Reflector antenna analysis method using Poynting vector tracing between virtual apertures

In this study, a highly efficient calculation method for analysing electrically large reflector antennas is presented. This method utilises fast Fourier transform enhanced direct integration to calculate beam propagation between parallel virtual apertures, and a novel Poynting vector tracing technique is introduced to treat wave reflections by arbitrary curved surface. Two virtual apertures are set perpendicular to the incident and reflected optical paths. As the centres of the virtual aperture planes coincide with the reflector surface, it makes the ray-tracing paths between the virtual apertures along with the reflector as short as possible. Owing to these innovative treatments, this method offers a high calculation accuracy comparable with classic physical optics (PO), but with much higher efficiency. By performing numerical comparisons with method of moments, PO algorithm implemented with commercial software FEKO and general reflector antenna software package, the advantages of the proposed method are presented in this study. The method proves to be applicable for the analysis of electrically large reflector antennas.