Compact S-Shaped EBG Structures for Reduction of Mutual Coupling

In this article, two new shapes of EBG structures are presented for reducing mutual coupling between patch antenna MIMO arrays. The first structure is contained an S-shape patch with a via at center of it and the second one is a multilayer structure that is based on the S-shape formation. The patch antennas are operating at 5.35 GHz, which is defined for wireless application. Here an array of 2×5 EBG structures is implemented to reduce mutual coupling to more than 13.5dB and 20.5 dB respectively for first and second structures. The total size of antenna is 36mm×68mm×1.6mm. All the simulations have been carried out with HFSS for full wave simulation. The surface current density is reduced dramatically more than 84% and 92% for first and second structures respectively. In addition the effect of the change in unit cells distance on mutual coupling are studied for the second structure. The results are compared with some previous researches.