Polarization switchable flat antenna for WLAN applications

Abstract

Polarization switchable flat antenna for WLAN applications operated at the center frequency of 2.45 GHz. The proposed antenna consists of the square flat structure, three switches (six P-I-N diodes), transmission-line phase shifters of 0 and 90 degrees. The antenna can be switched between 5 different states: vertical, horizontal and slant polarizations for linear polarization (LP), left-handed circular polarization (LHCP) and right-handed circular polarization (RHCP) by controlling the DC bias of 5 V and the current of 16 mA for the P-I-N diodes. The simulated and measured results show that the proposed antenna can cover the impedance bandwidth from 2.400 GHz to 2.484 GHz and good axial ratio for the circular polarization.