静止轨道微波辐射计多反射面天线容差测试

Tolerance testing of multi-reflector antennas for geostationary orbit microwave radiometers

静止轨道微波辐射计天线由3个大口径反射面组成,天线在轨外热流复杂,反射面及其支撑结构因温度剧烈变化会发生大尺度变形,导致天线主波束效率下降,波束指向偏差。本文开展天线反射面单自由度容差分析,基于全自动多自由度载荷容差分析系统,获取反射面形位误差与主波束效率、波束指向之间的关系,并基于蒙特卡洛容差分析方法对各自由度容差值的正确性进行验证。最后采用近场测试系统测试天线容差状态下的主波束效率和波束指向,并将容差实测值与半物理仿真值和设计值进行比对分析,验证了容差分析的正确性。

The geostationary orbit microwave radiometer antenna is composed of three large diameter reflectors.The orbit heat flow is complex.The reflector and its supporting structure will undergo large-scale deformation due to severe temperature changes.This leads to a decrease in the efficiency of the main beam and a deviation of the beam pointing.The single-freedom tolerance analysis of the antenna reflector is carried out.Based on the fully automatic multi-freedom tolerance analysis system,the relationship between antenna mechanical error and electrical performance is obtained.And the correctness of the tolerance value of each freedom is verified based on the Monte Carlo tolerance analysis method.Finally,the near-field test system is employed to test the main beam efficiency and beam pointing under the antenna tolerance state.Comparing and analyzing the measured tolerance value with the semi-physical simulation value and design value verifies the correctness of the tolerance analysis.