Wide Bandwidth Microstrip Patch Antenna with Improved Cross-polarization

A new method to decrease cross-polarization of the wide-bandwidth microstrip patch antenna (MPA) is proposed in this paper. Firstly, a pair of shorting walls are installed at the non-radiation edges of the MPA, which can eliminate the asymmetry of H-plane radiation electric field caused by the asymmetry of feeding port, thereby suppressing H-plane cross-polarization. Secondly, the bandwidth of the MPA is widened by cutting a square-ring slot near the feeding port. Thirdly, in order to improve the cross-polarization level of the antenna in the diagonal plane (D-plane), the radiator is rotated at an angle. Finally, our proposed MPA is simulated and verified. The results show that the proposed antenna achieved enhanced bandwidth of more than 28%, and the cross-polarizations of the E-plane, H-plane, and D-plane are kept of less than −10 dB.