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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.
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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.
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Benomar, Ahmed. "Etude des Antennes à Résonateurs Diélectriques. : Application aux Réseaux de Télécommunications." Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0025/document.
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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…
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Garcia, Gamez Laura. "Analysis and design of compact antennas in cavity based on metasurfaces for multiband GNSS applications." Thesis, Rennes 1, 2020. http://www.theses.fr/2020REN1S014.
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Les systèmes de navigation par satellites globaux (GNSS) sont aujourd'hui largement utilisés pour pléthore d'applications civiles ou pour la défense, incluant la navigation de plateformes volantes ou roulantes. Galileo, GPS ou Glonass sont trois des constellations GNSS considérées dans cette thèse. L'objectif de ce travail est de développer des antennes compactes capables de couvrir plusieurs bandes GNSS ; trois autour de 1575 MHz dans un premier temps (L1, G1, E1), puis la totalité de la bande GNSS ([1164-1610] MHz). Ces antennes sont destinées à être intégrées dans des projectiles, constitués principalement de métal. Pour cette raison, l'antenne doit être intégrée dans une cavité métallique pour ne pas affecter les propriétés aérodynamiques ni la stabilité mécanique du porteur. Intégrer des antennes imprimées dans des cavités métalliques offre plusieurs avantages : la miniaturisation, l'isolation ou la réduction des ondes de surface. Néanmoins, cela amène également une réduction importante de la bande passante. La solution immédiate pour limiter cet effet est d'agrandir la dimension de la cavité. Cependant, cette approche ne peut pas être appliquée aux nombreux cas où le porteur impose des limitations d'encombrement. Au vu des spécifications ci-dessus, l'emploi d'une antenne imprimée basée de métasurfaces est proposé et étudié, d'autant plus que des résultats antérieurs ont montré que des structures d'antennes classiques ne peuvent répondre aux spécifications demandées. Les objectifs de cette thèse sont de concevoir et de caractériser des antennes à polarisation linéaire et à polarisation circulaire couvrant plusieurs bandes GNSS. La polarisation linéaire est considérée pour les premières études, car ces antennes ne sont pas destinées à être utilisées dans un environnement souffrant de trajets multiples. La polarisation circulaire est considérée dans un second temps. Finalement, l'extension de la bande passante à la globalité de la bande GNSS est considéréeGlobal Navigation Satellite Systems (GNSS) are widely used today for a plethora of civil and defense applications, including navigation of flying or moving platforms. Galileo, GPS or Glonass are three of the GNSS constellations considered in this thesis. The aim of this work is to develop a compact antenna, which is able to cover multiple GNSS bands: three around 1578 MHz (L1, G1, E1) in a first time and the whole band ([1164-1610] MHz) in a second time. These antennas are intended to be integrated into projectiles mainly constituted of metal. For this reason, the antenna must be embedded in a metallic cavity to not affect the carrier aerodynamic properties and nor its mechanical stability. Integrating microstrip antennas in metallic cavities offers several advantages, like miniaturization, isolation or surface wave reduction; however, this leads to a drastic reduction of the antenna bandwidth. The most straightforward solution to circumvent this limitation consist in enlarging the metal cavity size. Nonetheless, this approach cannot be applied in many cases when the carrier imposes stringent dimensional limitations. Owing to the above-mentioned specifications, the use of a metasurface-inspired microstrip antenna is proposed and investigated, since previous results have demonstrated that classical antenna structures do not comply with the requirements. The objectives of the thesis are to design and characterize linearly-polarized and circularly-polarized antennas covering multiple bands of GNSS. Linear polarization is considered for the first studies, as these antennas are not intended to be used in an environment with multi-path signals. Circular polarization is addressed in a second time. Finally, the extension of the bandwidth to the whole GNSS bands is considered
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Ikram, Amna. "Design and development of a multiband loop antenna for cellular mobile handsets." Thesis, University of Gävle, Department of Electronics, Mathematics and Natural Sciences, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-7412.
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Desjardins, Jason. "Reconfigurable Dielectric Resonator Antennas." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19838.
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With the increasing demand for high performance communication networks and the proliferation of mobile devices, significant advances in antenna design are essential. In recent years the rising demands of the mobile wireless communication industry have forced antennas to have increased performance while being limited to an ever decreasing footprint. Such design constraints have forced antenna designers to consider frequency agile antennas so that their behavior can adapt with changing system requirements or environmental conditions. Frequency agile antennas used for mobile handset applications must also be inexpensive, robust, and make use of electronic switching with reasonable DC power consumption.
Previous works have addressed a number of these requirements but relatively little work has been performed on frequency agile dielectric resonator antennas (DRAs). The objective of this thesis is to investigate the use of DRAs for frequency reconfigurability. DRAs are an attractive option due to their compactness, very low losses leading to high radiation efficiencies (better than 95%) and fairly wide bandwidths compared to alternatives. DRA’s are also well suited for mobile communications since they can be placed on a ground plane and are by nature low gain antennas whose radiation patterns typically resemble those of short electric or magnetic dipoles.
One way to electronically reconfigure a DRA, in the sense of altering the frequency band over which the input reflection coefficient of the antenna is below some threshold, is to partially load one face of the DRA with a conducting surface. By altering the way in which this surface connects to the groundplane on which the DRA is mounted, the DRA can be reconfigured due to changes in its mode structure. This connection was first made using several conducting tabs which resulted in a tuning range of 69% while having poor cross polarization performance. In order to address the poor cross polarization performance a second conducting surface was placed on the opposing DRA wall. This technique significantly reduced the cross polarization levels while obtaining a tuning range of 83%. The dual-wall conductively loaded DRA was then extended to include a full electronic implementation using PIN diodes and varactor diodes in order to achieve discrete and continuous tuning respectively. The two techniques both achieved discrete tuning ranges of 95% while the varactor implementation also had a continuous tuning range of 59% while both maintaining an acceptable cross polarization level.
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Perros, Sotirios Georgios. "The design and evaluation of transmit and receive antennas for an ionospheric communications probe system: A. Multiband Dipole Antenna." Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/23621.
