雷达有源干扰抑制算法研究

【作者】 廖胜男；

【导师】 唐斌；

【作者基本信息】 电子科技大学 ， 信息获取与探测技术， 2010， 硕士

【摘要】 雷达是现代战争中重要的利用电磁波探测目标的电子装备。随着雷达电子对抗技术的发展,电子反对抗技术作为影响雷达生存的重要因素引起国内外雷达工作者的广泛关注。本论文以线性调频脉冲压缩体制的对空情报雷达为对象,围绕有源干扰抑制技术展开研究。重点在有源加性复合干扰与新型干扰的干扰抑制算法研究,以及对常规有源干扰现有抑制算法的验证。本文的主要工作如下:第一、研究了典型有源干扰的产生机理与作用机理。包括常规有源干扰、有源加性复合干扰与灵巧噪声干扰。有源加性复合干扰与灵巧噪声干扰是本文的主要研究对象,通过仿真分析了其信号特征,并从理论上推导了其时域表达式与干扰性能。第二、针对有源加性复合干扰,研究了基于相位扰动原理的干扰抑制方法。在结合LFM信号特征的基础上,采用对雷达发射信号的前后脉冲分别附加近似正交的扰动相位,再通过相应于前一脉冲重复周期的匹配滤波器将复合干扰中的欺骗干扰成分加强,然后对脉冲压缩结果加以“惩罚”,最后采用匹配滤波逆运算恢复出目标回波信号。第三、考虑到加性复合干扰的产生机理与信号特征,研究了雷达有源加性复合干扰分步抑制算法。由于该算法抑制复合干扰直观,且可以运用已有的常规干扰抑制算法,故算法有一定的实用价值。该算法存在的不足之处是需要已知复合干扰信号的类型,在实际使用时需要在雷达系统中将该算法配合干扰类型识别以及抗干扰措施选取使用。第四、研究了一种基于LFM信号解线调的灵巧噪声干扰抑制算法。该算法以雷达前一脉冲重复周期的接收信号为参考,求得其与当前脉冲重复周期雷达接收信号的差拍信号,将目标信号移至低频,通过滤波抑制干扰,再通过差拍逆运算可以恢复出目标回波信号。第五、构建与实际情况相似的仿真平台,对现有常规有源干扰抑制算法进行验证。仿真平台的构建是通过适当修改某雷达站某次对抗现场试验中所采用的某型雷达、某型压制式干扰机与某型欺骗式干扰机的实际参数得到的。仿真验证的干扰抑制算法包括:基于对消的噪声调频干扰抑制算法与基于LFM雷达Stretch处理的距离假目标干扰抑制算法。更多还原

【Abstract】 Radar systems are important electronic equipments for the modern warfare, which detect targets by using electromagnetic waves. With the development of radar electronic countermeasures (ECM), the radar electronic counter countermeasures (ECCM) causes widespread attention at home and abroad as an important factor that affecting the survival of radar.The typical pulse compression (PC) radar system, which sends the linear frequency modulation (LFM), is taken as our research object. Aiming at promoting the anti-jamming capability of radar, we study the active interference suppression technology. In this thesis, the author focus on the suppression technology of active additive compound jamming and smart noise jamming, and validate the conventional active jamming suppression algorithmic. This thesis has principally conducted study in the following aspects:First, the mechanism of generation and action of the active jamming, which include conventional active jamming, active additive compound jamming and smart noise jamming are studied. Active additive compound jamming and smart jamming had been taken as the most important research object. In this chapter, The characteristics of the signals are analyzed, and their time domain expression and interference performance is studied also.Second, for the active additive compound jamming, an algorithm which is based on the phase-perturbed theory is studied. Take the characteristics of LFM signal into account, the jamming can be restrained by change the radar transmit signal to Slope-Varying LFM (SV LFM), and use jamming pulse compression to strengthen the jamming signal, then give the results of pulse compression a "punish" , and finally the echo signal can be restored by the previous pulse match filter.Third, taking the generation mechanism of additive compound jamming into account, the step to step suppression algorithm is studied. This algorithm is practical, because the conventional active jamming restrain method can be used. The disadvantage of this algorithm is that the class of the components of the jamming must be known at first, to resolve this, some jamming recognition methods and selection of radar electronic counter countermeasures is need to be added in the radar system.Fourth, an algorithm, based on LFM stretch processing, is studied to suppression the smart noise jamming. With a special reference signal, the target echo can be move to the low frequency, and the false target signal will be take a wide band frequency in frequency domain. Thus, a wave-trap technique can be utilized to cancel the jamming signal and then the target echo can be rebuild.Fifth, construct a simulation platform that similar to the actual situation, and use the simulation platform to validate the existing conventional active interference suppression algorithm. Taking confidentiality and the gap between simulation parameters and reality into account, simulation platform is constructed by adjust the actual parameters of and a certain type of radar and blanket jammer and deception jammer. Simulation of the jamming suppression algorithms include: noise frequency modulation (FM) jamming suppression algorithm based on the elimination of jamming, and a radar false targets suppression algorithm based on Stretch LFM treatment.更多还原