Dissertationen zum Thema „Slot antenna arrays“
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1
Voigt, Dewald. „Computational investigation of a crossed slot cavity-backed array antenna“. Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/2659.
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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2006.This thesis investigates a computational model of an electronically steered antenna array. It focuses on a simple element comprising an S-shaped, crossed, cylindrical cavity-backed slot antenna. An unusual aspect of the element is the addition of a top hat, which contributes to the low scanning ability of the array. The objective was to confirm this contribution of the top hat. During the investigation, the computation code Feko was validated for slot analysis through consideration of the basic properties of a dipole and slot and how they related to each other. Various alternative models were evaluated, before a final accurate model was modelled in Feko, to find possible equivalent models. The final model, which implemented the use of Feko as release 5, was the only one that achieved successful results. The results showed that the top hat does play an important role in the steering of the beam. The mechanism through which this occurs was identified. The results that where obtained indicated that there may be more effective elements than the cylindrical element and the identification of this is proposed as a field for further study.
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Mustafa, Incebacak. „Design Of Series-fed Printed Slot Antenna Arrays Excited By Microstrip Lines“. Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612447/index.pdf.
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Series-fed printed slot antenna arrays excited by microstrip lines are low profile, easy to manufacture, low cost structures that found use in applications that doesn&rsquot require high power levels with having advantage of easy integration with microwave front-end circuitry. In this thesis, design and analysis of microstrip line fed slot antenna arrays are investigated. First an equivalent circuit model that ignores mutual coupling effects between slots is studied. A 6-element array is designed by using this equivalent circuit model. From the measurement and electromagnetic simulation results of this array, it is concluded that mutual coupling effects should be considered in order to achieve a successful design that meets the design specifications related to the main beam direction and sidelobe levels of the antenna. Next, an improved equivalent circuit model proposed for stripline fed slot antenna arrays is studied. It is observed that, the mutual coupling effects are incorporated into the equivalent model through the utilization of active impedance concept. Finally, the design equations proposed in the improved equivalent circuit model are derived for the microstrip line fed slot antenna array structure. To demonstrate the validity and the accuracy of the derived design equations, results obtained by the proposed analysis method are compared with simulation and measurement results. It is concluded that the proposed method successfully predicts the radiation pattern of the array by including the mutual coupling effects.
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Öjefors, Erik. „Integrated Antennas : Monolithic and Hybrid Approaches“. Doctoral thesis, Uppsala University, Department of Engineering Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7142.
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This thesis considers integration of antennas and active electronics manufactured on the same substrate. The main topic is on-chip antennas for commercial silicon processes, but hybrid integration using printed circuit board technology is also addressed.
The possible use of micromachining techniques as a means of reducing substrate losses of antennas manufactured on low resistivity silicon wafers is investigated. Compact dipole, loop, and inverted-F antennas for the 20-40 GHz frequency range are designed, implemented, and characterized. The results show significantly improved antenna efficiency when micromachining is used as a post-processing step for on-chip antennas manufactured in silicon technology.
High resistivity wafers are used in a commercial silicon germanium technology to improve the efficiency of dipole antennas realized using the available circuit metal layers in the process. Monolithically integrated 24 GHz receivers with on-chip antennas are designed and evaluated with regard to antenna and system performance. No noticeable degradation of the receiver performance caused by cross talk between the antenna and the integrated circuit is observed.
For low frequency antenna arrays, such as base station antennas, hybrid integration of active devices within the antenna aperture is treated. A compact varactor based phase shifter for traveling wave antenna applications is proposed and evaluated. Electrically steerable traveling wave patch antenna arrays, with the phase shifters implemented in the same conductor layer as the radiating elements, are designed and manufactured in microstrip technology. It is experimentally verified that the radiation from the feed network and phase shifters in the proposed antenna configuration is small.
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Zivanovic, Bojana. „Series-Fed Aperture-Coupled Microstrip Antennas and Arrays“. Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4425.
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The focus of this dissertation is on the development and circuit modeling of planar series-fed, linear- and circular-polarized microstrip aperture-coupled antennas and N-element arrays operating in C-band. These arrays were designed to be used as part of airborne or land-based frequency-hopped communication systems. One of the main objectives of this work was to maintain a constant beam angle over the frequency band of operation. In order to achieve constant beam pointing versus frequency, an anti-symmetric series-fed approach using lumped-element circuit models was developed. This series feed architecture also balances the power radiated by each element in the N-element arrays.
The proposed series-fed approach was used in the development of four-element series-fed aperture-coupled arrays with 15% 10 dB impedance bandwidth centered at 5 GHz and a gain of 11.5 dB, to construct an omni-directional radiator. Omni-directional radiators with pattern frequency stability are desired in a multitude of applications; from defense in tactical communications, information gathering, and detection of signal of interest to being part of sensors in medical applications. A hexagonal assembly of six series-fed microstrip aperture-coupled four-element arrays was used to achieve the omni-directional radiation with 0.6 dB peak to peak difference across 360˚ broadside pattern and 0.6 dB gain variation at the specific azimuth angle across 15% impedance bandwidth. Given that each of these six arrays can be individually controlled, this configuration allows for individual pattern control and reconfiguration of the omni-directional pattern with increased gain at specific azimuth angles and the ability to form a directional pattern by employing a fewer number of arrays. Incorporating a beam-forming network or power distribution network is also possible.
Wide 3 dB circular polarization (CP) bandwidth was achieved without external couplers and via only a single feed with a unique Z-slot aperture-coupled microstrip antenna. A single RHCP Z-slot aperture-coupled antenna has ∼10% CP and 10 dB impedance bandwidth. The series-fed network consisting of lumped elements, open-circuited stubs and transmission lines was subsequently developed to maintain more than 5% CP and 10% 10 dB impedance bandwidth in the series-fed four-element Z-slot aperture-coupled CP array that could also be used for-omni-directional radiation.
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Zhang, Shuai. „Investigating and Enhancing Performance of Multiple Antenna Systems in Compact MIMO/Diversity Terminals“. Doctoral thesis, KTH, Elektroteknisk teori och konstruktion, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-116402.
