On the theory of the electromagnetic wave propagation through inhomogeneous dispersive media

A new approach and corresponding method are presented which can be of use in resolving the problem of determination of the eigen frequencies for confined systems, such as resonators, wave guides, and the like, filled with a temporally and spatially dispersive medium. The problem of excitation of such systems by external current is considered. The theory of local and small perturbations as applied to those systems, is presented.