Mutual Coupling Reduction Using I-Shaped Microstrip Line and X-Shaped Slot

A novel decoupling structure composed of an I-shaped microstrip line and an X-shaped slot etched from the ground plane is proposed and applied to decouple the conventional antenna array at 5.25GHz, whose typical edge-to-edge distance is 10mm (0.175 λ₀). Results indicate that the structure has superior decoupling capability, achieving a maximum 34.2dB reduction of mutual coupling. With wider impedance bandwidth, high isolation and improved gain, the structure is potential in the application of multi-element array and communication system.