Reduction of the coupling between microstrip arrays antennas using High Impedance Surface (HIS) structures

Electromagnetic Band-gap (EBG) or High Impedance Surface (HIS) structures are becoming more and more utilized in the microstrip antennas and particularly to reduce the mutual coupling between the radiate elements or arrays antennas. In this paper, firstly, the band-gap feature of HIS Mushroom-like and Fork-like have been studied by CST Microwave Studio (MWS) for application at 10 GHz and radio altimeter at 4.3 GHz. Secondly, those HIS structures are integrated into an antenna arrays system to reduce the mutual coupling for both frequency domain. The investigation includes both E and H coupling directions. A drastically mutual coupling reduction is reached ∼ 31 dB at 10 GHz and ∼ 25 dB at 4.3 GHz.