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Approved for public release; distribution is unlimitedThis thesis reports the design, performance evaluation and construction of a transmitting antenna for an HF communications probe system. A short range ionospheric communication link between Monterey, CA, (transmit site) and San Diego, CA, (receive site) was established to test the software and hardware of this probe system. The Multiband Dipole Antenna was selected as the more practical antenna for this link, using less real estate and support structure than other alternatives. The antenna was constructed and installed at the NPS beach site where the ground constants were measured accurately. Numerical Electromagnetics Code (NEC) analysis and measurements show that the antenna operates with low input VSWR ( < 1.5), is insensitive to electrical ground characteristics and has excellent radiation patterns for short range ionospheric communication links. Based on the observed signal strengths at San Diego, the antenna appears to be performing very well.
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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.
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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.
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Lominé, Jimmy. "Étude d’une antenne vectorielle UHF multibande appliquée à la goniométrie 3D." Thesis, Toulouse, INPT, 2014. http://www.theses.fr/2014INPT0096/document.
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De nos jours, il existe de nombreuses antennes de radiogoniométrie UHF large bande ou multibandes, néanmoins très peu d’entre elles permettent une couverture angulaire 3D. A notre connaissance, la première antenne de radiogoniométrie 3D fût étudiée dans les années 1960, par une équipe de l’université du Michigan. Composée de 17 capteurs positionnés sur une surface hémisphérique, sa taille et son nombre d’éléments en font un dispositif encombrant et complexe à utiliser. De récentes études ont proposé une autre approche basée sur la mesure multicomposante du champ électromagnétique, permettant de réduire la taille des antennes et le nombre d’éléments tout en conservant une couverture angulaire 3D. Cependant, à ce jours, seul des systèmes HF (3MHz-30MHz) ou bande étroite ont été abordés. Cette thèse porte donc sur l’étude et le développement d’une antenne vectorielle UHF multibande appliquée à la radiogoniométrie 3D pour des ondes transverses magnétiques. Tout d’abord, deux techniques de goniométrie adaptées à cette approche sont confrontées : une nouvelle technique basée sur la décomposition en harmonique sphérique du rayonnement de l’antenne qui permet de recomposer le champ électromagnétique reçu à partir d’échantillons mesurés et un algorithme bien connu, MUSIC. Une méthodologie de conception est proposée, en identifiant les critères physiques des antennes vectorielles qui influent sur leurs performances à savoir la précision d’estimation, la sensibilité, le nombre d’éléments et l’encombrement. Cette méthode est utilisée pour développer et réaliser une première antenne vectorielle monobande. La caractérisation de cette antenne réaliste permet d’écarter la première technique de traitement dont les performances sont trop sensibles aux perturbations de rayonnement. Une antenne vectorielle bibande compacte, d’un rayon de λ/4 et d’une hauteur de λ/5.5 à la fréquence la plus basse, composée de seulement six éléments rayonnants couvrant chacun les bandes de fréquences GSM [890MHz-960MHz] et [1710MHZ-1880MHz] est ensuite développée en se basant sur cette méthode de conception. Les capteurs électriques et magnétiques constituant l’antenne sont étudiés séparément puis assemblés selon une répartition spatiale planaire pour restreindre l’encombrement. Les structures rayonnantes sont communes pour les deux bandes de fréquences ce qui permet réduire le nombre d’éléments ainsi que les éventuelles perturbations de rayonnement. Après la caractérisation de l’antenne bibande au travers de simulations numériques, un prototype est réalisé et ses performances d’estimation sont mesurées en chambre anéchoïque afin de valider l’approche par simulation. La sensibilité obtenue est de -110dBW/m² (85μV/m) pour une précision de 5° RMS. Enfin l’étude est élargie au cas général d’antennes multibandes en illustrant le processus d’extension de la couverture fréquentielle par l’ajout d’une troisième bande, [400MHz-430MHz]. Six nouveaux éléments sont donc développés et intégrés aux capteurs GSM existants afin d’obtenir une antenne tribande d’un rayon de λ/3.2 et d’une hauteur de λ/12.5 à 400MHz. Malgré une légère augmentation de l’erreur d’estimation, causée par la présence de ces nouveaux éléments, la caractérisation de cette nouvelle antenne tribande montre de bonnes performances d’estimation avec une sensibilité de -105dBW/m² (155μV/m) pour une précision de 5° RMSNowadays, a lot of wideband or multiband direction finding antennas operating in the UHF band exist. Nevertheless, only few of them allow to estimate the direction of arrival in the full 3D space. At the author’s knowledge, the first 3D direction finding antenna was studied in the 1960s, at the University of Michigan. Composed of 17 sensors, located on a large hemispherical surface, this antenna is bulky and complex to use. Recently, some studies have proposed another approach based on the multicomponent measurement of the electromagnetic field that allows to decrease the antennas size and the number of radiating elements without reducing the 3D angular coverage. However, only HF (3-30MHz) or narrowband systems have been reported. The objective of this PhD is to study and to develop an UHF multiband vector sensor applied to the estimation of the direction of arrival of transverse magnetic waves in the full 3D space. Firstly, two signal processing techniques adapted to this approach are compared : a new technique based on the spherical harmonic decomposition of the antenna radiation which allows to recompose the received electromagnetic field from the measured samples and a well-known high resolution algorithm called MUSIC. A design methodology allowing to identify the physical criteria of vector sensors related to the antenna performances such as the estimation accuracy, the sensitivity, the number of elements and the antenna size is proposed. This method is used for developing and designing a first single-band vector sensor. The results obtained from numerical simulations allow to rule out the first signal processing technique which is too sensitive to the radiation perturbations. Then, a compact dual-band vector sensor operating in the GSM frequency band, [890MHz-960MHz] and [1710MHZ-1880MHz], is developed by using the same design methodology. The antenna size is λ/4 in radius and λ/5.5 in height at the lowest frequency. The electric and magnetic elements which compose the vector sensors are designed separately and then combined according to a planar spatial distribution to retain a compact antenna size. The same radiating structures are used for operating in the two frequency bands in order to reduce the number of elements and the eventual radiation perturbations. After the performances assessment through numerical simulations in each band, a prototype is manufactured and its estimation performances are measured for a validation purpose. The sensitivity is -110dBW.m−2 (85μV.m−1) for a 5◦ RMS angular accuracy. Finally, the study is extended to the general case of multiband antennas by adding a third band, [400MHz-430MHz]. New elements are developed and incorporated into the dual-band GSM sensors to obtain a tri-band vector sensor. The size of this new antenna is λ/3.2 in radius and λ/12.5 in height at 400MHz. Despite a slight increase of the angular errors in the estimation of the direction of arrival caused by the presence of the new antenna elements, the characterization of the tri-band sensor performances by simulation show a good accuracy with a sensitivity valued at -105dBW.m−2 (155μV.m−1) for a 5◦ RMS angular accuracy
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Broumas, Ioannis. "Design of Cellular and GNSS Antenna for IoT Edge Device." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-39239.
