Tesi sul tema "Multiband and wideband antenna"
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1
Mello, Rafael Gonçalves Licursi de. "Active and passive metasurfaces : methodology for the design of a low profile, beam-steerable, multiband, and wideband antenna". Electronic Thesis or Diss., Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAT025.
Abstract (sommario):
Les métasurfaces sont des matériaux artificiels qui peuvent être combinés avec des éléments micro-ondes traditionnels dans des solutions révolutionnaires. Les recherches sur l'utilisation des métasurfaces dans les rôles de réflecteur et/ou de superstrat d'antenne se sont considérablement intensifiées à partir du début des années 2020, en raison de leurs fonctionnalités innovantes alignées avec les dernières tendances en Télécommunications. Dans cette thèse, des méthodologies pour l'utilisation de métasurfaces passives et actives dans la conception d'antennes sont présentées. Une première méthodologie qui exploite à la fois les comportements proches du conducteur électrique parfait (CEP) et du conducteur magnétique parfait (CMP) d'un conducteur magnétique artificiel (CMA) bi-bande est utilisée pour concevoir une antenne directive multibande à faible encombrement. Cette méthodologie est validée avec un prototype pour les normes européennes 4G/5G et Wi-Fi 2.4/5/6E, fonctionnant dans les bandes suivantes : 2.40–2.70 GHz, 3.40–3.80 GHz, 5.17–5.83 GHz, and 5.93–6.45 GHz. De plus, une méthodologie pour gérer le mécanisme Fabry-Pérot dans une antenne composée d'une bow-tie avec les bords arrondis rainurés, d'un AMC passif bi-bande et d'une métasurface Huygens active multibande est présentée. Cette méthodologie est validée avec la conception d'une antenne multibande, directive, à faible encombrement qui effectue un dépointage du faisceau indépendant dans une des bandes de fréquences de fonctionnement. Grâce au contrôle des tensions de polarisation sur quatre colonnes de varactors dans la métasurface reconfigurable et multibande de Huygens, le faisceau peut être dynamiquement dépointé à ±51°, de manière continue, dans une gamme de fréquences comprise dans la gamme de fréquences 5G européenne (de 3.50 to 3.65 GHz). En même temps, les diagrammes de rayonnement concernant la 4G et le Wi-Fi 2.4/5/6E restent pratiquement inchangésMetasurfaces are artificial engineered materials that can be combined with traditional microwave components in ground-breaking solutions. The research on the use of metasurfaces in the roles of antenna reflector and/or superstrate considerably increased mainly from the beginning of the 2020s, because of their innovative functionalities in line with the ultimate Telecommunication trends. In this thesis, methodologies for the use of passive and active metasurfaces in the design of antennas are presented. A first methodology which exploits both the near-perfect electric conductor (PEC) and near-perfect magnetic conductor (PMC) behaviors of a dual-band artificial magnetic conductor (AMC) is used to design a low-profile, multiband, directive antenna. This methodology is validated with a prototype suitable for the European standards of 4G/5G and Wi-Fi 2.4/5/6E, operating within the following bands: 2.40–2.70 GHz, 3.40–3.80 GHz, 5.17–5.83 GHz, and 5.93–6.45 GHz. Additionally, a methodology to handle the Fabry-Pérot mechanism in an antenna composed of a grooved rounded-edge bow-tie, a passive dual-band AMC, and an active multiband Huygens metasurface is presented. This methodology is validated with the design of a multiband, directive, low-profile, antenna that performs an independent beam-steering in only one of the operating frequency bands. Through the controlling of the bias voltages over four columns of varactors in the reconfigurable, multiband Huygens metasurface, the beam may be dynamically steered in ±51°, in a continuous manner, in a frequency range lying inside the European 5G frequency range (from 3.50 to 3.65 GHz. All at once, the radiation patterns concerning the 4G and Wi-Fi 2.4/5/6E keep practically unaffected
2
Yousuf, Muhammad Amir. "Parametric Modeling of small terminals and Multiband or Ultra wideband Antennas". Palaiseau, Ecole polytechnique, 2011. https://pastel.hal.science/docs/00/63/48/66/PDF/Parametric_Modeling_of_UWB_antennas.pdf.
Abstract (sommario):
Depuis le lancement systèmes des communications d'ultra large bande (ULB) en courtes distances les facteurs comme la miniaturisation d'appareil et haut débit créer des grands défis pour les concepteurs d'antennes. Une façon de faire le travail de conception facile est du modéliser statistiquement la variabilité de comportement de rayonnement de l'antenne en fonction de sa géométrie. Tel effort est également utile pour la meilleure utilisation du canal de communication si on combine le modèle d'antenne avec ça. Cette thèse est une tentative vers la modélisation statistique des antennes ULB. Le sujet est confronté à deux défis majeurs, la création de la population statistiques considérable d'une classe(s) d'antenne et la modélisation du diagramme de rayonnement de l'antenne qui est composé de grand nombre de paramètres complexes. Dans cette thèse, nous essayons de répondre le premier en proposant une approche de conception générique pour les antennes planaires ULB et le second en présentant l'utilisation de technique l'ultra-compressé de modélisation paramétrique. L'approche de conception générique est basé sur des formes trapézoïdales et offre une grande flexibilité et polyvalence dans la conception des antennes ULB diverses. Cette approche montre une facilité importante dans l'optimisation d'antennes (également pour la création de la population), car elle réduit le nombre de paramètres qui contrôle la géométrie de l'antenne, sans compromettre le degré de liberté. Ultra-compressé modélisation paramétrique est basée sur deux méthodes de synthèse d'antenne, la méthode d'expansion singularité (SEM) et sphériques méthode d'expansion de mode (SMEM) qui permettent de réduire le nombre de paramètres complexes requis pour le diagramme de rayonnement de 99,9%, permettant à l'effort de modélisation possibles. Un modèle statistique de l'antenne biconique basé sur cette technique a été présentéSince the inception of short range Ultra Wideband (UWB) communication systems the factors like device miniaturization and high speed data rate create big challenges for antenna designers. One way to make the design job easy is to statistically model the variabilities of antenna radiation behavior as a function of its geometry. Such an effort is also useful for the better usage of the communication channel by combining the antenna model with it. This thesis is an attempt towards statistical modeling of UWB antennas. The subject faces two main challenges, the creation of sizeable statistical population of the class of antenna design(s) and modeling of antenna's radiation pattern which is composed of huge number of complex parameters. In this thesis we try to answer the former by proposing a generic design approach for UWB planar antennas and the latter by presenting the use of ultra-compressed parametric modeling technique. The generic design approach is based on trapezoidal shapes and offers great flexibility and versatility in designing various UWB antennas. This approach shows a significant ease in antenna optimization (also for population creation) as it reduces the no. Of parameters that controls the antenna geometry without compromising the degree of freedom. Ultra-compressed parametric modeling is based on two antenna synthesis methods, singularity expansion method (SEM) and Spherical mode expansion method (SMEM) that reduce the required no. Of complex parameters for the radiation pattern by 99. 9%, making the modeling effort possible. A statistical model of biconical antenna based on ultra-compressed modeling technique has been presented
3
Benomar, Ahmed. "Etude des Antennes à Résonateurs Diélectriques. : Application aux Réseaux de Télécommunications". Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0025/document.
Abstract (sommario):
Un développement technologique rapide dans le domaine de télécommunication, qu'il s'agisse de la téléphonie mobile, des réseaux sans fils, de la télévision par satellites, ou des applications radar (civiles ou militaires)...etc. est observé. Cet essor considérable a engendré d'énormes besoins et entraîne une évolution technologique majeure au niveau des antennes. Ces dernières doivent faire face aux différentes exigences, à savoir l'augmentation du gain, l'élargissement de la bande passante… et aux différents problèmes existant, à savoir le coût, l’encombrement…etc. Notre objectif est donc de concevoir des topologies d’antennes simples, à faible encombrement et à gain relativement élevé avec un fonctionnement multibande et/ou ultra large bande. Pour cela nous nous sommes orientés vers des antennes à résonateur diélectrique (ARD) dans les bandes UHF et SHF. Récemment, elles ont fait l’objet de plusieurs recherches et ont acquis un grand intérêt du monde académique et industriel. Les ARDs, par leurs simples et diverses géométries, peuvent être alimentées par différentes usuelles techniques. En outre, leurs tailles peuvent être plus petites que leurs homologues à savoir les antennes imprimées. Une première partie de ce travail s’est concentré sur l’étude des ARDs de forme cylindrique, puis une validation de l’outil de simulation par comparaison avec la mesure. En vue d’une utilisation multistandards, d’un élargissement des bandes de fonctionnement ou d’une modification de la fréquence, une seconde partie a été consacrée à l’étude de nouvelles topologies de résonateurs basées sur un empilement vertical et radial de deux cylindres, une topologie en multicouche et en anneau. Les résultats obtenus trouvent leurs applications dans le GSM900-DSC1800, UMTS, WIFI…A fast technological development in the telecommunications domain, as mobile telephony, wireless networks, TV over Satellite, Radar Applications (civil or military)…etc, is observed. This considerable growth has led to enormous needs and caused a major technological evolution in antennas. These have to face different needs such as gain improvement, bandwidth enlargement, and different existing problems, such as cost and overcrowding…etc. Though, our goal is to design antenna topologies that are simple, having Low overcrowding and relatively with high gain operating in multiband and/or ultra large. To achieve this we headed to Dielectric Resonator Antennas (DRA) in UHF and SHF bands. Recently they have been the subject of several studies and have gained great interest from both academic and industrial sectors. Due to their diverse and simple geometries, they can be fed with different usual techniques. Furthermore, they can be smaller than patch antennas. The first part of this work has focused on the study of cylindrical DRAs, and then a validation of the simulating tool has been done after comparison with measurement results. For a multi-standard utilization, enlargement antennas’ operating bands, to have bi-band behaviour, get a modification of the resonant frequency and also a reduction of the overcrowding, the second part is dedicated to the study of new resonator topologies based on a vertical and radial stack of two cylinders, and then a multilayer and ring topologies. The obtained results found their applications in GSM900-DCS1800-UMTS-WiFi…
4
Muscat, Adrian. "The design of planar low gain, wideband and multiband antennas employing optimisation techniques". Thesis, Queen Mary, University of London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271716.
