Wideband Antenna Arrays Based on a Circular Waveguide with the H01 Mode

Two variants of a cophased antenna array excited by the H-01 mode of a circular metal waveguide are proposed and analyzed. In the first and second variants, the array consists of 16 and 24 elements (open ends of a rectangular waveguide), respectively. Electrodynamic simulation and optimization of the antenna parameters are performed using the finite-element method and finite-difference method in the time domain. The simulated results show that the optimized first variant provides matching at a level of -15 dB in a band of 25.6-45 GHz, and the second variant provides matching in a band of 27-38 GHz. For both variants, the full efficiency is greater than 0.9 in a band of 26-38 GHz.