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Antennas are one of the most sensitive elements in any wireless communication equipment. Designing small-profile, multiband and wideband internal antennas with a simple structure has become a necessary challenge. In this thesis, two planar antennas are designed, simulated and implemented on an effort to cover the LTE-M1 and NB-IoT radio frequencies. The cellular antenna is designed to receive and transmit data over the eight-band LTE700/GSM/UMTS, and the GNSS antenna is designed to receive signal from the global positioning system and global navigation systems, GPS (USA) and GLONASS. The antennas are suitable for direct print on the system circuit board of a device. Related theory and research work are discussed and referenced, providing a strong configuration for future use. Recommendations and suggestions on future work are also discussed. The proposed antenna system is more than promising and with further adjustments and refinement can lead to a fully working solution.
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Ara?jo, Wellington Candeia de. "An?lise neurocomputacional de Antenas de microfita multibanda para sistemas de comunica??o sem fio." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15167.
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Previous issue date: 2007-08-10Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
This work presents a study of implementation procedures for multiband microstrip patch antennas characterization, using on wireless communication systems. An artificial neural network multilayer perceptron is used to locate the bands of operational frequencies of the antenna for different geometrics configurations. The antenna is projected, simulated and tested in laboratory. The results obtained are compared in order to validate the performance of archetypes that resulted in a good one agreement in metric terms. The neurocomputationals procedures developed can be extended to other electromagnetic structures of wireless communications systems
Esta disserta??o apresenta um estudo dos procedimentos de implementa??o para a caracteriza??o de antenas patch de microfita multibanda empregadas em sistemas de comunica??es sem fio. Uma rede neural artificial do tipo percepton multicamada ? empregada para localizar as bandas de freq??ncias operacionais da antena para diferentes configura??es geom?tricas. A antena ? projetada, simulada e testada em laborat?rio. Os resultados obtidos s?o comparados a fim de validar o desempenho dos prot?tipos que resultou numa boa concord?ncia em termos m?tricos. Os procedimentos neurocomputacionais desenvolvidos podem ser estendidos a outras estruturas eletromagn?ticas de sistemas de comunica??es sem fio
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DeJean, Gerald Reuben. "Design, Modeling, and Optimization of Compact Broadband and Multiband 3D System-On-Package (SOP) Antenna Architectures for Wireless Communications and Millimeter-Wave Applications." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14630.
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In recent years, the miniaturization of cell phones and computers has led to a requirement for antennas to be small and lightweight. Antennas, desired to operate in the WLAN frequency range, often possess physical sizes that are too large for integration with radio-frequency (RF) devices. When integrating antennas into three-dimensional (3D) system-on-package (SOP) transceivers, the maintenance of a compact size also provides isolation from other devices, hence, surface wave propagation or high dielectric constant materials such as low temperature cofired ceramics (LTCC) does not affect nearby components of the transceiver such as filters, baluns, and other embedded passives. Therefore, the application of design methods is necessary for realizing compact antennas in the wireless community that can be integrated to RF packages. Furthermore, it is essential that these compact antennas maintain acceptable performance characteristics, such as impedance bandwidth, low cross-polarization, and high efficiency. In addition, the analysis of circuit modeling techniques that could be used to obtain a better understanding of the physical phenomena of the antenna is quite necessary as modules become more and more complex. Based on these requirements, the focus of this research is to improve the design of compact antennas for wireless communications, wireless local area networks (WLAN), and millimeter-wave applications by using time-domain electromagnetic and circuit modeling techniques and optimizations. These compact antenna designs are applied to practical wireless communications systems such as global system of mobile communications (GSM), Bluetooth Industrial-Scientific-Medical (ISM) devices, IEEE802.11a WLAN, and Local Multipoint Distribution Systems (LMDS) applications. Parametric analyses are conducted to study critical parameters that may affect the antenna designs. Moreover, optimizations are performed to optimize the structures, and measured results are presented to validate design techniques.
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Ryšánek, Martin. "Vícepásmová magnetická anténa." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218593.
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The thesis deals with a parametric analysis of a magnetic multiband antenna and explains the principle of its operation. In the thesis, an optimization of the antenna by the particle swarm optimization is performed in order to meet impedance matching in prescribed frequency bands.
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D'assun??o, J?nior Adalido Gomes. "Uma nova proposta de antena planar multibanda para comunica??es m?veis." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18565.