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Today, owners of small communicating device are interested in transmitting or receiving various multimedia data. By increasing the number of antennas at the transmitter and/or the receiver side of the wireless link, the diversity/Multiple-Input Multiple-Output (MIMO) techniques can increase wireless channel capacity without the need for additional power or spectrum in rich scattering environments. However, due to the limited space of small mobile devices, the correlation coefficients between MIMO antenna elements are very high and the total efficiencies of MIMO elements degrade severely. Furthermore, the human body causes high losses on electromagnetic wave. During the applications, the presence of users may result in the significant reduction of the antenna total efficiencies and highly affects the correlations of MIMO antenna systems. The aims of this thesis are to investigate and enhance the MIMO/diversity performance of multiple antenna systems in the free space and the presence of users. The background and theory of multiple antenna systems are introduced briefly first. Several figures of merits are provided and discussed to evaluate the multiple antenna systems. The decoupling techniques are investigated in the multiple antenna systems operating at the higher frequencies (above 1.7 GHz) and with high radiation efficiency. The single, dual and wide band isolation enhancements are realized through the half-wavelength decoupling slot, quarter-wavelength decoupling slot with T-shaped impedance transformer, tree-like parasitic element with multiple resonances, as well as the different polarizations and radiation patterns of multiple antennas. In the lower bands (lower than 960 MHz), due to the low radiation efficiency and strong chassis mode, the work mainly focused on how to directly reduce the correlations and enlarge the total efficiency. A new mode of mutual scattering mode is introduced. By increasing the Q factors, the radiation patterns of multiple antennas are separated automatically to reduce the correlations. With the inter-element distance larger than a certain distance, a higher Q factor also improved the total efficiency apart from the low correlation. A wideband LTE MIMO antenna with multiple resonances is proposed in mobile terminals. The high Q factors required for the low correlation and high efficiencies in mutual scattering mode is reduced with another mode of diagonal antenna-chassis mode. Hence, the bandwidth of wideband LTE MIMO antenna with multiple resonances mentioned above can be further enlarged while maintaining the good MIMO/diversity performance. The user effects are studied in different MIMO antenna types, chassis lengths, frequencies, port phases and operating modes. Utilizing these usefully information, an adaptive quad-element MAS has been proposed to reduce the user effects and the some geranial rules not limited to the designed MAS have also been given.QC 20130121
EU Erasmus Mundus External Cooperation Window TANDEM
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Farias, Roger Lorenzoni. „Antenas de microfita dupla-faixa para aplicações em estações rádio-base de telefonia móvel celular“. Universidade Federal do Pampa, 2014. http://dspace.unipampa.edu.br:8080/xmlui/handle/riu/250.
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Neste trabalho, são apresentadas diferentes técnicas que possibilitam a obtenção de característica dupla-faixa para antenas de microfita especificamente voltadas para aplicações em estações rádio-base de telefonia móvel celular no Brasil. As faixas de frequência de interesse encontram-se no intervalo de 0,824 GHz a 0,960 GHz para a banda inferior e 1,710 GHz a 2,165 GHz para a banda superior. Além de atender as especificações técnicas de faixa de passagem, devem ser atendidos os requisitos de coeficiente de reflexão, polarização, ganho, largura de feixe de irradiação e impedância de entrada na faixa de interesse. Primeiramente, para obtenção de antenas de microfita com característica multibanda, descreve-se a técnica em que são dispostas fendas nos elementos irradiadores, onde são estudadas três topologias de antenas, explicando-se os princípios de funcionamento e destacando-se as particularidades de cada geometria. As três antenas são analisadas e projetadas com o auxílio do software comercial de simulação eletromagnética Ansoft Designer ® , visando levantar os parâmetros elétricos através de diversos estudos paramétricos em função da variação das dimensões das antenas para compreender melhor o comportamento de cada estrutura simulada. A antena com elemento irradiador em forma de H foi a única que cumpriu os requisitos em termos de faixa de passagem e diagramas de irradiação para operação em sistemas de telefonia móvel celular. No entanto, esta geometria resultou em dimensões físicas consideráveis, pois necessita da utilização de múltiplas camadas dielétricas, acarretando em um protótipo de volume considerável e de elevado custo de produção. Outra técnica estudada foi a sobreposição de elementos irradiadores, porém a mesma não é investigada detalhadamente em função de o custo de produção da antena ser mais elevado em comparação a topologias coplanares. Em seguida, uma técnica com irradiadores em fenda anelar e dupla alimentação é proposta. A antena é projetada considerando-se duas portas independentes, uma para cada banda de operação, formando uma antena de dois acessos altamente isolados. Simulações com o software HFSS TM mostraram que é possível satisfazer as especificações para operação em estações rádio-base de telefonia móvel celular. A grande vantagem desta estrutura é a possibilidade de utilização de apenas um laminado de micro-ondas, o que reduz o custo de produção em comparação a outras topologias. Protótipos foram construídos e caracterizados experimentalmente para validar o projeto realizado no simulador eletromagnético. Constatou-se a presença de discrepâncias entre os resultados simulados e medidos. Após simulações paramétricas, verificou-se que o processo de construção alterou a geometria do protótipo em relação ao modelo de simulação. Após a inclusão das imperfeições do processo construtivo no modelo, foi possível estimar as mudanças necessárias no protótipo. Após os devidos ajustes realizados em bancada, os resultados medidos exibiram boa concordância com a previsão teórica. Por fim, realizou-se um estudo de viabilidade da utilização da antena em fenda anelar dupla-faixa para composição de uma rede de antenas para estações rádio-base. A análise teve como principal objetivo verificar a possibilidade de síntese de diagramas de irradiação em forma de cossecante ao quadrado em ambas as bandas de operação. Excelente resultado foi obtido para a banda inferior, enquanto que algumas limitações foram encontradas na banda superior.
In this work we present different techniques for achieving the dual-band feature for microstrip antennas aimed to be used in the mobile communication base stations of Brazil. The focused frequency range for lower and higher bands is in the 0.824-0.960 GHz and 1.710-2.165 GHz intervals, respectively. In addition to comply with the technical specifications, the solution is also supposed to meet the requirements of return loss, polarization, gain, beamwidth radiation and input impedance in the focused frequency range. Initially, in order to obtain microstrip antennas with dual-band characteristic, we describe the technique in which slots are placed in the irradiating elements. Three antenna topologies are analyzed in its operation principles, emphasizing the particularities of each geometry. The antennas are designed with support of Ansoft Designer ® , a commercial software that simulates electromagnetic features, in order to find out the electrical parameters through parametric studies and to better understand the behavior of each simulated structure. These studies considered the variation in the dimensions of antennas. The H-shaped microstrip antenna was the only one able to fulfill the requirements of bandwidth and irradiation diagrams for operation in mobile communication. However, this geometry originated an antenna of considerable physical dimensions, because it requires the use of multiple dielectric layers, resulting in a prototype of considerable volume and high production cost. Another technique studied was the stacking of irradiating elements. However it isn’t investigated in detail because of the production cost of the antenna, which is higher than the ones of coplanar topologies. After all that, we propose a technique based in annular-slot antennas and double feed. The antenna is designed considering two independent ports, one for each band of operation, making an antenna of two highly insulated accesses. Simulations by the HFSS TM software have shown that it’s possible to comply with the specifications for operation in base stations of the mobile communication. The biggest advantage of this structure over other topologies is that it may be made of only one microwave laminate, reducing the production cost. Prototypes were built and measured to validate the design in the electromagnetic simulator. It was noted the discrepancies between the simulated and measured results. After running parametric simulations, we found out that the building process of the prototype changed the geometry of the simulation model. We included these imperfections in the model and it was possible to estimate the necessary changes in the prototype. After inclusion of the adjustments, the measured results behaved just alike the theoretical prediction. Finally, we’ve done a feasibility study on the use of the dual-band annular slot antenna for making an array of antennas for base stations. The study aimed to verify the suitability of synthetizing squared-cosecant shaped pattern in both operation bands. We got excellent results for the lower band, although some limitations were found for the higher band.
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Ng, Kwong-Tai. „Admittance properties of a slot array with parasitic wire arrays in a stratified medium /“. The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487259580262744.
