建立双基地SAR的单基地等效模型, 分析了系统时间同步误差的机理; 提出了双基地SAR回波中的直达波数据进行时间同步误差校正的算法; 在双基地SAR单站等效模型的基础上, 利用时变阶梯变换算法进行成像处理。经过理论分析, 实测数据处理验证, 这一算法是有效的, 能够校正双基地SAR时间同步误差, 较好地进行实测数据的成像处理。

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.