基于高输入阻抗偶极子的低剖面宽带双极化基站天线

A Low Profile, Wideband and Dual-Polarized Base Station AntennaBased on the Dipole with High Input Impedance

本文提出了一种低剖面的宽带双极化基站天线.该天线由两个相互交叉的扇形偶极子演变而来.首先,在扇形偶极子末端增加环形窄微带和金属化通孔,使天线端口输入阻抗增大,达到降低天线高度的目的 .然后,增大扇形偶极子臂的张角,产生第二谐振点,提高天线带宽.该双极化天线工作在2.17~2.7 GHz频段,可提供22%的带宽.而且,由于两个偶极子围绕几何中心高度对称,该天线在工作频带内可以获得较高的隔离度和交叉极化鉴别度,其中隔离度仿真值可达51 dB,0°交叉极化鉴别度仿真值可达48 dB.该天线的峰值增益仿真值高达9.6 dBi.综上所述,该天线具有高隔离、高交叉极化鉴别度和高增益等优点,在基站系统中具有良好的应用前景.

In this paper,a wideband,dual-polarized antenna with extremely low profile is developed for base station application.The antenna evolved from two fan-shaped dipoles that crossed each other.By adding annular branches and met⁃allized through holes at the end of the dipole,its port input impedance increases when the antenna occupies a lower height.Besides,the flare angle of the fan-shaped arm is increased so that a second resonant point can be generated to achieve the purpose of expanding the bandwidth.The dual-polarized antenna can provide a bandwidth of 22%in the 2.17~2.7 GHz band.Because the two dipoles is highly symmetrical about the geometric center,the isolation degree and cross polarization discrimination are high in the working frequency band,among which the simulation value of the isolation degree can reach 51 dB,and the simulation value of the cross polarization discrimination in the 0°can reach 48 dB.In addition,the simulated peak gain of the antenna is as high as 9.6 dBi.The antenna has the advantages of high isolation,high cross-polarization dis⁃crimination and high gain,and has a good application prospect in the base station system.