Frequency-tunable ring dielectric resonator antenna excited by waveguide

A frequency tuning method of ring dielectric resonator antenna is presented in the paper. The basic of proposed method is micro mechanical alteration of the composite ring dielectric resonator. Advantages of the proposed method are the wide range of adjustments and increasing of the radiation efficiency of the antenna. Design of the tunable dielectric resonator antenna excited by waveguide in the standing wave mode is investigated. The basic antenna characteristics, and also analysis of dependencies of the antenna´s central operating frequency, voltage standing wave ratio, bandwidth and radiation pattern versus the relative position of the ring dielectric resonator parts are presented. The influence of the inner to outer ring radius ratio on the efficiency of frequency tuning, radiation efficiency and bandwidth are investigated.