Tesis sobre el tema "Compacts arrays"
Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros
Consulte los 50 mejores tesis para su investigación sobre el tema "Compacts arrays".
Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.
También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.
Explore tesis sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.
Touhami, Abdellah. "Optimisation multi-objectif d'antennes superdirectives compactes à balayage de faisceau pour des passerelles domestiques 5G sans fil". Electronic Thesis or Diss., Université de Rennes (2023-....), 2024. http://www.theses.fr/2024URENS002.
Texto completoThe evolution of wireless communication impose the need for more sophisticated antenna architectures, combined with antenna diversity and beamforming techniques. This type of antenna offers new possibilities for wireless applications in terms of spectral efficiency, radio link reliability, reduced environmental impact and increased communications system capacity. However, conventional beamforming techniques often lead to a significant increase in antenna size. As a result, the integration of such systems into small wireless devices is relatively limited. Compact, superdirective antenna arrays offer an innovative and attractive solution for both beamforming needs and integration in small volumes. However, they exhibits multiple drawbacks, including low radiation efficiency, low gain and narrow bandwidth. These drawbacks limit the usefulness of superdirective arrays to meet the needs of new-generation wireless technologies. In this thesis, we propose new multi-objectives optimization methods, based on network characteristic mode theory (NCM), array factor theory as well as artificial neural networks (ANN), for the design and the development of new compact, superdirective, efficient and wideband antenna architectures for 5G applications
Yong, Su-Khiong. "Compact antenna arrays for mobile communications". Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/11648.
Texto completoAbdelaziz, Abdelaziz Abdelmonem. "Compact multi-band microstrip planar antennas and arrays". Thesis, Cranfield University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315345.
Texto completoEck, James Arthur. "Compact Antennas and Arrays for Unmanned Air Systems". BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4297.
Texto completoCalvelo, Santos Daniel Emilio. "Observations of X-ray binaries using the Australia Telescope Compact Array-Compact Array Broadband Backend". Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/343755/.
Texto completoDahlberg, Timoteus. "Compact Representation and Efficient Manipulation of Sparse Multidimensional Arrays". Thesis, Umeå universitet, Institutionen för datavetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-92841.
Texto completoBougan, Timothy B. "COMPACT HIGH-SPEED DISK RECORDER". International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/608597.
Texto completoIn order to meet the high-speed and high-density recording requirements for today's development and testing environments, we are seeking to merge the cutting edge technologies of tiny, high-performance disk drives and field programmable gate arrays (FPGAs) to build a high-speed compact disk recorder (CHSDR). Specifically, we designed, built, and tested a multi-drive controller that handles the interleaving of data to eight inexpensive IDE drives. These drives and controller comprise a "cell" capable of transferring data at 2.45 MB/sec (4 to 5 times the rate of a single drive). Furthermore, these "cells" can be run in parallel (with a single controller interleaving data between the cells). This "tree" effect multiplies the data rate by the number of cells employed. For example, 8 cells (of 8 drives each) can reach nearly 20 MB/second (sustained) and can be built for less than $30,000. The drives we used are the size of match boxes (the Hewlett Packard KittyHawk). These tiny drives hold 42 megabytes each and can withstand 150 Gs while operating. The cell controller is a Xilinx 4005 FPGA. Furthermore, we've designed a 120 MB/sec RAM FIFO to buffer data entering the system (to account for unavoidable drive seek latencies). In short, the compact high-speed disk array is a small, relatively low cost recording solution for anyone requiring high data speed but modest data volume. Missile shots, nuclear tests, and other short-term experiments are good examples of such requirements.
Lovell, Jack James. "Development of smart, compact fusion diagnostics using field-programmable gate arrays". Thesis, Durham University, 2017. http://etheses.dur.ac.uk/12401/.
Texto completoVolmer, Christian. "Compact antenna arrays in mobile communications a quantitative analysis of radiator coupling". Ilmenau Univ.-Verl, 2009. http://d-nb.info/1000814149/04.
Texto completoVolmer, Christian. "Compact antenna arrays in mobile communications A quantitative analysis of radiator coupling". Ilmenau Universitätsbibliothek Ilmenau, 2010. http://d-nb.info/1001147197/34.
