LAUSR

Abstract. The speckle reduction problem for polarimetric synthetic aperture radar images is a complex issue due to difficulties on preserving polarimetric information. Several filters have been developed for this purpose such as Novak filter, enhanced Lee filter, and wavelet filters. We present an improved version of the Li filter by adding two false alarm detectors to enhance target appearance. These detectors are applied according to the homogeneity nature of the area to filter. The filtering process is performed by carrying a filtering step for each part of the SLC SAR image, intensity, and phase, independently from each other and using a contour detection technique to maintain the linear structures in the images. A comparative study with enhanced Lee filter is done and allows to conclude that introducing constant false alarm rate detectors gives the expected results: better targets (or reflectors) preservation, smoothing homogeneous regions, and details preservation.