Antenna Cross-Polarization Isolation and Calibration of Hybrid-Polarization Radars

This letter presents an experiment using a fully polarimetric hybrid-polarization (CL-pol) radar that employs separate spiral antennas for transmit of the orthogonal circular polarizations and operates from 8 to 16 GHz. We propose a model for the antenna cross-polarization isolation (XPI) and calibration of this radar. The transmit XPI is characterized by leveraging the Doppler shift caused by a continually rotating dihedral target illuminated by a circularly polarized wave. Experimental results show the validity of the radar model and antenna measurement technique .