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1
Morsy, Mohamed Mostafa. "DESIGN AND IMPLEMENTATION OF MICROSTRIP MONOPOLE AND DIELECTRIC RESONATOR ANTENNAS FOR ULTRA WIDEBAND APPLICATIONS." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/dissertations/169.
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Ultra wide-band (UWB) technology is considered one of the very promising wireless technologies in the new millennium. This increases the demand on designing UWB antennas that meet the requirements of different UWB systems. In this dissertation, different UWB antennas are proposed such as an antenna that covers almost the entire UWB bandwidth, 3.5-11 GHz, as defined by the federal communication commission (FCC). This antenna has a size of 50×40×1.5mm3. Miniaturized worldwide UWB antennas are also introduced. Miniaturized worldwide UWB antennas that have compact sizes of (30×20×1.5) mm3, and (15×15×1.5) mm3 are also investigated. The designed worldwide UWB antennas cover the UWB spectrums defined by the electronic communication committee (ECC), 6-8.5 GHz, and the common worldwide UWB spectrum, 7.4-9 GHz. A system consisting of two identical antennas (transmitter and receiver) is built in the Antennas and Propagation Lab at Southern Illinois University Carbondale (SIUC) to test the coupling properties between every two identical antennas. The performance of that system is analyzed under different ii conditions to guarantee that the transmitted signal will be correctly recovered at the receiver end. The designed UWB antennas can be used in many short range applications such as wireless USB. Wireless USB is used in PCs, printers, scanners, laptops, MP3 players, hard disks and flash drives. A new technique is introduced to widen the impedance bandwidth of dielectric resonator antennas (DRAs). DRA features compactness, low losses, and wideband antennas. Different compact UWB DRAs are investigated in this dissertation. The designed DRAs cover a wide range of frequency bands such as, 6.17-24GHz, 4.23-13.51GHz, and 4.5-13.6GHz. The designed DRAs have compact sizes of 1×1×1.5cm3, 0.9×0.9×1.32cm3, 0.6×0.6×1cm3, and 0.6×0.6×0.9cm3; and cover the following frequency bands 4.22-13.51GHz, 4.5-13.6GHz, 6.1-23.75GHz, and 6.68-26.7GHz; respectively. The proposed DRAs may be used for applications in the X, Ku and K bands such as military radars and unmanned airborne vehicles (UAV).
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Alam, Muhammad Faiz, and Muhammad Faiz Alam. "Dielectric Resonator Antennas (DRA) for satellite and body area network applications." Phd thesis, Université Paris-Est, 2012. http://tel.archives-ouvertes.fr/tel-00795292.
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Technologies such as direct broad cast satellite system (DBSS), Geosynchronous Earth Orbit (GEO) and Low Earth Orbit (LEO) satellite communications , global positioning system (GPS), high accuracy airborne navigation system and a large variety of radar systems demand for high level of antenna performance. Similar is the requirement for upcoming land based wireless systems such as cellular and indoor communication systems that is needed some more specific and additional features added to the antenna to compensate for the deficiencies encountered in system's performance. Though metallic antennas are capable enough to fulfil all the operational requirements, however at very high frequencies and under hostile temperature conditions they are constrained to face certain limitations. To avoid these constraints the performance of Dielectric Resonator Antennas (DRAs) is evaluated and their new applications are proposed. In the thesis, two types of antenna applications are sought :-First is for tracking and satellite applications that needs a larger aperture coverage in elevation plane. This coverage is realized with a good CP purity by proposing two ports dual linearly polarized DRA working at X-band. The DRA is excited by two orthogonal H-shaped aperture slots yielding two orthogonal polarizations in the broadside direction. A common impedance bandwidth of 5.9% and input port isolation of -35 dB are obtained. The broadside radiation patterns are found to be highly symmetric and stable with cross polarization levels -15dB or better over the entire matching frequency band. The maximum measured gain is found to be 2.5dBi at 8.4 GHz.- The 2nd type of antenna is a dual pattern diversity antenna to be used in the Body Area Network (BAN) context. This antenna combines a slot loop and DRA yielding broadside and end-fire radiation patterns respectively. Based upon the feeding techniques, the DG antenna is further divided into two categories one with planar feeds and the other with non-planar feeds (slot loop excited by planar CPW but DRA excited by vertical monopole) .Both types are successfully designed and measured upon body when configured into different propagation scenarios. The non-planar feeds antenna allows wider common impedance bandwidths than the planar feeds (4.95% vs 1.5%).In both cases, a maximum value of DG=9.5dB was achieved when diversity performance tests were carried out in rich fading environments. This value is close to the one (10 dB) theoretically reached in a pure Rayleigh environment and was obtained with efficiencies of 70% and 85% for the slot loop and the DRA respectively. Therefore, we conclude that these antennas could be used on the shoulders or the chest of professional clothes (firemen, policemen, soldier) where full planar integration is not a key issue but where the communication must be efficient in harsh environments and for various gestures, positions and scenarios
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Alam, Muhammad Faiz. "Dielectric Resonator Antennas (DRA) for satellite and body area network applications." Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1057/document.
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Dans cette thèse, on vise deux types d'applications de l’antenne à résonateur diélectrique (DRA): 1) La réalisation d’un élément rayonnant pour un réseau phasé embarqué sur un véhicule terrestre ou un avion. Cet élément de base requiert une couverture en élévation supérieure à celle des éléments imprimés pour permettre une poursuite typique comprise entre ±70°. La couverture dans un cône large est assurée avec une bonne pureté de polarisation circulaire en alimentant l’antenne à travers deux ouvertures à fente en H orthogonales parfaitement découplées en bande X. 2) La deuxième structure est destinée à la diversité d’antennes dans le contexte des réseaux corporels embarqués ou Body Area Network (BAN). L’antenne à diversité combine une antenne fente en boucle avec un DRA ce qui permet dans un espace compact de réaliser des diagrammes de type “broadside” et “endfire” respectivement. Les alimentations considérées sont de 2 types; Soit purement planaire (microruban et coplanaire) soit mixte en combinant une alimentation coaxiale et une alimentation coplanaire. Caractéristiques principales des antennes à résonateur diélectrique (DRA): Pour répondre aux attentes des utilisateurs en termes de débit, les systèmes de communication sans fils se tournent vers des fréquences de plus en plus élevées. La conséquence de cette montée en fréquence est notamment l’augmentation des pertes au niveau des éléments conducteurs et donc une diminution de l’efficacité globale des systèmes de communication. Dans ces circonstances, les DRA offre de meilleurs résultats par rapport à d'autres familles d'antennes à base d’éléments métalliques. De plus, les DRA offrent des pertes diélectriques négligeables, elles sont peu sensibles aux variations de température et s’intègrent facilement sur des technologies de fabrication planairesTechnologies such as direct broad cast satellite system (DBSS), Geosynchronous Earth Orbit (GEO) and Low Earth Orbit (LEO) satellite communications , global positioning system (GPS), high accuracy airborne navigation system and a large variety of radar systems demand for high level of antenna performance. Similar is the requirement for upcoming land based wireless systems such as cellular and indoor communication systems that is needed some more specific and additional features added to the antenna to compensate for the deficiencies encountered in system's performance. Though metallic antennas are capable enough to fulfil all the operational requirements, however at very high frequencies and under hostile temperature conditions they are constrained to face certain limitations. To avoid these constraints the performance of Dielectric Resonator Antennas (DRAs) is evaluated and their new applications are proposed. In the thesis, two types of antenna applications are sought :-First is for tracking and satellite applications that needs a larger aperture coverage in elevation plane. This coverage is realized with a good CP purity by proposing two ports dual linearly polarized DRA working at X-band. The DRA is excited by two orthogonal H-shaped aperture slots yielding two orthogonal polarizations in the broadside direction. A common impedance bandwidth of 5.9% and input port isolation of -35 dB are obtained. The broadside radiation patterns are found to be highly symmetric and stable with cross polarization levels -15dB or better over the entire matching frequency band. The maximum measured gain is found to be 2.5dBi at 8.4 GHz.- The 2nd type of antenna is a dual pattern diversity antenna to be used in the Body Area Network (BAN) context. This antenna combines a slot loop and DRA yielding broadside and end-fire radiation patterns respectively. Based upon the feeding techniques, the DG antenna is further divided into two categories one with planar feeds and the other with non-planar feeds (slot loop excited by planar CPW but DRA excited by vertical monopole) .Both types are successfully designed and measured upon body when configured into different propagation scenarios. The non-planar feeds antenna allows wider common impedance bandwidths than the planar feeds (4.95% vs 1.5%).In both cases, a maximum value of DG=9.5dB was achieved when diversity performance tests were carried out in rich fading environments. This value is close to the one (10 dB) theoretically reached in a pure Rayleigh environment and was obtained with efficiencies of 70% and 85% for the slot loop and the DRA respectively. Therefore, we conclude that these antennas could be used on the shoulders or the chest of professional clothes (firemen, policemen, soldier) where full planar integration is not a key issue but where the communication must be efficient in harsh environments and for various gestures, positions and scenarios
4
Elmegri, Fauzi O. M. "Model and design of small compact dielectric resonator and printed antennas for wireless communications applications : model and simulation of dialectric resonator (DR) and printed antennas for wireless applications : investigations of dual band and wideband responses including antenna radiation performance and antenna design optimization using parametric studies." Thesis, University of Bradford, 2015. http://hdl.handle.net/10454/14742.
