The signal processing in the bistatic SAR case is more complex than the monostatic synthetic aperture radar （SAR） case due to issues such as the range history of the target echo signal, time synchronization error, time-varying Doppler rate because of squint, etc. In this paper, a monostatic equivalent geometry model of bistatic SAR is established; the mechanism of the System time synchronization error is analyzed; a time synchronization error correction method based on direct-path signal is presented; a modified time-varying step transform algorithm is used for bistatic SAR. Theoretical analysis and experimental data processing confirmed the effectiveness of the algorithm.

bistatic;synthetic aperture radar;time synchronization;imaging algorithm