Bandwidth improvement of compact high permittivity RDRA using parasitic conducting strips

This paper presents a compact broadband, low-profile rectangular dielectric resonator antenna (RDRA) using relatively low dielectric constant substrate material. It is developed for wireless communication applications in a WiMAX system at operating frequency band of 5.8 GHz. The DR itself is made of high permittivity material. The RDRA is fed with a modified stepped microstrip line to ensure efficient coupling for better matching. The designed antenna introduces a compact size with reasonable fractional bandwidth 4.3 %, gain of 6.7 dB, efficiency of 92.79 %, and directivity of 7.054 dB. Broadband operation is achieved by loading the DR with a conducting parasitic metallic strip. Parametric investigations for different geometrical variables have been carried out. The DR is also loading the with two narrow parasitic conducting strips for further improve the bandwidth up to 6 % keeping the other parameters in reasonable values. The frequency characteristics and radiation performance of the proposed antenna and the related prototypes are successfully optimized with numerical experimentation techniques using Ansoft HFSS software.