基于多普勒搬移机理的机载MIMO雷达慢速目标检测方法

For an airborne radar system, the detection of moving target under the ground clutter has become the research hotspot to worldwide scholars. And the detection of the slow-moving target near the main clutter area is now regarded as one of the difficulty problem. In order to reduce the Minimum Detectable Velocity (MDV) of moving target, we propose a novel research idea and signal processing algorithm in this project. Firstly, the Doppler frequency movable waveform (DFMW) and its modulation effect on target and clutter environment will be studied, and the mechanism of the expansion of the Doppler frequency difference between slow-moving target and clutter will be revealed, based on which, the parameter designed methods of the DFMW and the Doppler frequency non-linear transforming methods will be put forward. Secondly, to avoid the range ambiguity and perturbation happening in the traditional high frequency airborne phased array radar system and reduce the computational load in multiple input multiple output (MIMO) radar signal processing procedure, the collaborative work mechanism of the MIMO radar system and the DFMW will be studied, the signal model will be established, based on which, the space-time processing method will be proposed for clutter suppression and target detection. By combining the advantages of the MIMO radar and the DFMW, the method proposed in this project could realize the suppression of ground clutter and the detection of the slow-moving target near main clutter area effectively. We believe that this project can provide a new technical way for slow-moving target detection in airborne radar system, and thus improve the airborne radar surveillance ability for China, which has an important theoretical significance and practical value.

机载雷达对地杂波背景下运动目标检测是国内外研究的热点问题，其中，非均匀杂波背景下检测靠近主杂波区的慢速目标是目前研究的难点之一。为了进一步降低运动目标的最小可检测速度，本项目提出了一种新颖的研究思路和处理方法，拟研究多普勒频率可搬移波形及其对目标和环境的调制效应，揭示慢速目标多普勒频率搬移出杂波区机理，提出多普勒可搬移波形参数设计方法和慢速目标回波搬移出杂波区的方法；拟研究机载MIMO体制与多普勒可搬移波形的协同工作机制，提出 “多普勒可搬移波形+MIMO空时处理”的解决方案，建立多普勒可搬移波形条件下的机载MIMO信号模型，提出适于非均匀、非平稳杂波的杂波抑制和目标检测方法，实现主杂波区附近慢速目标的有效检测。本项目巧妙地将多普勒可搬移波形与MIMO雷达的优势相结合，为机载雷达检测慢速目标提供了新的技术途径，对于提升我国机载雷达预警探测能力具有重要的理论意义和实用价值。

本项目将多普勒可搬移波形与MIMO 体制相结合，通过研究多普勒频率可搬移波形及其优化设计、多普勒搬移变换对杂波分布特性影响的机理和机载MIMO 雷达空时信号处理方法，提高了地杂波抑制和慢速目标检测的能力，获得更优的MDV 性能。具体研究内容如下：（1）深入研究了频率步进这一类多普勒可搬移波形对运动目标的搬移机理，提出了频率步进波形参数优化设计的方法，并设计了相应的搬移算法；（2）建立了基于多普勒可搬移波形的机载MIMO雷达杂波空-时-波形三维联合模型，并分析了杂波的空时分布特性；（3）在上述模型的基础上，提出了多普勒可搬移波形条件下机载MIMO雷达慢速目标的检测方法。此外，利用机载MIMO雷达单快拍数据等效为传统机载相控阵雷达多快拍数据，提出了基于稀疏恢复的空时自适应处理方法。发表期刊论文31篇，其中SCI 检索期刊论文20篇，EI 检索期刊论文7篇，中文核心期刊论文4篇。EI 检索会议论文4篇。出版专著1 部。培养青年教师1名，博士研究生5名、硕士研究生3名。获批国防专利1项，申请国家发明专利4项。完成了相应计算、仿真和分析程序的开发。本项目的研究为解决主杂波区附近慢速目标的检测难题提供一条崭新的技术途径。研究成果对于推动新体制机载雷达地杂波背景下动目标探测技术的发展具有重要的意义，在军事和民用方面均有十分广阔的应用前景。