To see the other types of publications on this topic, follow the link: Circular monopole antenna.
Dissertations / Theses on the topic 'Circular monopole antenna'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 27 dissertations / theses for your research on the topic 'Circular monopole antenna.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Hussain, Asif Jamshaid. "Design of an Ultra Wideband (UWB) Circular Disc Monopole Antenna." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-34605.
Full textAbstract:
My task was to design a circular disc monopole antenna in the Ultrawideband range i.e. 3.1 - 10.6 GHz using the ADS (Advanced Design System) package. In order to achieve the desired matching I simulated dierent sizes of the radiator, feed line and the ground plane of the antenna and observed the current flow in a circular monopole at different frequencies. I did some miniaturization (circular shape and chopping) of the antenna and observed the current flow and radiation pattern in 2D and 3D.
2
N?brega, Clarissa de Lucena. "Otimiza??o dos par?metros de monopolos planares de microfita para aplica??es em sistemas de banda ultra larga." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15200.
Full textAbstract:
Made available in DSpace on 2014-12-17T14:55:07Z (GMT). No. of bitstreams: 1
ClarissaLN.pdf: 3152047 bytes, checksum: a2e14bfa9e4c314444ebb4284dc7608b (MD5)
Previous issue date: 2008-10-21<br>Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior<br>This work presents a theoretical and experimental investigation about the properties of microstrip antennas for ultra-wideband systems. Configurations of elliptic monopoles with different eccentricities and circular monopoles are considered. Two prototypes for each antenna configuration were built, one with the typical microstrip configuration and the other is similar to the first, except for a small aperture in the ground plane. Therefore, this work proposes to modify the configuration of the ground plane of the monopoles designed adding a rectangular stub, in order to optimize and improve the performance of such structures. The obtained results show that the introduction of that rectangular aperture in the ground plane allows an improvement of the frequency response for the considered antenna propotypes. It is observed a good agreement between the measured and simulated results. Finally, some proposals for future works are presented<br>Este trabalho apresenta uma investiga??o te?rica e experimental sobre as propriedades de antenas de microfita para sistemas de banda ultra larga. S?o consideradas configura??es de monopolos el?pticos com excentricidades diferentes, e monopolos circulares. Foram constru?dos dois prot?tipos para cada configura??o de antena, um com a configura??o t?pica de microfita e outro similar ao primeiro, mas com uma pequena abertura no plano de terra.
Assim, este trabalho objetiva modificar a configura??o do plano de terra dos monopolos projetados atrav?s da inser??o de um recorte retangular, para fins de otimiza??o e melhoria nos desempenhos das estruturas. Os resultados obtidos mostram que a introdu??o dessa abertura retangular no plano de terra permite melhorar a resposta em freq??ncia das antenas consideradas. Observa-se uma boa concord?ncia entre os resultados medidos e simulados.
Algumas propostas para a realiza??o de trabalhos futuros s?o apresentadas
3
Silva, Bruna Alice Lima da. "Antenas monopolo planar com patch em anel circular para sistemas UWB." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15320.
Full textAbstract:
Made available in DSpace on 2014-12-17T14:55:43Z (GMT). No. of bitstreams: 1
BrunaALS_DISSERT.pdf: 4847936 bytes, checksum: ecc365df0d6ba32afff7d15a2ae1d14a (MD5)
Previous issue date: 2010-06-14<br>Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior<br>The microstrip antennas are largely used in wireless communication systems due to their low cost, weight, less complex construction and manufacturing, in addition to its
versatility. UWB systems have emerged as an alternative to wireless communications over short distances because they offer of higher capacity and lower multipath distortion than
other systems with the same purpose. Combining the advantages of microstrip antennas to the characteristics of UWB, it is possible to develop more and more smaller devices, with diverse geometries to operate satisfactorily in these systems. This paper aims to propose alternatives to microstrip antennas for UWB systems operate in the range between 3.1 and 10.6 GHz, with a patch on circular ring. Some techniques are analyzed and employed to increase the bandwidth of proposed antenna: the insertion of a parasitic elements and a rectangular slit in the displaced ground plane. For this, key issues are presented as the basic principles of UWB systems, the fundamental theory of antennas and microstrip antennas. The simulations and experimental characterization of constructed antennas are presented, as well as analysis of
