A model for describing mutual coupling in uniform circular arrays and its application to DOA estimation

A rigorous circuit model with a limited number of parameters is presented to describe mutual coupling in uniform circular arrays. The model, which is based on a phase-mode expansion, provides physical insight into the frequency dependence and the dependence on azimuth angle of the coupling between antenna elements. The derived circuit elements are used to develop dedicated techniques for direction-of-arrival (DOA) estimation in such arrays.