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Previous issue date: 2007-02-22Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
The great interest observed in wireless communication systems has required the development of new configurations of microstrip antennas, because they are easily built and integrated to other microwave circuit components, which is suitable for the construction and development of planar antenna arrays and microwave integrated circuits. This work presents a new configuration of tapered microstrip antenna, which is obtained by impressing U-slots on the conducting patch combined with a transmission line matching circuit that uses an inset length. It is shown that the use of U-slots in the microstrip antenna conducting patch excites new resonating modes, that gives a multiband characteristic for the slotted microstrip antenna, that is suitable for applications in communication systems that operates several frequencies simultaneously. Up to this date, the works reported in the literature deals with the use of Uslotted microstrip rectangular antennas fed by a coaxial probe. The properties of a linear array of microstrip patch tapered antennas are also investigated. The main parameters of the U slotted tapered microstrip antennas are investigated for different sizes and locations of the slots impressed on the conducting patch. The analysis of the proposed antenna is performed by using the resonant cavity and equivalent transmission line methods, in combination with a parametric study, that is conducted by the use of the Ansoft Designer, a commercial computer aided microwave software well known by its accuracy and efficiency. The mentioned methods are used to evaluate the effect in the antennas parameters, like resonant frequency and return loss, produced by variations of the antenna structural parameters, accomplished separately or simultaneously. An experimental investigation is also developed, that consists of the design, construction and measurement of several U slotted microstrip antenna prototypes. Finally, theoretical and simulated results are presented that are in agreement with the measured ones. These results are related to the resonating modes identification and to the determination of the main characteristics of the investigated antennas, such as resonant frequency, return loss, and radiation pattern
A demanda por novos sistemas de comunica??es sem fio (wireless communication systems) tem requerido o desenvolvimento de novas configura??es de antenas de microfita, pois estas antenas apresentam uma grande facilidade de integra??o com outros componentes de circuito que facilitam a constru??o de arranjos planares e de circuitos integrados em freq??ncias de microondas. Neste trabalho ? analisada uma nova configura??o de antena de microfita afilada, na qual s?o introduzidas fendas em U (U-slots), no patch condutor, al?m de uma reentr?ncia (inset), atrav?s de uma se??o de linha de microfita, para fins de casamento da imped?ncia de entrada. A introdu??o de uma ou v?rias fendas no patch condutor da antena de microfita excita novos modos de resson?ncia, dando ? estrutura fendida uma caracter?stica de opera??o em multibanda, que possibilita a sua utiliza??o em sistemas com freq??ncias de opera??es distintas. Os trabalhos publicados com a impress?o de fendas em U dizem respeito ? utiliza??o de patches retangulares de microfita alimentados por cabo coaxial. Tamb?m ? investigada a associa??o de antenas afiladas na composi??o de arranjos lineares. S?o examinados e discutidos diversos aspectos relacionados com as dimens?es dessa fenda e o seu posicionamento no patch da antena considerada em termos do efeito produzido nas suas principais caracter?sticas de radia??o. A an?lise da antena proposta ? efetuada atrav?s dos m?todos da cavidade ressonante e da linha de transmiss?o modificados, em combina??o com um estudo param?trico, que ? realizado atrav?s do software comercial Ansoft Designer. Estes m?todos s?o empregados para avaliar as modifica??es produzidas nas caracter?sticas eletromagn?ticas, como a freq??ncia de resson?ncia e a perda de retorno, da antena em resposta ?s varia??es introduzidas em alguns dos seus par?metros estruturais. Al?m da investiga??o te?rica, ? inclu?da uma parte experimental que consistiu no projeto, constru??o e medi??o de v?rios prot?tipos configura??o de antena considerada. Finalmente, s?o apresentados resultados te?ricos (m?todos aproximados) e simulados (Ansoft Designer), que apresentam boa concord?ncia com os das medi??es efetuadas. Estes resultados consistem principalmente na identifica??o dos modos de resson?ncia e na determina??o das caracter?sticas principais das antenas consideradas, como a freq??ncia de resson?ncia, a perda de retorno e o diagrama de radia??o
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Abutarboush, Hattan F. "Fixed and reconfigurable multiband antennas." Thesis, Brunel University, 2011. http://bura.brunel.ac.uk/handle/2438/9037.
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With the current scenario of development of antennas in the wireless communication field, the need of compact multiband, multifunctional and cost effective antenna is on the rise. The objective of this thesis is to present fixed and reconfigurable techniques and methods for small and slim multiband antennas, which are applicable to serve modern small and slime wireless, mobile and cognitive radio applications. In the fixed designs, independent control of the operating frequencies is investigated to enhance the antennas capabilities and to give the designer an additional level of freedom to design the antenna for other bands easily without altering the shape or the size of the antenna. In addition, for mobile phone antenna, the effect of user’s hand and mobile phone housing are studied to be with minimum effect. Although fixed multiband antennas can widely be used in many different systems or devices, they lack flexibility to accommodate new services compared with reconfigurable antennas. A reconfigurable antenna can be considered as one of the key advances for future wireless communication transceivers. The advantage of using a reconfigurable antenna is to operate in multiband where the total antenna volume can be reused and therefore the overall size can be reduced. Moreover, the future of cell phones and other personal mobile devices require compact multiband antennas and smart antennas with reconfigurable features. Two different types of frequency reconfigurability are investigated in this thesis: switchable and tunable. In the switchable reconfigurability, PIN diodes have been used so the antenna’s operating frequencies can hop between different services whereas varactor diode with variable capacitance allow the antenna’s operating frequencies to be fine-tuned over the operating bands. With this in mind, firstly, a switchable compact and slim antenna with two patch elements is presented for cognitive radio applications where the antenna is capable of operating in wideband and narrow bands depending on the states of the switches. In addition to this, a switchable design is proposed to switch between single, dual and tri bands applications (using a single varactor diode to act as a switch at lower capacitance values) with some fine tuning capabilities for the first and third bands when the capacitance of the diode is further increased. Secondly, the earlier designed fixed antennas are modified to be reconfigurable with fine-tuning so that they can be used for more applications in both wireless and mobile applications with the ability to control the bands simultaneously or independently over a wide range. Both analytical and numerical methods are used to implement a realistic and functional design. Parametric analyses using simulation tools are performed to study critical parameters that may affect the designs. Finally, the simulated designs are fabricated, and measured results are presented that validate the design approaches.
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Abunjaileh, Alaa Ibrahim. "Multimode and multiband microstrip antennas." Thesis, University of Leeds, 2007. http://etheses.whiterose.ac.uk/759/.
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This thesis describes original work on the broadband and multiband matching of microstrip patch antennas. Microstrip patch antennas suffer from many constraints on their performance. One major restriction is their narrow impedance bandwidth. An effective method to resolve this is adding more resonators to the antenna structure to achieve multi-resonance and hence wider bandwidth. Structures such as circular, square and triangular patch antennas may support two orthogonal resonant modes or polarisations. This allows excitation of an additional resonance beside the fundamental. With the correct coupling between the resonant modes, the impedance bandwidth can be significantly increased. The equivalent circuit of such structures is similar to those used in microwave filter design. Using techniques normally employed in filter synthesis, the equivalent circuits can be generated, and aid in finding the couplings and dimensions of the specified antenna requirement. The bandwidth of circular microstrip patch antennas is significantly increased by exciting two modes on a single circular microstrip antenna, and four modes using two stacked circular microstrip patches. In this work, the designs are also extended into multimode antennas achieving multi-frequency operation.
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Bulgaroni, Renan Guimarães. "Projeto de antenas planares de baixo custo para sistemas Multibanda." reponame:Repositório Institucional da UFABC, 2016.
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Orientador: Prof. Dr. Ivan Roberto Santana CasellaDissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2016.