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Lundin, Andreas. „Interference and Energy Conservation in Phased Antenna Arrays and Young’s Double Slit Experiment“. Thesis, Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-188035.
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The interest in creating and detecting electromagnetic waves carryingangular momentum in such a way that they form helical wavefronts,so called "twisted light'', has increased in recent decades.One possible way of generating such waves at radio frequenciesis to use a circular phased antenna array, where a larger relativephasing of the antenna elements corresponds to more twist of thewavefront per wavelength.However, analytical computations of the radiated power, and in turn theamountof emitted angular momentum, displays a quite rapid decrease with increasedphasing. This decrease in intensity may cause problems when alarge range of twisting is desired; for instance, as a means to encodeand transmit information. We have found that the decrease in radiatedpower does not haveany explicit relation to the beam being endowed with angular momentum.Instead, the decrease in emitted power can be explained byelectromagnetic couplingof the antenna elements in the array and that energy conservationholds, because an equal decrease in power is seen at the input of the array.We also show that a similar discrepancy is seen between the incomingand the total diffracted power in Young's classic double slit experiment,which, having only two slits, cannot provide any twisted light.The source of that discrepancy should be of a different origin.Although an explanation in terms of surface plasmons was recently givenin the literature, that is only applicable to metal screens. A general explanation of the problem therefore remains to be found.
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Mcknight, James W. „A cavity-backed coplanar waveguide slot antenna array“. [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0003299.
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Grbic, Anthony. „A novel leaky millimeter-wave linear slot antenna array“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58792.pdf.
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McCann, John Forrest. „On the design of large bandwidth arrays of slot elements with wide scan angle capabilities“. Connect to resource, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1209590321.
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Dogan, Doganay. „Dual Polarized Slotted Waveguide Array Antenna“. Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613016/index.pdf.
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An X band dual polarized slotted waveguide antenna array is designed with very high polarization purity for both horizontal and vertical polarizations. Horizontally polarized radiators are designed using a novel non-inclined edge wall slots whereas the vertically polarized slots are implemented using broad wall slots opened on baffled single ridge rectangular waveguides. Electromagnetic model based on an infinite array unit cell approach is introduced to characterize the slots used in the array. 20 by 10 element planar array of these slots is manufactured and radiation fields are measured. The measurement results of this array are in very good accordance with the simulation results. The dual polarized antenna possesses a low sidelobe level of -35 dB and is able to scan a sector of ±35 degrees in elevation. It also has a usable bandwidth of 600 MHz.
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Paryani, Rajesh. „DESIGN OF A WIDEBAND DUAL-POLARIZED CAVITY BACKED SLOT ANTENNA“. Doctoral diss., University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2832.
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A new technique for designing wideband dual-polarized cavity-backed slot antennas is presented. The structure is in the form of a double-resonant, dual-polarized slot antenna backed by a shallow substrate integrated cavity with a depth of approximately one tenth the free space wavelength. The presence of the cavity behind the slot enhances the antenna s directivity and reduces the possibility of surface wave propagation in the antenna substrate when the element is used in an array environment. Moreover, the dual-polarized nature of this radiating element may be exploited to synthesize any desired polarization (vertical, horizontal, RHCP, or LHCP). The double-resonant behavior observed in this substrate-integrated cavity-backed slot antenna (SICBSA) is utilized to enhance its bandwidth compared to a typical cavity-backed slot antenna. A prototype of the proposed antenna is fabricated and tested. Measurement results indicate that a bandwidth of 19%, an average gain of 5.3 dB, and a wideband differential isolation of 30 dB can be achieved using this technique. The principles of operation along with the measurement results of the fabricated prototype are presented and discussed in this dissertation. The SICBSA is investigated as a candidate for use as an array element. A uniform two element phased array is demonstrated to locate the main beam from boresight to thirty degrees. The potential effects of mutual coupling and surface wave propagation are considered and analyzed.Ph.D.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering PhD
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Noghanian, Sima. „Field solution for dielectric and ring loaded annular slot array antennas“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ62661.pdf.
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Eshrah, Islam A. „Waveguide and metaguide excitation of dielectric resonator antenna arrays using slots and probes /“. Full text available from ProQuest UM Digital Dissertations, 2005. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1267222711&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1184857149&clientId=22256.
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Meng, Xiangjun. „A synthesis technique for radial line slot array antennas with isoflux radiation patterns“. Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28325.
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In this thesis the possibility of using radial line slot array (RLSA) antennas to provide low profile isoflux radiation patterns suitable for use as circularly-polarized tracking, telemetry & command (TT&C) antennas on low Earth orbit (LEO) satellites is investigated. The RLSA antenna elements are slot pairs located on concentric circles on the top plate of a radial waveguide. Conventional synthesis techniques cannot be used due to the fact that the RLSA antenna is a non-uniformly spaced array, the elements do not all have the same orientation, and the excitation amplitudes and phases are linked to the actual physical location of a particular slot pair. A technique is therefore developed for synthesizing such an RLSA antenna.
Keywords: Antennas, Radial Line Slot Antennas, Isoflux Radiation Patterns
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Abdel, Rahman Mohamed. „ANTENNA-COUPLED TUNNEL DIODES FOR DUAL-BAND MILLIMETER-WAVE/INFRARED F“. Doctoral diss., University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2597.
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The infrared and millimeter-wave portions of the spectrum both have their advantages for development of imaging systems. Because of the difference in wavelengths, infrared imagers offer inherently high resolution, while millimeter-wave systems have better penetration through atmospheric aerosols such as fog and smoke. Shared-aperture imaging systems employing a common focal-plane array that responds to both wavebands are desirable from the viewpoint of overall size and weight. We have developed antenna-coupled sensors that respond simultaneously at 30 THz and at 94 GHz, utilizing electron-beam lithography. Slot-antenna designs were found to be particularly suitable for coupling radiation into metal-oxide-metal (MOM) tunnel diodes at both frequencies. The MOM diodes are fabricated in a layered structure of Ni-NiO-Ni, and act as rectifying contacts. With contact areas as low as 120 nm × 120 nm, these diodes have time constants commensurate with rectification at frequencies across the desired millimeter-wave and infrared bands. One challenge in the development of true focal-plane array imagers across this factor-of-300 bandwidth is that the optimum spatial sampling interval on the focal plane is different in both bands. We have demonstrated a focal plane with interleaved infrared and millimeter-wave sensors by fabricating infrared antennas in the ground plane of the millimeter-wave antenna. Measured performance data in both bands are presented for individual antenna-coupled sensors as well as for devices in the dual-band focal-plane-array format.Ph.D.
Department of Electrical and Computer Engineering
Engineering and Computer Science
Electrical Engineering
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Caswell, Eric D. „Design and Analysis of Star Spiral with Application to Wideband Arrays with Variable Element Sizes“. Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/25963.
