Optimal polarimetric detection of radar target in a slowly fluctuating environment of clutter

It is shown that it is possible to improve the radar detection performance by using appropriate signal processing on two orthogonal polarization states. A CFAR (constant false alarm rate) polarimetric detection system based on the study of the polarization difference between clutter and target is proposed. Considering that the polarization state of the clutter echoes fluctuates slowly from cell to cell, an autoregressive model is applied to the components of the polarization vector in order to predict the detection thresholds that are able to follow the polarization state variations. The detection thresholds are determined to maintain a false alarm probability equal to 10^-6. Results obtained from measurements of a simple and canonical target with artificial clutter validate the principle of the polarimetric detection