粗糙球体和锥体目标激光散射非相干分量比

Incoherent component ratio of laser scattering from rough sphere and cone targets

为了研究激光散斑对目标探测的影响,采用物理光学近似方法,进行了平面波激光照射在粗糙球体和圆锥体目标时对散射场统计特性的理论分析,推导了粗糙体目标散射场量的二阶统计矩,数值计算了粗糙球体和锥体的非相干散射分量比随粗糙度、散射角、半径及目标材料的变化情况。结果表明,散射角的变化对粗糙球体散射非相干分量比有影响,粗糙度变大,目标的非相干分量占总散射分量的比重越大;随着粗糙球体半径变小,球体表面越粗糙;圆锥体目标散射非相干分量比的峰值位置随粗糙度变化而不同,但其峰值均位于镜反射方向上;金属类材料比非金属抛光铝材料的非相干分量比小,且半径变化与非相干分量比成正比。该研究结果可为更复杂目标激光散射特性和激光散斑探测、识别的研究提供一定的参考价值。

In order to study the effect of laser speckle on target detection,the theoretical analysis of the statistical characteristics of the scattering field when the plane wave laser irradiates the rough sphere and cone target was carried out by using the physical optics approximation method,and the second order statistical moment of the scattering field quantity of rough targets was derived.The variation of incoherent scattering component ratio of rough sphere and cone with roughness,scattering angle,radius,and target material is calculated numerically.The results show that the change of scattering angle has an effect on the incoherent component ratio of rough sphere scattering.The larger the roughness,the larger the proportion of incoherent component of target to the total scattering component.As the radius of the rough sphere becomes smaller,the surface of the sphere becomes rougher.The peak position of incoherent component ratio of cone target scattering varies with roughness,but its peaks are all located in the direction of specular reflection.The incoherent component ratio of metallic materials is smaller than that of non-metallic polished aluminum materials,and the radius change is proportional to the incoherent component ratio.The research results provide some reference value for the study of laser scattering characteristics of more complex targets and laser speckle detection and identification.