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Proceedings ArticleDOI

Composite and Hybrid Dielectric Resonator Antennas: Recent Advances and Challenges

14 Mar 2006-pp 1-7
TL;DR: A general discussion comparing a microstrip patch and a DRA is provided, and some state-of-the-art developments and associated challenges in the DRA design and applications are also discussed.
Abstract: Dielectric resonator antenna (DRA) has been proposed recently as a viable new way to build antenna in view of some of the advantages they offer. One recent trend in DRA research focuses on using composite and hybrid structures. Some considerable investigations are already underway showing quite interesting and significant features. A brief review of the topic is presented in this article. A general discussion comparing a microstrip patch and a DRA is provided in the beginning. Some state-of-the-art developments and associated challenges in the DRA design and applications are also discussed.
Citations
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Journal ArticleDOI
TL;DR: In this article, a new shaped circularly polarised dielectric resonator antenna is proposed, which is easier to implement, free from a complicated feed network and offers wider axial ratio bandwidth.
Abstract: A new shaped circularly polarised dielectric resonator antenna is proposed. This antenna, compared to some previous investigations, is easier to implement, free from a complicated feed network and offers wider axial ratio bandwidth. About 4% AR bandwidth (< 3 dB) with S 11 < -10 dB and 3.5 dBi peak gain is reported.

55 citations

Journal ArticleDOI
TL;DR: In this article, a comprehensive investigation of research carried out on dielectric resonator antennas (DRAs) in the last three and half decades, in an application-oriented approach, is presented.
Abstract: This survey article outlines a comprehensive investigation of research carried out on dielectric resonator antennas (DRAs) in the last three and half decades, in an application-oriented approach. DRAs have created a remarkable position in antenna engineering for their adept characteristics like high efficiency, low loss, wide bandwidth, compact size, 3-dimensional modeling flexibility, etc. The use of DRAs for different commercial and defense applications associated with the wireless communication is highlighted in this article. To make a smooth and effective survey article, all the application-oriented DRAs available in the open literature are classified in five different categories like microwave bands, specific frequency, technology, millimeter-wave, and miscellaneous types. The ultimate aims of this review article are as follows: (i) highlights the usability of DRAs for different commercial and defense applications, (ii) helpful for the antenna industries/manufacturers to find out the best DRA for any specific application as per their requirement, and (iii) points out research gap in some application domains which will be quite helpful for future antenna researchers. In the authors' opinion, this survey may be helpful to DRA researchers as such a survey process is not available in the open literature.

52 citations

Journal ArticleDOI
TL;DR: In this paper, a hybrid dielectric resonator antenna (DRA) excited by a monopole antenna is proposed and implemented to enhance the antenna performance in terms of bandwidth and to create a dipole-shape radiation pattern.
Abstract: A new hybrid dielectric resonator antenna (DRA) excited by a monopole antenna is proposed and implemented. In this structure, three different methods of impedance matching, dielectric, and ground plane shaping are applied to enhance the antenna performance in terms of bandwidth and to create a dipole-shape radiation pattern. The effect of each method to increase the input impedance bandwidth is carefully investigated by an extensive parametric study. The resonant frequencies of the structure are also described and determined. The proposed structure provides more than 5-GHz bandwidth for 10dB return loss ranging from 1.8 to 6.9 GHz. Measurements as well as 3-D simulations were carried out for return loss and antenna radiation pattern, and they show a good agreement.

43 citations

Journal ArticleDOI
TL;DR: In this article, perturbation theory is used to identify difierent types of inclusions that can be used to realize fundamental-mode degeneracy in a rectangular dielectric resonator and thus, can ultimately be used in the design of negative-index metamaterials.
Abstract: The design of resonators with degenerate magnetic and electric modes usually requires the ability to perturb one or both types of modes in order to induce alignment of magnetic and electric properties. In this paper perturbation theory is used to identify difierent types of inclusions that can be used to realize fundamental- mode degeneracy in a rectangular dielectric resonator and thus, can ultimately be used in the design of negative-index metamaterials. For reasons associated with fabrication in the infrared-frequency regime, rectangular resonator designs are of particular interest.

27 citations


Cites background from "Composite and Hybrid Dielectric Res..."

