Reduction of Mutual Coupling in UWB-MIMO Antennas by Using EBG Structures based on A T-shaped Ground Branch

A novel decoupling structure is proposed for ultrawideband (UWB) MIMO antennas. It can improve isolation between two element antennas by using electromagnetic band gap (EBG) structures based on a T-shaped ground branch. The proposed antenna has a good impedance matching, 2.2 to 12GHz and compact size, 50mm×35mm×1.6mm. there is a good isolation of the proposed antenna, below -20dB in the whole operation band, and a low envelop correlation ( ). A T-shaped ground branch is used to increase the isolation in the middle and low frequency band and a mushroom type EBG structure is introduced to achieve good isolation in the high frequency range. The simulation results of the proposed antenna are calculated by High-Frequency Structure Simulator (HFSS) and the proposed antenna be applied in UWB-MIMO system.