Bi-Directional EBG for 4 × 4 Longitudinal and Lateral Mutual Coupling Reduction in MIMO Antennas for 5.8 GHz Applications

Abstract

This paper presents the process of reducing the mutual coupling in both longitudinal and lateral directions of 2 × 2 (MIMO) antenna systems for 5.8 GHz applications. For size reduction, a bilateral EM band gap structure is added to the ground which helps in reducing the edge-to-edge distance between neighboring antennas rather than placing it between antenna elements. The results from Electromagnetic simulation and experimental measurements are discussed. A comparison between the use of the bilateral EBG between antenna elements to the non-using of any of the cases. For longitudinal isolation, the spacing between two opposite elements is 0.07 λ0 and 11 dB isolation was achieved. For lateral isolation, the spacing between two elements is 0.5 λ0 and 8 dB isolation was achieved. A measured isolation improvement is 10 dB for longitudinal isolation and 15 dB for lateral isolation.