangular shaped slots and one rectangular slot along the diagonal axis of a square patch have been embedded. Due to slotted structure along the diagonal axis and less surface area, good quality of circular polarization has been obtained with the reduction in the size of microstrip antenna by 4.04 %. Circular polarization radiation performance has been studied by size and angle variation of diagonally slotted structures. The experimental result found for 10-dB return loss is 44 MHz with 10MHz of 3dB Axial Ratio (AR bandwidth respectively at the resonant frequency 910 MHz. The overall proposed antenna size including the ground plane is 80 mm x 80 mm x 4.572 mm.

  13. Antennas from theory to practice

    CERN Document Server

    Huang, Yi

    2008-01-01

    Practical, concise and complete reference for the basics of modern antenna design Antennas: from Theory to Practice discusses the basics of modern antenna design and theory. Developed specifically for engineers and designers who work with radio communications, radar and RF engineering, this book offers practical and hands-on treatment of antenna theory and techniques, and provides its readers the skills to analyse, design and measure various antennas. Key features: Provides thorough coverage on the basics of transmission lines, radio waves and propag

  14. Dielectric Covered Planar Antennas

    Science.gov (United States)

    Llombart Juan, Nuria (Inventor); Lee, Choonsup (Inventor); Chattopadhyay, Goutam (Inventor); Gill, John J. (Inventor); Skalare, Anders J. (Inventor); Siegel, Peter H. (Inventor)

    2014-01-01

    An antenna element suitable for integrated arrays at terahertz frequencies is disclosed. The antenna element comprises an extended spherical (e.g. hemispherical) semiconductor lens, e.g. silicon, antenna fed by a leaky wave waveguide feed. The extended spherical lens comprises a substantially spherical lens adjacent a substantially planar lens extension. A couple of TE/TM leaky wave modes are excited in a resonant cavity formed between a ground plane and the substantially planar lens extension by a waveguide block coupled to the ground plane. Due to these modes, the primary feed radiates inside the lens with a directive pattern that illuminates a small sector of the lens. The antenna structure is compatible with known semiconductor fabrication technology and enables production of large format imaging arrays.

  15. Antenna pattern study

    Science.gov (United States)

    Harper, Warren

    1988-01-01

    Prediction of antenna radiation patterns has long been an important function in the design of command, communication, and tracking systems for rocket vehicles and spacecraft. An acceptable degree of assurance that a radio link will provide the required quality of data or certainty of correct command execution must be acquired by some means if the system is to be certified as reliable. Two methods have been used to perform this function: (1) Theoretical analysis, based on the known properties of basic antenna element types and their behavior in the presence of conductive structures of simple shape, and (2) Measurement of the patterns on scale models of the spacecraft or rocket vehicle on which the antenna is located. Both of these methods are ordinarily employed in the antenna design process.

  16. Measured Variation in performance of handheld antennas for a large number of test persons

    DEFF Research Database (Denmark)

    Pedersen, Gert Frølund; Nielsen, Jesper Ødum; Olesen, Kim

    This work investigates the variation in the mean effective gain (MEG) for a large number of test persons in order to find how much the difference in anatomy and persons who wear glasses, etc., changes the MEG (i.e., the received signal power with respect to a reference). The evaluation was carried......” and a person present is on the average 3 dB for a directive patch antenna, 6 dB for a whip antenna and 10 dB for a helical antenna...

  17. Practical Considerations Relative to the Design and Manufacture of Microstrip Antennas

    Science.gov (United States)

    1991-04-01

    Resonance characteristics of a rectangular nmicrosirip antenna. Proc. Workshop on Printed Circuit Antenna Tech.. New Mexico State University. Oct 1979...patch was measiured on an HIP 8510 netwo k 39 analyzer and these datr are do(-;Iimented i1i Appendix A. hi this ser’tlo . Pib iewastrmed resl lf will he...New Mexico State Univ., Oct 1979, pp. 7/1-20. 16, Chang. D.C. and Kuester, E.F. (1979) Resonance Characteristics of a Rectangular Microsirip Antenna

  18. Characteristics of a high T{sub c} superconducting rectangular microstrip patch on uniaxially anisotropic substrate

    Energy Technology Data Exchange (ETDEWEB)

    Benkouda, Siham; Messai, Abderraouf [Electronics Department, University of Constantine 1, 25000 Constantine (Algeria); Amir, Mounir; Bedra, Sami [Electronics Department, University of Batna, 05000 Batna (Algeria); Fortaki, Tarek, E-mail: t_fortaki@yahoo.fr [Electronics Department, University of Batna, 05000 Batna (Algeria)

    2014-07-15

    Highlights: • We model a microstrip antenna with anisotropic substrate and superconductor patch. • The extended full-wave analysis is used to solve for the antenna characteristics. • The accuracy of the method is checked by comparing our results with published data. • Uniaxial anisotropy affects the resonant characteristics of the antenna. • Patch on uniaxial substrate is more advantageous than the one on isotropic medium. - Abstract: Resonant characteristics of a high T{sub c} superconducting rectangular microstrip patch printed on uniaxially anisotropic substrate are investigated using a full-wave spectral analysis in conjunction with the complex resistive boundary condition. The uniaxial medium shows anisotropy of an electric type as well as anisotropy of a magnetic type. Both permittivity and permeability tensors of the substrate are included in the formulation of the dyadic Green’s function of the problem. The accuracy of the analysis is tested by comparing the computed results with previously published data for several anisotropic substrate materials. Numerical data of the resonant frequency and bandwidth as a function of electric anisotropy ratio are presented. Variations of the resonant frequency and bandwidth with the magnetic anisotropy ratio are also given. Finally, results showing the influence of the temperature on the resonant frequency and quality factor of the high T{sub c} superconducting rectangular microstrip patch on a uniaxial substrate are also given.

  19. A Novel Manufacturing Process for Compact, Low-Weight and Flexible Ultra-Wideband Cavity Backed Textile Antennas.

    Science.gov (United States)

    Van Baelen, Dries; Lemey, Sam; Verhaevert, Jo; Rogier, Hendrik

    2018-01-03

    A novel manufacturing procedure for the fabrication of ultra-wideband cavity-backed substrate integrated waveguide antennas on textile substrates is proposed. The antenna cavity is constructed using a single laser-cut electrotextile patch, which is folded around the substrate. Electrotextile slabs protruding from the laser-cut patch are then vertically folded and glued to form the antenna cavity instead of rigid metal tubelets to implement the vertical cavity walls. This approach drastically improves mechanical flexibility, decreases the antenna weight to slightly more than 1 g and significantly reduces alignment errors. As a proof of concept, a cavity-backed substrate integrated waveguide antenna is designed and realized for ultra-wideband operation in the [5.15-5.85] GHz band. Antenna performance is validated in free space as well as in two on body measurement scenarios. Furthermore, the antenna's figures of merit are characterized when the prototype is bent at different curvature radii, as commonly encountered during deployment on the human body. Also the effect of humidity content on antenna performance is studied. In all scenarios, the realized antenna covers the entire operating frequency band, meanwhile retaining a stable radiation pattern with a broadside gain above 5 dBi, and a radiation efficiency of at least 70%.

  20. Analysis of a Compact Wideband Slotted Antenna for Ku Band Applications

    Directory of Open Access Journals (Sweden)

    M. R. Ahsan

    2014-01-01

    Full Text Available The design procedure and physical module of a compact wideband patch antenna for Ku band application are presented in this paper. Finite element method based on 3D electromagnetic field solver has been utilized for the designing and analyzing process of proposed microstrip line fed modified E-H shaped electrically small patch antenna. After successful completion of the design process through various simulations, the proposed antenna has been fabricated on printed circuit board (PCB and its characteristics have been studied. The parameters of the proposed antenna prototype have been measured in standard far-field rectangular shape anechoic measurement compartment. It is apparent from the measured antenna parameters that the proposed antenna achieved almost stable variation of radiation pattern over the entire operational band with 1380 MHz of -10 dB return loss bandwidth. The maximum gain of 7.8 dBi and 89.97% average efficiency within the operating band from 17.15 GHz to 18.53 GHz ensure the suitability of the proposed antenna for Ku band applications.

  1. Dual Band Metamaterial Antenna For LTE/Bluetooth/WiMAX System.

    Science.gov (United States)

    Hasan, Md Mehedi; Faruque, Mohammad Rashed Iqbal; Islam, Mohammad Tariqul

    2018-01-19

    A compact metamaterial inspired antenna operate at LTE, Bluetooth and WiMAX frequency band is introduced in this paper. For the lower band, the design utilizes an outer square metallic strip forcing the patch to radiate as an equivalent magnetic-current loop. For the upper band, another magnetic current loop is created by adding metamaterial structure near the feed line on the patch. The metamaterial inspired antenna dimension of 42 × 32 mm 2 compatible to wireless devices. Finite integration technique based CST Microwave Studio simulator has been used to design and numerical investigation as well as lumped circuit model of the metamaterial antenna is explained with proper mathematical derivation. The achieved measured dual band operation of the conventional antenna are sequentially, 0.561~0.578 GHz, 2.346~2.906 GHz, and 2.91~3.49 GHz, whereas the metamaterial inspired antenna shows dual-band operation from 0.60~0.64 GHz, 2.67~3.40 GHz and 3.61~3.67 GHz, respectively. Therefore, the metamaterial antenna is applicable for LTE and WiMAX applications. Besides, the measured metamaterial antenna gains of 0.15~3.81 dBi and 3.47~3.75 dBi, respectively for the frequency band of 2.67~3.40 GHz and 3.61~3.67 GHz.

  2. ULTRA-WIDEBAND CO-LOCATED DIVERSITY ANTENNA FOR ENHANCING CHANNEL CAPACITY

    Directory of Open Access Journals (Sweden)

    Prajakta Kulkarni

    2016-12-01

    Full Text Available In this paper, we have presented a novel approach of diversity antenna with high isolation which improves the channel capacity in wireless communication application. We have proposed diversity antenna which consists of two billhook shaped patch elements along with rectangular slot inserted in it and a narrow semi-circular shape on the ground plane. Ultra-wideband (UWB diversity antenna elements are placed orthogonal to each other to obtain high isolation, also achieve the polarization and pattern diversity. We have calculated the patch size of diversity antenna is 33×18mm in compactness condition. In this paper, the diversity antenna is implemented, fabricated and its parameters are evaluated by CST Studio. The proposed technique of UWBMIMO (Multiple Input Multiple Output antenna achieved larger bandwidth, low mutual coupling and envelope correlation coefficient (ECC over the UWB frequency band. For diversity antenna, we have observed diversity performance factors like diversity gain, capacity loss, and ECC. With the help of these parameters, we have shown improvement in the channel capacity. Through our simulation and experimental results, it is observed that our new proposed technique is better than existing methods.

  3. Performance of a Planar Leaky-Wave Slit Antenna for Different Values of Substrate Thickness

    Directory of Open Access Journals (Sweden)

    Niamat Hussain

    2017-10-01

    Full Text Available This paper presents the performance of a planar, low-profile, and wide-gain-bandwidth leaky-wave slit antenna in different thickness values of high-permittivity gallium arsenide substrates at terahertz frequencies. The proposed antenna designs consisted of a periodic array of 5 × 5 metallic square patches and a planar feeding structure. The patch array was printed on the top side of the substrate, and the feeding structure, which is an open-ended leaky-wave slot line, was etched on the bottom side of the substrate. The antenna performed as a Fabry-Perot cavity antenna at high thickness levels (H = 160 μm and H = 80 μm, thus exhibiting high gain but a narrow gain bandwidth. At low thickness levels (H = 40 μm and H = 20 μm, it performed as a metasurface antenna and showed wide-gain-bandwidth characteristics with a low gain value. Aside from the advantage of achieving useful characteristics for different antennas by just changing the substrate thickness, the proposed antenna design exhibited a low profile, easy integration into circuit boards, and excellent low-cost mass production suitability.

  4. Design of a compact tuning fork-shaped notched ultrawideband antenna for wireless communication application.

    Science.gov (United States)

    Shakib, M N; Moghavvemi, M; Mahadi, W N L

    2014-01-01

    A new compact planar notched ultrawideband (UWB) antenna is designed for wireless communication application. The proposed antenna has a compact size of 0.182λ × 0.228λ × 0.018λ where λ is the wavelength of the lowest operating frequency. The antenna is comprised of rectangular radiating patch, ground plane, and an arc-shaped strip in between radiating patch and feed line. By introducing a new Tuning Fork-shaped notch in the radiating plane, a stopband is obtained. The antenna is tested and measured. The measured result indicated that fabricated antenna has achieved a wide bandwidth of 4.33-13.8 GHz (at -10 dB return loss) with a rejection frequency band of 5.28-6.97 GHz (WiMAX, WLAN, and C-band). The effects of the parameters of the antenna are discussed. The experiment results demonstrate that the proposed antenna can well meet the requirement for the UWB communication in spite of its compactness and small size.

  5. A New Agile Radiating System Called Electromagnetic Band Gap Matrix Antenna

    Directory of Open Access Journals (Sweden)

    Hussein Abou Taam

    2014-01-01

    Full Text Available Civil and military applications are increasingly in need for agile antenna devices which respond to wireless telecommunications, radars, and electronic warfare requirements. The objective of this paper is to design a new agile antenna system called electromagnetic band gap (EBG matrix. The working principle of this antenna is based on the radiating aperture theory and constitutes the subject of an accepted CNRS patent. In order to highlight the interest and the originality of this antenna, we present a comparison between it and a classical patch array only for the (one-dimensional 1D configuration by using a rigorous full wave simulation (CST Microwave software. In addition, EBG matrix antenna can be controlled by specific synthesis algorithms. These algorithms use inside their; optimization loop an analysis procedure to evaluate the radiation pattern. The analysis procedure is described and validated at the end of this paper.

  6. A Novel CPW-Fed UWB Antenna with Band-Stop Function

    Directory of Open Access Journals (Sweden)

    Huaming Chen

    2014-01-01

    Full Text Available A novel coplanar waveguide-fed (CPW ultrawideband (UWB antenna with band-stop function is presented in this paper. The proposed antenna comprises a CPW-fed slot rectangular patch with an open stub ground plane, and two inverted L-shaped strip conductors are fabricated on the back plane. The overall size of the antenna is 25 × 25 × 1.6 mm2, and it achieves good impedance matching and radiation gain. Simulated and measured results show that the designed antenna operates at 2.9 GHz–13.08 GHz with band rejection in the frequency band of 7.7 GHz–9.05 GHz for satellite applications, and the proposed antenna is suitable for UWB wireless communication applications.

  7. A new design of an S/X dual band circular slot antenna for radar applications.

    Science.gov (United States)

    Ghnimi, Said; Wali, Rawia; Gharsallh, Ali; Razban, Tchanguiz

    2013-01-01

    A novel design of dual-band slot antenna with a circular patch for radar applications is presented and studied. It is fed by a micro-strip line and built on a FR-4 substrate with a whole size of 18 x 30 mm2. A dual band printed antenna is created by introducing slots on the radiating element. By this, two bandwidth, covering C and X band, are achieved. In order to obtain a good fundamental antenna design, the initial studies were carried out theoretically, using CST Microwave Studio simulation software. In this case, the frequency range at return loss antenna has good radiation characteristics and stable gains over the whole operating bands. A prototype of antenna is fabricated and tested. Experimental data show good agreement between simulated and measured results.

  8. A Compact Wideband Stacked Antenna for the Tri-Band GPS Applications

    Directory of Open Access Journals (Sweden)

    Maher M. Abd Elrazzak

    2008-01-01

    Full Text Available A compact wideband stacked patch antenna is presented for the applications of GPS systems. This antenna covers the L1, L2, and L5 GPS bands of operating frequencies 1.575, 1.227, and 1.176 GHz, respectively. High permittivity dielectric materials are used to minimize the antenna dimensions. The obtained antenna is of dimensions 32×18×2.117 mm. To verify the design, the time dependence field distribution, the scattering parameters, and the radiation pattern are presented. The scattering parameters show that the antenna operates at the GPS frequencies with lower than −10 dB. The finite difference time domain (FDTM with the perfect matched layer (PML is used in the present analysis.

  9. *New*: CRITICAL Windows Security patch

    CERN Multimedia

    2003-01-01

    On 10 September 2003, Microsoft issued a new CRITICAL security patch, MS03-039. It must be URGENTLY applied on ALL WINDOWS systems, which are not centrally managed for security patches. This includes Experiment computers, Home computers and Windows Portable and Desktop systems not running NICE. Details of the security hole and patch for MS03-039 (which also includes MS03-026) are at: http://cern.ch/it-div/news/hotfix-MS03-039.asp http://www.microsoft.com/technet/security/bulletin/MS03-039.asp

  10. *New* CRITICAL Windows Security patch

    CERN Multimedia

    2003-01-01

    On 10 September 2003, Microsoft issued a new CRITICAL security patch, MS03-039. It must be URGENTLY applied on ALL WINDOWS systems, which are not centrally managed for security patches. This includes Experiment computers, Home computers and Windows Portable and Desktop systems not running NICE. Details of the security hole and patch for MS03-039 (which also includes MS03-026) are at: http://cern.ch/it-div/news/hotfix-MS03-039.asp http://www.microsoft.com/technet/security/bulletin/MS03-039.asp

  11. Asphyxiation with a Fentanyl Patch

    Directory of Open Access Journals (Sweden)

    Aaron S. Mansfield

    2013-05-01

    Full Text Available Narcotics are frequently prescribed to alleviate pain in patients with serious medical illnesses such as cancer. Because of their nonoral route of administration, fentanyl patches are now being frequently prescribed. However, the widespread use of fentanyl patches has been associated with medication errors and misuse [Butts and Jatoi: J Opioid Manag 2011;7:35-45]. The transdermal delivery of fentanyl may lead to unusual, unanticipated complications. Herein, we describe a fentanyl patch complication, which, to our knowledge, has not been previously reported.

  12. Relative vs Absolute Antenna Calibrations: How, when, and why do they differ? A Comparison of Antenna Calibration Catalogs

    Science.gov (United States)

    Mader, G. L.; Bilich, A. L.

    2013-12-01

    (PCV), and full phase center correction (PCC). We analyze these differences in the context of time, to understand potential calibration technique changes over time. We also view the differences through the lens of antenna type (e.g. patch antenna, chokering, integrated receiver/antenna unit) to understand how the calibration technique and/or nearfield test environment may affect the calibration values.

  13. Design of a Microstrip Bowtie Antenna for Indoor Radio-Communications

    Directory of Open Access Journals (Sweden)

    Fraga-Rosales Hector

    2017-01-01

    Full Text Available In this paper, a microstrip bowtie patch antenna (MBPA for wireless indoor communications is carried out. Here, a microstrip transmission-line feed network was designed in order to match the MBPA. The proposed antenna uses a ground plane with the aim of narrowing down the back lobes in comparison with bowtie sheet antennas, which radiation pattern is omni-directional. The far-field pattern of the antenna was simulated using a finite-element numerical algorithm and obtained by interpolation employing near-field equipment. The experimental results are described in detail intending to agree well with the simulated predictions. The antenna was designed, measured and built and its far field performance was evaluated with a 2.11 GHz resonant frequency. The azimuth and elevation antenna patterns, antenna gain and, the matching frequency were the main parameters obtained to analyze the antenna behaviour. The antenna has a gain approximately equal to 8.77 dBi and its beam-widths are higher than 100° in E plane.

  14. Design and synthesis of flexible switching 1 × 2 antenna array on Kapton substrate

    Science.gov (United States)

    Georges Rabobason, Yvon; Rigas, Grigorios; Swaisaenyakorn, Srijittar; Mirkhaydarov, Bobur; Ravelo, Blaise; Shkunov, Maxim; Young, Paul; Benjelloun, Nabil

    2016-06-01

    Flexible front- and back-end RF/analogue system antennas were recently emerged. However, little flexible antenna system design is available so far, in planar hybrid technology with surface mounted components. This paper describes the design feasibility of flexible switching 1 × 2 antenna array system. It acts as a switching antenna implemented in hexapole configuration. The system is comprised of a key element RF switch terminated by two identical patch antennas associated to half-wave elementary transmission lines (TLs). A detailed theory illustrating the global S-parameter model determination in function of the given RF-switch return and insertion losses is established. In difference to the conventional microwave circuit theory, the proposed equivalent S-parameter model is originally built with the non-standard optimized antenna load. Thus, the synthesis method of the terminal antenna input impedance and the output access line characteristic impedance is formulated in function of the specified return and optimal transmission losses. The design method and theoretical approach feasibility is verified with the demonstrator of flexible switching 1 × 2 antenna array printed on Kapton substrate. The circuit prototype is implemented in hybrid planar technology integrating patch antenna operating at about 6 GHz and a packaged GaAs RF switch associated to the RF/DC signal decoupling accessory mounted surface components. Simulations of the designed circuit transmission and isolation losses from 5.5 GHz to 7 GHz were carried out by using the commercial RF switch S-parameter touchstone model provided by the manufacturer. The simulated and measured return losses are compared and discussed. Then, the measured radiation patterns confirm the proposed switched antenna concept feasibility.

  15. Directivity of Antenna Arrays

    Science.gov (United States)

    Bulgakova, A. A.; Gorobets, N. N.; Katrich, V. A.; Lyashchenko, V. A.

