Analysis of microstrip structures in multilayered substrates

This paper presents an efficient technique for a full-wave analysis of microstrip antennas, circuits and discontinuities. The proposed method solves an electric field integral equation with mixed potentials and includes radiation and surface wave effects. Of paramount relevance is the accurate determination of dyadic Green's functions corresponding to the microstrip flat multilayered substrate. The integral equation is numerically solved with a method of moments featuring either subsectional or entire domain basis functions. Finally, a simple multiport analysis combined with a numerical de-embedding process allows the evaluation of equivalent circuits and/or scattering matrices independent of the excitation model used.