parameters such as bandwidth and radiation pattern<br>As antenas de microfita s?o amplamente utilizadas nos sistemas de comunica??o sem fio devido ?s suas caracter?sticas de baixo custo, peso, menor complexidade de constru??o e fabrica??o, al?m de sua versatilidade. Os sistemas UWB surgiram como uma alternativa ?s comunica??es sem fio de curtas dist?ncias por oferecerem maior capacidade e menor distor??o por multipercurso que outros sistemas com a mesma finalidade. Aliando as vantagens das antenas de microfita ?s caracter?sticas do UWB ? poss?vel desenvolver dispositivos cada vez menores e com geometrias diversificadas para operar satisfatoriamente nesses sistemas. Este trabalho tem como objetivo propor alternativas de antenas de microfita para operar em sistemas UWB, na faixa entre 3,1 e 10,6 GHz, com patch em anel circular. S?o empregadas e analisadas algumas t?cnicas para aumentar a largura de banda das antenas propostas: a inser??o de elementos parasitas e de uma fenda retangular no plano terra deslocado. Para isto, s?o apresentados temas fundamentais como os princ?pios b?sicos dos sistemas UWB, a teoria fundamental de antenas e antenas de microfita. S?o apresentadas as simula??es e caracteriza??es experimentais das antenas constru?das, bem como uma an?lise de par?metros como a largura de banda e o diagrama de radia??o
4
Barreto, Edwin Luize Ferreira. "An?lise do acoplamento de estruturas fractais em antenas monopolo multi-banda para comunica??o sem fio." PROGRAMA DE P?S-GRADUA??O EM ENGENHARIA EL?TRICA E DE COMPUTA??O, 2016. https://repositorio.ufrn.br/jspui/handle/123456789/22329.
Full textAbstract:
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-17T19:09:01Z
No. of bitstreams: 1
EdwinLuizeFerreiraBarreto_TESE.pdf: 4396827 bytes, checksum: 67d20b4064513759f618b9148557fcdd (MD5)<br>Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-17T21:47:01Z (GMT) No. of bitstreams: 1
EdwinLuizeFerreiraBarreto_TESE.pdf: 4396827 bytes, checksum: 67d20b4064513759f618b9148557fcdd (MD5)<br>Made available in DSpace on 2017-03-17T21:47:01Z (GMT). No. of bitstreams: 1
EdwinLuizeFerreiraBarreto_TESE.pdf: 4396827 bytes, checksum: 67d20b4064513759f618b9148557fcdd (MD5)
Previous issue date: 2016-11-18<br>Este trabalho tem como objetivo principal realizar o estudo e an?lise de diferentes antenas planares de microfita, atrav?s do emprego de geometrias fractais no patch ressoador e da remo??o parcial do plano de terra com acoplamento. Recentes estudos mostram que as varia??es nas formas geom?tricas do patch da antena e do plano de terra produzem mudan?as na distribui??o da densidade de corrente da estrutura e consequentemente nos modos ressonantes e na polariza??o da antena. No desenvolvimento desta tese, apresenta-se uma nova antena fractal que utiliza a t?cnica de inser??o de fendas e aberturas de forma fractal no plano de terra e tamb?m descontinuidades no transformador ? de onda na linha de transmiss?o a fim de aumentar a largura de banda e alcan?ar comportamentos espec?ficos em aplica??es de banda de frequ?ncia. Emprega-se o substrato FR-4 com dimens?es de 85,0 x 85,0 x 1,57 mm?. Al?m disso, usam-se diferentes modos de casamento de imped?ncia na linha de alimenta??o de antena como CPW (Coplanar Wave Guide) e altera??es da largura da linha de transmiss?o, a fim de obter varia??o na distribui??o de corrente e, consequentemente, na largura de banda de resposta por imped?ncia para S11 ? -10dB para banda C (3.9 GHz - 6,2 GHz) e banda S (2,0 GHz - 4,0 GHz). Uma an?lise comparativa de desempenho para a linha de microfita e CPW foi realizada, obtendo-se para alguns casos antenas circularmente polarizadas. Boa concord?ncia foi obtida entre os resultados medidos e simulados.<br>This work has as main objective to carry out the study and analysis of different planar microstrip antenna, by employing fractal geometry in the resonator patch and partial removal of the ground plane with coupling. Recent studies show that variations in geometric shapes of the antenna and the ground plane generate changes in current density distribution of the planar structure and consequently the resonant modes and antenna polarization. In developing this thesis presents a new fractal antenna using the technique of insertion slots and fractal shaped defects (gaps) in the ground plane and discontinuities with ? wavelength transformer in the transmission line in order to increase the bandwidth and inserting in the feed line to reach specific behaviors in three frequency bandwidth applications. We used the FR-4 substrate with dimensions of 85.0 x 85.0 x 1.57 mm?. In addition, we used different modes of impedance matching in line antenna feed as CPW (Coplanar Wave Guide), to change the width of the transmission line in order to obtain a variation in the current distribution and hence the response bandwidth impedance to S11 ? -10dB for C band (3.9 GHz - 6.2 GHz) and S band (2.0 GHz - 4.0 GHz). A comparative analysis of cases with microstrip line and CPW was made, applications in this frequency range require preferably circularly polarized antennas. Good agreement was obtained between measured and simulated results.
