Amplitude and Phase Errors Correction Method for FMCW Array SAR System Using Single Prominent Point Echo

Frequency Modulated Continuous Wave (FMCW) array antenna SAR system combines the FMCW and array antenna imaging technology, which is of abroad interest in both civil and military applications. While in practical FMCW array SAR, the presents of unavoidable sweep rate non-linearity error in the frequency modulation and the multi-channel amplitude/phase errors severely degrade the reconstruction image quality. The signal model with sweep rate non-linearity error and multi-channel amplitude/phase errors is proposed in this paper. An error calibration scheme and data processing flow chart based on single prominent point echo are presented. Extensive simulations and real data processing are performed to validate the effectiveness of the proposed calibration scheme.