Texto completoIp, Kenneth Ho Yan. "A compact four-element injection-locked scanning antenna array". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63018.pdf.
Texto completoRai, Binay. "X-ray view of compact objects". Thesis, University of North Bengal, 2021. http://ir.nbu.ac.in/handle/123456789/4755.
Texto completoTu, Wen-Hua. "Wideband phased array antennas and compact, harmonic-suppressed microstrip filters". [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1110.
Texto completoKim, Sunghwan. "Phase shifter approaches for compact low-power phased array transmitters". Diss., [La Jolla] : University of California, San Diego, 2010. http://wwwlib.umi.com/cr/ucsd/fullcit?p3398530.
Texto completoTitle from first page of PDF file (viewed May 5, 2010). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 103-109).
Zhu, Fuguo. "Compact antennas and array for ultra-wideband communications and radars". Thesis, University of Kent, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.654097.
Texto completoSpencer, Jonathan Cullinan. "A Compact Phased Array Radar for UAS Sense and Avoid". BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5837.
Texto completoDeJean, Gerald Reuben. "Design of compact antennas in multilayer technology for wireless communications : WLAN applications". Available online, Georgia Institute of Technology, 2005, 2004. http://etd.gatech.edu/theses/available/etd-12092004-162859/unrestricted/dejean%5Fgerald%5Fr%5F200505%5Fmast.pdf.
Texto completoJoy Laskar, Committee Member ; Manos Tentzeris, Committee Member ; John Papapolymerou, Committee Chair. Includes bibliographical references.
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.
Texto completoQC 20130121
EU Erasmus Mundus External Cooperation Window TANDEM
Lepkowski, Stefan. "An ultra-compact and low loss passive beamforming network integrated on chip with off chip linear array". Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53599.
Texto completoDebard, Alexandre. "Analyse et optimisation d'antennes réseaux compactes superdirectives". Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALT058.
Texto completoThe purpose of this thesis is to study and seek improvement of the superdirective antenna array technology. This technology has been recently re-examined in the literature since it can bring some interesting functionalities in the future telecommunication applications. The examination of this type of antenna is thus conducted through the use of Spherical Wave Expansion which allows for the general study of directivity limits as well as gain limits, considering lossy antennas. The classical theory of end-fire array antennas is also reviewed, in the case of uniformly spaced tapered arrays, providing theoretical evaluation of efficiency and sensitivity to source feeding precision.Infinitesimal dipoles and Huygens sources are considered in a proposed development that links array theory and Spherical Wave Expansion. This contribution provides a formal proof for the directivity limit of Huygens-source-based end-fire arrays as well as an upper bound for the directivity of dipole-based arrays, when the inter-element spacing tends to zero. Moreover, it is shown how classical array theory can also be used to derive excitation coefficients that maximize gain rather than directivity, when loss resistances are considered. An examination over antenna size is also made to demonstrate which conditions are most favorable for the use of such supergain or superdirective end-fire array optimization.In a second part, practical implementations of superdirective antennas are surveyed, focusing on Huygens sources and compact end-fire array designs. The chosen implementation architecture of parasitic element arrays is then detailed and studied, in order to minimize the requirement for negative or positive resistive loads. This lead to the design and measurement of five prototypes that aim at achieving the maximum possible gain or directivity for a limited radiator size, with two-, three- and four-dipole end-fire arrays
Zepeda, Paola. "Modeling and design of compact microwave components and systems for wireless communications and power transmission". Texas A&M University, 2004. http://hdl.handle.net/1969.1/322.
Texto completoSteffens, Christian [Verfasser], Marius [Akademischer Betreuer] Pesavento y Marc [Akademischer Betreuer] Pfetsch. "Compact Formulations for Sparse Reconstruction in Fully and Partly Calibrated Sensor Arrays / Christian Steffens ; Marius Pesavento, Marc Pfetsch". Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2018. http://d-nb.info/1153123495/34.
Texto completoAnreddy, Vikram R. "Indoor MIMO Channels with Polarization Diversity: Measurements and Performance Analysis". Thesis, Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-04112006-093641/.
Texto completoIngram Mary Ann, Committee Chair ; Durgin, Gregory David, Committee Member ; Williams, Douglas B, Committee Member.
