Estimation and Correction for the Roll Angle Errors of a Switchable DAPARC

Precise acquisition of the polarimetric scattering matrices for reference calibrators is of great importance in radar polarimetric calibration. However, during the assembly or measurement, incomplete installation might introduce unexpected roll angle errors (RAEs) between the calibrators and the radar line of sight, thereby resulting in additional calibration errors. In this paper, a technique for estimating and correcting for the RAEs of the switchable double-antenna polarimetric active radar calibrator (DAPARC) is proposed to improve its calibration performance.