目标近场电磁散射中心建模与特征参数反演

Modeling and Parameter Inversion of Near-fieldElectromagnetic Scattering Center of Targe

摘要:

为了通过较少散射场数据实现雷达目标特性建模和参数反演,提出了一种基于时频图多普勒特征的散射中心建模和特征参数反演方法,采用单频点下的一维角度近场扫描数据实现对目标二维散射中心的提取。通过平滑伪Wigner-Ville分布(smooth and pseudoWigner-Ville distribution,SPWVD)分析方法生成高分辨率时频图,根据不同类型散射中心的多普勒特征,通过Radon逆变换(inverse Radon transform,IRT)提取散射中心模型的位置和幅度参数,并将提取的散射中心位置参数与几何模型参数、散射中心模型重构雷达散射截面积(RCS)与仿真的RCS进行了性能对比。结果表明:该方法只需要单频点的一维角度扫描数据,即可有效提取目标散射中心位置和幅度等特征参数,且重构RCS的均方根误差小于3 dBsm。

Abstract:

To realize radar target characteristic modeling and parameter inversion withless scattering data, a scattering center modeling and parameter inversion method wasproposed based on Doppler characteristics of time-frequency image. The 2D scattering centerwas extracted from near-field 1D angle scanning data at single frequency. Smooth and pseudoWigner-Ville distribution (SPWVD) analysis method was used to generate high resolutiontime-frequency image. The Doppler characteristics of scattering centers were analyzed toestimate position and amplitude parameters of the scattering center model by inverse Radontransform (IRT). Then the scattering center position parameter was compared with thegeometric model parameters, the rebuilt radar cross section (RCS) of the scattering centerwas compared with the RCS obtained by simulation. The simulation results show that theproposed method can extract position and amplitude parameters of scattering center effectively from 1D angle scanning data at single frequency, the root-mean-error of thereconstructed RCS is less than 3 dBsm.