一种基于最小二乘法的星载ScanSAR滚动角迭代估计算法
doi: 10.3724/SP.J.1146.2007.00239
A ScanSAR Roll Angle Iterative Estimation Algorithm Based on Least Square Method
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摘要: 该文对于ScanSAR辐射定标中的滚动角估计问题进行了研究，重点分析了波束间相对偏差对于滚动角估计算法的影响。在此基础上提出了一种改进算法，该算法的估计模型中不仅考虑了波束间的相对增益偏差，而且考虑了波束间的相对角度偏移。对估计模型进行线性化处理后，可利用最小二乘法来迭代求解滚动角。通过仿真实验，分析了该算法在不同信噪比情况下的估计精度，并将其与Dragosevic的算法进行了比较，证明了该算法的优良性能。Abstract: This paper works on a critical issue of roll angle estimation in ScanSAR radiometric calibration. After a deep analysis of the relative discrepancies between constituent beams, an improved algorithm is proposed, whose estimation model takes into account both the relative gain discrepancy and the relative beam angular placement between constituent beams. By linearizing the estimation model, an iterative solution of the roll angle can be achieved by means of least square method. Through simulation the estimation accuracy of the proposed algorithm is evaluated under different SNR levels and compared with Dragosevics algorithm. The superiority of the proposed algorithm is proved with the results.
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