分置型近场多输入多输出（MIMO）雷达的回波幅度因收发机相对于目标角度的不同而存在差异，为此提出了一种基于波束指向调整的MIMO雷达回波幅度校准方法。利用天线波束指向与回波幅度变化的转换关系，通过波束指向调整实现对天线回波幅度的间接调整，从而校准各通道间回波幅度的差异。同时利用一种常规的几何分置型MIMO阵列对所提方法进行了验证。研究结果表明，回波幅度差异校准能显著地提升近场分置型MIMO雷达的成像性能。

The echo amplitude of near-field separated multiple-input multiple-output （ MIMO） radar is different due to the different angle of each channel relative to the target. Therefore, a method of echo amplitude calibration based on beam pointing adjustment is proposed. By using the conversion relationship between the antenna beam pointing and the echo amplitude change, the indirect adjustment of the antenna echo amplitude is realized by adjusting the beam pointing so that the difference of echo amplitude between channels could be calibrated. The proposed method is verified by using a conventional geometrically separated MIMO array. The results show that the imaging performance of near-field separated MIMO radar can be improved significantly after the calibration of echo amplitude difference.