摘要
二维基于旋转不变技术信号参数估计(2D-estimating signal parameter via rotational invariance techniques,2D-ESPRIT)算法是估计几何绕射理论(geometric theory of diffraction,GTD)模型参数的一种经典算法,但在信噪比较低的条件下,2D-ESPRIT算法的参数估计精度明显下降,噪声鲁棒性较差。针对这一问题,提出一种极化平方前后向平滑2D-ESPRIT(polarized-quadratic-forward-backward 2D-ESPRIT,PQ-FB-2D-ESPRIT)算法,有效地提高了算法的噪声鲁棒性与参数估计性能。改进算法利用目标散射回波数据的极化信息,并通过对协方差矩阵平方处理和前后向空间平滑处理,提高了算法的参数估计性能与数据利用率,同时达到了去相关的效果。仿真结果表明,提出的PQ-FB-2D-ESPRIT算法的参数估计性能及噪声鲁棒性要优于经典2D-ESPRIT算法、前后向平滑2D-ESPRIT(forward-backward 2D-ESPRIT,FB-2D-ESPRIT)算法及平方FB-2D-ESPRIT(quadraticFB-2D-ESPRIT,Q-FB-2D-ESPRIT)算法。基于不同算法估计得到的GTD模型参数对散射中心的定位精度进行比较,进一步验证了改进算法的优越性与有效性。
2D-estimating signal parameter via rotational invariance techniques(2D-ESPRIT)is a classical algorithm to estimate parameters of the two dimensional(2D)geometric theory of diffraction(GTD)model.However,the parameter estimation accuracy and noise robustness of 2D-ESPRIT are poor as signal-to-noise ratio(SNR)decreases.To solve the problem,apolarized-quadratic-forward-backward-2D-ESPRIT(PQ-FB-2D-ESPRIT)algorithm is proposed,which improves noise robustness and parameter estimation performance effectively.The improved algorithm makes full use of the polarization information of radar targets,squares the covariance matrix and performs forward-backward smoothing on the novel covariance matrix.Therefore,the parameter estimation performance and data utilization are improved significantly by this improved algorithm.Simulation experiments verify that the proposed PQ-FB-2D-ESPRIT algorithm has a better noise robustness and more stable parameter estimation performance than the classical 2D-ESPRIT algorithm,forward-backward-2DESPRIT(FB-2D-ESPRIT)algorithm and quadratic-FB-2D-ESPRIT(Q-FB-2D-ESPRIT)algorithm.Based on the GTD model parameters estimated by different algorithms,the positioning accuracies of scattering centers are compared,which can validate the superiorty and effectiveness of the proposed algorithm.
作者
郑舒予
张小宽
宗彬锋
徐嘉华
李江
ZHENG Shuyu;ZHANG Xiaokuan;ZONG Binfeng;XU Jiahua;LI Jiang(Air and Missile Defense College of Air Force Engineering University,Xi’an 710051,China;The graduate school of Air Force Engineering University,Xi’an 710051,China)
出处
《系统工程与电子技术》
EI
CSCD
北大核心
2020年第6期1283-1289,共7页
Systems Engineering and Electronics
基金
国家自然科学基金(61701528)
目标与环境电磁散射辐射国防科技重点实验室创新基金(STES201401-1)资助课题。
关键词
参数估计
散射中心
二维GTD模型
2D-ESPRIT算法
共轭矩阵
parameter estimation
scattering center
2D-geometric theory of diffraction(2D-GTD)model
2D-estimation of signal parameters via rotational invariance techniques(2D-ESPRIT)algorithm
conjugate matrix