干涉雷达永久散射体自动探测——算法与实验结果

Abstract

基于理论与模拟实验分析,提出并实现“双重阈值”PS自动探测算法,即时序相关系数阈值法和振幅离差指数阈值法相结合,达到PS自动探测时间效率与可靠性的统一。选用覆盖上海地区的26幅ERS-1/2 C波段SAR图像(1992~2002年),双重阈值PS探测算法得到了检验,实验结果表明,该方法能够有效地提取可靠的PS目标。 The time-series differential radar interferometry with Permanent Scatterers(PS) can overcome the limitation of temporal decorrelation,and thus enhance the reliability of radar interferometry when applied in regional deformation mapping.How to detect automatically PS from SAR images is one of crucial procedures in data reduction of the PS interferometric system.With theoretical and experimental analysis,this paper proposes a Dual-Thresholding Algorithm(DTA) for automated identification of PS.Since the DTA is of the combination of both correlation-coefficient thresholding and amplitude dispersion index thresholding,it can save computation time and keep reliable for PS identification.Using 26 C-band SAR images collected from 1992 to 2002 over Shanghai by satellites ERS-1 and ERS-2 of European Space Agency,the DTA has been validated for PS detection.The testing results show that the proposed DTA can identify PS from SAR images effectively and reliably.