Reduction of Mutual Coupling between Cavity-Backed Slot Antenna Elements

Maintaining mutual coupling suppressing structure as simple as possible is becoming attractive in the electromagnetic and antenna community. A novel parasitic patch structure that can reduce mutual coupling between cavity-backed slot antenna elements is proposed and studied. The structure consists of only a simple rectangular patch inserted between the antenna elements, and it is therefore low cost and straightforward to fabricate. The proposed structure can not only suppress the surface-mode propagation and reduce mutual coupling between slot antennas, but also improve radiation patterns. The features include small occupied area and very simple structure.