毫米波合成孔径雷达（Ka-SAR）进行俯仰向数字波束形成（digital beam forming,DBF）车载地面验证时，由于车载高程较小使得成像区域地形起伏不可忽略。采用传统扫描接收（scan on receive,SCORE）算法获得的DBF加权系数会存在误差，使合成波束方向图偏离理想状态，降低系统性能。针对上述问题，本文提出了一种基于多通道SAR的自适应距离向DBF处理算法，对多通道数据进行干涉处理，并通过滤波提取干涉相位，自适应生成加权系数，提高了接收增益。该自适应算法获得的加权系数精度较高，具有处理流程简单、运算量小、便于实时处理的特点。最后，基于仿真和车载实验数据成像，验证了该算法的有效性。
The directional deviation on the topographic relief of the image arising from the low height of the vehicle is nonnegligible during the verification of digital beam-forming (DBF) using Ka-band automotive synthetic aperture radar (Ka-SAR). Due to the inevitable errors of the DBF weight coefficients using scan on receive (SCORE) algorithm, the synthetic beam pattern would deviate from the ideal state and degrade the system performance. In this paper, an adaptive range DBF processing algorithm based on multi-channel SAR is proposed. The DBF weighting coefficients are adaptively generated by interference processing and phase extraction, which improves the receiving gain. The adaptive algorithm has the advantages of high precision, simple processing flow, low computational load and real-time implementation. Finally, the effectiveness of the algorithm is verified based on simulation and experimental data.
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