Radiation pattern calculation of flanged reflector antennas

A technique for calculating radiation patterns of reflector antennas with curvilinear impedance peripheral flanges is presented. It is based on the uniform asymptotic theory with numerical diffraction coefficients and on the equivalent edge currents method. The use of numerical diffraction coefficients allows to account near-field terms in the incident field and nonuniform impedance distributions on the flange, provided that dimensions of the flange do not exceed several wavelengths.