5
Saleem, Rashid. "Towards an end-to-end multiband OFDM system analysis". Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/towards-an-endtoend-multiband-ofdm-system-analysis(e711f32f-1ac6-4b48-8f4e-58309c0482d3).html.
Abstract (sommario):
Ultra Wideband (UWB) communication has recently drawn considerable attention from academia and industry. This is mainly owing to the ultra high speeds and cognitive features it could offer. The employability of UWB in numerous areas including but not limited to Wireless Personal Area Networks, WPAN's, Body Area Networks, BAN's, radar and medical imaging etc. has opened several avenues of research and development. However, still there is a disagreement on the standardization of UWB. Two contesting radios for UWB are Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) and DS-UWB (Direct Sequence Ultra Wideband). As nearly all of the reported research on UWB hasbeen about a very narrow/specific area of the communication system, this thesis looks at the end-to-end performance of an MB-OFDM approach. The overall aim of this project has been to first focus on three different aspects i.e. interference, antenna and propagation aspects of an MB-OFDM system individually and then present a holistic or an end-to-end system analysis finally. In the first phase of the project the author investigated the performance of MB-OFDM system under the effect of his proposed generic or technology non-specific interference. Avoiding the conventional Gaussian approximation, the author has employed an advanced stochastic method. A total of two approaches have been presented in this phase of the project. The first approach is an indirect one which involves the Moment Generating Functions (MGF's) of the Signal-to-Interference-plus-Noise-Ratio (SINR) and the Probability Density Function (pdf) of the SINR to calculate the Average Probabilities of Error of an MB-OFDM system under the influence of proposed generic interference. This approach assumed a specific two-dimensional Poisson spatial/geometric placement of interferers around the victim MB-OFDM receiver. The second approach is a direct approach and extends the first approach by employing a wider class of generic interference. In the second phase of the work the author designed, simulated, prototyped and tested novel compact monopole planar antennas for UWB application. In this phase of the research, compact antennas for the UWB application are presented. These designs employ low-loss Rogers duroid substrates and are fed by Copla-nar Waveguides. The antennas have a proposed feed-line to the main radiating element transition region. This transition region is formed by a special step-generating function-set called the "Inverse Parabolic Step Sequence" or IPSS. These IPSS-based antennas are simulated, prototyped and then tested in the ane-choic chamber. An empirical approach, aimed to further miniaturize IPSS-based antennas, was also derived in this phase of the project. The empirical approach has been applied to derive the design of a further miniaturized antenna. More-over, an electrical miniaturization limit has been concluded for the IPSS-based antennas. The third phase of the project has investigated the effect of the indoor furnishing on the distribution of the elevation Angle-of-Arrival (AOA) of the rays at the receiver. Previously, constant distributions for the AOA of the rays in the elevation direction had been reported. This phase of the research has proposed that the AOA distribution is not fixed. It is established by the author that the indoor elevation AOA distributions depend on the discrete levels of furnishing. A joint time-angle-furnishing channel model is presented in this research phase. In addition, this phase of the thesis proposes two vectorial or any direction AOA distributions for the UWB indoor environments. Finally, the last phase of this thesis is presented. As stated earlier, the overall aim of the project has been to look at three individual aspects of an MB-OFDM system, initially, and then look at the holistic system, finally. Therefore, this final phase of the research presents an end-to-end MB-OFDM system analysis. The interference analysis of the first phase of the project is revisited to re-calculate the probability of bit error with realistic/measured path loss exponents which have been reported in the existing literature. In this method, Gaussian Quadrature Rule based approximations are computed for the average probability of bit error. Last but not the least, an end-to-end or comprehensive system equation/impulse response is presented. The proposed system equation covers more aspects of an indoor UWB system than reported in the existing literature.
6
Yurduseven, Okan. "Integration of microwave antennas with solar PV for multiband and wideband mobile, WLAN and WiMAX applications". Thesis, Northumbria University, 2014. http://nrl.northumbria.ac.uk/17466/.
Abstract (sommario):
The primary goal of this research is to investigate the existing photovoltaic antenna integration techniques and develop a new solar antenna integration topology in order to address the drawbacks of these techniques. With the increasing demands for low-profile antennas and a growing move towards the microgeneration of electricity, primarily by photovoltaics, photovoltaic antennas are of increasing importance with a growing amount of research in this area being developed. At present there are a number of designs for photovoltaic antennas which could be divided into two distinct categories. The first type is the use of solar cells as an RF ground plane, whilst the second type involves the use of solar cells as an RF radiating element. Both techniques bring significant challenges if they are to be widely adopted. Considering the first technique, using a solar cell as an RF ground plane introduces an optical shading problem, which significantly reduces the solar efficiency of the solar antennas using this integration topology. To this end, meshing the RF radiating element is investigated in this thesis to achieve optical transparency at the expense of increasing the cost and complexity of the fabrication process of photovoltaic antennas. Conversely, using a solar cell as an RF radiating element limits the ability to modify the resonance response using traditional RF bandwidth enhancement techniques due to the fact that solar cells need to have a homogeneous structure to achieve optimum solar performance. In order to address these challenges, a third solar antenna integration topology is proposed in this thesis. This method is based upon the use of solar cells as an RF stacked parasitic patch element suspended above the conventional RF radiating element of the integrated antennas. This integration topology enables the integrated solar cells to achieve an optimum solar efficiency due to their suspended position eliminating the shading problem. It also enables the RF radiating element to be modified to excite multiple TMmn propagation modes to achieve enhanced resonance response for multiband and wideband applications. This new topology has been further developed and applied to design a dual-polarised photovoltaic antenna for polarisation diverse communication systems, which has been extended to produce a photovoltaic array antenna for beam steering applications. This thesis addresses a major knowledge gap in the field of photovoltaic antennas. As a result of this, greater understanding of the design procedures of photovoltaic antennas and associated trade-offs from such designs is developed. Using this knowledge, novel designs that overcome the associated problems of current photovoltaic antennas are presented.
7
Garrido, Lopez David. "Low-Profile Multiband and Flush-Mountable Wideband Antennas for HF/VHF and K/Ka Band Applications". Thesis, University of Colorado at Boulder, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10245047.
Abstract (sommario):
This thesis introduces several novel antenna systems with extended performance capabilities achieved by either enabling multiple operation bands or by widening the bandwidth. Proposed theoretical concepts are successfully tested through simulations and experiments with excellent agreement are demonstrated. The designs developed in this thesis research are low-profile or flush mountable, enabling simple platform integration.
In the HF/VHF bands, the development of a novel low-profile multiband antenna for vehicular applications is presented. Specifically, an inverted-F antenna is used as a driven element, to operate at the lowest frequency of 27 MHz, whereas two parasitic elements are built as inverted-L monopoles to enable resonances at 49 and 53 MHz. To eliminate the need for an external matching network, an offset feeding technique is used. When the antenna is mounted on a vehicle and bent to follow its profile, a very low-profile is achieved (lambda/44) while good impedance and far-field performance are maintained across all three bands. The developed antenna system is not only electrically smallest among others found in the literature, but it is easily modified for other band selections and tuning of each band can be readily achieved.
Vehicular antennas are often used for high power applications, which may cause exposure of nearby individuals to possibly dangerous electromagnetic fields. To assess this hazard, the RF exposure of a vehicle's crew is discussed and an original and fast modeling approach for prediction thereof is demonstrated. The modeling approach is based on eigenmode analysis for acquiring a range of frequencies where the shielding effectiveness of a vehicle cabin is expected to be lower than average. This approach is typically much faster and requires less computational resources as compared to classical full-wave analyses. This analysis also shows that the position of an antenna system is critical and must be considered when high-power RF emissions are planned.
Following the same trend of antenna system size reduction with extension of capabilities in a congested spectral environment, the millimeter wave spectrum is explored next. Specifically, antenna systems for wideband amplitude only (AO) direction finding (DF) are thoroughly considered. Theory and design considerations are developed to fill gaps in open literature. Typical sources of errors are theoretically analyzed, and a discussion on limitations and advantages of different AO DF architectures is given.
Practical millimeter wave realizations of AO DF antenna front-ends in the K/Ka/Q bands (18-45 GHz) are developed using two different architectures: a passive phased-array and a squinted antenna system. For the former, a tightly coupled two-element tapered slot antenna (TSA) array with a stacked arrangement is developed. A novel enclosure of the array inside an absorbing cavity is proposed and improved system performance with flush mounted configuration is demonstrated. The squinted antenna system avoids the use of a beamformer, therefore reducing insertion loss and amplitude/phase imbalances to reduce DF errors. For design robustness, the same TSA element used in the phased-array configuration is used. A novel tapered cavity is also developed to stabilize H-plane radiation patterns and suppress sidelobes. It is seen that the squinted antenna AO DF front-end has better performance than the phased-array antenna system at the expense of larger size.
8
A, Rahim Mohamad Kamal. "Wideband active antenna". Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404129.
9
Adaniya, Hana L. "Wideband active antenna cancellation". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/47896.
Abstract (sommario):
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references (leaf 91).
There exists a simultaneous transmit and receive antenna system where the transmitted signal is creating wideband interference of the receiver. To resolve this interference problem, the isolation between the transmit antenna and the receive antenna must be increased. This thesis analyzes and discusses various strategies for antenna isolation and demonstrates the feasibility of an adaptive filtering approach on active signal cancellation. The final system design demonstrates that, with a broadband interference source in close proximity to a receiver, it is possible to provide 30 dB of isolation by using active cancellation.
by Hana L. Adaniya.
