Note on excitation of the electromagnetic earth-crust waveguide

The power of the reciprocity theorem, in being able to generate solutions of a wide class of layered media problems from a single known formulation, is pointed out. Specifically, we start with the solution for the mutual coupling between two Hertzian electric dipoles that are located in the resistive waveguide channel in the earth´s crust. We then obtain useful modifications of these results to allow for other locations and orientations of the dipoles including the extensions to magnetic dipoles.