A Compact, Low-Profile, Wideband, Electrically Controlled, Tri-Polarization-Reconfigurable Antenna With Quadruple Gap-Coupled Patches

This communication presents a compact, low-profile, wideband, polarization-reconfigurable antenna with right-handed circular polarization (RHCP), left-handed circular polarization (LHCP), and linear polarization (LP) diversity. The antenna consisting of quadruple identical gap-coupled square patches possesses dual wideband degenerate modes, which could be properly allocated by controlling ON/OFF states of four p-i-n diodes integrated into an overlying specially engineered driven element to dynamically produce RHCP, LHCP, and LP radiations. Due to the collaboration between the gap-coupled patches and such a reconfigurable driven element, the proposed design could operate in a wide overlapped bandwidth of 7.1% in the three dynamical states while keeping a compact size of 0.56λ0× 0.56λ0and a low profile of 0.037λ0. Benefiting from the advantages of low profile, compact size, and wideband operation in three polarization-reconfigurable states, the proposed antenna is quite suitable for space-limited, wideband, intelligent, and anti-interference wireless systems.