Reconfigurable Microstrip Patch Antenna with Switchable Polarization

Abstract

A reconfigurable microstrip patch antenna with switchable polarization is proposed in this paper. The proposed antenna consists of a nearly square patch as a radiator truncated at two corners, two small parasitic patches are connected at the corners by using PIN diodes. The impedance bandwidth and axial ratio bandwidth are enhanced by changing the shape of the truncated corners. Good impedance match (S11 < −10 dB) and axial ratio (AR < 3 dB) are achieved at the operating frequency (5.15 GHz). The measured results are well matched with the simulated results and validated the switching operation of the antenna in three polarization states, i.e. left-hand circular polarization, linear polarization, and right-hand circular polarization. The proposed antenna is also tested at high RF power and measured its performance. The proposed antennas are suitable for WI-FI and WLAN applications.