Efficient implementation of the spectral domain method including precalculated corner basis functions

A general implementation of the Spectral Domain Method, formulated for planar microstrip circuits of arbitrary metallisation pattern is presented. The inclusion of a priori knowledge of the edge and corner singularities in the set of basis functions results in a large decrease In the order of the problem to be solved. Libraries of basis functions allow the rapid rigorous analysis of realistically complex circuits. Calculated S-parameters are given for three microstrip lowpass filters and compared to results from both measured data and other techniques