    2016-12-01

    Purpose: Theoretical investigation of directive gains of linear and planar antenna arrays depending on the distance between radiators and wavelength. Design/methodology/approach: Computing methods in applied mathematics in MathCad were used to calculate the twofold integrals of the radiation pattern over power throughout the whole space observed, defining the directivity in the most general terms. Patterns of radiators, i. e. elements of antenna arrays, are specified by mathematical models. The calculation accounts for the subintegral fast oscillating function. Findings: Calculations and analysis of a directive gain according to the number of radiators and distances between them in fractions of wavelength are made. It is shown that at the ratio of distance between radiators to wave-length being d/λ =0.5 the directivity of array of isotropic radiators is 1.5N², N - number of radiators. When increasing the d/λ to 0.65÷0.97 the directivity increases according to the law close to the linear one up to the maximum possible value for the specified number of radiators. With the increase of d/λ to the values greater than one, the directivity is significantly reduced (the “blinding” effect of non-phased antenna arrays) and its dependence with the growth of d/λ is decaying and oscillating in character. By that, the transfer function of antenna arrays has some vital difference from the transfer function of continuous antennas. Conclusions: Antenna arrays distort the waveform and spectrum of radiated and received signals as a result of irregular changes of their directivity depending on wavelength. The detected “blinding” effect of non-phased antenna arrays of large electrical dimensions must be taken into account in wideband and superwideband radio-electronics systems, especially in radio astronomy, telecommunications systems and superwideband radar.

  16. Flu Vaccine Skin Patch Tested

    Science.gov (United States)

    ... Past Issues Subscribe September 2017 Print this issue Flu Vaccine Skin Patch Tested En español Send us ... Each year, millions of people nationwide catch the flu. The best way to protect yourself is to ...

  17. Antenna for Ultrawideband Channel Sounding

    DEFF Research Database (Denmark)

    Zhekov, Stanislav Stefanov; Tatomirescu, Alexandru; Pedersen, Gert F.

    2016-01-01

    A novel compact antenna for ultrawideband channel sounding is presented. The antenna is composed of a symmetrical biconical antenna modified by adding a cylinder and a ring to each cone. A feeding coaxial cable is employed during the simulations in order to evaluate and reduce its impact on the a......A novel compact antenna for ultrawideband channel sounding is presented. The antenna is composed of a symmetrical biconical antenna modified by adding a cylinder and a ring to each cone. A feeding coaxial cable is employed during the simulations in order to evaluate and reduce its impact...

  18. Suspended animation for delayed resuscitation.

    Science.gov (United States)

    Safar, Peter J; Tisherman, Samuel A

    2002-04-01

    'Suspended animation for delayed resuscitation' is a new concept for attempting resuscitation from cardiac arrest of patients who currently (totally or temporarily) cannot be resuscitated, such as traumatic exsanguination cardiac arrest. Suspended animation means preservation of the viability of brain and organism during cardiac arrest, until restoration of stable spontaneous circulation or prolonged artificial circulation is possible. Suspended animation for exsanguination cardiac arrest of trauma victims would have to be induced within the critical first 5 min after the start of cardiac arrest no-flow, to buy time for transport and resuscitative surgery (hemostasis) performed during no-flow. Cardiac arrest is then reversed with all-out resuscitation, usually requiring cardiopulmonary bypass. Suspended animation has been explored and documented as effective in dogs in terms of long-term survival without brain damage after very prolonged cardiac arrest. In the 1990s, the Pittsburgh group achieved survival without brain damage in dogs after cardiac arrest of up to 90 min no-flow at brain (tympanic) temperature of 10 degrees C, with functionally and histologically normal brains. These studies used emergency cardiopulmonary bypass with heat exchanger or a single hypothermic saline flush into the aorta, which proved superior to pharmacologic strategies. For the large number of normovolemic sudden cardiac death victims, which currently cannot be resuscitated, more research in large animals is needed.

  19. Formulation Optimization of Arecoline Patches

    Directory of Open Access Journals (Sweden)

    Pao-Chu Wu

    2014-01-01

    Full Text Available The response surface methodology (RSM including polynomial equations has been used to design an optimal patch formulation with appropriate adhesion and flux. The patch formulations were composed of different polymers, including Eudragit RS 100 (ERS, Eudragit RL 100 (ERL and polyvinylpyrrolidone K30 (PVP, plasticizers (PEG 400, and drug. In addition, using terpenes as enhancers could increase the flux of the drug. Menthol showed the highest enhancement effect on the flux of arecoline.

  20. Patch photopatch test at Manipal

    OpenAIRE

    Panja Arindrajit; Srinivas C; Shenoy S; Balachandran C

    1994-01-01

    Patch and photopatch testing was performed on 55 patients with history of photosensitivity using Scandanavian photo patch test antigens obtained from Chemotechnique Diagnostics AB Sweden. The commonest reactions were seen to perfume mix 4 (21.0%), PABA 3 (15.78%), promethazine hydrochloride 3 (15.78%), chlorpromazine hydrochloride 3 (15.78%), balsam of peru 2 (10.52%), usnic acid, hexachlorophane, musk ambrette and 6 methyl coumarin showed 1 positive reactio...

  1. Design of a dual linear polarization antenna using split ring resonators at X-band

    Directory of Open Access Journals (Sweden)

    S. Ahmed

    2017-11-01

    Full Text Available Dual linear polarization microstrip antenna configurations are very suitable for high-performance satellites, wireless communication and radar applications. This paper presents a new method to improve the co-cross polarization discrimination (XPD for dual linear polarized microstrip antennas at 10 GHz. For this, three various configurations of a dual linear polarization antenna utilizing metamaterial unit cells are shown. In the first layout, the microstrip patch antenna is loaded with two pairs of spiral ring resonators, in the second model, a split ring resonator is placed between two microstrip feed lines, and in the third design, a complementary split ring resonators are etched in the ground plane. This work has two primary goals: the first is related to the addition of metamaterial unit cells to the antenna structure which permits compensation for an asymmetric current distribution flow on the microstrip antenna and thus yields a symmetrical current distribution on it. This compensation leads to an important enhancement in the XPD in comparison to a conventional dual linear polarized microstrip patch antenna. The simulation reveals an improvement of 7.9, 8.8, and 4 dB in the E and H planes for the three designs, respectively, in the XPD as compared to the conventional dual linear polarized patch antenna. The second objective of this paper is to present the characteristics and performances of the designs of the spiral ring resonator (S-RR, split ring resonator (SRR, and complementary split ring resonator (CSRR metamaterial unit cells. The simulations are evaluated using the commercial full-wave simulator, Ansoft High-Frequency Structure Simulator (HFSS.

  2. Design of a dual linear polarization antenna using split ring resonators at X-band

    Science.gov (United States)

    Ahmed, Sadiq; Chandra, Madhukar

    2017-11-01

    Dual linear polarization microstrip antenna configurations are very suitable for high-performance satellites, wireless communication and radar applications. This paper presents a new method to improve the co-cross polarization discrimination (XPD) for dual linear polarized microstrip antennas at 10 GHz. For this, three various configurations of a dual linear polarization antenna utilizing metamaterial unit cells are shown. In the first layout, the microstrip patch antenna is loaded with two pairs of spiral ring resonators, in the second model, a split ring resonator is placed between two microstrip feed lines, and in the third design, a complementary split ring resonators are etched in the ground plane. This work has two primary goals: the first is related to the addition of metamaterial unit cells to the antenna structure which permits compensation for an asymmetric current distribution flow on the microstrip antenna and thus yields a symmetrical current distribution on it. This compensation leads to an important enhancement in the XPD in comparison to a conventional dual linear polarized microstrip patch antenna. The simulation reveals an improvement of 7.9, 8.8, and 4 dB in the E and H planes for the three designs, respectively, in the XPD as compared to the conventional dual linear polarized patch antenna. The second objective of this paper is to present the characteristics and performances of the designs of the spiral ring resonator (S-RR), split ring resonator (SRR), and complementary split ring resonator (CSRR) metamaterial unit cells. The simulations are evaluated using the commercial full-wave simulator, Ansoft High-Frequency Structure Simulator (HFSS).

  3. Patch photopatch test at Manipal

    Directory of Open Access Journals (Sweden)

    Panja Arindrajit

    1994-01-01

    Full Text Available Patch and photopatch testing was performed on 55 patients with history of photosensitivity using Scandanavian photo patch test antigens obtained from Chemotechnique Diagnostics AB Sweden. The commonest reactions were seen to perfume mix 4 (21.0%, PABA 3 (15.78%, promethazine hydrochloride 3 (15.78%, chlorpromazine hydrochloride 3 (15.78%, balsam of peru 2 (10.52%, usnic acid, hexachlorophane, musk ambrette and 6 methyl coumarin showed 1 positive reaction each (5.26% suggesting either phototoxicity or photo sensitization. Patch and photo patch test positive reaction suggesting allergic sensitisation was seen to balsam of peru 3 (23.0% perfume mix 3 (23.0% promethazine hydrochloride 2 (15.3% and PABA, 6 methyl coumarin, tribromosalicylanilide, atranorin and wood mix showed positive reaction in one case each (7.69%. We conclude that photoxic or photo allergic reaction is a problem in India and patch photo patch test should be performed in all cases of idiopathic light eruptions to rule out photo sensitisation and in cases where photo sensitivity of exogenous origin is suspected.

  4. Integrated filtering in reconfigurable planar phased-array antennas with spurious harmonic suppression

    NARCIS (Netherlands)

    Cifola, L.; Gerini, G.; Monni, S.; Berg, S. van den; Water, F. van de

    2013-01-01

    In the present work, the possibility to integrate filtering functionalities in a phased-array antenna at radiating element level is investigated. The filtenna concept has been applied to an X-band phased array of slot-fed patches. An effective strategy for the suppression of spurious harmonics,

  5. A Small Planar Antenna for 4G Mobile Phone Application

    Directory of Open Access Journals (Sweden)

    Hu Jian-rong

    2016-01-01

    Full Text Available The analysis and design of a small planar multiband antenna operating in the 4G frequency bands are presented. The numerical and experimental results demonstrated that the proposed antenna satisfies the requirement of 6 dB return loss for the impedance bandwidth of the LTE700/LTE2300/LTE2500 and WiMAX3500 bands. The gains at 750 MHz/2.3 GHz/2.6 GHz/3.5 GHz are 2.1 dBi/4.9 dBi/4.7 dBi/4.3 dBi, respectively. The measured radiation patterns verify the suitability of the antenna to be employed in mobile phones. The dimensions of the radiant patch are 49 × 10 mm2. The proposed antenna can be easily fabricated and customized to various 4G mobile phones as a compact internal antenna.

  6. A Minkowski Fractal Circularly Polarized Antenna for RFID Reader

    Directory of Open Access Journals (Sweden)

    Yanzhong Yu

    2014-11-01

    Full Text Available A design of fractal-like antenna with circular polarization for radio frequency identification (RFID reader applications is presented in this article. The modified Minkowski fractal structure is adopted as radiating patch for size reduction and broadband operation. A corner-truncated technology and a slot-opened method are employed to realize circular polarization and improve the gain of the proposed antenna, respectively. The proposed antenna is analyzed and optimized by HFSS. Return loss and maximum gain of the optimized antenna achieve to -22.2 dB and 1.12 dB at 920 MHz, respectively. The optimized design has an axial ratio (AR of 1.2 dB at central frequency of 920 MHz and impedance bandwidth (S11<=-10 dB of 40 MHz (4.3 %. Its input impedance is (57.9-j2.6 W that is close to input impedance of coaxial line (50 W. Numerical results demonstrate that the optimized antenna exhibits acceptable performances and may satisfy requirements of RFID reader applications.

  7. Design Studies of Ultra-Wideband Microstrip Antennas with a Small Capacitive Feed

    Directory of Open Access Journals (Sweden)

    Veeresh G. Kasabegoudar

    2007-01-01

    Full Text Available The design of an ultra-wideband microstrip patch antenna with a small coplanar capacitive feed strip is presented. The proposed rectangular patch antenna provides an impedance bandwidth of nearly 50%, and has stable radiation patterns for almost all frequencies in the operational band. Results presented here show that such wide bandwidths are also possible for triangular and semiellipse geometries with a similar feed arrangement. The proposed feed is a very small strip placed very close to the radiator on a substrate above the ground plane. Shape of the feed strip can also be different, so long as the area is not changed. Experimental results agree with the simulated results. Effects of key design parameters such as the air gap between the substrate and the ground plane, the distance between radiator patch and feed strip, and the dimensions of the feed strip on the input characteristics of the antenna have been investigated and discussed. As demonstrated here, the proposed antenna can be redesigned for any frequency in the L-, S-, C-, or X-band. A design criterion for the air gap has been empirically obtained to enable maximum antenna bandwidth for all these operational frequencies.

  8. Mode Matching for Optical Antennas.

    Science.gov (United States)

    Feichtner, Thorsten; Christiansen, Silke; Hecht, Bert

    2017-11-24

    The emission rate of a point dipole can be strongly increased in the presence of a well-designed optical antenna. Yet, optical antenna design is largely based on radio-frequency rules, ignoring, e.g., Ohmic losses and non-negligible field penetration in metals at optical frequencies. Here, we combine reciprocity and Poynting's theorem to derive a set of optical-frequency antenna design rules for benchmarking and optimizing the performance of optical antennas driven by single quantum emitters. Based on these findings a novel plasmonic cavity antenna design is presented exhibiting a considerably improved performance compared to a reference two-wire antenna. Our work will be useful for the design of high-performance optical antennas and nanoresonators for diverse applications ranging from quantum optics to antenna-enhanced single-emitter spectroscopy and sensing.

  9. Multiband Antennas for SDR Applications

    Directory of Open Access Journals (Sweden)

    E. Surducan

    2009-01-01

    Full Text Available We present multiband antennas configurations for SDR applications. Using a composite folded dipole structure as starting point, we derived more complex antenna configurations to support multiple communication protocols for mobile application with linear and circular polarizations. Prototypes as single antenna with circular polarization, tunable single antenna with PIN diode and MIMO systems with three and four antennas, all derivatives of the same basic structure, were produced in an iterative fashion until the desired parameters were achieved. These antennas are suitable for microstrip circuit realizations and can be included in the printed circuit board (PCB of the device, or used as stand alone. The shapes and measurement results are presented throughout the paper. From the illustrated graphs it can be seen that the stand-alone antennas exhibit positive gain for all the frequency bands of interest while the separation between antennas, for the multiple-input multiple-output (MIMO case, is better than 15 dB.

  10. Hemispheric ultra-wideband antenna.

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert Wesley

    2006-04-01

    This report begins with a review of reduced size ultra-wideband (UWB) antennas and the peculiar problems that arise when building a UWB antenna. It then gives a description of a new type of UWB antenna that resolves these problems. This antenna, dubbed the hemispheric conical antenna, is similar to a conventional conical antenna in that it uses the same inverted conical conductor over a ground plane, but it also uses a hemispheric dielectric fill in between the conductive cone and the ground plane. The dielectric material creates a fundamentally new antenna which is reduced in size and much more rugged than a standard UWB conical antenna. The creation of finite-difference time domain (FDTD) software tools in spherical coordinates, as described in SAND2004-6577, enabled this technological advance.

  11. Galileo satellite antenna modeling

    Science.gov (United States)

    Steigenberger, Peter; Dach, Rolf; Prange, Lars; Montenbruck, Oliver

    2015-04-01

    The space segment of the European satellite navigation system Galileo currently consists of six satellites. Four of them belong to the first generation of In-Orbit Validation (IOV) satellites whereas the other two are Full Operational Capability (FOC) satellites. High-precision geodetic applications require detailed knowledge about the actual phase center of the satellite and receiver antenna. The deviation of this actual phase center from a well-defined reference point is described by phase center offsets (PCOs) and phase center variations (PCVs). Unfortunately, no public information is available about the Galileo satellite antenna PCOs and PCVs, neither for the IOV, nor the FOC satellites. Therefore, conventional values for the IOV satellite antenna PCOs have been adopted for the Multi-GNSS experiment (MGEX) of the International GNSS Service (IGS). The effect of the PCVs is currently neglected and no PCOs for the FOC satellites are available yet. To overcome this deficiency in GNSS observation modeling, satellite antenna PCOs and PCVs are estimated for the Galileo IOV satellites based on global GNSS tracking data of the MGEX network and additional stations of the legacy IGS network. Two completely independent solutions are computed with the Bernese and Napeos software packages. The PCO and PCV values of the individual satellites are analyzed and the availability of two different solutions allows for an accuracy assessment. The FOC satellites are built by a different manufacturer and are also equipped with another type of antenna panel compared to the IOV satellites. Signal transmission of the first FOC satellite has started in December 2014 and activation of the second satellite is expected for early 2015. Based on the available observations PCO estimates and, optionally PCVs of the FOC satellites will be presented as well. Finally, the impact of the new antenna model on the precision and accuracy of the Galileo orbit determination is analyzed.

  12. 7 CFR 1206.21 - Suspend.

    Science.gov (United States)

    2010-01-01

    ... part thereof during a particular period of time specified in the rule. ... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE MANGO PROMOTION, RESEARCH, AND INFORMATION Mango Promotion, Research, and Information Order Definitions § 1206.21 Suspend. Suspend means to...

  13. Wireless Distributed Antenna MIMO

    DEFF Research Database (Denmark)

    2015-01-01

    The present disclosure relates to system applications of multicore optical fibers. One embodiment relates to a base transceiver station for a wireless telecommunication system comprising a plurality of antenna units arranged in a MIMO configuration and adapted for transmission and/or reception...... of radio-frequency signals, an optical transmitter in the form of an electro-optic conversion unit for each of said plurality of antenna units, each electro-optic conversion unit adapted for converting an RF signal into an optical signal, a plurality of a single core optical fibers for guiding the optical...

  14. Printed MIMO antenna engineering

    CERN Document Server

    Sharawi, Mohammad S

    2014-01-01

    Wireless communications has made a huge leap during the past two decades. The multiple-input-multiple-output (MIMO) technology was proposed in the 1990's as a viable solution that can overcome the data rate limit experienced by single-input-single-output (SISO) systems. This resource is focused on printed MIMO antenna system design. Printed antennas are widely used in mobile and handheld terminals due to their conformity with the device, low cost, good integration within the device elements and mechanical parts, as well as ease of fabrication.A perfect design companion for practicing engineers

  15. Antennas on circular cylinders

    DEFF Research Database (Denmark)

    Knudsen, H. L.

    1959-01-01

    antenna in a circular cylinder. By a procedure similar to the one used by Silver and Saunders, expressions have been derived for the field radiated from an arbitrary surface current distribution on a cylinder surface coaxial with a perfectly conducting cylinder. The cases where the space between the two...... cylindrical surfaces have the sane characteristic constants and different constants are treated separately. Extensive numerical computations of the field radiated from the slot antennas described here are being carried out, but no numerical results are yet available...

  16. Antenna (Selected Articles),

    Science.gov (United States)

    1981-11-04

    random layout of the antenna (i.e. ’I=O). It is apparent from the figure that in the region of optimal N, the quantities AN and a2 change slowly. With a...introducing phase distribution of the field along the antenna equal to Z2W we can, in the limits of small angles in the region 0o O0 at distance R0 (focal...Shifrin, Ya. S. "Question of the Effect of Fluctuations on the Diffraction Image of a Focusing System," Trudy ARTA No. 46, 1960. 4. Tatarskiy, V. I. Teoria

  17. Non-standard antennas

    CERN Document Server

    Le Chevalier, Francois; Staraj, Robert

    2013-01-01

    This book aims at describing the wide variety of new technologies and concepts of non-standard antenna systems - reconfigurable, integrated, terahertz, deformable, ultra-wideband, using metamaterials, or MEMS,  etc, and how they open the way to a wide range of applications, from personal security and communications to multifunction radars and towed sonars, or satellite navigation systems, with space-time diversity on transmit and receive. A reference book for designers  in this lively scientific community linking antenna experts and signal processing engineers.

  18. A Reconfigurable Coplanar Waveguide Bowtie Antenna Using an Integrated Ferroelectric Thin-Film Varactor

    Directory of Open Access Journals (Sweden)

    K. C. Pan

    2012-01-01

    Full Text Available A novel printed antenna with a frequency reconfigurable feed network is presented. The antenna consists of a bowtie structure patch radiating element in the inner space of an annulus that is on a nongrounded substrate with a ferroelectric (FE Barium Strontium Titanate (BST thin film. The bowtie patch is fed by a coplanar waveguide (CPW transmission line that also includes a CPW-based BST shunt varactor. Reconfiguration of the compact 8 mm × 8 mm system has been demonstrated by shifting the antenna system’s operating frequency 500 MHz in the 7–9 GHz band by applying a DC voltage bias.

  19. Analysis and design of low profile multiband multifunctional antenna arrays

    Science.gov (United States)

    Hunsicker, Walker F.

    Light-weight phased array antennas for aerospace and mobile applications require utilizing the same antenna aperture to provide multiple functions with dissimilar radiation pattern specifications (e.g., multiband operation for communications and tracking). Multi-functional antennas provide advantages over aggregate antenna clusters by reducing space requirements, and can aid in the optimal placement of all required apertures to provide adequate isolation between channels. Furthermore, the combination of antenna apertures into a common geometry mitigates co-site installation issues by addressing interference within the integrated radiator design itself as opposed to the extensive analysis which is required to configure multiple radiators in close proximity. The combination of multiple radiators into a single aperture can only be achieved with the proper selection of antenna topology and accompanying feed network design. This research proposes a new technique for the design of multiband arrays in which a common aperture is used. Highlighted by this method is the integration of a tri-band array comprised of an X-band (12 GHz) microstrip patch array on a superstrate above printed dual-band (1 and 2 GHz) slot loop antenna arrays in an octave-spaced lattice. The selection of a ground backing reflector is considered for improved gain and system packaging, but restricts the utility of the design principally due to the lambda/4 depth of the ground plane. Therefore, a novel multiband high impedance surfaces (HIS) is proposed to load the slot apertures for reduced height. The novel techniques proposed here will enable the design of a low profile and conformal single aperture supporting multi-band and multi-functional operations.