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This dissertation details the development of the star spiral antenna and demonstrates the advantages of the star spiral when used in a wideband array with variable element sizes. The wideband array with variable element sizes (WAVES) is a multi-octave array that uses different sized circular Archimedean spirals for each octave of frequency coverage. A two-octave WAVES array has been presented in the literature, but a gap in the two-octave frequency coverage exists along the principal axes. The star spiral antenna was developed to eliminate the performance gap in the WAVES array. The star spiral is a type of slow-wave spiral that also offers array-packing advantages, particularly for the WAVES array. The size reduction that can be achieved with the star spiral is comparable to that of the square spiral, but the star spiral is much more efficient in terms of its expected size reduction compared to its circumference. The far-field patterns, gain, and scan performance of the star spiral are similar to that of the circular Archimedean spiral. The use of the star spiral to eliminate the performance gap in a WAVES array of circular Archimedean spirals is detailed. Furthermore, a three-octave WAVES array of star spirals is built and measured, and the scan performance of the array is investigated via simulation.Ph. D.
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Guerra, Leonard. „IEEE 802.11b wireless LAN sensor system and antenna design“. [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001713.
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Tong, Chin Hong Matthew. „System study and design of broad-band U-Slot microstrip patch antennas for aperstructures and opportunistic arrays“. Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Dec%5FTong.pdf.
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Thesis (M.S. in Combat Systems Technology)--Naval Postgraduate School, December 2005.Thesis Advisor(s): David C. Jenn, Donald L. Walters. Includes bibliographical references (p.83-85). Also available online.
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Almhmadi, Raed Ali M. „Optical True Time Delay Device for mm-Wave Antenna Array Beamforming“. The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1566073503380698.
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Sedláček, Petr. „Štěrbinová anténní řada na bázi vlnovodu integrovaného do substrátu“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219844.
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The Master’s Thesis deals with the design of slot antenna array based on the substrate integrated waveguide (SIW). Various supply methods are described and the design procedure is approached. The antenna array was designed for Wi-Fi band of 5 GHz in the Ansoft HFSS simulation software. The optimalized parameters are impedance bandwidth (low reflection coefficient at antenna input in the desired frequency band) and the gain (the maximum value). As the result of the work 3 antenna arrays based on the substrate integrated waveguide are designed and fabricated: antenna arrays 2x1, 2x2 and antenna array 2x2 supplemented with housing for outdoor use. The work also contains a comparison of simulated and measured parameters of antennas.
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Qassim, K. A. S. „Optimisation of focal plane arrays for microwave imaging : printed Yagi, dielectric rod and constant width slot antennas are investigated and optimised for close stacking in focal plane arrays intended for microwave imaging“. Thesis, University of Bradford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320761.
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Štumpf, Martin. „Pulzní elektromagnetické záření štěrbinových antén“. Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-233527.
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Jednoduché dvojrozměrné anténní zářiče, které slouží jako stavební bloky anténních polí, jsou analyticky analyzovány v časové oblasti. Jako hlavní nástroj pro analýzu je použita Cagniard-DeHoopova metoda. Je ukázáno, že zvolený přístup umožňuje získat přesné vzorce v časové oblasti v uzavřeném tvaru, které jasně demonstrují vliv vstupních parametrů a objasňují fyzikální podstatu pulsního elektromagnetického vyzařování. Dané numerické výsledky ilustrují důležité aspekty pulsního elektromagnetického záření v rozličných konfiguracích problémů. Získané výsledky jsou užitečné pro efektivní návrh anténních polí, které jsou buzeny pulsními signály.
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Špůrek, Jan. „Textilní štěrbinová anténa“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242116.
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This diploma thesis is focused on design of various antenna structures, based on slot antennas, created in the wider wall of a rectangular-shaped waveguide. As the substrate, it is used a 3D textile material, while its properties are examined. They were designed structures, that operate with linear and circular polarization, and other related structures, that are used for feeding and power division. Structures are designed to operate at central frequency of 8 GHz and its vicinity.
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Miřácký, Jan. „Návrh anténní jednotky přístupového bodu pro off-body komunikaci v ISM pásmu 61 GHz“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221250.
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The Master´s thesis deals with the theoretical design, practical numerical analyses and optimalization of disc-like antenna and disc-like slot antenna. The antennas have relative omnidirectional radiation characteristics in the horizontal plane, respectively in the vertical plane. Antennas exploit the substrate integrated waveguide technology. The antennas themselves are designed for the purpose of making the antenna array that will be work as an antenna unit for access point. The antennas are manufactured and experimentally verified. The program CST Microwave Studio is used for simulation in the thesis.
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Cheng, Shi. „Integrated Antenna Solutions for Wireless Sensor and Millimeter-Wave Systems“. Doctoral thesis, Uppsala universitet, Mikrovågs- och terahertzteknik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-111197.
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This thesis presents various integrated antenna solutions for different types of systems and applications, e.g. wireless sensors, broadband handsets, advanced base stations, MEMS-based reconfigurable front-ends, automotive anti-collision radars, and large area electronics. For wireless sensor applications, a T-matched dipole is proposed and integrated in an electrically small body-worn sensor node. Measurement techniques are developed to characterize the port impedance and radiation properties. Possibilities and limitations of the planar inverted cone antenna (PICA) for small handsets are studied experimentally. Printed slot-type and folded PICAs are demonstrated for UWB handheld terminals. Both monolithic and hybrid integration are applied for electrically steerable array antennas. Compact phase shifters within a traveling wave array antenna architecture, on single layer substrate, is investigated for the first time. Radio frequency MEMS switches are utilized to improve the performance of reconfigurable antennas at higher frequencies. Using monolithic integration, a 20 GHz switched beam antenna based on MEMS switches is implemented and evaluated. Compared to similar work published previously, complete experimental results are here for the first time reported. Moreover, a hybrid approach is used for a 24 GHz switched beam traveling wave array antenna. A MEMS router is fabricated on silicon substrate for switching two array antennas on a LTCC chip. A concept of nano-wire based substrate integrated waveguides (SIW) is proposed for millimeter-wave applications. Antenna prototypes based on this concept are successfully demonstrated for automotive radar applications. W-band body-worn nonlinear harmonic radar reflectors are proposed as a means to improve automotive radar functionality. Passive, semi-passive and active nonlinear reflectors consisting of array antennas and nonlinear circuitry on flex foils are investigated. A new stretchable RF electronics concept for large area electronics is demonstrated. It incorporates liquid metal into microstructured elastic channels. The prototypes exhibit high stretchability, foldability, and twistability, with maintained electrical properties.wisenet
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Alfonso, Alós Esperanza. „New quasi-TEM waveguides using artificial surfaces and their application to antennas and circuits“. Doctoral thesis, Universitat Politècnica de València, 2011. http://hdl.handle.net/10251/11073.
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Research interest: In recent years we have seen the emergence of
commercial applications at high frequencies, such as the top part of
the microwave band and the millimeter and sub-millimeter bands,
and it is expected a big increase in the coming years. This growing
demand requires a rapid development of low-cost technology
with good performance at these frequencies, where common technologies,
such as microstrip and standard waveguides, have some
shortcomings. In particular, existing solutions for high-gain planar
scanning antennas at these frequencies su er from the disadvantages
of these technologies giving rise to high-cost products not suitable
for high volume production.
Objectives: The main objective of this thesis is to study the feasibility
of a new proposal to improve existing solutions to date for
low-cost high-gain planar scanning antennas at high frequencies.
