Dielectric resonator antennas—a review and general design relations for resonant frequency and bandwidth

Abstract

Open dielectric resonators (DRs) offer attractive features as antenna elements. These include their small size, mechanical simplicity, high radiation efficiency due to no inherent conductor loss, relatively large bandwidth, simple coupling schemes to nearly all commonly used transmission lines, and the advantage of obtaining different radiation characteristics using different modes of the resonator. In this article, we give a comprehensive review of the modes and the radiation characteristics of DRs of different shapes, such as cylindrical, cylindrical ring, spherical, and rectangular. Further, accurate closed form expressions are derived for the resonant frequencies, radiation Q-factors, and the inside fields of a cylindrical DR. These design expressions are valid over a wide range of D R parameters. Finally, the techniques used to feed DR antennas are discussed.

Investigation on Circularly Polarized Ring Dielectric Resonator Antenna for Dual-Band Wireless Applications

“…From Figure 4, it is confirmed that HEM 11δ and HEM 12δ modes are created inside the ring DRA at 3.0 GHz and 5.8 GHz, respectively [23]. This can also be confirmed by the following mathematical formulation [24]: …”

Laterally Placed CDRA with Triangular Notches for Ultra Wideband Applications

“…The measured S 11 offers the bandwidth of 76.7 %, ranging 4.5 GHz-10.1 GHz. The Radiation quality factor of DRA is inversely proportional to the bandwidth [11], …”

Three Element Dual Segment Triangular Dielectric Resonator Antenna for X-Band Applications

“…The DRA is an open resonating structure, fabricated from a low loss dielectric material. It offers advantages such as small size, high radiation efficiency due to the absence of conductor losses simple geometry, small size, flexible feed arrangement, wide range of material dielectric constant, ease of excitation and easily controlled characteristics As compared with microstrip antenna, the DRA has wider impedance bandwidth and better efficiency due to absence of surface wave [2][3][4][5].…”

“…Bandwidth enhancement is becoming the major design consideration for most practical applications of dielectric resonator antennas [5]. The techniques used to improve the bandwidth of the DRAs include changing the aspect ratio of DRA, modifying feed geometries, employing multi-segments and stacked DRAs and by varying the dielectric constant of DRA material [6,7].…”