An ACS Fed Circularly Polarised Antenna for S Band Applications
This paper presents a polarization reconfigurable ACS fed circular patch antenna to operate in S band. The radius of the antenna is 35 mm. It is designed on a Rogers 5880 (TM) substrate. Two F-shape arms are cut through the ground plane and tilted by 10 degrees to improve return loss and impedance bandwidth. Asymmetric Coplanar Feeding technique is used. The antenna resonates at 2.5 GHz. Two PIN diodes are placed on the F-shape arms to induce polarization reconfiguration. LHCP and RHCP is obtained when the PIN diodes are kept in OFF and ON switching states, respectively. The impedance bandwidth obtained is 432.9 MHz Gain of 4.237 and4.251 dB is obtained for LHCP and RHCP, respectively. The 2.5 GHz band can be made applicable for MIMO Antennas, Wi-Fi, WLAN, BLUETOOTH, GPS and 5G.
Keywords-Polarization Reconfiguration, Circular Polarization, ACS, PIN Diodes, MIMO