宽频带±45°双极化基站天线的设计

Design of Broadband ± 45° Dual-Polarized Base Stations Antenna

本文设计了应用于2G,3G,4G(LTE)的一种宽频带±45°双极化基站天线.天线由两组垂直交叉的蝴蝶结状偶极子天线构成,每一组偶极子天线通过连接同轴线的短截线馈电,从而实现了天线的平面结构.通过在每组交叉偶极子天线上开设3个矩形缝隙和1个V形缝隙,可以有效地拓宽设计天线的阻抗带宽、改善天线的增益.仿真结果表明:该天线可以工作在1.7~2.7GHz频率范围内,两端口的回波损耗大于15dB,两端口之间隔离度大于27dB,半功率波束宽度在65°±3°范围内,整个频段内增益均大于7.7dBi,前后向增益比大于20dB.

In this paper,a broadband ±45°dual-polarized antenna is proposed for 2 G/3 G/4 G（LTE）base stations.The dual-polarized antenna is composed of two perpendicularly crossed bow-tie dipoles.Each bow-tie dipole is excited by a microstrip stub that is connected with a coaxial line.So,a full planar dual polarized antenna is implemented.By setting three rectangular gaps and a V-shaped gap on each cross-dipole antenna,the impedance bandwidth can be widened and the gain can be improved effectively.The simulation results show that the proposed dual-polarized antenna has a bandwidth of 45%（1.7~2.7 GHz）for return loss15 dB with an isolation higher than 27 dB between two polarized input ports.The dual-polarized antenna has a half-power beam width（HPBW）of around 65°±3°,an average gain of7.7 dBi over operating frequencies,and a forward and backward gain ratio of greater than 20 dB.