水汽对折光修正精度的影响分析

针对当前部分折光修正的工程应用常常忽略水汽影响的现状,选取了国内4个不同地域的气象站点,基于1995年的数百组历史气象探空数据,利用射线描迹法分别仿真计算包含水汽和忽略水汽2种情况下由于大气折射引起的测距误差和测角误差,并对这4个站点不同仰角和不同时间的测距偏差和测角偏差进行统计分析,结果表明：水汽是构成测量残差的一个重要误差源,对于精度要求较高的折光修正系统,水汽的影响不能忽略.该分析结果可为其他需要考虑大气折射效应影响的高精度光学测量工程领域提供参考.

Analysis of the Impact of Water Vapor on the Accuracy of Optical Wave Refraction Correction

The influence of water vapor is often ignored in engineering application during data processing of optical wave refraction correction. By using several hundreds of sets of radiosonde data in 1995, which were collected in four meteorological stations of different regions in China, ranging errors and elevation angle measurement errors tak- ing into consideration water vapor and neglecting water vapor were computed with ray tracing algorithm. Statistical analysis of the above ranging and angular measurement deviations with respect to elevation angle and day oPtime shows that water vapor is an important source of residual errors and it should not be ignored, especially in high pre- cision data processing of optical wave refraction correction systems. The results provide a valuable reference to other high-precision optical measurement engineering fields which have to consider the effect of atmospheric refraction.