The conventional direct position determination(DPD) algorithm processes all received signals on a single sensor.When sensors have limited computational capabilities or energy storage,it is desirable to distribute th...The conventional direct position determination(DPD) algorithm processes all received signals on a single sensor.When sensors have limited computational capabilities or energy storage,it is desirable to distribute the computation among other sensors.A distributed adaptive DPD(DADPD)algorithm based on diffusion framework is proposed for emitter localization.Unlike the corresponding centralized adaptive DPD(CADPD) algorithm,all but one sensor in the proposed algorithm participate in processing the received signals and estimating the common emitter position,respectively.The computational load and energy consumption on a single sensor in the CADPD algorithm is distributed among other computing sensors in a balanced manner.Exactly the same iterative localization algorithm is carried out in each computing sensor,respectively,and the algorithm in each computing sensor exhibits quite similar convergence behavior.The difference of the localization and tracking performance between the proposed distributed algorithm and the corresponding CADPD algorithm is negligible through simulation evaluations.展开更多
针对传统两步定位法在固定无源单站定位精度不高的问题,提出一种基于角速度先验的固定无源单站直接定位方法 .首先,给出定位场景及辐射源运动模型,根据雷达辐射源脉内、脉间以及空间采样特点,按照快时间、慢时间、快拍构建三维观测信号...针对传统两步定位法在固定无源单站定位精度不高的问题,提出一种基于角速度先验的固定无源单站直接定位方法 .首先,给出定位场景及辐射源运动模型,根据雷达辐射源脉内、脉间以及空间采样特点,按照快时间、慢时间、快拍构建三维观测信号模型.将快时间变换至频域并提取一组最强信号,利用本文提出的空时对称自相关函数(Space Time Symmetric Autocorrelation Function,STSAF),消除影响定位精度的多余相位项;然后,将经上述处理的2次观测信号进行混频,构建定位模型并给出直接定位代价函数;同时,针对性提出一种基于位置选择的MUSIC(MUltiple SIgnal Classification)算法,根据慢时间域包含的距离信息及空间域包含的方位信息,对辐射源横、纵坐标进行搜索,实现对辐射源的直接定位.本文对算法计算复杂度和克拉美罗下界(Cramer-Rao Lower Bound,CRLB)进行了理论推导,分析了影响定位精度的因素,对比所提直接定位方法与传统两步定位法的均方根误差,绘制本文方法的GDOP(Geometric Dilution Of Precision)曲线.展开更多
为了解决多阵列中子空间数据融合(Subspace data fusion,SDF)算法自由度受限于实际阵元数与定位精度低的问题,本文利用非圆(Non⁃circular,NC)信号特性并结合降维(Reduced⁃dimension,RD)搜索思想提出了一种基于降维搜索的子空间数据融合...为了解决多阵列中子空间数据融合(Subspace data fusion,SDF)算法自由度受限于实际阵元数与定位精度低的问题,本文利用非圆(Non⁃circular,NC)信号特性并结合降维(Reduced⁃dimension,RD)搜索思想提出了一种基于降维搜索的子空间数据融合的非圆信号直接定位算法(Reduced⁃dimension subspace data fusion,RD⁃SDF)。该算法首先利用辐射源信号的NC特性扩展空间信息,以获得增大的虚拟阵列孔径,与更多的可识别信源数。但是由于NC相位导致的高维搜索大大增加了算法求解时的复杂度,本文引入RD搜索思想,通过数据重构消除NC相位导致的高维搜索复杂度问题,并结合SDF构造RD融合搜索谱函数。仿真结果表明,相比于传统SDF算法,本文RD⁃SDF算法具有更高的空间自由度和定位精度。此外,RD⁃SDF算法在保证估计性能的同时显著降低了算法复杂度。展开更多
