基于超材料馈电网络的全向双极化天线阵设计

Design of omnidirectional dual polarization antenna array based on metamaterial feed network

为了减小对天线阵辐射特性的影响,提出并设计了一种平行平板传输线结构的超材料串联馈电网络,基于超材料传输线设计了零相移传输线,利用零相移传输线设计了串联馈电网络.基于该馈电网络设计了一种全向水平/垂直双极化4元天线阵.天线阵由4个全向双极化天线单元和2个超材料串联馈电网络组成.全向双极化天线单元由折顶偶极子天线和缝隙电容加载的零相移圆环天线构成.利用HFSS仿真软件对该天馈系统进行了仿真,结果表明,该天线阵的中心工作频率为3.5GHz,最大增益为7dB,交叉极化电平小于-35dB,隔离度大于40dB,不圆度小于±1.2dB,满足5G通信对基站天线和多入多出天线的要求.

To alleviate the influence on antenna array by radiation, a metamaterial serial feed network with parallel plate transmission line structure was proposed and designed. A zero-degree phase-shifting transmission line was designed based on the metamaterial transmission line, where the serial feed network was designed. Based upon the feed network, an omnidirectional horizontal/ vertical dual-polarized 4-element antenna array was designed. The antenna array is consisted of four omnidirectional dual- polarized antenna elements and two metamaterial serial feed networks. An omnidirectional dual-polarized antenna element is composed by a folding dipole antenna and a zero-degree phase-shifting loop antenna loaded with capacitance gaps. The antenna array and its feed networks were simulated by HFSS software. The results show that the central operating frequency of the antenna array is at 3. 5 GHz with the maximum gain of 7 dB. The cross-polarization level is less than -35 dB. The isolation is higher than 40 dB. And the out-of-roundness is less than ±1.2 dB, which meets the requirements of base station antenna and multiple input multiple output antenna for 5G communication.