Hoffman, Jeffrey Dean. "Using Blind Source Separation and a Compact Microphone Array to Improve the Error Rate of Speech Recognition". PDXScholar, 2016. https://pdxscholar.library.pdx.edu/open_access_etds/3367.
Texto completoGholami, Mehrdad. "A C-Band Compact High Power Active Integrated Phased Array Transmitter Module Using GaN Technology". Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36045.
Texto completoLiu, Yuanzhi. "Compact Omnidirectional Millimeter-Wave Antenna Array Using Substrate Integrated Waveguide Technique and Efficient Modeling Approach". Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42031.
Texto completoVolmer, Christian [Verfasser], Matthias [Akademischer Betreuer] Hein, Reiner [Akademischer Betreuer] Thomä y Klaus [Akademischer Betreuer] Solbach. "Compact antenna arrays in mobile communications : a quantitative analysis of radiator coupling / Christian Volmer. Matthias Hein. Reiner Thomä. Klaus Solbach". Ilmenau : Universitätsbibliothek Ilmenau, 2010. http://d-nb.info/1001147197/34.
Texto completoNaqiv, Syed Aftab. "A Compact Cylindrical-shape Microstrip Structure with Cloaking Properties for Mutual Coupling Reduction in Array Antennas". Diss., North Dakota State University, 2014. http://hdl.handle.net/10365/24666.
Texto completoNaqvi, Syed Aftab. "A Compact Cylindrical-Shape Microstrip Structure with Cloaking Properties for Mutual Coupling Reduction in Array Antennas". Diss., North Dakota State University, 2014. https://hdl.handle.net/10365/27377.
Texto completoRosette, Keith Andrew. "Investigation of a compact acoustic source array for the active control of aircraft engine fan noise". Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-12302008-063020/.
Texto completoFarjam, Aslan. "Influence of Alumina Addition to Aluminum Fins for Compact Heat Exchangers Produced by Cold Spray Additive Manufacturing". Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33383.
Texto completoWestrick, Michael A. "Compact Wire Antenna Array for Dedicated Short-Range Communications: Vehicle to Vehicle and Vehicle to Infrastructure Communications". University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1345081406.
Texto completoRoberts, Adam Kaleo. "Improvements, Algorithms and a Simulation Model for a Compact Phased-Array Radar for UAS Sense and Avoid". BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6314.
Texto completoWang, Kun [Verfasser], Thomas [Akademischer Betreuer] Eibert y Wolfgang [Akademischer Betreuer] Menzel. "Investigations on Compact Antenna Arrays for Multiple Input Multiple Output Communication Systems / Kun Wang. Betreuer: Thomas Eibert. Gutachter: Thomas Eibert ; Wolfgang Menzel". München : Universitätsbibliothek der TU München, 2016. http://d-nb.info/1081768002/34.
Texto completoPralon, Mariana Verfasser], Reiner [Akademischer Betreuer] [Thomä, Matthias [Gutachter] Hein y José Richardo [Gutachter] Bergmann. "Compact antenna arrays for efficient direction of arrival estimation / Mariana Pralon ; Gutachter: Matthias A. Hein, José Richardo Bergmann ; Betreuer: Reiner S. Thomä". Ilmenau : TU Ilmenau, 2017. http://d-nb.info/1178142310/34.
Texto completoButt, Safwat Irteza [Verfasser], Matthias [Akademischer Betreuer] Hein, Reiner S. [Gutachter] Thomä y Achim [Gutachter] Dreher. "Compact adaptive planar antenna arrays for robust satellite navigation systems / Safwat Irteza Butt ; Gutachter: Reiner S. Thomä, Achim Dreher ; Betreuer: Matthias Hein". Ilmenau : TU Ilmenau, 2016. http://d-nb.info/1178166546/34.
Texto completoButt, Safwat Irteza [Verfasser], Matthias [Akademischer Betreuer] Hein, Reiner [Gutachter] Thomä y Achim [Gutachter] Dreher. "Compact adaptive planar antenna arrays for robust satellite navigation systems / Safwat Irteza Butt ; Gutachter: Reiner S. Thomä, Achim Dreher ; Betreuer: Matthias Hein". Ilmenau : TU Ilmenau, 2016. http://nbn-resolving.de/urn:nbn:de:gbv:ilm1-2016000659.
