基于窄带微多普勒调制的锥体目标参数估计

Parameter Estimation of Cone-shaped Target Based on Narrowband Micro-Doppler Modulation

当雷达对锥体目标发射窄带信号时,进动调制会使回波中包含的散射中心瞬时频率发生周期性变化,这种变化可以反映出目标几何尺寸与结构特性,针对此该文提出一种基于窄带微多普勒调制的空间锥体目标参数估计方法。首先对目标散射特性进行分析,推导进动引起的目标散射中心瞬时频率变化公式;然后利用时变自回归模型估计散射中心瞬时频率,并对估计结果进行重新关联以消除其中出现的关联错误;最后根据锥顶和锥底散射中心瞬时频率变化性质,结合目标弹道估计得到目标几何尺寸参数及微动参数。基于电磁计算数据的实验结果验证了该文所提方法的有效性和精确性。

When radar transmits the narrowband signal to the cone-shaped target, the modulation induced by precession causes the periodic change of scattering centers＇ Instantaneous Frequency（IF） contained in echo, which can reflect the target＇s geometry and structure characteristics. Aiming at this, a parameter estimation method for space cone-shaped target is proposed based on narrowband micro-Doppler modulation. First, the scattering properties of the cone-shaped target are analyzed, and the scattering centers＇ IF variation formulas caused by precession are derived. Then, the Time-Varying Auto Regressive（TVAR） model is utilized to estimate the IF variations from the narrowband echoes of the cone-shaped target, and reassociation is implemented to fix the estimation errors. Finally, based on the properties of the IF variations of the top and bottom scattering centers and the trajectory, the target geometry and micro-motion parameters are estimated. Experiments based on the electromagnetic computation data verify the validness and accuracy of the proposed method.