为了解决子空间数据融合(Subspace data fusion,SDF)算法用于未知互耦影响下的分布式多阵列定位时定位精度低的问题,本文结合降维搜索思想提出了一种降互耦维度的子空间数据融合(Reduced mutual coupling dimension subspace data fusio...为了解决子空间数据融合(Subspace data fusion,SDF)算法用于未知互耦影响下的分布式多阵列定位时定位精度低的问题,本文结合降维搜索思想提出了一种降互耦维度的子空间数据融合(Reduced mutual coupling dimension subspace data fusion,RMCD⁃SDF)方法。该方法首先将互耦误差模型引入SDF算法,使其适应于天线阵列受到未知互耦误差影响的场景。在此基础上,为了降低同时搜索所有未知参数带来的超高计算复杂度,本文引入降维搜索思想并构造了RMCD⁃SDF算法谱函数。仿真结果显示,RMCD⁃SDF算法的定位性能在阵列受到未知互耦影响的场景下具有优势,与现有算法相比计算复杂度接近,但是具有更高的定位精度。在10 dB信噪比下本文算法的定位均方根误差相比经典的SDF算法降低了8.67 dB。展开更多
基金supported by the National Natural Science Foundation of China(61101173)
文摘The conventional direct position determination(DPD) algorithm processes all received signals on a single sensor.When sensors have limited computational capabilities or energy storage,it is desirable to distribute the computation among other sensors.A distributed adaptive DPD(DADPD)algorithm based on diffusion framework is proposed for emitter localization.Unlike the corresponding centralized adaptive DPD(CADPD) algorithm,all but one sensor in the proposed algorithm participate in processing the received signals and estimating the common emitter position,respectively.The computational load and energy consumption on a single sensor in the CADPD algorithm is distributed among other computing sensors in a balanced manner.Exactly the same iterative localization algorithm is carried out in each computing sensor,respectively,and the algorithm in each computing sensor exhibits quite similar convergence behavior.The difference of the localization and tracking performance between the proposed distributed algorithm and the corresponding CADPD algorithm is negligible through simulation evaluations.
文摘针对传统两步定位法在固定无源单站定位精度不高的问题,提出一种基于角速度先验的固定无源单站直接定位方法 .首先,给出定位场景及辐射源运动模型,根据雷达辐射源脉内、脉间以及空间采样特点,按照快时间、慢时间、快拍构建三维观测信号模型.将快时间变换至频域并提取一组最强信号,利用本文提出的空时对称自相关函数(Space Time Symmetric Autocorrelation Function,STSAF),消除影响定位精度的多余相位项;然后,将经上述处理的2次观测信号进行混频,构建定位模型并给出直接定位代价函数;同时,针对性提出一种基于位置选择的MUSIC(MUltiple SIgnal Classification)算法,根据慢时间域包含的距离信息及空间域包含的方位信息,对辐射源横、纵坐标进行搜索,实现对辐射源的直接定位.本文对算法计算复杂度和克拉美罗下界(Cramer-Rao Lower Bound,CRLB)进行了理论推导,分析了影响定位精度的因素,对比所提直接定位方法与传统两步定位法的均方根误差,绘制本文方法的GDOP(Geometric Dilution Of Precision)曲线.
文摘为了解决多阵列中子空间数据融合(Subspace data fusion,SDF)算法自由度受限于实际阵元数与定位精度低的问题,本文利用非圆(Non⁃circular,NC)信号特性并结合降维(Reduced⁃dimension,RD)搜索思想提出了一种基于降维搜索的子空间数据融合的非圆信号直接定位算法(Reduced⁃dimension subspace data fusion,RD⁃SDF)。该算法首先利用辐射源信号的NC特性扩展空间信息,以获得增大的虚拟阵列孔径,与更多的可识别信源数。但是由于NC相位导致的高维搜索大大增加了算法求解时的复杂度,本文引入RD搜索思想,通过数据重构消除NC相位导致的高维搜索复杂度问题,并结合SDF构造RD融合搜索谱函数。仿真结果表明,相比于传统SDF算法,本文RD⁃SDF算法具有更高的空间自由度和定位精度。此外,RD⁃SDF算法在保证估计性能的同时显著降低了算法复杂度。