考虑干涉相位噪声的PSI组合及其沉降监测应用

摘要

为了提高PSI沉降监测的精度,在常用干涉组合方式的基础上,同时考虑空间基线和时间基线阈值以及各干涉对的干涉相位噪声限制,提出一种新的干涉组合方式.选取上海市局部区域作为实验区,以16幅TerraSAR-X(TSX)影像为数据源,采用考虑干涉相位噪声的PSI干涉组合方式进行地表沉降监测.研究结果表明,与已有的干涉组合方式相比,本文提出的干涉组合方式获取的干涉对数量最少(92对),PS个数最多(27 026个),与水准测量数据进行比较,年沉降速率中误差为±3.89 mm/a,比已有的干涉组合方式的精度平均提高1.86～3.00倍,证实了该干涉组合方式的有效性和可靠性.%In order to improve the accuracy of persistent scatterer interferometric (PSI) synthetic aperture radar for monitoring ground deformation,an improved interferometric combination mode was proposed by considering the thresholds of both spatial and temporal baselines,and taking into account the noise level in interferometric phases of all interferometric pairs.Experiments of subsidence monitoring using the proposed interferometric mode were performed using 16 high resolution SAR images collected by the X-band radar sensor onboard the German satellite TerraSAR-X over Shanghai.The results show that the minimum interferometric pairs (92) and the maximum persistent scatterer (PS) points (27 026) can be obtained by the proposed method.Compared with the ground-based measurements,the subsidence rate derived by the PSI technique has an error of + 3.89 mm/a,with a precision being 1.86-3.00 times higher than that of other available modes.This demonstrates the effectiveness and reliability of the proposed interferometric mode.