This overall objective has resulted in another central objective of
this thesis, which is the research of new quasi-TEM waveguides that
are more appropriate than current technologies for the realization
of circuits and components at these frequency bands. These guided
solutions make use of periodic or arti cial surfaces in order to con-
ne and channel the elds within these waveguides.
Methodology: The work follows a logical sequence of speci c tasks
aimed at achieving the main objective of this thesis. Chapter 2
presents the proposed guiding solution and shows its performance
numerical and experimentally. The optimized design of high-gain
antennas based on waveguide slot arrays requires the development
of e cient ad-hoc codes. The implementation and validation of this
code is presented in Chapter 3, where a new method for the analysis
of corrugated surfaces is proposed, and in Chapter 4, which extends
this code to the analysis of waveguide slot arrays. The process
design and optimization of a two-dimensional array is described
in Chapter 5, where a preliminary experimental validation is also
described. Moreover, the proposed guiding solution has inspired
the development of a new guiding technology of wider bandwidth
and more versatile for the realization of circuits and components at
high frequencies. Chapter 6 presents the contributions to the study
of this technology and its application to the design of circuits.Alfonso Alós, E. (2011). New quasi-TEM waveguides using artificial surfaces and their application to antennas and circuits [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11073
Palancia
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Weigel, Filip. „Rekonfigurovatelná štěrbinová anténní řada“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242136.
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This master's thesis deals with the basic principles of slot antennas. Models of antennas were simulated in a selected electromagnetic simulator CST MICROWAVE STUDIO (CST MWS). There are several models of slot antennas which are optimized for communication in the car at a frequency 8 GHz.
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ZHENG, RUI-GING, und 鄭瑞清. „Slot-coupled microstrip antenna arrays“. Thesis, 1989. http://ndltd.ncl.edu.tw/handle/19959493304377062070.
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Jeng, Jing-Feng, und 鄭謹鋒. „Design of Tapered Slot Antenna Arrays“. Thesis, 1999. http://ndltd.ncl.edu.tw/handle/65710230559578687583.
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碩士國立交通大學
電信工程系
88
The tapered slot antenna arrays were integrated the single element of the tapered slot antenna (TSA) on E- or H-plane. Therefore, the characteristics of the TSA will be made a review and discussed. The measured results of the single element of TSA with corrugated edges will be presented and compared with the single element of TSA to realize the effects of corrugated edges. We will introduce the bilateral fin-line fed linear tapered slot antenna (LTSA) and comparing the measured results with the unilateral fin-line fed LTSA to design a TSA which has high gain and low cross polarization level. Finally, the LTSA arrays of two different feeding structures will be proposed. The design procedures and the characteristics of the LTSA arrays will be discussed.
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Del, Río Del Río David. „Characterization of log periodic folded slot antenna array /“. 2005. http://grad.uprm.edu/tesis/delriodelrio.pdf.
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Wood, Ian. „Linear tapered slot antenna for imaging arrays“. Thesis, 2007. http://hdl.handle.net/1828/283.
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A prototype imaging array utilizing tapered slot antenna elements is investigated for potential use in radio astronomy. The design utilizes a previously reported substrate integrated waveguide style feed for the antenna element. The reported behavior of a tapered slot antenna is reproduced within CST Microwave Studio simulator, and the design parameters in the previous design were ported to a higher frequency and adjusted to increase directivity. Approximately symmetric 3 dB beamwidths are achieved in the simulator. Array simulation is limited in scope; a prototype, sixteen element planar array was fabricated and measured. Mutual coupling effects between elements cause adverse radiation performance compared to simulated predictions. Array performance is improved by using an alternate array configuration that introduced electrical boundaries between adjacent elements. Cross-polarization performance and array element spacing remain significant challenges to the antenna and feed technology for use in radio astronomy.
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Kim, Young-Sik. „Linearly tapered slot antenna arrays for multibeam systems“. 1988. https://scholarworks.umass.edu/dissertations/AAI8822670.
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A linearly tapered slot antenna (LTSA) acting as a single element and as an array element has been experimentally investigated. Although the antenna, used either for a single element or for 5 x 5 multibeam array elements, had the gain loss which was estimated as about one quarter of the total radiated power, due to cross-polarized radiation, the antenna yielded wide bandwidth, high gain, and high aperture efficiency. A new method to calculate the directivity and efficiency was developed, which is based on integration of co- and cross-polarized patterns in three planes. The directivity and efficiency was over-estimated when evaluated from co-polarized radiation patterns in the E/H-planes. The estimated aperture efficiency of an LTSA array used with a paraboloid, was 40-50% for an element spacing which resulted in cross-over levels of the beams about -3dB. This efficiency compares favorably with 60% for an optimum (cos)$\sp{q}$ feed pattern, at the same spacing. An equally spaced phased array with a slotline power combiner as a feed network was investigated, and the results agreed well with theoretical calculations.
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Tseng, Chen-Chia, und 曾振家. „Design of the Antipodal Linearly Tapered Slot Antenna Arrays“. Thesis, 2002. http://ndltd.ncl.edu.tw/handle/29271273695321060749.
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碩士國立交通大學
電信工程系
90
In this thesis, design of an 8×8 Antipodal Linearly-Tapered Slot Antenna array (ALTSA array) for Ka band (26.5~35 GHz) is presented. The array is power divided by an 1×8 H-plane rectangular waveguide power divider in H-plane, by an 1×8 balanced microstrip line power divider in E-plane. Besides, we adopted antipodal fin line to construct the transition between waveguide and microstrip line. The center frequency of the array is designed to be 30 GHz, and the gain is about 30 dBi. Simulation of most of our design is mainly by Ansoft/HFSS 8.0 and some by Ansoft/Ensemble 8.0.
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鄭世杰. „Design of 5GHz antipodal linearly-tapered planar slot antenna arrays“. Thesis, 2003. http://ndltd.ncl.edu.tw/handle/93159687242115560801.
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碩士樹德科技大學
電腦與通訊研究所
91
This thesis presented the design of 5GHz antipodal linearly-tapered slot antenna (ALTSA) array using three-dimensional (3-D) finite element method (FEM). Both of single element and arrays of ALTSA with different parameters are studied. The printed ALTSA arrays have been implemented by using the FR-4 PCB substrate. For the single ALTSA, good agreements between simulation and measurement on input VSWR (about 1.3) and antenna directivity (about 12dBi) are achieved in the range of 5~6 GHz. For the ALTSA arrays, it could be found that, although with narrower HPBW, the directivity is slightly greater when the number of antenna element increases. But it could only be operated effectively in a narrower range of frequency (5.7~5.85GHz). There exists a trade-offs between antenna gain and bandwidth. The designed single element and arrays of ALTSA can be used for 5GHz communication system , such as the local point to point transmission between the buildings.
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Alibakhshikenari, M., B. S. Virdee, C. H. See, Raed A. Abd-Alhameed und E. Limiti. „High performance on-chip array antenna based on metasurface feeding structure for terahertz integrated circuits“. 2019. http://hdl.handle.net/10454/18118.
