Triangular-domain basis functions for full-wave analysis of microstrip discontinuities

A numerical technique for computing the S-parameters of arbitrarily shaped microstrip discontinuities and interconnects is presented. The microstrip conducting surface is rendered in a triangular discretization. Unknown currents are expanded with triangular-domain basis functions in a method of moments solution to the mixed-potential integral equation (MPIE). Triangular basis functions offer several advantages over rectangular subdomain functions, including their ability to conform readily to arbitrary geometries without a staircase effect. Examples comparing triangular-domain modeling with rectangular-domain modeling and experiment are given