A Ka-band circularly polarized dielectric resonator modelled using the transmission-line-matrix method

摘要

A circularly polarized dielectric resonator antenna has been developed recently for K-Band applications [1]. A microstrip aperture-coupled dielectric resonator element in the shape of a cross was designed as a feed element for a cylindrical cavity antenna. The analysis was performed using a Finite Difference Time Domain (FD-TD) method [2]. As part of the continuing development of this antenna, it is being modelled at higher frequencies using a Transmission-Line-Matrix (TLM) method detailed in [3]. The TLM method is a differential-equation based numerical analysis technique, which is capable of determining approximate solutions of the time-dependent Maxwell's equations in the presence of complex environments. It is especially suited to the non-planar, non-homogeneous aperture-fed geometry of the antenna under consideration. This paper presents the results obtained from the TLM simulation of the aperture-fed dielectric cross, both as an individual element and as the feed element for the cylindrical cavity. Theoretical results are compared to the experimental results for the complete cavity geometry. This theoretical approach allows for optimization of the antenna element without the necessity of performing several measurements.