Design a Broadband Dual-Polarized Antenna

In this paper, a broadband dual-polarized antenna with operating frequency at 2.4 GHz for Wireless Local Area Network (WLAN) is presented. This antenna is a combination of left-handed circular polarized (LHCP) and right-handed circular polarized (RHCP). The proposed dual-polarized antenna is designed by using L-probe amendment with inverted rectangular patch. In order to perform with dual polarization by using single patch, the antenna is designed with two ports where both sides of the inverted rectangular patch is designed with one rectangular notch and two similar dimension circular notches. The inverted rectangular patch is separated with the ground plane by air gap layer to enhance the gain of the dual-polarized antenna. The simulation is done by using Computer Simulation Technology (CST) software. Based on the simulation result, port 1 and port 2 both achieved operating frequency at 2.4 GHz with return loss of -14.864 dB which the frequency range from 2.292 GHz to 2.501 GHz. Both ports obtained bandwidth of 209 MHz which meets broadband operation. Port 1 and port 2 both obtained gain of 7.343 dB with total efficiency -0.8251 dB. Furthermore, the minimum axial ratio for port 1 and port 2 are similar which is 0.342 dB with 3 dB axial ratio bandwidth of 620 MHz.