5
蔡文益. "Broadband Fractal Circular-Monopole Antenna." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/ejrb2e.
Full textAbstract:
碩士<br>景文科技大學<br>電腦與通訊研究所<br>99<br>In this paper, a novel broadband Fractal circular-monopole antenna is presented. This antenna consists of printed circular iteration with two iterating level and ground-plane with radius 25mm, making it easy to making it easy to combine directional, high gain and wide bandwidth. A prototype is designed to operate at 1.5GHz-5.86GHz, the measured 10 dB bandwidth is nearly 1:2 at the center frequency of 3.775GHz. Experimental results are shown to verify the validity of theoretical work.
Fractal monopole antenna is formed with hollow of circle, which featuring of minification, multi-frequency bands and wide bands.
The planar fractal monopole antenna is based on the Sierpinski carpet concept and to modified, the Sierpinski fractal has generated two iterations, use the decomposition algorithm by circular, and compare these with integrators and initiator type. Firstly, base on generally circular disc to generate hollow of circular, this initiator has a circumference of and 1mm trace width. In the decomposition algorithm, a geometric ratio of circle is taken and joining the midpoints of union of the circles central, reduce the circle to 1/3 diameter and canonical Sierpinski carpet algorithm to fill the circle with twice mathematics equals 1/9 diameter by 2nd iteration.The geometrical structure and dimensions of the proposed monopole type antenna is printed on FR4 substrate and is simulated by using FEM based electromagnetic simulator, Ansoft HFSS.
All of them describe a multiband behavior of fractal antenna. This behavior is consistent from the input return loss and gain; moreover radiation patterns planes of view. The same scale factor existing among similar structures in the fractal circular-shape. It can be summarized that the self-similarity properties of the fractal structure are translated into its electromagnetic behavior. The current density distributions have a similar and vary in complicated among bands as well. Such distributions allows flexibility in matching multi- and width band operations in which a larger frequency required, such as FemtoCell and UMTS base station application including LTE, UMTS, GPS L1, WIFI, and WiMax. The circular monopole type is based on fractal structure and refers to the Sierpinski gasket self-similarity algorithm, a prototype of the design is successfully implemented with close agreement between measurement and simulation. The fractal geometry and overall size can be effectively utilized ID or Logo surface for integrating with other components in IT products.
6
WANG, JIAN-CHENG, and 王健丞. "CPW Monopole Antenna Application Circular Polorization." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/26wa3a.
Full textAbstract:
碩士<br>大葉大學<br>電機工程學系<br>104<br>This paper presents to the CPW fed monopole antenna can be use in global positioning system(GPS)and 4G(LTE).This antenna thourgh suitable cutting one side of a metal ground plane, so that the original monopole resonance disappears, forming a dipole resonance, and output and has two orthogonal linearly polarization 90° to achieve circular polarization. On the other side of the metal ground plane, with inverted L-shaped metal patch antenna bandwidth is increased so that the coating on the 4G(LTE)band.In addition, the antenna design can be simple,low -cost production, and easy to combine with the microwave components.
7
TSENG, BO-FEI, and 曾泊斐. "Analysis of Planer Circular Polarization Monopole Antenna." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/tsvysu.
Full textAbstract:
碩士<br>大葉大學<br>電機工程學系<br>105<br>In this research, Different circularly polarized structures are studied on monopole antennas. The circular polarization characteristics are generated by different structures. The first antenna produces a wideband circular polarization characteristic using an offset feed current. The second antenna produces dual-band circular polarization characteristics by an orthogonal structure coupled to the diamond - shaped ground plane. The third antenna produces dual-band circular polarization characteristics using an asymmetric ground plane and a special structure. Frequency bands in this study include WLAN, WiMAX, LTE, etc. The operable frequency band is based on a reflection coefficient below -10 dB and an axis ratio below 3 dB.
