A General Quadrature Formula For Efficient Evaluation Of Radiation Integrals

Abstract

An efficient and general numerical procedure for evaluating the Physical Optics integrals occurring in the analysis and design of reflector antennas is presented. ‘The procedure combines Ludwig’s integration technique (i.e., independent interpolation of the integrand amplitude and phase) with a predictorcorrector scheme. This combination eliminates the amplitude and phase ambiguities present in the real+imaginary algebra used in machine calculations. The performance of the procledure is investigated on a typical case study: the evaluation of the field scattered by an offset paraboloidal reflector.