A novel passive feeding network for isolation enhancement of dual-polarized antenna

A novel passive feeding network is proposed to achieve isolation enhancement for the dual-polarized antenna in this paper. The proposed feeding network is composed of two 50 ohm transmission lines, a rectangular loop with an open-ended and another two short-circuited transmission lines. Compared with the antenna without this feeding network, the simulated results show that the isolation improvement of the antenna with the feeding network can be improved by at least 14.7dB or at most 18.3dB over the frequency band of 2.5-2.7GHz. More importantly, the dual-polarized antenna keeps other good performance such as VSWR<;1.5 and stable radiation pattern, while the feeding network is loaded. The proposed feeding network is easy to integrated with antenna or antenna array.