8
Liang, Yi-chung, and 梁議中. "Ultra-broadband CPW-fed circular monopole antenna." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/67601833182890315268.
Full textAbstract:
碩士<br>國立中央大學<br>電機工程研究所<br>95<br>A ultra-broadband, planar, circular monopole antenna (PCMA) fed by coplanar waveguide (CPW) structures is demonstrated. The CPW configuration permits easy integration with the uniplanar monolithic integrated circuits/monolithic microwave integrated circuits. Two modifications on the CPW ground plane are applied to improve the impedance bandwidth and radiation characteristics of the CPW-fed PCMA. First, the edges around the circular monopole are tapered to drastically increase the impedance bandwidth. Plus, the antenna gain is increased at the lower frequencies of the band. Second, the tapered edges are corrugated with rectangular gratings to significantly improve the radiation patterns, particularly at the frequencies around the higher band edge. The demonstrated CPW-fed PCMA features an over 151% VSWR=2 fractional bandwidth and satisfactory radiation characteristics over the whole band.
9
Yeh, Jing-pei, and 葉璟霈. "Coplanar Waveguide fed Circular Polarization Slotted Annular Ring Monopole Antenna." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/96121392848674553596.
Full textAbstract:
碩士<br>國立中央大學<br>電機工程研究所<br>98<br>The design and analysis of a planar, circularly polarized, and slotted annular ring monopole antenna are presented. In contrast to traditional planar circularly polarized patch antenna and slot antennas poised for narrowband applications, the presented antenna is of relatively broad operating bandwidth by exploiting the broadband monopole antenna structure. Specifically, the proposed antenna consists of a coplanar-waveguide (CPW) fed annular ring monopole with a gap near the CPW feed. The circular polarization is essentially realized with the circular current flow on the slotted annular ring and the unsymmetrical surface current on the ground plane. Furthermore, additional circularly polarized operation bands can be realized with the incorporation of stretched-out quarter-wavelength inverted-L sleeves on the ground plane edges. In this thesis, a single-band and a dual-band CPW-fed slotted annular ring monopole antennas are demonstrated. The single-band antenna features circular polarization at the L1 band, while the dual-band antenna is of circular polarization at the L1 band, as well as at 1.96 GHz. In addition, both antennas is of operating frequencies ranging from 1.5 GHz to 3 GHz for the GPS, DCS, PHS, WCDMA, and Bluetooth applications.
10
HSU, CHIA-WEI, and 許家瑋. "Theory and Design of the Compact Monopole Antenna for Circular Polarization." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/76208960701233513359.
Full textAbstract:
碩士<br>國立臺南大學<br>電機工程學系碩博士班<br>105<br>Theory and Design of the Compact Monopole
Antenna for Circular Polarization
Student：Chia-Wei Hsu Advisor(s)：Professor Chien-Jen Wang
Master’s Department of Electrical Engineering , National University of Tainan
ABSTRACT
In this thesis, a coplanar-waveguide (CPW)-fed dual-band antenna for applications of the multi-system integration has been demonstrated. The resonance analysis of the stepped-impedance (SI) monopole is presented by using the transmission-line analysis method. The frequency-response characteristics of the SI-monopole, such as the resonance condition and harmonic response, are systematically summarized. Furthermore, utilizing several techniques, such as bent monopole, asymmetric ground plane, and an L-shaped slot etched in the ground plane, a right-hand circularly polarized (RHCP) radiating wave at 1.57 GHz and a left-hand circularly polarized (LHCP) radiating wave at 2.33 GHz are excited for the global positioning system (GPS) and the satellite digital audio radio (SDAR) service system.
After optimization of the geometrical parameters of the proposed antenna, the measured impedance bandwidths of a reflection coefficient < - 10 dB range from 1.40 to 2.98 GHz and from 4.48 to 6.27 GHz, and thus covers most of the commercial wireless communication systems, such as GPS, DCS, PCS, SDAR, IMT-2000, WLAN, and LTE 2300/2600. The measured 3-dB axial ratio (AR) bandwidths are about 80 MHz at 1.57 GHz and 100 MHz at 2.33 GHz.
Keywords：Stepped impedance, transmission-line analysis method, resonance condition, harmonic response, and axial ratio.
11
Shao, Che-Min, and 邵哲民. "Design of Ultra-wideband monopole antenna with WLAN band-notched and GPS circular polarization characteristics." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/68290811033668786532.