Este trabalho visa o desenvolvimento de antenas planares multibanda de baixo custo para aplicações em sistemas de comunicações sem fio. As antenas propostas, baseadas nas topologias Quasi-Yagi e Vivaldi para sistemas SISO (Single Input Single Output) e Meandered Loop para sistemas MIMO (Multiple Input Multiple Output), foram otimizadas para operar nas faixas de frequência das redes LTE (Long Term Evolution), WiFi (Wireless Fidelity) e WIMAX (Worldwide Interoperability For Microwave Access). Após os estudos preliminares de simulação e otimização para a definição final das topologias propostas, foram montados alguns protótipos para a realização de testes de medida e comprovação experimental das funcionalidades das antenas.
This work is aimed at developing low-cost multiband planar antennas for applications in wireless communications systems. Antennas proposals based on Quasi-Yagi topologies and Vivaldi for SISO systems (Single Input Single Output) and meandered Loop for MIMO (Multiple Input Multiple Output) were optimized to operate in the frequency bands of the LTE (Long Term Evolution), WiFi (Wireless Fidelity) and WIMAX (Worldwide Interoperability For Microwave Access). After the preliminary studies simulation and optimization for the final definition of the proposed topologies, some prototypes were assembled to perform measurement tests and experimental verification of the functionalities of antennas.
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Huitema, Laure. "Conception d’antennes miniatures à base de matériaux innovants pour systèmes de communications mobiles." Limoges, 2011. https://aurore.unilim.fr/theses/nxfile/default/a25b0fa1-3acc-4afb-ad61-8ca9e1c81d3f/blobholder:0/2011LIMO4031.pdf.
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Face à la volonté d’intégrer une quantité toujours plus importante de nouveaux services au sein des terminaux mobiles de nouvelle génération et afin de répondre à leurs contraintes d’encombrement, de nouveaux concepts d’antennes intelligentes font l’objet de nombreuses recherches. Le principal objectif est d’offrir de nouveaux services avec une qualité de réception optimale aux abonnés tout en s’inscrivant dans la tendance du marché. L’antenne devra donc être miniature et capable de s’adapter à son environnement, c'est-à-dire à des conditions changeantes en ajustant sa fréquence de travail, sa polarisation ou son diagramme de rayonnement. Deux axes sont explorés dans le cadre de cette thèse. Dans un premier temps, il est nécessaire de s’attaquer au verrou de l’encombrement des antennes et de la coexistence de divers services en explorant les potentialités offertes par le développement de matériaux originaux pour la miniaturisation des antennes. A partir des résultats obtenus, il devient alors possible d’envisager des concepts d’antennes miniatures dont l’objectif est d’introduire des fonctions d’agilité pour adapter les performances de l’antenne à son environnement et à son contexte d’utilisation. Ce mémoire propose de répondre à ces deux objectifs en présentant le développement, la conception et la réalisation de quatre architectures d’antennes miniatures et reconfigurables à base de matériaux innovantsGiven the desire to integrate a large number of new services in last generation of mobile handheld devices and in order to drastically decrease their dimensions, new concepts of smart antennas are being considered. The main objective is to offer new services in a trendy mobile handheld with an optimal quality and an improved link budget. The antenna has to be small and in order to improve the reliability of wireless links, the antenna structure must have a frequency tunability, a reconfigurable polarization or radiation pattern. In order to satisfy these objectives, this manuscript focuses on two axes. At first, it is necessary to unlock the constraints on the miniaturization of such antennas to multiple services by studying the potentialities and effectiveness of original materials dedicated to the compliance and optimization of the antenna performances within its environment. Thanks to this study, it is then possible to investigate new concepts of reconfigurable antennas to optimize their performances within their environment. This manuscript is proposing answers to these challenges by detailing the development, the conception and the manufacturing of four different miniature and reconfigurable antenna designs using new kind of materials
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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.
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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
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Ramanandraibe, Marosoa Esthelladi. "Miniaturisation des antennes de station de base RFID dans la bande UHF et leur fonctionnement en multibande, par l'utilisation de métamatériaux." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S125.
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Les dimensions d’une antenne sont inversement proportionnelles à leurs fréquences de fonctionnement. De plus, la miniaturisation d’une antenne entraîne la dégradation de ses performances électriques et de rayonnement. Par conséquent, il est important pour le concepteur de trouver un bon compromis entre le taux de miniaturisation et les performances souhaitées. L’objet de cette thèse est de proposer une antenne miniature possédant les meilleures caractéristiques possibles dans la bande UHF de la RFID (860MHz – 960MHz), facile à réaliser et à moindre coût d’industrialisation. Les travaux de cette thèse ont montré qu’un couplage magnétique d’une cellule de métamatériaux avec une demi-boucle permet d’obtenir des structures antennaires intéressantes de par leurs dimensions de l’ordre de λ0/10, leur efficacité et leur fonctionnement en multibande. Différentes techniques sont appliquées pour améliorer les performances des antennes développées à savoir le gain, la directivité et la polarisation circulaire et/ou elliptiqueAntenna dimensions are inversely proportional to their operating frequencies. Besides, the antenna miniaturization degrades its electrical and radiation performances. Therefore it is important for the antenna designer to find a good compromise between the miniaturization rate and the desired performances. The purpose of this thesis is to obtain a miniature antenna which has good characteristics in the UHF band of RFID (860MHz - 960MHz), easy to implement and with low industrialization cost. The works described in this thesis showed that a magnetic coupling of a metamaterial cell with a half loop provides interesting antennas in terms of dimensions of about λ0/10, efficiency and multiband behavior. Different techniques are applied to improve the performances of realized antennas as gain, directivity and circular and/or elliptical polarization
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Ben, Abdillah Sidi Mohamed. "Application des fractals à la conception d'antennes compactes et multibandes." Toulouse 3, 2005. http://www.theses.fr/2005TOU30156.
