Sar Image Registration And Change Detection

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. 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, The definition of image registration is given, the general steps; combination of improved energy distribution of the image is presented based on energy distribution of the SAR image registration; obvious target for the strong scattering of SAR images is proposed based on moment invariant of the automatic registration method. The results confirmed that both methods have good stability of the algorithm, registration accuracy.Finally, We study the SAR image change detection algorithm. Summarize the basic method of image change detection and assessment of the general method of detecting effect; improvement is presented based on principal component analysis for sub-image change detection algorithm; In addition, this paper proposes a maximum likelihood estimation based on change detection algorithm. Wider application of these two methods can achieve good test results.