星载微波辐射成像仪天线温度误差分析

ANALYSIS ON THE ANTENNA RADIOMETRIC TEMPERATURE ERROR OF SPACEBORNE MICROWAVE RADIATION IMAGER

：阐述了星载微波辐射成像仪扫描式外部两点周期定标原理，介绍了利用星载微波辐射成像仪原始测量数据计算其天线温度的方法———定标方程。详细分析了星载微波辐射成像仪的天线温度精度。并估算了星载微波辐射成像仪的１８ＧＨｚ接收通道天线温度精度。确定了影响天线温度精度的主要误差源。

This article illuminates the external two points periodic calibration principle of spaceborne Microwave Radiation Imager(MWRI). The calibration method to calculate the antenna radiometric temperature with original data of MWRI——the calibration equation is given. The error sources of MWRI's antenna radiometric temperature are analyzed. The formula of MWRI's antenna radiometric temperature accuracy is derived. The antenna radiometric temperature accuracy of 18.7 GHz receive channel of MWRI is calculated. Through analysis, the main error sources affecting antenna radiometric temperature accuracy are ascertained. Those analytic conclusions provide the important criteria for improving the antenna radiometric temperature accuracy.