SSIEGNOS: A New Asian Single Site Tropospheric Correction Model

Liangke Huang,Shaofeng Xie,Junyu Li,Jun Chen,Chuanli Kang,Lilong Liu

doi:10.3390/ijgi6010020

Abstract

This paper proposes a new Asian single site tropospheric correction model called the Single Site Improved European Geostationary Navigation Overlay Service model (SSIEGNOS) by refining the European Geostationary Navigation Overlay Service (EGNOS) model at a single site. The performance of the SSIEGNOS model is analyzed. The results show that (1) the bias and root mean square (RMS) error of zenith tropospheric delay (ZTD) calculated from the EGNOS model are 0.12 cm and 5.87 cm, respectively; whereas those of the SSIEGNOS model are 0 cm and 2.52 cm, respectively. (2) The bias and RMS error show seasonal variation in the EGNOS model; however, little seasonal variation is observed in the SSIEGNOS model. (3) The RMS error decreases with increasing altitude or latitude in the two models; however, no such relationships were found in the bias. In addition, the annual predicted bias and RMS error in Asia are −0.08 cm and 3.14 cm for the SSIEGNOS model, respectively; however, the EGNOS and UNB3m (University of New Brunswick) models show comparable predicted results. Relative to the EGNOS model, the annual predicted bias and RMS error decreased by 55% and 48%, respectively, for the SSIEGNOS model.

Highlights

Tropospheric delay is the dominant error source in Global Navigation Satellite System (GNSS) technologies, which can be as high as approximately 2 m in the zenith direction for the propagating radio signal
T0herefore, we suggest that the SSIEGNOS mod0e.0l2 can be employed as a real-time single site troposp-0.h02eric correction model for Very Long Baseline Interferometry (VLBI) technique or othe0r space geodetic techniques in Asia
Five years of zenith tropospheric delay (ZTD) data from 2008 to 2012 of 46 international GNSS service (IGS) sites distributed in Asia were used to investigate the performance of the SSIEGNOS model

Summary

Introduction

Tropospheric delay is the dominant error source in Global Navigation Satellite System (GNSS) technologies, which can be as high as approximately 2 m in the zenith direction for the propagating radio signal. Empirical tropospheric correction models, such as the Hopfield model and Saastamoinen model, can be used to calculate the tropospheric delay at arbitrary sites based on the provided meteorological data. Both models require real-time meteorological parameters for the calculations because using standard meteorological parameters results in poor accuracy. It is obvious that they cannot satisfy real-time tropospheric delay correction for space geodetic techniques

Objectives

Conclusion