Optimization of jamming formation of USV offboard active decoy clusters based on an improved PSO algorithm

Offboard active decoys(OADs)can effectively jam monopulse radars.However,for missiles approaching from a particular direction and distance,the OAD should be placed at a specific location,posing high requirements for timing and deployment.To improve the response speed and jamming effect,a cluster of OADs based on an unmanned surface vehicle(USV)is proposed.The formation of the cluster determines the effectiveness of jamming.First,based on the mechanism of OAD jamming,critical conditions are identified,and a method for assessing the jamming effect is proposed.Then,for the optimization of the cluster formation,a mathematical model is built,and a multi-tribe adaptive particle swarm optimization algorithm based on mutation strategy and Metropolis criterion(3M-APSO)is designed.Finally,the formation optimization problem is solved and analyzed using the 3M-APSO algorithm under specific scenarios.The results show that the improved algorithm has a faster convergence rate and superior performance as compared to the standard Adaptive-PSO algorithm.Compared with a single OAD,the optimal formation of USV-OAD cluster effectively fills the blind area and maximizes the use of jamming resources.

Cross-eye gain distribution of multiple-element retrodirective cross-eye jamming

The total cross-eye gain of multiple-element retrodirective cross-eye jamming(MRCJ) in the presence of the platform skin return is a distribution rather than a constant value, due to the random variation in the phase of the skin return. Although the median value of the total cross-eye gain distribution had been analyzed in previous studies, the extreme values providing useful indications of the upper and lower bounds of the total cross-eye gain have not been analyzed until now. In this paper, the cumulative distribution function and the extreme values of the total cross-eye gain of MRCJ are derived. The angular error induced in threat monopulse radar as a figure of merit is used to analyze the performance of MRCJ system. Simulation results demonstrate the variation of the angular error and discuss the proper value of jamming-to-signal ratio(JSR) making the MRCJ system more effective in consideration of the whole distribution of the total cross-eye gain.

Tolerance analysis of multiple-element linear retrodirective cross-eye jamming

Tolerance sensitivity limits the practical application of the cross-eye jammer.Previous literature has demonstrated that retrodirective cross-eye jamming with multiple antenna elements possesses the advantage of loose tolerance requirements compared to traditional cross-eye jamming.However,the previous analysis was limited,because there are still some factors affecting the parameter tolerance of the multiple-element retrodirective cross-eye jamming(MRCJ)system and they have not been investigated completely,such as the loop difference,the baseline ratio and the jammer-to-signal ratio.This paper performs a comprehensive tolerance analysis of the MRCJ system with a nonuniformspacing linear array.Simulation results demonstrate the tolerance effects of the above influence factors and give reasonable advice for easing tolerance sensitivity.

Deceptive jamming suppression in multistatic radar based on coherent clustering

This paper proposes a suppression method of the deceptive false target(FT) produced by digital radio frequency memory(DRFM) in a multistatic radar system. The simulated deceptive false targets from DRFM cannot be easily discriminated and suppressed with traditional radar systems. Therefore, multistatic radar has attracted considerable interest as it provides improved performance against deception jamming due to several separated receivers. This paper first investigates the received signal model in the presence of multiple false targets in all receivers of the multistatic radar. Then, obtain the propagation time delays of the false targets based on the cross-correlation test of the received signals in different receivers. In doing so, local-density-based spatial clustering of applications with noise(LDBSCAN) is proposed to discriminate the FTs from the physical targets(PTs) after compensating the FTs time delays, where the FTs are approximately coincident with one position, while PTs possess small dispersion.Numerical simulations are carried out to demonstrate the feasibility and validness of the proposed method.

The Intermittent Sampling Motion Scatter Wave Jamming against Waveform Agile SAR/GMTI

A new method jamming against Waveform Agile SAR/GMTI (Ground Moving Target Indication) is proposed, which is called the intermittent sampling motion scatter wave jamming. This jamming can form multi-false vivid targets scene taking the real moving targets’ all scattering information. The intermittent sampling repeater can also repeat in the waveform agile SAR current pulses. As a clever jamming mode, this jamming may realize electronic counter measure (ECM) against wave- form agile SAR. Detailed discussions about the jamming performance are given. The processing output of the jamming is derived theoretically. The superiority of this jamming is analyzed in theory. The theoretical feasibility and validity are proved by simulation experiments.

