【作者】 刘忠；

【导师】 王国玉；

【作者基本信息】 国防科学技术大学 ， 信息与通信工程， 2006， 博士

【摘要】 新体制雷达一般都综合运用了多种抗干扰技术,特别是采用了脉内或脉间相干的信号波形,使与雷达发射波形不匹配的干扰信号不能得到相应的处理增益,显著降低了压制或者欺骗干扰的效果,对雷达干扰技术的研究提出了严峻的挑战。本文针对线性调频脉冲压缩雷达的干扰问题,在跟踪该领域的研究前沿和发展态势的基础上,深入研究了基于数字射频存储(DRFM)技术的多种干扰样式。论文首先系统地论述了DRFM的工作原理、基本结构以及国内外的应用现状和发展趋势;从理论上对其采样量化过程引起的寄生信号电平进行了分析,对寄生信号抑制的技术手段和方法进行了讨论;对本振、采样时钟及其频漂、量化电平对其相参性的影响进行了分析;对基于DRFM的干扰系统的工作原理和实现方法进行了深入研究。接着对线性调频脉冲压缩雷达的转发式移频干扰技术进行了深入讨论,通过理论分析找到了移频干扰中心频率发生偏移的特征,该特征为雷达抗移频干扰提供了潜在的可能,同时也可为干扰方如何更有效地使用移频干扰提供了理论指导。为了隐藏移频干扰特征,又提出了产生多个假目标、覆盖假目标的改进型移频干扰方法。提出了基于DRFM技术的间歇采样直接转发干扰样式,从理论上对该干扰样式的原理及其独有的欺骗兼压制的干扰效果进行了分析,给出了干扰机理的物理解释,重点研究了该技术中的关键参数对干扰效果的影响,研究表明:该干扰样式与传统的欺骗干扰不同,它并非直接对距离、速度或角度等信息进行调制实现对雷达的欺骗,而是巧妙地利用线性调频脉冲压缩雷达的脉内相干性对雷达进行攻击,使雷达同时受到多个逼真假目标干扰,因此,该干扰样式的提出为新体制雷达的干扰提供了新的思路。在间歇采样直接转发干扰技术的基础上,进一步提出了间歇采样循环转发干扰样式,包括重复转发和逐次循环转发两种算法形式,并分别分析了两种算法的干扰效果,分析结果表明:两种方式各有特点,它们在有效假目标分布范围、干扰工作比等方面有明显区别,但它们都可使线性调频脉冲压缩雷达产生更多数目的幅度较强的逼真假目标,通过调节干扰参数,可对真目标前后的假目标数目、幅度和相对位置进行调整,实现对假目标参数的间接调控,从而可以对雷达的搜索、跟踪都产生丰富多样的干扰效果。最后,介绍了基于DRFM的间歇采样转发干扰机样机系统的设计与实现,给出了关键模块和样机系统的部分测试结果,并对它们进行了分析。本文的研究成果,是对线性调频脉冲压缩雷达干扰样式的丰富和发展,能够直接为我军雷达干扰装备研制提供理论指导,因此具有重要的理论意义和实际应用价值。更多还原

【Abstract】 Advanced radar systems generally employ various techniques of electronic counter-countermeasures (ECCM). Particularly by utilizing coherent characteristics of intra-pulse or interpulses, they can achieve coherent processing gain,and obviously decrease the efficiency of electronic jamming which signal waveforms are mismatched to a victim radar’s transmitted waveform. These radars present significant challenges to the research on techniques of electronic countermeasures (ECM). The advent of Digital Radio Frequency Memory (DRFM) and the growing application of DRFM to electronic warfare are providing a powerful means for effective jamming to the advanced radar system, which is used to sample, store and play back intercepted radar signals with high fidelity.On the basis of both domestic and foreign advanced ECM technique and its developing trend, this thesis has studied intensively some novel jamming techniques on linear frequency modulated (LFM) pulse compression (PC) radar.Firstly, the operational principle, basic structure, the developmental history and current and future trend in other countries of DRFM are introduced systematically, together with some successful applications appearing in the literature. Undesired spurs produced by the digitizing process undergone within DRFM are theoretically analyzed, and spurs reduction techniques and methods are discussed. Main influential factors such as local oscillator and sampling clock and quantification levels for the coherency of the replica signals in DRFM are analyzed too. The operational principle and implementation of an integrated deceptive jammer based on DRFM are studied in detail.Then, the ECM and ECCM of frequency-shifting to LFM PC radar are discussed in detail, and a signature of frequency-shifting jamming is theoretically analyzed. The signature can be utilized by radar for anti frequency-shifting jamming, on the other hand, it can be utilized to direct or control the use of frequency-shifting jamming more effectively. In order to conceal the signature by all means, some reformative technologies of frequency-shifting jamming are studied too, which can make radar obtain a train of false targets or cover-pulse false targets.A novel technique of interrupted-sampling and repeater jamming based on DRFM is proposed and studied in detail, its principle and jamming effect to LFM PC radar is analyzed in theory, and its physical explanation and some significative conclusions are given out; the effect and influence of key parameters is discussed emphatically. The conclusions show: the technique of interrupted-sampling and repeater jamming is different from the former deception ECM, which gives out error information such as range deception or velocity deception or angle deception by manipulative modulation to victim radar. The technique of interrupted-sampling and repeater jamming utilizes coherent characteristics of intra-pulse to attack LFM PC radar, and makes radar obtain a train of lifelike false targets without any identified features. In a word, the technique of interrupted-sampling and repeater jamming is better than the former deception ECM.On the basis of studying on interrupted-sampling and repeater jamming, a new jamming technology of interrupted-sampling and circular-repeater jamming is presented, including two algorithms such as repetitive repeater and one by one circular repeater. The jamming effect of both algorithms is analyzed, and the effect and influence of key parameters is discussed emphatically. Both jamming algorithms can make LFM PC radar obtain numerous lifelike false targets, and the number and amplitude and position of these false targets can be adjusted or controlled by way of changing some parameters of jammer.Finally, the design and implementation of interrupted-sampling and repeater jammer based on DRFM is introduced.The results of this thesis are beneficial not only to design coherent jammer, but also to develop the technology of jamming theory for attacking LFM PC radar.更多还原