A polarization reconfigurable antenna with continuously tunable linear polarization angle

In this paper, a reconfigurable antenna with continuously tunable linear polarization angles is designed. The linear polarization (LP) wave comes from the superposition of a pair of left-handed circular polarization (LHCP) wave and right-handed circular polarization (RHCP) wave with equal amplitude and out-of-phase. The rotation of the polarization angle of LP wave is controlled by the phase difference between the LHCP and RHCP waves. A reconfigurable phase-shift network based on quasi-reflection phase shifter and a switch circuit are designed to match the dual CP microstrip patch. Simulation results show that the LP angle can be continuously tunable from −96°to +96°. The antenna maintains a cross-polarization discrimination better than 18.8 dB and a stable pattern at 5 GHz various polarization angles.