  20. A Novel Manufacturing Process for Compact, Low-Weight and Flexible Ultra-Wideband Cavity Backed Textile Antennas

    Directory of Open Access Journals (Sweden)

    Dries Van Baelen

    2018-01-01

    Full Text Available A novel manufacturing procedure for the fabrication of ultra-wideband cavity-backed substrate integrated waveguide antennas on textile substrates is proposed. The antenna cavity is constructed using a single laser-cut electrotextile patch, which is folded around the substrate. Electrotextile slabs protruding from the laser-cut patch are then vertically folded and glued to form the antenna cavity instead of rigid metal tubelets to implement the vertical cavity walls. This approach drastically improves mechanical flexibility, decreases the antenna weight to slightly more than 1 g and significantly reduces alignment errors. As a proof of concept, a cavity-backed substrate integrated waveguide antenna is designed and realized for ultra-wideband operation in the [5.15–5.85] GHz band. Antenna performance is validated in free space as well as in two on body measurement scenarios. Furthermore, the antenna’s figures of merit are characterized when the prototype is bent at different curvature radii, as commonly encountered during deployment on the human body. Also the effect of humidity content on antenna performance is studied. In all scenarios, the realized antenna covers the entire operating frequency band, meanwhile retaining a stable radiation pattern with a broadside gain above 5 dBi, and a radiation efficiency of at least 70%.

  1. Slot Parameter Optimization for Multiband Antenna Performance Improvement Using Intelligent Systems

    Directory of Open Access Journals (Sweden)

    Erdem Demircioglu

    2015-01-01

    Full Text Available This paper discusses bandwidth enhancement for multiband microstrip patch antennas (MMPAs using symmetrical rectangular/square slots etched on the patch and the substrate properties. The slot parameters on MMPA are modeled using soft computing technique of artificial neural networks (ANN. To achieve the best ANN performance, Particle Swarm Optimization (PSO and Differential Evolution (DE are applied with ANN’s conventional training algorithm in optimization of the modeling performance. In this study, the slot parameters are assumed as slot distance to the radiating patch edge, slot width, and length. Bandwidth enhancement is applied to a formerly designed MMPA fed by a microstrip transmission line attached to the center pin of 50 ohm SMA connecter. The simulated antennas are fabricated and measured. Measurement results are utilized for training the artificial intelligence models. The ANN provides 98% model accuracy for rectangular slots and 97% for square slots; however, ANFIS offer 90% accuracy with lack of resonance frequency tracking.

  2. Wireless communication with multiple antennas

    Indian Academy of Sciences (India)

    admin

    Wireless communications has seen a very rapid growth, both in practice and theory, during the past one decade. Most of the present wireless communication systems use one transmit antenna and one receive antenna. However, communication with multiple transmit and multiple receive antennas can enormously increase ...

  3. Adhesive RFID Sensor Patch for Monitoring of Sweat Electrolytes.

    Science.gov (United States)

    Rose, Daniel P; Ratterman, Michael E; Griffin, Daniel K; Hou, Linlin; Kelley-Loughnane, Nancy; Naik, Rajesh R; Hagen, Joshua A; Papautsky, Ian; Heikenfeld, Jason C

    2015-06-01

    Wearable digital health devices are dominantly found in rigid form factors such as bracelets and pucks. An adhesive radio-frequency identification (RFID) sensor bandage (patch) is reported, which can be made completely intimate with human skin, a distinct advantage for chronological monitoring of biomarkers in sweat. In this demonstration, a commercial RFID chip is adapted with minimum components to allow potentiometric sensing of solutes in sweat, and surface temperature, as read by an Android smartphone app with 96% accuracy at 50 mM Na(+) (in vitro tests). All circuitry is solder-reflow integrated on a standard Cu/polyimide flexible-electronic layer including an antenna, but while also allowing electroplating for simple integration of exotic metals for sensing electrodes. Optional paper microfluidics wick sweat from a sweat porous adhesive allowing flow to the sensor, or the sensor can be directly contacted to the skin. The wearability of the patch has been demonstrated for up to seven days, and includes a protective textile which provides a feel and appearance similar to a standard Band-Aid. Applications include hydration monitoring, but the basic capability is extendable to other mM ionic solutes in sweat (Cl(-), K(+), Mg(2+), NH4(+), and Zn(2+)). The design and fabrication of the patch are provided in full detail, as the basic components could be useful in the design of other wearable sensors.

  4. Analysis of High Tc Superconducting Rectangular Microstrip Patches over Ground Planes with Rectangular Apertures in Substrates Containing Anisotropic Materials

    Directory of Open Access Journals (Sweden)

    Abderraouf Messai

    2013-01-01

    Full Text Available A rigorous full-wave analysis of high Tc superconducting rectangular microstrip patch over ground plane with rectangular aperture in the case where the patch is printed on a uniaxially anisotropic substrate material is presented. The dyadic Green’s functions of the considered structure are efficiently determined in the vector Fourier transform domain. The effect of the superconductivity of the patch is taken into account using the concept of the complex resistive boundary condition. The accuracy of the analysis is tested by comparing the computed results with measurements and previously published data for several anisotropic substrate materials. Numerical results showing variation of the resonant frequency and the quality factor of the superconducting antenna with regard to operating temperature are given. Finally, the effects of uniaxial anisotropy in the substrate on the resonant frequencies of different TM modes of the superconducting microstrip antenna with rectangular aperture in the ground plane are presented.

  5. Low-profile Circularly Polarized Antenna Exploiting Fabry-Perot Resonator Principle

    Directory of Open Access Journals (Sweden)

    K. Pitra

    2015-12-01

    Full Text Available We designed a patch antenna surrounded by a mushroom-like electromagnetic band-gap (EBG structure and completed it by a partially reflective surface (PRS. EBG suppresses surface waves and creates the bottom wall of the Fabry-Perot (FP resonator. PRS plays the role of a planar lens and forms the top wall of the FP resonator. The novel PRS consists of a two-layer grid exhibiting inductive and capacitive (LC behavior which allows us to obtain a reflection phase between –108 and +180 degrees. Thanks to this PRS, we can control the height of the cavity in the range from lambda/2 to lambda/300. Obtained results show that the FP resonator antenna enables us to achieve a low profile and a high-gain. The patch is excited by a microstrip transmission line via the cross-slot aperture generating the circular polarization. Functionality of the described concept of the FP antenna was verified at 10 GHz. The antenna gain was 15 dBi, the impedance bandwidth 2.3% for |S11| less than –10 dB, and the axial ratio bandwidth 0.6% for AR less than 3.0 dB. Hence, the antenna is suitable for narrowband applications. Computer simulations show that the microwave FP antenna can be simply redesigned to serve as a source of circularly polarized terahertz waves.

  6. Novel High-Gain Circularly Polarized Lens Antenna Using Single-Layer Transmissive Metasurface

    Science.gov (United States)

    Zhuang, Yaqiang; Wang, Guangming; Li, Haipeng; Guo, Wenlong

    2017-05-01

    A high-gain lens antenna employing single-layer focusing metasurface (MS) is proposed in this article. The single-layer element achieves a 360° transmission phase range with a transmission magnitude better than 0.9. And the focusing MS consists of 169 elements was designed by utilizing the technique of varying rotation angle to compensate the phase delay. Thus, a lens antenna is constructed by placing a circularly polarized (CP) patch antenna at the focal point of the MS. The fabricated lens antenna demonstrates a good performance of 4.6 % 3-dB axial ratio bandwidth and 6 % 1-dB gain bandwidth, respectively. Moreover, the maximum gain is 18.3 dBic at 15 GHz, which is enhanced by 11.4 dBic compared with the patch antenna. Due to the single-layer structure, this design has a low profile and easy fabrication process compared with the conventional designs, making it an attractive alternative to compact high-gain antenna.

  7. Validation of Emulated Omnidirectional Antenna Output Using Directive Antenna Data

    DEFF Research Database (Denmark)

    Hejselbæk, Johannes; Karstensen, Anders; Nielsen, Jesper Ødum

    2017-01-01

    In this paper, we present validation of a method for constructing a virtual omnidirectional antenna in the azimuth plane. The virtual omnidirectional antenna utilizes a combination of data from directive horn antennas. The aim is to utilize the high gain of the horn antenna to improve the dynamic...... range of channel sounding measurements conducted in the centimeter and millimeter wave bands. The resulting complex impulse response from the virtual omnidirectional antenna is used to find the power-delay-profile (PDP). This is then compared to measurements conducted at the same time using a real...... omnidirectional antenna. The validation shows that the synthesized omnidirectional is capable of predicting main components and the slope of the PDP. Further, it is shown that by choosing angular sampling steps corresponding to the half power beam width (HPBW) of the used antenna similar power levels can...

  8. Antenna feeds and receivers

    Science.gov (United States)

    Mccall, B.

    1972-01-01

    The results of 7 months of study, tradeoffs, test design, and fabrication are presented for an effort to modify three ground stations in support of the ATS-F program. As a result of tests on the existing feed system of the Rosman No. 2 85-foot antenna and on the transportable ground station (TGS) 40-foot antenna, it was determined that modifications of the existing phase-compensating rotary joints at Rosman are feasible. Other components must be completely replaced. In the TGS antenna feed system, it was found to be feasible to broadband the existing monopulse comparator by adding simple irises and posts; both spare and active comparators were modified. The TGS polarizers can be broadbanded by adjusting existing pins and adding two new pins. These modifications are also directly applicable to the Mojave 40-foot antenna. Detailed electrical and mechanical characteristics are presented for the new equipment, as well as installation plans to enable NASA and its contractors to determine the adequacy of the designs and to confirm that planned locations are both available and compatible with planned operational concepts.

  9. Frequency scanning microstrip antennas

    DEFF Research Database (Denmark)

    Danielsen, Magnus; Jørgensen, Rolf

    1979-01-01

    The principles of using radiating microstrip resonators as elements in a frequency scanning antenna array are described. The resonators are cascade-coupled. This gives a scan of the main lobe due to the phase-shift in the resonator in addition to that created by the transmission line phase...

  10. Biconical receiving antenna

    Science.gov (United States)

    Grimes, Dale M.

    1982-05-01

    The modal solution to a biconical receiving antenna with arbitrary arm angles and lengths is presented in the form of sums over special functions; sums which are exact in the sense that no electromagnetic approximations are made. The antenna load is confined within a sphere of small radius centered at the apices of the cones. The analytical formulation is presented, along with solutions for ψ very small and very large, and certain selected numerical data. The general solution permits calculation of all detailed fields near and far, both receiving and transmitting current modes on the antenna arms and caps and the power and the momentum absorbed by the antenna from an incoming plane wave. It is shown that the receiving current modes are necessary for electromagnetic momentum to be conserved during power reception. Detailed calculation of comparative receiving and transmitting admittances confirms that they are identical, as predicted by the reciprocity theorem. The radiation patterns, however, for retransmission during reception and for transmission differ.

  11. A Compact Dual-Band RFID Tag Antenna Mountable on Metallic Objects

    Directory of Open Access Journals (Sweden)

    Byeonggwi Mun

    2015-01-01

    Full Text Available A compact (50 × 50 × 4 mm3 dual-band radio frequency identification (RFID tag antenna mountable on metallic objects is proposed for the ultra-high frequency (UHF band (917∼923.5 MHz and the microwave (MW band (2.4∼2.45 GHz. With the proximity-coupled feed loop, the proposed antenna consists of two symmetric planar inverted-F antenna (PIFA elements for the UHF band passive tag and a meander microstrip patch antenna for the MW band active tag. The performance of the proposed antenna is verified by mounting it on the different sizes of the metallic object. Furthermore, the passive tag antenna in the UHF band furthermore may be used for energy harvesting techniques to improve the lifetime of the active tag in the MW band. The measured maximum read range is 5.50 m in the UHF band and 14.15 m in the MW band when the proposed tag antenna is mounted on the metallic objects. The total efficiency for all operating frequency bands is higher than 50%. High isolation (>12 dB between tag antennas in the UHF band and the MW band is achieved.

  12. High Gain and High Directive of Antenna Arrays Utilizing Dielectric Layer on Bismuth Titanate Ceramics

    Directory of Open Access Journals (Sweden)

    F. H. Wee

    2012-01-01

    Full Text Available A high gain and high directive microstrip patch array antenna formed from dielectric layer stacked on bismuth titanate (BiT ceramics have been investigated, fabricated, and measured. The antennas are designed and constructed with a combination of two-, four-, and six-BiT elements in an array form application on microwave substrate. For gain and directivity enhancement, a layer of dielectric was stacked on the BiT antenna array. We measured the gain and directivity of BiT array antennas with and without the dielectric layer and found that the gain of BiT array antenna with the dielectric layer was enhanced by about 1.4 dBi of directivity and 1.3 dB of gain over the one without the dielectric layer at 2.3 GHz. The impedance bandwidth of the BiT array antenna both with and without the dielectric layer is about 500 MHz and 350 MHz, respectively, which is suitable for the application of the WiMAX 2.3 GHz system. The utilization of BiT ceramics that covers about 90% of antenna led to high radiation efficiency, and small-size antennas were produced. In order to validate the proposed design, theoretical and measured results are provided and discussed.

  13. *NEW* CRITICAL Windows Security patches

    CERN Multimedia

    2003-01-01

    On 3 October and 10 September 2003, Microsoft issued new CRITICAL security patches MS03-040 and MS03-039. They must be URGENTLY applied on ALL WINDOWS systems, which are not centrally managed for security patches. This includes Experiment computers, Home computers and Windows Portable and Desktop systems not running NICE. Details of the security holes and patches are at: MS03-039: http://cern.ch/it-div/news/hotfix-MS03-039.asp http://www.microsoft.com/technet/security/bulletin/MS03-039.asp MS03-040: http://cern.ch/it-div/news/hotfix-MS03-040.asp http://www.microsoft.com/technet/security/bulletin/MS03-040.asp

  14. Micromachined patch-clamp apparatus

    Science.gov (United States)

    Okandan, Murat

    2012-12-04

    A micromachined patch-clamp apparatus is disclosed for holding one or more cells and providing electrical, chemical, or mechanical stimulation to the cells during analysis with the patch-clamp technique for studying ion channels in cell membranes. The apparatus formed on a silicon substrate utilizes a lower chamber formed from silicon nitride using surface micromachining and an upper chamber formed from a molded polymer material. An opening in a common wall between the chambers is used to trap and hold a cell for analysis using the patch-clamp technique with sensing electrodes on each side of the cell. Some embodiments of the present invention utilize one or more electrostatic actuators formed on the substrate to provide mechanical stimulation to the cell being analyzed, or to provide information about mechanical movement of the cell in response to electrical or chemical stimulation.

  15. Antenna theory analysis and design

    CERN Document Server

    Balanis, Constantine A

    2005-01-01

    The discipline of antenna theory has experienced vast technological changes. In response, Constantine Balanis has updated his classic text, Antenna Theory, offering the most recent look at all the necessary topics. New material includes smart antennas and fractal antennas, along with the latest applications in wireless communications. Multimedia material on an accompanying CD presents PowerPoint viewgraphs of lecture notes, interactive review questions, Java animations and applets, and MATLAB features. Like the previous editions, Antenna Theory, Third Edition meets the needs of e

  16. Terminal Antennas in ACE2

    Directory of Open Access Journals (Sweden)

    M. Martinez-Vazquez

    2008-06-01

    Full Text Available The ACE Network of Excellence was a European Commission funded Network of Excellence, which lasted from 2004 to 2007. One of the activities performed by this Network was in the frame of terminal antennas. In this activity, three aspects were covered in three projects: Small antenna technologies, small terminal antenna technologies and benchmarking of small terminal antennas measurement facilities. The overall aim was to identify the newest trends in antenna design and measurement for personal communications devices, and suggest novel solutions and design methodologies for various applications. The results of this work are presented in this paper.

  17. Quartz antenna with hollow conductor

    Science.gov (United States)

    Leung, Ka-Ngo; Benabou, Elie

    2002-01-01

    A radio frequency (RF) antenna for plasma ion sources is formed of a hollow metal conductor tube disposed within a glass tube. The hollow metal tubular conductor has an internal flow channel so that there will be no coolant leakage if the outer glass tube of the antenna breaks. A portion of the RF antenna is formed into a coil; the antenna is used for inductively coupling RF power to a plasma in an ion source chamber. The antenna is made by first inserting the metal tube inside the glass tube, and then forming the glass/metal composite tube into the desired coil shape.

  18. Electromagnetic reciprocity in antenna theory

    CERN Document Server

    Stumpf, Martin

    2018-01-01

    The reciprocity theorem is among the most intriguing concepts in wave field theory and has become an integral part of almost all standard textbooks on electromagnetic (EM) theory. This book makes use of the theorem to quantitatively describe EM interactions concerning general multiport antenna systems. It covers a general reciprocity-based description of antenna systems, their EM scattering properties, and further related aspects. Beginning with an introduction to the subject, Electromagnetic Reciprocity in Antenna Theory provides readers first with the basic prerequisites before offering coverage of the equivalent multiport circuit antenna representations, EM coupling between multiport antenna systems and their EM interactions with scatterers, accompanied with the corresponding EM compensation theorems.

  19. Design and Development of Aerogel-Based Antennas for Aerospace Applications: A Final Report to the NARI Seedling

    Science.gov (United States)

    Meador, Mary Ann B.; Miranda, Felix A.

    2014-01-01

    As highly porous solids possessing low density and low dielectric permittivity combined with good mechanical properties, polyimide (PI) aerogels offer great promise as an enabling technology for lightweight aircraft antenna systems. While they have been aggressively explored for thermal insulation, barely any effort has been made to leverage these materials for antennas or other applications that take advantage of their aforementioned attributes. In Phase I of the NARI Seedling Project, we fabricated PI aerogels with properties tailored to enable new antenna concepts with performance characteristics (wide bandwidth and high gain) and material properties (low density, environmental stability, and robustness) superior to the state of practice (SOP). We characterized electromagnetic properties, including permittivity, reflectivity, and propagation losses for the aerogels. Simple, prototype planar printed circuit patch antennas from down-selected aerogel formulations were fabricated by molding the aerogels to net shapes and by gold-metalizing the pattern onto the templates via electron beam evaporation in a clean room environment. These aerogel based antennas were benchmarked against current antenna SOP, and exhibited both broader bandwidth and comparable or higher gain performance at appreciably lower mass. Phase II focused on the success of the Phase I results pushing the PI aerogel based antenna technology further by exploring alternative antenna design (i.e., slot coupled antennas) and by examining other techniques for fabricating the antennas including ink jet printing with the goal of optimizing antenna performance and simplifying production. We also examined new aerogel formulations with better moisture and solvent resistance to survive processing conditions. In addition, we investigated more complex antenna designs including passive phased arrays such as 2x4 and 4x8 element arrays to assess the scalability of the aerogel antenna concept. Furthermore, we

  20. Shape Analysis and Deployment of the ExaVolt Antenna

    Science.gov (United States)

    Baginski, Frank; Zhao, Kaiyu; Furer, Joshua; Landay, Justin; Bailoor, Shantanu; Gorham, Peter; Varner, Gary; Miki, Christian; Hill, Brian; Schoorlemmer, Harm; Nguyen, Liem; Romero-Wolf, Andrew; Liewer, Kurt; Sauder, Jonathan; Brakke, Kenneth; Beatty, Jim; Connolly, Amy; Allison, Patrick; Pfendner, Carl; Dailey, Brian; Fairbrother, Debra; Said, Magdi; Lang, Steven; Young, Leyland

    The ExaVolt Antenna (EVA) is the next generation balloon-borne ultra-high energy (UHE) particle observatory under development for NASA’s suborbital super-pressure balloon program in Antarctica. Unlike a typical mission where the balloon lifts a gondola that carries the primary scientific instrument, the EVA mission is a first-of-its-kind in that the balloon itself is part of the science instrument. Specifically, a toroidal RF reflector is mounted onto the outside surface of a superpressure balloon (SPB) and a feed antenna is suspended inside the balloon, creating a high-gain antenna system with a synoptic view of the Antarctic ice sheet. The EVA mission presents a number of technical challenges. For example, can a stowed feed antenna be inserted through an opening in the top-plate? Can the feed antenna be deployed during the ascent? Once float altitude is achieved, how might small shape changes in the balloon shape affect the antenna performance over the life of the EVA mission? The EVA team utilized a combination of testing with a 1/20-scale physical model, mathematical modeling and numerical simulations to probe these and related questions. While the problems are challenging, they are solvable with current technology and expertise. Experiments with a 1/20-scale EVA physical model outline a pathway for inserting a stowed feed into a SPB. Analysis indicates the EVA system will ascend, deploy and assume a stable configuration at float altitude. Nominal shape changes in an Antarctic SPB are sufficiently small to allow the use of the surface of the balloon as a high-gain reflector.

