Design of Fermat-Archimedes spiral dual-via EBG structure for low mutual coupling antenna array

In this paper, Fermat-Archimedes spiral dual-via EBG structure is designed and applied into antenna array. By combining Fermat slot line with Archimedes spiral slot line, the size of rectangle EBG cell is reduced. Mutual coupling of 2-element antenna array is simulated. Effect of EBG structure on mutual coupling is investigated. Furthermore, a 4-element antenna array with the proposed EBG structure is fabricated and measured. It is found that the mutual coupling between antenna elements can be reduced effectively by the Fermat-Archimedes spiral dual-via EBG structure.