摘要
针对某致冷接收机系统等效噪声温度测试数据存在较为显著的疑似驻波问题,对测量数据进行了振幅谱分析和周期函数拟合。首先设计了分析方法,通过模拟数据对方法进行了有效性检验。之后分析了实测数据,并针对测量误差较大的问题,采用了事先平滑的处理方法,显著降低了拟合参数的不确定性,得到了各周期分量较为准确的特征参数,为后续链路和器件驻波的排查与处理、致冷接收机系统的调试提供了参考。
Amplitude spectrum analysis and periodic function fitting were performed on the equivalent noise temperature measurements of a cooled receiver system due to the existence of significant possible standing waves. Analysis procedure was designed and validated via simulation data. Real measurements were then analyzed to determine the characteristic parameters of significant periodic components. The uncertainty of parameters was dramatically reduced by applying pre-smoothing treatment.Amplitudes and periods of significant components were precisely determined. It may provide valuable reference for the subsequent cause analysis of standing waves in the signal chain and devices as well as in the debugging of the cooled receiver system.
引文
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