1.064μm激光大气散射离轴探测特性研究

Study on Off-axis Detection Characteristics of 1.064μm Laser Atmospheric Scattering

针对离轴激光驾束制导所受气溶胶的影响,基于Mie散射理论,分析了大气分子和气溶胶粒子的散射特性,建立了离轴激光探测模型,通过对1.064μm激光在低空大气传输特性的研究,仿真并分析了三种气溶胶类型与相位函数、直接辐射、散射辐射的相关关系。结果表明,气溶胶类型是影响离轴激光探测结果的一个重要因素;在气溶胶的影响下,直接辐射能量最高衰减60%;在气溶胶类型、相对湿度和探测器不变的情况下,短距离(1 km、3 km)探测辐照度强度下降较快,长距离(8 km)可在更远的离轴距离被探测器接收,且最终强度都趋近于1 W/m~2;在离轴探测角度不同时,较小的散射角会传播到更远的离轴距离,较大散射角会接收到更多的辐照度能量。

In view of the influence of aerosol on off-axis laser beam guidance,based on Mie scattering theory,the scattering characteristics of atmospheric molecules and aerosol particles are analyzed,and an off-axis laser detection model is established.By studying the transmission characteristics of 1.064μm laser in low-altitude atmosphere,the correlation between three aerosol types and phase function,direct radiation and scattered radiation is simulated and analyzed.Results show that aerosol type is an important factor affecting the off-axis laser detection results.Under the influence of aerosol,the maximum attenuation of direct radiation energy is 60%.Under the condition of constant aerosol type,relative humidity and detector,the irradiance intensity in short distance(1 km,3 km)decreases rapidly,while in long distance(8 km),it can be received by the detector at a further off-axis distance,and the final intensity approaches 1 W/m~2.When the off-axis detection angle is different,the smaller scattering angle will propagate to farther off-axis distance,and the larger scattering angle will receive more irradiance energy.