星载ScanSAR天线指向稳定度对辐射校正的影响

Effects of Stability of Antenna Pointing on Spaceborne ScanSAR Radiometric Correction

基于均匀加权天线模型,推导星载ScanSAR天线指向不稳定引起的多普勒中心频率估计误差,建立多普勒中心频率估计误差与图像辐射校正精度之间的数学模型,进而提出星载ScanSAR辐射校正对天线指向稳定度的要求。最后,通过计算机仿真,验证了理论分析的正确性。

Based on the uniform weighting antenna model,the Doppler center frequency error from the instability of antenna pointing is derived in detail for the spaceborne scanning synthetic aperture radar(ScanSAR) system.And the effects of Doppler center frequency error on image radiometric correction are analyzed.The basic precision of the antenna pointing stability is presented for the offsets of ScanSAR image radiometric correction,which has been verified by simulations.