M.Eng.
10
Plaivech, Prachaya. "Wideband Antenna Over Ground Plane". Thesis, University of Sheffield, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515450.
11
Lourens, Jako. "A wideband monopole antenna design". Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80026.
Abstract (sommario):
Thesis (MScEng)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The successful operation of a man-pack VHF jamming system requires a compact and efficient antenna operating over a wide bandwidth. The design of such an antenna is the focus of this thesis. The antenna should be of a practical size for a portable system and it must radiate energy efficiently across a frequency bandwidth in excess of a decade. A practical „target‟ specification of such an antenna has been drawn up based on the performance of a commercially available system. Several possible antenna topologies, each with a variety of loading section options, are tested using “Full wave” electromagnetic modelling (FEKO). Each topology/loading-section is numerically optimised for load element values by considering both its gain and reflection coefficient. Results of the „optimally loaded‟ solution for each topology are then compared to each other to arrive at the best overall design. The best result is found to be the traditional monopole whip-type antenna, with four R-L loading sections spread along its length. The simulated results show that the proposed antenna can be expected to meet the target standing wave ratio (SWR) specifications while offering a gain advantage of between 5 and 10 dBi higher than is available commercially. The selected design is constructed and its performance measured.
AFRIKAANSE OPSOMMING: Die suksesvolle werking van ʼn mobiele VHF "jammer‟ benodig ʼn kompakte antenna met ʼn bruikbare benuttingsgraad wat oor ʼn wyeband funksioneer. Die ontwerp van so ʼn antenna is die fokus van hierdie tesis. Die antenna moet kompak genoeg wees om draagbaar te wees en moet ʼn bruikbare benuttingsgraad hê oor ʼn frekwensie-bandwydte van meer as 10:1. ʼn Praktiese spesifikasie is opgestel vir die antenna deur te kyk na die sigblaaie van beskikbare stelsels. “Volgolf” elektromagnetiese modelleringsagteware is daarna gebruik om ʼn parametriese ondersoek te loods van verskillende antennas. Verskillende topologieë is getoets met ʼn verskeidenheid van belaaide seksies waar die topologieë ge-optimaliseer was vir wins en weerkaatskoëffisiënt. Die resultate vir elke optimale oplossing is vergelyk.Opgrond van hierdie resultate is bevind dat die beste topologie die tradisionele monopoolmas "whip-type‟ antenna is met vier RL lading afdelings langs die lengte versprei. Analise word gebruik om te wys dat verwag kan word dat dit aan die aanwins en staande golf verhouding (SGV) spesifikasies sal voldoen met n 10 dB verhoging in aanwins vir n laer SGV. Die geselekteerde ontwerp is gebou en gemeet om te verifieer dat dit aan die spesifikasies voldoen.
12
Seko, Murilo Hiroaki. "Antenas planares de micro-ondas multibandas para terminais móveis de sistemas de comunicação sem fio". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-31072013-002544/.
Abstract (sommario):
Neste trabalho, foram desenvolvidas antenas planares de micro-ondas multibandas para aplicação em terminais móveis de sistemas de comunicação sem fio. Foi realizado um estudo sobre antenas planares de micro-ondas, com ênfase em técnicas de projeto que possibilitam a operação das mesmas em bandas largas e em múltiplas bandas. A partir dos conhecimentos adquiridos com esse estudo, foram propostas configurações de antenas para terminais móveis de sistemas atuais de telefonia móvel, de WLAN e de WPAN, sistemas esses que têm experimentado nos últimos anos uma grande popularização mundial. Por meio de um procedimento de projeto auxiliado por simulação eletromagnética computacional, as configurações propostas de antenas foram analisadas e otimizadas, visando atender às especificações de projeto estabelecidas para operação nos sistemas mencionados. O desempenho que pode ser obtido com essas configurações de antenas depende de diversos parâmetros geométricos das mesmas, resultando em flexibilidade de projeto para obtenção das bandas de operação desejadas. Protótipos das antenas projetadas foram construídos e caracterizados para validar as configurações propostas de antenas e o procedimento de projeto empregado. Foram desenvolvidas quatro antenas para operação em sistemas de telefonia móvel, de WLAN e de WPAN empregados no Brasil, na Europa e nos EUA: uma antena planar em F-invertido tri-band com configuração original para operação nas bandas dos padrões GSM, DCS e PCS; uma antena planar em F-invertido penta-band com configuração original para operação nas bandas dos padrões GSM, DCS, PCS e UMTS e na banda ISM de 2.400 MHz; duas antenas quad-band, uma delas planar em F-invertido e a outra monopolo impresso com configuração original, para operação nas bandas ISM de 2.400 MHz e de 5.800 MHz e nas bandas de 5.200 MHz e de 5.600 MHz. Os resultados experimentais dos protótipos construídos apresentaram, de modo geral, boa concordância com os resultados fornecidos por simulação e mostraram que as antenas desenvolvidas atenderam às especificações de projeto para elas estabelecidas. Por meio de ambos os resultados experimentais e de simulação, o desempenho das antenas desenvolvidas pôde ser verificado, e demonstrou-se a efetividade do procedimento de projeto adotado.In this work, multi-band microwave planar antennas for application in mobile terminals of wireless communication systems were developed. A study on microwave planar antennas was performed with emphasis on design techniques that enable their operation in wide bands and multiple bands. From the knowledge gained from this study, antenna configurations for mobile terminals of current mobile telephony, WLAN and WPAN systems, which have experienced in recent years great popularity worldwide, were proposed. By means of a design procedure aided by computer electromagnetic simulation, the proposed antenna configurations were analyzed and optimized in order to meet the design specifications established for operation in the afore mentioned systems. The performance that can be obtained with these antenna configurations depends on their several geometric parameters, resulting in design flexibility for obtaining the desired operation bands. Prototypes of the designed antennas were fabricated and characterized to validate the proposed antenna configurations and the design procedure employed. Four antennas were developed for operation in mobile telephony, WLAN and WPAN systems employed in Brazil, Europe and USA: a tri-band planar inverted-F antenna with novel configuration for operation in GSM, DCS and PCS standard bands; a penta-band planar inverted-F antenna with novel configuration for operation in GSM, DCS, PCS and UMTS standard bands and 2,400 MHz ISM band; two quad-band antennas, one of them planar inverted-F and the other printed monopole with novel configuration, for operation in 2,400 MHz and 5,800 MHz ISM bands and 5,200 MHz and 5,600 MHz bands. The experimental results from the fabricated prototypes exhibited, in general, good agreement with the results provided by simulation and showed that the developed antennas met the specifications established for them. By means of both simulation and experimental results, the performance of the developed antennas could be verified, and the effectiveness of the design procedure adopted was demonstrated.
13
Lai, Hau Wah. "Wideband meandering probe-fed patch antenna /". access full-text access abstract and table of contents, 2005. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?phd-ee-b19887383a.pdf.
Abstract (sommario):
Thesis (Ph. D.)--City University of Hong Kong, 2005."Submitted to Department of Electronic Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy." Includes bibliographical references (leaves 144-153).
14
Powell, Johnna 1980. "Antenna design for ultra wideband radio". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28542.
Abstract (sommario):
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, June 2004."May 2004."
Includes bibliographical references (p. 108-109).
The recent allocation of the 3.1-10.6 GHz spectrum by the Federal Communications Commission (FCC) for Ultra Wideband (UWB) radio applications has presented a myriad of exciting opportunities and challenges for design in the communications arena, including antenna design. Ultra Wideband Radio requires operating bandwidths up to greater than 100% of the center frequency. Successful transmission and reception of an Ultra Wideband pulse that occupies the entire 3.1-10.6 GHz spectrum require an antenna that has linear phase, low dispersion and VSWR [< or =] 2 throughout the entire band. Linear phase and low dispersion ensure low values of group delay, which is imperative for transmitting and receiving a pulse with minimal distortion. VSWR [< or =] 2 is required for proper impedance matching throughout the band, ensuring at least 90% total power radiation. Compatibility with an integrated circuit also requires an unobtrusive, electrically small design. The focus of this thesis is to develop an antenna for the UWB 3.1-10.6 GHz band that achieves a physically compact, planar profile, sufficient impedance bandwidth, high radiation pattern and near omnidirectional radiation pattern.
by Johnna Powell.
S.M.
15
Licul, Stanislav. "Ultra-Wideband Antenna Characterization and Modeling". Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/29487.
Abstract (sommario):
A new methodology is presented for characterizing an antenna system both in the time and frequency domain with one set of parameters using a singularity expansion method representation. A minimal set of parameter modeling antenna systems using the Matrix-Pencil method has been demonstrated. It has been shown that it is possible to obtain frequency-domain patterns from pole/residue models of antenna realized effective length. Thus, a pole/residue model of the antenna realized effective length presents a complete description in both the time and frequency domains. Once such a model is available, one can obtain the antenna pattern, directivity and gain in the frequency domain and the radiated transient waveform for an arbitrary excitation waveform and an arbitrary antenna orientation.Ph. D.
16
Huynh, Minh-Chau. "Wideband Compact Antennas for Wireless Communication Applications". Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/29853.
Abstract (sommario):
Recent technologies enable wireless communication devices to become physically smaller in size. Antenna size is obviously a major factor that limits miniaturization. In the past few years, new designs of low-profile antennas for handheld wireless devices have been developed. The major drawback of many low-profile antenna designs is their narrow impedance bandwidth. Furthermore, the market trend of personal wireless devices is moving toward a universal system that can be used anywhere and rapid expansion of the wireless communication industry has created a need for connectivity among various wireless devices using short-range wireless links in the Bluetooth operating band to get rid of the cable connections. This requires therefore multiple frequency band operation. In summary, physically small size, wide bandwidth, and high efficiency are the desired characteristics of antennas in mobile systems.
