Mutual Coupling Reduction in Patch Antenna Arrays Using a UC-EBG Superstrate

TLDR

Reducing mutual coupling between antenna array elements is a key design challenge, and electromagnetic band‑gap (EBG) structures fabricated with microstrip technology offer an attractive mitigation approach. The study proposes a novel UC‑EBG configuration to simultaneously reduce element separation and mutual coupling, thereby enhancing patch‑antenna directivity. The approach places UC‑EBG structures atop the antenna layer to achieve the coupling reduction. The configuration successfully reduces coupling and element spacing while eliminating drawbacks noted in prior UC‑EBG designs.

Abstract

Reducing mutual coupling between elements of an antenna array is one of the main topics in array designs. The use of electromagnetic band-gap (EBG) structures built by microstrip technology is an attractive way to mitigate the mutual coupling problem. This letter describes a novel configuration of uniplanar compact electromagnetic band-gap (UC-EBG) structures to reduce mutual coupling between the radiating elements. The idea is to use the UC-EBG structures placed on top of the antenna layer. The main objective is to reduce both the element separation and the mutual coupling between the patch antennas, which in turn increases antenna directivity. The proposed configuration eliminates drawbacks of similar structures presented in previous works.