US Patent 7352328 Flat-plate MIMO array antenna with isolation element

A flat-plate MIMO array antenna includes a substrate, a plurality of antenna elements disposed on the substrate, and at least one isolation element interposed between a plurality of antenna elements on the substrate and connected to a ground. Mutual interference between the antenna elements is prevented by the isolation element formed between the antenna elements, thereby preventing the distortion of the radiation pattern. Also, since the isolation element is grounded to the ground surface, the isolation element operates as a parasitic antenna, thereby increasing the output gain.