MIMO Antenna Array Decoupling Based on a Metamaterial Structure

A metamaterial decoupling structure is designed and used to enhance the isolations in the MIMO antenna array consisting of two patch antenna elements which operate at 5.3 GHz. The distance from edge to edge between the two microstrip patch antennas is 11 mm which is about 0.19λ corresponding to the center resonance frequency. The designed metamaterial structure constructed with three modified split-resonator rings is periodically set in the middle of the devised MIMO array so as to reduce the effect of the surface wave propagation between the two microstrip antennas. The simulation results obtained from the calculations show that the isolation is enhanced about 12.5 dB without sacrificing the bandwidth and good radiation pattern characteristics.