Sar Image Change Detection Studies

Change detection is a process that analyzes a pair of images acquired on the same geographical area at different times in order to identify changes that may have occurred between the considered acquisition dates. The major advantage of synthetic aperture radar (SAR) is its all-weather capability that allows the acquisition of time series of imagery with exact acquisition dates under all climatic conditions. SAR image change detection techniques have been used successfully in many applications, such as environmental monitoring, study on land-use/land-cover dynamics, analysis of forest or vegetation changes, damage assessment, agricultural surveys, and analysis of urban changes. This paper research change detection technology and the related technology using synthetic aperture radar image.Firstly, the basic characteristics of SAR image are introduced, including the differences between SAR images and optical images, the geometric characteristics,statistical distribution,speckle noise of SAR images, comparing several classic de-speckle noise algorithms by experiments.Secondly, this paper analyses SAR image registration technique. Image registration is defined. The image registration algorithms and the common registration accuracy assessment methods are systematically summed up. Combining CFAR target detection and Delaunay triangulation, this paper proposes a new SAR image registration algorithm. The experimental results verify the effectiveness of the proposed algorithm.Finally, SAR image change detection algorithm is studied, including introduction of the basic steps of SAR image change detection, survey image change detection methods and the basic assessment of the effects of the detection methods. Based on the principal component analysis, this paper proposes a SAR image change detection algorithm. Compared with the methods based on the Log-Ratio and Multi-Block PCA,it is proved to be more valid and effective.