【作者】 吕彪；

【导师】 张家树；

【作者基本信息】 西南交通大学 ， 通信与信息系统， 2006， 硕士

【摘要】 雷达是现代战争的利器,其能否在复杂电磁环境下正常工作,已成为决定战争胜负的重要因素。为了破坏敌方雷达的正常工作,保护己方的战略设施,必须采取各种措施对敌方雷达进行干扰。因此,研究对雷达的干扰具有重要的现实意义。 随着科学技术的日益发展,新的雷达体制层出不穷,给雷达干扰带来诸多困难,雷达干扰迫切需要新的概念、新的理论、新的技术。混沌学是近年来非线性科学领域的热门学科,海杂波的混沌特性使人们开始探索混沌在雷达中的应用,研究结果表明,混沌在雷达电子对抗领域具有广阔的应用前景。 本文研究了基于混沌的雷达干扰技术,针对两种典型的脉冲压缩体制雷达:线性调频雷达和二相编码雷达进行研究,研究内容包括以下几个方面: 1.分析了线性调频雷达和二相编码雷达的基本原理及信号特征,建立了接收机模型,详细介绍了线性调频雷达和二相编码雷达的脉冲压缩实现过程,并进行了计算机仿真。 2.研究了基于混沌的线性调频雷达欺骗干扰技术。线性调频雷达具有很强的抗噪声干扰能力,但可利用线性调频雷达频移-时延间存在强耦合的缺点,对其进行移频干扰。本文利用混沌的初值敏感性、伪随机性研究了线性调频雷达混沌移频干扰,包括混沌速度波门拖引干扰、混沌频率闪烁干扰、混沌假多普勒频率干扰;同时,本文还利用混沌的特性和雷达距离欺骗干扰的原理,研究了线性调频雷达混沌脉冲位置调制干扰,包括混沌脉冲位置调制距离波门拖引干扰、混沌脉冲位置调制距离假目标干扰。分别阐述了各种干扰方式的原理,并通过计算机仿真实验验证了干扰效果。 3.研究了基于混沌的二相编码雷达干扰技术。同线性调频雷达一样,二相编码雷达同样具有很强的抗噪声干扰的能力。本文利用混沌的初值敏感性、伪随机性,研究了二相编码雷达混沌脉冲相位调制干扰和混沌脉冲位置调制干扰,叙述了干扰原理,进行了计算机仿真,分析了干扰效果。 研究结果表明,利用混沌对线性调频雷达和二相编码雷达进行干扰是可行的,且具有良好的干扰效果。更多还原

【Abstract】 Radar is a key weapon in modern warfare. The performance stability of radar, especially under complex electromagnetic circumstances, will directly determine the results of warfare. In order to blind the enemy’s radar and to protect the strategic facilities of our own, various approaches are required to interfere with the enemy’s radar. Therefore, research on radar jamming is of importance in practice.With the increasing development of science and technology, more and more new radar systems emerge. This brings lots of troubles to radar jamming, so radar jamming needs new idea, new theory and new technology urgently. Fortunately, as a new branch of nonlinear science, chaos theory has attracted considerable attention in the world. Particularly, new explorations applying chaos theory in the radar systems are being developed, which originates from the finding of chaotic property of sea clutter. The achieved results show that there has a widely application prospect for chaos in the field of radar electronic countermeasure.This thesis focuses on radar jamming technology based on chaos. Two typical pulse compression radar systems, linear frequency modulation radar (LFM) and binary phase-coded radar (BC), are taken into account. The detailed contents of this thesis are listed in the following:At first of all, the basic principles and signal characteristics of LFM and BC have been analyzed, and the models of radar receiver have been established. The process of realizing pulse compression in LFM and BC has been introduced in detail. Then corresponding simulations have been carried out in computer.Secondly, the cheating jamming of LFM based on chaos has been investigated. It is difficult to jam LFM by noise. However, the signal of LFM has a strong coupling between frequency and time, which makes LFM can be jammed by shift-frequency jamming easily. On the basis of sensitivity to initial value and pseudo-random characteristics of chaos, chaotic shift-frequency jamming on LFM is studied, including chaotic velocity gate pull off jamming, chaotic Doppler-frequency-blinking jamming and chaotic false Doppler-frequency jamming. On the basis of characteristics of chaos and the principles of radar range cheating jamming, the method of chaotic pulse position modulation jamming on LFM is studied, includingchaotic pulse position modulation range gate pull off jamming and chaotic pulse position modulation range false target jamming. Each kind of principle of jamming method is expatiated respectively. Computer simulation experiments have been carried out to verify the jamming effect.Thirdly, the jamming technology of BC based on chaos has also been studied. Similar to LFM, BC has a strong power to resist noise jamming. On the basis of sensitivity to initial value and pseudo-random characteristics of chaos, chaotic pulse phase modulation jamming and chaotic pulse position modulation range cheating jamming are investigated. The principles of jamming, computer simulations and the associated jamming effect have been shown orderly.In conclusion, the research results indicate that it is feasible to use chaos to jam LFM and BC, moreover, the jamming effect is fairly well.更多还原