Texto completoPralon, Mariana [Verfasser], Reiner [Akademischer Betreuer] Thomä, Matthias [Gutachter] Hein y José Richardo [Gutachter] Bergmann. "Compact antenna arrays for efficient direction of arrival estimation / Mariana Pralon ; Gutachter: Matthias A. Hein, José Richardo Bergmann ; Betreuer: Reiner S. Thomä". Ilmenau : TU Ilmenau, 2017. http://d-nb.info/1178142310/34.
Texto completoAlmeida, Filho Valdez Arag?o de. "Arranjos Log-Peri?dicos Compactos em Microfita com Elementos Fractais de Koch". Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15315.
Texto completoCoordena??o de Aperfei?oamento de Pessoal de N?vel Superior
This work aims to present how the application of fractal geometry to the elements of a log-periodic array can become a good alternative when one wants to reduce the size of the array. Two types of log-periodic arrays were proposed: one with fed by microstrip line and other fed by electromagnetic coupling. To the elements of these arrays were applied fractal Koch contours, at two levels. In order to validate the results obtained some prototypes were built, which were measured on a vector network analyzer and simulated in a software, for comparison. The results presented reductions of 60% in the total area of the arrays, for both types. By analyzing the graphs of return loss, it was observed that the application of fractal contours made different resonant frequencies appear in the arrays. Furthermore, a good agreement was observed between simulated and measured results. The array with feeding by electromagnetic coupling presented, after application of fractal contours, radiation pattern with more smooth forms than the array with feeding by microstrip line
Este trabalho tem como objetivo apresentar como a aplica??o de contornos fractais aos elementos de um arranjo log-peri?dico se torna uma alternativa bastante interessante quando se deseja reduzir as dimens?es do arranjo. Foram propostos dois tipos de arranjos log-peri?dicos: um com alimenta??o por linha de microfita e outro com alimenta??o por acoplamento eletromagn?tico. Aos elementos desses arranjos foram aplicados contornos fractais de Koch, em dois n?veis. Com a finalidade de validar os resultados obtidos foram constru?dos prot?tipos, que foram caracterizados experimentalmente em um analisador de rede vetorial e simulados em software, para compara??o. Os resultados mostraram redu??es de 60% nas dimens?es dos arranjos, para ambos os tipos. Atrav?s da an?lise dos gr?ficos da perda de retorno, p?de-se observar que a aplica??o dos contornos fractais fez com que aparecessem diferentes frequ?ncias de resson?ncia nos arranjos. Al?m disso, observa-se uma boa concord?ncia entre os resultados medidos e simulados. O arranjo com alimenta??o por acoplamento eletromagn?tico apresentou, ap?s aplica??o dos contornos fractais, menores valores de diretividade do que o arranjo com alimenta??o por linha de microfita
Ibraheam, Maysam [Verfasser], Matthias [Akademischer Betreuer] Hein, Reiner [Gutachter] Thomä y Michael [Gutachter] Meurer. "Design and testing of compact dual-band dual-polarized robust satellite navigation antenna arrays / Maysam Ibraheam ; Gutachter: Reiner Thomä, Michael Meurer ; Betreuer: Matthias Hein". Ilmenau : TU Ilmenau, 2020. http://d-nb.info/1210861771/34.
Texto completoCormier, Yannick. "Performance, Manufacturability and Mechanical Properties of Near-Net Shaped Pyramidal Fin Arrays for Compact Heat Exchangers Produced Using Cold Spray as an Additive Manufacturing Technique". Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34981.
Texto completoHarding, Matthew T. "An experimental investigation of the performance of staggered PIN-FIN Array laminar flow heat exchangers". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Mar%5FHarding.pdf.
Texto completoClauzier, Sébastien. "Conception et réalisation d'antennes intégrables en mâture pour les plateformes navales : applications aux communications V/UHF et à un radar de navigation à balayage électronique en bande X". Thesis, Rennes 1, 2013. http://www.theses.fr/2013REN1S067.
