Rapidly converging spectral-domain analysis of rectangularly shielded layered microstrip lines

A moment-method-oriented direct integral-equation technique is presented for the exact analysis of rectangularly shielded layered microstrip lines. This technique retains the simplicity of conventional moment methods while optimizing them by recasting all matrix elements into rapidly converging series. Filling up the matrix requires no numerical integration. The proposed algorithms yield highly accurate results both for the modal currents and propagation constants.