【摘要】 结合GNSS水汽层析算法的假设条件以及水汽密度随高程变化的特点,通过设置水汽密度随高度变化的合理阈值,提出一种地基GNSS水汽层析的自动垂直非均匀分层方法。利用香港地区连续6 d的GNSS观测数据,分别采用自动垂直非均匀分层方法和传统垂直均匀分层方法开展区域GNSS水汽层析实验,并以ECMWF数据为参考进行精度验证。结果表明,采用自动垂直非均匀分层方法进行GNSS水汽层析得到的大气湿折射率的偏差均值和均方根误差(RMSE)的均值分别为3.9 mm/km和4.6 mm/km,相对于垂直均匀分层方法减小约20.4%和23.3%。更多还原

【Abstract】 Taking into account the assumptions of GNSS water vapor tomography algorithm and the characteristics of water vapor density changing with elevation, we propose an automatic vertical non-uniform stratification method for GNSS water vapor tomography by setting a reasonable threshold value of water vapor density changing with height. To carry out the regional GNSS water vapor tomography test, we use GNSS observation data in Hong Kong for 6 consecutive days, using the automatic vertical non-uniform stratification method and the traditional vertical uniform stratification method. Taking the ECMWF data as a reference, the accuracy of GNSS water vapor tomography is verified. The results show that the mean deviation and the mean root mean square error(RMSE) of the wet refractive index obtained by the automatic vertical non-uniform stratification method is 3.9 mm/km and 4.6 mm/km, which decreases by about 20.4% and 23.3%, respectively, compared with the vertical uniform stratification method.更多还原