二维粗糙面激光波束散射场量均方及相关函数的二阶统计特征

在高斯波束入射下二维随机粗糙面散射特征基础上，研究波束散射场量均方和相关函数的二阶统计特征，利用误差函数获取数值计算的解析表达式．数值计算了目标几种特殊材料表面，激光波束入射下，不同材料单、双站散射场量二阶统计特征随散射角度的变化情况．详细讨论了特殊材料表面介电常数、粗糙度、相干长度，入射／散射角分别对散射场相关函数的影响．散射场量均方值函数作为粗糙面散射的相干分量，针对不同材料单、双站探测条件下，定量分析其在相关函数中的比重及随散射角的分布特征．散射场量的均方和相关函数是统计数学本质数字特征，本文所做的工作将为研究激光波束入射下粗糙面散射场量其他高阶矩统计特征奠定基础，并通过定量分析统计均方在相关函数比值关系，为开展目标激光探测中与“散斑”有关的光学特征研究提供有效技术支持．

The second order statistical Characteristic of mean square and correlation function for Laser beam scattering fields from Two-dimensional rough surface

Based on the fields characteristics Gaussian beam scattering from the random rough surface, the fields second order statistical characteristic of mean square and correlation function for Gaussian beam is studied. Error function is used for numerical calculation analytical expression on these second order characteristics. As the laser beam incidence on several special material surfaces, the numerical methods analyze their second statistical characteristic changing with scattered angles in different backward and bi-station detected conditions. We detailly discuss that some factors include the permittivity of the material surface, roughness, coherence length, the incident / scattering angles which have influences on the correlation functions of scattering fields. The mean square of fields as rough surface scattering coherent component, it is quantitatively analyzed the ratio between mean square and correlation functions changing with scattering angles in different material and different backward and bi-station detected conditions. The mean square and correlation functions are the fundamental statistical characteristics, so our works will be based on researching other high order statistical moments of laser beam scattering from rough surface, and the quantitatively analyzing the ratio between mean square and correlation functions will further study to obtain key technologies for the some important light characteristics of laser speckle in laser detected applications.