Polarimetric Cross-Talk in SAR System Induced by Antenna Cross-Pol Pattern

Abstract:
Calibration of polarimetric radar systems has been widely considered. Preferred calibration methods are based on comparing the statistics of measured and processed data to those of theoretical models for natural targets with azimuthal symmetry. Those methods aim to remove the correlation between the co- and cross-pol channels, induced by imperfect system isolation between channels. A drawback of those calibration methods is that cross-talk with uncorrelated co- and cross-polarized components is not removed. This paper shows that the antenna induces a cross-talk in the cross-polarized channel that is uncorrelated with the co-polarized channels and will therefore not be calibrated with common polarimetric calibration methods.