  • ...It is important to recognize that dielectric inclusions of this type have been used previously for bandwidth enhancements [28] and tuning purposes [29, 30]....

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References
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Journal ArticleDOI
TL;DR: In this article, an experimental investigation of the radiation and circuit properties of a resonant cylindrical dielectric cavity antenna has been undertaken, and a simple theory utilizing the magnetic wall boundary condition is shown to correlate well with measured results for radiation patterns and resonant frequencies.
Abstract: An experimental investigation of the radiation and circuit properties of a resonant cylindrical dielectric cavity antenna has been undertaken. The radiation patterns and input impedance have been measured for structures of various geometrical aspect ratios, dielectric constants, and sizes of coaxial feed probes. A simple theory utilizing the magnetic wall boundary condition is shown to correlate well with measured results for radiation patterns and resonant frequencies.

1,434 citations

Journal ArticleDOI
TL;DR: In this paper, a slot antenna and a dielectric resonator antenna (DRA) were combined to improve the available bandwidth of a miniaturized antenna without compromising miniaturization or efficiency.
Abstract: The goal of this study is to improve the bandwidth of a miniaturized antenna. The proposed technique combines a slot antenna and a dielectric resonator antenna (DRA) to effectively double the available bandwidth without compromising miniaturization or efficiency. With proper design it is observed that the resonance of the slot and that of the dielectric structure itself may be merged to achieve extremely wide bandwidth over which the antenna polarization and radiation pattern are preserved. In addition, using the DRA, a volumetric source, improves the radiation power factor of the radiating slot. A miniaturized antenna figure of merit (MAFM) is defined to simultaneously quantify aspects of miniaturized antenna performance including the degree of miniaturization, efficiency, and bandwidth. Figures for various common types of antennas are given and compared with that of the proposed structures. In order to determine the effects of varying design parameters on bandwidth and matching, sensitivity analysis is carried out using the finite-difference time-domain method. Numerous designs for miniaturized slot-fed dielectric resonator antennas are simulated and bandwidths exceeding 25% are achieved. Two 2.4 GHz antennas are built, characterized, and the results compared with theory.

228 citations

Journal ArticleDOI
TL;DR: In this article, a coaxial probe is placed off the antenna axis to excite the HEM/sub 11/spl delta mode in the DRA, resulting in a broadside radiation pattern.
Abstract: The objective of the present study is to improve the bandwidth of the dielectric resonator antenna (DRA) excited by a coaxial probe by using a stacked DRA configuration above an infinite ground plane. The DRA is axisymmetric and a coaxial probe is placed off the antenna axis to excite the HEM/sub 11/spl delta// mode in the DRA, resulting in a broadside radiation pattern. A surface integral equation formulation and the method of moments are used for the numerical analysis. The input impedance and the far field radiation patterns have been computed and the effects of different parameters on the antenna performance have been investigated. With the proper excitation and selection of the resonator parameters, a bandwidth of 35% has been achieved for the stacked DRA configuration based on a -10 dB reflection coefficient on a 50 /spl Omega/-transmission line. An equivalent circuit model is postulated to describe the dual-resonance behavior of the stacked antenna system.

189 citations

Journal ArticleDOI
TL;DR: In this paper, a hybrid antenna consisting of an annular dielectric resonator antenna combined with a quarter-wave monopole to simultaneously act as a radiator and a loading element is presented.
Abstract: A hybrid antenna is presented, consisting of an annular dielectric resonator antenna combined with a quarter-wave monopole to simultaneously act as a radiator and a loading element, producing an ultra wideband response. A prototype antenna is designed and a 3:1 bandwidth is demonstrated.

177 citations

Journal ArticleDOI
TL;DR: In this article, an improved analytical model is presented for calculating the resonant frequency of circular microstrip antennas with and without air gaps, which is widely applicable to all patch diameters-from very large to very small compared to the height of the dielectric medium below the patch.
Abstract: An improved analytical model is presented for calculating the resonant frequency of circular microstrip antennas with and without air gaps. Unlike the previous models, the present one is widely applicable to all patch diameters-from very large to very small compared to the height of the dielectric medium below the patch and also to the substrates covering the entire range of dielectric constants. The computed results for different antenna dimensions and modes of resonance are compared with the experimental values.

123 citations