Nonlinear Calibration of Polarimetric Radar Cross Section Measurement Systems

Polarimetric radar cross section measurement systems are characterized by polarimetric system parameters epsilon(h) and epsilon(v). These parameters can be measured by use of rotating dihedrals. The full polarimetric dataset as a function of the angle of rotation can be analyzed with a nonlinear set of calibration equations to yield the system-parameter complex constants and the four polarimetric-calibration amplitudes. These amplitudes appropriately reproduce the system's drift, and very accurately satisfy a drift-free system-configuration criterion. The results indicate that the nonlinear approach is better than the previously studied linear approach, which yielded system parameters that were seriously distorted by system drift.