小型圆极化天线的交叉极化抑制方法研究  

Methods of Suppressing Cross Polarisation for a Miniaturised Circularly Polarised Antenna

作　　者：罗艺 柳志荣 LUO Yi;LIU Zhi-rong(The 10th Research Institute of China Electronics Technology Group Corporation,Chengdu,Sichuan610036,China;Shaanxi Lanying Aviation Electric Co.,Ltd.,Xi'an,Shaanxi710000,China)

机构地区：[1]中国电子科技集团公司第十研究所,四川成都610036 [2]陕西蓝鹰航空电器有限公司,陕西西安710000

出　　处：《电子学报》2021年第12期2490-2496,共7页Acta Electronica Sinica

摘　　要：本文研究了一种小型圆极化微带天线在低仰角下抑制交叉极化的方法.文中提出了在辐射贴片上设置一个交叉槽来缩小天线尺寸,其高度和直径的仅为0.123倍波长和0.777倍波长.进一步针对该天线,分析了天线在不同底板类型下的低仰角交叉极化特性,提出了一种紧凑的弯折线环腔底板结构.采用紧凑的MLRC(Meander-Line Ring Cavity)结构可以显著降低天线在低仰角下的交叉极化,并且在整个上半空间的轴比(AR,Axial Ratio)也得到改善.所获得的腔体高度和直径仅为0.064倍波长和0.448倍波长.天线电压驻波比(VSWR,Voltage Standing Wave Ratio)小于2的阻抗带宽达到20.8%,轴比小于3dB的圆极化带宽为8.5%.从天顶到水平面,交叉极化电平不大于23.2dB.轴比小于3dB时,波束宽度可达190°以上.A method of suppressing the cross polarisation of a miniaturised circularly polarised(CP)microstrip anten⁃na at low elevation angle is studied.A crossed slot on the radiation patch is utilised to miniaturise the proposed antenna,the antenna height is 0.777 times the wavelength,and the antenna diameter is 0.123 times the wavelength.Furthermore,the cross polarisation of the antenna at low elevation angle is analysed with different ground types,and a compact meander-line ring cavity(MLRC)ground is proposed.The cross polarisation at low elevation angle can be reduced significantly for the an⁃tenna with a compact MLRC,and the axial ratio(AR)is also improved in the whole upper-half space.The achieved height and diameter of the cavity are just 0.064 times the wavelength and 0.448 times the wavelength.The impedance bandwidth for voltage standingwave ratio(VSWR)less than 2 is 20.8%,and the CP bandwidth for AR less than 3dB is 8.5%.From the zenith to the horizontal,the cross-polarised levels are not greater than 23.2dB.The beamwidth for AR less than 3dB reaches more than 190°.

关 键 词：圆极化 天线 交叉极化 弯折线环腔 低仰角 圆极化带宽 

分 类 号：TN82[电子电信—信息与通信工程]