Single Feed Dual-band Circularly Polarized Modified Shape Square Dielectric Resonator Antenna for WiMAX and WLAN Applications

In this paper, a dual-band circularly polarized (CP) modified shape square dielectric resonator antenna (SDRA) for WiMAX (Wireless Interoperability for Microwave Access) and WLAN (Wireless Local Area Network) applications is proposed. The proposed SDRA is fed diagonally using a single coaxial probe. The dual-band CP is achieved by introducing a pair of rectangular grooves on the SDRA faces along the YZ plane and a pair of rectangular ridges on the SDRA faces along the XZ plane. The pair of rectangular grooves and ridges are placed in offset position to achieve better CP performance and wide impedance bandwidth. The proposed SDRA provides an impedance bandwidth of 30.14% (3.1 GHz to 4.2 GHz) and 8.16% (4.7 GHz to 5.1 GHz) with the 3 dB axial ratio bandwidth (ARBW) of 5.88% (3.3) GHz to 3.5 GHz) and 4% (4.9 GHz to 5.1 GHz) in the lower and upper frequency bands respectively. The proposed SDRA exhibits a peak gain of 6.3 dBi and 5.2 dBi in the lower and upper frequency bands respectively.