Noise amplitude modulation jamming signal suppression based on weighted-matching pursuit

To suppress noise amplitude modulation jamming in a single-antenna radar system, a new method based on weighted-matching pursuit （WMP） algorithm is proposed, which can achieve underdetermined blind sources separation of the jamming and the target echo from the jammed mixture in the single channel of the receiver. Firstly, the presented method utilizes a prior information about the differences between the jamming component and the radar transmitted signal to construct two signal-adapted sub-dictionaries and to determine the weights. Then the WMP algorithm is applied to remove the jamming component from the mixture. Experimental results verify the validity of the presented method. By comparison of the pulse compression performance, the simulation results shows that the presented method is superior to the method of frequency domain cancellation （FDC） when the jamming-to-signal ratio （JSR） is lower than 15 dB.

基于时域编码超表面脉内-脉间编码优化的雷达干扰方法

时域编码超表面是一项可以对电磁波进行时变调制的新技术,针对该技术的调控特性,该文提出了一种基于时域编码超表面脉内-脉间编码优化的雷达干扰方法。首先分别在快时间域和慢时间域建立优化模型,通过优化脉内-脉间相位编码,实现目标能量的搬移,形成距离-多普勒二维图上的欺骗干扰。然后通过遗传算法对该离散优化模型进行求解。另外,该文从超表面编码策略的角度分析了多种调控因素对干扰效果的影响,为实现欺骗干扰的最佳策略提供指导。

一种基于时间编码超表面的ISAR干扰方法

时间编码超表面具备对电磁波的调制能力,从而有效改变反射电磁波的特性,达到改变目标特性的目的。基于超表面的调控特性,设计了一种周期时间编码的逆合成孔径雷达(Inverse Synthetic Aperture Radar,ISAR)干扰方法。分析了时间编码超表面的相位调制机理,建立了时间编码序列模型,通过设计优化时间编码序列的相关参数,形成对雷达在距离向上的欺骗干扰。通过理论推导,分析了时间编码调制参数对假目标位置、幅度等的影响。仿真实验结果表明,该方法可以根据信号参数生成数量可控、位置可变的虚假目标,距离向干扰范围扩展至2倍以上,从而实现不同的干扰效果,在电子对抗等方面具有较高的应用价值。

基于脉内频率编码联合调频斜率捷变波形的ISRJ对抗方法

间歇采样转发干扰(ISRJ)是一种脉内相参干扰,能在目标斜距前后形成多个逼真假目标来严重影响雷达检测,是当前电子反对抗的热点之一。针对这一问题,该文提出了一种基于脉内频率编码联合调频斜率捷变波形的抗ISRJ方法。首先,雷达发射脉内频率编码联合调频斜率捷变信号,通过子脉冲中心频率、调频斜率捷变提高子脉冲间相互掩护能力。之后依据发射信号子脉冲斜率变化时序将回波信号划分为多个切片。然后利用模糊C均值(FCM)算法对回波切片进行干扰识别。最后在分数阶域和时域对回波信号进行级联滤波。仿真结果表明,FCM方法在信噪比(SNR)大于-2.5 dB和干信比(JSR)大于5 dB时,能100%识别干扰机同步采样场景下回波中的受干扰回波切片。在较高JSR和低SNR下,所提方法能有效减少目标能量损失并抑制剩余干扰产生的距离旁瓣。在JSR为50 dB时,干扰抑制后的目标检测概率可达90%以上。

基于概率推理的舷外有源诱饵干扰评估方法研究

针对电子对抗的非合作性和传统干扰效能评估方法的主观性,围绕舷外有源诱饵,提出了一种基于概率推理的干扰有效性评估方法。首先,由导弹末段制导动态过程推导干扰有效性判据,从信号层面与态势层面分析非合作参数作用。然后,基于概率推理原理,构建干扰有效性推理模型,阐述了干扰有效性评估内容。最后,通过数值仿真分析了正向推理和反向推理结果,并对不同诱饵干扰策略进行评估。仿真结果表明,利用概率推理可从未知参数中得到干扰有效性判据的概率分布,为舷外有源诱饵提供了量化且可扩展的干扰评估框架。

