一种结合边缘检测的多基线InSAR高程反演方法  

A Multi-baseline InSAR Elevation Reconstruction Method Combined with Edge Detection

作　　者：梁小星 谢先明[1] 孙玉铮 LIANG Xiaoxing;XIE Xianming;SUN Yuzheng(Guilin University of Electronic Technology,Guilin,Guangxi 541004,China)

机构地区：[1]桂林电子科技大学,广西桂林541004

出　　处：《遥感信息》2021年第1期102-111,共10页Remote Sensing Information

基　　金：国家自然科学基金项目(41661092、61961009);广西自然科学基金重点项目(2016GXNSFDA380018);广西自然科学基金项目(2018GXNSFAA281196);广西无线宽带通信与信号处理重点实验室基金项目(GXKL06180102)。

摘　　要：针对多基线InSAR高程重建算法鲁棒性差的问题,提出一种基于边缘检测与路径跟踪策略的多基线InSAR高程反演算法。该算法分为2个步骤。第1步是直接利用多基线最大似然估计算法从多幅不同基线的干涉相位图中获取粗略的地形高程,再用Sobel算子对滤波后的粗略地形高程进行边缘检测,获得地形的不连续边界;第2步则先构建优化的多基线InSAR高程反演模型,随后利用单通道InSAR相位解缠技术中的路径跟踪策略,引导构建的多基线InSAR高程反演模型沿高质量像元到低质量像元的路径进行高程重建,在连续区域引入邻域约束,在不连续区域则阻断邻域约束,既有利于提高算法在连续区域的抗噪性,又可避免邻域约束在不连续区域引起的误差传递现象,从而达到增强算法鲁棒性的目标。多组不同地形的高程反演结果证明了该方法的有效性。Aiming at the problem of poor robustness of multi-baseline InSAR elevation reconstruction algorithm,a multi-baseline InSAR elevation reconstruction algorithm based on edge detection and path tracking strategy is proposed.The algorithm can be divided into two steps.Firstly,the rough terrain elevation can be obtained from interference phase maps of different baselines directly by using the multi-baseline maximum likelihood estimation algorithm,and then use the Sobel operator to perform edge detection on the filtered rough terrain elevation to obtain the discontinuous boundary of the terrain.Secondly,an optimized multi-baseline InSAR elevation reconstruction model is constructed,and the path-following strategy applied in single-channel InSAR phase unwrapping algorithms is utilized to guide the constructed multi-baseline InSAR elevation reconstruction model to reconstruct the maps of the elevation along the paths from the high-quality pixels to low-quality pixels.To enhance the robustness of the algorithm,the noise resistance of the algorithm is improved by introducing the neighborhood constraint in the continuous regions.On the other hand,the error transmission is avoided by blocking the neighborhood constraint in the discontinuous regions.The elevation reconstruction results with different terrains demonstrate the effectiveness of the proposed method.

关 键 词：高程重建 边缘检测 能量函数 最大似然估计 最大后验估计 

分 类 号：P236[天文地球—摄影测量与遥感]