一种LFM雷达回波对消干扰算法  

Echo cancelling algorithm for the LFM radar

作　　者：王玉军[1,2] 赵国庆[1] 王宏伟[1] 

机构地区：[1]西安电子科技大学电子对抗研究所,陕西西安710071 [2]空军工程大学电讯工程学院,陕西西安710077

出　　处：《西安电子科技大学学报》2008年第6期1031-1035,共5页Journal of Xidian University

基　　金：武器装备预研基金资助(9140A07020806DZ01)

摘　　要：根据线性调频(LFM)信号群延迟特性,提出了一种针对LFM雷达的回波对消干扰算法.首先将LFM信号与其自身延迟信号的共轭相乘,用所得频率差对LFM信号进行移频,然后根据目标雷达散射截面积特性进行幅度和相位调制,可产生与目标回波同频反相的信号,达到与目标回波对消的目的.给出了一种实现此算法的干扰机结构,并提出了减小非线性相位误差的方法.理论分析与仿真表明,该算法在未知调频斜率的情况下可有效降低进入雷达接收机的回波信号功率,且在干扰机有较大转发延迟的情况下依然有效.A new algorithm is proposed for radar echo cancelling based on the group delay of the LFM （Linear Frequency Modulated） signal. Firstly, the received signal is multiplied by the conjugation of its delayed version to get the frequency difference between them. The received signal＇s frequency is then shifted using the frequency difference. According to the target＇s RCS（Radar Cross Section）, phase and amplitude modulation are made in order to get the signal having the same frequency as the echo pulse but with the opposite phase. This signal cancels the radar echo signals. One of the jammer structures which can realize the algorithm is given and the method for reducing nonlinear phase errors is presented. Theoretical analysis and simulation show that the novel algorithm effectively reduces the signal power received by the radar receiver even when the chirp rate is unknown. The algorithm is also workable when the jammer has a large time delay.

关 键 词：雷达对抗 干扰 对消 线性调频 有源隐身 

分 类 号：TN972.31[电子电信—信号与信息处理]