非线性方程法确定低空探测机载激光雷达消光系数边界值  

Constructing and solving the nonlinear equation of airborne lidar for determining the boundary value of the extinction coefficient for atmospheric aerosol in lower atmosphere

作　　者：熊兴隆[1] 蒋立辉[1] 冯帅[2] 庄子波[3] 马愈昭[1] 

机构地区：[1]中国民航大学天津市智能信号与图像处理重点实验室,天津300300 [2]中国民航大学工程技术训练中心,天津300300 [3]中国民航大学国际飞行学院,天津300300

出　　处：《光电子．激光》2012年第7期1356-1362,共7页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(41075013);中央高校基本科研基金(ZXH2011D003);中国民航大学校内基金(09QD14X)资助项目

摘　　要：提出了机载激光雷达进行低空探测时确定消光系数边界值的非线性方程法。首先根据机载激光雷达方程推导出消光系数边界值与机载激光雷达回波信号之间的函数关系,构建一个以消光系数边界值为变量的非线性方程。然后采用改进Jarratt法求此非线性方程的数值解,得到消光系数边界值。使用地基激光雷达真实回波信号数据模拟得到的机载激光雷达回波信号,进行了实验验证,并与斜坡法进行了比较。结果表明,本方法确定边界值的相对误差比斜坡法减小5.9%,由于其具有六阶的收敛特性,迭代次数仅为3次。该方法不需辅助测量设备,精度较高,收敛速度快,迭代次数少,具有良好的应用前景。A novel method based on the nonlinear equation of airborne lidar is proposed for determining the boundary value of the extinction coefficient for atmosphere aerosol in lower atmosphere. In the method the mathematical relation between the boundary value of the extinction coefficient and the lidar return signals is firstly deduced from the lidar equation. The relation is expressed by a nonlinear equation with the boundary value of the extinction coefficient as a variable to be determined. Then, the equation is solved numerically using the improved Jarratt iteration. The boundary value of the extinction coefficient for atmospheric aerosol is hence obtained. The method is used for the return signals of the airborne lidar. Which are obtained using the real return signals of the ground-based lidar. The obtained results are com- pared with those obtained using the ramp method. The results show that the relative error of boundary value of the extinction coefficient obtained using our method is smaller by 5.9 % than that using the ramp method. In our method only three times of iterations are required due to the six-order convergence property. No auxiliary equipment is needed. The method may explore a large number of applications be- cause of its high precision and fast convergence.

关 键 词：大气光学 机载激光雷达 改进Jarratt迭代法 消光系数 边界值 

分 类 号：TN958.98[电子电信—信号与信息处理]