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Dielectric resonator antenna (DRA) technologies are applicable to a wide variety of mobile wireless communication systems. The principal energy loss mechanism for this type of antenna is the dielectric loss, and then using modern ceramic materials, this may be very low. These antennas are typically of small size, with a high radiation efficiency, often above 95%; they deliver wide bandwidths, and possess a high power handling capability. The principal objectives of this thesis are to investigate and design DRA for low profile personal and nomadic communications applications for a wide variety of spectrum requirements: including DCS, PCS, UMTS, WLAN, UWB applications. X-band and part of Ku band applications are also considered. General and specific techniques for bandwidth expansion, diversity performance and balanced operation have been investigated through detailed simulation models, and physical prototyping. The first major design to be realized is a new broadband DRA operating from 1.15GHz to 6GHz, which has the potential to cover most of the existing mobile service bands. This antenna design employs a printed crescent shaped monopole, and a defected cylindrical DRA. The broad impedance bandwidth of this antenna is achieved by loading the crescent shaped radiator of the monopole with a ceramic material with a permittivity of 81. The antenna volume is 57.0 37.5 5.8 mm3, which in conjunction with the general performance parameters makes this antenna a potential candidate for mobile handset applications. The next class of antenna to be discussed is a novel offset slot-fed broadband DRA assembly. The optimised structure consists of two asymmetrically located cylindrical DRA, with a rectangular slot feed mechanism. Initially, designed for the frequency range from 9GHz to 12GHz, it was found that further spectral improvements were possible, leading to coverage from 8.5GHz to 17GHz. Finally, a new low cost dual-segmented S-slot coupled dielectric resonator antenna design is proposed for wideband applications in the X-band region, covering 7.66GHz to 11.2GHz bandwidth. The effective antenna volume is 30.0 x 25.0 x 0.8 mm3. The DR segments may be located on the same side, or on opposite sides, of the substrate. The end of these configurations results in an improved diversity performance.
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Elmegri, Fauzi. "Model and design of small compact dielectric resonator and printed antennas for wireless communications applications. Model and simulation of dialectric resonator (DR) and printed antennas for wireless applications; investigations of dual band and wideband responses including antenna radiation performance and antenna design optimization using parametric studies." Thesis, University of Bradford, 2015. http://hdl.handle.net/10454/14742.
Full textAbstract:
Dielectric resonator antenna (DRA) technologies are applicable to a wide variety of
mobile wireless communication systems. The principal energy loss mechanism for this
type of antenna is the dielectric loss, and then using modern ceramic materials, this
may be very low. These antennas are typically of small size, with a high radiation
efficiency, often above 95%; they deliver wide bandwidths, and possess a high power
handling capability.
The principal objectives of this thesis are to investigate and design DRA for low profile
personal and nomadic communications applications for a wide variety of spectrum
requirements: including DCS, PCS, UMTS, WLAN, UWB applications. X-band and part
of Ku band applications are also considered. General and specific techniques for
bandwidth expansion, diversity performance and balanced operation have been
investigated through detailed simulation models, and physical prototyping.
The first major design to be realized is a new broadband DRA operating from 1.15GHz
to 6GHz, which has the potential to cover most of the existing mobile service bands.
This antenna design employs a printed crescent shaped monopole, and a defected
cylindrical DRA. The broad impedance bandwidth of this antenna is achieved by
loading the crescent shaped radiator of the monopole with a ceramic material with a
permittivity of 81. The antenna volume is 57.0 37.5 5.8 mm3, which in conjunction
with the general performance parameters makes this antenna a potential candidate for
mobile handset applications.
The next class of antenna to be discussed is a novel offset slot-fed broadband DRA
assembly. The optimised structure consists of two asymmetrically located cylindrical
DRA, with a rectangular slot feed mechanism. Initially, designed for the frequency
range from 9GHz to 12GHz, it was found that further spectral improvements were
possible, leading to coverage from 8.5GHz to 17GHz.
Finally, a new low cost dual-segmented S-slot coupled dielectric resonator antenna
design is proposed for wideband applications in the X-band region, covering 7.66GHz
to 11.2GHz bandwidth. The effective antenna volume is 30.0 x 25.0 x 0.8 mm3. The DR
segments may be located on the same side, or on opposite sides, of the substrate. The
end of these configurations results in an improved diversity performance.General Secretariat of Education and Scientific Research Libya
6
Slavíček, Radek. "Návrh periodických struktur pro zvýšení směrovosti dielektrických rezonátorových antén." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-377333.
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The thesis deals with linearly polarized dielectric rectangular resonator antenna (DRA) operating in the basic mode TEy11 and higher order mode TEy131 at f0 = 10GHz surrounded by an electromagnetic band gap structure (EBG). The dielectric resonator antennas, the EBG structure were designed and a method of integration of both components was developed. The simulated results show a significant improvement of the radiation pattern in the E-plane radiation pattern (narrower main beam, lower level of side lobes, higher directivity) in comparison to a conventional DRA. This was verified by the TEy11 measurement.
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Martins, Jo?mia Leilane Gomes de Medeiros. "An?lise de antenas utilizando substrato cer?mico, zpt, produzido por s?ntese auto propagante para aplica??es em sistemas de micro-ondas." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15230.
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Ceramic substrates have been investigated by researchers around the world and has achieved a high interest in the scientific community, because they had high dielectric constants and excellent performance in the structures employed. Such ceramics result in miniaturized structures with dimensions well reduced and high radiation efficiency. In this work, we have used a new ceramic material called lead zinc titanate in the form of Zn0,8Pb0,2TiO3, capable of being used as a dielectric substrate in the construction of various structures of antennas. The method used in constructing the ceramic combustion synthesis was Self- Sustained High Temperature (SHS - "Self-Propagating High-Temperature Synthesis") which is defined as a process that uses highly exothermic reactions to produce various materials. Once initiated the reaction area in the reaction mixture, the heat generated is sufficient to become self-sustaining combustion in the form of a wave that propagates converting the reaction mixture into the product of interest. Were analyzed aspects of the formation of the composite Zn0,8Pb0,2TiO3 by SHS powders and characterized. The analysis consisted of determining the parameters of the reaction for the formation of the composite, as the ignition temperature and reaction mechanisms. The production of composite Zn0,8Pb0,2TiO3 by SHS performed in the laboratory, was the result of a total control of combustion temperature and after obtaining the powder began the development of ceramics. The product was obtained in the form of regular, alternating layers of porous ceramics and was obtained by uniaxial pressing. 10 The product was characterized by analysis of dilatometry, X-ray diffraction analysis and scanning electron microscopy. One of the contributions typically defined in this work is the development of a new dielectric material, nevertheless presented previously in the literature. Therefore, the structures of the antennas presented in this work consisted of new dielectric ceramics based Zn0,8Pb0,2TiO3 usually used as dielectric substrate. The materials produced were characterized in the microwave range. These are dielectrics with high relative permittivity and low loss tangent. The Ansoft HFSS, commercial program employee, using the finite element method, and was used for analysis of antennas studied in this work
Substratos cer?micos t?m sido investigados por pesquisadores de todo o mundo e tem despertado um grande interesse na comunidade cient?fica, pelo fato de apresentarem altas constantes diel?tricas e um excelente desempenho nas estruturas empregadas. Tais cer?micas resultam em estruturas miniaturizadas, com dimens?es bem reduzidas e de alta efici?ncia de radia??o. Neste trabalho, utilizou-se um novo material cer?mico, chamado de titanato de zinco chumbo, na forma de Zn0,8Pb0,2TiO3, capaz de ser utilizado como substrato diel?trico na constru??o de diversas estruturas de antenas. O m?todo utilizado na constru??o da cer?mica foi a S?ntese por Combust?o Auto-Sustentada a Alta Temperatura (SHS Self-Propagating High-Temperature Synthesis ) que ? definido como um processo que utiliza rea??es altamente exot?rmicas para produzir os mais diversos materiais. Uma vez iniciada a rea??o numa ?rea da mistura reagente, o calor gerado ? suficiente para tornar a combust?o auto-sustent?vel, na forma de uma onda que se propaga convertendo a mistura reagente no produto de interesse. Foram analisados os aspectos da forma??o do comp?sito Zn0,8Pb0,2TiO3 por SHS e os p?s obtidos, foram caracterizados. A an?lise consistiu na determina??o dos par?metros da rea??o para a forma??o do comp?sito, como a temperatura de igni??o e os mecanismos de rea??o. A produ??o do comp?sito Zn0,8Pb0,2TiO3 por SHS, realizada em laborat?rio, foi resultado de um controle total da temperatura de combust?o e ap?s a obten??o do p? 8 iniciou-se o desenvolvimento das cer?micas. O produto foi obtido na forma de camadas regulares e altern?ncia de porosidades e as cer?micas foram obtidas por prensagem uniaxial. O produto foi caracterizado atrav?s de an?lises de dilatometria, difra??o de raios-X e an?lise de microscopia de varredura eletr?nica. Uma das contribui??es principais deste trabalho foi o desenvolvimento de um novo material diel?trico, n?o obstante apresentado anteriormente na literatura. Portanto, as estruturas das antenas apresentadas neste trabalho foram constitu?das por novas cer?micas diel?tricas ? base de Zn0,8Pb0,2TiO3, geralmente utilizado como substrato diel?trico. Os materiais desenvolvidos foram caracterizados na faixa de micro-ondas. S?o substratos diel?tricos de alta permissividade relativa e baixa tangente de perda. O software comercial empregado, Ansoft HFSS, baseado no m?todo dos elementos finitos, foi utilizado na an?lise das antenas estudadas neste trabalho
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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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Henry, B. "Investigation of rectangular dielectric resonator antenna elements and arrays." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0001/MQ44845.pdf.
