TY  - JOUR
A1  - Tu, Rui
A1  - Ge, Maorong
A1  - Wang, Rongjiang
A1  - Walter, Thomas R.
T1  - A new algorithm for tight integration of real-time GPS and strong-motion records, demonstrated on simulated, experimental, and real seismic data
JF  - Journal of seismology
N2  - The complementary advantages of GPS and seismic measurements are well recognized in seismotectonic monitoring studies. Therefore, integrated processing of the two data streams has been proposed recently in an attempt to obtain accurate and reliable information of surface displacements associated with earthquakes. A hitherto still critical issue in the integrated processing is real-time detection and precise estimation of the transient baseline error in the seismic records. Here, we report on a new approach by introducing the seismic acceleration corrected by baseline errors into the state equation system. The correction is performed and regularly updated in short epochs (with increments which may be as short as seconds), so that station position, velocity, and acceleration can be constrained very tightly and baseline error can be estimated as a random-walk process. With the adapted state equation system, our study highlights the use of a new approach developed for integrated processing of GPS and seismic data by means of sequential least-squares adjustment. The efficiency of our approach is demonstrated and validated using simulated, experimental, and real datasets. The latter were collected at collocated GPS and seismic stations around the 4 April 2010, E1 Mayor-Cucapah earthquake (Mw, 7.2). The results have shown that baseline errors of the strong-motion sensors are corrected precisely and high-precision seismic displacements are real-timely obtained by the new approach.
KW  - High-rateGPS
KW  - Strong-motion records
KW  - Baseline error
KW  - Tight integration
KW  - Precise point positioning
Y1  - 2014
U6  - https://doi.org/10.1007/s10950-013-9408-x
SN  - 1383-4649
SN  - 1573-157X
VL  - 18
IS  - 1
SP  - 151
EP  - 161
PB  - Springer
CY  - Dordrecht
ER  - 
TY  - JOUR
A1  - Tu, Rui
A1  - Ge, Maorong
A1  - Zhang, Hongping
A1  - Huang, Guanwen
T1  - The realization and convergence analysis of combined PPP based on raw observation
JF  - Advances in space research
N2  - In order to speed up Precise Point Positioning (PPP)'s convergence, a combined PPP method with GPS and GLONASS which is based on using raw observations is proposed, and the positioning results and convergence time have been compared with that of single system. The ionospheric delays and receiver's Differential Code Bias (DCB) corrections are estimated as unknown parameters in this method. The numerical results show that the combined PPP has not caused significant impacts on the final solutions, but it greatly improved Position Dilution of Precision (PDOP) and convergence speed and enhanced the reliability of the solution. Meanwhile, the convergence speed is greatly influenced by the receiver's DCB, positioning results in horizontal which are better than 10 cm can be realized within 10 min. In addition, the ionosphere and DCB products can be provided with high precision.
KW  - GPS and GLONASS
KW  - Precise Point Positioning
KW  - Raw observation
KW  - DCB
KW  - Combine
Y1  - 2013
U6  - https://doi.org/10.1016/j.asr.2013.03.005
SN  - 0273-1177
VL  - 52
IS  - 1
SP  - 211
EP  - 221
PB  - Elsevier
CY  - Oxford
ER  -