Full textAbstract:
碩士<br>逢甲大學<br>通訊工程所<br>96<br>In this thesis we proposed the use of a printed disk monopole antenna with coplanar waveguide (CPW) feeder for ultra-wideband (UWB) and global positioning system (GPS). The frequency band assigned for UWB system by FCC is between 3.1 to 10.6 GHz and this will cause interference to the existing wireless communication systems. For instance, the wireless local area network (WLAN) for IEEE 802.11a operating in 5.15–5.35 GHz and 5.725–5.825 GHz bands. Therefore a UWB antenna with a band-notch is required to overcome the interference. The antenna is constructed with the conventional radiating disk element that should benefit from the ease of manufacturing process and at the same time be cost effective. In addition, an annular stub is implemented to achieve circular polarization (CP) for GPS application at 1.575 GHz. The characteristics of axial ratio (AR) can be optimized by tuning the stub length and the stub-radiating element distance. As this design AR < 3 can be achieved for the frequency range from 1.55 to 1.58 GHz. By modifying the edges of the ground, the antenna is observed to provide an enhanced impedance bandwidth. The band-stop characteristic is realized by cutting an inverted U shaped slot on the radiating disk. The frequency of stop-band can be adjusted by changing the length and width of the inserted slot. The impedance bandwidth of the proposed antenna can range from 1.4 GHz to 11 GHz while the band rejection characteristic falls in the frequency band of 4.8 GHz to 5.98 GHz. Since the antenna presents a notched band from 4.8 to 5.98 GHz, it can prevent the RF interference from the wireless local area network (WLAN) as specified by IEEE 802.11a. This proposed antenna shows a monopole-like radiation pattern and good agreement has been obtained between the simulation and experiment results.
Finally, a periodic structure is proposed. The characteristics of different periodic amount texture is studied. The back of antenna put the period of the surface texture is applied. The texture is put the back of monopole antenna with circular polarization, when the dimension of structure is large and the amount of the structure is less, the resonance of frequency is influenced, because the structure is the parasitic radiator. Contrary, when the dimension of structure is small and the amount of the structure is more, the resonance of frequency is higher, the of antennas are uninfluenced. This structure with the characteristics of high impedance surface, size reduction.
12
HUANG, XIAN-JIE, and 黃賢杰. "Application of the finite-difference time-domain method for the solution of the electromagnetic boundary value problem of the circular diffraction antenna and the cylindrical monopole." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/85021720467030919667.
Full text
13
Huang, Hao-Shiang, and 黃晧翔. "Circularly Polarized Monopole Antenna Designs." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/07486773061579913898.
Full textAbstract:
碩士<br>國立高雄海洋科技大學<br>電訊工程研究所<br>102<br>In this dissertation, circularly polarized (CP) monopole antenna designs for industrial, scientific and medical (ISM) band are proposed. First, by properly introducing dual strip-sleeves shorting at the ground plane, the antenna design provides the impedance bandwidths (RL≧10 dB) of 270 / 988 MHz and the 3 dB axial-ratio (AR) bandwidth of about 85/710 MHz for 2.4/5.2 GHz wireless local area network (WLAN) applications, respectively. The proposed planar antenna reduces the antenna size by at least 22% since the overall antenna size is only 40 × 40 × 1.6 mm3. Meanwhile, the measured peak gains and antenna efficiencies are about 4.2/3.2 dBic and 95/90% across the operating bands, respectively. Next, two spiral monopole antennas with radial and axial circular polarization, respectively, are proposed with the impedance bandwidth of 135/218 MHz and the 3 dB axial-ratio (AR) bandwidth of about 108/125 MHz across 2.45 GHz operating band. Furthermore, the measured peak gains and antenna efficiencies are about 9/10 dBic and 85/80%, respectively. Finally, the analysis of the body specific absorption rate (SAR) for two proposed spiral monopole antennas are discussed and less than 1.6W/kg for 1-g body tissue.
14
CHEN, GUAN-LIN, and 陳冠霖. "Circularly Polarized Monopole Antenna Designs." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/80716486991789568103.
