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Reconfigurable 460 MHz to 12 GHz Antenna with Integrated Narrowband Slot
James Robert Kelly;Peter Song;Peter S. Hall;Alejandro Lucas Borja
PIER C , 2011, DOI: 10.2528/PIERC11080410
Abstract: In the future, mobile handsets might incorporate more than 20 separate radios, creating a difficult antenna design problem due to the sever space restrictions. This paper proposes a reconfigurable wideband antenna, for use within clamshell mobile handsets. The impedance bandwidth of the new antenna was selected in order to meet current and future demands within the industry. It has been suggested that a portable Cognitive Radio must be capable of simultaneous communication (via a narrowband antenna) and spectrum sensing (via a wideband antenna). For this reason a narrowband slot antenna has also been integrated within the wideband radiator.
Dielectric Resonator Antenna Mounted on Cylindrical Ground Plane for Handheld RFID Reader at 5.8 GHz
Hend Abd El-Azem Malhat,Saber Zainud-deen,Noha El-Shalaby,Kamal Awadalla
Advanced Electromagnetics , 2012, DOI: 10.7716/aem.v1i3.111
Abstract: Dielectric resonator antenna (DRA) mounted on cylindrical ground plane is investigated for handheld RFID reader applications at 5.8 GHz. The simplicity of the structure makes it practical in terms of cost, space, and ease of fabrication. The radiation characteristics of the antenna in free space and in the presence of a proposed compact reader device model and human hand are calculated. The antenna is circularly polarized and exhibits peak gain of 7.62 dB at 5.8 GHz with high front to back ratio of 15.5 dB. Using the same reader device model, a sequentially feeding 2×2 DRA array mounted on the same cylindrical ground plane is used for RFID reader antenna at 5.8 GHz. The array introduces high gain of 9.36 dB at 5.8 GHz with high front to back ratio of 10.48 dB. The 2×2 DRA array elements exhibit circular polarization over a frequency band of 1.1 GHz. The axial ratio is 1.1 dB at 5.8 GHz. The proposed reader model is simple and has a small size compared with that in the case of planar ground plane. The results are calculated using the finite element method (FEM) and compared with that calculated using the finite integral technique (FIT).
Wideband Polarization Reconfigurable Dielectric Resonator Antenna
Wideband Polarization Reconfigurable Dielectric Resonator Antenna
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Bin Li,Ying Zhou,Mengda Wu,Yuxuan Xia,Yong Liu,Xin Lyu
- , 2017, DOI: 10.15918/j.jbit1004-0579.201726.0407
Abstract: A wideband polarization reconfigurable dielectric resonator antenna excited by quasi-lumped quadrature coupler (QLQC) is proposed. By adjusting the value of varactor diode on the QLQC feed network, both the wideband LP and CP dielectric resonator antennas (DRA) modes can be achieved. By selecting a different feed port, left-and right-handed CP conversion can be realized. It is found that the 10 dB impedance bandwidth of the LP and CP modes are 10.1% and 44.9%, respectively. For the CP mode, a very wide 3 dB axial ratio bandwidth of 37.7% can be obtained which is much larger than that of the microstrip patch counterpart (3.8%). It is worth mentioning that the wideband CP DRA has a stable broadside radiation pattern across the whole operating band where the boresight gain is larger than 3 dBi.
A wideband polarization reconfigurable dielectric resonator antenna excited by quasi-lumped quadrature coupler (QLQC) is proposed. By adjusting the value of varactor diode on the QLQC feed network, both the wideband LP and CP dielectric resonator antennas (DRA) modes can be achieved. By selecting a different feed port, left-and right-handed CP conversion can be realized. It is found that the 10 dB impedance bandwidth of the LP and CP modes are 10.1% and 44.9%, respectively. For the CP mode, a very wide 3 dB axial ratio bandwidth of 37.7% can be obtained which is much larger than that of the microstrip patch counterpart (3.8%). It is worth mentioning that the wideband CP DRA has a stable broadside radiation pattern across the whole operating band where the boresight gain is larger than 3 dBi.
