Multi-polarization SAR change detection: unstructured versus structured GLRT

The problem of coherent multi-polarization SAR change detection exploiting data collected from N multiple polarimetric channels, is addressed in this paper. The change detection problem is formulated as a binary hypothesis testing problem and a special block-diagonal structure for the polarimetric covariance matrix is forced to design a novel detector based on the Generalized Likelihood Ratio Test criterion. It is shown that the new decision rule ensures the Constant False Alarm Rate (CFAR) property. At the analysis stage, results on both simulated and real high resolution SAR data show the effectiveness of the proposed decision rule and its superiority against the traditional unstructured GLRT in some scenarios of practical interest.