Texto completoThe need to communicate and detect potential enemies increases with the extension of maritime conflicts. This need impacts directly the number of antennas on naval platforms. However, this increase of aerials leads to several damaging effects: like coupling or high radar signature. To limit this effect, some companies have developed integrated mast design. This structure limits the coupling effect between aerials by a subdivision of the mast and provides an omnidirectional coverage for all antennas inserted inside the mast. The objective of the thesis is to design two antenna systems for the compact integrated mast (CmastTM) developed by the Constructions Mécanique de Normandie (CMN): a communication antenna in the V/UHF band and an electronically scanning antenna for a maritime navigation radar in X-band. For the communication in the V/UHF band, a broadband conical antenna has been developed (225-400MHz). This antenna provides an optimized radiation pattern to insure the communications between the ship and the aircrafts. An experimental validation has been done with a prototype. In the second study, we have developed an electronically scanning antenna for a navigation radar. This antenna is based on a transmit-array technology including an illuminating feed and an antenna which generates the appropriate radiation pattern. A large part of the study has been done on the feed, which illuminates an array with specific dimensions (1530mmx100mm). Three different near-field focusing feeds have been developed and some of them have been validated experimentally. Then, two architectures of transmit-array antennas have been studied, using two different technologies: printed technology and a mixed technology with waveguide and horn
Öztezel, Aslihan. "Le réexamen d'une décision pénale consécutif à un arrêt de la Cour Européenne des Droits de l'Homme, en droit français et turc comparés". Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0094/document.
Texto completoUnavailable
Pujol, Hadrien. "Antennes microphoniques intelligentes : localisation de sources acoustiques par Deep Learning". Thesis, Paris, HESAM, 2020. http://www.theses.fr/2020HESAC025.
Texto completoFor my PhD thesis, I propose to explore the path of supervised learning, for the task of locating acoustic sources. To do so, I have developed a new deep neural network architecture. But, to optimize the millions of learning variables of this network, a large database of examples is needed. Thus, two complementary approaches are proposed to constitute these examples. The first is to carry out numerical simulations of microphonic recordings. The second one is to place a microphone antenna in the center of a sphere of loudspeakers which allows to spatialize the sounds in 3D, and to record directly on the microphone antenna the signals emitted by this experimental 3D sound wave simulator. The neural network could thus be tested under different conditions, and its performances could be compared to those of conventional algorithms for locating acoustic sources. The results show that this approach allows a generally more precise localization, but also much faster than conventional algorithms in the literature
Pozzobon, Nicola. "A Level 1 Tracking Trigger for the CMS Experiment at the LHC Phase 2 Luminosity Upgrade". Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3422049.
Texto completoDurante il secondo decennio di operazioni al Large Hadron Collider, a partire dall'anno 2020, è previsto un notevole aumento della luminosità istantanea del collisionatore, di un ordine di grandezza superiore rispetto a quella di progetto. Questa luminosità presenta numeose sfide per gli esperimenti a LHC. Il Tracciatore attualmente impiegato nell'esperimento Compact Muon Solenoid dovrà essere rimpiazzato con un sistema in grado di garantire una tracciatura di qualità eccellente ad alte luminosità e, allo stesso tempo, fornire informazioni utili per l'attuale "Livello 0" del sistema di Trigger a CMS, alla frequenza di collisioni di 40 MHz. Le richieste minime per un Trigger basato sul Tracciatore sono la capacità di confermare la presenza di tracce ad alto pT associate a Trigger di Livello 0 ottenuti con i Calorimetri o i rivelatori di muoni. La capacità di fornire criteri efficaci di isolazione può essere ulteriormente richiesa e in ogni caso migliorerebbe significativamente le prestazioni del Trigger. Il rateo dei dati associati con la generazione nel Tracciatore di informazione di Trigger può essere mantenuto in una larghezza di banda sufficientemente maneggevole richiedendo che i moduli sensitivi siano in grado di ridurre localmente i dati. I principali candidati per una simile riduzione locale del rateo i dati sono caratterizzati dalla capacità