The spectral domain-exponential matrix method is developed to evaluate the full-wave dyadic Green's function for generalized anisotropic substrate-superstrate structures. The method of moments is employed to obtain the basic dispersive characteristics of microstrip and inverted microstrip circuit elements on such structures. A collection of results are presented for the propagation constant and characteristic impedance of microstrip elements on generalized anisotropic layers. Emphasis will be placed on the investigation of microstrip properties on a biased ferrite-semiconductor interface. The modeling accounts for arbitrarily-oriented dc bias magnetic fields. The phenomenon of forward and backward wave propagation on this type of nonreciprocal structure will be highlighted.