  1. A Switchable 3D-Coverage Phased Array Antenna Package for 5G Mobile Terminals

    DEFF Research Database (Denmark)

    Ojaroudiparchin, Naser; Shen, Ming; Zhang, Shuai

    2016-01-01

    This manuscript proposes a new design of a millimeter-wave (mm-Wave) array antenna package with beam steering characteristic for the fifth generation (5G) mobile applications. In order to achieve a broad 3D scanning coverage of the space with high-gain beams, three identical sub arrays of patch...... antennas have been compactly arranged along the edge region of the mobile phone PCB to form the antenna package. By switching the feeding to one of the sub arrays, the desired direction of coverage can be achieved. The proposed design has >10 dB gain in the upper spherical space, good directivity...... and efficiency, which is suitable for 5G mobile communications. In addition, the impact of user’s hand on the antenna performance has been investigated....

  2. Bandwidth Extension of a Printed Square Monopole Antenna Loaded with Periodic Parallel-Plate Lines

    Directory of Open Access Journals (Sweden)

    Linglong Meng

    2017-01-01

    Full Text Available A novel wideband monopole antenna employing periodically loaded parallel-plate lines is presented in this paper. The proposed antenna consists of a main square patch, a rectangular ground plane, and a periodical structure which is printed on both sides of substrate. A strong electromagnetic coupling technique is used to design the element that enhances impedance bandwidth and decreases the side-lobe level throughout the effective bandwidth. The antenna achieves a wide impedance bandwidth of about 61.1% or ranging from 2.16 to 4.06 GHz, an omnidirectional far-field pattern, and a peak radiation gain of 2.37 dBi. Finally, the proposed antenna is analyzed and measured. The measured results show satisfactory performance and good agreement with the simulated results.

  3. Circularly Polarized Antenna Array Fed by Air-Bridge Free CPW-Slotline Network

    Directory of Open Access Journals (Sweden)

    Yilin Liu

    2017-01-01

    Full Text Available A novel design of 1×2 and 2×2 circularly polarized (CP microstrip patch antenna arrays is presented in this paper. The two CP antenna arrays are fed by sequentially rotated coplanar waveguide (CPW to slotline networks and are processed on 1 mm thick single-layer FR4 substrates. Both of the two arrays are low-profile and lightweight. An air-bridge free CPW-slotline power splitter is appropriately designed to form the feeding networks and realize the two CP antenna arrays. The mechanism of circular polarization in this design is explained. The simulated and measured impedance bandwidths as well as the 3 dB axial ratio bandwidths and the radiation patterns of the two proposed antenna arrays are presented. This proposed design can be easily extended to form a larger plane array with good performance owing to its simple structure.

  4. X-band printed phased array antennas using high-performance CNT/ion gel/Ag transistors

    Science.gov (United States)

    Grubb, Peter M.; Bidoky, Fazel; Mahajan, Ankit; Subbaraman, Harish; Li, Wentao; Frisbie, Daniel; Chen, Ray T.

    2016-05-01

    This paper reports a fully printed phased array antenna developed on a 125 micron thick flexible Kapton substrate. Switching for the phase delay lines is accomplished using printed carbon nanotube transistors with ion gel dielectric layers. Design of each element of the phased array antenna is reported, including a low loss constant impedance power divider, a phase shifter network, and patch antenna design. Steering of an X-band PAA operating at 10GHz from 0 degrees to 22.15 degrees is experimentally demonstrated. In order to completely package the array with electrical interconnects, a single substrate interconnect scheme is also investigated.

  5. Design of a New Built-in UHF Multi-Frequency Antenna Sensor for Partial Discharge Detection in High-Voltage Switchgears

    Directory of Open Access Journals (Sweden)

    Xiaoxing Zhang

    2016-07-01

    Full Text Available In this study a new built-in ultrahigh frequency (UHF antenna sensor was designed and applied in a high-voltage switchgear for partial discharge (PD detection. The casing of the switchgear was initially used as the ground plane of the antenna sensor, which integrated the sensor into the high-voltage switchgear. The Koch snowflake patch was adopted as the radiation patch of the antenna to overcome the disadvantages of common microstrip antennas, and the feed position and the dielectric layer thickness were simulated in detail. Simulation results show that the antenna sensor possessed four resonant points with good impedance matching from 300 MHz to 1000 MHz, and it also presented good multi-frequency performance in the entire working frequency band. PD detection experiments were conducted in the high-voltage switchgear, and the fabricated antenna sensor was effectively built into the high-voltage switchgear. In order to reflect the advantages of the built-in antenna sensor, another external UHF antenna sensor was used as a comparison to simultaneously detect PD. Experimental results demonstrated that the built-in antenna sensor possessed high detection sensitivity and strong anti-interference capacity, which ensured the practicability of the design. In addition, it had more high-voltage switchgear PD detection advantages than the external sensor.

  6. Compact printed multiband antenna with independent setting suitable for fixed and reconfigurable wireless communication systems

    KAUST Repository

    Abutarboush, Hattan

    2012-08-01

    This paper presents the design of a low-profile compact printed antenna for fixed frequency and reconfigurable frequency bands. The antenna consists of a main patch, four sub-patches, and a ground plane to generate five frequency bands, at 0.92, 1.73, 1.98, 2.4, and 2.9 GHz, for different wireless systems. For the fixed-frequency design, the five individual frequency bands can be adjusted and set independently over the wide ranges of 18.78%, 22.75%, 4.51%, 11%, and 8.21%, respectively, using just one parameter of the antenna. By putting a varactor (diode) at each of the sub-patch inputs, four of the frequency bands can be controlled independently over wide ranges and the antenna has a reconfigurable design. The tunability ranges for the four bands of 0.92, 1.73, 1.98, and 2.9 GHz are 23.5%, 10.30%, 13.5%, and 3%, respectively. The fixed and reconfigurable designs are studied using computer simulation. For verification of simulation results, the two designs are fabricated and the prototypes are measured. The results show a good agreement between simulated and measured results. © 1963-2012 IEEE.

  7. Rippling instabilities in suspended nanoribbons

    Science.gov (United States)

    Wang, Hailong; Upmanyu, Moneesh

    2012-11-01

    Morphology mediates the interplay between the structure and electronic transport in atomically thin nanoribbons such as graphene as the relaxation of edge stresses occurs preferentially via out-of-plane deflections. In the case of end-supported suspended nanoribbons that we study here, past experiments and computations have identified a range of equilibrium morphologies, in particular, for graphene flakes, yet a unified understanding of their relative stability remains elusive. Here, we employ atomic-scale simulations and a composite framework based on isotropic elastic plate theory to chart out the morphological stability space of suspended nanoribbons with respect to intrinsic (ribbon elasticity) and engineered (ribbon geometry) parameters, and the combination of edge and body actuation. The computations highlight a rich morphological shape space that can be naturally classified into two competing shapes, bendinglike and twistlike, depending on the distribution of ripples across the interacting edges. The linearized elastic framework yields exact solutions for these rippled shapes. For compressive edge stresses, the body strain emerges as a key variable that controls their relative stability and in extreme cases stabilizes coexisting transverse ripples. Tensile edge stresses lead to dimples within the ribbon core that decay into the edges, a feature of obvious significance for stretchable nanoelectronics. The interplay between geometry and mechanics that we report should serve as a key input for quantifying the transport along these ribbons.

  8. Fentanyl Patch Can Be Deadly to Children

    Science.gov (United States)

    ... Products For Consumers Home For Consumers Consumer Updates Fentanyl Patch Can Be Deadly to Children Share Tweet ... from accidental exposure to a skin patch containing fentanyl, a powerful pain reliever. As a result of ...

  9. Bye-Bye Flu Shot, Hello Patch?

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_166897.html Bye-Bye Flu Shot, Hello Patch? Early results look promising for ... TUESDAY, June 27, 2017 (HealthDay News) -- An experimental flu vaccine patch with dissolving microneedles appears safe and ...

  10. Evaluation of concrete pavement patching techniques.

    Science.gov (United States)

    1989-01-01

    This final report presents the results of a study undertaken to improve in concrete pavement patching techniques. Activities included an evaluation of the suitability of the impact hammer and maturity calculations for determining when a patch is read...

  11. Low Profile Antenna Performance Study Part 2. Broadband Antenna Techniques Survey

    Science.gov (United States)

    1977-10-01

    shaped radiators, presented in the literature [141, [15], and depicted in Figs. 3b and c, resemble the biconical antenna and Alford’s tapered-horn...V Research and Development Technical Report .ECOM-4542 LOW PROFILE ANTENNA PERFORMANCE STUDY PART I1: BROADBAND ANTENNA TECHNIQUES SURVEY C. M...Small antenna , low-profile antenna , broadband matching, folded antennas , multi- element antennas , antenna loading. 90. ABSTRACT (Conlinu en revere, side

  12. Stretchable antenna for wearable electronics

    KAUST Repository

    Hussain, Muhammad Mustafa

    2017-04-13

    Various examples are provided for stretchable antennas that can be used for applications such as wearable electronics. In one example, a stretchable antenna includes a flexible support structure including a lateral spring section having a proximal end and at a distal end; a metallic antenna disposed on at least a portion of the lateral spring section, the metallic antenna extending along the lateral spring section from the proximal end; and a metallic feed coupled to the metallic antenna at the proximal end of the lateral spring section. In another example, a method includes patterning a polymer layer disposed on a substrate to define a lateral spring section; disposing a metal layer on at least a portion of the lateral spring section, the metal layer forming an antenna extending along the portion of the lateral spring section; and releasing the polymer layer and the metal layer from the substrate.

  13. Miniaturization of Spherical Magnetodielectric Antennas

    DEFF Research Database (Denmark)

    Hansen, Troels Vejle

    The fundamental limitations in performance of electrically small antennas (ESAs) - and how far these may be approached - have been of great interest for over a century. Particularly over the past few decades, it has become increasingly relevant and important, to approach these limits in view...... to the important antenna parameters of radiation efficiency e and impedance bandwidth. For single-mode antennas the fundamental minimum Q is the Chu lower bound. In this Ph.D. dissertation, the topic is miniaturization of spherical antennas loaded by an internal magnetodielectric core. The goal is to determine......, quantify, and assess the effects of an internal material loading upon antenna performance, including its potentials towards miniaturization. Emphasis have been upon performing an exhaustive and exact analysis of rigorous validity covering a large class of spherical antennas. In the context of this study...

  14. A Compact UWB Diversity Antenna

    Directory of Open Access Journals (Sweden)

    Hui Zhao

    2014-01-01

    Full Text Available A compact printed ultrawideband (UWB diversity antenna with a size of 30 mm × 36 mm operating at a frequency range of 3.1–10.6 GHz is proposed. The antenna is composed of two semielliptical monopoles fed by two microstrip lines. Two semicircular slots, two rectangular slots, and one stub are introduced in the ground plane to adjust the impedance bandwidth of the antenna and improve the isolation between two feeding ports. The simulated and measured results show that impedance bandwidth of the proposed antenna can cover the whole UWB band with a good isolation of < −15 dB. The radiation patterns, peak antenna gain, and envelope correlation coefficient are also measured and discussed. The measured results show that the proposed antenna can be a good candidate for some portable MIMO/diversity UWB applications.

  15. Antenna Calibration and Measurement Equipment

    Science.gov (United States)

    Rochblatt, David J.; Cortes, Manuel Vazquez

    2012-01-01

    A document describes the Antenna Calibration & Measurement Equipment (ACME) system that will provide the Deep Space Network (DSN) with instrumentation enabling a trained RF engineer at each complex to perform antenna calibration measurements and to generate antenna calibration data. This data includes continuous-scan auto-bore-based data acquisition with all-sky data gathering in support of 4th order pointing model generation requirements. Other data includes antenna subreflector focus, system noise temperature and tipping curves, antenna efficiency, reports system linearity, and instrument calibration. The ACME system design is based on the on-the-fly (OTF) mapping technique and architecture. ACME has contributed to the improved RF performance of the DSN by approximately a factor of two. It improved the pointing performances of the DSN antennas and productivity of its personnel and calibration engineers.

  16. Near Field Antenna Measurement System.

    Science.gov (United States)

    1978-01-11

    provided which , while designed pr imar ily to support the AN/ TPQ-36 and AN/TPQ-37 antenna s, can readily be used with other antennas. This antenna...tJ~~ ct .nt.r. d In Block 20, Ii dill spans from Raport) Same 13. S U P P L E M E N T A R Y N OT E S None 19. KEY WORDS (Conti nua on revere, side if

  17. Diagnostic patch test concentration for Kathon CG.

    Science.gov (United States)

    Maibach, H I

    1985-10-01

    Patch test studies, 21-day cumulative irritancy assays and Draize repeat insult patch tests with Kathon CG, were used to ascertain an appropriate diagnostic patch test concentration. A dilution of 100 ppm a.i. (aq. or pet.) appears to have low irritancy potential. Further observations are required to verify if this concentration is high enough to detect most cases of sensitization.

  18. Assessment of the effectiveness of nontransdermal energy patches on muscle endurance and power.

    Science.gov (United States)

    Jacobson, Bert H; Smith, Doug B; Stemm, John D; Warren, Aric J; O'Brien, Matt S; Glass, Rob G

    2008-05-01

    Claims of recently developed energy patches suggest that organic nanoscale biomolecular "antennas" produced by L and D-stereoisomers resonate at frequencies in unison with molecules in the cells inducing electron flow to assists in recruiting calcium ions, allowing greater muscle fiber recruitment during muscle contraction. The purpose of the study was to assess the efficacy of energy patches in the performance of selected muscle power and endurance measures. After a 5-minute warm-up and stretch, 41 college varsity football players (age, 20.37 +/- 1.24 years; height, 169.91 +/- 7.44 cm; weight, 109.45 +/- 19.85 kg) were pre-tested on 102-kg maximal bench press repetitions, standing vertical jump, grip strength, peak torque, torque to body weight, total work, average power, and average torque as measured by 50 repetitions of leg extensions at 180 degrees .s. The following week, the players were randomly assigned the experimental or placebo patches. After placement of the patches, the participants again completed a 5-minute warm-up, followed by the identical pre-test protocol. Repeated-measures ANOVAs were used to compare resultant data. No significant group interaction effects were found between experimental and placebo patches for maximal bench press repetitions (p = 0.48), vertical jump distance (p = 0.39), grip strength (p = 0.29), total work (p = 0.26), torque to body weight (p = 0.05), average peak torque (p = 0.08), and average power (p = 0.05). A significant increase occurred in the experimental group for peak torque (p = 0.04). It was concluded that the energy patches significantly improved performance over placebo patches in one of the eight variables tested and registered near significance in two additional variables. However, inconsistency in overall results demands further studies to determine the reliability in improvement of performance in the presence of energy patches.

  19. Design of a wide-gain-bandwidth metasurface antenna at terahertz frequency

    Science.gov (United States)

    Hussain, Niamat; Park, Ikmo

    2017-05-01

    This paper presents the design of a planar low-profile, wide-gain-bandwidth metasurface antenna at terahertz frequency. The proposed antenna consists of a metasurface and a planar feeding structure, both of which are patterned on an electrically thin, high-permittivity GaAs substrate. The metasurface, which is printed on the top of the substrate, consists of a periodic array of 5×5 square patches, while the planar feeding structure, which is printed on the bottom of the substrate, is a wideband, leaky-wave, open-ended slotline, which is fed at the center. The antenna with a single feeding structure showed a maximum broadside gain of 9.8 dBi, a radiation efficiency of 69%, and a 3-dB gain bandwidth of 16% (0.34-0.4 THz). The antenna gain performance was significantly improved by exciting the antenna with an array of slit feeding and without changing the antenna size. The antenna with a multiple (five) feeding structure showed a gain of 15.5 dBi, a 3-dB gain bandwidth of 17.3%, and a radiation efficiency of 73%. This antenna achieved a size reduction of 31 times in terms of device thickness in comparison with the design of the lens coupled antenna while achieving a comparable gain. In addition to its high gain and wide-gain-bandwidth characteristics, the proposed antenna design exhibits a low-profile mechanical robustness, easy integration into circuit boards, and excellent low-cost mass production suitability.

  20. Simple Mu-Negative Half Mode CRLH Antenna Configuration for MIMO Applications

    Directory of Open Access Journals (Sweden)

    M. A. Abdalla

    2017-04-01

    Full Text Available A design of compact size mu-negative half mode composite right left handed metamaterial antenna, using only series capacitive loading, for MIMO application is presented. The proposed configuration is simple as it is realized using via free configuration. The MIMO antenna is formed using two antenna elements designed to operate at 5.8 GHz for wireless applications. The overall MIMO antenna size is only 2.6 × 2.6 cm^2 with in-between separation = 1.8 mm (0.034 lambda_0. Moreover, the ports mutual coupling reduction between the two antenna elements, achieved without using extra structure, is lower than -20 dB. Compared to conventional two microstrip patch MIMO antennas, our proposed configuration has more than 50 % size reduction and 9 dB enhancement in the mutual coupling for the same separation. The antenna design principles, full wave simulations, experimental measurements are introduced with good agreement. Finally, the MIMO parameters are extracted and discussed.

  1. Antenna arrays a computational approach

    CERN Document Server

    Haupt, Randy L

    2010-01-01

    This book covers a wide range of antenna array topics that are becoming increasingly important in wireless applications, particularly in design and computer modeling. Signal processing and numerical modeling algorithms are explored, and MATLAB computer codes are provided for many of the design examples. Pictures of antenna arrays and components provided by industry and government sources are presented with explanations of how they work. Antenna Arrays is a valuable reference for practicing engineers and scientists in wireless communications, radar, and remote sensing, and an excellent textbook for advanced antenna courses.

  2. Wearable Quarter-Wave Folded Microstrip Antenna for Passive UHF RFID Applications

    Directory of Open Access Journals (Sweden)

    Thomas Kaufmann

    2013-01-01

    Full Text Available A wearable low-profile inset-fed quarter-wave folded microstrip patch antenna for noninvasive activity monitoring of elderly is presented. The proposed antenna is embedded with a sensor-enabled passive radio-frequency identification (RFID tag operating in the ultra-high frequency (UHF industrial-scientific-medical (ISM band around 900 MHz. The device exhibits a low and narrow profile based on a planar folded quarter-wave length patch structure and is integrated on a flexible substrate to maximise comfort to the wearer. An extended ground plane made from silver fabric successfully minimises the impact of the human body on the antenna performance. Measurements on a prototype demonstrate a reflection coefficient (S11 of −30 dB at resonance and a −10 dB bandwidth from 920 MHz to 926 MHz. Simulation results predict a maximum gain of 2.8 dBi. This is confirmed by tag measurements where a 4-meter read range is achieved using a transmit power of 30 dBm, for the case where the passive wearable tag antenna is mounted on a body in a practical setting. This represents an almost 40% increase in read range over an existing dipole antenna placed over a 10 mm isolator layer on a human subject.

  3. Optically Controlled Reconfigurable Antenna Array Based on E-Shaped Elements

    Directory of Open Access Journals (Sweden)

    Arismar Cerqueira Sodré Junior

    2014-01-01

    Full Text Available This work presents the development of optically controlled reconfigurable antenna arrays. They are based on two patch elements with E-shaped slots, a printed probe, and a photoconductive switch made from an intrinsic silicon die. Numerical simulations and experiments have been shown to be in agreement, and both demonstrate that the frequency response of the antenna arrays can be efficiently reconfigured over two different frequency ISM bands, namely, 2.4 and 5 GHz. A measured gain of 12.5 dBi has been obtained through the use of two radiating elements printed in a low-cost substrate and a dihedral corner reflector.

  4. Passive wireless antenna sensors for crack detection and shear/compression sensing

    Science.gov (United States)

    Mohammad, Irshad

    Despite the fact that engineering components and structures are carefully designed against fatigue failures, 50 to 90% of mechanical failures are due to fatigue crack development. The severity of the failure depends on both the crack length and its orientation. Many types of sensors are available that can detect fatigue crack propagation. However, crack orientation detection has been rarely reported in the literature. We evaluated a patch antenna sensor capable of detecting crack propagation as well as crack orientation changes. The aim of these sensors would be to evaluate the real-time health condition of metallic structures to avoid catastrophic failures. The proposed crack sensing system consists of a dielectric substrate with a ground plane on one side of the substrate and an antenna patch printed on the other side of the substrate. The ground plane and the antenna patch, both conductive in nature, form an electromagnetic resonant cavity that radiates at distinct frequencies. These frequencies are monitored to evaluate the condition of cracks. A wireless sensor array can be realized by implementing a wireless interrogation unit. The scientific merits of this research are: 1) high sensitivity: it was demonstrated that the antenna sensors can detect crack growth with a sub-millimeter resolution; 2) passive wireless operation: based on microstrip antennas, the antenna sensors encode the sensing information in the backscattered antenna signal and thus can transmit the information without needing a local battery; 3) thin and conformal: the entire sensor unit is less than a millimeter thick and highly conformal; 4) crack orientation detection: the crack orientation on the structure can be precisely evaluated based on a single parameter, which only few sensors can accomplish. In addition to crack detection, the patch antenna sensors are also investigated for measuring shear and pressure forces, with an aim to study the formation, diagnostics and prevention of foot

  5. Analysis of Aperture-coupled Microstrip Antenna Using Method of Moments

    Directory of Open Access Journals (Sweden)

    P. Hajach

    2001-12-01

    Full Text Available A microstrip patch antenna that is coupled to a microstripline by anaperture in the intervening ground plane is analyzed by using themethod of moments. Integral equation is formulated by considering theexact dyadic Green's function in spectral domain for groundeddielectric slab so that the analysis includes all coupling effects andthe radiation and surface wave effects of both substrates. Thecombination of the reciprocity method analysis and a Galerkin momentmethod solution seems to be suitable for a number of planar antennaproblems, especially when coupling slots in the ground plane areincluded. Results for antenna input impedance are compared with otherauthors and verified by experimental results.

