Calculation of antenna mutual coupling from radiated far fields

Mutual coupling between a pair of identical array elements is calculated from the radiated far field. The mutual coupling is found by using the reaction theorem applied to a single element. Different reaction surfaces are considered and results are compared to the conventional near and far field aperture surface integration technique. Results of the far field reaction technique are given for both a Hertzian dipole and waveguide aperture model. The results clearly show increased accuracy when compared with conventional aperture surface calculations using far fields. The method is believed to provide a quick and easy estimate of the mutual coupling from the measured far field data of a single array element. The technique is intended to be used as a development tool for the design of phased array elements with low mutual coupling