红外大气折射率剖面分布模式

Refractivity profile distribution model for infrared waves

针对光电测量设备的大气折射误差实时修正以及红外激光传输研究等问题,利用2006年至2010年间在新疆戈壁地区获取的大气参数探空实验数据,计算得到了两个特定的波长,即1.32μm和4μm对应的大气折射率平均剖面分布,进而提出了一种实用的折射率剖面分布模式——三参数指数分布模式。利用非线性最小二乘法,分别拟合得到了波长为1.32μm和4μm时的红外波在各季节内折射率的三参数指数剖面分布模式。采用统计得到的折射率剖面分布模式实时修正了光电设备的仰角测量数据,通过和实测模型的事后修正结果比较发现,二者的差值小于5″,实现了对当地光学测量数据大气折射误差的实时、快速修正。

Atmospheric refractivity significantly influences optoelectronic measuring accuracy and laser propagation,so an accurate knowledge of the refractivity profile is important.In this paper,calculations of the refractive index using atmospheric parameters for the near and middle infrared are carried out,and then the refractivity profiles of the Gobi zone in Xinjiang are obtained from the sounding data for the latest few years.The statistical distributions of the refractive index in every season for wavelengths of 4 μm and 1.32 μm are discussed in detail,and the three-parameter exponential mode is proposed to describe the mean refractivity profile.A three-parameter exponential profile for wavelengths of 4 μm and 1.32 μm in every season is given by nonlinear fitting.The statistical refractive profile is used to correct the refractive error of the data obtained from the optoelectronic equipments in real-time.This correction result is compared with the post correction result using the measured profile,with the difference of them less than 5″.