A Novel Polarization Evaluation Method Utilizing LT-1 Calibrators

The accuracy of the polarimetric evaluation of low frequency polarimetric synthetic aperture radar (PolSAR) systems based on distributed targets is uncertain when the ionospheric information is unknown. Therefore, in this paper we investigate the potential of polarimetric evaluation of LT-1 images based on a set of calibrators arranged for L-band LT-1 PolSAR images. First, reasonable assumptions are made for common calibration models for LT-1 images. The ideal backscatter matrix of the set of calibrators is subsequently used in conjunction with the polarimetric distortion matrices (PDMs) to construct constraints for solving the PDMs. Finally, for possible ambiguous values of the solution, we use phase consistency as well as the Frobenius norm to remove the ambiguous values of the PDMs and obtain the final evaluated results. In the experimental part, we verify the feasibility of the method based on simulation data. Thus, the method contributes to accurate evaluation of LT-1 images.