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Underdetermined mixing matrix estimation by comprehensive application of cluster validity indexes

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The Journal of China Universities of Posts and Telecommunications 2020年第6期27卷 73-86页

作者： Wang Chuanchuan Jiang Lin zeng yonghu Wang Liandong State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System Luoyang 471003China

To solve the problem of mixing matrix estimation for underdetermined blind source separation(UBSS)when the number of sources is unknown,this paper proposed a novel mixing matrix estimation method based on average information entropy and cluster validity index(CVI).Firstly,the initial cluster center is selected by using fuzzy C-means(FCM)algorithm and the corresponding membership matrix is obtained,and then the number of clusters is obtained by using the joint decision of CVI and average information entropy index of membership matrix,then multiple cluster number estimation results can be obtained by using multiple ***,according to the results of the number of multiple clusters estimation,the number of radiation sources is determined according to the principle of the subordination of the minority to the *** cluster center vectors obtained from the clustering operation of the estimated number of radiation sources are fused,that is the mixing matrix is estimated based on the degree of similarity of the cluster center *** the source signal is not sufficiently sparse,the time-frequency single source detection processing can be combined with the proposed method to estimate the mixing *** effectiveness of the proposed method is validated by experiments.

关键词： UBSS estimation of the number of radiation sources mixing matrix FCM clustering CVI

Source enumeration method by combining diagonal loading and constructing second-order statistics

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中国邮电高校学报：英文版 2023年第1期30卷 47-55页

作者： Wang Chuanchuan zeng yonghu Wang Liandong Li Zhipeng State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System Luoyang 471003China

A source enumeration method based on diagonal loading of eigenvalues and constructing second-order statistics is proposed,for the case that the antenna array observed signals are overlapped with spatial colored noise,and the number of antennas compared with the number of snapshots meet the requirement of general asymptotic ***,the sample covariance matrix of the observed signals is obtained,the eigenvalues of the sample covariance matrix can be acquired by eigenvalue decomposition,and the eigenvalues are diagonally loaded,and a new formula for calculating the diagonal loading is *** on the diagonal loaded eigenvalues,the difference values are calculated for the adjacent eigenvalues after diagonal loading,and the statistical variance of the difference values is *** this basis,the second-order statistics of the difference values are constructed,and when the second-order statistics are minimized,the corresponding number of sources is *** proposed method has wide applicability,which is suitable for both general asymptotic regime and classical asymptotic system,and is suitable for both white Gaussian noise environment and colored noise *** method makes up for the lack of source enumeration methods in the case of general asymptotic system and colored noise.

关键词： source enumeration general asymptotic regime colored noise diagonal loading second-order statistics

Improved statistical sparse decomposition principle method for underdetermined blind source signal recovery

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The Journal of China Universities of Posts and Telecommunications 2019年第6期26卷 94-102页

作者： Wang Chuanchuan zeng yonghu Wang Liandong Fu Weihong State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System Luoyang 471003China State Key Laboratory of Integrated Services Networks Xidian UniversityXi'an 710071China

Aiming at the statistical sparse decomposition principle(SSDP) method for underdetermined blind source signal recovery with problem of requiring the number of active signals equal to that of the observed signals, which leading to the application bound of SSDP is very finite, an improved SSDP(ISSDP) method is proposed. Based on the principle of recovering the source signals by minimizing the correlation coefficients within a fixed time interval, the selection method of mixing matrix’s column vectors used for signal recovery is modified, which enables the choose of mixing matrix’s column vectors according to the number of active source signals self-adaptively. By simulation experiments, the proposed method is validated. The proposed method is applicable to the case where the number of active signals is equal to or less than that of observed signals, which is a new way for underdetermined blind source signal recovery.

