Radiation Pattern Decoupling Method of E-Plane-Coupled Patch Antennas

RPD E-plane-coupled patch antennas are presented in this article with radiation pattern decoupling (RPD) characteristics. Two patch elements are placed side by side, forming a whole patch radiator. To decouple the patch antennas, TM20 and TM30 modes are excited simultaneously, and their resonant frequencies are merged together by L-shaped slots and metallic vias. The L-shaped slots can not only adjust the resonant frequencies of the TM20 and TM30 modes, they also provide slot mode. The metallic vias are placed in the interface of patches to tune that of the TM20 mode. To verify the presented idea, a prototype is designed, fabricated, and measured for 2.4-GHz WLAN band. Good agreement can be observed between the measured and simulated results. The measured overlapping 10-dB impedance bandwidth is 6.9% (2.35-2.52 GHz), with a port isolation level of higher than 20 dB. Undistorted and symmetrical radiation patterns can be highlighted, showing good RPD effect.