机载激光探测空中目标脉冲回波特性研究

Research on Pulse Echo Characteristic of Airborne Laser Detecting Air Target

分析了空中目标态势的影响因素以及与激光脉冲回波参数的关系;考虑了目标的距离、速度、进入角和尺寸等因素对脉冲时延和展宽的影响,建立了相应的关系模型,得出了不同因素对脉冲时延和展宽有不同影响程度的主要结论;探讨了激光大气斜程传输过程,提出了一种激光大气斜程透射率计算方法,对一般的激光大气传输能量衰减模型进行了改进,得出激光脉冲能量随距离的增大和目标投影面积的减小而呈现指数衰减规律;搭建了实验系统平台,并对实验采集的回波数据进行了分析;对比了脉冲展宽理论计算结果与实测结果,二者相对误差控制在6%以内,具有很好的符合程度,验证了所建模型的有效性。得出的结论具有为反演空中目标态势信息提供一定参考的价值。

By analyzing the effect of some factors to air target, the relation between the factors and laser pulse echo parameter has been studied.Considering the effect of distance, speed, entering angel and target size to the time delay and broadening of pulse, the relation model is built,and the main conclusion of the different effects of different factors to pulse time delay and broadening is obtained. Based on the discussion of the process of laser atmospheric tansmittance in the slant path, a calculating method of laser atmospheric slant transmittance is proposed, and the general model of energy attenuation of laser tansmittance is improved and the exponential decay of laser energy changing with the increase of distance and decreace of projection area is concluded.Based on the experiment system built,the measured echo datas are analyzed. Through calculating and comparing the theoretical result and measured result, the relative error is in 6% and it is a better coincidence,which has verified the effectiveness of built model. The conclusion has significant referenced value on the inverse of air target situation.