Coaxial Fed Half-Split Multilayer Cylindrical Dielectric Resonator Antenna for Wideband Applications Raghvendra Kumar Chaudhary 1 , Gautam Kumar Singh 2 , Kumar Vaibhav Srivastava 3 and Animesh Biswas 4 . Department of Electrical Engineering Indian Institute of Technology Kanpur Kanpur, Uttar Pradesh, INDIA, 208016 Phone No: +91-512-2597319 Abstract—In this paper a wideband half-split multilayer cylindrical dielectric resonator antenna (MCDRA) fed through coaxial probe is developed and discussed. The concept of multi layers is introduced in half-split dielectric resonator antenna for getting wide bandwidth. The design parameters of an antenna such as arrangement of dielectric layers, probe height and DR aspect ratio are investigated. The proposed multilayer cylindrical dielectric resonator antenna is excited with TM 21δ mode. The proposed structure provides ~60% impedance bandwidth for input reflection coefficient (S 11 ) below -10 dB with total gain of 6.09 dB. Keywords- Dielectric Resonators (DRs), Dielectric resonator antenna (DRA), wideband antenna, TM 21δ mode, impedance bandwidth, gain. I. INTRODUCTION Due to number of attractive features of DRA such as low loss, wide-bandwidth, high gain, versatility in their shape and simple feeding mechanism, numerous investigations have been carried out on DRAs in last two decades [1]. In past, DRs were usually treated as an energy storage device and mainly used in microwave filters and oscillators rather than as a radiator or antenna. When DR is placed in open environment then Q-factor reduced significantly and DR act like an antenna because power is lost in radiated fields [2]. The first experimental research is carried out for wideband DRA in 1989 by Kishk et al.. The input impedance of stacked cylindrical dielectric resonator antennas is investigated experimentally and the dielectric resonators made of different materials have achieved the bandwidth of 25% [3]. The Multilayer Cylindrical DRA (MCDRA) approach has also been reported by commercially available materials [4]. The multilayer multi-permittivity approach has been studied for higher mode separation in dielectric resonator in microwave integrated circuit (MIC) environment [5]. The multilayer concept has also introduced in the three elements MCDRA for getting wide input impedance bandwidth [6]. In this paper, we have introduced the multilayer concept of dielectric layers in half-split DR as shown in Fig. 1 for increasing the impedance bandwidth of antenna. The TM 21δ mode is excited in DR antenna. The input reflection coefficient (S 11 ) and absolute gain patterns and of proposed structure are simulated using the Ansoft’s High Frequency Structure Simulator (HFSS), which is a finite-element method based commercial software package. (a) (a) (b) (c) Figure 1. Geometry of proposed wideband half-spilt multilayer dielectric resonator antenna (a). 3D view (b). top view (c). Front view (XX’). Coaxial Probe Multilayer half-split cylindrical DRA ß a X X’ { 1 raghav, 2 singhgk, 3 kvs, and 4 abiswas}@iitk.ac.in 978-2-87487-022-4  2011 EuMA 10 -13 October 2011, Manchester, UK Proceedings of the 41st European Microwave Conference 1015