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Zhang, Yizhe. "Dielectric resonator antenna arrays with hard horn for wideband spatial power combining /." Full text available from ProQuest UM Digital Dissertations, 2007. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1414125761&SrchMode=1&sid=5&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1220635872&clientId=22256.
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Eshrah, Islam A. "Waveguide and metaguide excitation of dielectric resonator antenna arrays using slots and probes /." Full text available from ProQuest UM Digital Dissertations, 2005. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1267222711&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1184857149&clientId=22256.
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Liu, Chia-Wei. "Development of Automatic Design Optimization Method for Ultrawide Bandwidth (UWB) Multi-Layer Dielectric Rod Antenna." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306512723.
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Zbořil, Jan. "Širokopásmové dielektrické antény." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219865.
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The diploma project deals with the numerical modeling, implementation and measurement of dielectric dipoles excited by a coaxial probe. Attention was turned to shape optimization of dipoles from the viewpoint of ultra wideband parameters in the band group 6. (“Bandgroup 6“). Two antennas exhibiting the best parameters were fabricated. Results of measurements were compared with simulation results. Simulations and measurements were in agreement. For the simulations, we use program CST Microwave Studio.
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Dutta, Chaudhury Nandan. "An investigation on the possibility for bandwidth improvement of dielectric antennas via modification of their geometry." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-285571.
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The dielectric antenna is an interesting alternative to a metallic antenna. This is mainlydue to its low manufacturing cost and the possibility to fabricate complex antennageometry with the aid of additive manufacturing (AM). Sophisticated AM technologyprovides new degrees of freedom in shaping the outer and inner geometry of antennas.This feature can be utilized to optimize various properties of antenna, such as itsbandwidth, radiation pattern etc, while maintaining a compact geometry.This master thesis investigates the possibility of improving the bandwidth of acompact dielectric antenna by modifying its geometry. Specifically, dielectricresonator antennas (DRAs) have been considered here. In this connection, twoembedded cylindrical DRAs operating within 8 GHz-17 GHz frequency band havebeen designed and simulated using Ansys HFSS. For the first design (Design-1), abandwidth (corresponding to reflection coefficient ≤ -10dB) of approximately 63%has been obtained and the second design (Design-2) has a bandwidth (correspondingto reflection coefficient ≤ -10dB) of about 57%. However, in terms of radiationcharacteristics, the performance of Design-2 has been found to be superior comparedto Design-1, mainly due to its symmetrical geometry. Furthermore, the two designshave been compared to an existing compact rectangular embedded DRA. It has beenfound that both Design-1 and Design-2 have comparatively wider bandwidth. Withrespect to the radiation characteristics, the performance of the reference antenna andDesign-2 are similar. While, the radiation performance of the reference antenna isfound to be better than Design-1.Dielektriska antenner är ett intressant alternativ till metalliska diton. Detta beror delspå lägre tillverkningskostnader men också, tack vare additiva tillverkningsmetoder,på grund av möjligheten att använda komplexa geometrier. De senaste årens framsteginom additiv tillverkning har öppnat upp nya möjligheter vid designen av den externaoch den inre geometrin hos dielektriska antenner. Detta kan utnyttjas till att optimeraolika aspekter hos antennen, exempelvis bandbredd och strålningsmönster, utan attpåverka de yttre måtten.Denna avhandling studerar möjligheten att förbättra bandbredden hos dielektriskaresonansantenner (DRA) genom att modifiera deras inre. Två cylindriska DRA:er,verksamma inom 8-17 GHz, har designats och simulerats i Ansys HFSS. Bandbredderom 63 % för Design-1, samt 57 % för Design-2, erhölls. Trots den första designensstörre bandbredd uppvisar Design-2 bättre strålningsegenskaper, främst avseendeantennens strålningsmönster. De simulerade antennerna har också visat sig hastörre bandbredd jämfört med en redan existerande kompakt, inbäddad DRA. Sett tillstrålningsegenskaper är prestandan hos Design-2 jämförbar med referensantennen,medan design ett uppvisar sämre prestanda.
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Mehmood, Arshad [Verfasser], Rolf [Akademischer Betreuer] Jakoby, and Klaus [Akademischer Betreuer] Solbach. "Dielectric Resonator Antenna and Array Concepts based on Glass, Ceramics and Glass-ceramics / Arshad Mehmood ; Rolf Jakoby, Klaus Solbach." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2018. http://d-nb.info/1161846964/34.
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Bernabeu, Jiménez Tomás. "Contribution to the physical interpretation of characteristic mode resonances. Application to dielectric resonator antennas." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/86177.
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The Theory of Characteristic Modes is being adopted by many research groups around the world in the last decade. This topic and their use in different metallic antenna design is growing very fast. However, most of the applications has been only concentrated on conducting surfaces without any physical knowledge about its limitations and its physical interpretation. As far as dielectric bodies are concerned, there have not been so many published articles. The reason is that there are different integro-differential formulations and the interpretation of their solutions is not as obvious as in conducting bodies. Here, a theoretical interpretation considering loss-less conducting and dielectric bodies is presented.