This dissertation presents a comprehensive analysis of a new wide-bandwidth compact antenna, called WC J-pole antenna, covering 50 % impedance fractional bandwidth. A set of guidelines is also provided for a bandwidth-optimized design at any frequency. A few design variations of the proposed antenna are also presented for existing commercial wireless applications.
Efficiency is perhaps the most important characteristic of small antennas for mobile systems. An extension of the Wheeler cap method to moderate-length and wideband antennas is developed to measure quickly efficiency.
The dissertation also provides a review of human operator interaction with handset antennas. Since the proposed antenna is intended to be used in the proximity of human body and in a casing, coupling effects of human body and casing on the antenna characteristics and radio frequency (RF) energy absorption into the human body are investigated.Ph. D.
17
Smith, Christopher Brian. "Wideband dual-linear polarized microstrip patch antenna". [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3162.
18
Lai, Kin-Yue Albert. "A novel antenna for ultra-wideband applications /". The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487685204967095.
19
Gemio, Valero Joan. "Multiband and Silicon Integrated Antennas for Wireless Sensor Networks". Doctoral thesis, Universitat Autònoma de Barcelona, 2011. http://hdl.handle.net/10803/79096.
Abstract (sommario):
Les tecnologies sense fils han provocat una important revolució en el món de les xarxes i serveis de telecomunicació. Han apareguts nous sistemes com els telèfons mòbils d'última generació o les xarxes LAN sense fils que han estat acceptats amb entusiasme per la població. En particular, l'ús de xarxes de sensors (per controlar la temperatura, per a detectar places lliures d'aparcament, etc.) està creixent ràpidament . Aquesta tesi es centra en el disseny d'antenes per a xarxes de sensors distribuïts. En concret s'analitza un sistema on els sensors remots estan connectats a una unitat central utilitzant un radio enllaç operant en la banda ISM de 5,8 GHz, i la unitat central envia la informació recollida a Internet a través d'una connexió WLAN. A la unitat central es necessiten antenes multibanda per cobrir diverses bandes de freqüències amb un únic element radiant. En aquesta tesi es presenten dues solucions per obtenir aquest comportament multibanda: Monopols amb pla de massa fractal i monopols carregats amb ressonadors. S'han fabricat i mesurat diferents prototips que cobreixen les necessitats del sistema. Els sensors han de ser dispositius de reduïdes dimensions i baix cost. Una bona opció per aconseguir aquests requisits és l'ús d'antenes integrades en silici fabricades amb una tecnologia CMOS estàndard. En primer lloc s'analitzen els principals problemes de la integració de l'antena en silici, i a continuació es presenta una possible solució per millorar l'eficiència juntament amb un estudi de la degradació introduïda per altres components quan aquests es fabriquen en el mateix xip que l’antena. Les mesures dels prototips fabricats demostren que la integració de l'antena en la banda de 5,8 GHz és factible, obtenint un abast d'alguns metres.
Cada vegada és una realitat més propera el fet de tenir sensors implantats en el cos. Per aquest motiu, l’última part d'aquesta tesi es dedica a estudiar els efectes del cos sobre antenes situades en el seu interior i avaluar les pèrdues de propagació addicionals introduïdes pels teixits humans.Las tecnologías inalámbricas han provocado una importante revolución en el mundo de las redes y servicios de telecomunicación. Han aparecidos nuevos sistemas, como los teléfonos móviles de última generación o las redes LAN inalámbricas, que han sido aceptados con entusiasmo por la población. En particular, el uso de redes de sensores (para controlar la temperatura, para detectar plazas libres de aparcamiento, etc.) está creciendo rápidamente. Esta tesis se centra en el diseño de antenas para redes de sensores inalámbricos distribuidos. EN concreto se analiza un sistema donde los sensores están conectados a una unidad central utilizando un enlace inalámbrico en la banda ISM de 5.8 GHz, y la unidad central envía la información recogida a Internet a través de una conexión WLAN. En la unidad central se necesitan antenas multibanda para dar servicio a varias bandas de frecuencias con un único elemento radiante. En esta tesis se presentan dos soluciones para obtener este comportamiento multibanda: Monopolos con plano de masa fractal y monopolos cargados con resonadores. Se han fabricado y medido diferentes prototipos que cubren las necesidades del sistema. En los sensores se desean dispositivos de reducidas dimensiones y bajo coste. Una buena opción para lograr estos requisitos es el uso de antenas integradas en silicio fabricadas con una tecnología CMOS estándar. En primer lugar se analizan los principales problemas de la integración de la antena en silicio, y a continuación se presenta una posible solución para mejorar la eficiencia de radiación junto con un estudio de la degradación introducida por otros componentes cuando éstos se fabrican en el mismo chip que la antena. Las medidas de los prototipos fabricados demuestran que la integración de la antena en la banda de 5,8 GHz usando una tecnología CMOS es factible, obteniendo unos alcances de algunos metros incluso cuando la antena se fabrica junto con otros elementos integrados en el mismo chip. Cada vez es una realidad más cercana el hecho de poder tener sensores implantados en el cuerpo. Por este motivo, la última parte de esta tesis se dedica a estudiar los efectos del cuerpo sobre antenas situadas en su interior y evaluar las pérdidas de propagación adicionales introducida por los tejidos humanos.
Wireless technologies have triggered an important revolution in the world of telecommunication networks and services. New systems, such as the latest generation mobile phones or wireless LANs, have appeared being enthusiastically accepted by people. In particular, applications related to remote sensor networks are growing rapidly (for temperature monitoring, the detection of free parking spaces, etc.). This thesis is focused on antenna design for distributed wireless sensor networks. The remote sensors we are considering are connected to a central unit using a wireless link in the 5.8 GHz ISM band and the central unit transmits the collected information to the Internet via a WLAN connection. In the central unit multiband antennas are necessary to cover several frequency bands with a single radiating element. Two solutions to obtain this multiband performance are proposed: fractal-based ground planes and resonator loaded monopoles. Several novel antennas that easily meet the system requirements are manufactured and measured. For remote sensors small dimensions and low costs are desired. The use of silicon integrated antennas fabricated with standard CMOS technology is a good choice to achieve these requirements. First, the main problems of antenna integration are discussed and, then a possible solution to improve the antenna efficiency is presented together with a study of the effects of other elements integrated in the same chip with the antenna. The measurements of the manufactured prototypes demonstrate that antenna integration at 5.8 GHz is feasible, and that system ranges of some meters can be obtained even when the antenna is fabricated together with other elements integrated in the same chip. The possibility of having some of the sensors implanted inside the body will be a reality in the near future, for this reason the particular case of implanted antennas is also analyzed. The last part of this thesis is devoted to study the body effects on antenna performance and evaluate the additional propagation losses introduced by the body tissues.
20
Alsawaha, Hamad Waled. "Synthesis of Ultra-Wideband Array Antennas". Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/54553.
Abstract (sommario):
Acquisition of ultra-wideband signals by means of array antennas requires essentially frequency-independent radiation characteristics over the entire bandwidth of the signal in order to avoid distortions. Factors contributing to bandwidth limitation of arrays include array factor, radiation characteristics of the array element, and inter-element mutual coupling. Strictly speaking, distortion-free transmission or reception of ultra-wideband signals can be maintained if the magnitude of the radiated field of the array remains constant while its phase varies linearly with frequency over the bandwidth of interest. The existing wideband-array synthesis methods do not account for all factors affecting the array bandwidth and are often limited to considering the array factor and not the total field of the array in the synthesis process.
The goal of this study is to present an ultra-wideband array synthesis technique taking into account all frequency-dependent properties, including array total pattern, phase of the total radiated field, element field, element input impedance, and inter-element mutual coupling. The proposed array synthesis technique is based on the utilization of frequency-adaptive element excitations in conjunction with expressing the total radiated field of the array as a complex Fourier series. Using the proposed method, element excitation currents required for achieving a desired radiation pattern, while compensating for frequency variations of the element radiation characteristics and the inter-element mutual coupling, are calculated.
An important consideration in the proposed ultra-wideband array design is that the "phase bandwidth", defined as the frequency range over which the phase of the total radiated field of the array varies linearly with frequency, is taken into account as a design requirement in the synthesis process. Design examples of linear arrays with desired radiation patterns that are expected to remain unchanged over the bandwidth of interest are presented and simulated. Two example arrays, one with a wire dipole as its element and another using an elliptically-shaped disc dipole as the element are studied. Simulation results for far-field patterns, magnitude and phase characteristics, and other performance criteria such as side-lobe level and scanning range are presented.
Synthesis of two-dimensional planar arrays is carried out by employing the formulations developed for linear arrays but generalized to accommodate the geometry of planar rectangular arrays. As example designs, planar arrays with wire dipoles and elliptical-shaped disc dipoles are studied. The simulation results indicate that synthesis of ultra-wideband arrays can be accomplished successfully using the technique presented in this work. The proposed technique is robust and comprehensive, nonetheless it is understood that the achieved performance of a synthesized array and how closely the desired performance is met also depends on some of the choices the array designer makes and other constraints, such as number of elements, type of element, size, and ultimately cost.Ph. D.
21
Choi, Tin Chau. "An ultra-wideband magnetic-electric dipole antenna and a shielded slot antenna". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ38622.pdf.
22
Salehi, Mohsen. "Time-varying Small Antennas for Wideband Applications". Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/25435.