  6. Dielectric Covered Planar Antennas at Submillimeter Wavelengths for Terahertz Imaging

    Science.gov (United States)

    Chattopadhyay, Goutam; Gill, John J.; Skalare, Anders; Lee, Choonsup; Llombart, Nuria; Siegel, Peter H.

    2011-01-01

    Most optical systems require antennas with directive patterns. This means that the physical area of the antenna will be large in terms of the wavelength. When non-cooled systems are used, the losses of microstrip or coplanar waveguide lines impede the use of standard patch or slot antennas for a large number of elements in a phased array format. Traditionally, this problem has been solved by using silicon lenses. However, if an array of such highly directive antennas is to be used for imaging applications, the fabrication of many closely spaced lenses becomes a problem. Moreover, planar antennas are usually fed by microstrip or coplanar waveguides while the mixer or the detector elements (usually Schottky diodes) are coupled in a waveguide environment. The coupling between the antenna and the detector/ mixer can be a fabrication challenge in an imaging array at submillimeter wavelengths. Antennas excited by a waveguide (TE10) mode makes use of dielectric superlayers to increase the directivity. These antennas create a kind of Fabry- Perot cavity between the ground plane and the first layer of dielectric. In reality, the antenna operates as a leaky wave mode where a leaky wave pole propagates along the cavity while it radiates. Thanks to this pole, the directivity of a small antenna is considerably enhanced. The antenna consists of a waveguide feed, which can be coupled to a mixer or detector such as a Schottky diode via a standard probe design. The waveguide is loaded with a double-slot iris to perform an impedance match and to suppress undesired modes that can propagate on the cavity. On top of the slot there is an air cavity and on top, a small portion of a hemispherical lens. The fractional bandwidth of such antennas is around 10 percent, which is good enough for heterodyne imaging applications.The new geometry makes use of a silicon lens instead of dielectric quarter wavelength substrates. This design presents several advantages when used in the submillimeter

  7. Ultra wideband antennas design, methodologies, and performance

    CERN Document Server

    Galvan-Tejada, Giselle M; Jardón Aguilar, Hildeberto

    2015-01-01

    Ultra Wideband Antennas: Design, Methodologies, and Performance presents the current state of the art of ultra wideband (UWB) antennas, from theory specific for these radiators to guidelines for the design of omnidirectional and directional UWB antennas. Offering a comprehensive overview of the latest UWB antenna research and development, this book:Discusses the developed theory for UWB antennas in frequency and time domainsDelivers a brief exposition of numerical methods for electromagnetics oriented to antennasDescribes solid-planar equivalen

  8. Multifunctional Antenna Techniques

    Science.gov (United States)

    2015-11-25

    which provides data on the state of the UAV to an application on an Android smart phone. Fig. 11. Spiral antenna mounted to a flying wing UAV...operating at 2.4 GHz was constructed using low-cost off-the- shelf components. Fig. 36 shows a diagram of the physical set-up and block diagram of the system... smart phone applications are underway. This includes using the smart phone to control complex RF systems. An ongoing collaboration between the PI

  9. Ultra wide band antennas

    CERN Document Server

    Begaud, Xavier

    2013-01-01

    Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recog

  10. Nimbus-7 SMMR Antenna Temperatures, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — The SMMR Antenna Temperatures (Nimbus-7) data set consists of antenna temperatures from passive microwave radiometers aboard NOAA's Nimbus-7 satellite. The...

  11. 23 Elemental Composition of Suspended Particulate Matter ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    Elemental Composition of Suspended Particulate Matter Collected at Two Different. Heights above the Ground in A Sub-Urban Site in Kenya. Gitari W. M1, Kinyua A. M. 2, Kamau G. N3 and C. K. Gatebe C. K4. Abstract. Suspended particulate matter samples were collected in a sub-urban area in Nairobi over a 12 month ...

  12. Slot-Coupled Barbel Antenna

    DEFF Research Database (Denmark)

    Jørgensen, Kasper Lüthje; Jakobsen, Kaj Bjarne

    2016-01-01

    A novel slot-coupled barbel antenna is designed and analyzed. A sensitivity analysis performed in order to improve the bandwidth, while the center frequency is kept constant.......A novel slot-coupled barbel antenna is designed and analyzed. A sensitivity analysis performed in order to improve the bandwidth, while the center frequency is kept constant....

  13. Tunable Antennas for Mobile Devices

    DEFF Research Database (Denmark)

    Morris, Art; Barrio, Samantha Caporal Del; Shin, J

    2014-01-01

    Modern mobile terminal design has been driven by the user interface and broadband connectivity. Real world RF performance has substantially fallen recently which impacts data rates, battery life and often causes lost connections. This has been caused by changing antenna location and reduced antenna...

  14. Backfire antennas with dipole elements

    DEFF Research Database (Denmark)

    Nielsen, Erik Dragø; Pontoppidan, Knud

    1970-01-01

    A method is set up for a theoretical investigation of arbitrary backfire antennas based upon dipole structures. The mutual impedance between the dipole elements of the antenna is taken into account, and the field radiated due to a surface wave reflector of finite extent is determined by calculating...

  15. Coupling between minimum scattering antennas

    DEFF Research Database (Denmark)

    Andersen, J.; Lessow, H; Schjær-Jacobsen, Hans

    1974-01-01

    Coupling between minimum scattering antennas (MSA's) is investigated by the coupling theory developed by Wasylkiwskyj and Kahn. Only rotationally symmetric power patterns are considered, and graphs of relative mutual impedance are presented as a function of distance and pattern parameters. Crossed......-dipoles and helices are considered in order to establish a correspondence with simple antenna structures....

  16. Optical antenna enhanced spontaneous emission.

    Science.gov (United States)

    Eggleston, Michael S; Messer, Kevin; Zhang, Liming; Yablonovitch, Eli; Wu, Ming C

    2015-02-10

    Atoms and molecules are too small to act as efficient antennas for their own emission wavelengths. By providing an external optical antenna, the balance can be shifted; spontaneous emission could become faster than stimulated emission, which is handicapped by practically achievable pump intensities. In our experiments, InGaAsP nanorods emitting at ∼ 200 THz optical frequency show a spontaneous emission intensity enhancement of 35 × corresponding to a spontaneous emission rate speedup ∼ 115 ×, for antenna gap spacing, d = 40 nm. Classical antenna theory predicts ∼ 2,500 × spontaneous emission speedup at d ∼ 10 nm, proportional to 1/d(2). Unfortunately, at d < 10 nm, antenna efficiency drops below 50%, owing to optical spreading resistance, exacerbated by the anomalous skin effect (electron surface collisions). Quantum dipole oscillations in the emitter excited state produce an optical ac equivalent circuit current, I(o) = qω|x(o)|/d, feeding the antenna-enhanced spontaneous emission, where q|x(o)| is the dipole matrix element. Despite the quantum-mechanical origin of the drive current, antenna theory makes no reference to the Purcell effect nor to local density of states models. Moreover, plasmonic effects are minor at 200 THz, producing only a small shift of antenna resonance frequency.

  17. The Ultrawideband Leaky Lens Antenna

    NARCIS (Netherlands)

    Bruni, S.; Neto, A.; Marliani, F.

    2007-01-01

    A novel directive and nondispersive antenna is presented: the ultrawideband (UWB) leaky lens. It is based on the broad band Cherenkov radiation occurring at a slot printed between different infinite homogeneous dielectrics. The first part of the paper presents the antenna concept and the UWB design.

  18. Wireless Communication with Multiple Antennas

    Indian Academy of Sciences (India)

    2013-07-05

    Jul 5, 2013 ... Outline of presentation. 1 Information, Uncertainty, and Communication. 2 Capacity of multi-antenna systems. 3 Codes for multi-antenna systems. 4 Well known codes from ECE. 5 Recent patents and concluding remarks. B. Sundar Rajan (ECE). IASc Talk, 05 July 2013. 2 / 31 ...

  19. Antennas for light and plasmons

    NARCIS (Netherlands)

    Dikken, D.J.W.

    2015-01-01

    Antennas have been used for over a century as emitters, scatterers and receivers of electromagnetic waves. All wireless communication devices, such as radio, mobile phones and satellite communication are strongly dependent on the capability of an antenna to localize propagating electromagnetic waves

  20. A Negative Index Metamaterial to Enhance the Performance of Miniaturized UWB Antenna for Microwave Imaging Applications

    Directory of Open Access Journals (Sweden)

    Md. Zulfiker Mahmud

    2017-11-01

    Full Text Available A new, compact planar wideband negative index metamaterial based on a modified split ring resonator (SRR is studied to enhance performance of ultrawideband antenna. A compact, metamaterial (MTM-inspired microstrip antenna is presented for microwave imaging system (MIS application. Two layers of left-handed metamaterial array (2 × 4 of the unit cell are placed on the radiating patch and the ground plane, respectively. Each left-handed metamaterial (LHM unit cell was constructed by modifying a square split ring resonator (SRR, resulting in negative permeability and permittivity with a stable negative refractive index. The results shows that it has a significant impact on the performance of conventional patch antenna in terms of transmission co-efficient, efficiency and low loss. Compared to antenna without LHM, it is shown that the bandwidth is significantly broadened up to a few megahertz and becomes more convergent leading to the achievement of desired properties for ultra-wideband (UWB applications leading to microwave imaging. The proposed MTM antenna structure is fabricated on commercially-available, flame-retardant material of size 26 × 22 × 1.6 mm3 with 4.6 dielectric constants, due to its low cost and convenience for making multilayer printed circuit boards (PCBs. The antenna achieves 3.1 GHz to 10.71 GHz of impedance bandwidth (−10 dB, which covers the full UWB band. The use of double-layer negative index MTM unit cells enhances UWB performance, and the improved radiation efficiency, nearly directional radiation pattern, acceptable gain, stable surface current and negative refractive index make this MTM antenna a suitable candidate for UWB applications.

  1. Minimum Q Electrically Small Antennas

    DEFF Research Database (Denmark)

    Kim, O. S.

    2012-01-01

    Theoretically, the minimum radiation quality factor Q of an isolated resonance can be achieved in a spherical electrically small antenna by combining TM1m and TE1m spherical modes, provided that the stored energy in the antenna spherical volume is totally suppressed. Using closed-form expressions...... for the stored energies obtained through the vector spherical wave theory, it is shown that a magnetic-coated metal core reduces the internal stored energy of both TM1m and TE1m modes simultaneously, so that a self-resonant antenna with the Q approaching the fundamental minimum is created. Numerical results...... for a multiarm spherical helix antenna confirm the theoretical predictions. For example, a 4-arm spherical helix antenna with a magnetic-coated perfectly electrically conducting core (ka=0.254) exhibits the Q of 0.66 times the Chu lower bound, or 1.25 times the minimum Q....

  2. [Hypersensitivity to fluindione (Previscan). Positive skin patch tests].

    Science.gov (United States)

    Frouin, E; Roth, B; Grange, A; Grange, F; Tortel, M-C; Guillaume, J-C

    2005-12-01

    Fluindione (Previscan) is an oral anticoagulant belonging to the vitamin K antagonist class and is very widely used in France. While bleeding is a common complication, severe immunoallergic reactions are less frequent. The authors report a case of drug-induced hypersensitivity syndrome. A 75 year-old woman was hospitalized for diffuse erythematous papular rash associated with facial oedema. These symptoms appeared 3 weeks after the beginning of treatment with fluindione, allopurinol and perindopril. Laboratory tests showed hyperleukocytosis, mixed hepatitis and moderate renal failure, with the entire picture being evocative of drug-induced hypersensitivity reaction. The eruption was associated with eosinophilia, hepatic cytolysis with cholestasis, and acute renale failure. While allopurinol and perindopril were stopped definitively, fluindione was only suspended temporarily following overdosage. On reintroduction, rapid recurrence of clinical and biologic signs was observed with increased severity. The skin rash resolved completely on withdrawal of the drug. Patch tests performed later were positive for fluindione and negative for allopurinol and perindopril. These manifestations were consistent with the diagnosis of drug-induced hypersensitivity syndrome due to fluindione. Very few cases have been described with fluindione despite widespread prescription of the treatment is in France. While there may be no skin involvement, immunoallergic signs such as fever, hepatitis and acute tubular interstitial nephritis have been described with fluindione and these may be related to this syndrome (DRESS - Drug Reaction with Eosinophilia and Systemic Symptoms). Skin patch testing, which is easily performed, can be extremely helpful in determining a causal relationship with medication.

  3. Experimental validation of an ultra-thin metasurface cloak for hiding a metallic obstacle from an antenna radiation at low frequencies

    Science.gov (United States)

    Teperik, Tatiana V.; Burokur, Shah Nawaz; de Lustrac, André; Sabanowski, Guy; Piau, Gérard-Pascal

    2017-07-01

    We demonstrate numerically and experimentally an ultra-thin (≈ λ/240) metasurface-based invisibility cloak for low frequency antenna applications. We consider a monopole antenna mounted on a ground plane and a cylindrical metallic obstacle of diameter smaller than the wavelength located in its near-field. To restore the intrinsic radiation patterns of the antenna perturbed by this obstacle, a metasurface cloak consisting simply of a metallic patch printed on a dielectric substrate is wrapped around the obstacle. Using a finite element method based commercial electromagnetic solver, we show that the radiation patterns of the monopole antenna can be restored completely owing to electromagnetic modes of the resonant cavity formed between the patch and obstacle. The metasurface cloak is fabricated, and the concept is experimentally demonstrated at 125 MHz. Performed measurements are in good agreement with numerical simulations, verifying the efficiency of the proposed cloak.

  4. Improving suspended sediment measurements by automatic samplers.

    Science.gov (United States)

    Gettel, Melissa; Gulliver, John S; Kayhanian, Masoud; DeGroot, Gregory; Brand, Joshua; Mohseni, Omid; Erickson, Andrew J

    2011-10-01

    Suspended solids either as total suspended solids (TSS) or suspended sediment concentration (SSC) is an integral particulate water quality parameter that is important in assessing particle-bound contaminants. At present, nearly all stormwater runoff quality monitoring is performed with automatic samplers in which the sampling intake is typically installed at the bottom of a storm sewer or channel. This method of sampling often results in a less accurate measurement of suspended sediment and associated pollutants due to the vertical variation in particle concentration caused by particle settling. In this study, the inaccuracies associated with sampling by conventional intakes for automatic samplers have been verified by testing with known suspended sediment concentrations and known particle sizes ranging from approximately 20 μm to 355 μm under various flow rates. Experimental results show that, for samples collected at a typical automatic sampler intake position, the ratio of sampled to feed suspended sediment concentration is up to 6600% without an intake strainer and up to 300% with a strainer. When the sampling intake is modified with multiple sampling tubes and fitted with a wing to provide lift (winged arm sampler intake), the accuracy of sampling improves substantially. With this modification, the differences between sampled and feed suspended sediment concentration were more consistent and the sampled to feed concentration ratio was accurate to within 10% for particle sizes up to 250 μm.

  5. Hybrid Maritime Satellite Communication Antenna

    DEFF Research Database (Denmark)

    Smith, Thomas Gunst

    is incorporated in a parabolic FSS reflector antenna that is investigated by full-wave analysis tools, and the antenna shows performance comparable to conventional reflector antennas within its frequency band of operation. A planar prototype FSS is manufactured and measured with particular attention to the impact......Hybrid antennas for a maritime satellite communication terminal with simultaneous operation at L- and Ka-band have been investigated. The frequency bands of interest are 1; 525:0 1; 660:5 MHz (RX+TX, RHCP), 19:7 20:2 (RX, LHCP) and 29:5 30:0 GHz (TX, RHCP), which are all part of the Inmarsat BGAN...... on the performance of an L-band antenna radiating through the FSS. From these investigations, it is concluded that the FSS antenna concept is well suited for hybrid L- and Ka-band operation. A printed reflectarray antenna with FSS ground-plane is demonstrated. The reflectarray produces a collimated beam as a curved...

  6. Formaldehyde concentration in diagnostic patch testing

    DEFF Research Database (Denmark)

    Trattner, A; Johansen, J D; Menné, T

    1998-01-01

    Exposure to formaldehyde is common from both consumer products and industry. The reliability of the patch test is essential for the diagnosis of formaldehyde allergy as it is difficult to suspect from the patient's history. The recommended formaldehyde patch test concentration has been reduced over...... the last decades from 4-5% to 2% and is currently 1%. The changes have not been based upon formal studies, but driven by an intention to reduce irritancy and false-positive results. The aim of the present study was prospectively to compare the outcome of simultaneous testing with formaldehyde 1% and 2......% in consecutively patch-tested patients, with respect to frequency of positive patch test reactions, strength of patch test reactions to different formaldehyde test concentrations, irritancy and relevance. The study included 3734 consecutively patch tested patients. 121 gave a positive reaction to 1% and/or 2...

  7. Composite antenna feed

    Science.gov (United States)

    Jakstys, V. J. (Inventor)

    1973-01-01

    A composite antenna feed subsystem concentrated in a small area at the prime focus of the parabola of a satellite parabolic reflector accomodates a plurality of frequency bands. The arrays comprising the subsystem are mounted on the top cover of a communication module. A multimode horn is arranged at the center of the subsystem axis which functions at X- And C-band frequencies, and a cross array consisting of individual elements form the S-band feed, with one arm of the S-band array containing an element mutually shared with the L-band array. Provision is also made for UHF frequencies, and a dipole arrangement for VHF frequencies is arranged around the S-band arms.

  8. Experimental Multiport Bicone Antenna

    Science.gov (United States)

    Eskelinen, Pekka; Ylinen, Juhana

    2013-01-01

    A practical, easily manufactured multiport bicone antenna suitable for many receiving tasks such as direction finding systems can be made by using sharp-edged metal fins on the feeding coax center conductor to provide a tapered transition and connection path to coaxial probes. This construction resembles an arrow's tail. Already four mutually orthogonal fins can give full 360 degree azimuth coverage with suitable -3 dB port pattern overlap. Five experimental constructions working at Ku and Ka bands, each with fractional bandwidths of 23 to 31 per cent, are shown with full dimensional details. Suitable fin tapering is close to the full air gap in the coax and fin thickness should be less than 1/16th of the outer conductor diameter.

  9. Rydberg Dipole Antennas

    Science.gov (United States)

    Stack, Daniel; Rodenburg, Bradon; Pappas, Stephen; Su, Wangshen; St. John, Marc; Kunz, Paul; Simon, Matt; Gordon, Joshua; Holloway, Christopher

    2017-04-01

    Measurements of microwave frequency electric fields by traditional methods (i.e. engineered antennas) have limited sensitivity and can be difficult to calibrate properly. A useful tool to address this problem are highly-excited (Rydberg) neutral atoms which have very large electric-dipole moments and many dipole-allowed transitions in the range of 1-500 GHz. Using Rydberg states, it is possible to sensitively probe the electric field in this frequency range using the combination of two quantum interference phenomena: electromagnetically induced transparency and the Autler-Townes effect. This atom-light interaction can be modeled by the classical description of a harmonically bound electron. The classical damped, driven, coupled-oscillators model yields significant insights into the deep connections between classical and quantum physics. We will present a detailed experimental analysis of the noise processes in making such measurements in the laboratory and discuss the prospects for building a practical atomic microwave receiver.

  10. A Double-Negative Metamaterial-Inspired Mobile Wireless Antenna for Electromagnetic Absorption Reduction.

    Science.gov (United States)

    Alam, Touhidul; Faruque, Mohammad Rashed Iqbal; Islam, Mohammad Tariqul

    2015-07-29

    A double-negative metamaterial-inspired antenna is presented for mobile wireless applications. The antenna consists of a semi-circular radiating patch and a 3 × 4 hexagonal shaped metamaterial unit cell array in the ground plane. The antenna is fed with a 50 Ω microstrip feed line. The electric dimensions of the proposed antenna are 0.20λ × 0.26λ × 0.004λ, at the low-end frequency. The proposed antenna achieves a -10 dB impedance with a bandwidth of 2.29 GHz at the lower band and 1.28 GHz at the upper band and can operate for most of the mobile applications such as upper GSM bands, WiMAX, Bluetooth, and wireless local area network (WLAN) frequency bands. The focused novelties of the proposed antenna are its small size, multi-standard operating bands, and electromagnetic absorption reduction at all the operating frequencies using the double-negative metamaterial ground plane.

  11. UWB Miniature Antenna Based on the CRLH-TL with Increase Gain for Electromagnetic Requirements

    Directory of Open Access Journals (Sweden)

    M. A. Kenari

    2014-10-01

    Full Text Available In this paper, a novel ultra-wideband (UWB miniature antenna based on the composite right-left handed transmission line (CRLH-TL structure with enhancement gain is proposed and investigated. With CRLH metamaterial (MTM technology embedded, the proposed UWB and miniature antenna is presented with best in bandwidth, size, efficiency and radiation patterns. To realize characteristics of the antenna, the printed -shaped gaps into the rectangular radiation patches are used. This antenna is constructed of the two unit cells, also presented antenna is designed from 2.25 GHz to 4.7 GHz which corresponding to 70.5% bandwidth. The overall size of the presented antenna is 10.8mm×6.9mm×0.8mm or 0.09λ0× 0.05λ0 × 0.006λ0 at the operating frequency f = 2.5 GHz (where λ0 is free space wavelength. The radiation peak gain and the maximum efficiency which occurs at 4.6 GHz, are 3.96dBi and 63.6%, respectively.