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YesIn this letter a novel on-chip array antenna is investigated which is based on CMOS 20μm Silicon technology for operation over 0.6-0.65 THz. The proposed array structure is constructed on three layers composed of Silicon-Ground-Silicon layers. Two antennas are implemented on the top layer, where each antenna is constituted from three sub-antennas. The sub-antennas are constructed from interconnected dual-rings. Also, the sub-antennas are interconnected to each other. This approach enhances the aperture of the array. Surface waves and substrate losses in the structure are suppressed with metallic via-holes implemented between the radiation elements. To excite the structure, a novel feeding mechanism is used comprising open-circuited microstrip lines that couple electromagnetic energy from the bottom layer to the antennas on the top-layer through metasurface slot-lines in the middle ground-plane layer. The results show the proposed on-chip antenna array has an average radiation gain, efficiency, and isolation of 7.62 dBi, 32.67%, and -30 dB, respectively.
H2020-MSCA-ITN-2016 SECRET-722424 and the financial support from the UK Engineering and Physical Sciences Research Council (EPSRC) under grant EP/E0/22936/1
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Chen, Shang-Jen, und 陳尚仁. „A Cavity-Fed Slot-Coupled Feed Network for Patch Antenna Arrays“. Thesis, 2004. http://ndltd.ncl.edu.tw/handle/73972366878513808733.
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碩士國立暨南國際大學
通訊工程研究所
92
Conventional corporate design has been extensively used for the feed network of microstrip patch arrays. Uniform amplitude and phase to each element are required to achieve the goal of maximum gain. However, for large arrays, this design suffers the problem of low efficiency caused by the ohmic loss, the dielectric loss, and the parasitic radiation in the feed network. A novel feed work using cavity-fed and slot-coupled techniques for microstrip patch arrays is proposed in this thesis. Each array element is fed by a cavity in resonant mode through slot coupling. The entire design does not require any coplanar feeding structures to the array elements, therefore, excludes the possibility of causing the aforementioned losses. A single patch antenna with the proposed feeding structure is designed. Finite element method (FEM) is selected to calculate the required dimensions for optimum coupling. The results can be extended to the feed network for patch antenna arrays.
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Tsai, Jen-Kuei, und 蔡仁貴. „Dual-Band Slot Antenna Arrays Based on Composite Right-/Left-Handed Transmission Lines“. Thesis, 2017. http://ndltd.ncl.edu.tw/handle/s875kw.
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碩士國立臺灣大學
電信工程學研究所
105
In this thesis, four dual-band broadside antenna arrays incorporated with composite right-/left-handed (CRL H) microstrip lines are proposed. Two of them are designed for linear polarization, while the others are for circular polarization. All of the antenna arrays are based on slot antenna and with adequate gain. First, for linear polarization, linear arrays arranged along H-plane and E-plane directions are designed, respectively. Both arrays are composed of four slot antenna elements. In order to achieve broadside radiation, elements should be fed with in-phase excitation. This in-phase requirement should be satisfied at both operating bands. By combining CRLH transmission lines (TLs) with ordinary TLs to realize the array feeding network, the in-phase requirement can be achieved simultaneously at both desired bands. Besides, the CRLH TL can also be used to realize an equal power divider with 180 phase difference at both bands. This power divider is later on applied in the E-plane array. Second, for circular polarization (CP), two array designs are proposed with respectively the same and opposite handedness of CP at the two desired bands. The CRLH TLs are used to design the feeding network that provides 90 or 270 phase difference between adjacent perpendicular elements according to the handedness of CP. All the simulated and measured results are in good agreement.
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Alibakhshikenari, M., B. S. Virdee, C. H. See, Raed A. Abd-Alhameed, F. Falcone und E. Limiti. „Silicon-based 0.450-0.475 THz series-fed double dielectric resonator on-chip antenna array based on metamaterial properties for integrated-circuits“. 2019. http://hdl.handle.net/10454/18132.
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YesThe antenna array designed to operate over 0.450-0.475 Terahertz comprises two dielectric resonators (DRs) that are stacked vertically on top of each other and placed on the surface of the slot antenna fabricated on a silicon substrate using standard CMOS technology. The slot created in the silicon substrate is meandering and is surrounded by metallic via-wall to prevent energy dissipation. The antenna has a maximum gain of 4.5dBi and radiation efficiency of 45.7% at 0.4625 THz. The combination of slot and vias transform the antenna to a metamaterial structure that provides a relatively small antenna footprint. The proposed series-fed double DRs on-chip antenna array is useful for applications in THz integrated circuits.
Partially supported by innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424 and the financial support from the UK Engineering and Physical Sciences Research Council (EPSRC) under grant EP/E0/22936/1.
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Bartlett, Chad. „Design of an 8x8 cross-configuration Butler matrix with interchangeable 1D and 2D arrays“. Thesis, 2019. http://hdl.handle.net/1828/10989.
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An ever-increasing demand for wider bandwidths in communication, radar, and imaging systems has emerged. In order to facilitate this growing demand, progressive research into millimeter-wave technologies has become vital in achieving next generation networks such as 5G. Being cost effective and easy to manufacture, Substrate Integrated Waveguide (SIW) circuits have been demonstrated as a viable candidate for high-frequency applications due to their low-loss, high quality-factor, and high power-handling capabilities.Research on beam-forming networks, specifically the Butler matrix, has demonstrated powerful beam-steering capabilities through the use of passive component networks. Through these clever configurations, a cost effective and robust option is available for us to use. In order to further millimeter-wave research in this area, this thesis presents a modified configuration of the Butler Matrix in SIW that is physically reconfigurable; by separating the Butler matrix from the antenna array at a pre-selected point, the array can be easily interchanged with other 1-Dimensional,and 2-Dimensional slot antenna arrays. Although this system does not fall under the rigorous definitions of Reconfigurable Antennas, it should be noted that the interchangeability of 1 and 2 dimensional arrays is not typically expressed in Butler matrix configurations. Design and simulations are carried out in CST Microwave Studio to inspect individual components as well as system characteristics. Circuit prototypes are then manufactured and tested in an anechoic chamber to validate simulation results and the design approach.Graduate
2020-07-17
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Alibakhshikenari, M., B. S. Virdee, C. H. See, Raed A. Abd-Alhameed, F. Falcone und E. Limiti. „Surface wave reduction in antenna arrays using metasurface inclusion for MIMO and SAR systems“. 2019. http://hdl.handle.net/10454/18126.
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YesAn effective method is presented for suppressing mutual coupling between adjacent radiating elements which is based on metasurface isolation for MIMO and synthetic aperture radar (SAR) systems. This is achieved by choking surface current waves induced over the patch antenna by inserting a cross-shaped metasurface structure between the radiating elements. Each arm of the cross-shaped structure constituting the metasurface is etched with meander-line slot (MLS). Effectiveness of the metasurface is demonstrated for a2×2antenna array that operates over six frequency sub-bands in X, Ku and K-bands. With the proposed technique, the maximum improvement achieved in attenuating mutual coupling between neighbouring antennas is: 8.5 dB (8-8.4 GHz), 28 dB (9.6-10.8 GHz), 27 dB (11.7-12.6 GHz), 7.5 dB (13.4-14.2 GHz), 13 dB (16.5-16.8 GHz) and 22.5 dB (18.5-20.3 GHz). Furthermore, with the proposed technique (i) minimum center-to-center separation between the radiating elements can be reduced to 0.26λ0, where λ0 is 8.0 GHz; (ii) use of ground-plane or defected ground structures are unnecessary; (iii) use of short-circuited via-holes are avoided; (iv) it eliminates the issue with poor front-to-back ratio; and (v) it can be applied to existing arrays retrospectively.
