脉冲雷达梳状回波现象机理分析

Analysis of Comb Jamming Signals of Pulse Radar

基于单脉冲雷达在火箭发射初始段时经常接收到梳状回波信号,通过雷达距离显示器图像数据,从信号出现时间、功率强度、脉冲间距和脉冲数量等四方面对多次任务中的梳状回波特性进行分析统计。结果表明,该梳状回波的脉冲间距变化规律在多次任务中表现相同,具有"间距相等且随时间递增"的鲜明特点。同时,排查了可能产生梳状回波的三种模式,结合梳状回波脉冲间距反映出的地面反射体距离和散射截面积仿真计算结果,指出发射工位形成的角反射器效应是引发箭载应答机被连锁触发产生梳状回波的主要原因。

In allusion to the phenomenon of comb jamming signals that monopulse radar received during the rocket powered flight, the comb signals＇ four characters including emergence time, amplitude, interval and number of signal are measured through the displayed images of the radar. Statistical analysis show that all the comb jamming signals have the same change regulation, moreo- ver, the signal intervals are equal and increasing along with the flight time. Based on the discussing of three probable models of the comb signal generating, the model that the transponder on the rocket is chain triggered by reflecting signals of a reflector somewhere on the ground is considered to conform to the four characters of the comb signal. According to the simulating of RCS and range of the signal interval needed by the reflector, the comer reflector effect of rocket launching workplace is regarded as the major cause that leads to the chain trigger.