  12. Ultrasmall Dual-Band Metamaterial Antennas Based on Asymmetrical Hybrid Resonators

    Directory of Open Access Journals (Sweden)

    Ji-Xu Zhu

    2016-01-01

    Full Text Available A new type of hybrid resonant circuit model is investigated theoretically and experimentally. The resonant model consists of a right hand (RH patch part and a composite right and left handed (CRLH part (RH + CRLH, which determines a compact size and also a convenient frequency modulation characteristic for the proposed antennas. For experimental demonstration, two antennas are fabricated. The former dual-band antenna operating at f-1=3.5 GHz (Wimax and f+1=5.25 GHz (WLAN occupies an area of 0.21λ0×0.08λ0, and two dipolar radiation patterns are obtained with comparable gains of about 6.1 and 6.2 dB, respectively. The latter antenna advances in many aspects such as an ultrasmall size of only 0.16λ0×0.08λ0, versatile radiation patterns with a monopolar pattern at f0=2.4 GHz (Bluetooth, and a dipole one at f+1=3.5 GHz (Wimax and also comparable antenna gains. Circuit parameters are extracted and researched. Excellent performances of the antennas based on hybrid resonators predict promising applications in multifunction wireless communication systems.

  13. Wideband, Low-Profile, Dual-Polarized Slot Antenna with an AMC Surface for Wireless Communications

    Directory of Open Access Journals (Sweden)

    Wei Hu

    2016-01-01

    Full Text Available A wideband dual-polarized slot antenna loaded with artificial magnetic conductor (AMC is proposed for WLAN/WIMAX and LTE applications. The slot antenna mainly consists of two pairs of arrow-shaped slots along the diagonals of the square patch. Stepped microstrip feedlines are placed orthogonally to excite the horizontal and vertical polarizations of the antenna. To realize unidirectional radiation and low profile, an AMC surface composed of 7 × 7 unit cells is designed underneath a distance of 0.09λ0 (λ0 being the wavelength in free space at 2.25 GHz from the slot antenna. Both the dual-polarized slot antenna and the AMC surface are fabricated and measured. Experimental results demonstrate that the proposed antenna achieves for both polarizations a wide impedance bandwidth (return loss 10 dB of 36.7%, operating from 1.96 to 2.84 GHz. The isolation between the two input ports keeps higher than 29 dB whereas the cross-polarization levels basically maintain lower than −30 dB across the entire frequency band. High front-to-back ratios better than 22 dB and a stable gain higher than 8 dBi are obtained over the whole band.

  14. Patch definition in metapopulation analysis: a graph theory approach to solve the mega-patch problem.

    Science.gov (United States)

    Cavanaugh, Kyle C; Siegel, David A; Raimondi, Peter T; Alberto, Filipe

    2014-02-01

    The manner in which patches are delineated in spatially realistic metapopulation models will influence the size, connectivity, and extinction and recolonization dynamics of those patches. Most commonly used patch-definition methods focus on identifying discrete, contiguous patches of habitat from a single temporal observation of species occurrence or from a model of habitat suitability. However, these approaches are not suitable for many metapopulation systems where entire patches may not be fully colonized at a given time. For these metapopulation systems, a single large patch of habitat may actually support multiple, interacting subpopulations. The interactions among these subpopulations will be ignored if the patch is treated as a single unit, a situation we term the "mega-patch problem." Mega-patches are characterized by variable intra-patch synchrony, artificially low inter-patch connectivity, and low extinction rates. One way to detect this problem is by using time series data to calculate demographic synchrony within mega-patches. We present a framework for identifying subpopulations in mega-patches using a combination of spatial autocorrelation and graph theory analyses. We apply our approach to southern California giant kelp (Macrocystis pyrifera) forests using a new, long-term (27 years), satellite-based data set of giant kelp canopy biomass. We define metapopulation patches using our method as well as several other commonly used patch delineation methodologies and examine the colonization and extinction dynamics of the metapopulation under each approach. We find that the relationships between patch characteristics such as area and connectivity and the demographic processes of colonizations and extinctions vary among the different patch-definition methods. Our spatial-analysis/graph-theoretic framework produces results that match theoretical expectations better than the other methods. This approach can be used to identify subpopulations in metapopulations

  15. Patch test sensitivity to Kathon CG.

    Science.gov (United States)

    Hjorth, N; Roed-Petersen, J

    1986-03-01

    Among 1511 consecutive patients patch tested with Kathon CG at 100 ppm active ingredient, 13 (0.8%) gave a positive reaction. Use test with a lotion containing Kathon CG (8.6 ppm) revealed no reaction in 11 patients with a positive patch test. It is concluded that a positive patch test reaction to 100 ppm does not initiate eczema after use of products preserved with Kathon CG in the low concentrations (3-15 ppm) used in final products.

  16. Smart thermal patch for adaptive thermotherapy

    KAUST Repository

    Hussain, Muhammad Mustafa

    2015-11-12

    A smart thermal patch for adaptive thermotherapy is provided. In an embodiment, the patch can be a stretchable, non-polymeric, conductive thin film flexible and non-invasive body integrated mobile thermal heater with wireless control capabilities that can be used to provide adaptive thermotherapy. The patch can be geometrically and spatially tunable on various pain locations. Adaptability allows the amount of heating to be tuned based on the temperature of the treated portion.

  17. Compliance and patching and atropine amblyopia treatments.

    Science.gov (United States)

    Wang, Jingyun

    2015-09-01

    In the past 20 years, there has been a great advancement in knowledge pertaining to compliance with amblyopia treatments. The occlusion dose monitor introduced quantitative monitoring methods in patching, which sparked our initial understanding of the dose-response relationship for patching amblyopia treatment. This review focuses on current compliance knowledge and the impact it has on patching and atropine amblyopia treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Metamaterial antennas: the most successful metamaterial technology?

    DEFF Research Database (Denmark)

    Breinbjerg, Olav

    2015-01-01

    The Thomson Reuters Web of Science™ lists more than 1500 journal articles related to metamaterial antennas from 2001 to 2015; this paper overviews some major objectives of such antennas.......The Thomson Reuters Web of Science™ lists more than 1500 journal articles related to metamaterial antennas from 2001 to 2015; this paper overviews some major objectives of such antennas....

  19. 47 CFR 73.816 - Antennas.

    Science.gov (United States)

    2010-10-01

    ... manufacturer. In no event may composite antennas (i.e., antennas that consist of multiple stacked and/or phased... 47 Telecommunication 4 2010-10-01 2010-10-01 false Antennas. 73.816 Section 73.816... Low Power FM Broadcast Stations (LPFM) § 73.816 Antennas. (a) Permittees and licensees may employ...

  20. Thermal Loss in High-Q Antennas

    DEFF Research Database (Denmark)

    Barrio, Samantha Caporal Del; Bahramzy, Pevand; Svendsen, Simon

    2014-01-01

    Tunable antennas are very promising for future generations of mobile communications, where antennas are required to cover a wide range operating bands. This letter aims at characterizing the loss mechanism of tunable antennas. Tunable antennas typically exhibit a high Quality factor (Q), which can...

  1. Double Structure Broadband Leaky Wave Antenna

    NARCIS (Netherlands)

    Neto, A.; Dijk, R. van; Filippo, M.

    2011-01-01

    A leaky wave antenna contains a first and a second leaky wave antenna structure back to back against each other. Each antenna structure comprises a dielectric body and an elongated wave carrying structure, such as a slot in a conductive ground plane. In each leaky wave antenna structure the body and

  2. Radar Transponder Antenna Systems Evaluation Handbook

    Science.gov (United States)

    2006-07-01

    Trajectory Measurements Group; antenna principles; antenna patterns; EWR 127-1 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT Same as...utility. 15. SUBJECT TERMS Electronic Trajectory Measurements Group; antenna principles; antenna patterns; EWR 127-1 16. SECURITY CLASSIFICATION OF...Considerations of Existing Guideline Documents .......................................... 7-2 7.3 Suggested References To EWR 127-1 Document

  3. 47 CFR 73.510 - Antenna systems.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Antenna systems. 73.510 Section 73.510... Noncommercial Educational FM Broadcast Stations § 73.510 Antenna systems. (a) All noncommercial educational... § 73.316 concerning antenna systems contained in subpart B of this part. (b) Directional antenna. No...

  4. Moths smell with their antennae

    Science.gov (United States)

    Spencer, Thomas; Ballard, Matthew; Alexeev, Alexander; Hu, David

    2015-11-01

    Moths are reported to smell each other from over 6 miles away, locating each other with just 200 airborne molecules. In this study, we investigate how the structure of the antennae influences particle capture. We measure the branching patterns of over 40 species of moths, across two orders of magnitude in weight. We find that moth antennae have 3 levels of hierarchy, with dimensions on each level scaling with body size. We perform lattice-Boltzman simulations to determine optimal flow patterns around antennae branches allowing for capture of small particles.

  5. Smart antennas based on graphene

    Energy Technology Data Exchange (ETDEWEB)

    Aldrigo, Martino; Dragoman, Mircea, E-mail: mircea.dragoman@imt.ro [National Institute for Research and Development in Microtechnology (IMT), P.O. Box 38-160, 023573 Bucharest (Romania); Dragoman, Daniela [Physics Faculty, University of Bucharest, P.O. Box MG-11, 077125 Bucharest (Romania)

    2014-09-21

    We report two configurations of smart graphene antennas, in which either the radiation pattern of the antenna or the backscattering of the periodic metallic arrays is controlled by DC biases that induce metal-insulator reversible transitions of graphene monolayers. Such a transition from a high surface resistance (no bias) to a low surface resistance state (finite bias voltage) causes the radiation pattern of metallic antennas backed with graphene to change dramatically, from omnidirectional to broadside. Moreover, reflectarrays enhance the backscattered field due to the same metal-dielectric transition.

  6. Large inflated-antenna system

    Science.gov (United States)

    Hinson, W. F.; Keafer, L. S.

    1984-01-01

    It is proposed that for inflatable antenna systems, technology feasibility can be demonstrated and parametric design and scalability (scale factor 10 to 20) can be validated with an experiment using a 16-m-diameter antenna attached to the Shuttle. The antenna configuration consists of a thin film cone and paraboloid held to proper shape by internal pressure and a self-rigidizing torus. The cone and paraboloid would be made using pie-shaped gores with the paraboloid being coated with aluminum to provide reflectivity. The torus would be constructed using an aluminum polyester composite that when inflated would erect to a smooth shell that can withstand loads without internal pressure.

  7. Absorption Efficiency of Receiving Antennas

    DEFF Research Database (Denmark)

    Andersen, Jørgen Bach; Frandsen, Aksel

    2005-01-01

    A receiving antenna with a matched load will always scatter some power. This paper sets an upper and a lower bound on the absorption efficiency (absorbed power over sum of absorbed and scattered powers), which lies between 0 and 100% depending on the directivities of the antenna and scatter...... patterns. It can approach 100% as closely as desired, although in practice this may not be an attractive solution. An example with a small endfire array of dipoles shows an efficiency of 93%. Several examples of small conical horn antennas are also given, and they all have absorption efficiencies less than...

  8. Measurement of mobile antenna systems

    CERN Document Server

    Arai, Hiroyuki

    2012-01-01

    If you're involved with the design, installation or maintenance of mobile antenna systems, this thoroughly revised and updated edition of a classic Artech book offers you the most current and comprehensive coverage of all the mandatory measurement techniques you need for your work in the field. This Second Edition presents critical new material in key areas, including radiation efficiency measurement, mobile phone usage position, and MIMO (multiple-input/multiple-output) antennas.This unique resource provides in-depth examinations of all relevant mobile antenna measurement theories, along with

  9. Patch layout generation by detecting feature networks

    KAUST Repository

    Cao, Yuanhao

    2015-02-01

    The patch layout of 3D surfaces reveals the high-level geometric and topological structures. In this paper, we study the patch layout computation by detecting and enclosing feature loops on surfaces. We present a hybrid framework which combines several key ingredients, including feature detection, feature filtering, feature curve extension, patch subdivision and boundary smoothing. Our framework is able to compute patch layouts through concave features as previous approaches, but also able to generate nice layouts through smoothing regions. We demonstrate the effectiveness of our framework by comparing with the state-of-the-art methods.

  10. Group Delay of High Q Antennas

    DEFF Research Database (Denmark)

    Bahramzy, Pevand; Pedersen, Gert Frølund

    2013-01-01

    become an issue, when working with high Q antennas, because of the steep phase shift over the frequency. In this paper, it is measured how large group delay variations can become, when going from a low Q antenna to a high Q antenna. The group delay of a low Q antenna is shown to be around 1.3 ns, whereas...... a high Q antenna has group delay of around 22 ns. It is due to this huge group delay variation characteristics of high Q antennas, that signal distortion might occur in the radio system with high Q antennas....

  11. Full-Wave Analysis of Microstrip Antennas in Three-Layered Spherical Media

    Directory of Open Access Journals (Sweden)

    Tao Yu

    2013-01-01

    Full Text Available A model of three-layered spherical microstrip antenna has been analyzed based on Rao-Wilton-Glisson (RWG triangular basis functions using mixed potential integral equation (MPIE. Firstly, the model of antenna and the dyadic Green’s function in spherical microstrip antennas are given at the beginning of this paper. Then, due to the infinite series convergence problem, asymptotic extraction approach is presented to accelerate the Green’s functions convergence speed when source and field points are located in the same layer and different layers. The convergence speed can be accelerated observably by using this method. Finally, in order to simplify impedance matrix elements calculation at the junction of the probe and patch, a novel division fashion of pair of triangles is adopted in this paper. The input impedance result obtained shows the validity and effectiveness of the analysis method comparing with published data.

  12. CIRCULARLY POLARIZED SLOTTED APERTURE ANTENNA WITH COPLANAR WAVEGUIDE FED FOR BROADBAND APPLICATIONS

    Directory of Open Access Journals (Sweden)

    B. T. P. MADHAV

    2016-02-01

    Full Text Available Coplanar waveguide fed circularly polarized microstrip patch antenna performance evaluation is presented in this paper. The broadband characteristics are attained by placing open end slot at the lower side of the antenna. The proposed design has the return loss of less than -10dB and VSWR<2 in the desired band of operation. A gain of 3dB to 4dB is attained in the desired band with good radiation characteristics and a suitable axial ratio of less than 3 dB is attained in the prescribed band of operation. Proposed antenna is fabricated on the FR4 substrate with dielectric constant of 4.4. Parametric analysis with change in substrate permittivity also performed and the optimized dimensions are presented in this work.

  13. Design strategy for a tunable antenna on a partially magnetized ferrite LTCC substrate

    KAUST Repository

    Ghaffar, Farhan A.

    2014-07-01

    Typical microwave simulators cannot accurately predict the behavior of an antenna on a partially magnetized substrate as they assume the substrate to be in fully saturate state. In this work, a new simulation strategy aided by theoretical analysis, is presented to model a tunable patch antenna on a partially magnetized ferrite substrate through a combination of magnetostatic and microwave simulators. An antenna prototype is fabricated in Ferrite LTCC medium to verify the partially magnetized state simulations. The measured results are in close agreement with the simulations, contrary to the case where the substrate is assumed to be in saturation. The prototype designed for 13 GHz exhibits a tuning range of 10 % making it highly suitable for tunable and reconfigurable wireless applications.

  14. A Compact 5.5 GHz Band-Rejected UWB Antenna Using Complementary Split Ring Resonators

    Directory of Open Access Journals (Sweden)

    M. M. Islam

    2014-01-01

    Full Text Available A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm2, and VSWR < 2, observing band elimination of 5.5 GHz WLAN band.

  15. A compact 5.5 GHz band-rejected UWB antenna using complementary split ring resonators.

    Science.gov (United States)

    Islam, M M; Faruque, M R I; Islam, M T

    2014-01-01

    A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs) is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm(2), and VSWR < 2, observing band elimination of 5.5 GHz WLAN band.

  16. A U-Shaped Slot UWB Antenna with Flexible and Wide Tunable Dual Notch Band

    Directory of Open Access Journals (Sweden)

    Zhang Zhongmin

    2016-01-01

    Full Text Available A coplanar waveguide (CPW fed ultra-wideband (UWB antenna with flexible and wide tunable dual bandnotched characteristics is proposed in this paper. The dual band-notched function is achieved by using an U-shaped slot inserted into the ellipse radiation patch and by using an elliptic parasitic slit placed near the ground plane. The wide tunable band-notched characteristic is implemented by adjusting the length of U-shaped slot and by adjusting the length of ellipse parasitic slit. The design aims to achieve wide reconfigurable band-notched features on the UWB antenna. The simulated results indicate that the proposed antenna has a wide bandwidth (VSWR under 2 from 2.9GHz to 12.6GHz with fractional bandwidth of 125%, and has a wide tunable notch band center frequency from 4.5GHz to 12.4GHz.

  17. 3D-Printed Super-Wideband Spidron Fractal Cube Antenna with Laminated Copper

    Directory of Open Access Journals (Sweden)

    Oh Heon Kwon

    2017-09-01

    Full Text Available In this paper, a 3D-printed super-wideband (SWB Spidron fractal cube antenna is proposed. The Spidron fractal configuration is utilized as a self-complementary structure on each face of a 3D frame to attain SWB characteristics. The antenna is excited through a tapered microstrip balun for both mode transforming and impedance matching. A prototype of the proposed antenna, including the 3D frame fabricated with the help of a 3D printer and Spidron fractal patches made of copper tape, is experimentally verified. The measured −10 dB reflection ratio bandwidth is 34:1 (0.44–15.38 GHz. The peak gain varies from 3.42 to 9.29 dBi within the operating frequency bandwidth. The measured radiation patterns are nearly omnidirectional at all operating frequency bands.

  18. A Multibeam Dual-Band Orthogonal Linearly Polarized Antenna Array for Satellite Communication on the Move

    Directory of Open Access Journals (Sweden)

    Yi Liu

    2015-01-01

    Full Text Available The design and simulation of a 10 × 8 multibeam dual-band orthogonal linearly polarized antenna array operating at Ku-band are presented for transmit-receive applications. By using patches with different coupling methods as elements, both perpendicular polarization in 12.25–12.75 GHz band and horizontal polarization in 14.0–14.5 GHz band are realized in a shared antenna aperture. A microstrip Rotman lens is employed as the beamforming network with 7 input ports, which can generate a corresponding number of beams to cover −30°–30° with 5 dB beamwidth along one dimension. This type of multibeam orthogonal linearly polarized planar antenna is a good candidate for satellite communication (SatCom.

  19. Electrically floating, near vertical incidence, skywave antenna

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Allen A.; Kaser, Timothy G.; Tremblay, Paul A.; Mays, Belva L.

    2014-07-08

    An Electrically Floating, Near Vertical Incidence, Skywave (NVIS) Antenna comprising an antenna element, a floating ground element, and a grounding element. At least part of said floating ground element is positioned between said antenna element and said grounding element. The antenna is separated from the floating ground element and the grounding element by one or more electrical insulators. The floating ground element is separated from said antenna and said grounding element by one or more electrical insulators.

  20. Design and Simulation of a Novel Broadband Circularly Polarized Microstrip Slot Antenna

    Directory of Open Access Journals (Sweden)

    Elaheh Shirazi

    2016-06-01

    Full Text Available In this paper, a novel broadband printed circularly polarized microstrip slot antenna fed by a co planar wave guide (CPW is designed, analyzed and simulated. The structure of the proposed antenna is made of a modified stair-shaped patch in conjunction with a square ground plane with a stair-shaped slot inside it. By using a modified stair-shaped patch and square ground plane, additional resonances are excited and, hence, much wider impedance bandwidth can be produced, especially at the higher band. Moreover, by using this structure, especially by adding two rectangular strip to the ground plane, very broadband axial-ratio bandwidth is obtained. the proposed antenna has dimensions of 45×45×0.8 mm3, which is compatible with the requirements imposed by portable wireless systems. Simulation results exhibits a 81.7% (2.78-6.62 GHz -10 dB impedance bandwidth and a 57.6% (3.5-6.33 GHz 3 dB axial-ratio bandwidth. the antenna performance confirms its viability for commercial portable wireless systems.

  1. Dipoles, unintentional antennas and EMC

    Directory of Open Access Journals (Sweden)

    Berend Danker

    2008-01-01

    Full Text Available Radiated emissions from equipment commonly originate from electronic circuits that act as electric dipoles created by the signal voltage between the signal conductors or as magnetic dipoles formed by the signal current flowing in a loop. Direct emission is mostly small, but circuits often couple to long conductors or large wiring loops which act as antennas and are efficient radiators. A comparable situation exists when short dipole antennas or small wiring loops receive ambient noise (susceptibility. Usually the amplitude of noise sources or the susceptibility of circuits is an invariable. The dipole strength increases with the distance between the conductors and the area. Shielding and proper grounding decreases the interaction via unintentional antennas. Short-circuiting and the insertion of lossy ferrite cores reduce the efficiency of unintentional antennas.

  2. Configurable Conformal Impulse Receive Antenna

    National Research Council Canada - National Science Library

    Kirk, G. H

    2005-01-01

    Among leading-edge research concerns in ultra-wideband (UWB) radiofrequency (RF) methods, it has recently become important to devise antennas to satisfy the following conditions as much as possible: (a) be UWB responsive; (b...

