Dual-grid BoR-FDTD technique applied for prime feed antenna study

This paper presents some studies on prime feed reflector antennas system using the dual-grid BoR-FDTD approach. The technique requires two consecutive simulation steps, where the stored data from the first simulation can be repeatedly used in the second simulation domain. This offers fast parametric study involving the feed structure to study its effect on overall antenna performance. Based on this study, antenna gain could drop by more than 1 dB if the feed position shifted > 0.5λ₀ from the reflector´s focal point. The blockage due to feed structure does not significantly affect the radiation pattern performance for parabolic reflector system. However, for spherical reflector, the blockage effect is much notable.