基于孔径耦合的毫米波宽带圆极化阵列天线

A Millimeter Wave Wideband Circularly Polarized Antenna Based on Aperture-coupled

针对毫米波宽带圆极化阵列天线设计中轴比带宽和外形尺寸较难兼顾的问题,提出基于孔径耦合的毫米波宽带圆极化阵列天线。该天线使用基于孔径耦合的磁电偶极子宽带圆极化天线作为天线单元,天线单元由四个水平方向的贴片和四个垂直方向的金属通孔组成,通过引入额外的金属条连接对角位置的两个贴片同时将另一对贴片内角剪切,将圆极化带宽提升到20%以上。天线单元的馈电通过在末端短路的基片集成波导(SIW)宽边上开横向槽耦合实现。在此基础上利用SIW制作馈电网络,实现毫米波8×8高增益宽带圆极化阵列天线的设计。天线实测结果表明,该阵列天线能够在52.8~67.2 GHz实现VSWR<2(相对带宽为23.3%),3 dB轴比带宽达到20.2%,天线增益大于25.2 dBic,辐射效率超过71.5%,是一种较优的毫米波宽带圆极化阵列形式。

A circularly polarized(CP)aperture-coupled magneto-electric(ME)dipole antenna applied to millimeter wave was proposed in this paper.The CP ME-dipole antenna fed by a transverse slot etched on the broad wall of a section of shorted-end substrate integrated waveguide(SIW)was convenient to integrate into substrates.The whole structure was composed of four vertical metallic pins and four horizontal patches.The planar electric dipole was attributed to the two pairs of horizontal patches,while the magnetic dipole is realized by the aperture between the patches.In order to generate CP radiation,an additional metallic strip was introduced to connect two patch sections located at diagonal positions.Besides,the inner corners of the other pair of patch sections were cut partially.Based on the stable unidirectional radiation patterns of the antenna element,an 8×8 high-gain wideband planar antenna array was proposed for 60 GHz millimeter wave applications.The measured impedance bandwidth of the fabricated prototype was 23.3%for|S11|<-10 dB.Because of the wide AR bandwidth of the new antenna element,a wide AR bandwidth of 20.2%could be achieved by this array.Gain up to 25.2 dBic and good radiation efficiency of around 71.5%were also obtained due to the use of a full-corporate SIW feed network.