H2020-MSCA-ITN-2016 SECRET-722424 and the financial support from the UK Engineering and Physical Sciences Research Council (EPSRC) under grant EP/E0/22936/1
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Nalumakkal, Priya Suresh. „Ultrawideband and wide-angle scan antenna element and small active phased arrays“. Thesis, 2023. https://etd.iisc.ac.in/handle/2005/6157.
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Wideband, wide-scan active phased arrays (APA) are widely used for multi-function radars, communication and electronic warfare. Although considerable research is available on the design and analysis of such antenna elements and arrays with large aperture, multi-octave wide scan phased antenna arrays with an electronically small aperture finds major application in electronic warfare (EW), is not well-developed. Based on a detailed literature survey on ultrawideband antenna for the wideband APA this research began with investigating different designs of tapered slot antenna (TSA) elements.
A study of the performance parameters like bandwidth, beamwidth, cross-polarization and beam-squint have been conducted for candidate antenna elements such as microstrip fed TSA, balanced antipodal TSA and stripline fed TSA (STSA). Based on these studies, STSA was selected as the most suitable candidate for meeting the requirement for antenna element. An STSA element with a wide beamwidth of 120° in H-plane with reflection coefficient less than -10 dB is designed.
Two different antenna arrays are proposed in this research to demonstrate the advantages of STAS as small aperture active array element for wideband phased arrays. Challenges in the design, analysis and characterization of moderately sized phased arrays using STSA element have been analyzed. Although seof interest in literature, of these a linear active phased array antenna that operates across 6 to 18 GHz frequency range, an array with wide-scan coverage of ±60° in H-plane is not developed.
The element pattern in phased arrays causes a squint in the main beam away from broadside. For small phased arrays this can be reduced by on-line calibration by taking a sample of signal at each element of the array. Therefore STSA is integrated with a -20 dB asymmetrical coupler at the feed for calibration and performance monitoring. In addition, the proposed STSA with integrated coupler is designed to have a wideband transition which allows a direct 50 Ω stripline feed. The isolated port of the coupler is internally terminated with a resistor using Ohmegaply resistive layer to improve reliability in airborne platform.
A linear array of 16 elements is designed and experimentally demonstrated. The main figure of merit of the array is realised gain of the array over the scan angle. A minimum element gain of 0 dB in array environment is obtained over the scan angle of ±60°, without any grating lobes at high frequency. It also demonstrated a cross-polarization of better than -25 dB at boresight and beam squint less than 1°. A staggered feeding arrangement is incorporated to accommodate the physical dimensions of connectors for minimum inter element spacing.
Conventionally the centre element pattern in array environment is used for obtaining the scanning characteristics of a large phased array. But, for small phased array, since the edge effects may be significant an average scan element pattern is proposed for array characterization. This gives an accurate result for the scan characteristics of array and can be used to correct array synthesis before full scale fabrication. This approach is validated by measuring the array pattern of the fabricated array with transmit/receive module.
Second, an 8 element E-plane array operating over 1 to 6 GHz frequency range is proposed with scanning of 45° from broadside. This antenna covers D, E, F and G bands of EW system. A novel STSA has been investigated across this bandwidth. Here the radiating part of tapered slot antenna is ended with an elliptical stub instead of circular stub which gives the same performance that of circular stub with reduced overlap with the radial stripline stub.
A compact broadband Wilkinson power divider feed network is designed along with array to characterise this. These edge effects are more severe in this array, especially at the low frequency of the operation band and methods to overcome this are investigated. Approaches of additional dummy edge elements or modifying edge elements have been investigated by simulations to reduce edge effects. An approach of adding 3D caps at the edges has been found to be more effective in this regard.
To summarize, methods for designing high performance multi-octave stripline fed tapered slot antenna elements and their arrays in the E- and H-plane have been developed using simulations and validated by experiments. These antennas are particularly suited as small aperture arrays in EW applications.
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Yin, Ching-Yu, und 殷崇禹. „The Study of Dual-Band Slot Antenna and Slot Antenna Array“. Thesis, 2000. http://ndltd.ncl.edu.tw/handle/49891097272044972574.
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碩士國立交通大學
電信工程系
88
In this report, we present the study of a dual-band (2.45GHz and 5.78GHz) slot antenna. And also development of a design 2.45GHz slot antenna arrays. In the first part, we present a novel dual-band microstrip-fed slot antenna for wireless communication systems at 2.45GHz and 5.78GHz. The first higher order modes of a slot antenna is utilized to create the dual-band antenna characteristic. The slot antenna is originally designed to radiation at 2.45GHz. By adding a stub at the ground plane, we can create another resonant frequency at 5.78GHz. We also integrate it with a band separator, so we can precisely measure the transmitting and receiving signals. We can conclude the dual-band microstrip-fed slot antenna is suitable for transceiver system by measured results. In the second part, 2.45GHz parallel feeding slot antenna array is investigated. Compare the bandwidth and power combining ability of series feeding slot microstrip-fed slot antenna, the parallel feeding microstrip-fed slot antenna, the later has wider bandwidth and larger power combining ability. Therefore, a set of 2 -element slot antenna array and set of 4-element slot antenna array are studied in this design. Good agreement has achieved between the theoretical and measured results.
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Huang, Tzung-Fang, und 黃宗訪. „CPW-fed slot and microstrip antenna analysis and slot antenna array design“. Thesis, 1999. http://ndltd.ncl.edu.tw/handle/15328082494886303293.
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博士國立臺灣大學
電機工程學研究所
87
Slot and slot-coupled patch antennas fed by the coplanar waveguide are investigated by using the full-wave analysis based on the Galerkin''s moment method in the spectral domain approach in this dissertation. The coupling slot is etched on the conducting plane of the coplanar waveguide and placed in the direction perpendicular to the transmission line. The equivalent magnetic currents in the coupling slot and in the slots of the coplanar waveguide are all expanded by the subsectional rooftop basis functions, while the equivalent surface electric current density on the microstrip antenna is represented by the entire domain basis functions if necessary. These equivalent currents are solved by the full-wave analysis using the Galerkin weighting procedure, and the reflection coefficient is extracted from the magnetic current distribution on the coplanar waveguide utilizing the matrix pencil technique. All the theoretical results are verified by the measurements and the comparisons show a good agreement between them. Investigation begins with a wide slot antenna fed by a coplanar waveguide. To model the wide slot accurately, the transverse magnetic current component is introduced and more than one longitudinal components are used across the slot. With this study, we can realize how to model the equivalent magnetic current to get a good agreement between theory and experiment. The variations of the characteristics of the inductive or capacitive slot antennas with parameters such as the slot width, slot length, and center strip width of the coplanar waveguide are presented and their corresponding variations in the bandwidth and the resonant frequency are also discussed. The spectral domain Green''s functions and the method of Stationary Phase are also used to calculate the front-to-back radiated power ratio for the CPW-fed slot antenna on a single dielectric substrate. A very simple formulation for the front-to-back radiated power ratio is obtained by assuming that the substrate and metalization is infinite in extend. With this formula, the substrate thickness and dielectric constant can be chosen and designed properly for CPW-fed slots. The same research for the inductive and capacitive patch antenna fed by the coplanar waveguide are also studied in this dissertation. There are more variable parameters such as the slot width, slot length, patch width, and patch length for us to design the patch antenna. The variations of the bandwidth and the resonant frequency with different parameters are also compared to each other. Finally, a simplified procedure for designing the slot antenna array excited by a coplanar waveguide is proposed. Moment method analysis and matrix pencil approach are adopted to calculate the scattering parameters and hence the self-admittance of each slot. The mutual admittances between the slots are calculated from the formulas derived for the complementary strip dipoles based on the reciprocity theorem and via Booker''s relation. Then the transmission line theory is used to calculate the input impedance of the array, and an iterative process is employed to obtain a matched design for a desired slot voltage distribution. A four-element slot array is fabricated and measured using this design procedure. Calculated results are in good agreement with measurements.
