An efficient computation of the electromagnetic mutual coupling between two aperture antennas

The problem of the numerical evaluation of the coupling among the electromagnetic fields generated by two-aperture antennas is considered. The theoretical method used is based on plane-wave scattering theory, leading to a very efficient formula of the evaluation of the electromagnetic coupling coefficient. Results of a computer simulation are presented for the case of two rectangular/circular aperture antennas working in the X-band. Numerical computations have been performed by neglecting the evanescent part of the plane-wave spectrum. This assumption and the corresponding numerical evaluations are observed to be consistent with the results found in the literature