对于高速运动目标，在一段长的相干处理间隔内，其径向速度和径向加速度带来的跨距离单元和多普勒频率扩散现象无法忽视，目标高速运动带来的速度模糊问题也需要得到解决。针对此，提出一种基于运动参数估计的高速目标检测方法，通过分段相干积累的方式抑制各分段下的跨距离单元现象，将分段下的积累峰值位置作为参数估计输入的样本点，通过搜索获得目标径向加速度并构造滤波器对回波相位中的非线性分量进行补偿，利用Keystone变换结合模糊项补偿校正雷达回波的跨距离单元现象，最后通过方位向FFT实现对高速目标回波信号的相干积累。
Coherent accumulation over a long period of time has been an effective means to enhance radar echo energy. However, for high-speed moving targets, within a long coherent processing interval, across range unit (ARU) and Doppler frequency migration (DFM) caused by their velocity and acceleration in the radar radial direction cannot be ignored. Additionally, the velocity ambiguity problem caused by high speed also needs to be addressed. This paper proposes a high-speed target detection method based on motion parameter estimation. By segmenting coherent accumulation, the ARU under each segment is suppressed. The peak position of the echo after accumulation under each segment is used as a sample point for parameter estimation input. A filter is constructed using the target radial acceleration obtained through searching to compensate for nonlinear components in the echo phase. Finally, keystone transform is used in conjunction with velocity ambiguity term compensation to correct ARU in radar echoes, and coherent accumulation of the high-speed target echo signal is achieved by performing FFT along the azimuth.
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