External calibration of a polarimetric synthetic-aperture radar for a limited number of types of reference reflectors

Capabilities of the external calibration of a polarimetric synthetic-aperture radar (SAR) and the monitoring of the radar parameters under flight conditions for a limited number of types of reference calibration targets are determined. An analytic form of the algorithm for neutralization of SAR hardware distortions in the measurement of the scattering matrix of the observed object is proposed and possibilities for application of this algorithm under the conditions of unrealizable total polarimetric calibration are analyzed. The possibilities of determining the particular calibration parameters and their combinations with the use of one or two reference reflectors are analyzed. It is shown that, in the measurement of the scattering matrix of a reciprocal object, it is sufficient to use two types of reference reflectors.