On the coupling between MS antennas

The mutual coupling between antennas in an array is discussed. The authors present a brief history of this problem, clarify a few definitions, and unify the various analysis techniques using a scattering matrix formulation. An analysis of the structure of the scattering matrix produces an elegant series of terms. First, the coupling is ignored; second, the N-port network is used to model the mutual coupling; and third, if the antenna is a minimum scattering antenna, multiple reflections can be accommodated and incorporated into the analysis of mutual coupling. Results illustrating the major points and the advantages of the scalar spherical mode theory over the induced EMF approach are also presented.<>