InSAR中应用可靠度导向改进的分级表相位展开算法  

Reliability-guided phase unwrapping algorithm based on improved classification table for InSAR

作　　者：宋芳[1,2] 李勇[3] 余涛[1] 

机构地区：[1]中国科学院遥感与数字地球研究所,北京100094 [2]装备学院,北京101416 [3]浙江师范大学信息光学研究所,金华321004

出　　处：《中国图象图形学报》2015年第12期1699-1704,共6页Journal of Image and Graphics

基　　金：中国科学院基础研究项目(Y3SG1100CX)

摘　　要：目的在干涉合成孔径雷达的相位展开过程中,如果相位展开的展开路径穿过残差点就会产生相位展开的误差。在相位展开的时候,希望将相位展开的误差限制在局部区域,提高相位展开的精度。方法首先通过判断截断相位图的残差点,并以In SAR的干涉一致性图作为相位展开的可靠性度量,对截断相位图进行量化,将残差处的可靠度设为排序中的最低等级。在进行可靠度排序后进行干涉合成孔径雷达相位图的相位展开。结果使用该算法改进了经典可靠度导向相位展开算法中可靠度排序的缓慢问题。与经典菱形算法相比,展开精度高很多。与洪水算法相比,展开速度能快上百倍。通过可靠度排序的改进,对干涉合成孔径雷达相位展开后的结果进行分析,可以看到提高了相位展开的精度,有效的控制了相位展开过程中误差的传递。结论相位展开算法的改进提高了干涉合成孔径雷达相位展开的精度,在干涉合成孔径雷达的相位展开中可以广泛应用。Objective In the process of phase unwrapping of InSAR, the error of phase unwrapping can be gained if unwrap- ping path is on the residual error point. Our objective is limiting the error of phase unwrapping in local region. Method The coherence map of InSAR is used as reliability map for phase unwrapping and is quantized with given level. The residues of wrapped phase are found and then their reliability is set to the lowest level. Phase unwrapping is carried out after reliability reordering. Result The algorithm using classifieation table is adopted instead of the slow classical reliability-guided phase unwrapping algorithm. The experiments were carried out to verify the proposed method. The speed of our method is faster than classical reliability-guided algorithm in the experiments. The phase unwrapping results of InSAR show enhanced accu- racy, and the error propagations are effectively controlled. Conclusion The experimental results prove the proposed method is accurate and applicable for InSAR＇s phase unwrapping.

关 键 词：合成孔径雷达干涉测量 干涉一致性图 二维相位展开 残差 

分 类 号：P237[天文地球—摄影测量与遥感]