针对低信噪比条件下,传统的基于旋转不变技术的三维信号参数估计(three-dimensional estimating signal parameter via rotational invariance te chniques,3D-ESPRIT)算法和平方前后向平滑的3D-ESPRIT(quadr atic-forward-backward 3D-...针对低信噪比条件下,传统的基于旋转不变技术的三维信号参数估计(three-dimensional estimating signal parameter via rotational invariance te chniques,3D-ESPRIT)算法和平方前后向平滑的3D-ESPRIT(quadr atic-forward-backward 3D-ESPRIT,Q-FB-3D-ESPRIT)算法对几何绕射理论(geometric theory of diffraction,GTD)模型参数估计精度显著降低的问题,提出改进的极化Q-FB-3D-ESPRIT(polarized-Q-FB-3D-ESPRIT,PQ-FB-3D-ESPRIT)算法。改进算法与上述两种传统算法相比,增加了对目标极化信息的利用,有效延长了可利用电磁散射数据的长度。仿真结果表明,改进算法的参数估计精度要高于其他两种算法,且在低信噪比情况下尤为显著。此外,还对基于散射中心模型的雷达目标识别进行了研究,仿真结果进一步验证了所提算法的可行性。展开更多
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,2...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。展开更多
An online pulse interleaving scheduling algorithm is proposed for a solution to the task scheduling problem in the digital array radar(DAR). The full DAR task structure is explicitly considered in a way that the waiti...An online pulse interleaving scheduling algorithm is proposed for a solution to the task scheduling problem in the digital array radar(DAR). The full DAR task structure is explicitly considered in a way that the waiting duration is able to be utilized to transmit or receive subtasks, namely the pulse interleaving,as well as the receiving durations of different tasks are able to be overlapped. The algorithm decomposes the pulse interleaving scheduling analysis into the time constraint check and the energy constraint check, and schedules online all kinds of tasks that are able to be interleaved. Thereby the waiting duration and the receiving duration in the DAR task are both fully utilized. The simulation results verify the performance improvement and the high efficiency of the proposed algorithm compared with the existing ones.展开更多
The noise robustness and parameter estimation performance of the classical three-dimensional estimating signal parameter via rotational invariance techniques(3D-ESPRIT)algorithm are poor when the parameters of the geo...The noise robustness and parameter estimation performance of the classical three-dimensional estimating signal parameter via rotational invariance techniques(3D-ESPRIT)algorithm are poor when the parameters of the geometric theory of the diffraction(GTD)model are estimated at low signal-to-noise ratio(SNR).To solve this problem,a modified 3D-ESPRIT algorithm is proposed.The modified algorithm improves the parameter estimation accuracy by proposing a novel spatial smoothing technique.Firstly,we make cross-correlation of the auto-correlation matrices;then by averaging the cross-correlation matrices of the forward and backward spatial smoothing,we can obtain a novel equivalent spatial smoothing matrix.The formula of the modified algorithm is derived and the performance of this improved method is also analyzed.Then we compare root-meansquare-errors(RMSEs)of different parameters and the locating accuracy obtained by different algorithms.Furthermore,radar cross section(RCS)of radar targets is extrapolated.Simulation results verify the effectiveness and superiority of the modified 3DESPRIT algorithm.展开更多
文摘针对低信噪比条件下,传统的基于旋转不变技术的三维信号参数估计(three-dimensional estimating signal parameter via rotational invariance te chniques,3D-ESPRIT)算法和平方前后向平滑的3D-ESPRIT(quadr atic-forward-backward 3D-ESPRIT,Q-FB-3D-ESPRIT)算法对几何绕射理论(geometric theory of diffraction,GTD)模型参数估计精度显著降低的问题,提出改进的极化Q-FB-3D-ESPRIT(polarized-Q-FB-3D-ESPRIT,PQ-FB-3D-ESPRIT)算法。改进算法与上述两种传统算法相比,增加了对目标极化信息的利用,有效延长了可利用电磁散射数据的长度。仿真结果表明,改进算法的参数估计精度要高于其他两种算法,且在低信噪比情况下尤为显著。此外,还对基于散射中心模型的雷达目标识别进行了研究,仿真结果进一步验证了所提算法的可行性。
文摘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。
文摘An online pulse interleaving scheduling algorithm is proposed for a solution to the task scheduling problem in the digital array radar(DAR). The full DAR task structure is explicitly considered in a way that the waiting duration is able to be utilized to transmit or receive subtasks, namely the pulse interleaving,as well as the receiving durations of different tasks are able to be overlapped. The algorithm decomposes the pulse interleaving scheduling analysis into the time constraint check and the energy constraint check, and schedules online all kinds of tasks that are able to be interleaved. Thereby the waiting duration and the receiving duration in the DAR task are both fully utilized. The simulation results verify the performance improvement and the high efficiency of the proposed algorithm compared with the existing ones.
基金This work was supported by the National Natural Science Foundation of China(61372033).
文摘The noise robustness and parameter estimation performance of the classical three-dimensional estimating signal parameter via rotational invariance techniques(3D-ESPRIT)algorithm are poor when the parameters of the geometric theory of the diffraction(GTD)model are estimated at low signal-to-noise ratio(SNR).To solve this problem,a modified 3D-ESPRIT algorithm is proposed.The modified algorithm improves the parameter estimation accuracy by proposing a novel spatial smoothing technique.Firstly,we make cross-correlation of the auto-correlation matrices;then by averaging the cross-correlation matrices of the forward and backward spatial smoothing,we can obtain a novel equivalent spatial smoothing matrix.The formula of the modified algorithm is derived and the performance of this improved method is also analyzed.Then we compare root-meansquare-errors(RMSEs)of different parameters and the locating accuracy obtained by different algorithms.Furthermore,radar cross section(RCS)of radar targets is extrapolated.Simulation results verify the effectiveness and superiority of the modified 3DESPRIT algorithm.