di fornire la direzione della traccia nel piano trasverso, oltre alla sua posizione, da cui poter dedurre la quantità di moto della traccia stessa. Questi "pT-modules" trasmetterebbero di conseguenza al Trigger di primo livello degli abbozzi di traccia ("stub") generati da particelle con pT al di sopra di 2 GeV/c. La scelta di una simile soglia permetterebbe la riduzione dei dati di un fattore superiore a 10, consentendo quindi un rateo facilmente tollerabile. I moduli di Trigger possono essere realizzati con due sensori di silicio paralleli leggermente separati, caratterizzati da una risoluzione sulla misura del singolo punto d'impatto tale che gli stub, ottenuti tramite correlazione tra i punti misurati nel modulo, possano fornire un'adeguata misura della direzione della traccia, nonostante il braccio di leva sia dell'ordine del millimetro. Un'ipotetica configurazione per il Tracciatore, composto da "lunghi barili", che prevede un Tracciatore esterno realizzato totalmente con moduli di Trigger, è stata proposta. Essa è particolarmente flessibile negli studi di simulazione per il Trigger realizzato con il Tracciatore giacché consente di combinare tra loro, tramite proiezioni geometriche, le informazioni provenienti da diversi strati del Tracciatore. Pertanto è un campo di prova per confrontare le prestazioni di diverse concezioni e diverse configurazioni. Il Tracciatore proposto permette anche la generazione di oggetti più articolati degli stub per il Trigger, come ad esempio le "tracklet", che consistono in coppie di stub opportunamente associate tra loro, le quali possono a loro volta essere usate come punto di partenza per la costruzione di Tracce di Primo Livello. La scelta di moduli di Trigger realizzati con sensori accoppiati è rafforzata da risultati recenti ottenuti con dei prototipi innovativi di rivelatori a Pixel Monolitici durante dei test sotto fascio riportati in questa tesi. Lo sviluppo di simulazioni per un Trigger con il Tracciatore è anch'esso presentato come un significativo progresso verso la progettazione di un nuovo Tracciatore realistico e capace di fornire informazioni utili per il Trigger. Particolarmente impegnativo è lo sforzo per un Trigger che selezioni i leptoni tau prodotti in numerosi processi rari di interesse per gli esperimenti a LHC. Le prestazioni di un Trigger con il Tracciatore su stati finali contenenti leptoni tau saranno fondamentali a luminosità molto elevate e sono illustrate alla fine di questo documento, come naturale prosecuzione del lavoro descritto.
Fang, Han-Sheng y 方瀚陞. "Decoupling of Compact Multiple Antenna Arrays Using Cancellation Technique". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/pv5k8f.
Texto completo國立臺北科技大學
電子工程系博士班
105
A cancellation technique that not only can achieve better isolation but has also wide usability for any multiple antennas, is proposed in this dissertation. The technique involves the model construction of multiple antennas including the calculation of the required be cancelled energy in the decoupling process and correcting the impedance matching of each port to accomplish the decoupling of multiple antenna arrays. In order to verify the effect of this cancellation technique, this dissertation presents a quad-antenna array with cancellation technique that is derived from a single antenna structure with a step-by-step illustrates process for proper design. Finally, MIMO performance of the multiple antennas is assessed through the evaluated and measured branch power ratio, envelope correlation coefficient, and the diversity gain. The results showed that when compared with the dual-antenna array, the dual-antenna array implemented with cancellation technique has the envelope correlation coefficient that is lowered by 0.43 and has an enhanced diversity gain higher by 3.5 dB. Next, comparing with the quad-antenna array show that implementing with cancellation technique has the envelope correlation coefficient that lowered by 0.4 and diversity gain higher by 6.5 dB. Therefore, the proposed cancellation technique can be used to achieve better MIMO performance in compact multiple antennas.
"Coupled resonator decoupling networks for compact antenna arrays of advanced communication systems". 2014. http://repository.lib.cuhk.edu.hk/en/item/cuhk-1290678.
Texto completoIn parallel to advances in MIMO technologies, there is an irreversible trend that more and more communication protocols together with their respective antennas and radio transceivers are integrated into one compact unit. The radio systems of different protocols may work in very closely adjacent frequency bands or even overlapped bands. The coexistence of these multiple antennas has also become a concern from both industry and academic communities.
