Correlation Coefficients Between Polarization Signatures for Evaluating Polarimetric Information Preservation

In order to evaluate quantitatively the preservation performance of polarimetric information for polarimetric synthetic aperture radar (PolSAR) speckle filters, this letter presents correlation coefficients between the original and the filtered polarimetric data based on the theory of polarization synthesis. The copolarized and the cross-polarized correlation coefficients are furthermore discussed in cases whether the transmitting and receiving radar antennas are characterized by the same or orthogonal polarization state. To show how these coefficients can be exploited in evaluating the preservation of polarimetric information, they are demonstrated with a German Aerospace Center (DLR) Experimental Synthetic Aperture Radar L-band full-polarized image of the Oberpfaffenhofen Test Site Area (DE), Germany, which was obtained on September 30, 2000. Results make evident that the correlation coefficients are efficient to describe quantitatively the performance in preserving polarimetric information for PolSAR speckle filters.