由于共形载体曲率的影响,锥面共形阵列中的阵元不仅具有不同指向的方向图,而且具有不同的极化特性,从而使得共形阵列呈现多极化特性。利用锥面共形阵列的多极化特性,针对现有共形阵列下空间超分辨算法对信号极化参数估计缺失这一问题,...由于共形载体曲率的影响,锥面共形阵列中的阵元不仅具有不同指向的方向图,而且具有不同的极化特性,从而使得共形阵列呈现多极化特性。利用锥面共形阵列的多极化特性,针对现有共形阵列下空间超分辨算法对信号极化参数估计缺失这一问题,结合多重信号分类(multiple signal classification,MUSIC)算法实现了入射信号的极化参数与二维波达方向(direction of arrival,DOA)的联合估计。算法对阵列形式无特殊要求,不需要参数配对;在此基础上进一步对算法的估计性能进行了理论分析与推导,给出了算法多参数估计的克拉美-罗边界(Cramer-Rao bound,CRB)。最后通过计算机仿真验证了算法的有效性。展开更多
This paper studies the estimation performance of the coherent processing parameter （CPP）, including time delay differences and phase synchronization errors among different apertures of the distributed coherent apert...This paper studies the estimation performance of the coherent processing parameter （CPP）, including time delay differences and phase synchronization errors among different apertures of the distributed coherent aperture radar （DCAR）. Firstly, three architectures of signal processing in the DCAR are introduced. Secondly, the closed-form Cramer-Rao bound （CRB） of the CPP estimation is derived and compared. Then, the closed-form CRB is verified by numerical simulations. Finally, when the next generation radar works in a fully coherent mode, the closed-form signal-to-noise ratio （SNR） gain of the three architectures is presented.展开更多
The optimal estimation performance of target parameters is studied. First, the general form of Cramer-Rao bound （CRB） for joint estimation of target location and velocity is derived for coherent multiple input multi...The optimal estimation performance of target parameters is studied. First, the general form of Cramer-Rao bound （CRB） for joint estimation of target location and velocity is derived for coherent multiple input multiple output （MIMO） radars. To gain some insight into the behavior of the CRB, the CRB with a set of given orthogonal waveforms is studied as a specific case. Second, a maximum likelihood （ML） estimation algorithm is proposed. The mean square error （MSE） of the ML estimation of target location and velocity is obtained by Monte Carlo simulation and it approaches CRB in the high signal-to-noise ratio （SNR） region.展开更多
针对宽带信号频域波达方向(direction of arrivals,DOA)估计方法在各子频带能量存在差异时性能下降的问题,提出一种基于归一化克拉美-罗界(Cramer-Rao bound,CRB)加权宽带DOA估计方法。首先在各子频带分别计算DOA估计值,然后根据信号在...针对宽带信号频域波达方向(direction of arrivals,DOA)估计方法在各子频带能量存在差异时性能下降的问题,提出一种基于归一化克拉美-罗界(Cramer-Rao bound,CRB)加权宽带DOA估计方法。首先在各子频带分别计算DOA估计值,然后根据信号在各子频带的归一化克拉美罗界值,对相应子频带的DOA估计值进行加权,从而提高DOA估计精度以及分辨率。仿真实验验证了所提方法的有效性。展开更多
该文研究基于声传感器阵列的单快拍气流速度估计问题。首先,根据声波在亚音速和超音速气流中的传播特性,针对特定的测量装置,建立了声传感器线性阵列的输出模型。在此基础上,提出一种稀疏协方差矩阵迭代的单快拍(Sparse Covariance Matr...该文研究基于声传感器阵列的单快拍气流速度估计问题。首先,根据声波在亚音速和超音速气流中的传播特性,针对特定的测量装置,建立了声传感器线性阵列的输出模型。在此基础上,提出一种稀疏协方差矩阵迭代的单快拍(Sparse Covariance Matrix Iteration with a Single Snapshot,SCMISS)气流速度估计算法,与其他稀疏估计方法相比,该文提出的SCMISS算法无需正则化参数选择,计算量更低,具有更强的实时性,且只需单快拍采样数据就可对亚音速和超音速气流速度进行统一估计。最后,为了评价所提算法的估计性能,推导了气流速度估计的克拉美-罗界(Cramér-Rao Bound,CRB)表达式。仿真实验验证了该算法的有效性。展开更多
The antenna geometry strategy for direction finding （DF） with multiple-input multiple-output （MIMO） radars is studied. One case, usually encountered is practical applications, is consi- dered. For a directional an...The antenna geometry strategy for direction finding （DF） with multiple-input multiple-output （MIMO） radars is studied. One case, usually encountered is practical applications, is consi- dered. For a directional antenna geometry with a prior direction, the trace-optimal （TO） criterion （minimizing the trace） on the av- erage Cramer-Rao bound （CRB） matrix is employed. A qualitative explanation for antenna geometry is provided, which is a combi- natorial optimization problem. In the numerical example section, it is shown that the antenna geometries, designed by the proposed strategy, outperform the representative DF antenna geometries.展开更多