However, since the number of antenna elements is increasing in more and more compact devices, the physical limitation on inter-element spacing cannot be easily transcended, which will lead to destructive mutual coupling interference as well as pattern/spatial dependent correlation. In a multi-antenna system, the signals at all antenna ports are coded differently either to increase the packet rate or simply because that they belong to different radio transceivers. If unwanted signals are coupled to the ports, the signal-to-noise ratio will be deteriorated. Furthermore, the far-field patterns of closely spaced antennas are highly correlated and the signal envelope correlation will become significantly large. All these negative impacts will greatly diminish the channel capacity and the data throughput. Such drawbacks restrain the use of multiple antenna systems. It is therefore vital to develop a simple, broadband and effective decoupling technique for compact multiple antenna systems/arrays in advanced communication systems.
The major objectives of this thesis are (1) to innovate a new antenna decoupling technique called shunt type of coupled resonator decoupling networks (S-CRDNs) for wireless mobile terminal antennas; (2) to develop the synthesis theory and the design methodologies of the shunt type of CRDNs (S-CRDN) for various of antenna arrays; (3) to extend the theory and the design concept to dual band S-CRDNs, three port S-CRDNs and a LTCC S-CRDN module for mobile terminal applications; (4) to develop a cascaded type of coupled resonator decoupling networks (C-CRDN) for base station and wireless routers antennas; (5) to innovate a novel decoupling technique for multiple element antenna arrays with dummy antennas arrays; and more importantly, (6) to explore innovative applications with experimentally verified superiority.
Based on the characteristics of the coupled antennas, the synthesis theory of S-CRDNs starts from a set of required admittance polynomials, the targeted coupling matrix can be obtained from the polynomials analytically for a second-order S-CRDN. Possible coupling topologies of S-CRDNs include, but not limited to, a second-order all pole S-CRDN, a second-order S-CRDN with source-load coupling, a high-order S-CRDN network for dual band applications and a three port S-CRDN for three-element antenna arrays. Moreover, the concept of a “one-fit-all” S-CRDN module base on LTCC technology is also proposed and investigated, which makes an integrated S-CRDN module antenna independent as long as the frequency range matches.
The general theory of C-CRDN is developed in this thesis based on the circuit model of a 4-port coupled resonators network, which is proposed to solve the antenna decoupling problem between two base station antennas, to which a high level of isolation between two adjacent frequency bands is required, for the first time. This type of CRDN is particularly useful when one antenna transmitting very high power energy in a vicinity to a receiver antenna that works in an adjacent frequency band with very high sensitivity.
A decoupling technique with appropriately designed dummy elements and their passive complex loading is also proposed in this thesis. The technique employs the characteristics of non-radiating antenna elements (dummy elements). Multiple dummy elements can be introduced to alter the mutual coupling characteristic the radiating antennas in the original compact array. Therefore, this technique is more suitable for decoupling problem of an array with multiple elements. It is demonstrated that for a four-element compact array, four dummy elements are sufficient to decouple the four radiating elements in a broadband sense. Additionally, each radiating element can be independently matched. This decoupling technique can be extended to antenna arrays with a high number of radiating elements.
Finally, necessary and important figures of merit for benchmarking a multiple element antenna array are introduced. Prototypes of multi-antenna systems with and without using proposed decoupling techniques are fabricated, measured and compared. A large number of experimental results have demonstrated the superiority and the significance of the proposed decoupling techniques for compact antenna arrays of advanced wireless communication systems.