基于快慢时间平均变化率的SAR欺骗干扰方法研究

对合成孔径雷达(Synthetic Aperture Radar,SAR)实施欺骗干扰,干扰方通常需要预先获取一些关键干扰参数,如SAR载机平台到干扰机的最近斜距、信号调频斜率、中心频率等,获取这些参数通常需要复杂的侦察设备。针对这一问题,提出了一种基于快慢时间平均变化率的SAR欺骗干扰方法。干扰机截获到SAR信号后,通过求解快慢时间的平均变化率,可巧妙获得干扰信号距离向和方位向的调制相位项,从而实现对SAR的欺骗干扰。所提方法仅需SAR信号脉冲重复频率和载机平台速度,有效地解决了需复杂设备侦察上述关键参数的难题,简化了干扰系统的配置。研究表明,所提方法假目标聚焦效果良好,即使平台速度估计存在误差,仅会影响假目标方位向位置误差,对假目标的成像聚焦效果几乎没有影响。

雷达对抗技术研究综述与智能反干扰展望

电磁频谱的争夺是未来信息化战场至关重要的博弈对抗,为了应对更加灵巧和智能化的电子干扰,雷达也必须要发展智能化的反干扰技术。围绕当前雷达反干扰技术发展现状,将雷达反干扰技术框架分解为被动干扰抑制、主动干扰抑制和认知反干扰3个主要模块,从基础原理、实现逻辑、性能表现等方面对近几年的代表性文献进行了归纳总结。在此基础上,引入了干扰记忆诱导的智能化反干扰概念,丰富了雷达反干扰智能化内涵。并进一步分析了未来该领域的技术需求、应对场景以及发展趋势,为后续的反干扰技术智能化发展提供参考和依据。

干扰位置可控的SAR散射波干扰方法

当前对SAR的散射波干扰产生的虚假图像位置较为固定,且受侦察参数误差和环境影响会出现一定偏移,难以准确覆盖在目标区域之上,针对这一难题,本文提出了一种对SAR的散射波干扰进行位置调制,产生位置可控的假目标的方法,此方法结合SAR成像的距离向和方位向两个维度的位置参数进行调制,实验结果表明,与传统对SAR的散射波干扰相比,本文方法产生的干扰图像可以精准覆盖在目标区域之上,使雷达端的成像结果中对真实目标和干扰图像的识别结果被混淆。

宽带雷达组网协同抗欺骗式干扰方法

现代雷达为了实现目标侦察功能,一般会使用相应的电子抗干扰技术,而强大的抗干扰能力则是其在复杂的电磁干扰条件下完成任务的重要保证。现有组网雷达抗干扰技术大多针对窄带组网雷达,而宽带雷达相对于窄带雷达具有更高的分辨率,可以探测目标更加全面的信息,达到更好的抗干扰效果。针对宽带组网雷达下的抗欺骗式干扰方法,现有研究直接类比窄带雷达抗欺骗式干扰方法,假设真实目标在每个距离单元的回波矢量独立同分布,并没有从理论上分析多视角一维距离像去相关的内在原因。针对此问题,本文推导了真实目标的三维散射中心模型投影得到目标多视角一维距离像的过程,并以此为基础,分析了真假目标一维距离像在各雷达站中的差异,及真实目标一维距离像在不同宽带雷达中的同源非一致性与转发式欺骗干扰在不同宽带雷达中的同源一致性。基于此差异,进一步提出了一种在宽带雷达组网条件下,基于一维距离像相关性差异的抗欺骗式干扰方法,设计了鉴别统计量并分析了基于累积分布函数的闭式鉴别性能。计算机仿真结果表明,本文所提方法体系能够有效对抗宽带欺骗式干扰,且鉴别性能相对于目标尺寸来说较为稳健。

