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  - Chen, Kejie
T1  - Tightly integrated processing of high-rate GPS and accelerometer observations by real-time estimation of transient baseline shifts
JF  - The journal of navigation
N2  - The complementary advantages of high-rate Global Positioning System (GPS) and accelerometer observations for measuring seismic ground motion have been recognised in previous research. Here we propose an approach of tight integration of GPS and accelerometer measurements. The baseline shifts of the accelerometer are introduced as unknown parameters and estimated by a random walk process in the Precise Point Positioning (PPP) solution. To demonstrate the performance of the new strategy, we carried out several experiments using collocated GPS and accelerometer. The experimental results show that the baseline shifts of the accelerometer are automatically corrected, and high precision coseismic information of strong ground motion can be obtained in real-time. Additionally, the convergence and precision of the PPP is improved by the combined solution.
KW  - High-rate GPS
KW  - Accelerometer records
KW  - Baseline shift
KW  - Tight integration
KW  - Precise Point Positioning
Y1  - 2014
U6  - https://doi.org/10.1017/S0373463314000150
SN  - 0373-4633
SN  - 1469-7785
VL  - 67
IS  - 5
SP  - 869
EP  - 880
PB  - Cambridge Univ. Press
CY  - New York
ER  -