下一代無線通訊系統與設備的飛速發展,極大的促進了多天線系統的開發與應用。多天線系統天生具有高數據吞吐率,并能夠確保傳輸的穩定性。根據香農定律,若想要提高一個系統的信道容量,要麼可以展寬系統帶寬,要麼可以適用多輸入多輸出(MIMO)系統。MIMO技術在發射端和接收端安置多個天線,以同時發送多路數據,大大提高了數據的吞吐率和信道容量。理想的狀態下,信道容量隨著收發天線的個數可以線性成倍增加。因此,新一代的小型化多天線系統正在成為未來發展的趨勢。
與此同時,現今無線通訊系統的發展趨勢越來越朝著小型化,集成化以及多功能化發展。這就意味著,越來越多的通信協議及其收發機和天線,將會集成到一個越來越小的終端設備上。另外由於頻譜資源的稀缺,這些共同工作的系統的頻帶越來越寬,頻帶之間的距離也越來越近。這些多天線的共存問題,也日益成為學術界和工業界關心的焦點問題。
但是,當終端的尺寸越來越小,而天線的個數越來越多的時候,天線之間的物理距離這個瓶頸是無法逾越的。如此受限的距離,不但造成了天線之間的相互干擾較大,也造成了他們方向圖和信道的強相關。在多天線系統中,各個天線處的信號編碼是不同的(包括提高數據速率和提高通信可靠性兩種不同的模式)。如果無用的信號耦合到了不該到的端口或者天線處,就會極大的影響信噪比和通信質量。另外,如果多天線的方向圖和信道是相關的話,信號的包絡相關性就會變得異常的大。這些都是嚴重影響多天線系統的性能的因素。因此,設計一種簡單的,寬帶的,有效的解耦技術,對於多天線系統是至關重要的。
本論文的主要目標是:(1)開發一種新的天線解耦技術,叫做並聯型耦合諧振腔解耦網絡,專門針對手機終端。(2)研究針對此解耦網絡的綜合設計手段,以針對不同的多天線陣列,都能有效的設計。(3)將此技術推廣到雙頻,多頻,多端口的多天線系統中。并研究利用低溫共燒陶瓷技術實現此類器件的小型化。(4)開發另一種級聯型耦合諧振腔解耦網絡,專門針對基站和路由器應用。(5)開發一種利用“假”天線進行解耦的新型技術。更重要的是(6)在實際使用場景中驗證所提出的各種解耦技術的有效性。
並聯型耦合諧振腔解耦網絡的綜合方法,需要受限根據耦合天線的特性和參數,得到一組電抗多項式,對於二階的網絡,所需要的耦合係數可以有這些多項式解析得到。實際上,並聯型耦合諧振腔解耦網絡的拓撲結構是多樣的,其中包括:兩階無交叉耦合型,兩階有交叉耦合及源負載耦合型,高階針對多頻的網絡以及三端口的網絡,專門針對三單元天線陣列。從並聯型耦合諧振腔解耦網絡,可以衍生出一種非常重要的基於低溫共燒陶瓷技術的“全能型”解耦網絡。這種網絡在頻率確定的情況下,可以適應各種不同的天線形式和耦合,非常適合在手機終端上廣泛採用。
本論文還討論了針對級聯型耦合諧振腔解耦網路的一般理論,以及其對應的電路模型和網絡參數。這種類型的網絡非常適合解決需要極高隔離度的基站天線解耦問題。這種網絡在本文中是業界首次提出的針對發射天線對領進頻帶接收機強幹擾的微波無緣網絡解決方案。
另外,一種採用“假”天線配合其電抗負載進行解耦的方法也將在文中提到。這種技術利用了並不輻射的“假”天線的寄生特性,通過引入若干不同空間排布的假天線陣,來解決原有天線陣的強互耦問題。這種方法的優越性是可以針對多種不同單元數和不同陣列排布的陣列。
最後,本文將會一一討論多種評估多天線系統性能指標的參數。包括隔離度,效率,包絡相關性,信道容量乃至吞吐率。作為比較,多種多天線系統,包括採用解耦網絡技術和不採用解耦網路技術的天線陣的各種性能參數,都在文中做了詳細比較。大量的實驗證明了採用解耦網絡的多天線系統的優越性。
Zhao, Luyu.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2014.
Includes bibliographical references.
Abstracts also in Chinese.
Title from PDF title page (viewed on 26, October, 2016).
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Su, Feng-Yi y 蘇峰毅. "Novel compact MIMO antenna arrays with port decoupling and high efficiency". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/q28ceq.
Texto completoHuang, Po-Chung y 黃柏彰. "Bio-inspired compact camera using curved microlens array". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/60969823444021845310.
Texto completo國立臺灣大學
光電工程學研究所
101
The human eye has simple structure, high resolution but curved retina. On the other hand, the compound eye has wider field of view but low resolution. In this thesis, we proposed a camera lens design combining with the principle of the insect compound eye and the human eye, simulating the compound eye structure by the microlens array and using two main lenses to simulate human’s lens. This system maintains the advantages and removes the shortcomings of the two structures. Comparing with the mobile phone camera lens with more than five lenses structure and limited field angle, this design contains 6.2 mm × 4.6 mm image plane size with small thickness (5 mm); large field of view (120°