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Considérant la révolution des communications sans fil ces dernières années, les équipements des nouveaux systèmes de communication deviennent de plus en plus petits. Par exemple, les téléphones mobiles fonctionnent à plusieurs fréquences (GSM, GPS, UMTS,. . . ) et tiennent en un unique terminal ultra portable. Ce constat de plus en plus délicat la tâche des concepteurs d'antennes. Dans ces travaux, nous proposons une approche simple de la conception d'antennes bi-bandes très compactes. Des stubs sont placés le long d'un dipôle afin d'obtenir le comportement fréquentiel désiré. La géométrie fractale permet quant à elle de réduire la taille de l'antenne. Les antennes présentées sont très compactes et ont une couverture hémisphérique. Les relations entre les descripteurs fractales et les performances des antennes sont discutées. Des exemples d'antennes fractales bi-bandes sont également réalisées et mésuréesRegarding the wireless revolution in the last years, equipments in new communications systems are getting smaller and smaller. Moreover these systems incorporate different services. For example, mobile phones operate at several communications systems (GPS, GSM, UMTS. . . ) in single and small handheld devices. These facts give more and more challenges to antenna designers. A simple approach for designing dual-band and ultra-compact antennas is proposed in this work. Stubs are placed along simple dipole for achieving dual-band feature while fractal geometry is used for minimizing the size of the antenna. The design methodology is presented. The proposed antennas are highly compact and cover a quasi-hemispherical area. Relationship between descriptors of fractal profiles and performances of the proposed antennas are discussed. Examples of these dual band compact antennas are presented and measured for validation
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FERREIRA, Hélio Renato Oeiras. "Projeto de antenas multibandas integradas para terminais 4G." Universidade Federal do Pará, 2014. http://repositorio.ufpa.br/jspui/handle/2011/6705.
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O presente trabalho apresenta um projeto e análise de uma antena monopolo planar multibanda operante nas frequências de 2000 MHz, 2500 MHz e 3500 MHz para aplicação em dispositivos móveis 3G e 4G. Dentre essas faixas estão contidos os espectros 3G (1895- 2165 MHz), 4G (2500-2690 MHz) e 4G (3400-3600 MHz) utilizadas pelo LTE e WIMAX 3,5. Para o desenvolvimento desse estudo foi tomado como referência uma antena dual-band de Hua- Ming Chen projetada para operar em sistemas ISM 1800 MHz, redes Wireless e Bluetooth 2400 MHz. O projeto proposto neste trabalho é uma modificação na estrutura da antena dual-band adaptada para tripla ressonância simultânea em frequências utilizadas em redes móveis 4G. Para alcançar o objetivo proposto utilizou-se para simulação o software CST® MICROWAVE STUDIO baseado no método Integração Finita no Domínio, as simulações foram feitas no domínio do tempo. Após obtenção satisfatória dos resultados simulados, um protótipo da antena foi confeccionado para medição e teste, os resultados apresentados são coerentes aos obtidos na simulação, o que valida o método proposto.
This paper presents a design and analysis of a planar monopole antenna operating in multiband frequencies of 2000 MHz, 2500 MHz and 3500 MHz for use in 3G and 4G mobile devices. Among these bands are contained 3G (1895-2165 MHz), 4G (2500-2690 MHz) and 4G (3400-3600 MHz) spectra used by LTE and WIMAX 3.5. For the development of this study was taken as reference Hua-Ming Chen’s dual-band antenna designed to operate at ISM systems (1800 MHz), wireless networks and Bluetooth (2400 MHz). The project proposed in this work is a modification in the structure of the dual-band antenna adapted for simultaneous triple resonance frequencies used in 4G mobile networks. To achieve the proposed objective was used to simulate the CST® MICROWAVE STUDIO software based on the Finite Integration method in Domain; the simulations were done in the time domain. After obtaining satisfactory simulated results, a prototype antenna was built to test and measurement; the presented results are consistent with those obtained in the simulation, which validates the proposed method.
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KUO, Chun-Yi, and 郭俊逸. "Design of Multiband Planar Antenna." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/94193761606288531922.
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YUEH, WANG CHUNG, and 王忠嶽. "Multiband Antenna Simulation and Design." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/34012930120670476862.
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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.
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Chen, Wen-Wang, and 陳文旺. "Design of Multiband Operation Antenna." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/58373468536045029929.
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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 ).
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Siao, Sin-long, and 蕭新朧. "Miniaturized GPS chip antenna and multiband monopole antenna." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/09486805850704632333.
Full textAbstract:
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.
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FAN, CHIH-WEI, and 范智偉. "Design of Multiband Coplanar slot antenna." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/63944947429000173611.
Full textAbstract:
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
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Chao, Chun-heng, and 趙君恒. "Study of multiband slot antenna designs." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/2gzp58.
Full textAbstract:
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.
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TIAN, CHANG-FU, and 田章甫. "Design of Multiband Planar Dipole Antenna." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/9tuy5f.
Full textAbstract:
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
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Hsieh, Yuan-pu, and 謝沅圃. "Multiband CPW-fed slot antenna design." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/10018352714300872868.
Full textAbstract:
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.
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Zeng, Jian-Hong, and 曾建弘. "Design of Multiband Planar MIMO Antenna." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/23593305021202076714.
Full textAbstract:
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.
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Chen, Zhi-Ying, and 陳智穎. "Design of Printed Multiband LTE Antenna." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/u79ves.
Full textAbstract:
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.
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YU, JIA-YI, and 余家一. "Designs on Multiband Antenna for LTE Applications." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/02510455459107705088.
Full textAbstract:
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.
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Pan, Po-Yu, and 潘柏宇. "Study of Multiband Monopole Antenna for LTE." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/3jrg8n.
Full textAbstract:
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.
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Bakytbekov, Azamat. "Fully Printed 3D Cube Cantor Fractal Rectenna for Ambient RF Energy Harvesting Application." Thesis, 2017. http://hdl.handle.net/10754/626269.
Full textAbstract:
Internet of Things (IoT) is a new emerging paradigm which requires billions of wirelessly connected devices that communicate with each other in a complex radio-frequency (RF) environment. Considering the huge number of devices, recharging batteries or replacing them becomes impractical in real life. Therefore, harvesting ambient RF energy for powering IoT devices can be a practical solution to achieve self-charging operation.
The antenna for the RF energy harvesting application must work on multiple frequency bands (multiband or wideband) to capture as much power as possible from ambient; it should be compact and small in size so that it can be integrated with IoT devices; and it should be low cost, considering the huge number of devices.
This thesis presents a fully printed 3D cube Cantor fractal RF energy harvesting unit, which meets the above-mentioned criteria. The multiband Cantor fractal antenna has been designed and implemented on a package of rectifying circuits using additive manufacturing (combination of 3D inkjet printing of plastic substrate and 2D metallic screen printing of silver paste) for the first time for RF energy harvesting application. The antenna, which is in a Cantor fractal shape, is folded on five faces of a 3D cube where the bottom face accommodates rectifying circuit with matching network. The rectenna (rectifying antenna) harvests RF power from GSM900, GSM1800, and 3G at 2100 MHz frequency. Indoor and outdoor field tests of the RF energy harvester have been conducted in the IMPACT lab and the King Abdullah University of Science and Technology (KAUST) campus territory, and 252.4 mV of maximum output voltage is harvested.
