一种基于似然比统计量的SAR相干变化检测

Change Detection in SAR CCD Based on the Likelihood Change Statistics

相干变化检测利用相位差异可以检测出场景中的微小变化。该文针对相干变化检测中的两个问题:虚警高和阈值难选择,在原有似然比检测算法的基础上做了两点改进:运用最大似然估计优化似然比统计量中的参数,并采用邻域滑动窗口使得参数估计结果更加准确稳健;根据差异图像直方图提出了一种基于邻域直方图差的自动阈值选取方法。实测数据处理结果验证了算法的有效性。

The Coherent Change Detection（CCD）measures the phase difference in repeat passes in SAR images and is a powerful technique for detecting minute changes between two synthetic aperture radar images taken at different times.Nevertheless,the CCD has two problems.These are the high false-alarm rates and threshold selection.To deal with these problems using the likelihood change,this study makes two improvements.First,the model parameters are optimized by the maximum likelihood method and more accurate and robust parameters are obtained by using the sliding window in the neighborhood operations.Second,the automatic change in the threshold method is proposed based on the histogram characteristics of different data.The processing of real data suggests that the proposed method is effective in detecting minute changes.