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An improved de-interleaving algorithm of radar pulses based on SOFM with self-adaptive network topology

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Journal of Systems Engineering and Electronics 2020年第4期31卷 712-721页

作者： JIANG Wen fu xiongjun CHANG Jiayun QIN Rui School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

As a core part of the electronic warfare(EW) system,de-interleaving is used to separate interleaved radar signals. As interleaved radar pulses become more complex and denser, intelligent classification of radar signals has become very important. The self-organizing feature map(SOFM) is an excellent artificial neural network, which has huge advantages in intelligent classification of complex data. However, the de-interleaving process based on SOFM is faced with the problems that the initialization of the map size relies on prior information and the network topology cannot be adaptively adjusted. In this paper, an SOFM with self-adaptive network topology(SANT-SOFM) algorithm is proposed to solve the above problems. The SANT-SOFM algorithm first proposes an adaptive proliferation algorithm to adjust the map size, so that the initialization of the map size is no longer dependent on prior information but is gradually adjusted with the input data. Then,structural optimization algorithms are proposed to gradually optimize the topology of the SOFM network in the iterative process,constructing an optimal SANT. Finally, the optimized SOFM network is used for de-interleaving radar signals. Simulation results show that SANT-SOFM could get excellent performance in complex EW environments and the probability of getting the optimal map size is over 95% in the absence of priori information.

关键词： de-interleaving self-organizing feature map(SOFM) self-adaptive network topology(SANT)

Design of high-performance energy integrator detector for wideband radar

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Journal of Systems Engineering and Electronics 2019年第6期30卷 1110-1118页

作者： CHANG Jiayun fu xiongjun JIANG Wen XIE Min School of Information and Electronics Beijing Institute of Technology

Target detection for wideband radar has recently received extensive attention. The classical energy integrating(EI)detector will always accumulate excess clutter or noise energy,which leads to unacceptable performance deterioration if the detection window is not selected properly. In this paper, an EI detector for the distributed targets in the Gaussian environment is ***, at the stage of preparatory work, the target models are proposed, then, the problem formulation is introduced. Subsequently,in the aspect of optimizing the method of detection window search and the method of threshold setting, the detailed design stages of the proposed detector are provided. furthermore, theoretical analyses show that the proposed detector is easy to hardware implementation, and it does not need the prior knowledge about the spatial distribution of the target scattering centers in practical radar detection application. Finally, the performance assessment conducted by Monte Carlo simulations verifies that the proposed detector outperforms the conventional detectors.

关键词： radar detection distributed target integration detec tor.

Wideband radar detector based on characteristic parameters of echoes

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Journal of Systems Engineering and Electronics 2019年第5期30卷 897-904页

作者： CHANG Jiayun fu xiongjun JIANG Wen XIE Min School of Information and Electronics Beijing Institute of Technology

The statistical characterization of radar range cells with the target signals is much more distinct than that of the range cells with noise-only ***,the quasi-optimal detection principle based on the characteristic parameters of echo signals is adopted to develop a detector of range-spread targets in Gaussian ***,the characteristic parameters of the return signals in the entire range profiles of radar are ***,the clustering analysis of the characteristic parameter matrix is discussed to extract the test statistic of ***,the probabilities of detection and false alarm of the proposed detector are *** analysis shows that the proposed detector does not need the prior knowledge about the spatial distribution of the target scattering centers in practical scenarios,and it is simple and robust even in low signal-to-noise ratio(low-SNR)*** Carlo(MC)simulations reveal that the detection performance of the proposed detector outperforms the conventional detectors.

关键词： wideband radar mathematical statistics characteristic parameter clustering analysis

Micro-Doppler Parameter Estimation Method Based on Compressed Sensing

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Journal of Beijing Institute of Technology 2019年第2期28卷 286-295页

作者： Jiayun Chang xiongjun fu Wen Jiang Min Xie School of Information and Electronics Beijing Institute of Technology

A micro-Doppler parameter estimation method based on compressed sensing theory is proposed in this *** micro-Doppler parameter estimation algorithm was improved for micro-motion targets with translation in this *** ideal micro-Doppler parameter estimation results were *** proposed micro-Doppler parameter estimation was compared with the traditional micro-Doppler parameter estimation *** for return signal length were analyzed with this new algorithm and its performance was also analyzed in various environments with different SNR.

关键词： feature extraction compressed sensing micro-Doppler parameter estimation

Scheduling Optimization of Space Object Observations for Radar

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Journal of Beijing Institute of Technology 2018年第1期27卷 36-42页

作者： xiongjun fu Liping Wu Chengyan Zhang Min Xie School of Information and Electronics Beijing Institute of Technology

An optimizing method of observation scheduling based on time-division multiplexing is proposed in this paper,and its efficiency is verified by outdoor experiments. The initial observation scheduling is first obtained by using a semi-random search algorithm,and secondly the connection time pair（ CTP） between adjacent objects is optimized by using a genetic algorithm. After obtaining these two parameters,the final observation scheduling can be obtained. According to pre-designed tracks between each adjacent objects in observation order,the seamless observation of neighboring targets is derived by automatically steering the antenna beam,so the observation efficiency is improved.