A Wideband Circularly Polarized Patch Antenna for 60 GHz Wireless Communications  [PDF]
Rongguo Zhou, Duixian Liu, Hao Xin
Wireless Engineering and Technology (WET) , 2012, DOI: 10.4236/wet.2012.33016
Abstract: This paper presents the design of a fully packaged 60 GHz wideband patch antenna incorporating an air cavity and a fused silica superstrate. Circular polarization (CP) is realized by introducing a diagonal slot at the center of the square patch. By optimizing the patch and the slot dimensions, a high efficiency (>90%) microstrip fed CP antenna with an impedance bandwidth of 24% and a 6 dB axial ratio bandwidth of 21.5% is designed. A coplanar waveguide (CPW) to microstrip transition with λ/4-open-ended stubs are then designed to match the antenna to the CPW packaging interface. The experimental results of the final packaged antenna agree reasonably with the simulation results, demonstrating an impedance bandwidth of more than 26% and a 6 dB axial ratio bandwidth of 22.7%.
Dielectric Loaded Exponentially Tapered Slot Antenna for Wireless Communications at 60 GHz
Subramaniam Ramesh;Thipparaju Rama Rao
PIER C , 2013, DOI: 10.2528/PIERC13012610
Abstract: This paper deals with the dielectric loaded Exponentially Tapered Slot (ETS) antenna needed for ultra-high-speed, high-capacity wireless communication systems which work at 60 GHz and illustrates its specifications and requirements. The antenna in such system requires high gain, high-efficient and high performance design specifications. The ETS antenna and the loaded dielectric are integrated using the same single substrate resulting in easy fabrication and low cost. The ETS antenna with rectangular and elliptical shaped loaded dielectrics were designed and fabricated. These antennas have high gain and wider beamwidth in both -plane and -plane. The proposed antenna design is simulated using 3D electromagnetic software CST Microwave Studio and the comparison is made with Ansys HFSS to validate the design procedure. The results obtained from the simulations and the measurements are in good agreement.
Multilayer Dielectric Resonator Antenna Transmitarray for Near-Field and Far-Field Fixed RFID Reader
Saber Helmy Zainud-Deen;Shaymaa Mostafa Gaber;Hend Abd El-Azem Malhat;Kamal Hassan Awadalla
PIER C , 2012, DOI: 10.2528/PIERC11121905
Abstract: A design of multilayer dielectric resonator antenna transmitarray for fixed radio frequency identification (RFID) reader applications is presented at 5.8 GHz. Three layers square dielectric resonator antenna (DRA) elements are mounted on dielectric substrate and used as a unit cell in the transmitarray. A circularly polarized 9 × 9 square DRA transmitarray is designed at 5.8 GHz for far-field RFID applications. The transmitarray produces maximum gain of 20.2 dB. The right-hand circular polarization level is lower than -31 dB at the designed frequency with SLL of -22 dB. A design of 9 × 9 near-field focused DRA transmitarray for fixed RFID at 5.8 GHz is investigated. The properties of the near field-focused transmitarray are compared with that of the far field transmitarray designed at the same operating frequency.
