不同BDS星历反演大气可降水量精度分析

基于陕西地区3个GNSS观测站2018年1～6月数据，利用北斗卫星导航系统进行水汽反演。首先利用不同星历产品计算水汽结果，分别与利用IGF解算的水汽结果、探空数据探测结果进行比较；再将不同星历得到的水汽结果进行相互对比。结果表明，利用3种星历都能获得精度和可靠性较高的水汽结果，其中精密星历和快速星历反演水汽的精度相当，各测站偏差均优于1 mm，标准差和均方根误差均优于3.5 mm；利用超快速星历（预报部分）反演水汽在各测站的偏差约为1 mm，标准差和均方根误差均优于5 mm。综合3种产品反演水汽的对应精度可知，利用3种星历产品均可反演大气可降水量，且超快速星历（预报部分）计算的水汽值可为气象预报提供参考依据。

Precision Analysis of Precipitable Water Vapor in Different BDS Ephemeris

Based on data of three GNSS observation stations in Shaanxi from January to June in 2018, the water vapor inversion is carried out by using Beidou satellite navigation system. We use different ephemeris products to calculate the water vapor, and compare them with the results calculated by IGF and radiosonde data. At the same time, we compare the water vapor results obtained by different ephemeris with each other. The results show that the three ephemeris can obtain high-precision and high-reliability water vapor results. The accuracy of water vapor inversion with precision ephemeris and fast ephemeris are equivalent, the deviation of each station is better than 1 mm, the standard deviation and root mean square error are better than 3.5 mm. The ultra-fast ephemeris (forecast part) is used to invert water vapor at each station with a deviation of about 1 mm, the standard deviation and root mean square error are better than 5 mm. Combining the corresponding accuracy of water vapor inversion of three products, it can be obtained that the three ephemeris products can invert precipitable water vapor and the water vapor value calculated by the ultra-fast ephemeris (forecast part) can provide a reference for weather forecast.