Mutual coupling reduction between dual polarized microstrip patch antennas using compact spiral Artificial Magnetic Conductor

In this paper, we present a dual polarized microstrip antenna above an Artificial Magnetic Conductor (AMC). It is printed on a high permittivity substrate (ε_r=9.82). The AMC is used in order to reduce the mutual coupling between two radiating elements. Two experimental prototypes are realized in order to validate the analysis. First, the performances of a patch antenna above AMC are analyzed. The return loss is less than -15 dB at 1.62 GHz. The measured radiation pattern shows that the antenna has a broadside gain of 7 dB and a cross-polar level about -15 dB. Then, the mutual coupling between two antennas above AMC is studied. 3 dB enhancement of mutual coupling compared to the array without AMC is observed at the operating frequency 1.62 GHz in H plane configuration. A good agreement between measurements and simulations results is observed.