Full textAbstract:
碩士<br>逢甲大學<br>電機工程學系<br>105<br>This paper studied the circularly polarized RFID reader antenna. The first antenna is a compact circularly polarized monopole antenna. It is fed by a microstrip line. By adjusting the parameters of the left branch and right branch, a circularly polarization with good impedance matching can be obtained. The overall dimension of the first proposed antenna is 60×60×0.8 mm3. The measured 10-dB return loss bandwidth of the antenna is 93.4 MHz (901 – 993.4 MHz, 9.3%), 3-dB axial ratio bandwidth is 12 MHz (916 – 928 MHz, 1.3%), the maximum gain and radiation efficiency are -1.1 dBic and 70%, and antenna has bidirectional radiation characteristics. The half-power beamwidths antenna in XZ plane and YZ plane are 170 degrees and 115 degrees respectively. The first proposed antenna is a low profile, compact size, low cost antenna, which is suitable for portable UHF RFID reader application.
The second proposed antenna uses AMC reflector to enhance the gain of the antenna. The AMC reflector periodic structure is placed 9 mm away from the bottom of the antenna for the optimal configuration. The measured 10-dB return loss bandwidth is 650 MHz (2.08 – 2.73 GHz, 27%), 3-dB axial ratio bandwidth is about 120 MHz (2.6 – 2.72 GHz, 4.5 %); the best axis ratio is 1.29 (2.65 GHz), and the measured gain is 6.5 dBic. The front-to-ratios in XZ plane and YZ plane are both about 22 dB. The overall dimension of the second antenna is 80×80×12.2 mm3.
15
Lin, Yen-Chih, and 林彥鋕. "CPW-Fed Circularly Polarized Monopole Antenna." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/36587086447920777634.
Full textAbstract:
碩士<br>逢甲大學<br>產業研發碩士班<br>95<br>In this thesis, a CPW-fed circularly polarized monopole antenna has been implemented and investigated. The simulated and measured results of the antennas are detailed and analyzed.
First, a new antenna possessing linear polarization and circular polarization for applications of the global positioning system (GPS) and digital communication system (DCS) has been designed. The proposed antenna consists of two parts: a quasi-C-shaped monopole antenna and an inverted L-shaped strip connecting to ground plane. By introducing a gap between the monopole antenna and inverted L-shaped strip, a traveling-wave current is excited on a loop trace. Meanwhile, by utilizing the electromagnetic coupling effect inside the gap, the vertical and horizontal electric fields with the phase difference of 90 degree and the equal magnitude result in the circularly polarized radiation in the free space at the 1.5 GHz band (GPS). The resonant band at 1.8 GHz (DCS band) is determined by the effective length of the quasi-C-shaped monopole antenna. Finally, the optimal dimensional values of the antenna are derived by tuning the critical parameters in order to obtain the maximum bandwidth and desired circular polarization。
The advantages of the new proposed antenna are miniaturization, dual-system operation, circular polarization and easy fabrication. The proposed antenna can be a candidate of the RX/TX radiator for the integration of GPS and DCS systems.
16
LU, BO-RU, and 盧柏儒. "Broadband C-Shaped Circularly Polarized Monopole Antenna." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/87950526255852096732.
Full textAbstract:
碩士<br>大葉大學<br>電機工程學系<br>104<br>This thesis discusses is designed and improve the Broadband C-Shaped monopole. The antenna is reference by C-Shaped, and add a rectangle and open-loop in ground plan to achieve width bandwidth and axial ratio. Advantages of the antenna are simple structure, compact size , width bandwidth and axial ratio. Objective to cover the WLAN 5 GHz (4.915 - 5.825 GHz) bandwidth.
17
Chen, Pei-Wen, and 陳姵妏. "A V-Shaped Circularly Polarized Monopole Antenna." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/91914493608976082208.
Full textAbstract:
碩士<br>大同大學<br>通訊工程研究所<br>100<br>This thesis presents a broadband circularly polarized antenna. The antenna is a V-shaped monopole fed by a microstrip line. The V-shaped design is modified from a reference antenna which contains a vertical and a horizontal arm fed by a microstrip line. By tuning the angle between the two arms, a critical angle yielding a broadband circularly polarized wave can be found. To improve the overlapped return-loss and axial-ratio bandwidth, a slit is cut on the ground plane. It is measured that the return-loss bandwidth is 23% and the axial-ratio bandwidth is 30%.
18
Lee, Wei-Chih, and 李偉誌. "A NOVEL DUAL-BAND CIRCULARLY POLARIZED MONOPOLE ANTENNA." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/31332357312662293023.
Full textAbstract:
碩士<br>大同大學<br>通訊工程研究所<br>100<br>A WLAN circularly polarized antenna is presented. The antenna features to have a monopole-like structure fed by a microstripline on a slit-loaded ground plane. There are also two protruded arms extended from two edges of the ground plane. It is investigated that the two arms are mainly responsible for the low-part band of this dual-band antenna. While tuning two slits on the monopole, a high-part band is formed. By this way, the dual band circular polarized antenna covers two ISM bands centered at 2.45 GHz and 5.5 GHz.
