Modified polarimetric whitening filter for polarimetric SAR data

To preserve the power information in the output of polarimetric whitening filter (PWF), a modified PWF is proposed for polarimetric synthetic aperture radar (PolSAR) imagery. Besides minimizing the standard deviation to mean ratio, the modified PWF also requires its output closest to the original polarimetric vector in a minimum mean-square error sense. This principle is consistent with that of the minimum mean-square error covariance shaping. A real PolSAR image derived by SIR-C is applied for the illustration. The experimental results demonstrate that the speckle reduction performance of PWF is enhanced by the proposed modification and the power information is well preserved in the output of the modified PWF.