关键词： space objects observation scheduling semi-random search genetic algorithm

Chaff Jamming Recognition of Radar

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Journal of Beijing Institute of Technology 2018年第1期27卷 43-50页

作者： Min Xie Shuang Zhao xiongjun fu Tianyu Zhang Kaiqiang Liu School of Information and Electronics Beijing Institute of Technology

A modified chaff jamming recognition method of radar is investigated using grey relational analysis（ GRA） based on the difference in echo correlation characteristics between a complex rigid target and chaff cloud in time domain. Slice method（ SM）,a novel modeling approach,is proposed to construct an electromagnetic scattering model of chaff cloud in a scenario with slowly moving platform that is targeted. The diffusion characteristics and echo characteristics of the chaff cloud are analyzed. The GRA of a real target and chaff cloud shows that the adjacent return waves have a good correlation for the target but a weak correlation for chaff cloud. Since the correlation degree of chaff cloud＇s echo is far lower than that of a complex rigid target＇s,the chaff jamming can be identified by setting a reasonable threshold. Simulation results are presented to verify the effectiveness of this method.

关键词： chaff jamming anti-jamming grey relational analysis radar

基于改进fuzzy ART的自适应雷达信号分选

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北京理工大学学报 2024年第9期44卷 990-996页

作者：马志峰张越董健傅雄军北京理工大学集成电路与电子学院北京100081

侦察接收机对获取的辐射源波形去交织以分离不同信号,称为信号分选,是电磁频谱战系统的核心技术.复杂电磁环境下脉冲流密度大、时域波形及诸域特征严重交叠,导致多数基于无监督模型的信号分选方法难以胜任.提出一种可自适应调整警戒阈... 详细信息

侦察接收机对获取的辐射源波形去交织以分离不同信号,称为信号分选,是电磁频谱战系统的核心技术.复杂电磁环境下脉冲流密度大、时域波形及诸域特征严重交叠,导致多数基于无监督模型的信号分选方法难以胜任.提出一种可自适应调整警戒阈值的模糊自适应共振理论(AVT fuzzy ART)聚类算法,基于对属性差异敏感的曼哈顿距离自适应调整警戒阈值,依据在线累积数据得出的辐射源瞬态聚类概率对警戒阈值动态加权.仿真结果表明,该方法能在无历史先验信息的条件下胜任多类别辐射源信号去交错.

关键词：电磁频谱战雷达信号分选模糊自适应共振聚类

间接同步连续采样模式双基地ISAR时间同步仿真

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数据采集与处理 2011年第3期26卷 347-355页

作者：董健尚朝轩高梅国傅雄军中国人民解放军军械工程学院雷达工程教研室石家庄050003 北京理工大学雷达技术研究所北京100081

研究了间接同步连续采样模式下双基地ISAR的时间同步问题。首先分析了双基地ISAR时间系统的特点,建立了间接同步连续采样模式双基地ISAR的时间模型,将其表示为由快时间、慢时间、时间同步误差描述的时间结构。基于该模型,分析了连续采... 详细信息

研究了间接同步连续采样模式下双基地ISAR的时间同步问题。首先分析了双基地ISAR时间系统的特点,建立了间接同步连续采样模式双基地ISAR的时间模型,将其表示为由快时间、慢时间、时间同步误差描述的时间结构。基于该模型,分析了连续采样对双基地ISAR成像的影响,研究了时钟非理想因素对回波相位及成像的影响,并进行了仿真。仿真结果表明,间接同步连续采样不影响回波二维压缩,有较高的时钟非理想因素容限,可以较好地解决双基地ISAR的时间同步问题。

关键词：逆合成孔径雷达双基地时间同步连续采样间接同步

基于改进SAMP的频率捷变和PRI抖动雷达群目标检测

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北京理工大学学报 2023年第1期43卷 87-93页

作者：杜慧茜高浩东傅雄军郎平董健北京理工大学集成电路与电子学院北京100081 陆军工程大学石家庄校区河北石家庄050005

针对群目标场景下目标个数未知和网格失配影响稀疏重构效果的问题,提出一种改进的稀疏度自适应匹配追踪(sparsity adaptive matching pursuit,SAMP)算法用于频率捷变和脉冲重复间隔(pulse repetition interval,PRI)抖动雷达的动目标检测... 详细信息

针对群目标场景下目标个数未知和网格失配影响稀疏重构效果的问题,提出一种改进的稀疏度自适应匹配追踪(sparsity adaptive matching pursuit,SAMP)算法用于频率捷变和脉冲重复间隔(pulse repetition interval,PRI)抖动雷达的动目标检测.改进算法回溯阶段的原子选择策略,通过正则化挑选出能量相近的原子进行网格失配矫正,可以有效减小重构误差、抑制重构伪峰.根据重构信号的功率变化率自适应扩展支撑集长度(群目标个数估值),减少算法在同一步长的搜索时间.仿真结果表明,相比于SAMP算法和传统的群目标检测算法,本文改进的算法在提升重构效果的同时也能减小距离和速度测量误差.

关键词：群目标检测频率捷变 PRI抖动 SAMP算法网格失配