Abstract (sommario):
A desirable goal in wireless communication systems is to achieve a high-rate data transmission through electrically small antennas. However, the overall transmission bandwidth is limited by the antenna size. As a well-known physical limitation, maximum achievable bandwidth of a small antenna is governed by the fundamental limit which defines a lower bound on the antenna quality factor. This limit is a function of electrical size of the antenna and therefore, as the antenna shrinks in size the bandwidth decreases as well. This dissertation presents a new technique to decouple the impedance bandwidth of a high-Q antenna from the information bandwidth in order to provide a wideband data-transmission. This technique controls the natural resonant frequencies of an electrically small antenna in a time-varying fashion such that ultra-fast frequency-shift keying modulation can be achieved regardless of the narrow bandwidth of the antenna. A major advantage of the proposed technique is that the high-Q property of a miniaturized antenna is a desirable design parameter rather than a limiting factor. Therefore, the antenna size can be reduced as much as required. It is shown that if the fundamental resonance of an antenna is shifted in time, the frequency of the near-zone fields which construct the reactive stored energy, changes momentarily and hence, the radiating fields track any instantaneous variation of the antenna fundamental resonance. This characteristic is utilized to employ a single-mode high-Q antenna in the transient state and modulate the fundamental resonant frequency according to the baseband data information. This approach leads to a new class of compact transmitters with a minimized architecture and high data-rate transmission capability.Ph. D.
23
Shapoury, Alireza. "Ultra wideband antenna array processing under spatial aliasing". [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1495.
24
Adamiak, David V. "Transient field visualization for ultra--wideband antenna design". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA374319.
Abstract (sommario):
Thesis (M.S. in Electrical Engineering) Naval Postgraduate School, December 1999."December 1999". Thesis advisor(s): Michael A. Morgan. Includes bibliographical references (p. 89). Also Available online.
25
Karlsson, Magnus. "Ultra-wideband Antenna and Radio Front-end Systems". Doctoral thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10338.
Abstract (sommario):
The number of wireless communication applications increase steadily, leading to the competition for currently allocated frequency bands. Pressure on authorities around the world to permit communications in higher and wider frequency ranges to achieve higher wireless capacity than those existed in the past has resulted in several new specifications. The federal communication commission (FCC) in USA has unleashed the band 3.1-10.6 GHz for ultra-wideband radio (UWB) communications. The release has triggered a worldwide interest for UWB. Other regulatory instances throughout the world have issued use of UWB techniques as well. Capacity issues in form of data rate and latency have always been a bottleneck for broadened wireless-communication usages. New communication systems like UWB require larger bandwidth than what is normally utilized with traditional antenna techniques. The interest for compact consumer electronics is growing in the meantime, creating a demand on efficient and low profile antennas which can be integrated on a printed circuit board. In this thesis, some methods to extend the bandwidth and other antenna parameters associated with wideband usages are studied. Furthermore, methods on how to enhance the performance when one antenna-element is not enough are studied as well. The principle of antenna parallelism is demonstrated using both microstrip patch antennas and inverted-F antennas. Several techniques to combine the antennas in parallel have been evaluated. Firstly, a solution using power-splitters to form sub-arrays that covers one 500-MHz multi-band orthogonal frequency division multiplexing (OFDM) UWB is shown in Paper I. It is then proposed that the sub-bands are selected with a switching network. A more convenient method is to use the later developed frequency multiplexing technique as described in Paper V and VIII. Using the frequency multiplexing technique, selective connection of any number of antennas to a common junction is possible. The characteristic impedance is chosen freely, typically using a 50-Ω feed-line. Secondly, in Paper VIII a frequency-triplexed inverted-F antenna system is investigated to cover the Mode 1 multi-band UWB bandwidth 3.1-4.8 GHz. The antenna system is composed of three inverted-F antennas and a frequency triplexer including three 5th order bandpass filters. In Paper VI a printed circuit board integrated-triplexer for multi-band UWB radio is presented. The triplexer utilizes a microstrip network and three combined broadside- and edge-coupled filters. The triplexer is fully integrated in a four metal-layer printed circuit board with the minimum requirement on process tolerances. Furthermore, the system is built completely with distributed microstrips, i.e., no discrete components. Using the proposed solution an equal performance between the sub-bands is obtained. Finally suitable monopoles and dipoles are discussed and evaluated for UWB. In Paper X circular monopole and dipole antennas for UWB utilizing the flex-rigid concept are proposed. The flex-rigid concept combines flexible polyimide materials with the regular printed circuit board material. The antennas are placed entirely on the flexible part while the antenna ground plane and the dipole antenna balun are placed in the rigid part.
26
Cheng, Shuo-peng, e 鄭碩鵬. "A Reconfigurable Multiband Monopole MIMO Antenna with Wideband Sensing Capability for Cognitive Radio". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/04928024500876707688.
Abstract (sommario):
碩士國立中山大學
電機工程學系研究所
103
Recently, radio spectrum is in high demand as the usage of the spectrum increases day by day at an enormous rate; there is a need to find a solution to efficiently utilize these insufficient resources. Cognitive radio is a huge step towards this goal. Cognitive radio has become a promising technology thanks to its inherent spectrum sensing capability and frequency-agile radio functions for efficient spectrum utilization. In order to achieve a cognitive radio antenna system, we have to design a frequency reconfigurable antenna and a wideband sensing antenna. On the other hand, a multiple-input-multiple-output (MIMO) antenna system is a well-known technique to enhance the performance of wireless communication systems. Quite a few research has been available in each individual field but very few approaches are found in literature where both are combined and utilized. A cognitive radio MIMO antenna is presented in this paper. The proposed antenna consists of two reconfigurable printed monopole antennas and a coplanar waveguide (CPW) fed wideband sensing antenna located between the two antennas. The structure is specially designed for antenna miniature. For multi-channel wireless communication systems, it is essential that the designed multi-antenna would have high isolation between the antenna ports. To this end, the wideband antenna at the middle is utilized as a structure to enhance the isolation of two monopoles. When properly designed, the MIMO antenna can be electronically tuned over the lower ultrawideband (UWB) frequency band (2300–6300 MHz) using two pairs of varactor diodes. The wideband sensing antenna is used to cover a wide range frequency band from 2.2 GHz to more than 7 GHz. The proposed antenna elements develop a complete antenna platform for cognitive radio (CR) applications. The overall size of the antenna is set to be 60 × 40 mm2.
27
Sie, Bing-Yan, e 謝秉諺. "The Research of Microstrip Antenna of Wideband and Inverted F Antenna of Multibands for Mobile Phones Applications". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/99721918014394501882.
Abstract (sommario):
碩士崑山科技大學
電腦與通訊研究所
103
We present a novel antenna of wideband and omnidirectional characteristics. This antenna fed by a microstrip line and tuned by a little “T” matching network generating three resonant frequency points to construct 2-6 GHz wide bandwidth. This antenna can be applied to the applications of 802.11b/g/n/a/p/h and WiMax. This printed antenna etched on a double-sided FR4 board, the top of the FR4 board is the radiator contains a circle and a rectangle metal components, the bottom is a feeding microstrip line and a little “T” matching network. This FR4 board of 1mm thickness and has the size of 45 mm ×22 mm. Simulation is implemented by software HFSS. Design parameters and comparisons of simulated and measured results of antenna will be discussed in this paper. A small-size double-sided three - layers inverted-F antenna suitable to be printed on the system circuit board for LTE 700/2300/2500 MHz, GSM 900 MHz, WLAN 2400/5200/5800 MHz and WiMax 3500/5500 MHz is presented. With mender microstrip line disperses on double-sided and coupled each other to produce enough bandwidth of low-band and multi-band of high-band, but also makes the size of the radiation side of the proposed antenna is 40 × 13mm2. Including the ground plane, the total antenna size is 0.8mm × 87mm × 40mm of the FR4 substrate. This size and performance of this proposed antenna are suitable to the mobile phone.
28
Srivastava, Prateek. "MULTIBAND TRIANGULAR PATCH ANTENNA". Thesis, 2015. http://dspace.dtu.ac.in:8080/jspui/handle/repository/14330.
Abstract (sommario):
In telecommunication, there are several types of microstrip antennas (also known as printed
antennas) the most common of which is the microstrip patch antenna or patch antenna. A patch
antenna is a narrowband, wide-beam antenna.
Microstrip antennas are relatively inexpensive to manufacture and design because of the simple 2-
dimensional physical geometry. They are usually employed at UHF and higher frequencies because
the size of the antenna is directly tied to the wavelength at the resonant frequency. A single patch
antenna provides a maximum directive gain of around 6-9 dB. It is relatively easy to print an array
of patches on a single (large) substrate using lithographic techniques. Patch arrays can provide
much higher gains than a single patch at little additional cost; matching and phase adjustment can
be performed with printed microstrip feed structures, again in the same operations that form the
radiating patches. The ability to create high gain arrays in a low-profile antenna is one reason that
patch arrays are common on airplanes and in other military applications
The most commonly employed microstrip antenna is a rectangular patch. The rectangular patch
antenna is approximately a one-half wavelength long section of rectangular microstrip transmission
line. When air is the antenna substrate, the length of the rectangular microstrip antenna is
approximately one-half of a free-space wavelength. As the antenna is loaded with a dielectric as its
substrate, the length of the antenna decreases as the relative dielectric constant of the substrate
increases. Here a rectangular patch antenna resonating at 2.4 GHz is designed and their reflection
coefficient, radiation pattern & polar plot is drawn & analysed. Now the Triangular patch antenna
working on same resonant frequency is designed which is having less size compared to the
rectangular patch antenna.
The triangular microstrip antenna is one of the shapes of microstrip antennas which have radiation
properties similar to that of the rectangular antenna but with the advantage of being physically
smaller. The simplest of triangular shapes is equilateral antenna which has more directivity with
compact size.
In this project rectangular patch has been designed to operate at resonance frequency of 2.4 GHz for
Wi-Fi application. Then a triangular patch antenna of same resonating frequency is designed. It has
been seen from the result that the size required for the triangular antenna to resonate at the same
frequency is less as compared to rectangular patch antenna.
Then triangular slots have been made in the same triangular patch antenna so that it is converted
into the fractal antenna and the design is simulated. The result obtained for two fractal geometry
shows that the return loss of the antenna at 2.4 GHz is less as compared to the same dimensions of
triangular patch antenna. Fractal antenna is having many advantages over the simple patch antenna
like miniaturization, better input impedance matching & wideband / multiband behaviour.
