TY  - JOUR
A1  - Tu, Rui
A1  - Zhang, Hongping
A1  - Ge, Maorong
A1  - Huang, Guanwen
T1  - A real-time ionospheric model based on GNSS Precise Point Positioning
JF  - Advances in space research
N2  - This paper proposes a method of real-time monitoring and modeling the ionospheric Total Electron Content (TEC) by Precise Point Positioning (PPP). Firstly, the ionospheric TEC and receiver's Differential Code Biases (DCB) are estimated with the undifferenced raw observation in real-time, then the ionospheric TEC model is established based on the Single Layer Model (SLM) assumption and the recovered ionospheric TEC. In this study, phase observations with high precision are directly used instead of phase smoothed code observations. In addition, the DCB estimation is separated from the establishment of the ionospheric model which will limit the impacts of the SLM assumption impacts. The ionospheric model is established at every epoch for real time application. The method is validated with three different GNSS networks on a local, regional, and global basis. The results show that the method is feasible and effective, the real-time ionosphere and DCB results are very consistent with the IGS final products, with a bias of 1-2 TECU and 0.4 ns respectively.
KW  - Ionospheric monitoring and modeling
KW  - Precise Point Positioning (PPP)
KW  - Real time
KW  - Total Electron Content (TEC)
KW  - Global Navigation Satellite System (GNSS)
KW  - Differential Code Biases (DCB)
Y1  - 2013
U6  - https://doi.org/10.1016/j.asr.2013.06.015
SN  - 0273-1177
SN  - 1879-1948
VL  - 52
IS  - 6
SP  - 1125
EP  - 1134
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Tu, Rui
A1  - Wang, Li
T1  - Real-time coseismic wave retrieving by integrated Kalman filter with observations of GPS, Glonass and strong-motion sensor
JF  - Advances in space research
N2  - A method of real-time coseismic wave retrieving was proposed based on the tight integration of GPS, Glonass and strong-motion sensor observations, the validation and precision analysis have been made by an experimental data. The series of results have been shown that: by the integrated Kalman filter and multi-sensors, the coseismic waves can be optimally recovered by complement the advantages of each other, especially when the observation conditions are very bad. In additional, the results are not significantly effected by different receiver clock error processes for the integration solution.
KW  - GPS and Glonass
KW  - Strong-motion sensor
KW  - Baseline shift
KW  - Integrated Kalman filter
KW  - Real-time earthquake monitoring and early warning
Y1  - 2014
U6  - https://doi.org/10.1016/j.asr.2013.10.011
SN  - 0273-1177
SN  - 1879-1948
VL  - 53
IS  - 1
SP  - 130
EP  - 137
PB  - Elsevier
CY  - Oxford
ER  -