一种星载天线金属网PIM性能的波导测试方法

A waveguide test method for Passive Intermodulation performance of spaceborne antenna metal mesh

摘要:

金属网的无源互调(PIM)是大功率星载网状天线的一项重要性能参数。传统的金属网无源互调测试主要采用空间辐射法，但空间辐射法需要的金属网样件尺寸大，测试效率低。对此，提出一种基于三端口模块波导测试系统的金属网无源互调性能测试方法。为验证测试方法的有效性，搭建了基于三端口模块的金属网PIM性能测试系统，并对传统型和改进型2个金属网样件进行了PIM性能测试。测试结果表明，改进后的金属网PIM性能提升了50 dB以上。本文提出的金属网PIM性能测试方法使用的三端口测试系统集成度高，性能稳定，系统搭建效率高。相比传统的空间辐射测试法，本文方法的测试样件尺寸减小了一个数量级，为快速研究新型低PIM金属网提供了有力支持。

Abstract:

The Passive Intermodulation(PIM) value of the reflector's metal mesh, an important performance parameter of high-power spaceborne mesh antenna, is tested traditionally by the radiation method which requires a large size of metal mesh sample and has a low test efficiency. A 3-port PIM test method is proposed for the metal mesh, which is carried out by adopting a waveguide testing system based on the 3-port module. A PIM performance test system based on the 3-port module is constructed in order to verify the effectiveness of this test method. The PIM performance test is carried out on two metal mesh samples of the traditional type and the improved type, respectively. The test results show that the PIM performance of the improved metal mesh sample has been improved by 50 dB than that of the traditional mesh sample. This metal mesh's PIM test system bears the characteristics of high integration, stable performance, and high system construction efficiency. The test sample size for the proposed method is reduced to about 1/10 than that of the traditional method. The proposed 3-port PIM test method provides support for the rapid research of novel low-PIM-level metal meshes.