GTDM: a new model for generating global tropospheric delay

doi:10.13474/j.cnki.11-2246.2021.0047

Abstract

Abstract: Tropospheric delay is the main error source in GNSS positioning. Various existing tropospheric delay models have the disadvantage of overfitting, the details of delay changes in a short time. In this paper, the variation characteristics of tropospheric delay are analyzed by using the meteorological data of ECMWF from 2011 to 2017. It is found that the global tropospheric delay deviation between adjacent years of the same grid is mostly within 5 cm. Accordingly, a new tropospheric delay model GTDM is proposed. It has been verified that GTDM has a good fitting effect. In this paper, the data from 2016-2017 are used as the external compliance inspection data including the tropospheric delay product data of IGS stations provided by the IGS analysis center and the tropospheric delay calculated by the reanalysis of meteorological data by the sounding data. The results show that the accuracy of GTDM is higher than that of GZTD, GPT2w, UNB3m in global. A simple modeling method, GTDM can avoid overfitting the value of tropospheric delay and reflect the characteristics of tropospheric delay changes effectively.

Key words: tropospheric delay, tropospheric delay model, GZTD, GPT2w, UNB3m

CLC Number:

P228

MA Yongchao, Lü Zhiping, XU Guochang, CHEN Peng, YUAN Kansheng. GTDM: a new model for generating global tropospheric delay[J]. Bulletin of Surveying and Mapping, 2021, 0(2): 72-76.

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