CIRCULAR RING SHAPED POLARIZATION RECONFIGURABLE ANTENNA FOR WIRELESS COMMUNICATIONS

A single fed polarization reconfigurable antenna is presented. The antenna comprises of a circular ring-shaped radiating element along with reconfigurable feed network located at its center which eliminates the need for additional space for reconfigurable feed network. A separate biasing network is placed to bias the pin diodes in the feed network for polarization reconfiguration and achieves three polarization states (linear, left-hand and right-hand circularly polarization). The antenna is designed to operate at 2.4 GHz ISM band. The antenna parameters are simulated using Ansoft highfrequency structure simulator and are validated using Agilent network analyzer (N9925A) and antenna test systems. The antenna achieves a good −10 dB impedance bandwidth of 85 MHz (2.40–2.485) GHz in linear state and 85 MHz (2.41–2.495) GHz in the circularly polarization states along with better crosspolarization isolation (≥ 15 dB) in the operating bands and hence more suitable for modern wireless communications.