Analysis of Omnidirectional Dual-Reflector Antenna and Feeding Horn Using Method of Moments

A hybrid numerical technique is applied for the analysis of circularly symmetric dual reflector antenna fed by TEM coaxial horn to generate an omnidirectional radiation pattern. By following the steps of a technique developed for the analysis of horn antennas, it employs a stepped-waveguide method to analyze the interior surfaces of the TEM coaxial horn transition and the electric field integral equation (EFIE) is applied on the outer surfaces of the TEM coaxial horn including the radiating aperture and the reflectors. Simultaneously, the magnetic field integral equation (MFIE) is employed on the aperture to relate the aperture fields and those in the horn transition. Method of moments (MoM) is employed to numerically solve the resultant hybrid field integral equation. The technique is applied for electromagnetic analysis of a coaxial TEM horn antenna and an omnidirectional dual reflector antenna. Results for the antenna return loss at the input port and for the vertical radiation pattern are given and compared with measurements and with commercial software results.