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Wu, Kuo-Hsi, und 吳國璽. „Design of CPW-Fed Slot Array Antenna“. Thesis, 1999. http://ndltd.ncl.edu.tw/handle/96093995052093374540.
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碩士國立臺灣大學
電信工程學研究所
87
The demand for wireless communication is experiencing unprece- dented growth. Smart antennas generally consist of an antenna array combined with signal processing and are used mainly for high-performance wireless system. So the design of the antenna array is more and more important. The purpose of this study is to design a cpw-fed slot antenna array with a large number of elements. A carefully synthesized large array can suppress the side lobes of its radiating pattern. In our design, we analyze the self- and mutual- admittances of the slots in the array first. Then the transmission line theory is used to calculate the input impedance of the array, and an iterative process is employed to obtain a matched design and the required sizes of the slots for a desired slot voltage distribution. Arrays with various number of elements are designed using this procedure at 7GHz, 14GHz and 22GHz. In all the cases, test pieces are carefully fabricated and measured to verify our design.
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Tsai, Yi-Ting, und 蔡伊婷. „Circularly polarized tapered slot antenna array design“. Thesis, 2016. http://ndltd.ncl.edu.tw/handle/35759996389483571277.
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碩士國立彰化師範大學
電子工程學系
104
In this paper, the design of the antenna, is divided into three main structures: half-wave dipole antenna (with BALUN), branch-line coupler, and fermi arrays antenna. The first structure is a half-wave dipole antenna (with BALUN), as the lumped port, and adjusting the size of the triangle under the antenna impedance matching results. The second structure is a branch-line coupler, the phase difference of 90 degrees features, so the antenna has a positive and negative polarity of the two properties. The third structure is a fermi arrays antenna, with its tapered slot features to the energy conducting out.
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紀權洲. „Design of the wideband slot array antenna“. Thesis, 2007. http://ndltd.ncl.edu.tw/handle/48731075881746965960.
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碩士明新科技大學
電子工程研究所
95
Abstract In this thesis, the printed rectangle slot antenna is designed by T-shaped microstrip-fed method. Otherwise, we discuss and analysis about the broadband characteristics. The printed rectangle slot antennas are all using microstrip-line-fed method that can let the printed rectangle slot antenna has the characteristic of simple structure. Additionally, in order to increase the bandwidth and gain of antenna, we design the Two-element and Four-element T-shaped microstrip-fed printed rectangle slot antennas dividedly; we test and verify the characteristics of high frequency and broad band for designed antennas by real practices. In this thesis, we research the single T-shaped microstrip-fed printed rectangle slot antenna firstly. It is like to design a rectangle slot in the ground. Furthermore, we design a T-shaped microstrip-fed in patch and then combine each other by couple method. It can enable the proposed antenna have the bandwidth characteristic. The bandwidth of impedance can up to 51 percentages. In the next, we design the Two-element and Four-element T-shaped microstrip-fed printed rectangle slot antennas dividedly to achieve the goal of increasing bandwidth based on previous antenna structure. In the Two-element T-shaped microstrip-fed printed rectangle slot antenna, we try to design two sections for comparing different operation frequency at low frequency (790MHz~1.66GHz) and medium frequency(1.667GHz~ 2.957GHz). The bandwidth of impedance is 64%(1.68~ 2.96GHz) on the part of Two-element T-shaped microstrip-fed printed rectangle slot antenna, but the Four-element is 55.5%(1.63~ 2.74GHz) that we can find the Four-element bandwidth of impedance is not increasing. However, the maximum gain of Two-element is 5.58dBi and the Four-element is up to 6.90dBi. At last, in order to improve the problem of the bandwidth of impedance for Four-element T-shaped microstrip-fed printed rectangle slot antenna, the Eight-element slot antenna was proposed. After design and real practice, the Eight-element slot antenna’s bandwidth of impedance is exalt to 90.8%(1.51~ 3.97GHz) and the gain is exalt to 9.43dBi. For the previous results, we can find the proposed method of T-shaped microstrip-fed printed rectangle slot antenna is really have the characteristics of high-gain and bandwidth. Keywords: microstrip array antenna, wide-band, high-gain.
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HUANG, ZONG-FANG, und 黃宗訪. „Coplanar waveguide fed slot array antennas“. Thesis, 1993. http://ndltd.ncl.edu.tw/handle/40128273237001752275.
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Cooley, Michael Edward. „Analysis of infinite arrays of endfire slot antennas“. 1992. https://scholarworks.umass.edu/dissertations/AAI9219420.
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Tapered slot antenna arrays have been increasingly studied and utilized in recent years. These arrays are well suited for many aerospace applications due to their potentially ultra-wide (3:1 or more) bandwidths (1). These arrays are also candidates for focal plane imaging systems (2), (3), (4), (5) and spatial power combining (6), (7). In recent years, numerous phased arrays and imaging arrays of tapered slot antennas have been designed and developed (8), (9), (10), (11). These array designs were based primarily on empirical approaches including, in some cases, the use of infinite array waveguide simulators. Analytical approaches to the design of such arrays are now being pursued to provide more rigorous design tools for future tapered slot array designs. This dissertation focuses on the analysis of infinite arrays of endfire slot antennas, with emphasis on tapered slot antenna arrays. Two full-wave moment methods of analysis have been developed and each has been validated by comparison with waveguide simulator measurements. Both methods are characterized by an initial application of the equivalence theorem at a plane in front of the array which offers computational advantages and modeling flexibilities. The first analysis, referred to as the air-dielectric analysis, has been used to perform parameter studies of tapered slot array radiation and scattering for some typical array geometries. Array input impedances versus frequency and scan angle were computed for five prototypical element geometries. For several of the arrays, the impedance varied rather moderately over the approximately 2:1 frequency band, but these impedances were also significantly inductive. This inductance could be due, at least in part, to the feed model which is used to drive the array elements. Principle plane active element patterns for these prototypical arrays were also computed.