利用定标站对旋转扫描扇形波束散射计的信号频率估计

Signal Frequency Estimation for Rotating Fan-beam Scatterometer Using Ground Calibration Station

该文基于中法海洋卫星(Chinese-French Oceanic Satellite,CFOSAT)雷达散射计系统参数,给出了可行的在轨Doppler预补偿方法并利用地面定标站实现对RFSCAT信号频率的估计。对比了3种信号频率估计方法,通过仿真分析表明,可达到优于0.05k Hz的频率估计精度。仿真结果表明,通过把估计的频率与Doppler预补偿查找表和Doppler频率进行比较,可实现对RFSCAT在轨Doppler预补偿状态及生命周期内的载频漂移监测。

Based on system parameters of the rotating fsn-beam scatterometer （RFSCAT） onboard Chinese-French oceanic satellite （CFOSAT）,a proper Doppler pre-compensation algorithm for RFSCAT is given and RFSCAT signal frequency is estimated using Ground Calibration Station （GCS）.Three frequency estimation algorithms are compared and their frequency estimation accuracies are better than 0.05 kHz.The data used in this paper is acquired by GCS during satellite passing overhead.Analysis of data received by GCS,the scatterometer Doppler compensation frequency and the Doppler frequency shift are examined for deviation from nominal values,and simulations result show that it is able to monitor and determine the scatterometer carrier frequency drift over its life cycle.