关键词： underdetermined blind source separation signal recovery ISSDP

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多约束条件下导弹制导控制一体化设计

战术导弹技术 2024年第1期 132-140,149页

作者：张宽桥王川川曾勇虎戚宗锋梁雪娇电子信息系统复杂电磁环境效应国家重点实验室洛阳471003

为增大导弹战斗部毁伤效能,同时保证结构安全和飞行稳定性,基于固定时间稳定性理论和反演滑模控制,提出了一种考虑攻击角度约束、状态约束和控制受限的多约束制导控制一体化设计方法。在纵向平面内构建了带攻击角度约束的制导控制一体... 详细信息

为增大导弹战斗部毁伤效能,同时保证结构安全和飞行稳定性,基于固定时间稳定性理论和反演滑模控制,提出了一种考虑攻击角度约束、状态约束和控制受限的多约束制导控制一体化设计方法。在纵向平面内构建了带攻击角度约束的制导控制一体化设计模型,将目标机动、系统扰动、建模误差等看作未知有界干扰,采用固定时间收敛的滑模干扰观测器估计和补偿干扰。构建了严格固定时间收敛的非奇异终端滑模面,解决攻击角度约束问题。利用二阶指令滤波器约束系统状态和控制指令,构建一种辅助系统补偿滤波器跟踪误差。利用李雅普诺夫稳定性理论,严格证明了闭环系统的固定时间收敛特性。最后,通过对比仿真验证了所提制导控制一体化算法的有效性和优越性。

关键词：制导控制一体化攻击角度约束状态约束控制受限反演控制固定时间收敛

Experimental Research of Dual-Polarization Passive Radar Based on DTTB Signal

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Journal of Computer and Communications 2016年第3期4卷 101-107页

作者： yonghu zeng Xiaofeng Ai Liandong Wang Xiaoyang Wang Guangyong Zheng State Key Laboratory of Complex Electromagnetic Environmental Effects on Electronics and Information System Luoyang 471003 China National University of Defense Technology State Key Laboratory of Complex Electromagnetic Environmental Effects on Electronics and Information System Changsha 410073 China

The passive radar is a hot research topic. A multi-channel wideband passive radar experimental system is designed and the digital television terrestrial broadcasting (DTTB) signal is chosen to carry out the target detection experiment of civil aviation aircraft. The polarization and spatial filtering methods are used to solve the strong direct path interference suppression problems brought by the receiving system location;combined with the characteristics of DTTB signal, the block length selection interval in the block batch processing method for range-Doppler images calculation is given;the clutter suppression performance is compared through the experimental data receiving from different bistatic polarization channels, the conclusion is different from the monostatic radar and it can guide the passive radar experiment.

关键词： Passive Radar Clutter Suppression Block Batch Processing Dual-Polarization

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对成像雷达的间歇采样非均匀转发干扰方法

国防科技大学学报 2019年第2期41卷 132-137页

作者：高磊曾勇虎汪连栋王伟电子信息系统复杂电磁环境效应国家重点实验室河南洛阳471003 国防科技大学电子科学学院湖南长沙410073

间歇采样转发干扰是针对宽带成像雷达的一种有效干扰方式。根据间歇采样转发干扰的基本原理,对宽带成像雷达,按照常规的均匀转发方式,能够在高分辨距离像结果中叠加一串位置均匀分布的虚假散射点。虚假散射点序列的均匀分布特点不利于... 详细信息

间歇采样转发干扰是针对宽带成像雷达的一种有效干扰方式。根据间歇采样转发干扰的基本原理,对宽带成像雷达,按照常规的均匀转发方式,能够在高分辨距离像结果中叠加一串位置均匀分布的虚假散射点。虚假散射点序列的均匀分布特点不利于干扰信号的伪装。针对此问题,以破坏虚假散射点序列均匀分布为目的,在常规间歇采样转发干扰方法基础上,提出间歇采样非均匀转发干扰方法,并分析其干扰效果。最后通过仿真实验验证了所提出的方法能提高对宽带成像雷达的干扰效果。