The conclusions drawn in this thesis will allow us to better understand the solutions of the Theory of Characteristic Modes and their limitations. This is important for antenna engineering. In addition, this analysis will allow to develop a novel method for the design of antennas based on dielectric resonators, DRA. This method is called Substructure based-PMCHWT method, and is based on the implementation of the Schur complements of the method of moments matrix operator. This study permits to optimize the radiation bandwidth in the same analysis process for both, the dielectric and the feed, e.g. slot. Moreover, it allows to understand how the slot behaves in the presence of the dielectric resonator and vice versa. This method can also be used to design DRA using low permittivities. This is important in the design of DRA because the feed perturbs the system and produces a shift in the resonances of the characteristic modes. So, therefore, by considering the feed system in the characteristic modes analysis a more realistic results than a conventional analysis is obtained. On the other hand, the resonances of the characteristic modes at low permittivities are displaced from what are the natural resonances of the dielectric resonator and also the corresponding S11 resonance. Thus, designing with this new method it can draw new conclusions about the design of DRA using the Theory of Characteristic Modes.En la última década, la teoría de los modos característicos está siendo utilizada por muchos grupos de investigación en todo el mundo. Este tema y su uso en diferentes diseños de antenas metálicas está creciendo muy rápido. Sin embargo, la mayoría de las aplicaciones se han concentrado únicamente en antenas metálicas sin ningún conocimiento físico acerca de sus limitaciones y su interpretación física. En lo que se refiere a cuerpos dieléctricos, no han habido tantos artículos publicados como en metales. La razón es que existen diferentes formulaciones integro-diferenciales y la interpretación de sus soluciones no es tan obvia como en cuerpos metálicos. En esta tesis se presenta una interpretación física de las soluciones de la Teoría de Modos Característicos al considerar cuerpos metálicos y dieléctricos sin pérdidas. Las conclusiones de esta tesis nos permitirán comprender mejor las soluciones de la Teoría de Modos Característicos y sus limitaciones. Esto es importante en ingeniería de antenas. Además, este análisis permitirá desarrollar un nuevo método para el diseño de antenas basadas en resonadores dieléctricos, DRA. Este método está basado en la formulación PMCHWT y la función de Green multicapa utilizada en el método de los momentos (MoM). A este nuevo método se le ha denominado "Substructure Characteristic Mode method", y está basado en la implementación de los complementos Schur sobre las submatrices del operador del MoM. Este estudio permite optimizar el ancho de banda de radiación de un DRA en el mismo proceso de análisis tanto para el dieléctrico como para la alimentación, como por ejemplo una ranura. Además, este método permite comprender como se comporta la ranura en presencia del resonador dieléctrico y viceversa. Este método también puede usarse para diseñar DRA usando permitividades bajas. Esto es importante en el diseño de DRA porque la alimentación perturba el sistema y produce un cambio en las resonancias de los modos característicos. Por lo tanto, al considerar la alimentación en el análisis de modos característicos se obtienen resultados más realistas comparándolos con los obtenidos mediante un análisis convencional. Así, diseñando con el "Substructure Characteristic Mode method" se pueden extraer nuevas conclusiones sobre el diseño de DRA mediante la Teoría de Modos Característicos.
En l'última dècada, la teoria dels modes característics està sent utilitzada per molts grups d'investigació en tot el món. Este tema i el seu ús en diferents dissenys d'antenes metàl·liques està creixent molt ràpid. No obstant això, la majoria de les aplicacions s'han concentrat únicament en superfícies conductores sense cap coneixement físic sobre les seues limitacions i la seua interpretació física. Pel que fa a cossos dielèctrics, no hi ha hagut tants articles publicats com en metalls. La raó és que hi ha diferents formulacions integro- diferencials i la interpretació de les seues solucions no és tan òbvia com en cossos conductors. En esta tesi es presenta una interpretació teòrica considerant cossos conductors i dielèctrics sense pèrdues. Les conclusions d'esta tesi ens permetran comprendre millor les solucions de la Teoria de Modes Característics i les seues limitacions. Açò és important en enginyeria d'antenes. Açò és important en enginyeria d'antenes. A més, esta anàlisi permetrà desenrotllar un nou mètode per al disseny d'antenes basades en ressonadors dielèctrics, DRA. Este mètode està basat en la formulació PMCHWT i la funció de Green multicapa utilitzada en el mètode dels moments (MoM) . A este nou mètode se li ha denominat "Substructure Characteristic Mode method", i està basat en la implementació dels complements Schur sobre les submatrius de l'operador del MoM. Este estudi permet optimitzar l'amplada de banda de radiació d'un DRA en el mateix procés d'anàlisi tant per al dielèctric com per a l'alimentació, com per exemple una ranura. A més, este mètode permet comprendre com es comporta la ranura en presència del ressonador dielèctric i viceversa. Este mètode també pot usar-se per a dissenyar DRA usant baixes permitivitats. Açò és important en el disseny de DRA perquè l'alimentació pertorba el sistema i produïx un canvi en les ressonàncies dels modes característics. Per tant, al considerar l'alimentació en l'anàlisi de modes característics s'obtenen resultats més realistes comparant-los amb els obtinguts per mitjà d'una anàlisi convencional. Així, dissenyant amb el "Substructure Characteristic Mode method" es poden extraure noves conclusions sobre el disseny de DRA per mitjà de la Teoria de Modes Característics.
Bernabeu Jiménez, T. (2017). Contribution to the physical interpretation of characteristic mode resonances. Application to dielectric resonator antennas [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86177
TESIS
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Davids, Vernon Pete. "Design and Implementation of an Integrated Solar Panel Antenna for Small Satellites." Thesis, Cape Peninsula University of Technology, 2019. http://hdl.handle.net/20.500.11838/3044.
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Thesis (PhD (Electrical Engineering))--Cape Peninsula University of Technology, 2019This dissertation presents a concept for a compact, low-profile, integrated solar panel antenna for use on small satellites in low Earth orbit. To date, the integrated solar panel antenna design approach has primarily been, patch (transparent or non-transparent) and slot radiators. The design approach presented here is proposed as an alternative to existing designs. A prototype, comprising of an optically transparent rectangular dielectric resonator was constructed and can be mounted on top of a solar panel of a Cube Satellite. The ceramic glass, LASF35 is characterised by its excellent transmittance and was used to realise an antenna which does not compete with solar panels for surface area. Currently, no closed-form solution for the resonant frequency and Q-factor of a rectangular dielectric resonator antenna exists and as a first-order solution the dielectric waveguide model was used to derive the geometrical dimensions of the dielectric resonator antenna. The result obtained with the dielectric waveguide model is compared with several numerical methods such as the method of moments, finite integration technique, radar cross-section technique, characteristic mode analysis and finally with measurements. This verification approach was taken to give insight into the resonant modes and modal behaviour of the antenna. The interaction between antenna and a triple-junction gallium arsenide solar cell is presented demonstrating a loss in solar efficiency of 15.3%. A single rectangular dielectric resonator antenna mounted on a ground plane demonstrated a gain of 4.2 dBi and 5.7 dBi with and without the solar cell respectively. A dielectric resonator antenna array with a back-to-back Yagi-Uda topology is proposed, designed and evaluated. The main beam of this array can be steered can steer its beam ensuring a constant flux density at a satellite ground station. This isoflux gain profile is formed by the envelope of the steered beams which are controlled using a single digital phase shifter. The array achieved a beam-steering limit of ±66° with a measured maximum gain of 11.4 dBi. The outcome of this research is to realise a single component with dual functionality satisfying the cost, size and weight requirements of small satellites by optimally utilising the surface area of the solar panels.
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Costa, Rodrigo Carvalho Souza. "Estudo experimental e numÃrico de uma antena ressoadora dielÃtrica baseada em CaTi1Âx(Nb2=3Li1=3)xO3ÂÂ (CNLTO) e CaTi1Âx(Nb1=2Ln1=2)xO3 (Ln = Bi (CNBTO) e Fe (CNFTO)) para aplicaÃÃes em bluetooth." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2043.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoCoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
O progresso da indÃstria de telecomunicaÃÃes depende da fabricaÃÃo em larga escala de circuitos de baixo custo, alto desempenho elÃtrico, confiabilidade e passividade de miniaturizaÃÃo. Estas caracterÃsticas sÃo necessÃrias para garantir que os sinais transmitidos sejam confinados a uma freqÃÃncia bem definida, evitando assim sinais que possam interferir no desempenho satisfatÃrio de sistemas de telecomunicaÃÃes. As cerÃmicas dielÃtricas fornecem vantagens significantes em termos de compactaÃÃo, peso, estabilidade tÃrmica e custos de produÃÃo em dispositivos de micro-ondas, alÃm de possuir uma grande facilidade de integraÃÃo com outros circuitos integrados de microondas. Este trabalho consiste no desenvolvimento e caracterizaÃÃo de um novo tipo de material cerÃmico para ser utilizado como uma antena miniatura para aplicaÃÃes em Bluetooth (2.4 GHz). O trabalho està dividido em trÃs etapas. A primeira consiste em desenvolver um novo material que possua constante dielÃtrica (25 < Âr < 50), um alto fator de qualidade (Q > 5000) e um coeficiente de temperatura da freqÃÃncia de ressonÃncia (Âf ) prÃximo de zero. A segunda consiste em caracterizar o material desenvolvido atravÃs de DifraÃÃo de Raios-X e Espectroscopias Raman, Infra-vermelho e DielÃtrica. A Ãltima etapa consiste em fabricar e simular a antena feita com o material desenvolvido, comparando o desempenho teÃrico com o prÃtico.
