ANALYSIS OF GUIDED MODES IN MULTILAYER MULTICONDUCTOR STRUCTURES BY THE BOUNDARY INTEGRAL-RESONANT MODE EXPANSION METHOD/

This paper describes a new method for the analysis of modes propagatin g in shielded waveguides consisting of many dielectric and perfectly c onducting layers of different widths. The eigenvalue problem inherent to the mode determination is formulated subdividing the structure into layered elementary wave-guides (EWG's) and matching the fields genera ted in adjacent EWG's by unknown equivalent sources placed at the inte rfaces. The special representation of the EWG field, consisting of bou ndary integrals and mode expansions, leads to a linear matrix eigenval ue problem involving a limited number of variables. Thanks to this pec uliarity the method permits to determine many modes in short computing times. The method was implemented in a flexible and fully automatic c omputer code, whose reliability and efficiency has been confirmed by m any tests.