Comparison of measured and calculated mutual coupling in the near field between microwave antennas

Measurements of near-field mutual coupling were performed between two moderate sized microwave antennas and compared to coupling calculated using recently developed computer programs. Input data for the programs are the complex far-field radiation patterns of the antennas. Experimentally determined and calculated coupling as a function of both transverse displacement and separation agree closely except for a constant offset observed in some cases. In addition, coupling values computed using a program which approximates the ar-field radiation patterns were compared to experiment and found to be satisfactory.