Characterization and Reduction of Mutual Coupling Between Stacked Patches

A rigorous analysis of mutual coupling between stacked patches is proposed in this work. The considered stacked-patch configuration has a dielectric-air-dielectric topology, and the level of mutual coupling has been related to the working region, which is defined depending on the gain and frequency bandwidth of the antenna, as well as on the shape of the radiation pattern. For certain antenna parameters a dip appears in the mutual coupling characteristic, and detailed study of this phenomenon has been carried out. Since this dip in the mutual coupling depends on the resonant frequency of the parasitic patch, it can be used to reduce the mutual coupling in the operational frequency bandwidth of the antenna. We have developed an experimental model that has proven this concept of antenna coupling reduction. Finally, the influence of other antenna parameters on the mutual coupling level has been studied.