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Accoppiamento modale nello spettro continuo per strutture guidanti / Daniele, Vito; Montrosset, Ivo; Zich, Rodolfo. - STAMPA. - unico:(1976), pp. 141-143. (Intervento presentato al convegno Radio Science, Volume 8, Number 1, pages 63-70, January 1973 Radiation by arbitrary sources in anisotropic stratified media V. G. Daniele and R. S. Zich Istituto di Elettronica e Telecommunicazioni, Politecnico di Torino, Torino, Italy (Received January 28, 1972; revised July 7, 1972.) The radiation of an arbitrary source in a stratified system including anisotropic slabs is considered. Starting from an abstract-operator formulation given by Bresler and Marcuvitz [1956, 1957], the transverse field is evaluated by using a Fourier-integral representation. The Green's function is expressed through the evaluation of the source-free solutions. The scattered field and the plane-wave response are examined. An example is given concerning the field radi- ated in the presence of an anisotropic ferrite slab. The far field is evaluated through a saddle- point integration. INTRODUCTION Electromagnetic problems require the evaluation of the electromagnetic field produced by prescribed sources in a given medium. The complexity of the problem depends essentially on the properties of the medium in which the field propagates. Practical problems are usually defined in nonhomogeneous regions. The medium may change its properties continuously (troposphere, ionosphere, particular lenses), or it may present surfaces of discontinuity (stratified media, guided waves, systems, and scat- terers). In both cases, the problems can be stated in terms of electromagnetic fields defined in the whole space and obeying the same system of Maxwell equations with coefficient functions of the point. A first step in approaching these problems is to consider media stratified perpendicularly to a fixed direction, with properties changing continuously or discontinuously. A fundamental contribution has been given by Marcuvitz and Schwinger [1951] by stating the problem in terms of the transverse field com- ponents, which are continuous on discontinuity sections and can be expanded in terms of z-inde- pendent transverse-vector eigen tenutosi a L'Aquila (I) nel 24-25 Giugno 1976).