一种基于时空瞬时稳定性的方位谱估计方法  

An orientation spectrum estimation method based on temporal and spatial instantaneous stability WANG Linsheng1,2,WANG Huiting3,LIU Zhigang4

作　　者：王林生 王慧婷[3] 刘志刚 WANG Linsheng;WANG Huiting;LIU Zhigang(Henan Provincial Engineering Research Center of Industrial Embedded Network Control,Nanyang 473009,China;Henan Polytechic Institute,Nanyang 473009,China;Institute of Science and Technology Development,Beijing University of Posts and Telecommunications,Beijing 100876,China;Lab of Safety Simulation,Nanchang University,Nanchang 330031,China)

机构地区：[1]河南省工业嵌入式网络控制工程技术研究中心,河南南阳473009 [2]河南工业职业技术学院,河南南阳473009 [3]北京邮电大学科学技术发展研究院,北京100876 [4]南昌大学安全仿真模拟实验室,南昌330031

出　　处：《振动与冲击》2021年第13期281-288,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金(41505015);2019年度河南省高等职业学校青年骨干教师培养计划(2019GZGG018)。

摘　　要：针对基于子空间分解的空间方位谱估计方法稳健性问题,提出了一种基于时空瞬时稳定的方位谱估计方法。该方法首先依据空间目标信号时域瞬时稳定性,将协方差矩阵频域求取过程转换为经相参补偿的复域求取,降低空间数据稳定性对协方差矩阵估计的影响;然后依据各子空间输出方位谱峰值索引离散度差异,提取各子空间方位谱加权因子;最后根据加权因子实现对各子空间方位谱加权处理,降低背景噪声对最终合成空间方位谱影响。数值仿真及实测数据处理结果表明,相比子空间分解方法,在不损失空间分辨率情况下,能够有效降低空间数据稳定性对协方差矩阵估计产生的影响,在无目标先验信息情况下,对最低信噪比的需求得到了6 dB以上的降低。Here,aiming at the robustness problem of spatial orientation spectrum estimation method based on subspace decomposition,an orientation spectrum estimation method based on temporal and spatial instantaneous stability was proposed.Firstly,according to the instantaneous stability of space target signal in time domain,the solving process in frequency domain of covariance matrix was converted into its solving process in complex domain by coherent compensation to reduce effects of spatial data stability on covariance matrix estimation.Secondly,according to difference of orientation spectrum peak value index dispersion output by each subspace,the weighting factor of orientation spectrum of each subspace was extracted.Finally,various subspace orientation spectra were weighted with these weighting factors to form the synthetized space orientation spectrum and reduce effects of background noise on the final spectrum.The results of numerical simulation and actual measured data processing showed that compared with the subspace decomposition method,the proposed method can effectively reduce effects of spatial data stability on covariance matrix estimation without loss of spatial resolution;the requirement of the minimum signal-to-noise ratio is reduced by more than 6 dB without target prior information.

关 键 词：方位谱估计 协方差矩阵 复域 峰值索引离散度 加权因子 

分 类 号：TN912[电子电信—通信与信息系统]