Space-surface BiSAR based on GNSS signal: Synchronization, imaging and experiment result

This paper presents a novel synchronization method for space-surface BiSAR (SS-BiSAR) illuminated by navigation satellites. Direct signal is utilized to obtain theoretical Doppler and navigation data. According to the navigation data and receiver position, theoretical Doppler history can be calculated. Comparing the tracking result and theoretical result, phase synchronization error could be estimated. After phase synchronization error is estimated and compensated, echo of SS-BiSAR is focused by bistatic back-projection algorithm. The proposed method has been verified by SS-BiSAR imaging experiment based on BeiDou signal.