Analytical Solutions of TD Scattering Fields from Parabolic Reflector Antenna Illuminated by Plane Waves and Gaussian Beams

摘要

The increasing interests in the use of ultra-wideband or short pulse antennas for the target identification and remote sensing applications have driven the efforts to obtain direct time domain (TD) solutions in the electromagnetic (EM) analysis. This paper develops an Analytic Analysis of Transient Scattering from a parabolic reflector antenna illuminated by an Incident Plane Wave and electromagnetic (EM) fields of a general astigmatic Gaussian Beam (GB) respectively. The time domain transient analysis of Time Domain Physical Optical (TDPO) for parabolic reflector antenna illuminated by plane wave and TDPO with analytic time transform (ATT) for parabolic reflector antenna illuminated by Gaussian Beam (GB) are presented. It is obtained by analytically inverting, in closed-form, the corresponding frequency-domain (FD) solution based on physical optics (PO) integral, and coincidently can be decomposed in terms of reflection and diffraction effects as usually described in high-frequency asymptotic solutions. The ATT allows complex formulations with complex time variations in TD, and is thus able to treat the complex propagation phases resulted from a GB illumination on the reflector.