Correction of ionospheric dispersion for spaceborne SAR based on dual-antenna scheme

The propagation of spaceborne synthetic aperture radar (SAR) signal is affected by the ionosphere, which will lead to the degradation of the imaging quality, especially in the conditions of low frequency and wide bandwidth. A method of correcting ionospheric dispersion for SAR images based on the dual-antenna scheme is proposed in this paper. The ionospheric phase distortion is calculated by the time delay difference between the subband interferograms, which are obtained through split-spectrum and interference processing. It can be used in both single- and full-polarimetric SAR system. The simulation results show that the proposed method can estimate TEC in different ionospheric environments, and the performance is free from the constraint of the scene’s homogeneity.