中断连续波去斜体制距离走动分析及补偿方法

Range Walk Analysis and Compensation Algorithm of Interrupted Continuous Wave Dechirp System

针对中断连续波去斜体制的高速目标距离走动及对信噪比的影响进行了定量分析,分析结果表明:发生距离走动时的差频信号是一个线性调频信号。针对该现象,提出了一种时域反转压缩补偿方法,利用信号时频特征,在时域生成时序反转的信号,与原信号共轭相乘去除调频斜率,实现信号压缩;同时提出了一种二次匹配滤波压缩的方法,基于速度搜索信息,计算距离走动时的差频信号调频斜率,生成相反斜率的匹配滤波器,进行二次匹配滤波消除距离走动。能够消除高速目标的距离走动影响,提高探测威力和探测精度,可以应用于去斜体制中断连续波探测雷达,在高速目标探测领域有很好的借鉴意义。

The paper makes a quantitative analysis on the range walk of high-speed target and its influence on signal-to-noise ratio in interrupted continuous wave dechirp system.The analysis results show that the difference frequency signal when range walk occurs is a LFM(linear frequency modula⁃tion)signal.Aiming at this phenomenon,a time-domain inversion compression compensation method is proposed,which uses the time-frequency characteristics of the signal to generate a time-reversed signal in the time domain,which is conjugated and multiplied with the original signal to remove the frequency modulation slope and realize signal compression.At the same time,a quadratic matched fil⁃ter compression method is proposed.Based on the speed search information,the frequency modula⁃tion slope of the difference frequency signal during range walking is calculated,and the matched filter with the opposite slope is generated.The range walking is eliminated by quadratic matched filtering.It can eliminate the influence of distance walking of high-speed targets,improve the detection power and detection accuracy,and can be applied to the declination system interrupt CW detection radar,which has a good reference significance in the field of high-speed target detection.