闪烁现象下基于微动补偿的旋转叶片参数估计方法

A Method for Parameters Estimation of Rotating Blades Based on Micro-motion Compensation Under Flashing

目标旋转叶片的微动特征对雷达目标识别有重要意义,但当雷达回波中存在强闪烁现象时难以测量微动参数。针对此问题,提出了一种调频连续毫米波雷达在闪烁现象下的微动补偿参数估计方法。首先建立了调频连续波雷达的旋转散射点回波模型,由线积分得到旋转叶片雷达基带回波信号的解析形式,分析了闪烁现象产生机理和特征。然后,考虑到回波信号所具有的周期性脉冲特征,构造了基于周期脉冲模型的微动参数补偿算子对回波信号进行参数补偿。最后,检测补偿后信号能量峰值完成了旋转叶片微动参数的估计。仿真和实测数据的实验结果表明,所提方法在强闪烁现象下对旋转叶片的旋转频率、旋转长度和初始旋转角具有较高的参数估计精度。

The micro-motion signatures of the target’s rotating blades play important roles in radar space target recognition, but it is difficult to measure micro-motion parameters when the radar echo has flashing phenomenon. In order to solve this problem, a novel micro-motion compensation method based on frequency modulated continuous wave millimeter wave radar to estimate the micro-motion parameters under flashing phenomenon is proposed. Firstly, the scattering point model of frequency modulated continuous wave radar echo for the rotating target is established, and the analytical expression of radar baseband echo signal from the rotating blades is obtained by use of line integral, the mathematical mechanism of flashing is analyzed. Secondly, given the fact that the obtained signal is featured by periodical pulse, a parameterized compensation operator based on the periodical pulse model is constructed, and then the echo signal is compensated by the operator. Finally, the micro-motion parameters of rotating blades is estimated by detecting the energy peak value of compensated signal. The experiment results of simulation and experiment data show that the proposed method can accurately extract rotating frequency, length and initial phase of rotating blades and has high accuracy for parameter estimation in the condition of flashing phenomenon.