Design of dual-band circularly polarized dielectric resonator antenna using a higher-order mode

A singly-fed dual-band circularly polarized dielectric resonator antenna (DRA) is investigated in this paper. It makes use of the fundamental TE₁₁₁mode and higher-order TE₁₁₃mode of a rectangular DRA for the dualband design. The DRA has a square cross section. It is excited by a single microstripline-fed rectangular slot fed. To generate circularly polarized (CP) fields, two corners of the DRA are truncated at 45°, exciting two sets of degenerate orthogonal modes, namely (TE₁₁₁^x, TE₁₁₁^y) and (TE₁₁₃^x, TE₁₁₃^y). Measured results show that the axial-ratio bandwidths of the lower and upper bands are 5.2% and 1.4%, respectively. The reflection coefficient, axial ratio, radiation pattern, and gain of the antenna are studied using ANSYS HFSS. Measurements were carried out to verify the simulations and reasonable agreement between the measured and simulated results is observed.