A novel dual-band compact electromagnetic bandgap (EBG) structure and its application in multi-antennas

In this paper, a novel dual-band compact rabbet spiral EBG structure is proposed. Simulations and experiments have been performed. The results verify that the rabbet spiral EBG structure has two winning features of dual frequency bandgap and compactness. The period of the EBG lattice is only 0.038lambda_L and 0.073lambda_H at the desired dual stopbands. Moreover, this structure provides an additional degree of freedom to control the bandgap characteristics more easily. The EBG structure is then inserted between two antennas to reduce the mutual coupling. A 7.51 dB mutual coupling reduction is achieved at the lower resonant frequency and a 10.1 dB mutual coupling reduction is achieved at the higher resonant frequency. This EBG structure, with the advantage of dual-band and compactness, finds attractive applications in various wireless communication areas, such as multi-antennas and compact antenna