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Lee, Meng-Che, and 李孟哲. "A Novel Method for Multiband Filtering Antenna Design." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/n72zq3.
Full textAbstract:
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.
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Chen, Weichuan, and 陳韋銓. "Design of Compound Multiband Antenna for Portable Devices." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/65785114206860943501.
Full textAbstract:
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.
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Wang, Tai-Ming, and 汪泰名. "The Study in Multiband Elliptical-truncated Microstrip Antenna." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/72692904210775834297.
Full textAbstract:
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).
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YANG, YI-YUNG, and 楊義勇. "Multiband antenna designs for applications in smart watches." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/58834346466725631023.
Full textAbstract:
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.
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Chan, Chao-Kai, and 詹兆凱. "A Coupling Slot Multiband Antenna for Mobile Phones." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/65325308419270386965.
Full textAbstract:
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.
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Wang, Yi-Shiang, and 王奕翔. "Planar Multiband Antenna Designs for Tablet Computer Application." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/58632872871716047666.
Full textAbstract:
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.
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Gu, Jiun-Peng, and 辜駿鵬. "An LTE smart mobile antenna with multiband operation." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/36566617569139439907.
Full textAbstract:
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.
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Wan, Yu-Chang, and 萬育章. "LTE Multiband Antenna Design for Wireless Network Applications." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/7nrv6y.
Full textAbstract:
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.
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謝維庭. "Multiband Antenna for WWAN/LTE Mobile Phone Applications." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/fzfmb3.
Full textAbstract:
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
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Ming-Hung, Hsu, and 徐銘鴻. "A Printed Slot Antenna for Multiband Mobile Applications." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/844n2w.
Full textAbstract:
碩士國立臺北科技大學
電資碩士在職專班研究所
103
This paper presents an innovative antenna structure which is support most of the GSM/WCDMA/UMTS band. And it can be implemented to the current mobile devices for the multi-band LTE (Long Term Evolution) technology systems. This design features devices to cover LTE(704 MHz~746MHz)、LTE (824 MHz ~ 894 MHz), LTE (880 MHz ~ 960 MHz) and high-band LTE (1710 MHz ~ 2170 MHz) by this single structure to cover the majority of today&;#39;s LTE operating bands. The characteristics of this simple structure can be implemented directly to the printed circuit board, and achieved the extensive application, while keeping the advantage of saving costs. This multi-band antenna employs two meandered coupling structure between fed and slot structure to excite three resonance modes, enabling this antenna to achieve the multiple communication bands. The presented bending structure is able to add a slot to achieve the desired high frequency range in LTE (1710 MHz ~ 2170 MHz) bands. The verification will be executed through the simulation and actual production measurement. The operational frequency of this antenna is: 310 MHz in the low band (700 MHz -1010 MHz) and 650MHz in the high band (1550 MHz -2200 MHz). The area of the antenna radiator is 22.5 × 70 mm2.
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XIE, JIA-YING, and 謝佳瑩. "Design and Investigation of the Multiband Wearable Antenna." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/95uq3f.
Full textAbstract:
碩士銘傳大學
電腦與通訊工程學系碩士班
106
The great demanding of wearable electronic devices recently has drawn more attention on new wearable antenna. Many kinds of antenna which are suitable to the medical detection, smart watch communication as well as smart eyeglasses etc. were studied for different applications. The smart watch antenna is one of the booming items for the new-type antenna. In the design, it needs to take care of not only it size but also to meet the good-looking profile. Under these limitation, the wearable antenna for the smart watch becomes of great challenge, especially on multiband antenna. In this study, we develop the new antenna based on 30 x 30 mm square area by using microstrip lines. In order to fit the profile of smart watch, the antenna is designed to reduce the size and fit the profile of 30 x 30 mm square area with 2.5 mm surrounding zone. A new-type of dual band wearable antenna is designed in this study. It successfully meets the GPS and 2.4 GHz frequency. Our study not only shows the details of the antenna design, but also presents the measured results including the throughput and the performance of the new multiband wearable watch.
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Chiu, Tzu-Ling. "Multiband DRA for automotive applications with beam steering." Thesis, 2017. http://www.theses.fr/2017LIMO0112/document.
Full textAbstract:
Les antennes à pointage électronique présentent des avantages significatifs dans les systèmes de communication sans fil. Malgré cela elles ne sont toujours pas implantées dans l'industrie automobile. En effet, l'espace limité et le toit en grande partie métallique freinent l’utilisation de ces aériens dans ce contexte contraint. De nombreux défis restent à relever pour concevoir un système efficace, peu encombrant, faible coût et permettant de rayonner sur 360°. L’objectif de cette thèse est donc la mise au point d’une antenne à balayage électronique pour application automobile fonctionnant dans la bande LTE. Un système de «type MIMO » est proposé. Une antenne à résonateur diélectrique efficace, multi-bandes et efficace est conçue selon une procédure de développement spécifique. Un déphaseur accordable est également mis au point et réalisé. Il utilise des commutateurs et un condensateur variable. Un déphasage de 360 degrés est obtenu, le dispositif est commandé électriquement. L’antenne et le déphaseur sont ensuite associés dans un système complet fonctionnant dans la bande LTE. Celui-ci utilise deux antennes identiques, une seule étant alimentée. Ce système complet est mesuré seul et sur le véhicule. Les résultats obtenus sont prometteurs et permettent d’envisager, moyennant quelques améliorations, une exploitation industrielle. Les études menées pour aboutir à ce dispositif sont détaillées dans le manuscritEven though beam steering technology has significant advantages in wireless communication systems, it is still not implemented in the automotive industry. Indeed, the limited space and the large metal sheet on the rooftop are the challenges for such system. This thesis is focused on the design of the LTE beam steering antenna based on a MIMO system for an automotive environment. An appropriate multiband, efficient and compact Dielectric Resonator Antenna is conceived using a specific development procedure. Also, a tunable phase shifter is designed and realized with switches and a variable capacitor. It has 360 degrees phase shift and can be electrically controlled. The proposed DRA and phase shifter are integrated in a global antenna system for automotive application in the LTE band. We finally propose a MIMO system with an active beam steering radiation pattern. It is very compact and can be implemented on the vehicle rooftop. Using the proposed phase shifter, a beam steering antenna is obtained with a global coverage close to 360� for the antenna alone or on the vehicle. Measurements are made in the using context of the antenna. Finally, the developed system is, with some improvement, powerful for powerful enough for "commercial" automotive applications. The studies carried out to develop this antenna are detailed in this manuscript
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黃健羽. "Design of Multiband Antenna for Smart Handheld Mobile Device." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/89078711825480430621.