文摘由于共形载体曲率的影响,锥面共形阵列中的阵元不仅具有不同指向的方向图,而且具有不同的极化特性,从而使得共形阵列呈现多极化特性。利用锥面共形阵列的多极化特性,针对现有共形阵列下空间超分辨算法对信号极化参数估计缺失这一问题,结合多重信号分类(multiple signal classification,MUSIC)算法实现了入射信号的极化参数与二维波达方向(direction of arrival,DOA)的联合估计。算法对阵列形式无特殊要求,不需要参数配对;在此基础上进一步对算法的估计性能进行了理论分析与推导,给出了算法多参数估计的克拉美-罗边界(Cramer-Rao bound,CRB)。最后通过计算机仿真验证了算法的有效性。
基金supported by the National Natural Science Foundation of China(61171120)the Key National Ministry Foundation of China(9140A07020212JW0101)+2 种基金the Foundation of Tsinghua University(20101081772)the Foundation of National Laboratory of Information Control Technology for Communication System of Chinathe Foundation of National Information Control Laboratory
文摘This paper studies the estimation performance of the coherent processing parameter （CPP）, including time delay differences and phase synchronization errors among different apertures of the distributed coherent aperture radar （DCAR）. Firstly, three architectures of signal processing in the DCAR are introduced. Secondly, the closed-form Cramer-Rao bound （CRB） of the CPP estimation is derived and compared. Then, the closed-form CRB is verified by numerical simulations. Finally, when the next generation radar works in a fully coherent mode, the closed-form signal-to-noise ratio （SNR） gain of the three architectures is presented.
基金supported by the National Natural Science Foundation of China(61171120)the Key National Ministry Foundation of China(9140A07020212JW0101)the Foundation of Tsinghua University(20101081772)
文摘The optimal estimation performance of target parameters is studied. First, the general form of Cramer-Rao bound （CRB） for joint estimation of target location and velocity is derived for coherent multiple input multiple output （MIMO） radars. To gain some insight into the behavior of the CRB, the CRB with a set of given orthogonal waveforms is studied as a specific case. Second, a maximum likelihood （ML） estimation algorithm is proposed. The mean square error （MSE） of the ML estimation of target location and velocity is obtained by Monte Carlo simulation and it approaches CRB in the high signal-to-noise ratio （SNR） region.
文摘针对宽带信号频域波达方向(direction of arrivals,DOA)估计方法在各子频带能量存在差异时性能下降的问题,提出一种基于归一化克拉美-罗界(Cramer-Rao bound,CRB)加权宽带DOA估计方法。首先在各子频带分别计算DOA估计值,然后根据信号在各子频带的归一化克拉美罗界值,对相应子频带的DOA估计值进行加权,从而提高DOA估计精度以及分辨率。仿真实验验证了所提方法的有效性。
文摘该文研究基于声传感器阵列的单快拍气流速度估计问题。首先,根据声波在亚音速和超音速气流中的传播特性,针对特定的测量装置,建立了声传感器线性阵列的输出模型。在此基础上,提出一种稀疏协方差矩阵迭代的单快拍(Sparse Covariance Matrix Iteration with a Single Snapshot,SCMISS)气流速度估计算法,与其他稀疏估计方法相比,该文提出的SCMISS算法无需正则化参数选择,计算量更低,具有更强的实时性,且只需单快拍采样数据就可对亚音速和超音速气流速度进行统一估计。最后,为了评价所提算法的估计性能,推导了气流速度估计的克拉美-罗界(Cramér-Rao Bound,CRB)表达式。仿真实验验证了该算法的有效性。
基金supported by the National Natural Science Foundation of China(6107211761302142)
文摘The antenna geometry strategy for direction finding （DF） with multiple-input multiple-output （MIMO） radars is studied. One case, usually encountered is practical applications, is consi- dered. For a directional antenna geometry with a prior direction, the trace-optimal （TO） criterion （minimizing the trace） on the av- erage Cramer-Rao bound （CRB） matrix is employed. A qualitative explanation for antenna geometry is provided, which is a combi- natorial optimization problem. In the numerical example section, it is shown that the antenna geometries, designed by the proposed strategy, outperform the representative DF antenna geometries.