8×8 Near-Field Focused Circularly Polarized Cylindrical DRA Array for RFID Applications
Electrical and Electronic Engineering , 2011, DOI: 10.5923/j.eee.20110101.07
Abstract: The design of 8×8 near-field focused circularly polarized dielectric resonator antenna (DRA) array for fixed RFID reader applications at 5.8GHz is presented. The proposed antenna array consists of 64-element of circular dielectric resonator antennas (CDRA) with two orthogonal feeding probes located inside the CDRA element. A single element CDRA with supporting arms used as a building block of the array provide good impedance matching and circular polarization at 5.8GHz. The perforation technique is used for the supporting arms to reduce the manufacturing complexities in the DRA mounting over the ground plane. The sequential feeding technique is used to improve the gain and circular polarization bandwidth of the single element and the array. The characteristics of the near-field focused array are introduced compared to that of uniformly phased array. The finite integral technique and the finite element method are used to compute the array performance
T-Strip FED Patch Antenna with Reconfigurable Polarization
Shun-Yun Lin;Yuan-Chih Lin;Jin-Yan Lee
PIER Letters , 2010, DOI: 10.2528/PIERL10051801
Abstract: In this paper, right handed circular polarization (RHCP), left handed circular polarization (LHCP), and linear polarization (LP) reconfigurable antenna is proposed by reconfigured fabrication. The proposed antenna comprising of two square patches, a T-stripline, and a finite ground plane is designed for HiperLAN2 5 GHz operation. The patches are symmetrically placed along the vertical portion of T-strip and coupling fed by the strip. The planar structure is in LP sense while CP sense is achieved as the structure bent. For the bent structure, the vertical and horizontal portions of T-strip not only respectively feed the coplanar patch but also provide a 90° phase difference between the feeds. Two orthogonal E-fields with quadrature are excited to achieve CP sense. Moreover, the switching between RHCP and LHCP is easily achieved by folding the structure along opposite vertical edge of T-strip. Instead of electrically controlling switches, the polarization reconfiguration can be manually constructed.
Novel Modeling and Design of Circularly Polarized Dielectric Resonator Antenna Array
Mohd Fadzil Ain;Yazeed Mohammad A. Qasaymeh;Zainal Arrifin Ahmad;Mohammad Azman Zakariya;Mohamad Ariff Othman;Seyi Stephen Olokede;Mohd Zaid Abdullah
PIER C , 2012, DOI: 10.2528/PIERC12021801
Abstract: This paper presents a design of circularly polarized dielectric resonator antenna (DRA) array. The dielectric resonators (DRs) were excited by rectangular aperture coupling slots feed with a linear microstrip. The slot positions were determined based on the characteristic of standing wave ratio over a short ended microstrip to deliver the maximum amount of coupling power to the DRs, in order to improve the array gain. Each DR element was rotated 45 with respect to the sides of the exciting slot to generate circular polarization pattern. The DRA array was modeled and simulated as a parallel RLC input impedance component using Agilent (ADS) software, since that will ensure the resonant frequency of the antenna as primary design step before simulating in (CST) software and doing the measurements. The results of the return loss, gain, radiation and pattern axial ratio are shown. The gain of the proposed array in X band was about 8.5 dBi, while the 3dB axial ratio bandwidth started from 8.14 to 8.24 GHz. The impedance bandwidths started from 8.14GHz to 8.26GHz. The proposed DRA exhibited an enhancement of the gain in comparison to a single pellet DRA. The size of the whole antenna structure is about 40 mm X 50 mm and can potentially be used in wireless systems.
Dual-Band Dielectric Resonator Antenna for C and X Band Application
Deepak Batra,Sanjay Sharma,Amit Kumar Kohli
International Journal of Antennas and Propagation , 2012, DOI: 10.1155/2012/914201
Abstract: The proposed technique combines a slot antenna and a dielectric resonator antenna (DRA) to effectively design a dual band dielectric resonant antenna without compromising miniaturization or its efficiency. It is observed that the resonance of the slot and that of the dielectric structure merged to achieve extremely wide bandwidth over which the antenna polarization and radiation pattern are preserved. Here the effect of slot size on the radiation performance of the DRA is studied. The antenna structure is simulated using two simulators (Ansoft HFSS and CST-Studio software). The simulated results are presented and compared with the measured results. This DRA has a gain of 6 dBi and 5.5 dBi at 6.1 and 8.3 GHz, respectively, 10 dB return impedance bandwidth of nearly 4% and 6% at two resonating frequencies and 98% efficiency has been achieved from the configuration. It is shown that the size of the slot can significantly affect the radiation properties of the DRA, and there are good agreements between simulation and measured results.
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