Efficient Body of Revolution Method of Moments for rotationally symmetric antenna systems with offset illumination

An efficient Body of Revolution Method of Moments formulation is presented in which the unknown surface current density on the generatrix of the rotationally symmetric scatterer is expanded in terms of higher-order hierarchical Legendre basis functions. Careful attention has been paid to fast evaluation of the involved modal Green´s functions. The efficient formulation is particularly useful for the analysis of rotationally symmetric scatterers illuminated by an offset feed for which a method of moments problem must be solved for a large number of azimuthal modes.