Dual-band circularly polarized slot antenna for WiMAX/WLAN application

A new antenna with dual-band circular polarization for the reception of WiMAX and WLAN is presented in this article. The circular polarization is achieved by a symmetrical U-slot together with an L-slot. The width of the signal strip is narrowed at the end of the feed point to widen the 3-dB axial ratio (AR) bandwidth and create a good impedance matching for the proposed antenna. A parametric study is conducted using a commercial simulation software based on the method of moments, and the antenna prototype is constructed and measured for providing the simulation validation. Experimental results show that the measured AR bandwidths are about 16.6% and 16.2% with respect to the center frequency at 3.5GHz and 5.3GHz. The radiation characteristics of the proposed antenna are also presented.