Full text
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Yeh, Po-Way, and 葉柏瑋. "Printed Monopole Slot Antenna for Multiband Mobile Handset Device." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/65751633664701030869.
Full textAbstract:
碩士國立臺灣大學
電信工程學研究所
100
Due to the development of wireless communication, everyone needs cell phones. People demand that a cell phone should get more functions, so mobile device should cover more bands to satisfy people’s desire. Because of the foregoing reason, antenna should have the ability to work with multiband functions, such as GSM800、GSM900、DCS(Digital Communication System)、PCS(Personal Communication Services)、UMTS(Universal Mobile Telecommunication System )、Wi-Fi、WiMax (Worldwide Interoperability for Microwave Access)、WLAN(Wireless Local Area Networks)、bluetooth. On the other hand, the size of the antenna has to become smaller, and the antenna design needs to find the balance between antenna size and performance. This thesis focuses on multi-band antenna design by using multiple monopole slot antennas. Feed it with a microstrip line. Use multiple resonance path to generate the reguired multiband function.
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HSU, CHENG-WEI, and 徐晟崴. "Design of Multiband Coplanar Dipole Antenna with Meander Line." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6mdu7y.
Full textAbstract:
碩士明新科技大學
電機工程系碩士班
108
In this thesis, FR4 substrate is used to fabricate the planar dipole antenna. IE3D software is used to simulate the single meander line coplanar dipole antenna with 2.4/2.45/3.5/5.0/5.2/5.8 GHz application frequency band and multiple meandering line coplanar dipole antenna with 1.8/2.4/2.45/3.5/5.0/5.2 GHz application frequency band. The single meander line coplanar dipole (SML) antenna with notch paramters L1/W2 and meander line length parameter W6 are changed to observe the effect of these parameters on antenna characteristics and the suitable parameters are chosen to fabricate the single meander line coplanar dipole antenna. The peak gain and S11 of the fabricated antenna are 2.460dBi/-17.63dB, 1.972dBi/-16.46dB, 1.360dBi/-11.09dB, 2.697dBi/-18.17dB, 3.258dBi/-16.95dB and 2.033dBi/-15.39dB, at 2.4 GHz, 2.45 GHz, 3.5 GHz, 5.0 GHz, 5.2 GHz and 5.8 GHz, respectively. The operating frequency bands of the fabricated SML antenna from 1.07 GHz to 1.10 GHz, 2.08 GHz to 2.87 GHz, 3.50 GHz to 3.79 GHz and 4.53 GHz to 6.00 GHz are obtained. This antenna can be used in RFID 2.45/5.8 GHz, WLAN 2.4/5.2/5.8 GHz and 5G 3.5 GHz/5.0 GHz frequency bands. The rectangle notch is change to triangle notch for SML antenna. The better triangle notch structure is chosen and menander line length parameter L2 of the multiple meander line coplanar dipole (MML) antenna is changed to observe the effect of L2 parameter on antenna characteristics and the suitable parameter is chosen to fabricate MML antenna. The peak gain and S11 of the fabricated MML antenna are 1.742dBi/-10.13dB, 0.997dBi/-19.38dB, 0.497dBi/-13.62dB, 2.062dBi/-12.01dB, 0.173dBi/-11.62dB and 0.331dBi/-10.389dB, at 1.8 GHz, 2.4 GHz, 2.45 GHz, 3.5 GHz, 5.0 GHz and 5.2 GHz, respectively. The operating frequeny bands of the fabricated MML antenna from 0.99 GHz to 1.09 GHz, 1.80 GHz to 2.08 GHz, 2.36 GHz to 2.53 GHz and 2.88 GHz to 5.28 GHz are obtained. This antenna can be used in GSM 1.8 GHz, RFID 2.45 GHz, WLAN 2.4/5.2/5.8 GHz and 5G 3.5 GHz/5.0 GHz frequency bands. In this study, the fabricated SML and MML antennas can be used for various operating frequency band demand.
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CHIANG, CHIH-YANG, and 蔣志暘. "Design of Small-Size Multiband Antenna for Laptop Computer Applications." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/m59agy.
Full textAbstract:
碩士逢甲大學
電機工程學系
105
This thesis focuses on the design of multiband uniplanar antennas for portable devices. Here, two different uniplanar antennas are proposed, and they have used 50 Ω mini coaxial cables as their feed mechanism. The two proposed antennas can be inserted into any mobile devices with limited or narrow spaces. This thesis first proposed a miniaturized WLAN antenna design. The structure of this proposed WLAN antenna 1 is comprised of a driven strip, and a folded shorted strip, so that two resonance modes can be excited and able to cover entire WLAN 2.4/5.2/5.8 GHz operating bands. The overall size of the proposed antenna 1 is only 13 × 6 × 0.8 mm3. In order to achieve further miniaturization, as compared with proposed antenna 1, another miniaturized WLAN antenna design is also proposed, and it is comprised a driven strip and a folded strip, so that two resonance modes can be excited and able to cover entire WLAN 2.4/5.2/5.8 GHz operating bands. The overall size of this proposed antenna 2 is only 11 × 6.5 × 0.8 mm3. Finally, from the parametric analysis of the system ground plane size, even when enlarging or reducing the ground size, the lower operating bandwidth, higher operating bandwidth, and impedance matching of two proposed antennas will remain unaffected. Therefore, it can be concluded that the two proposed antennas have exhibited reduce ground plane effects. Furthermore the ground size of proposed antennas 1 and 2 can be reduced to 70 × 80 mm2 and 40 × 50 mm2, respectively. Notably, the main advantage of this work is that one can touch the ground plane of these two proposed antennas directly, and it will not affect the lower or higher operating bandwidths. Therefore, the two proposed antennas presented in this thesis can be fitted easily into any portable device without affecting the antenna’s performances.