雷达电子对抗技术及应用研究

雷达技术在现代军事中具有重要作用。随着科技的不断进步,雷达电子对抗技术逐渐成为军事领域中的热点。随着高新技术不断发展,在未来战争中,信息控制权和空中力量之争势必会将军用雷达作为首选目标实施电子干扰。因此,在雷达干扰和抗干扰方面开展技术学习和研究,可以加强我军信息化建设,在战场上获得主动权。基于此,本文探讨雷达电子对抗技术分析及其应用实践等内容,分别从雷达电子对抗的概述、雷达电子对抗技术分析及其应用实践进行分析。

SE-DEA-SVM evaluation method of ECM operational disposition scheme

Operational disposition of electronic countermeasures(ECM)is a hot topic in modern warfare research.Through fully analyzing the characteristics and shortcomings of the traditional operational disposition scheme,a super-efficient data envelopment analysis support vector machine(SE-DEA-SVM)method for evaluating the operational configuration scheme of ECM is proposed.Firstly,considering the subjective and objective factors affecting the operational disposition of ECM,the index system of operational disposition scheme is established,and we explain the solution method of terminal indexs.Secondly,the evaluation and algorithm process of SE-DEA-SVM evaluation method are introduced.In this method,the super-efficient data envelopment analysis(SE-DEA)model is used to calculate the weight of index system,and the support vector machine(SVM)method combined with the training samples of evaluation index is used to obtain the input-output model of evaluation value of combat configuration.Finally,by an example(obtaining five schemes),we verify the SE-DEA-SVM evaluation method and analyze the results.The efficiency analysis,comparison analysis,and error analysis of this method are carried out.The results show that this method is more suitable for military evaluation with small samples,and it has high efficiency,applicability,and popularization value.

ECCM scheme against interrupted sampling repeater jammer based on time-frequency analysis

The interrupted sampling repeater jamming（ISRJ） is an effective deception jamming method for coherent radar, especially for the wideband linear frequency modulation（LFM） radar. An electronic counter-countermeasure（ECCM） scheme is proposed to remove the ISRJ-based false targets from the pulse compression result of the de-chirping radar. Through the time-frequency（TF） analysis of the radar echo signal, it can be found that the TF characteristics of the ISRJ signal are discontinuous in the pulse duration because the ISRJ jammer needs short durations to receive the radar signal. Based on the discontinuous characteristics a particular band-pass filter can be generated by two alternative approaches to retain the true target signal and suppress the ISRJ signal. The simulation results prove the validity of the proposed ECCM scheme for the ISRJ.

雷达智能博弈抗干扰技术综述与展望

随着认知电子战技术的发展,干扰机电磁对抗能力大幅提升,为有效对抗智能化干扰机,雷达需采取智能博弈抗干扰技术。文中围绕雷达智能博弈抗干扰技术发展现状,从相关理论基础、干扰感知、智能抗干扰策略学习方法、雷达/干扰博弈抗干扰方法梳理相关技术原理和代表性工作,并进一步分析了该领域的发展趋势,为后续理论研究提供必要参考。

一种认知电子战雷达对抗教学训练系统

电子战的迅猛发展使得原有基于手控干扰的雷达对抗训练方式难以完全满足实战教学训练的需求。对此,提出并实现了一种新的、基于认知电子战的雷达对抗训练系统实验方案。该系统由雷达/雷达模拟子系统、干扰子系统和干扰评估子系统3部分构成,其中,干扰子系统在不同干扰模式间切换,干扰评估子系统通过机器学习和人工智能的方法可针对干扰模式进行迭代处理并形成最优干扰策略表,雷达/雷达模拟子系统则形成相应的电磁对抗环境仿真。室内仿真测试和室外真实应用环境测试结果均表明,该系统可有效提高雷达对抗训练的有效性和真实性,大大激发了学生对雷达对抗训练的学习兴趣。

ECM试验干扰环境设计的研究

以4种典型ECM战术为基础,研究ECM试验电子干扰环境的设计和生成,在每种战术环境设计分析中,主要论述干扰态势和功率控制两个方面。研究目的是满足复杂试验的需要,建立典型的ECM试验环境,有效提高电子对抗试验战场环境仿真能力。