An experimental study on reduction of mutual coupling between closely placed MSAs using wave absorber

In this paper, reduction of mutual coupling between microstrip antennas using wave absorber is presented. The two radiation patches are closely placed and the absorber is arranged in between to reduce the mutual coupling. The size appropriate for reducing the mutual coupling was studied analytically. From these results, the size of the absorber was determined as 12×12 mm. The measured mutual coupling was as low as 10 dB compared with the simulated ones. It was assumed that the difference is caused by a gap between the absorber and the substrate. Then the simulated results with the gap agreed well with the measured ones.