The progress of telecommunication industry is highly dependent of the fabrication of low cost, quality factor and smaller size of the individual components for commercial applications. This kind of characteristics are necessary to warranty that the signal have well suited frequency, avoiding the noise interference signals, that could affect the performance of the telecommunication systems. Dielectric ceramics have significant advantages of light weight, low cost, small size, low profile, high radiation eficiency, low production cost and ease of integration with other active or passive microwave integrated circuit. This work will provide a new ceramic material that could be used in a miniature antenna for Bluetooth applications. This work is divided in three stages. The first one is develop a new material with a good dielectric permittivity (25 < Âr < 50), high quality factor (Q > 5000) and low temperature coeficient of resonant frequency (Âf ). The second one characterize the developed material by XDR, Raman, Infrared and dielectric spectroscopy in microwave region. The last one is build and simulate the antenna made with the developed dielectric material.
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Kubín, Petr. "Dielektrická rezonátorová anténa na bázi vlnovodu integrovaného do substrátu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220271.
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The Master’s thesis deals with the design of the dielectric resonator antenna array based on the substrate integrated waveguide. The work describes various feed methods of the dielectric resonator antenna and the technique of the design of the antenna. The antenna array was designed in the simulative program ANSYS HFSS at the frequency 10 GHz, subsequently fabricated and measured. The antenna array has the bandwidth of 570 MHz for S11 better than –10 dB and the gain of 12.1 dBi.
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Bezerra, Josà Wagner de Oliveira. "Estudo numÃrico/experimental de antena ressoadora dielÃtrica circularmente polarizada com alimentaÃÃo por sonda Ãnica." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8101.
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nÃo hÃA expansÃo das redes de telecomunicaÃÃes sem fio e o fenÃmeno da convergÃncia digital trazem a inerente necessidade da pesquisa de novos componentes que assegurem a sustentabilidade e a evoluÃÃo dos sistemas. Novos tipos de antenas, menores e mais eficientes, sÃo exigidas à medida que novos dispositivos vÃo surgindo. Neste contexto, as antenas ressoadoras dielÃtricas, construÃdas com novos materiais, aparecem como excelente opÃÃo para substituir as antenas metÃlicas tradicionais. Este trabalho apresenta uma proposta de antena ressoadora dielÃtrica circularmente polarizada, operando na frequÃncia central de 2,25 GHz, na qual um esquema de alimentaÃÃo por sonda Ãnica à empregado para excitar dois modos ressonantes em um dielÃtrico em forma de quarto de cilindro. Este leiaute permite a ativaÃÃo de modos de baixa ordem, com distribuiÃÃo ortogonal dos campos eletromagnÃticos, ressoando em frequÃncias prÃximas com uma diferenÃa de fase de 90Â. SÃo introduzidos conceitos da teoria eletromagnÃtica envolvendo cavidades ressonantes e caracterÃsticas dos materiais cerÃmicos que compÃem o dielÃtrico. AlÃm disso, os processos de modelagem por computador e de construÃÃo de um protÃtipo sÃo explicados. Os resultados sÃo discutidos comparativamente entre o modelo computacional e as medidas experimentais executadas em laboratÃrio. O estudo demonstra uma boa concordÃncia entre os resultados simulados e os experimentais e evidencia a viabilidade da antena para aplicaÃÃes que necessitem de polarizaÃÃo circular na regiÃo do espectro de frequÃncias prÃximas a 2,25 GHz.
The expansion of wireless telecommunications networks and the phenomenon of digital convergence bring the inherent need for research of new components to ensure the sustainability and evolution of the systems. New types of antenna, smaller and more efficient, are required as new devices emerge. In this context, the dielectric resonator antennas, built with new materials, appear as an excellent option to replace the conventional metallic antennas. This work presents a proposal for a circularly polarized dielectric resonator antenna to operate at the center frequency of 2.25 GHz in which a single probe feeding scheme is used to excite two resonant modes in a quarter-cylinder-shaped dielectric. This layout allows the activation of low-order modes with orthogonal distribution of electromagnetic fields, resonating at near frequencies with a 90Â phase difference. The concepts of electromagnetic theory related to resonant cavities and the characteristics of dielectric ceramic materials are introduced. Furthermore, the processes of computer modeling and constructing of a prototype are explained. The results are discussed by comparison between the computational model and experimental measurements performed in the laboratory. The study shows a good agreement between the simulated and experimental results and demonstrates the feasibility of the antenna for applications requiring circular polarization for operating at the region of the frequency spectrum close to 2.25 GHz.
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Mrnka, Michal. "Perforovaná dielektrika a dielektrické rezonátorové antény s vyššími módy." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-320299.
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Práce se zabývá buzením vyšších módů v kvádrových a válcových dielektrických rezonátorových anténách pro účely zvýšení zisku. Pomocí numerických simulací jsou studovány vlastnosti a limity anténních prvků. Je zkoumáná vzájemní vazba mezi dielektrickými rezonátorovými anténami pracujícími s vyššími vidy a na základě výsledků je možno usuzovat o vhodnosti těchto prvků k popužití v anténních řadách. V práci je popsán analytický model efektivní permitivity perforovaných dielektrik, který respektuje anizotropní povahu tohoto materiálu. Model je založen na Maxwell Garnettové aproximácií nehomogenních materiálů. Dále jsou studovány povrchové vlny na perforovaných substrátech a je ověřena použitelnost teoretického modelu i v tomto případě. Nakonec jsou studovány dielektrické rezonátorové antény vytvořené pomocí perforací v dielektrickém substrátu a je demonstrováno zhoršení určitých vlastností takových antén.
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Matsumuro, Takayuki. "Advanced Beam Forming by Synthesizing Spherical Waves for Progressive Microwave Power Transmission." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225602.
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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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Elmegri, Fauzi, Chan H. See, Raed A. Abd-Alhameed, and Peter S. Excell. "Dielectric resonator antenna design for lower-UWB wireless applications." 2013. http://hdl.handle.net/10454/9649.
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NoA small dielectric resonator antenna has been designed for ultra wideband (UWB) communication system applications. The antenna element is a rectangular low permittivity ceramic block, with a dielectric constant of 9.4, and the modified T-shaped feed network includes a 50 ohm microstrip line to achieve strong coupling, and some bandwidth enhancement. The antenna performance is simulated and measured over a frequency band extending from 3100 MHz to 5500 MHz; the impedance bandwidth over this interval is 55.8% with VSWR <; 2, making the antenna suitable for UWB applications.
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Zebiri, Chemseddine, Mohamed Lashab, D. Sayad, Issa T. Elfergani, Khalil H. Sayidmarie, F. Benabdelaziz, Raed A. Abd-Alhameed, Jonathan Rodriguez, and James M. Noras. "Offset Aperture-Coupled Double-Cylinder Dielectric Resonator Antenna with Extended Wideband." 2017. http://hdl.handle.net/10454/13087.
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YesA compact dielectric resonator antenna for ultra-wideband vehicular communication applications is proposed. Two cylindrical dielectric resonators are asymmetrically located with respect to the center of an offset rectangular coupling aperture, through which they are fed. Optimizing the design parameters results in an impedance bandwidth of 21%, covering the range from 5.9 to 7.32 GHz in the lower-band and a 53% relative bandwidth from 8.72 to 15 GHz in the upper-band. The maximum achieved gain is 12 dBi. Design details of the proposed antenna and the results of both simulations and experiment are presented and discussed.
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Majeed, Asmaa H., Abdulkareem S. Abdullah, Raed A. Abd-Alhameed, and Khalil H. Sayidmarie. "MIMO Antenna Array Using Cylindrical Dielectric Resonator for Wide Band Communications Applications." 2014. http://hdl.handle.net/10454/8304.
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YesThe present work investigates the operation performance of 2-element configuration multiple input Multiple Output (MIMO) antennas system using Cylindrical Dielectric Resonator (CDR). The MIMO antenna arrays achieve 22.2% impedance bandwidth at S11 ≤ -10 covering the bandwidth from 10GHz to 12.5GHz that meets the essential requirements of wide band communications applications. The first array gives a maximum isolation of 27dB at an element spacing of 22mm, whereas the second array presents a maximum isolation of 42.55dB at element spacing of 12.25mm.
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Majeed, Asmaa H., Abdulkareem S. Abdullah, Fauzi Elmegri, Khalil H. Sayidmarie, Raed A. Abd-Alhameed, and James M. Noras. "Aperture-Coupled Asymmetric Dielectric Resonators Antenna for Wideband Applications." 2014. http://hdl.handle.net/10454/8422.
