On the radiation of a surface source along the normal to the boundary of a half-space and a plane-layered structure

On the basis of the rigorous theory of radiation from an elementary current source located at the boundary of a plane-layered structure, the radiation of an arbitrary distribution of the surface current is considered. A strict relationship is obtained between the normal-radiated fields generated by an arbitrary distribution of the external surface current in the half-spaces surrounding the plane-layered structure. It is shown that the ratio of the amplitudes of electric fields at the same distance from a source emitting in opposite directions, normal to a plane-layered structure, is determined by a simple algebraic expression that includes the electromagnetic parameters of the media and the thickness of the structure's films. Special cases are also considered: a surface radiation source at the boundary of one homogeneous film and a surface source at the boundary of two homogeneous half-spaces.