PSI技术在地表形变监测中的应用研究

Application of PSI technique in deformation monitoring

基于时序SAR影像准确识别PS是永久散射体合成孔径雷达干涉(PSI)技术建模及形变信息提取中最为关键的问题之一。本文提出了一种改进的PS探测算法,它是基于时序SAR影像的振幅信息,利用振幅和振幅离差指数双阈值法获取PS候选点,对所有候选点进行相位稳定性分析,筛选出既满足雷达反射强度高、又符合散射稳定性要求的真实PS点,并基于所选PS点提取形变信息。实验结果表明,相比于已有PS探测方法,本文所提出的方法能够更准确、可靠地识别出时序SAR影像中的PS目标,进而提高了PSI形变探测结果的精度和可靠性。

The accurate identification of PSs is one of the key issues in Persistent Scatterer （PS） Synthetic Aperture Radar Inter- ferometry （InSAR） modeling and deformation extraction. The paper presented an improved algorithm for PS detection. Based on the time series of SAR amplitude data, the PS candidates （PSC） were firstly selected using both amplitude thresholding and amplitude dis- persion index thresholding. The true PSs were then screened out from the PSC set by an iterative process based on phase stability analy- sis. The deformation values of the true PSs were finally estimated. Experimental results demonstrated that the proposed algorithm could significantly improve the accuracy and reliability of deformation measurements derived with PSI.