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yesA compact dielectric resonator antenna (DRA) for wideband applications is proposed. Two cylindrical dielectric resonators which are asymmetrically located with respect to the center of a rectangular coupling aperture are fed through this aperture. By optimizing the design parameters, an impedance bandwidth of about 29%, covering the frequency range from 9.62 GHz to 12.9 GHz, and a gain of 8 dBi are obtained. Design details of the proposed antenna and the results of both simulation and experiment are presented and discussed.
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Majeed, Asmaa H., Abdulkareem S. Abdullah, Khalil H. Sayidmarie, Raed A. Abd-Alhameed, and Fauzi Elmegri. "Compact Dielectric Resonator Antenna with Band-Notched Characteristics for Ultra-Wideband Applications." 2015. http://hdl.handle.net/10454/7884.
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yesIn this paper, a compact dielectric resonator antenna (DRA) with band-notched characteristics for ultra-wideband applications is presented. A comprehensive parametric study was carried out using CST Microwave Studio Suite TM 2011 to analyze and optimize the characteristics of the proposed antenna. Three shapes for the coupling slot were investigated. Simulation results show that the proposed DRA had a −10 dB impedance bandwidth of 23% from 9.97 GHz to 12.558 GHz, and a maximum gain of 7.23 dBi. The antenna had a notched band centered at 10.57 GHz, which increased the reflection coefficient by 23.5 dB, and reduced the gain by 6.12 dB. The optimized designs were verified by experimental tests on fabricated samples.
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Majeed, Asmaa H., Abdulkareem S. Abdullah, Fauzi Elmegri, Khalil H. Sayidmarie, Raed A. Abd-Alhameed, and James M. Noras. "Dual Segment S-Shaped Aperture-Coupled Cylindrical Dielectric Resonator Antenna for X-Band Applications." 2015. http://hdl.handle.net/10454/7885.
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yesA new low-cost dual-segmented dielectric resonator (DR) antenna design is proposed for wideband applications in the X-band region. Two DRs coupled to an S-shaped slot introduce interesting features. The antenna performance was characterized in terms of the reflection coefficient, gain, and radiation pattern, and detailed simulation studies indicate excellent antenna performance from 7.66 GHz to 11.2 GHz (37.5% fractional bandwidth) with a maximum gain of 6.0 dBi at 10.6 GHz while the fabricated prototype has a matched bandwidth from 7.8 GHz to 11.85 GHz (41% fractional bandwidth) and maximum gain of 6dBi. The antenna is compact, size 1 x 0.83 x 0.327 time the wavelength at 10 GHz. The two DR segments may be located on the same side or on opposite sides of the substrate, giving respectively improved gain or more uniform field patterns. Experimental testing of the prototype performance showed reasonable agreement with the predicted performance.
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"Exciting the Low Permittivity Dielectric Resonator Antenna Using Tall Microstrip Line Feeding Structure and Applications." Thesis, 2013. http://hdl.handle.net/10388/ETD-2013-08-1143.
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The development of wireless communications increases the challenges on antenna performance to improve the capability of the whole system. New fabrication technologies are emerging that not only can improve the performance of components but also provide more options for materials and geometries. One of the advanced technologies, referred to as deep X-ray lithography (XRL), can improve the performance of RF components while providing interesting opportunities for fabrication.
Since this fabrication technology enables the objects of high aspect ratio (tall) structure with high accuracy, it offers RF/microwave components some unique advantages, such as higher coupling energy and compacted size. The research presented in that thesis investigates the properties of deep XRL fabricated tall microstrip transmission line and describes some important features such as characteristic impedance, attenuation, and electromagnetic field distribution. Furthermore, since most of traditional feeding structure cannot supply enough coupling energy to excite the low permittivity DRA element (εr≤10), three novel feeding schemes composed by tall microstrip line on exciting dielectric resonator antennas (DRA) with low permittivity are proposed and analyzed in this research. Both simulation and experimental measured results exhibit excellent performance.
Additionally, a new simulation approach to realize Dolph-Chebyshev linear series-fed DRA arrays by using the advantages of tall microstrip line feeding structure is proposed. By using a novel T shape feeding scheme, the array exhibits wide band operation due to the low permittivity (εr=5) DRA elements and good radiation pattern due to the novel feeding structure. The tall metal transmission line feed structure and the polymer-based DRA elements could be fabricated in a common process by the deep XRL technology.
This thesis firstly illustrates properties and knowledge for both DRA element and the tall transmission line. Then the three novel feeding schemes by using the tall transmission line on exciting the low permittivity DRA are proposed and one of the feeding structures, side coupling feeding, is analyzed through the simulation and experiments. Finally, the T shape feeding structure is applied into low permittivity linear DRA array design work. A novel method on designing the Dolph-Chebyshev array is proposed making the design work more efficient.
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Chiu, Tzu-Ling. "Multiband DRA for automotive applications with beam steering." Thesis, 2017. http://www.theses.fr/2017LIMO0112/document.
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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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Min-Hsi, Chuang. "Dielectric-Resonator- Fed Active Horn Antenna." 2005. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2207200517210100.
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Chuang, Min-Hsi, and 莊閔旭. "Dielectric-Resonator- Fed Active Horn Antenna." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/51237064680284375827.
Full textAbstract:
碩士國立臺灣大學
電信工程學研究所
93
In this thesis, a high directivity active horn antenna is designed and analyzed, and which is implemented by integrating the horn antenna, dielectric resonator and power amplifier. Using DRs in the stripline-to-waveguide transition, signals can couple to stripline or waveguide efficiently. An 8 \% impedance bandwidth and better radiation patterns in the $E$-plane radiation is observed. By integrating power amplifiers into the horn antenna, antenna gain is increased by 7.1 dB without increasing the circuit volume. Chokes are used to reduce the backward radiation. Finally, dual horn antennas are designed and implemented. Sum and difference patterns are also observed as expected. The invention can be applied in many fields such as satellite communication, short term communication, microwave detection system, and signal detector, etc. They can be moduled for extensive application.
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Chen, Tung-Ming, and 陳東明. "Investigation of Integrated Antenna and Wideband Dielectric Resonator Antenna." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/32918298918721493235.
Full textAbstract:
碩士國立成功大學
微電子工程研究所碩博士班
94
In this thesis, wideband polygonal slot antenna and dielectric resonator antenna have been proposed. First part, the design of the polygonal slot antenna for the wideband operation, a small slot is placed on the feed side of wide slot. Experimental results shows that the polygonal slot antenna bandwidth cover most commercial wireless communication, including PCS, IMT-2000 Bluetooth, 802.11a/b/g. Except for the reduce cross polarization, we present the four tuning patch to improve cross-polarization level of antenna radiation pattern. Second part, a compact wide aperture-coupled broadband cylindrical dielectric resonator antenna has been proposed. For improving impedance matching, microstrip feed-line was designed as a fork-like to obtain two resonant modes excitation and lead to a wider impedance bandwidth. Finally, we present an integration of filter and antenna module. This antenna module filters out the out-of-band signals, so that noise figure and size of RF front-end can be reduced.
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Jiang, Dong-Syun, and 江東訓. "Study of wideband rectangular dielectric resonator antenna." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/2xz6hu.
Full textAbstract:
碩士國立臺北科技大學
電腦與通訊研究所
98
A wideband rectangular dielectric resonator antenna coupled with a single microstrip line or a dipole antenna has been studied in this thesis. This study is importance because the impedance bandwidth of one resonant mode of a dielectric resonator antenna with high dielectric constant and high quality factor is mostly insufficient for wireless communication systems. The design has incorporate the characteristic of the microstrip line and rectangular dielectric resonator. The height of the microstrip line is tuned to facilitate optimal coupling with modes of the rectangular dielectric resonator to form a wideband rectangular dielectric resonator antenna. The measured results show the impedance bandwidth is about 12% or 465 MHz from 3610 to 4075 MHz ( Return Loss ≥ 10 dB ), suitable for wideband application. The peak gain of this wideband rectangular dielectric resonator antenna is 6 dBi with a ground plane size of 60 x 60 mm2. A hybrid resonator antenna designed with the same rectangular dielectric resonator exhibits an impedance bandwidth of 39% from 2945 to 4374 MHz. The designed hybrid resonator antenna shows a coverage of the FWA band in WiMAX application with a peak gain of 4 dBi.
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Huang, Jia-chi, and 黃家麒. "Design of Dual-band Dielectric Resonator Antenna." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/exj5q9.
