利用探空产品评估GNSS-PPP估计ZTD精度

无线探空测站可以提供高精度和高垂直分辨率的大气产品。为评估GNSS精密单点定位获得的天顶对流层延迟(ZTD)的精度,将无线探空产品获得的ZTD作为真值,选取中国地区4个IGS观测站及其附近的探空测站2014—2018年的数据进行试算和分析。针对两种产品空间分辨率不一致性问题,利用GNSS气象观测值来弥补探空测站与GNSS测站高程的不匹配。实验结果表明:GNSS气象观测能够较好地弥补探空测站与GNSS测站高程的不一致性;GNSS精密单点定位技术获取的ZTD与探空产品估算的ZTD差值的RMS值小于4cm。

Evaluating the Accuracy of ZTD Obtained by GNSS-PPP Using Radiosonde Products

Radiosonde provides atmospheric products with high precision and high vertical resolution. In order to evaluate the accuracy of zenith troposphere delay(ZTD) obtained by GNSS precise point positioning, taking ZTD obtained by radiosonde products as true value, the data of four IGS observations in China and those of the nearby sounding stations from 2014 to 2018 are selected for calculation and analysis. Considering the inconsistency of spatial resolution between these two products, the GNSS meteorological observations are applied to compensate the mismatch of altitude between radiosonde stations and GNSS stations. The experiment results show that GNSS meteorological observations can well compensate the inconsistency of altitude between radiosonde stations and GNSS stations, and the RMS value of the difference between the ZTD obtained by GNSS precise point positioning technology and the ZTD estimated by sounding products is less than 4cm.