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.

Research on the self-defence electronic jamming decision-making based on the discrete dynamic Bayesian network

The manner and conditions of running the decision-making system with self-defense electronic jamming are given. After proposing the scenario of applying discrete dynamic Bayesian network to the decision making with self-defense electronic jamming, a decision-making model with self-defense electronic jamming based on the discrete dynamic Bayesian network is established. Then jamming decision inferences by the aid of the algorithm of discrete dynamic Bayesian network are carried on. The simulating result shows that this method is able to synthesize different targets which are not predominant. In this way, various features at the same time, as well as the same feature appearing at different time complement mutually; in addition, the accuracy and reliability of electronic jamming decision making are enhanced significantly.

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.

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.

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.

Performance analysis of multi-group three-tuple cross-eye jamming

Monopulse radar is widely used in military.Jamming monopulse radar has always been a research hotspot in electronic warfare(EW).Cross-eye jamming has always been considered as the most effective measures to jam with monopulse radar.In this paper, we propose a multi-group three-tuple crosseye jamming structure where each group contains three antenna elements with a definite phase and an amplitude relationship.Then, based on the principle of monopulse angle measurement, the error angle is deduced theoretically.Simulations show that such a multi-group three-tuple cross-eye jamming structure performs better than the multi-element cross-eye jamming structure previously proposed, and the analysis of the centroid shows that the centroid of the structure proposed in this paper is more widely distributed in space.

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.

高对抗强博弈场景下雷达波形设计思路

未来陆域突击作战中高对抗强博弈场景使得雷达与目标间博弈日趋激烈,雷达波形作为雷达装备的核心和基础特征,将是提高雷达对目标检测性能的关键因素。该文首先梳理高对抗强博弈场景下的军事需求和发展现状,然后从波形产生与处理、目标和环境信息参数化建模、波形博弈方法等方面展开讨论,可为雷达在复杂电磁环境下如何提升装备作战效能提供设计参考。

对瞬时测频干扰机理的研究

瞬时测频(instantaneous frequency measurement,IFM)接收机是电子侦察中非常重要的测频资源,其结构简单、灵敏度高、侦察频带宽、分辨率高,可以快速测定被测信号的频率,在现代电子战中得到广泛应用。基于IFM微波鉴相器在某一瞬间只能响应一个信号的特性,结合IFM工作原理,研究了一种新的(超过2个信号)对IFM干扰策略,并分析了干扰机理,通过模拟仿真对IFM的干扰效果进行了评估。仿真结果表明:多信号交叠可以对IFM系统产生明显的干扰效果,可以使得其无法测得正确频率,并错误地输出同时到达信号指示。

基于威胁机制-双重深度Q网络的多功能雷达认知干扰决策

针对传统深度Q网络(deep Q network,DQN)在雷达认知干扰决策中容易产生经验遗忘,从而重复执行错误决策的问题,本文提出了一种基于威胁机制双重深度Q网络(threat warning mechanism-double DQN,TW-DDQN)的认知干扰决策方法,该机制包含威胁网络和经验回放2种机制。为了验证算法的有效性,在考虑多功能雷达(multifunctional radar,MFR)工作状态与干扰样式之间的关联性的前提下,搭建了基于认知电子战的仿真环境,分析了雷达与干扰机之间的对抗博弈过程,并且在使用TW-DDQN进行训练的过程中,讨论了威胁半径与威胁步长参数的不同对训练过程的影响。仿真实验结果表明,干扰机通过自主学习成功与雷达进行了长时间的博弈,有80%的概率成功突防,训练效果明显优于传统DQN和优先经验回放DDQN(prioritized experience replay-DDQN,PER-DDQN)。

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。

电子战无人机反向交叉眼干扰研究

针对机载两源反向交叉眼干扰在实际应用中遇到的参数容限严苛和干信比需求高的问题,提出了一种创新的解决方案,即利用电子战无人机(EWUAV)搭载反向交叉眼干扰机对敌方制导雷达进行抵近干扰。首先,建立了EWUAV反向交叉眼干扰模型,通过深入分析该模型,揭示出机载两源反向交叉眼干扰模型实则是其一个特例;其次,在确定干扰有效性方面,设定了一个明确的指标:当视在假目标的爆炸范围不触及被保护平台的物理边界时,即认为干扰达到预期效果。此外,文中还详细推导了雷达指示角,创新性地将其参数分为几何与电参数两类进行深入分析;最后,通过一系列仿真实验,充分证明了所提方法不仅有效,而且在参数容限和干信比需求方面表现更为宽松和优越。

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。

频控阵对施放随队支援电子干扰的影响研究

针对频控阵(FDA)雷达辐射波束“弯曲”特性对电子支援飞机遂行随队支援电子干扰任务过程产生的影响展开分析.首先,建立FDA雷达结构模型,在此基础上分析FDA雷达测向欺骗性能对敌方干扰机天线测向对准过程的影响,以及FDA雷达对干扰机施放随队支援干扰的抑制效果.分析结果表明,FDA雷达能够使无源测向系统产生测角误差,进而影响干扰发射天线对干扰接收天线的空域覆盖.同时,基于FDA的自适应波束形成器能够有效抑制电子战飞机施放的随队支援干扰,进而实现对突防编队的探测及跟踪.

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。

Robust adaptive radar beamforming based on iterative training sample selection using kurtosis of generalized inner product statistics

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial filtering.If the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation effect.To cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range dimension.The principle is presented,and the validity is proven by simulation results.

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。