宽频带低轴比双圆极化波导阵列天线设计

Design of a Dual Circular Polarization Waveguide Antenna Array with Wide Band and Low Axial Ratio

基于波导损耗小、易加工等特点,设计了一种应用于卫星通信系统的新型X波段宽频带低轴比双圆极化波导阵列天线。采用平面方形喇叭阵列、正交模耦合器和波导窄边耦合功分器来实现双圆极化的工作方式。据此设计,加工了一套16×16单元天线阵列,尺寸大小为440mm×440mm×50mm。采用电磁仿真软件Ansoft HFSS进行仿真设计,详细介绍了该天线的设计方法,测试结果和仿真结果吻合良好。测试结果表明,该天线在12%的工作频段内轴比优于1.5dB,驻波比优于1.6,带内增益大于31.0dB,天线辐射效率优于80%。

Considering the small loss and easy fabrication of waveguide, a novel dual circular polarization waveguide antenna array with wide band and low axial ratio is presented at X-band for satellite communications. Planar horn array is used to attain dual circular-polarization working with orthomode and rectangular side wall coupler. A demo array of 16×16 elements is designed, manufactured and tested. This antenna is low-profile and modular with dimensions of 440 mm × 440 mm × 50 ram. The antenna is simulated and designed by Ansoft HFSS. The complete design of the antenna is shown, and the measurements are compared with simulations to reveal very good agreement. The experimental results show that the axial ratio is less than l. 5 dB and the VSWR is less than 1.6 in the operation frequency band.