Bandwidth Enhancement of a Circularly Polarized Cylindrical DRA Using Multi-dielectric Layers

Abstract

Compact and highly efficient antennas exhibiting wide operational circularly polarized (CP) bandwidth capability are becoming increasingly popular for current research activity in the wireless communication technology. Dielectric resonator antenna (DRA) remains one of the most attractive candidates for such requirements. In this study, a multilayer DRA configuration using a single point feeding mechanism is proposed for further enhancement of the CP bandwidth. The cylindrical multilayer DRA that is excited using a conformal square spiral conducting metal strip has been studied theoretically and experimentally. Utilizing such antenna configuration has yielded a measured CP and return loss bandwidths of ~5.6 and 15%, respectively. The results represent an additional CP bandwidth increment of ~66% compared to the single layer cylindrical DRA configuration using the same excitation method. Additionally, a good agreement has been attained between the measured and computed results.