Suppression of Mutual Coupling in Dual Differentially Fed Microstrip Patch Array Antenna

In this paper, mutual coupling suppression in a dual differentially fed microstrip patch antenna array with polarization diversity is studied. The investigated antenna is an array of two square patches and each patch is fed with two differential pairs to generate multiple polarization. A metamaterial absorbing wall is placed between the patches to isolate the patches in both E and H planes. The absorber wall comprises of an array of split ring resonators (SRR) printed within a dielectric substrate to decouple the patches. The introduction of the absorber wall results in an isolation enhancement of 15 dB and 5 dB in the E and H-planes respectively over a frequency bandwidth of 9.33-9.45 GHz.