A new triangular multiband patch antenna has been designed to operate at resonant frequencies 1.1
GHz, 2 GHz & 3 GHz.. again the triangular slots are cut in this design to make it fractal antenna so
we get the lower return loss at resonant frequencies.Dr. Priyanka Jain (Assistant Professor) Department of Electronics & Communication Engineering
29
KUO, Chun-Yi, e 郭俊逸. "Design of Multiband Planar Antenna". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/94193761606288531922.
30
YUEH, WANG CHUNG, e 王忠嶽. "Multiband Antenna Simulation and Design". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/34012930120670476862.
Abstract (sommario):
碩士大葉大學
電信工程學系碩士在職專班
97
This thesis presents the design of two printed dipole antennas. These two antennas were developed to produce multiple resonant bands so as to support multi-standard wireless-communication products, such as laptop computers, personal digital assistances (PDAs), and mobile wireless networking devices. These standards include GSM 900 MHz (Global System for Mobile Communications; 870-960 MHz), DCS 1800 MHz (Digital Communication System; 1710-1880 MHz), PHS 1900 MHz (Personal Handy-Phone System; 1890-1915 MHz), WCDMA 2100 MHz (Wideband Code-Division Multiple Access; 2100-2170 MHz), WiFi 2.4 GHz (Wireless Local-Area Network; 2400-2483 MHz; also called WLAN), and WiMAX 2.6 GHz (Worldwide Interoperability for Microwave Access; 2.5-2.7 GHz). Note that the antennas presented here were originally designed for FarEastone telecommunications company (FET), for which the required GSM and DCS bands are in the ranges of 870-890 MHz and 1800-1880 MHz, respectively. For these two standards, the designed antennas must cover these two frequency bands, instead of 870-960 MHz and 1710-1880 MHz. For cost saving, the antennas were printed on FR4 substrates with a thickness of 1 mm. Numerical simulation was carried out using Zeland’s IE3D, a full-wave electromagnetic simulator. Before antenna prototypes were constructed and measured, the structural parameters of the designed antennas were varied iteratively until antenna performances are close to the required specifications. The first antenna type is a co-directionally meandered dipole antenna, in which the structures in the two arms of the antenna are almost symmetric with respect to the feeding point. The second antenna type is a bi-directionally meandered dipole antenna, in which the structures in the two arms are nearly anti-symmetric with respect to the feeding point. It is observed that the bi-directionally meandered dipole antenna is slightly more compact than the co-directionally meandered one.
31
Chen, Wen-Wang, e 陳文旺. "Design of Multiband Operation Antenna". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/58373468536045029929.
Abstract (sommario):
碩士高苑科技大學
電子工程研究所
98
The paper presents study of multi-band monopole antenna, which utilize simulation software Ansoft HFSS 10 to measure the antenna return loss which under -10dB with Smith chart and coincidence to the standard of range, and the multiband ( DVB、 GSM、GPS、DCS、PCS、Bluetooth、WLAN and WiMAX ) are contained and applied. The monopole antenna uses slot、meanderings、parasitic antenna、loop、reflecting board and “ PIFA ”, those techniques attempted to encourage each band effectively. Due to the design of antenna on the base, some slots are used the impedances of loops to compensate and close the impedances of resistors, also the meanderings is used to extension the length if antenna to fit the wavelength, parasitic antenna is used to gain the bandwidth in every each band, than this three prescriptions are inspired to lower noise interrupted at 1.6 GHz ~ 1.7 GHz、2.0 GHz ~ 2.2 GHz and 2.9 GHz ~ 3.2 GHz. At present, the laptop is miniaturization that ever, and the multiband monopole antenna could meet the requested. We will double the loop of antenna that we would use inside the limitation of space of laptop ,and it would be work by double the wave length, double the emerge between the frequencies of low-band and medium-band . The design of “ PIFA ” makes the bandwidth of high-band more wider, cause the Result of match of bandwidth between low-band and high-band is more than 25% ( above 500 MHz ) is fit the definition of Ultra Wide Band ( UWB ).
32
Siao, Sin-long, e 蕭新朧. "Miniaturized GPS chip antenna and multiband monopole antenna". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/09486805850704632333.
Abstract (sommario):
碩士國立臺灣科技大學
電機工程系
97
For future communication systems, to simultaneously meet various requirements such as low profile, compact size, light weight and easy fabrication, the dimension consideration of antenna design is a very critical part. The radiation performance of the antenna also directly affects the received signal and communication quality. Therefore this thesis proposes a miniature GPS antenna to be built in the mobile phone, PDA and smart phone for obtaining the satellite signals. A commercial EM solver, HFSS has been utilized to design prototype and investigate the performance variation for antenna located at different positions in the test board. Moreover, a multi-band monopole antenna is also presented to integrate more wireless access functions. The operating band of the proposed antenna is composed of GSM, DCS, PCS, UMTS, Bluetooth, WLAN、WiMax, Hyper LAN, WWAN and WiFi. As to achieve a better radiation performance, the antenna also employs two back-strips to enhance more resonant frequencies and flexibly adjust input impedance in this study.
33
FAN, CHIH-WEI, e 范智偉. "Design of Multiband Coplanar slot antenna". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/63944947429000173611.
Abstract (sommario):
碩士明新科技大學
電機工程系碩士班
104
Coplanar slot antennas with three different shapes of radiator, comb, flag and polygon are designed in this thesis. Changing the element of comb radiator, the suitable size parameters are obtained from simulation. The simulated results are used to produce containing WLAN and LTE frequency bands antenna. Changing ground area of coplanar flag type radiator slot antenna is used to shift the impedance bandwidth to lower frequency. It can also be used to produce containing WLAN and LTE frequency bands antenna. Changing the bevel of polygonal radiator is used to get better size parameters. It can also be used to produce containing WLAN and LTE frequency bands antenna. In this thesis, the glass fiber (FR4) substrate is adopted to fabricate the antenna and IE3D electromagnetic simulation software is used for analyzing the designed antenna. The fabricated comb-radiator slot antenna can be applied to 1.8 / 2.4 / 2.6 / 3.6 GHz bands. The fabricated flag-radiator slot antenna can be applied to 0.7/0.9/1.8/2.4/2.6/3.6 GHz bands. The fabricated polygon-radiator slot antenna can be applied to 1.8 / 2.4 / 2.6 / 3.6 / 4.9 / 5 / 5.1 / 5.8 / 5.9 GHz bands. The obtained polygonal radiator coplanar slot antenna which peak gains are 2.31dBi, 3.76 dBi, 3 dBi, 3.31 dBi, 3.03 dBi, 3.04 dBi, 4.21 dBi, and 4.37 dBi at 1.8 GHz, 2.4 GHz, 2.6 GHz, 3.6 GHz, 4.9 GHz, 5 GHz, 5.8 GHz, and 5.9 GHz, respectively. Keywords: Long term evolution, Coplanar waveguide antenna, Comb-type radiator, Flag-type radiator, Polygonal radiator
34
Chao, Chun-heng, e 趙君恒. "Study of multiband slot antenna designs". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/2gzp58.
Abstract (sommario):
碩士逢甲大學
電機工程所
100
The thesis focuses on the design of slot antennas. Here, two slot antennas were proposed with different fed-techniques that allow the antennas to operate at different applications. A microstrip-fed slot antenna design for WLAN（2.4/5.2/5.8 GHz）application was initially proposed. In order to achieve dual-band operation, three slots were embedded into the ground plane that located beneath the microstrip feed-line. Two of the loaded slots were of step-impedance (SI) designs, and the third one was an inverted L-shaped slot. The proposed antenna exhibited 10-dB bandwidth of 607 MHz (24.78 %) and 1102 MHz (26.83 %) for the lower and upper operating bands, respectively. Besides demonstrating bi-directional radiation characteristic, steady gain variation and at least 66 % of efficiency were also measured. The second proposed antenna was a coplanar waveguide (CPW)-fed square-ring slot antenna with dual-band operation for WLAN (2.4/5.2/5.8 GHz) and WiMAX (2.3/2.5/3.5/5.7 GHz) applications. The lower operating band was excited by the square-ring with asymmetric ground plane, and the upper operating band was induced by a stub-protruded monopole and a double-bent stub loaded into the ground plane. The antenna has small structure and exhibited bi-directional radiation characteristics. In addition, it also demonstrated steady gain variation within the WLAN and WiMAX operating bands.
35
TIAN, CHANG-FU, e 田章甫. "Design of Multiband Planar Dipole Antenna". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/9tuy5f.
Abstract (sommario):
碩士明新科技大學
電機工程系碩士班
105
In this thesis, FR4 substrate and IE3D software are used to design multi-band antennas, including comb shaped with rectangular arm dipole antenna which can be applied to 1.8GHz,2.4GHz,2.45GHz and 2.6GHz frequency bands, comb shaped with needle arm dipole antenna which can be applied to 1.8GHz,2.4GHz,2.45GHz and 2.6GHz frequency bands, comb shaped with unequal rectangular arm dipole antenna which can be applied to 1.8GHz,2.4GHz,2.45GHz and 2.6GHz frequency bands , and comb shaped slot antenna which can be applied to 0.7GHz 0.9GHz and 1.8GH frequency bands. In this study, the size parameters of comb shaped planar dipole antenna are changed to observe the impacts on antenna characteristics. After simulation, the better parameter values of dipole antenna are obtained and can be used in GPS,RFID,WLAN and LTE frequency bands. The suitable size parameter L5=26.75mm of the comb shaped with uequal rectangular arm dipole antenna is obtained from simulated results. The proposed antenna can be used in RFID, WLAN and LTE frequency bands. The comb arm size parameters of the dipole slot antenna are adjusted to observe the variations with respect to the bandwidth, resonant frequency and gain of the proposed antenna. The better size parameters L5=29mm and L6=15mm are obtained to fabricate the comb dipole slot antenna which can be used in LTE 0.7GHz, LTE 0.9GHz and LTE 1.8GHz frequency bands. The proposed multiband dipole antennas by changing size parameters can be applied to GPS, WLAN, RFID and LTE frequency bands, respectively. Key words：planar dipole antenna、comb shaped rectangular arm、needle arm、WLAN、LTE
36
Hsieh, Yuan-pu, e 謝沅圃. "Multiband CPW-fed slot antenna design". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/10018352714300872868.
