旋转对称雷达目标的微多普勒特征提取与雷达系统相参性约束

The micro-motion dynamics of targets include spin, coning, vibration, and some composite motions such as precession, nutation, tumbling. The micro-motions could induce micro-Doppler effect. The fine motion characteristics of targets could be obtained by micro-Doppler feature extraction, which provides a novel approach for radar target recognition. Aiming at rotationally symmetrical targets with precession and high-speed translational motion, this project makes deep research on the key issues including coherent motion compensation, precession period estimation, the number of scattering centers with micro-motion and corresponding micro-Doppler magnitude and initial phase estimation, the constraint of radar system coherency. Owing to the requirement of returns' phase correction precision, a coherent motion compensation method is proposed by fitting real track data segmentally. In order to meet the requirement of characteristic parameter estimation precision in automatic target recognition, a sequential micro-Doppler feature extraction approach is presented based on S-Method time-frequency analysis cascaded with inverse Radon transform. This project also makes deep research on the constraint about radar system clock frequency stability. The purpose of this research work is to achieve an effective and practical means to extract micro-Doppler features, and provide theoretical support for the development of micro-Doppler radar system.

目标的微运动包括自旋、锥旋、振动等基本运动，以及进动、章动、翻滚等复合运动。微运动引起微多普勒效应，微多普勒特征提取能获得目标精细的运动特性，为雷达目标识别提供新的技术手段。本项目针对同时作高速平动的旋转对称进动目标，研究了相参平动补偿、进动周期估计、微运动散射中心个数及相应的微多普勒幅度/初相估计、对雷达系统相参性的要求等关键问题。提出航迹测量数据分段拟合的相参运动补偿方法，可满足微多普勒特征提取对回波相位校正精度的要求；提出SM时频分析与逆Radon变换级联的微多普勒特征序贯提取方法，可满足自动目标识别对特征参数估计精度的要求；研究了微多普勒特征提取对雷达系统时钟频率稳定度的需求。研究目标是从实际应用的角度提出行之有效的微多普勒特征提取方法，为微多普勒测量雷达系统的研制提供理论支撑。

目标的微运动会引起微多普勒效应，微多普勒特征反映了目标精细的运动特性，为雷达目标识别提供新的技术手段。本项目针对同时作高速平动的旋转对称进动目标，研究了相参平动补偿、进动周期估计、微运动散射中心个数及相应的微多普勒幅度/初相估计、对雷达系统相参性的要求等关键问题。提出航迹测量数据分段拟合的相参运动补偿方法，可满足微多普勒特征提取对回波相位校正精度的要求；提出SM时频分析与逆Radon变换级联的微多普勒特征序贯提取方法，可满足自动目标识别对特征参数估计精度的要求；研究了微多普勒特征提取对雷达系统时钟频率稳定度的需求。利用雷达采集旋转对称目标的微运动回波进行验证，结果表明了创新方法的有效性。本项目的研究成果可为微多普勒测量雷达系统的研制提供理论支撑。