关键词：间歇采样转发干扰成像雷达非均匀转发

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脉冲激励混响室测试区域电磁场均匀性

强激光与粒子束 2015年第10期27卷 94-99页

作者：贾锐曾勇虎王川川电子信息系统复杂电磁环境效应国家重点实验室河南洛阳471003

研究了电磁脉冲激励混响室内电磁波传播规律,通过仿真建模和实验两方面对脉冲激励混响室测试区域内电磁场均匀性进行了研究。提出了混响室时域均匀性的概念及其计算方法,并利用此方法计算了仿真和实验结果。结果表明:脉冲激励混响室内... 详细信息

研究了电磁脉冲激励混响室内电磁波传播规律,通过仿真建模和实验两方面对脉冲激励混响室测试区域内电磁场均匀性进行了研究。提出了混响室时域均匀性的概念及其计算方法,并利用此方法计算了仿真和实验结果。结果表明:脉冲激励混响室内电磁环境无论在时域上还是频域上,均满足国际标准规定的均匀性要求;在一定空间内,混响室内也可以形成统计平均的脉冲场电磁环境;在混响室内进行电磁脉冲场的电磁敏感度测试是可行的。

关键词：混响室电磁脉冲时域均匀性测试区域

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空中非合作目标旋转部件位置估计方法

国防科技大学学报 2019年第5期41卷 111-117页

作者：高磊曾勇虎汪连栋王伟电子信息系统复杂电磁环境效应国家重点实验室河南洛阳471003 中山大学电子与通信工程学院广东广州510006

针对当前空中非合作目标中旋转部件位置估计方法稳健性不足的问题,在分析旋转部件在高分辨距离像和逆合成孔径雷达像中分布特性的基础上,提出应用逆合成孔径雷达像的方位向距离单元熵和局部径向距离单元熵的旋转部件位置估计方法。该方... 详细信息

针对当前空中非合作目标中旋转部件位置估计方法稳健性不足的问题,在分析旋转部件在高分辨距离像和逆合成孔径雷达像中分布特性的基础上,提出应用逆合成孔径雷达像的方位向距离单元熵和局部径向距离单元熵的旋转部件位置估计方法。该方法能够提升空中非合作目标逆合成孔径雷达成像过程中旋转部件信号分离的准确度。仿真数据和实测数据处理结果证明了所提方法的有效性,通过在实测数据中叠加额外噪声,进一步检验了所提方法对噪声的稳健性。

关键词：逆合成孔径雷达旋转部件高分辨距离像位置估计

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导弹目标单、双基地雷达散射截面对比分析

强激光与粒子束 2018年第1期30卷 62-68页

作者：高磊曾勇虎汪连栋电子信息系统复杂电磁环境效应国家重点实验室河南洛阳471003

目标单、双基地雷达散射截面(RCS)反映了目标是否容易被单、双基地雷达检测到。目前缺乏单、双基地RCS对比的量化指标。首先定义了双基地RCS相对于单基地RCS的RCS增强因子和RCS增强率,然后应用该定义统计分析了某隐身目标和非隐身目标... 详细信息

目标单、双基地雷达散射截面(RCS)反映了目标是否容易被单、双基地雷达检测到。目前缺乏单、双基地RCS对比的量化指标。首先定义了双基地RCS相对于单基地RCS的RCS增强因子和RCS增强率,然后应用该定义统计分析了某隐身目标和非隐身目标双基地RCS计算结果。结果显示:对隐身目标,RCS增强因子大,RCS增强率高,对于非隐身目标,其RCS增强因子显著下降,RCS增强率不高。结合指标含义,应用双基地RCS有助于隐身目标检测,而对非隐身目标效果并不明显,这与雷达界认识相一致。这也说明,应用上述两个指标进行单、双基地RCS对比分析是有效的。此外根据隐身目标在较窄双基地角范围内的双基地RCS分析结果,应用双基地角20°~40°范围内的双基地RCS即可提高对隐身目标的检测效果。

关键词：雷达散射截面增强因子增强率隐身目标