Abstract (sommario):
碩士逢甲大學
電機工程所
98
The thesis focuses on the design of slot antennas and proposes a series of coplanar slot antennas with different structures by using a variety of design methods to meet different applicable frequencies. First, the thesis proposed a dualband coplanar triangle ring slot antenna. The lower band (2.34-2.8 GHz) is excited by the triangular ring slot and capacitive load, while the higher frequency band is excited by two T-slots embedded in the triangular radiation element, and its wide impedance bandwidth (5.15-6.9 GHz) is also due to the capacitive load. This novel antenna can be used in the WLAN 2.4/5.2/5.8 GHz. Then, a coplanar circular ring slot antenna design is proposed, and similar capacitive loading technique from the previous triangle ring slot antenna is used, so that the excited lower resonant mode can operate in the 2.4 GHz band. By inserting a pair of arc-shaped parasitic strip, a 5.8 GHz resonant mode is excited and by combining with the 4.5 GHz resonant mode, a broadband operation that covers the 5.2, 5.5 and 5.8 GHz bands is achieved. Besides demonstrating a bi-directional radiation characteristic, this antenna also shows steady gain variation in the WLAN 2.4/5.2/5.8 GHz operation. Finally, a coplanar rectangular slot antenna design is proposed for WLAN 2.4/5.2/5.8 GHz and WiMAX 2.6/3.5/5.5 GHz operations. The two wideband operations are excited by embedding two inverted L-shaped slot with dissimilar sizes into the rectangular radiating element. This novel antenna also shows steady gain variation in the WLAN and WiMAX operations.
37
Zeng, Jian-Hong, e 曾建弘. "Design of Multiband Planar MIMO Antenna". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/23593305021202076714.
Abstract (sommario):
碩士龍華科技大學
電子工程系碩士班
102
This thesis presents a compact multiband planar MIMO antenna that covers the standards of the Global System for Mobile (GSM), Long Term Evolution (LTE) and Ultra-Wideband (UWB). The MIMO antenna contains two printed back-to-back multiband monopole elements with a closed distance of one-tenth wavelength of 900MHz. The element in the MIMO antenna is structured by merging an UWB antenna and a parasitic multi-loaded winding line monopole that is capable of providing the broadband coverage for the standards of the GSM, LTE and UWB. The size of the antenna element without ground plane was 30mm x 28mm. Because of the asymmetric element radiation pattern and, thus the MIMO antenna exhibits the desirable low mutual coupling effect at 900MHz frequency band. Further, a pair of meta-material resonator is constructed and placed between antenna elements in order to improve the correlation coefficient at 1.8GHz and 2.2GHz bands. The measured isolations of the prototype are less than -20 dB in all operating frequency bands.
38
Chen, Zhi-Ying, e 陳智穎. "Design of Printed Multiband LTE Antenna". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/u79ves.
Abstract (sommario):
碩士元智大學
通訊工程學系
106
With the rapid development of cellular communication and higher quality demands by the customers, the communication system has evolved to the fourth generation. Supporting multiple frequency bands in different regions becomes a must for the modern smart phone. In this thesis, a multiband printed antenna for Long-Term-Evolution(LTE) is presented. The proposed antenna is based on a ultra-wide band (UWB) planar triangular monopole antenna (PTMA) and have a volume of 60×100×1.6〖mm〗^3. The size of a PTMA is first enlarged to cover the target LTE multiple bands and a mesh consisting of rectangular metal patch is applied to the additional space above the radiator. The orthogonal array (OA) method is employed to decide the distribution of these grids. Although the OA method doesn’t find the mesh distribution that will cover the LTE lowest band from 700MHz to 960MHz, but it does provide a initial mesh distribution that covers half of this band. Based on the initial pattern calculated by using OA, multiple current path approachs are used to meet the requirements of the lowest LTE band. With several modifications to further improve the impedance matching at higher frequence band, the final antenna is implemented. This S11 of the final antenna matchs the requirement of the LTE bands with two return losses. The bandwidth of the lower band is 262MHz(698-960MHz) with 6dB return loss and that of the higher band is 2590MHz(1410-4000MHz) with 10dB return loss. The measurements of the antenna in chamber, indoor, outdoor, and handled by hands are also presented in this study.
39
YU, JIA-YI, e 余家一. "Designs on Multiband Antenna for LTE Applications". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/02510455459107705088.
Abstract (sommario):
碩士明新科技大學
電機工程系碩士班
104
In this thesis, coplanar waveguide feed and symmetrical ground are used to design the antenna. Chapter 3 and chapter 4 are themed with miniaturization, broadband and multi-band. Chapter 5 is focused on designing the antenna’s operating frequency bands which cover LTE 0.7/0.9/1.8/2.6GHz and WLAN 4.9GHz bands. In chapter 3, the radiator’s notch size parameter L5, the ground size parameters L2 and W2, and height of needle-shaped radiator H are changed to design the antenna which peak gain are 1.41dBi, 2.93dBi, 3.30dBi, 3.19dBi, 1.99dBi, 3.72dBi, 6.28dBi and 4.15dBi at 1.8GHz, 2.4GHz, 2.45GHz, 2.6GHz, 3.5GHz, 3.6GHz, 5.8GHz and 5.9GHz, respectively. In chapter 4, the parameters including needle-shaped size parameter of radiator W3, feed copper foil size parameter of ground L3, and notch size parameter of ground C2 are changed to design the antenna which peak gain are 3.60dBi, 1.80dBi, 2.80dBi, 2.88dBi, 2.48dBi, 2.14dBi, 2.41dBi, 2.76dBi, 4.96dBi and 3.98dBi at 1.8GHz, 2.4GHz, 2.45GHz, 2.6GHz, 3.5GHz, 3.6GHz, 4.9GHz, 5.1GHz, 5.8GHz and 5.9GHz, respectively. In chapter 5, the upper copper foil size parameter of ground L2 and the size parameters of radiator’s notch W6 and W7 are changed to design the antenna which peak gain are 3.01dBi, 3.08dBi, 1.61dBi, 2.64dBi and 4.36dBi at 0.7GHz, 0.9GHz, 1.8GHz, 2.6GHz and 4.9GHz, respectively. The antennas designed in this study can be used in LTE, WLAN, RFID, GSM, and Bluetooth bands.
40
Pan, Po-Yu, e 潘柏宇. "Study of Multiband Monopole Antenna for LTE". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/3jrg8n.
Abstract (sommario):
碩士義守大學
電機工程學系
102
Antenna device needs to be able to send and receive signals in wireless network communications. As technology advances, Mobile band from the early GSM 900/1800 (2G) and now widely used cellphone multimedia transmission UMTS 2100 (3G) and is developing LTE 700/900/1800/2600 (4G). This paper presents the multiband antennas applicable for LTE, this antenna have three- frequency band, the main design principles combined with G-type monopole antenna and L-type monopole antenna, with two different shapes monopole excitation frequency to complete. First, use of G-type monopole antenna structure resonance of 700MHz/1800MHz modal, then by adding L-shaped monopole antenna structure to increase the resonance path length, in addition to produce 2600MHz modal. The design frequency bands are for LTE 700/1800/2600. The simulator HFSS is employed for simulation and results show that 700/1800/2600MHz are included in the band.
41
Chien, Shih Chieh, e 簡世杰. "Wideband and Multiband Millime-ter-Wave Front-End Circuits". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/45488008294814444352.
Abstract (sommario):
碩士國立清華大學
電機工程學系
103
With the high demands of the high-speed point-to-point communications and real time multimedia streaming, increasing communication standards are proposed at the millimeter-wave band. Fully integrated wideband and multi-band voltage-controlled oscillators (VCOs), low-noise amplifiers (LNAs) and power amplifiers (PAs) have gained momentum in the past few years. However, the designs of the wideband and multi-band front-end circuits are complicated and challenging in order to achieve high performance on the specifications such as the phase noise of the VCO, the noise figure of the LNA and the efficiency of the PA. In this thesis, fundamental of these circuits are first revisited followed by the design methodologies and discussion of five novel works. Two millimeter-wave wideband and multi-band VCOs are introduced with a high order tank, a switch resonator, and digital controlled artificial dielectric (DiCAD) transmission line. A unique architecture with a 4th-order tank in a dual-band input matching network and a bandpass filter with a notch is proposed to achieve a concur-rent dual-band LNA. Finally, two PAs are designed to provide the concurrent du-al-band operation by leveraging a built-in notch of a transformer that couples from adjacent stages.
42
Lee, Meng-Che, e 李孟哲. "A Novel Method for Multiband Filtering Antenna Design". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/n72zq3.
Abstract (sommario):
碩士國立交通大學
電信工程研究所
103
Filtering antenna is a single component which integrated bandpass filter and antenna in one module to achieve miniaturization and improve performance of microwave front ends. Most of the filtering antenna literatures operate in single band because the method they use is too difficult to design in multiband, especially in wideband. The integration approach they use is to substitute the last resonator and the load impedance of the bandpass filter with an antenna. As there is no literature about triple-band filtering antenna, it is a good topic for worthy discussion. A novel compact triple-band filtering antenna operated at 2.45 / 3.5 / 5.5 GHz with wide bandwidth is proposed in this thesis. We use a different kind of method to design multiband filtering antenna. In order to achieve triple-band filtering antenna, we need to design triple-band bandpass filter first. The proposed triple-band bandpass filter is composed of stepped-impedance resonator (SIR) and uniform-impedance resonator (UIR). Second, we changed the energy direction by using inverted-U shape structure for integrating antenna. Using wide slot fork-shape antenna as our radiator is the key point of this triple-band filtering antenna. This filtering antenna is realized by 33 × 23 mm2. The design of the filtering antenna and the experiment result will be given and discussed in detail in the thesis.
