Electromagnetic Coupling Reduction in Microstrip Antenna Arrays Using Single-Negative Electric Waveguided Metamaterials

A single-negative electric waveguided metamaterial (WG-MTM) is proposed using folded complementary split single ring resonator (FCSSRR) to reduce mutual coupling in antenna arrays for MIMO applications. The WG-MTM is investigated numerically, which proved to exhibit electric resonance and band-gap property. Two antenna arrays have been designed, fabricated and measured. By inserting the electric negative metamaterial, a mutual coupling reduction of 9.2dB has been achieved with an edge-to-edge distance less than 0.17 (where is the operating wavelength). Moreover, the metamaterial loaded antenna has better far-field radiation patterns compared with the reference antenna. Thus, this novel structure not only has good coupling reduction ability, but also can optimize the performances of the antennas.