系统工程与电子技术

• 传感器与信号处理 • 上一篇    下一篇

#br# 解析搜索偏移量的InSAR图像精配准方法

薛海伟, 冯大政   

  1. (西安电子科技大学雷达信号处理国家重点实验室, 陕西 西安 710071)
  • 出版日期:2016-07-22 发布日期:2010-01-03

Analytic offset search method for InSAR image precise registration

XUE Hai-wei, FENG Da-zheng   

  1. (National Lab of Radar Signal Processing, Xidian University, Xi’an 710071, China)
  • Online:2016-07-22 Published:2010-01-03

摘要:

基于插值的干涉合成孔径雷达(interferometric synthetic aperture radar,InSAR)图像配准方法能够达到亚像素精度,但配准精度取决于插值单元尺度,且计算量会随精度要求提高大幅增加。提出了一种将图像配准过程转化为连续函数优化问题的精配准方法。首先,该方法通过整合插值和互相关函数搜索过程构造了一个解析代价函数,在连续域内搜索的偏移量精度不依赖于插值单元,提高了配准精度;然后利用该代价函数对于偏移量参数的梯度信息,采用拟牛顿法来优化代价函数,快速收敛并得到与最优值对应的亚像素偏移量,具有较低的运算量。实验结果表明该方法与传统方法相比有更高的配准精度,且在计算复杂度方面有较大改善。

Abstract:

In the interpolationbased methods for subpixel registration of interferometric synthetic aperture radar (InSAR) images, but the registration accuracy is restricted by the interpolation unit, and the computational burden is heavy when high accuracy is demanded. The proposed method implements the analytical optimization of cross correlation to overcome the limitation aforementioned. Firstly, a novel analytic cost function is derived by combining the interpolation operation with the crosscorrelation searching process. The offset is searched in the continuous domains, which suggests a more accurate registration since the estimation accuracy does not depend on the interpolation unit. Then, by incorporating the gradient information of the cost function, the quasiNewton method is employed to optimize the cost function. The subpixel offset associated with the maximum of the cost function can be quickly obtained with low computational complexity. The experimental results show that the proposed method has higher registration accuracy and superior performance in terms of registration accuracy and computational complexity when compared with several conventional methods.