基于机载窄带雷达的舰船目标多普勒特性分析

摘要

For the problem of the identify capability of non-cooperative ship on the sea in the narrow band airborne radar system,the three-dimensional micro-motion equations included yaw,pitch and row of uniform linear moving ship are built firstly.Then the periodicity characteristic and effects to the distance between radar and ship’s scatter point are analyzed.The echo of single frequency continuous wave radar is obtained then, composition and characteristics of echo Doppler frequency are researched finally.Theoretical analyses results show that the three-dimensional micro-motion may lead to spectral expansion and different time-frequency curves of each scattering point.Furthermore,the time-frequency curves change linearly like the linear frequency modulated (LFM)signal in short time,but in long time,they change irregularly in the complex sinusoidal form.%针对机载窄带雷达探测海面非合作舰船目标识别能力不足问题，首先建立了舰船横滚、俯仰和偏航三维微动下舰船运动方程，在此基础上建立了窄带雷达探测舰船的回波信号模型，分析了回波信号多普勒频率成分及其特征。理论分析结果表明，舰船三维微动会导致雷达回波信号的多普勒频率相对无微动情况下出现频谱展宽；并且不同位置的散射点具有不同的时频变化曲线；在短时间内，各散射点微多普勒时频曲线以类似 LFM 形式的线性关系变化，在较长时间内以类似正弦信号形式周期性变化，其周期与横滚角变化周期相同。