19
Zhou, Zhi-Hong, and 卓智弘. "Studies on Broadband Circularly Polarized Monopole Antennas." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/48402208543667088488.
Full textAbstract:
碩士<br>雲林科技大學<br>通訊工程研究所碩士班<br>99<br>This thesis presents a broadband circularly polarized（CP）printed monopole an-tenna can be applied to satellite communications system operations, and to improve the antenna gain by a back cavity design. The main features of the monopole antenna with CPW-fed a L-shaped feeder is folded, a circular metal patch, and then implanted the perturbation of a rectangular structure under the circular metal patch. Extension of the design steps to adjust the number of parameters, the antenna radiation characteristics to produce RHCP, and with more than 35 % 3 dB axial ratio bandwidth.
In addition, to improve the antenna gain, we propose a second antenna, placing a back cavity behind the monopole antenna. The back cavity is constucted with a metal plate the metal wall on the four edges of the metal plate. Through this simple design and easy to make, we can still get more than 90 % of the original CP bandwith. However, the antenna gain increase over 5~7 dB of the antenna gain.
20
Huang, Chien-Rung, and 黃建榮. "Compact leaky-wave antenna and dual-band circularly polarized slotted monopole antenna." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/91288063850864701112.
Full textAbstract:
碩士<br>國立交通大學<br>電信工程研究所<br>100<br>This thesis consists of two parts：1. Using split ring resonators to suppress the side-lobe level of the tapered compact leaky wave antenna. And 2. Using the structures of slots to excite dual-band circularly polarization in monopole antenna. In the first part, we demonstrate two types of suppressing the reflection wave of the leaky wave antenna. The first structure is to put the split ring resonators at the open end of the leaky wave antenna, and the split ring resonators can generate stop-band to suppress the side-lobe level efficiently. The second structure is to etch the split ring resonators in the ground plane, and the reflected wave will couple to the split ring resonators and be trapped. Thus it can be seen that we can use split ring resonators not only to suppress the side-lobe but also to reduce the length of the leaky wave antenna.
In the second part, a dual-band circularly polarized monopole antenna using structures of slots will be introduced. The main structure of the monopole antenna is a circular strip and we add a circular patch at the end of the strip. In the ground plane, we etch a L-shaped slot, and this slot play an important role of exciting the circular polarization not only at the lower band but also at the upper band. The most important is that we can choose the different length of the L-shaped slot to operate on the frequency band what we want. On the other hand, we also add two notches at the antenna, and these two notches can adjust the operating frequency band of circular polarization at the upper band. From the above, we can use these simple structures to get circular polarizations.
21
Yang, Chih-Chieh, and 楊智傑. "New Circularly Polarized Monopole Antennas for GPS Applications." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/14863051179178732557.
Full textAbstract:
碩士<br>大葉大學<br>電機工程學系<br>98<br>This thesis proposes a new microstrip-fed circularly polarized printed antenna for global positioning satellite (GPS) receivers. The antenna consists of two orthogonal monopoles, generating two orthogonal linearly polarized waves of equal amplitudes and with a 90-degree phase shift in the operation band. In contrast to typical GPS patch antennas, the proposed antenna has much wider axial ratio bandwidth. In addition, the antenna can be simply designed, cost-effectively manufactured, and easily merged with the related circuit board. A prototype antenna was created and investigated, and the experimental results obtained demonstrate its low sensitivity to manufacturing uncertainty.
22
Lin, Jhen-Hong, and 林震鴻. "Studies on Dual-Broadband Circularly Polarized Monopole Antennas." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/28739903281054796462.
Full textAbstract:
碩士<br>國立雲林科技大學<br>電機工程系碩士班<br>101<br>This thesis presents a broadband and a dual-band circularly polarized (CP) printed monopole antenna design for GNSS and INMARSAT systems, as well as a back cavity design which is used to improve the antenna gain. Through a few simple design steps starting from a basic monopole antenna which does not have circular polarization characteristics originally, the designed CP monopole antenna having a small radiator size can achieve a 3-dB axial-ratio bandwidth more than 35.2%.