  3. Diversity Gain through Antenna Blocking

    Directory of Open Access Journals (Sweden)

    V. Dehghanian

    2012-01-01

    Full Text Available As part of the typical usage mode, interaction between a handheld receiver antenna and the operator's RF absorbing body and nearby objects is known to generate variability in antenna radiation characteristics through blocking and pattern changes. It is counterintuitive that random variations in blocking can result in diversity gain of practical applicability. This diversity gain is quantified from a theoretical and experimental perspective. Measurements carried out at 1947.5 MHz verify the theoretical predictions, and a diversity gain of 3.1 dB was measured through antenna blocking and based on the utilized measurement setup. The diversity gain can be exploited to enhance signal detectability of handheld receivers based on a single antenna in indoor multipath environments.

  4. Stub loaded low profile loop patch antennna on a finite ground plane

    DEFF Research Database (Denmark)

    Thaysen, Jesper; Jakobsen, Kaj Bjarne

    2004-01-01

    A small 1.7 cm3 one-turn loop patch antenna located 2.5 mm above an 18 x 38 mm2 ground plane separated by a dielctric substrate with a relative permittivity of 9.8 is presented. A chip balun is used to accomplish the balanced feed for the loop antenna. By the use of a thin matching transmission...... line it is possible to chance the resonant frequency. The best performance is obtained, when the matching line has a length of a quarter of a wavelength. In addition the thin matching line also improves the impedance match, and it is thus possible to obtain a 9.6% bandwidth at the resonant frequency...

  5. Fast exact nearest patch matching for patch-based image editing and processing.

    Science.gov (United States)

    Xiao, Chunxia; Liu, Meng; Nie, Yongwei; Dong, Zhao

    2011-08-01

    This paper presents an efficient exact nearest patch matching algorithm which can accurately find the most similar patch-pairs between source and target image. Traditional match matching algorithms treat each pixel/patch as an independent sample and build a hierarchical data structure, such as kd-tree, to accelerate nearest patch finding. However, most of these approaches can only find approximate nearest patch and do not explore the sequential overlap between patches. Hence, they are neither accurate in quality nor optimal in speed. By eliminating redundant similarity computation of sequential overlap between patches, our method finds the exact nearest patch in brute-force style but reduces its running time complexity to be linear on the patch size. Furthermore, relying on recent multicore graphics hardware, our method can be further accelerated by at least an order of magnitude (≥10×). This greatly improves performance and ensures that our method can be efficiently applied in an interactive editing framework for moderate-sized image even video. To our knowledge, this approach is the fastest exact nearest patch matching method for high-dimensional patch and also its extra memory requirement is minimal. Comparisons with the popular nearest patch matching methods in the experimental results demonstrate the merits of our algorithm. © 2011 IEEE

  6. Antenna design for mobile devices

    CERN Document Server

    Zhang, Zhijun

    2017-01-01

    - Integrates state-of-the-art technologies with a special section for step-by-step antenna design - Features up-to-date bio-safety and electromagnetic compatibility regulation compliance and latest standards - Newly updated with MIMO antenna design, measurements and requirements - Accessible to readers of many levels, from introductory to specialist - Written by a practicing expert who has hired and trained numerous engineers

  7. Omnidirectional antenna for radar applications

    Science.gov (United States)

    Vitiello, R.

    The development of an omnidirectional antenna for sidelobe blanking is described. The results of electrical measurements for an S-band and L-band configuration are given. The antenna architecture consists of eight printed radiating elements arranged in a biconical fashion. The single radiating element is a pseudo log periodic microstrip array fed by means of capacitive coupling. Modularity and flexibility are the outstanding characteristics of the design.

  8. Radar techniques using array antennas

    CERN Document Server

    Wirth, Wulf-Dieter

    2013-01-01

    Radar Techniques Using Array Antennas is a thorough introduction to the possibilities of radar technology based on electronic steerable and active array antennas. Topics covered include array signal processing, array calibration, adaptive digital beamforming, adaptive monopulse, superresolution, pulse compression, sequential detection, target detection with long pulse series, space-time adaptive processing (STAP), moving target detection using synthetic aperture radar (SAR), target imaging, energy management and system parameter relations. The discussed methods are confirmed by simulation stud

  9. Living antennas on communication satellites

    DEFF Research Database (Denmark)

    Lumholt, Michael

    2003-01-01

    Crises change the global pattern of communication. The communications problems occur because the satellites are optimized to cover specific geographic areas, and these areas cannot be altered once the satellites are in Earth orbit. An effective solution to the problem is to equip communication...... satellites with "living" antennas that can adjust their radiation coverage areas according to the new demands. The development of living antennas is, therefore, among the focus areas identified and supported by the European Space Agency, ESA....

  10. Electromagnetic antenna modeling (EAM) system

    Science.gov (United States)

    Packer, Malcolm; Powers, Robert; Tsitsopoulos, Paul

    1994-12-01

    The determination of foreign communications capabilities and intent is an important assessment function performed by the USAF National Air Intelligence Center (NAIC). In this context, Rome Laboratory became the NAIC engineering agent for the development of an NAIC requirement for the rapid analysis and evaluation of antenna structures based on often vague to sometimes detailed dimensional information. To this end, the Rome Laboratory sponsored development of the Electromagnetic Antenna Modeling (EAM) System, a state-of-the-art Pascal program with an MS Windows graphical user interface (GUI) pre- and post-processor. Users of NAIC capabilities initiate antenna analysis efforts that range from simple parametric studies to more complex, detailed antenna design and communication-system evaluations. Accordingly, EAM provides a modeling capability 'matched' to the sophistication of the individual analyst, with features appropriate for users ranging from nontechnical analysts to experienced antenna engineers. This capability is particularly valuable in the military-intelligence environment, in which high-speed assessments are required. In particular, EAM meets the specific antenna-analysis requirements of NAIC with a versatile graphical user interface.

  11. Gravity Survey of the Rye Patch KGRA, Rye Patch, Nevada

    Science.gov (United States)

    Mcdonald, M. R.; Gosnold, W. D.

    2011-12-01

    The Rye Patch Known Geothermal Resource Area (KGRA) is located in Pershing County Nevada on the west side of the Humboldt Range and east of the Rye Patch Reservoir approximately 200 km northeast of Reno, Nevada. Previous studies include an earlier gravity survey, 3-D seismic reflection, vertical seismic profiling (VSP) on a single well, 3-D seismic imaging, and a report of the integrated seismic studies. Recently, Presco Energy conducted an aeromagnetic survey and is currently in the process of applying 2-D VSP methods to target exploration and production wells at the site. These studies have indicated that geothermal fluid flow primarily occurs along faults and fractures and that two potential aquifers include a sandstone/siltstone member of the Triassic Natchez Pass Formation and a karst zone that occurs at the interface between Mesozoic limestone and Tertiary volcanics. We hypothesized that addition of a high-resolution gravity survey would better define the locations, trends, lengths, and dip angles of faults and possible solution cavity features. The gravity survey encompassed an area of approximately 78 km2 (30 mi2) within the boundary of the KGRA along with portions of 8 sections directly to the west and 8 sections directly to the east. The survey included 203 stations that were spaced at 400 m intervals. The simple Bouguer anomaly patterns were coincident with elevation, and those patterns remained after terrain corrections were performed. To remove this signal, the data were further processed using wave-length (bandpass) filtering techniques. The results of the filtering and comparison with the recent aeromagnetic survey indicate that the location and trend of major fault systems can be identified using this technique. Dip angles can be inferred by the anomaly contour gradients. By further reductions in the bandpass window, other features such as possible karst solution channels may also be recognizable. Drilling or other geophysical methods such as a

  12. The Ideal Base For Patch Testing

    Directory of Open Access Journals (Sweden)

    Ashok Kumar Bajaj

    1984-01-01

    Full Text Available A study was conducted to find out a suitable vehicle for patch testing in India. Various bases: tested were petrolatum, propylene glycol, polyethylene glycol 400, lanolin, olive, oil and plastobase. The observations suggest that polythylene glycol 400 is the most suitable vehicle for patch testing.

  13. Transdermal patches: history, development and pharmacology.

    Science.gov (United States)

    Pastore, Michael N; Kalia, Yogeshvar N; Horstmann, Michael; Roberts, Michael S

    2015-05-01

    Transdermal patches are now widely used as cosmetic, topical and transdermal delivery systems. These patches represent a key outcome from the growth in skin science, technology and expertise developed through trial and error, clinical observation and evidence-based studies that date back to the first existing human records. This review begins with the earliest topical therapies and traces topical delivery to the present-day transdermal patches, describing along the way the initial trials, devices and drug delivery systems that underpin current transdermal patches and their actives. This is followed by consideration of the evolution in the various patch designs and their limitations as well as requirements for actives to be used for transdermal delivery. The properties of and issues associated with the use of currently marketed products, such as variability, safety and regulatory aspects, are then described. The review concludes by examining future prospects for transdermal patches and drug delivery systems, such as the combination of active delivery systems with patches, minimally invasive microneedle patches and cutaneous solutions, including metered-dose systems. © 2015 The British Pharmacological Society.

  14. Immunoisolation Patch System for Cellular Transplantation

    Science.gov (United States)

    Wang, Taylor G. (Inventor)

    2014-01-01

    An immunoisolation patch system, and particularly a patch system comprising multiple immunoisolation microcapsules, each encapsulating biological material such as cells for transplantation, which can be used in the prophylactic and therapeutic treatment of disease in large animals and humans without the need for immunosuppression.

  15. Compact Planar Ultrawideband Antennas with 3.5/5.2/5.8 GHz Triple Band-Notched Characteristics for Internet of Things Applications.

    Science.gov (United States)

    Dong, Jian; Li, Qianqian; Deng, Lianwen

    2017-02-10

    Ultrawideband (UWB) antennas, as core devices in high-speed wireless communication, are widely applied to mobile handsets, wireless sensor networks, and Internet of Things (IoT). A compact printed monopole antenna for UWB applications with triple band-notched characteristics is proposed in this paper. The antenna has a very compact size of 10 x 16 mm2 and is composed of a square slotted radiation patch and a narrow rectangular ground plane on the back of the substrate. First, by etching a pair of inverted T-shaped slots at the bottom of the radiation patch, one notched band at 5-6 GHz for rejecting the Wireless Local Area Network (WLAN) is generated. Then, by cutting a comb-shaped slot on the top of the radiation patch, a second notched band for rejecting 3.5 GHz Worldwide Interoperability for Microwave Access (WiMAX) is obtained. Further, by cutting a pair of rectangular slots and a C-shaped slot as well as adding a pair of small square parasitic patches at the center of the radiating patch, two separate notched bands for rejecting 5.2 GHz lower WLAN and 5.8 GHz upper WLAN are realized, respectively. Additionally, by integrating the slotted radiation patch with the narrow rectangular ground plane, an enhanced impedance bandwidth can be achieved, especially at the higher band. The antenna consists of linear symmetrical sections only and is easy for fabrication and fine-tuning. The measured results show that the designed antenna provides a wide impedance bandwidth of 150% from 2.12 to 14.80 GHz for VSWR good frequency-domain and time-domain performances at desired UWB frequencies and be an attractive candidate for portable IoT applications.

  16. Antenna Miniaturization in Complex Electromagnetic Environments

    DEFF Research Database (Denmark)

    Zhang, Jiaying

    with stringent specifications makes the antenna size reduction a significant challenge. Antenna miniaturization is thus one of the key technologies in designing a successful wireless unit for the hearing-aid application. This dissertation is focused on three areas that are related to the integration of a wire......- less communication system into the heading-aids, and these are the antenna miniaturization, the measurement techniques for electrically small antennas and the influence of complex environments on the characteristics of electrically small antennas, respectively. Antenna Miniaturization......In this dissertation, we present several novel designs of electrically small loop antennas for the hearing-aid application. First antenna design is a two-dimensional (2-D) planar differential-fed electrically small loop. The working mechanism of this antenna is based on the capacitive loading and the induc- tive...

  17. Some Recent Developments of Microstrip Antenna

    Directory of Open Access Journals (Sweden)

    Yong Liu

    2012-01-01

    Full Text Available Although the microstrip antenna has been extensively studied in the past few decades as one of the standard planar antennas, it still has a huge potential for further developments. The paper suggests three areas for further research based on our previous works on microstrip antenna elements and arrays. One is exploring the variety of microstrip antenna topologies to meet the desired requirement such as ultrawide band (UWB, high gain, miniaturization, circular polarization, multipolarized, and so on. Another is to apply microstrip antenna to form composite antenna which is more potent than the individual antenna. The last is growing towards highly integration of antenna/array and feeding network or operating at relatively high frequencies, like sub-millimeter wave or terahertz (THz wave regime, by using the advanced machining techniques. To support our points of view, some examples of antennas developed in our group are presented and discussed.

  18. Image quality assessment based on inter-patch and intra-patch similarity.

    Directory of Open Access Journals (Sweden)

    Fei Zhou

    Full Text Available In this paper, we propose a full-reference (FR image quality assessment (IQA scheme, which evaluates image fidelity from two aspects: the inter-patch similarity and the intra-patch similarity. The scheme is performed in a patch-wise fashion so that a quality map can be obtained. On one hand, we investigate the disparity between one image patch and its adjacent ones. This disparity is visually described by an inter-patch feature, where the hybrid effect of luminance masking and contrast masking is taken into account. The inter-patch similarity is further measured by modifying the normalized correlation coefficient (NCC. On the other hand, we also attach importance to the impact of image contents within one patch on the IQA problem. For the intra-patch feature, we consider image curvature as an important complement of image gradient. According to local image contents, the intra-patch similarity is measured by adaptively comparing image curvature and gradient. Besides, a nonlinear integration of the inter-patch and intra-patch similarity is presented to obtain an overall score of image quality. The experiments conducted on six publicly available image databases show that our scheme achieves better performance in comparison with several state-of-the-art schemes.

  19. Robustness of metacommunities with omnivory to habitat destruction: disentangling patch fragmentation from patch loss.

    Science.gov (United States)

    Liao, Jinbao; Bearup, Daniel; Wang, Yeqiao; Nijs, Ivan; Bonte, Dries; Li, Yuanheng; Brose, Ulrich; Wang, Shaopeng; Blasius, Bernd

    2017-06-01

    Habitat destruction, characterized by patch loss and fragmentation, is a major driving force of species extinction, and understanding its mechanisms has become a central issue in biodiversity conservation. Numerous studies have explored the effect of patch loss on food web dynamics, but ignored the critical role of patch fragmentation. Here we develop an extended patch-dynamic model for a tri-trophic omnivory system with trophic-dependent dispersal in fragmented landscapes. We found that species display different vulnerabilities to both patch loss and fragmentation, depending on their dispersal range and trophic position. The resulting trophic structure varies depending on the degree of habitat loss and fragmentation, due to a tradeoff between bottom-up control on omnivores (dominated by patch loss) and dispersal limitation on intermediate consumers (dominated by patch fragmentation). Overall, we find that omnivory increases system robustness to habitat destruction relative to a simple food chain. © 2017 by the Ecological Society of America.

  20. Patch shape, connectivity, and foraging by oldfield mice (Peromyscus polionotus).

    Energy Technology Data Exchange (ETDEWEB)

    Orrock, John, L.; Danielson, Brent J

    2005-06-01

    We examined how corridors and patch shape affect foraging by the oldfield mouse (Peromyscus polionotus) by deploying foraging trays and live traps in experimental landscapes with 3 different patch types: patches connected with a corridor, unconnected patches with projecting corridorlike portions (winged patches), and unconnected rectangular patches. Corridors did not lead to different levels of activity of P. polionotus among the 3 patch types. Rather, corridors influenced activity by changing patch shape: foraging in seed trays and total number of captures of P. polionotus tended to be greater at the patch center than at the patch edge, but only in connected and winged patches where corridors or wings increased the amount of patch edge relative to the amount of core habitat in the patch. P. polionotus avoided open microhabitats near the patch edge in winged and connected patches, but not open microhabitats near the patch interior, suggesting that predation risk caused shifts in foraging near edges in connected and winged patches. Foraging in corridors and wings was generally low, suggesting that both are high-risk habitats where predation risk is not ameliorated by proximity to vegetative cover. By changing patch shape, corridors caused changes in within-patch activity of P. polionotus, changing foraging patterns and potentially altering the dynamics of P. polionotus and the seeds they consume.

  1. Triple Band Parasitic Array Antenna for C-X-Ku-Band Application Using Out-of-Phase Coupling Approach

    Directory of Open Access Journals (Sweden)

    Anubhuti Khare

    2014-01-01

    Full Text Available Triple band parasitic array antenna for C-X-Ku-band application is presented. The proposed antenna is designed using the concept of parasitic array and out-of-phase coupling approach. The objects of research are to optimize total inductance of geometry by using out-of-phase inductance approach. The out of phase inductance of geometry consists of using two U-patches novel director on the left side of geometry, appropriate dimension of ground plan, and gap coupling between parasitic and active patches. The dimension of the ground plan geometry is 0.5λ mil × 0.5154λ mil. The usable impedance bandwidth of design antenna is “5.8 GHz to 18 GHz” (102% impedance bandwidth and gain enhancement is up to 11.8 dBi. The proposed antenna can be used for X-Ku band and C-band applications. Both simulated and measured results are presented, which are in good agreement. The proposed antenna was fabricated with a thin copper layer printed on a thin lossy FR4 substrate for low-cost production.

  2. Combining the switched-beam and beam-steering capabilities in a 2-D phased array antenna system

    Science.gov (United States)

    Tsai, Yi-Che; Chen, Yin-Bing; Hwang, Ruey-Bing

    2016-01-01

    This paper presents the development, fabrication, and measurement of a novel beam-forming system consisting of 16 subarray antennas, each containing four aperture-coupled patch antennas, and the application of this system in smart wireless communication systems. The beam patterns of each of the subarray antennas can be switched toward one of nine zones over a half space by adjusting the specific phase delay angles among the four antenna elements. Furthermore, when all subarrays are pointed at the same zone, slightly continuous beam steering in around 1° increments can be achieved by dynamically altering the progressive phase delay angle among the subarrays. Phase angle calibration was implemented by coupling each transmitter output and down converter into the in-phase/quadrature baseband to calculate the correction factor to the weight. In addition, to validate the proposed concepts and the fabricated 2-D phased array antenna system, this study measured the far-field radiation patterns of the aperture-coupled patch array integrated with feeding networks and a phase-calibration system to carefully verify its spatially switched-beam and beam-steering characteristics at a center frequency of 2.4 GHz which can cover the industrial, scientific, and medical band and some long-term evolution applications. In addition, measured results were compared with calculated results, and agreement between them was observed.

  3. Vehicle antenna development for mobile satellite applications

    Science.gov (United States)

    Woo, K.

    1988-01-01

    The paper summarizes results of a vehicle antenna program at JPL in support of a developing U.S. mobile satellite services (MSS) designed to provide telephone and data services for the continental United States. Two classes of circularly polarized vehicle antennas have been considered for the MSS: medium-gain, satellite-tracking antennas with 10-12-dBic gain; and low-gain, azimuthally omnidirectional antennas with 3-5-dBic gain. The design and performance of these antennas are described, and the two antennas are shown to have peculiar advantages and disadvantages.

  4. Let's play with the parabolic antenna!

    Science.gov (United States)

    Ishihara, Yuko

    2006-03-01

    By collaborating with the Nobeyama Radio Observatory, we developed a teaching material where one can play and learn how a parabolic antenna collects radio waves. The antenna is now on exhibit at Koriyama City Fureai Science Center. Superballs help the user to visualize the mechanism of a parabolic antenna. The antenna used in the exhibit was originally a part of a radio telescope. More than a year has passed since the development and the exhibition. We report about the applied use of the antenna inside and outside our science center and about parabolic antennas in other museums and observatories.

  5. Modern lens antennas for communications engineering

    CERN Document Server

    Thornton, John

    2012-01-01

    The aim of this book is to present the modern design principles and analysis of lens antennas. It gives graduates and RF/Microwave professionals the design insights in order to make full use of lens antennas.  Why do we want to write a book in lens antennas? Because this topic has not been thoroughly publicized, its importance is underestimated. As antennas play a key role in communication systems, recent development in wireless communications would indeed benefit from the characteristics of lens antennas: low profile, and low cost etc.  The major advantages of lens antennas are na

  6. VAlidation STandard antennas: Past, present and future

    DEFF Research Database (Denmark)

    Drioli, Luca Salghetti; Ostergaard, A; Paquay, M

    2011-01-01

    designed for validation campaigns of antenna measurement ranges. The driving requirements of VAST antennas are their mechanical stability over a given operational temperature range and with respect to any orientation of the gravity field. The mechanical design shall ensure extremely stable electrical....../V-band of telecom satellites. The paper will address requirements for future VASTs and possible architecture for multi-frequency Validation Standard antennas........ In the beginning, ad-hoc available antennas were shipped around the various ranges. Soon it became clear that the comparisons were restricted by the properties of the antenna. The European Space Agency (ESA) stimulated and supported the development of a dedicated VAlidation STandard (VAST) antenna, specifically...

  7. Compressive Sensing for Blockage Detection in Vehicular Millimeter Wave Antenna Arrays

    KAUST Repository

    Eltayeb, Mohammed E.

    2017-02-07

    The radiation pattern of an antenna array depends on the excitation weights and the geometry of the array. Due to mobility, some vehicular antenna elements might be subjected to full or partial blockages from a plethora of particles like dirt, salt, ice, and water droplets. These particles cause absorption and scattering to the signal incident on the array, and as a result, change the array geometry. This distorts the radiation pattern of the array mostly with an increase in the sidelobe level and decrease in gain. In this paper, we propose a blockage detection technique for millimeter wave vehicular antenna arrays that jointly estimates the locations of the blocked antennas and the attenuation and phase-shifts that result from the suspended particles. The proposed technique does not require the antenna array to be physically removed from the vehicle and permits real-time array diagnosis. Numerical results show that the proposed technique provides satisfactory results in terms of block detection with low detection time provided that the number of blockages is small compared to the array size.

