Polarization-Reconfigurable Multi-Antenna for High Mutual Coupling Reduction Using Backload Parasitic Structure

This paper introduces a polarization-reconfigurable antenna array with reduced mutual coupling achieved by incorporating a backloaded parasitic structure, which is an easily loaded design. The proposed antenna array achieves high isolation while switching among arbitrary linear polarizations (LPs), left-hand circular polarization (LHCP), and right-hand circular polarization (RHCP). The proposed method is simple, feasible and capable of achieving high isolation of over 30 dB of the mutual coupling at the operating frequency by adding a backloaded parasitic structure without the need to modify the parameters of original antenna. As a proof of concept, a 2 × 2 antenna array was designed, fabricated and measured to demonstrate the polarized-reconfigurable performance of the antenna and the effectiveness of the easy-loading structure to reduce the couplings.