In addition, on the basis of the broadband CP monopole antenna mentioned above, we have also developed two dual-band CP monopole antennas with their dual-band frequency ratios controllable. For the antenna with its two CP bands created using a band-notch mechanism, the achieved dual-band frequency ratio is low. For the other with its two CP bands created by moving the upper portion of the wide CP band toward a higher frequency, the resulting dual-band frequency ratio is slightly higher.
Finally, in order to improve the antenna gain, we put a back cavity with metal sidewalls behind the monopole antennas. It can not only reduce the backward radiation by more than 20 dB but also increase the antenna gain by more than 6 dBic.
23
謝侑霖. "Circularly Polarized Monopole Antenna Designs for UHF RFID System Applications." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/54982505498304708230.
Full text
24
陳聖文. "Design of Planar Circularly Polarized Monopole Antenna by Coupling Structure." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/w6qj3e.
Full textAbstract:
碩士<br>大葉大學<br>電機工程學系<br>106<br>In this paper mainly studies and designs circularly polarized antennas. The circular polarization characteristics are generated by a special structure. The first antenna uses a polygon as the antenna pole structure to generate a circular polarization effect by means of asymmetry and coupling. The second antenna uses radiated energy to scoop, and the circular polarization characteristics are achieved by the cyroid ring ground plane. The third branch uses antenna offsets to achieve asymmetry to produce circular polarization. The frequency bands for this study include Wireless LAN, Long Term Evolution, and Ultra High Frequency. The operable frequency band is based on a reflection coefficent below -10 dB and an axis ratio below 3 dB .
Key Words : Dual Band Circular polarization, CPW feed, Ultra Highg Frequency (UHF), Wireless LAN( WLAN), Long Term Evolution (LTE)
25
Liau, Geng-Yi, and 廖耕億. "A Study on Compact Dual-Band Circularly Polarized Monopole Antennas." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/15573748980124549613.
Full textAbstract:
碩士<br>國立雲林科技大學<br>電機工程系碩士班<br>101<br>This thesis presents the design of a broadband and a dual-band circularly polarized (CP) antenna for GNSS and INMARSAT applications. Through a few simple development steps, the first CP antenna was designed to have a small size of only 0.048?軩2, yet its 3-dB axial-ratio bandwidth is up to 48%.
On the basis of the broadband CP monopole antenna mentioned above, we have also developed a dual-band CP monopole antenna with dual-band frequency ratio controllable. For that purpose, a band-notch structure is embedded in the first CP antenna to result in two broad CP bands. The achieved dual-band frequency ratio is low enough so that the antenna is suitable for GNSS and INMARSAT applications.
26
CHAO, ZIH-SYU, and 趙紫旭. "Dual-Band Circularly Polarized Planar Monopole Antennas for WLAN Application." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/wvv75a.
Full textAbstract:
碩士<br>國立高雄應用科技大學<br>電子工程系碩士班<br>104<br>In this thesis, dual-band circularly polarized planar monopole antennas designs are proposed for 2.4 GHz, 5.2 GHz and 5.8 GHz WLAN applications. The proposed configurations are based on the printer monopole antenna to design a circularly polarized (CP) radiation. In Chapter 2, two antenna configurations are proposed for dual-band circularly polarized operations in WLAN applications. The first design uses a microstrip line fed to radiation monopole with two F-shaped branches, and adds the asymmetrical ground plane to U-shaped parasitic element produced dual-band CP effect. The second CP antenna design consists of a C-shaped monopole with a microstrip feedline, a rectangular parasitic element, and a step ground plane with an inverted L-shaped strip. In Chapter 3, a trigeminal-shaped monopole antenna is proposed using a CPW fed structure with an L-shaped ground plane to achieve dual-band CP operation.
27
Sun, Chih-Chiang, and 孫志強. "BROADBAND CIRCULARLY POLARIZED ANTENNA THROUGH COUPLING OF AN L-SHAPED MONOPOLE TO A U-SHAPED STRIP RING." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/37224259032639347067.
Full textAbstract:
碩士<br>大同大學<br>電機工程學系(所)<br>99<br>In this thesis, a wideband circularly polarized antenna for WiMAX and WLAN band applications is presented , this antenna uses an inverted L-shaped monopole coupling to a U-shaped strip ring the strip ring is etched on the back side of the monopole, this antenna operates a return–loss bandwidth of 1.9GHz(2.1-4.0GHz) and an axial-ratio bandwidth of 1.8GHz (2.1-3.9GHz) and the peak antenna gain in 2.1-3.9GHz is around 1.75dBic to 3.75dBic .