  8. A wideband rectangular-ring textile antenna integrated with corner-notched artificial magnetic conductor (AMC) plane

    Science.gov (United States)

    Aun, N. F. M.; Soh, P. J.; Jamlos, M. F.; Lago, H.; Al-Hadi, A. A.

    2017-01-01

    This paper presents the design of a wideband artificial magnetic conductor (AMC) for operation in the Wireless Body Area Network Ultra Wideband (WBAN-UWB) mandatory channel 6. The proposed AMC is incorporated onto a rectangular-ring patch antenna for operation centered at 8 GHz with 2 GHz of bandwidth. The incorporation of the AMC improved the antenna reflection coefficient and impedance bandwidth, besides shielding the radiator against on-body detuning. The prototype is fully fabricated using textiles except for an SMA connector used for feeding. It is observed that the experimental results are in good agreement with the simulations, and bandwidth broadening is successfully achieved and validated.

  9. Generic Patch Inference

    DEFF Research Database (Denmark)

    Andersen, Jesper; Lawall, Julia Laetitia

    2008-01-01

    A key issue in maintaining Linux device drivers is the need to update drivers in response to evolutions in Linux internal libraries. Currently, there is little tool support for performing and documenting such changes. In this paper we present a tool, spfind, that identifies common changes made...... in a set of pairs of files and their updated versions, and extracts a generic patch performing those changes. Library developers can use our tool to extract a generic patch based on the result of manually updating a few typical driver files, and then apply this generic patch to other drivers.  Driver...

  10. Streamlining of plant patches in streams

    DEFF Research Database (Denmark)

    Jensen, Kaj Sand; Pedersen, Morten Lauge

    2008-01-01

    1. Plants in shallow streams often grow in well-defined monospecific patches experiencing a predictable unidirectional flow, though of temporally variable velocity. During maximum patch development in summer we studied: (i) the shape and streamlining of 59 patches of Callitriche cophocarpa, (ii...... gradients developed across the exposed outer surfaces as the diverted flow accelerated. Because drag processes are additive, and exist at different spatial scales and Reynolds numbers on the surface and inside of plant canopies, direct measurements on entire canopies under controlled conditions are needed...

  11. Efficient Design of Flexible and Low Cost Paper-Based Inkjet-Printed Antenna

    Directory of Open Access Journals (Sweden)

    A. M. Mansour

    2015-01-01

    Full Text Available A new, efficient, flexible, and cheap antenna designed at 1.57 GHz microstrip patch antenna based on simple inkjet printer with improved performance using silver nanoparticles ink is developed. The antenna is printed on a kind of flexible substrate “glossy paper,” to offer the advantage of light and flexibility for different applications. The performance of silver nanoparticles ink has been studied through inkjet printing versus postsynthesis annealing and multilayer printing. The conductivity has been improved to have promising values up to 2 Ω/cm at temperatures up to 180°C. The surface morphology of the circuits has been analyzed using SEM with mean diameter of the nanoparticles around 100 nm, uniform surface distribution, and mean thickness of the printed layer around 230 microns. Also, a simple design of a coplanar waveguide (CPW monopole Z-shaped antenna has been considered as an application of fabricated printed antenna using the studied silver nanoparticles ink through a cheap printer.

  12. Theory and design of a tunable antenna on a partially magnetized ferrite LTCC substrate

    KAUST Repository

    Ghaffar, Farhan A.

    2014-03-01

    For the first time, a theoretical model is presented to predict the frequency tuning of a patch antenna on a partially magnetized ferrite substrate. Both extraordinary (E) and ordinary (O) modes of the antenna are studied. The permeability tensor of the partially magnetized ferrite is calculated through the proposed theoretical model and is subsequently used to analyze the antenna\\'s performance in a microwave simulator. Prototype antennas were built, using two different bias windings, embedded in a multilayer ferrite LTCC substrate, to demonstrate E and O mode tuning. The use of embedded windings negates the requirement of bulky electromagnets, thus providing miniaturization. The concept also eliminates the demagnetization effect, thus reducing the typically required bias fields by 95%. The prototype measurements at 13 GHz demonstrate an E-mode tuning range of 10%. The proposed theoretical model has been validated by simulations and measurements. The design is highly suitable for compact, light-weight, tunable and reconfigurable microwave systems. © 1963-2012 IEEE.

  13. Low-cost dielectric substrate for designing low profile multiband monopole microstrip antenna.

    Science.gov (United States)

    Ahsan, M R; Islam, M T; Habib Ullah, M; Arshad, H; Mansor, M F

    2014-01-01

    This paper proposes a small sized, low-cost multiband monopole antenna which can cover the WiMAX bands and C-band. The proposed antenna of 20 × 20 mm(2) radiating patch is printed on cost effective 1.6 mm thick fiberglass polymer resin dielectric material substrate and fed by 4 mm long microstrip line. The finite element method based, full wave electromagnetic simulator HFSS is efficiently utilized for designing and analyzing the proposed antenna and the antenna parameters are measured in a standard far-field anechoic chamber. The experimental results show that the prototype of the antenna has achieved operating bandwidths (voltage stand wave ratio (VSWR) less than 2) 360 MHz (2.53-2.89 GHz) and 440 MHz (3.47-3.91 GHz) for WiMAX and 1550 MHz (6.28-7.83 GHz) for C-band. The simulated and measured results for VSWR, radiation patterns, and gain are well matched. Nearly omnidirectional radiation patterns are achieved and the peak gains are of 3.62 dBi, 3.67 dBi, and 5.7 dBi at 2.66 GHz, 3.65 GHz, and 6.58 GHz, respectively.

  14. Prospective randomized study of carotid endarterectomy with Fluoropassiv thin wall carotid patch versus venous patch.

    Science.gov (United States)

    Meerwaldt, R; Lansink, K W W; Blomme, A M; Fritschy, W M

    2008-07-01

    The practice of carotid endarterectomy (CEA) with patch angioplasty is more effective compared to primary closure. However, the type of patch material remains a controversy. The Fluoropassiv thin wall carotid patch is a polyester patch with an interpenetrating, nanometer-scale, solvent-applied surface modification, based on a biocompatible fluoropolymer. The present pilot study is the first clinical trial evaluating results of CEA with Fluoropassiv versus venous patch. Eighty-seven patients were randomized to 42 Fluoropassiv patching and 45 venous patching. Patients were observed by a vascular surgeon and a neurologist and scanned using duplex ultrasound with a follow-up of 2 years. No patients were lost to follow-up. Restenosis was defined as a Peak Systolic Velocity ratio >2.6, lumen reduction >50%. Perioperative stroke rate was 2.4% in the Fluoropassiv group and 8.9% in the venous group (p=0.02; 1 regressive, 4 non-regressive strokes). Multivariate analysis showed that bilateral carotid stenosis and stroke as indication for CEA were related to perioperative stroke. There was no link between perioperative stroke and patch type after correction for these factors. Patch type had no influence on operation time, clamp time, cranial nerve damage, hypertension, hematoma, infections, time to discharge, or early thromboembolic events. There were no significant differences between the Fluoropassiv and the venous group for cumulative mortality (respectively 4.4 vs 4.8%), patch occlusion (4.8 vs 2.2%), or stroke rate during 2 year follow-up (2.2 vs 2.4%). This first clinical study with the Fluoropassiv thin wall carotid patch showed no enhanced thrombogenicity compared to a venous patch. The Fluoropassiv patch is not related to a higher rate of postoperative bleeding events either.

  15. A notch-wire composite antenna for polarization diversity reception

    OpenAIRE

    Kuga, Nobuhiro; Arai, H; Goto, N

    1998-01-01

    This paper presents a notch-wire composite antenna for polarization diversity reception in an indoor base-station system, A three-notched disk antenna and a wire antenna are proposed as component antennas for the horizontal and the vertical polarization, respectively. These component antennas are unified as a single composite diversity antenna by mounting the wire antenna on the notched disk. Antenna characteristics are calculated using the method of moments (MoM) with wire grid models and ex...

  16. Compact Low Frequency Radio Antenna

    Science.gov (United States)

    Punnoose, Ratish J.

    2008-11-11

    An antenna is disclosed that comprises a pair of conductive, orthogonal arches and a pair of conductive annular sector plates, wherein adjacent legs of each arch are fastened to one of the annular sector plates and the opposite adjacent pair of legs is fastened to the remaining annular sector plate. The entire antenna structure is spaced apart from a conductive ground plane by a thin dielectric medium. The antenna is driven by a feed conduit passing through the conductive ground plane and dielectric medium and attached to one of the annular sector plates, wherein the two orthogonal arched act as a pair of crossed dipole elements. This arrangement of elements provides a radiation pattern that is largely omni-directional above the horizon.

  17. Characterization of biconical transmitting antennas

    Science.gov (United States)

    Grimes, Dale M.; Badii, Vahid; Tomiyama, Ken

    1991-01-01

    We have obtained a general, numerical solution of an ideal biconical transmitting antenna, with arbitrary arm length and conic angle. The solution evaluates the field coefficients associated with the electric multipolar expansion terms both within the antenna region and external to it; the set must necessarily be truncated, and we truncate our set with 16 terms. From the field coefficients we obtain surface current and charge densities resulting from a normalized input current, for several antennas. We evaluate resonant frequencies versus cone angle for the first three resonances. Using a normalized input voltage, we obtain the complex power at all radii; conservation of energy, in turn, permits us to solve for the reactive energy of the field per unit radius.

  18. Biogenic Amines in Insect Antennae

    Directory of Open Access Journals (Sweden)

    Marianna I. Zhukovskaya

    2017-06-01

    Full Text Available Insect antenna is a multisensory organ, each modality of which can be modulated by biogenic amines. Octopamine (OA and its metabolic precursor tyramine (TA affect activity of antennal olfactory receptor neurons. There is some evidence that dopamine (DA modulates gustatory neurons. Serotonin can serve as a neurotransmitter in some afferent mechanosensory neurons and both as a neurotransmitter and neurohormone in efferent fibers targeted at the antennal vessel and mechanosensory organs. As a neurohormone, serotonin affects the generation of the transepithelial potential by sensillar accessory cells. Other possible targets of biogenic amines in insect antennae are hygro- and thermosensory neurons and epithelial cells. We suggest that the insect antenna is partially autonomous in the sense that biologically active substances entering its hemolymph may exert their effects and be cleared from this compartment without affecting other body parts.

  19. Electrostatic Evaluation of the ARES I FTS Antenna Materials

    Science.gov (United States)

    Hogue, Michael D.; Calle, Carlos I.

    2010-01-01

    windshield periodically depleted any charge accumulated. The configuration of the Ares I antenna assembly does not include any exposed metals in the vicinity and the windshield data could not be used. Since the windshield sensor data was unusable, we decided that the Patch 2 location would provide us with a rough approximation to the Ares I antenna configuration and would give us an indication of the possible charging levels that would develop. This was the data that we used in this study. Whether these charging levels would be of the same order of magnitude as the actual charges developed by the Ares I traversing a cloud with ice particles is at this point unknown. An actual experimental test, requiring the acquisition of additional instrumentation, is strongly advised before a final recommendation can be formulated regarding the safe levels of electrostatic charging on the antenna housing. Thus the results of this study should be considered to be preliminary.

  20. Mode-matching for Optical Antennas

    CERN Document Server

    Feichtner, Thorsten; Hecht, Bert

    2016-01-01

    The emission rate of a point dipole can be strongly increased in presence of a well-designed optical antenna. Yet, optical antenna design is largely based on radio-frequency rules, ignoring e.g.~ohmic losses and non-negligible field penetration in metals at optical frequencies. Here we combine reciprocity and Poynting's theorem to derive a set of optical-frequency antenna design rules for benchmarking and optimizing the performance of optical antennas driven by single quantum emitters. Based on these findings a novel plasmonic cavity antenna design is presented exhibiting a considerably improved performance compared to a reference two-wire antenna. Our work will be useful for the design of high-performance optical antennas and nanoresonators for diverse applications ranging from quantum optics to antenna-enhanced single-emitter spectroscopy and sensing.

  1. VLBI Antenna Calibration via GPS Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to investigate and develop an inexpensive system to determine: 1)VLBI antenna properties such as axis-offset, non-intersection of axis and antenna...

  2. Application of the SWE-to-PWE antenna diagnostics technique to an offset reflector antenna

    DEFF Research Database (Denmark)

    Cappellin, Cecilia; Frandsen, Aksel; Breinbjerg, Olav

    2008-01-01

    Electrical and mechanical errors in an antenna may seriously affect the antenna's performance. Although their presence is usually detected by anomalies in the antenna's far-field pattern, their identification is normally possible only through an analysis of the antenna's extreme near field...

  3. Design considerations for low antenna correlation and mutual coupling reduction in multi antenna terminals

    DEFF Research Database (Denmark)

    Thaysen, Jesper; Jakobsen, Kaj Bjarne

    2007-01-01

    The influence of mutual coupling on the envelope correlation between two identical planar inverted F-antennas (PIFA) are investigated. The capacity of a multiple-input multiple-output (MIMO) antenna system strongly depends on the correlation between the antennas. By placing two antennas in a fixe...

  4. Accurate determination of antenna directivity

    DEFF Research Database (Denmark)

    Dich, Mikael

    1997-01-01

    The derivation of a formula for accurate estimation of the total radiated power from a transmitting antenna for which the radiated power density is known in a finite number of points on the far-field sphere is presented. The main application of the formula is determination of directivity from power......-pattern measurements. The derivation is based on the theory of spherical wave expansion of electromagnetic fields, which also establishes a simple criterion for the required number of samples of the power density. An array antenna consisting of Hertzian dipoles is used to test the accuracy and rate of convergence...

  5. Mobile Phone Antenna Performance 2016

    DEFF Research Database (Denmark)

    Pedersen, Gert F.

    This study investigates the antenna performance of a number of mobile phones widely used in the Nordic Countries. The study is supported by the Nordic Council of Ministers. The antenna performance of the phones is vital for the phones ability to ensure radio coverage in low signal situations....... The study is based on the mobile systems in the Nordic mobile networks and on both speech and data services. The selected phone models are among the most popular new phones at the time of this study....

  6. 47 CFR 73.685 - Transmitter location and antenna system.

    Science.gov (United States)

    2010-10-01

    ... antenna system. In the case of a composite antenna composed of two or more individual antennas, this means that the patterns for the composite antenna, not the patterns for each of the individual antennas, must... 47 Telecommunication 4 2010-10-01 2010-10-01 false Transmitter location and antenna system. 73.685...

  7. 47 CFR 73.6025 - Antenna system and station location.

    Science.gov (United States)

    2010-10-01

    ..., including the manufacturer and model number of the proposed directional antenna. In the case of a composite antenna composed of two or more individual antennas, the antenna should be described as a “composite... composite antenna composed of two or more individual antennas, this means that the patterns for the...

  8. Shallow ATRIS Seafloor Images - West Turtle Shoal Patch Reef, Rawa PatchReef, Dustan Rocks Patch Reef, and Thor Patch Reef, Florida, 2011

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Underwater digital images, single-beam bathymetry, and global-positioning system (GPS) data were collected September 29-30, 2011 around Dustan Rocks Patch Reef, Thor...

  9. Ethinyl Estradiol and Norelgestromin Transdermal Patch

    Science.gov (United States)

    ... but it does not prevent the spread of human immunodeficiency virus (HIV; the virus that causes acquired ... contraceptive patch may increase the risk of developing endometrial and breast cancer, gallbladder disease, liver tumors, heart ...

  10. Gain Estimation of Doubly Curved Reflector Antenna

    Directory of Open Access Journals (Sweden)

    V. Schejbal

    2008-09-01

    Full Text Available A simple formula of approximate gain estimation is verified for the doubly curved reflector antenna. Numerical simulations using physical optics and experimental results of the shaped-beam doubly curved reflector antenna are compared with the simple approximation of gain. That approximation could be very valuable for system engineers to accurately estimate antenna gain and coverage pattern and perform EMC calculations (estimations of interferences and susceptibilities even for the operation and out of operation frequency bands of shapedbeam antenna.

  11. Rectangular dielectric resonator antennas theory and design

    CERN Document Server

    Yaduvanshi, Rajveer S

    2016-01-01

    This book covers resonating modes inside device and gives insights into antenna design, impedance and radiation patterns. It discusses how higher-order modes generation and control impact bandwidth and antenna gain. The text covers new approaches in antenna design by investigation hybrid modes, H_Z and E_Z fields available simultaneously, and analysis and modelling on modes with practical applications in antenna design. The book will be prove useful to students, researchers and professionals alike.

  12. Estimation of complex permittivity using loop antenna

    DEFF Research Database (Denmark)

    Lenler-Eriksen, Hans-Rudolph; Meincke, Peter

    2004-01-01

    A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna.......A method for estimating the complex permittivity of materials in the vicinity of a loop antenna is proposed. The method is based on comparing measured and numerically calculated input admittances for the loop antenna....

  13. Inductively Shorted Bicone Fed Tapered Dipole Antenna

    Science.gov (United States)

    2012-05-23

    DATES COVERED 00-00-2012 to 00-00-2012 4. TITLE AND SUBTITLE Inductively Shorted Bicone Fed Tapered Dipole Antenna 5a. CONTRACT NUMBER 5b. GRANT...Attorney Docket No. 84449 1 INDUCTIVELY SHORTED BICONE FED TAPERED DIPOLE ANTENNA STATEMENT OF GOVERNMENT INTEREST [0001] The invention described...Invention [0003] The invention generally relates to RF antennas and more specifically to bicone and dipole antennas. (2) Description of the Prior Art

  14. Cylindrical Antenna Using Near Zero Index Metamaterial

    Science.gov (United States)

    2012-07-24

    about their vertical axes could also be used. These include, but are not be limited to, dipole antennas and biconical antennas . [0022] The anomalous...COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Cylindrical Antenna Using Near Zero Index Metamaterial 5a. CONTRACT NUMBER 5b. GRANT...1 Attorney Docket No. 101380 CYLINDRICAL ANTENNA USING NEAR ZERO INDEX METAMATERIAL STATEMENT OF GOVERNMENT INTEREST [0001] The invention

  15. Shielded Micro-Coplanar CRLH TL Zeroth-Order Resonator Antenna: Critical Performance Evaluation

    Directory of Open Access Journals (Sweden)

    M. Polivka

    2009-12-01

    Full Text Available The attention of this paper is focused on the four unit cell zeroth-order resonator antenna (ZORA, manufactured on a shielded micro-coplanar composite right/left-handed (CRLH transmission line structure. The antenna was designed to achieve a broadside patch-type radiation pattern. The dimensions of the antenna element follow: 15.6 x 9.35 x 3.1 mm (i.e. 0.27 x 0.16 x 0.05 λ0 at the measured zeroth-order resonance f0 = 5.14 GHz with the shielded plane of the size of 60 x 40 mm (approx. 1.0 x 0.7 λ0. The measured gain and the antenna efficiency are equal to 4.6 dBi and 48 %, respectively. The performance of the proposed ZORA is subject to critical evaluation based on the comparison with the reference quarter-wavelength patch antenna (QWPA that has the same dimensions. It has been found that ZORA provides comparable or even better parameters to those of QWPA, except of the bandwidth, which is much narrower in case of ZORA. In comparison to QWPA, the main advantage of the proposed ZORA might be then seen in the possibility to produce the entire ZORA structure by means of the integrated microstrip technology with air bridges. In contrary to it, the fabrication of the QWPA requires the use of either the foam substrate or plastic support pins or the application of ridged self-supporting metal plates.

  16. International Mapping of Antenna-Measurement Facilities

    DEFF Research Database (Denmark)

    Boccia, Luigi; Breinbjerg, Olav; Di Massa, Giuseppe

    2006-01-01

    in the field of antenna measurements. It has been established to provide the scientific and industrial community with an efficient means to improve and facilitate their research and development activities in the field of antennas. The mapping will constitute a new service for all potential users of antenna...

  17. Future Vogues in Handset Antenna Systems

    DEFF Research Database (Denmark)

    Pelosi, Mauro; Pedersen, Gert Frølund

    2011-01-01

    This paper exemplifies future trends in handset antenna systems, contextualizing their historical evolution and anticipating novel paradigms. It is shown through numerical simulations how narrow-band antennas used in transceiver separation mode can reduce the total loss in presence of the user......’s hand, improving at the same time the antenna isolation....

  18. Numerical Study of Planar GPR Antenna Measurements

    DEFF Research Database (Denmark)

    Meincke, Peter; Hansen, Thorkild

    2004-01-01

    The formulation of planar near-field measurements of GPR antennas determines the plane-wave spectra of the GPR antenna in terms of measurements obtained with a buried probe as the GPR antenna moves over a scan plane on the ground. A numerical study investigates how the formulation is affected by (1...

  19. 47 CFR 74.641 - Antenna systems.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Antenna systems. 74.641 Section 74.641... Stations § 74.641 Antenna systems. (a) For fixed stations operating above 2025 MHz, the following standards... elevation planes. (2) New periscope antenna systems will be authorized upon a certification that the...

  20. 47 CFR 78.105 - Antenna systems.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Antenna systems. 78.105 Section 78.105... SERVICE Technical Regulations § 78.105 Antenna systems. (a) For fixed stations operating in the 12.7-13.2... planes. (2) New periscope antenna systems will be authorized upon a certification that the radiation, in...