Characterization of planar passive circuits using source method

A source method is developed for analysing STEP and GAP discontinuities in microstrip circuits. We propose to model the circuit by a rigorous method. including sources and using roof top trial functions. The roof top expansion functions approach is largely developed in the literature for complex discontinuities. Nevertheless, this approach generates a large matrix system. The numerical results obtained, giving the transmission coefficients for the STEP and GAP discontinuities, are compared with previously published data.