大型星载Ku波段波导缝隙阵列天线 ——宽频带设计及热变形分析

高度计波导缝隙阵列天线是高增益、低副瓣天线子系统, 其宽频带、窄波 束等特点对天线设计将提出较高要求. 天线阵面较大, 在空间环境冷热交替 的作用下会发生形变, 因此, 有必要研究形变对天线电性能的影响. 本文采 用天线阵分区馈电、波导中心馈电以及加载元件等技术, 解决了天线宽频带 设计问题, 并针对热变形问题, 提出一种分析天线热变形对其电性能影响的 新方法. 现已加工出8×10阵列天线实验件, 实测结果表明, 1.3以下 驻波带宽为340MHz, E面副瓣电平为-25.9dB, H面副瓣电平 为-27.2dB, 满足实际要求, 验证了设计方法的有效性. 

Wideband Design and Thermal Deformation Analysis of Space-borne Large Waveguide Slots Array Antenna in Ku-band

Waveguide slots array antenna was adopted in engineering project. Though this antenna had high gain, low side lobe etc, wideband requirement was a big challenge for it. As working in the space environment, large space-borne antenna would be influenced by the thermal deformation. It was necessary to analyze the influence on electrical performance, such as radiation pattern. In order to enlarge the band, antenna was separated into four areas to feed, and the feeding point was in the center of the waveguide. Special loads were exerted in waveguide H-T and E-T junctions to meet impedance matching. An approximate computation method was provided to analyze the influence of the thermal deformation on antenna performance. Some 8×10 slots array antennas were manufactured as the first step, and these antennas were tested in our near field testing system. The bandwidth of the Voltage Standing Wave Ratio (VSWR) below 1.3 was 340MHz, and the side lobe level was -25.9dB in E plane and -27.2dB in H plane. Measurement result indicated the availability of the designe.