Full textAbstract:
碩士國立中央大學
電機工程學系
103
The dielectric resonator antenna (DRA) has a number of attractive features, such as low loss、light weight、ease of excitation and high quality factor resulting in reducing the wavelength of the resonant mode to achieve small device. DRA has an extensive applications of satellite navigation、area exploration、transmission and reception of satellite television, since it can get higher gain even though as small size. Therefore, it is comprehensively used for small size product. The proposed DRA is used in the C-band. There are often three proposed antenna designs in the literatures: Circular polarization、dual band、and wide band. The goal of this study is to design DRAs of circular polarization and dual band. We can obtain the resonant frequency by theoretical analysis, and the validity of the procedure is verified by using full-wave EM simulation and experiments. Also, we will introduce two feeding methods and stacked DRA. With the proposed design procedure in this study, we intend to offer the design conception and improvement of the related types of antenna.
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Elmegri, Fauzi, Chan H. See, Raed A. Abd-Alhameed, Chemseddine Zebiri, and Peter S. Excell. "Dielectric resonator antenna design for UWB applications." 2013. http://hdl.handle.net/10454/9648.
Full textAbstract:
NoA small dielectric resonator antenna has been designed for ultra wideband (UWB) communication system applications. The antenna element is a rectangular low permittivity ceramic block, with a dielectric constant of 9.4, and the modified T-shaped feed network includes a 50 ohm microstrip line to achieve strong coupling, and some bandwidth enhancement. The antenna performance is simulated and measured over a frequency band extending from 3100 MHz to 5500 MHz; the impedance bandwidth over this interval is 55.8% with VSWR <; 2, making the antenna suitable for UWB applications.
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Chang, Yao-jen, and 張耀仁. "Design of Circularly Polarized Dielectric Resonator Antenna." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/55591111496147121005.
Full textAbstract:
碩士國立中央大學
電機工程學系
104
This thesis presents a circulary polarized dielectric resonator antenna used in the S-band. The cp-DRA S11 bandwidth is 2.33GHz-4.38GHz(61.1%),AR bandwidth is 2.72GHz-3.405GHz(22.3%).Peak gain reached 2.39 dBic. The dielectric constant of the delectric resonator is 10.2. The first part of the thesis describes using the rectangular DRA formula to choose DRA size with 26.1mm*14.3mm*25.4mm, and using High Frequency Structure Simulator (HFSS) to study the resonant modes in the dielectric resonator. Second part is focused on producing cp-DRA by using copper patch in asymmetry feed position, generate 〖TE〗_111^x、〖TE〗_111^y modes in the cp-DRA.The simulation of first cp-DRA S11 bandwidth is 2.58GHz-3.84GHz(39.2%), AR bandwidth is 3.05GHz-3.26GHz (6.6%). Finally, add other one copper patch to adjust electric field amplitude of the two resonant modes, improve AR bandwidth from 6.6% to 19.3%. The simulation of second cp-DRA S11 bandwidth is 2.62GHz-3.49GHz (28.5%), AR bandwidth is 2.87GHz-3.48GHz (19.3%).
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Chen, Jian-Juang, and 陳建庄. "Design and Implementation of Dielectric Resonator Antenna." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/82824527011992078658.
Full textAbstract:
碩士國立臺灣大學
電信工程學研究所
92
This paper presents the design and implementation of cylindrical and ring DRAs, including the measured data compared to the HFSS simulation and empirical formula. The gain of the ring DRA is then by using a cavity reflector. Finally, the design and implement of a single-mode and dual-band DRA is presented.
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Chen, Bo-yuo, and 陳柏宇. "Dielectric resonator broadband antenna for IEEE 802.16e applications." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/06511369307548132035.
Full textAbstract:
碩士國立臺南大學
電機工程研究所
99
Recently, the dielectric resonator antenna has been extensively studied owing to its numerous advantages such as high gain, light and compact size 31×21×5.1 mm3. The shapes of DRAs are various and different, such as hemispherical, cylindrical and rectangular. DRAs can be excited by different feeding method, such as coaxial feed, microstrip line and co-planar lines. The DRAs can be completed low profile due to high dielectric permittivity of the materials. A new wideband rectangular dielectric resonator antenna is proposed. The rectangular dielectric resonator is feed by mircostrip. The antenna provides an impedance bandwidth of 131% for S11 ≦ -8 dB and directional radiation pattern. The antenna characteristics including return loss and radiation patterns were analyzed and discussed. In this thesis, a monopole antenna conformed standard (1.96 ~ 6.17 GHz) is proposed. There is a lower frequency in the mircostrip antenna is created by the high dielectric resonator. There is a fundamental mode in the rectangular resonator which is half-wavelength. The broad bandwidth is because of two close resonator frequencies.
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CHEN, WEN-HONG, and 陳文宏. "Cylindrical Dielectric Resonator Antenna for Wireless Local Area Networks." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/9eb9rq.
Full textAbstract:
碩士國立暨南國際大學
電機工程學系
106
Dielectric resonator antenna with itself has quite high dielectric constant. Thus cause under the same operating frequency. The volume can be better than a microstrip antenna miniaturization. Coupled with dielectric resonator antenna has the characteristics of the resonant cavity. Let the antenna itself under the condition of the smaller, still retain a certain amount of bandwidth and gain. It also the reason why still remain, even if in need of additional cost. This study proposed cylindrical dielectric resonator antenna can be applied to wireless LAN. The material of the dielectric resonator is a kind of ceramics that mix up part of the concentration of alumina. Its dielectric constant is about 9.8. The frequency operation band of the proposed design can cover the high band of wireless local area networks, such as 5.15 GHz to 5.35 GHz and 5.725 GHz to 5.825 GHz range. This Dielectric resonator antenna fed by microstrip line and through a long slot to excite cylindrical resonator modes, and slot itself is not as a radiation element. After calculation, the resonator for HE11 mode.In the end, The impedance bandwidth of proposed antenna is 19.5% (4.86 to 5.91 GHz) and A peak gain of 6.49 dBi are obtained. Antenna radiation pattern traveling in the positive z direction. This design of antenna can cover and applied to WLAN band.
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Lin, Chung-Wei, and 林君蔚. "Dielectric Resonator Antenna Array Utilizing Voltage Control Phase Shifter." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/q9y3f8.
Full textAbstract:
碩士國立臺北科技大學
電子工程系
106
This study proposes a dielectric resonant antenna array. The dielectric resonator has many features, including high dielectric constant, high quality factor, low cost, and low temperature coefficient, which can shorten the resonant path wavelength to achieve the effect of miniaturizing the antenna. This paper is mainly divided into two parts. The first part is circuit design. The main design is power divider and voltage-controlled phase shifter. Both circuits are completed on FR4 board. The basic dielectric constant of FR4 board is 4.3, thickness is 0.8. mm, copper height 0.035 mm. The voltage-controlled phase shifter mainly uses a diode varactor to change the reflection coefficient and then reflect the signal to achieve the purpose of phase modulation, and the variable phase is 190 degrees. The second part is the antenna design, which mainly uses the microwave dielectric resonator combined with the microstrip line feed mode to design the antenna characteristics of the single dielectric resonator antenna element, and then uses two dielectric resonators to be arranged in series to form an antenna array. Finally, an antenna array of four elements is designed. A voltage-controlled phase shifter and a power divider are used to adjust the beam angle to the left and right by adjusting the different feeding phases.
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Song, Yunpeng. "Radiation pattern of aperture coupled prolate hemispheroidal dielectric resonator antenna." Thesis, 2004. http://spectrum.library.concordia.ca/8393/1/MR04400.pdf.
Full textAbstract:
A detailed analysis and study of a prolate hemispheroidal dielectric resonator antenna (DRA) excited by a rectangular slot aperture are developed. The method used is based on the dyadic Green's function technique in the spheroidal coordinates. In this work, the dyadic Green's functions pertaining to a magnetic-current source located in a dielectric spheroid is derived and expressed in a form convenient for numerical computations. The dyadic Green's functions are then employed to formulate the electromagnetic fields radiated by the DRA. The electromagnetic far field is expressed analytically in a compact form. The antenna radiation patterns and directivities are computed for different design parameters. The accuracy of the solution is attested by both comparing with HFSS simulation results and with published data for the corresponding hemispherical dielectric resonator antenna. Furthermore, efficient algorithms for calculating the prolate spheroidal wave functions are developed using the software package MATLAB. The algorithm developed here for calculating the prolate spheroidal function is compact, fast, and efficient, and compared well with other results in the literature.