43
Chen, Weichuan, e 陳韋銓. "Design of Compound Multiband Antenna for Portable Devices". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/65785114206860943501.
Abstract (sommario):
碩士明志科技大學
電子工程研究所
100
In this thesis, we have proposed a compound multiband antenna design for portable devices. The designs are composed of different monopole antenna models to composition small size, simple structure, multi-band operation of the monopole antenna for the mobile devices and USB dongle. The advantages of the proposed antennas overcome the problem of insufficient bandwidth and meet the radiation efficiency of the industry standards. The used designs of compound multiband antennas can cover the wide-band operation of GSM850/900/1800/1900/UMTS and ISM/WiMAX, respectively. Above all, the experimental results show that the radiation efficiencies of the proposed antennas are more than 50% and satisfy the requirements of industry standards.
44
Wang, Tai-Ming, e 汪泰名. "The Study in Multiband Elliptical-truncated Microstrip Antenna". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/72692904210775834297.
Abstract (sommario):
碩士中華技術學院
飛機系統工程研究所
96
In this thesis, a multiband elliptical patch microstrip antenna that have simple structure and was analyzed and optimized by using the IE3D software is proposed. The proposed antenna uses elliptical metal patch and coupling feed line on the FR4 printed board, in addition to increasing frequencies of antenna and improving whole performance by using shorting ping. It operates at GSM (880–960 MHz)、DCS (1710–1880 MHz)、PCS(1880–1990 MHz)、UMTS (1900–2170 MHz)、WiBro (2300–2390MHz)、Bluetooth (2.4–2.48 GHz).
45
YANG, YI-YUNG, e 楊義勇. "Multiband antenna designs for applications in smart watches". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/58834346466725631023.
Abstract (sommario):
碩士國立高雄師範大學
光電與通訊工程學系
104
Three novel designs of the multiband antenna designs for applications in smart watches are presented in this thesis. The first proposed antenna has a simple open slot structure excited by a microstrip feedline. The achieved impedance bandwidths of the proposed antenna can cover the Bluetooth/Wi-Fi 2.4 GHz band (2400 ~ 2484 MHz). For the spacing 2 mm between the antenna and wrist, the antenna efficiency is 25% ~ 29%. The second proposed antenna consists of an open slot, a tuning slot and a two-branch microstrip feedline integrated with a chip capacitor. The achieved impedance bandwidths can cover the GPS 1.6 GHz bands (1560 ~ 1610 MHz) and Bluetooth/Wi-Fi 2.4 GHz band. The antenna efficiencies are 21% ~ 27% at 1.6 GHz band and 24% ~ 27% at 2.4 GHz band. As for the third proposed antenna, a triple-branch PIFA is used. The bandwidths of the antenna can cover the GSM900 band (880 ~ 960 MHz), GSM900 band (1710 ~ 1880 MHz), and Bluetooth/Wi-Fi 2.4 GHz band.
46
Chan, Chao-Kai, e 詹兆凱. "A Coupling Slot Multiband Antenna for Mobile Phones". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/65325308419270386965.
Abstract (sommario):
碩士國立交通大學
電信工程系所
97
A novel internal multiband slot antenna for mobile phone applications is presented. The antenna consists of two L-shaped slots of different lengths cut at the edge of the system ground and added a parasitic strip. It is shown that with a proper design, the two L-shaped slots can generate the operating bandwidths by coupling effect. And the parasitic strip is electromagnetically coupled and excited by the slot to generate the WLAN band. Hence, three elements can separately control the operating frequencies of the three excited resonant modes, which generate the three bands centered at about 900, 2100 and 5200 MHz to cover the GSM/DCS/PCS/UMTS/Bluetooth/WiMAX/WLAN bands. Furthermore, the antenna has a simple planar structure and occupies a small area of 35×22mm2. Good radiation characteristics are obtained over the three operating bands. The design details for the proposed antenna are described, and the experimental results of the antenna performances are presented and discussed.
47
Wang, Yi-Shiang, e 王奕翔. "Planar Multiband Antenna Designs for Tablet Computer Application". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/58632872871716047666.
Abstract (sommario):
碩士國立高雄海洋科技大學
電訊工程研究所
101
In this dissertation, two internal multiband antenna designs for tablet computer devices are proposed. First, by adding an internal printed loop as the LC matching circuit, the antenna design provides the impedance bandwidths of 262/1610 MHz for the application of LTE/WWAN system. The proposed uniplanar antenna reduces the antenna size by at least 30% since the overall antenna size is only 40 × 15 × 0.8 mm3. Meanwhile, the measured peak gains and antenna efficiencies are about 2.81/4.79 dBi and 79/87 %, respectively. Next, the second antenna design proposes a G-shaped coupled feed structure to obtain the impedance bandwidth of 264/1046 MHz across dual operating bands to meet the specifications of the fourth generation mobile communication system. Furthermore, with more than 40% antenna size reduction, the measured peak gains and antenna efficiencies are about 3.61/5 dBi and 67/67 %, respectively. Additionally, the analysis of the body specific absorption rate (SAR) for two proposed monopole antennas are discussed and less than 1.6 W/kg for 1-g body tissue. Finally, the discussions for MIMO operations of both two proposed antenna designs are presented with good isolation.
48
Gu, Jiun-Peng, e 辜駿鵬. "An LTE smart mobile antenna with multiband operation". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/36566617569139439907.
Abstract (sommario):
碩士國立臺灣海洋大學
電機工程學系
101
Two kinds of LTE smart mobile antenna with multiband operation are proposed to work in the bands of LTE, GSM, DCS, PCS, PHS, UMTS, Bluetooth, and WLAN. The initial design consists of a three-dimensional meandering monopole antenna constructed on the extended region of the PCB to reduce the space and also acting as the main radiator operating in the bands of LTE, DCS, and PCS, PHS, and UMTS. Subsequently, by adjusting the coupling between the monopole antenna and the shorted stub, the GSM band is added and the impedance matching in the band of LTE is improved. Finally, an additional shorted stub is constructed to radiate in the WLAN. The numerical results show that the -6dB return-loss bandwidths are from 0.7 GHz to 0.985 GHz (0.285 GHz, 34%) for the lower band and from 1.64 GHz to 2.535 GHz (0.895GHz, 43%) for the higher band. The corresponding measured data are from 0.7 GHz to 1.03 GHz (0.33 GHz, 38%) for the lower band and from 1.64 GHz to 2.55 GHz (0.91 GHz, 43%) for the higher band. A second antenna is designed by replacing the coupling stub in the first antenna with a wider one. The wider stub is placed on the top of the substrate so that more space is available on the ground plane, resulting in more suitable application in the mobile device. The numerical results show that the -6dB return-loss bandwidths are from 0.7 GHz to 0.9668 GHz (0.2688 GHz, 27.2%) for the lower band and from 1.5953 GHz to 2.6 GHz (1.0047 GHz, 47%) for the higher band. The corresponding measured data are from 0.688 GHz to 1.03 GHz (0.315 GHz, 39.8%) for the lower band and from 1.61 GHz to 2.65 GHz (1.04 GHz, 48.8%) for the higher band.
49
Wan, Yu-Chang, e 萬育章. "LTE Multiband Antenna Design for Wireless Network Applications". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/7nrv6y.
Abstract (sommario):
碩士國立臺北科技大學
電子工程系
106
To adapt the trend for the 4G LTE ( 4 Generation Long Term Evolution), this research paper is going to present the antenna for supporting 4G multi-band. Its applied on the wireless router and makes the channel selection more flexible with the WiSprys RF-MEMS technology. Eventually, to execute a system of the MIMO and adjust the high isolation. In this case, antenna is made by the techniques of the FR4 PCB. To meet the requirement from the different telecommunication operators, the author uses CPW-fed Monopole antenna which can apply the LTE Band 28/8/3/7. The traditional antennas generally lose the gains for the bandwidths. In order to overcome that, the author uses WiSprys RF-MEMS technology to make more advantageous Impedance matching. In the measuring results, the operating frequency can actually cover LTE Band 28/8/3/7, that covering the Band of the 4G FDD-LTE. The radiation pattern which is closed to Omni-direction is suitable for the antenna for wireless router. In LTE Band 28, the measured peak radiation gain and efficient are 0.08 dBi and 30 %. In LTE Band 8, the measured peak radiation gain and efficient are 0.57 dBi and 40 %. In LTE Band 3, the measured peak radiation gain and efficient are 1.61 dBi and 50 % and in LTE Band 7, the measured peak radiation gain and efficient are 2.99 dBi and 55%. On the other hand, the calculated results of MIMO system of the envelope correlation coefficient in all of the operating frequency band meet isolation requirement.
50
謝維庭. "Multiband Antenna for WWAN/LTE Mobile Phone Applications". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/fzfmb3.
Abstract (sommario):
碩士逢甲大學
通訊工程學系
106
This thesis focuses on multi-band antennas for handheld devices including smart phones and tablet computer. There are three antennas proposed in this research. The main structures of the antennas are monopole antenna and slot antenna. The first antenna is a multi-band antenna for smart phone. It can provide LTE 700/2300/2500 (698~787, 2300~2400, 2500~2690 MHz), GSM 850/900/1800/1900 (824~894, 890~960, 1710~1880, 1850~1990 MHz), UMTS 2100 (1920~2170 MHz) and WLAN 2400 (2400~2488 MHz). The antenna consists of three branches monopole antenna and a shorting strip with a matching capacitor. In order to reduce the overall antenna size, a 3-dimensional structure is designed. The volume of the proposed antenna is 70×8×3