Dual-Port MIMO Antenna with Defected Ground Structure for UWB Wireless Applications

A dual-port multiple-input multiple-output miniaturized key-shaped antenna for ultra-wideband applications is presented. The proposed MIMO configuration has a compact size of 25 mm× 40mm× 0.8 mm with microstrip fed and a common ground plane. A rectangular strip of 1 mm× 14 mm with circular knob geometry and two concave grooves 4.40 mm × 3.75 mm are introduced in the ground plane to enhance the isolation and broaden the impedance bandwidth. The band-notched 4.5–18 GHz can be obtained by etching two stubs on radiating patch. Besides, the step formation and different MIMO configurations are analyzed. The simulated results show that the proposed MIMO geometry has a wide bandwidth ranging from 4–21 GHz with a mutual coupling of less than −16dB, and better radiation patterns. Further, it has an envelop correlation coefficient (ECC) of less than 0.02 and diversity gain of more than 9.95 dB as well as a good total active reflection coefficient value.