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Tso-Wei, Li. "Design of Broad-band and Dual-band Dielectric Resonator Antenna." 2005. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0006-2907200502053000.
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Huang, Hsu-Yun, and 黃旭雲. "Manufacturing of zinc titanate dielectric resonator applied to bluetooth antenna." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/r9292e.
Full textAbstract:
碩士國立臺北科技大學
機電整合研究所
98
This study is to use a good microwave dielectric properties of materials, and mixed third compounds enhance its dielectric properties, to make into the use of dielectric resonators and dielectric resonator to microstrip line feed with the same method to make Bluetooth band with dielectric resonator antenna with HFSS simulation software designed to achieve a simple, meeting the needs of the Bluetooth antenna. The study has two parts, first part is using zinc oxide mixture of titanium dioxide, in order to prepare as one with good dielectric property material, any further can improve its Weiboxingzhi mixed with and applied microwave resonance device, tin dioxide by reference Za Zinc may be obtaining the best of titanium microwave dielectric properties of parameters are 28 19,000 quality factor, resonance temperature coefficient 20 ppm / ℃. The second part of the microstrip line feed to match the way to design a microstrip line with dielectric resonator using a dielectric resonator antenna and applied to the Bluetooth frequency band, the best antenna parameters from the center frequency of 2.45 GHz, bandwidth is 54MHz.
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Li, Tso-Wei, and 李作緯. "Design of Broad-band and Dual-band Dielectric Resonator Antenna." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/8883gt.
Full textAbstract:
碩士國立臺北科技大學
電腦與通訊研究所
93
In this thesis, broadband and dual-band antennas by the dielectric resonator are introduced. For broadband antenna, there are four dielectric resonator antennas, antenna one utilize the U-shape slot at feeding terminal to achieve broadband operation. Comparing to the pure slot fed dielectric resonator antenna (same materials), the design can increase impedance bandwidth up to about five times. Antenna two uses the offset of mirostripline feeding and adds a parasitic metal strip, whose the impedance bandwidth can be obtained up to about three times more than the pure microstripline fed one. Moreover, the impedance bandwidth of Antenna three can reach to about seven times by stacking two same dielectric resonators. For dual-band antenna, adding an inverse T-shape parasitic strip can induce two separate resonant points. The radiation patterns are both broadside and no nulls at main radiate direction. The merits of all antennas in this thesis are simple structures and feeding networks, therefore attaining broadband or dual-band characteristics.
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Majeed, Asmaa H., Abdulkareem S. Abdullah, Fauzi Elmegri, Embarak M. Ibrahim, Khalil H. Sayidmarie, and Raed A. Abd-Alhameed. "Rectangular slot fed asymmetric cylindrical dielectric resonator antenna for wideband applications." 2014. http://hdl.handle.net/10454/10734.
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NoTwo Cylindrical Dielectric Resonators DR asymmetrically placed on a thin dielectric substrate and fed by a single rectangular slot for wideband wireless applications are presented. Optimized design procedures were applied within a well-known electromagnetic solver to achieve the improved elements dimensions of the antenna geometry. The simulated and measured results show that the proposed DRA can achieve 29% relative bandwidth at 10 dB return loss covering the spectrum range from 9.62 GHz to 12.9 GHz with a maximum gain of 8 dB.
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Peng, Tsan-Hsuan, and 彭贊軒. "Multi-Resonance and Radiation Characteristics of a Cylindrical Dielectric Resonator Antenna." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/44977352745380196764.
Full textAbstract:
碩士國立臺灣海洋大學
電機工程學系
97
The purpose of this thesis is to exploit the high gain character of cylindrical dielectric resonator antenna (DRA). Dielectric resonator antennas are attractive as alternative to patch antennas because of their small size and wide bandwidth. The DRA offer advantages such as low cost, low loss, ease of manufacture, wider bandwidth, and high radiation efficiency. In this thesis, we have presented two designs for the cylindrical dielectric resonator antenna. The first design was implemented by constructing the DRA with high dielectric constant (�捯 = 27) on a FR4 dielectric substrate. The DRA was excited by a 50Ω microstrip line. The prototype has been fabricated and found to have a good coverage from 5.67 GHz to 5.93 GHz with a bandwidth of 260 MHz and a gain of 6.5 dBi. Our second design utilized the mechanism of multi-resonance to enhance the gain of DRA. In this design, four identical cylindrical dielectric resonators (CDR) were placed on the vertices of a rhombus. The CDR arrangement was then excited by a DRA of same dielectric of the first design. The operation frequency band for the second design was measured and found to operate from 5.61GHz to 5.78 GHz with a gain of 9.4 dBi. The return loss, impedance, polarization and radiation characteristics of the antenna have been investigated using simulation software (HFSS) and the results compare well the experimental measurements.
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Yao, Shi-li, and 姚仕禮. "Improved Microwave Dielectric Properties of Nd(Mg0.5Sn0.5)O3 Ceramics and Application in Dielectric Resonator Antenna." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/28496549908595868374.
Full textAbstract:
碩士龍華科技大學
電機工程研究所
99
In this study, improvement of microwave dielctric properties of Nd(Mg0.5Sn0.5)O3 were investigated. Nd(Mg0.5Sn0.5)O3 ceramics were synthesized and some of the Mg2+ ions were substituted by Co2+, Ni2+, and Zn2+ ions to improve their Q f. Since Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics had a relatively high temperature coefficient of resonant frequency, an investigation involved tailoring the temperature coefficient of resonant frequency of Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics by combining Ca0.8Sr0.2TiO3. B2O3 was added to reduce the sintering temperature of Nd(Mg0.4Zn0.1Sn0.5)O3-0.6Ca0.8Sr0.2TiO3 ceramics. The 1.0 wt.% B2O3-doped Nd(Mg0.4Zn0.1Sn0.5)O3-0.6Ca0.8Sr0.2TiO3 ceramic sintered at 1350 OC for 4 h had a dielectric constant of 38.6, a Q f of 36,200 GHz, and a temperature coefficient of resonant frequency of 0.2 ppm/OC. In the design of dielectric resonator antenna. Combine FR4 substrate with dielectric resonator of 0.4Nd(Mg0.40Zn0.10Sn0.5)O3-0.6Ca0.8Sr0.2TiO3 with 1.00 wt.% B2O3 addition. Dielectric resonator antenna prepare by a coplanar waveguide transmission line. Lowest band has a -10 dB S11 bandwidth of 17.7%(2.309~2.758 GHz). Middle band has a -10 dB S11 bandwidth of 12.4%(3.305~3.741 GHz). Higher band has a -10 dB S11 bandwidth of 14.1%(5.145~5.927 GHz). The radiation patterns are near omni-directional in the x-z plane. But at 5.35 GHz is near broadside radiation pattern. The radiation patternds are near broadside in the y-z plane. But at 5.35 GHz and 5.84 GHz are near omni-directional radiation pattern. In the x-z plane, lowest band has a maximum gain of 1.60 dBi, middle band has a maximum gain of 4.44 dBi, higher band has a maximum gain of 8.30 dBi. In the y-z plane, lowest band has a maximum gain of 2.42 dBi, middle band has a maximum gain of 4.35 dBi, higher band has a maximum gain of 8.29 dBi.
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Chen, Huanyu. "Fast Methods for Millimeter-wave Dielectric Resonator and Antenna Analysis and Design." Thesis, 2009. http://hdl.handle.net/10012/4306.
Full textAbstract:
Ever-increasing interest in millimeter-wave and terahertz spectrum has prompted research and development of novel passive components working at these frequencies. Compared with the conventional planar components, non-planar dielectric devices become more attractive as frequencies increase due to their higher quality factors and dimensional tolerances. In this thesis, we present fast methods to analyze the millimeter-wave dielectric resonator and rod antenna.
First, an analytical method has been developed to evaluate resonant frequencies, quality factors of the Whispering Gallery Mode (WGM) disk resonators and also the resonator-waveguide coupling. A numerical solver based on full-wave finite element method is implemented to verify the analytical result. This analytical model provides a solution for fast design and optimization of WGM resonators in filter and sensor applications.
Secondly, a fast analytical approach based on local mode theory is introduced to calculate the radiation from tapered dielectric rod antenna. This efficient approximate model consumes much less computing resources and time, and demonstrates good agreements with full-wave numerical results. It supplies a quantitative way to understand the radiation mechanism and interaction between different parts of the antenna. Based on this, design criteria for the taper profile of rod antennas are given.