I. Introduction
In recent years, there has been a tremendous increase in research being carried out on beam forming arrayed antennas, particularly for communication and radar system applications. Retrodirective antennas, also known as self-phasing arrays, appear to be attractive solutions for some of these applications. A retrodirective antenna is an arrayed antenna that transmits in the direction of the incoming electromagnetic signal without a priori knowledge of the incoming signal's direction.