Reduction of the mutual coupling between aperture coupled microstrip patch antennas using EBG structure

This paper presents a method for reducing surface wave coupling between aperture coupled microstrip antennas by the use of mushroom-like electromagnetic band-gap (EBG) structures. Dispersion diagram of the EBG structures was studied by the FDTD method before the EBG structures were combined with the antennas to reduce the mutual coupling. Convolution perfect matched layer (CPML) and periodic boundary conditions (PBCs) were used in the FDTD method for accurate and efficient computing purpose. Case study shows that 16.4dB reduction of the mutual coupling was achieved at the designed resonant frequency by virtue of only a row of EBG structures, and the average reduction in the working band of the antenna was 7.57 dB. Thus, the method can be considered as a potential solution for mutual coupling reduction in array application.