MULTIFREQUENCY ELECTROMAGNETIC SCATTERING FROM INHOMOGENEOUS RECTANGULAR WAVE-GUIDES USING SHIFTED FREQUENCY INTERNAL EQUIVALENCE

Concept of shifted frequency internal equivalence (SFIE) for electroma gnetic scattering problems involving homogeneous or inhomogeneous bodi es is explained and applied to multi-frequency electromagnetic scatter ing from inhomogeneous dielectric and/or magnetic rectangular waveguid es. As is well known, surface integral formulation is only applicable to homogeneous structures, and in volume integral formulation it is ne cessary to repeat the solution process by generating data at each inci dent field frequency. Here it is shown that, volume interaction part o f the data generated only at a single frequency may be utilized at oth er frequencies in a wide frequency band while applying SFIE. Upon comb ination with an external equivalence, the solution is readily obtained .