High-Rate GPS Seismology Using Real-Time Precise Point Positioning With Ambiguity Resolution

• Published in: IEEE transactions on geoscience and remote sensing Vol. 52; no. 10; pp. 6165 - 6180
• Main Authors: Xingxing Li, Maorong Ge, Cuixian Lu, Yong Zhang, Rongjiang Wang, Wickert, Jens, Schuh, Harald
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-10-2014; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Accuracy; Ambiguity; Clocks; Coseismic displacement; Delays; Displacement; Earthquakes; fault slip inversion; Global Positioning System; GPS seismology; high-rate GPS; Orbits; precise point positioning (PPP) ambiguity resolution; Real time; real-time PPP; Real-time systems; Receivers; Satellite navigation systems; Satellites; Seismic phenomena; Waveforms; Coseismic displacement; GPS seismology; precise point positioning (PPP) ambiguity resolution; high-rate GPS; real-time PPP; fault slip inversion
• ISSN: 0196-2892; 1558-0644
• DOI: 10.1109/TGRS.2013.2295373

With the availability of real-time high-rate GPS observations and precise satellite orbit and clock products, the interest in the real-time precise point positioning (PPP) technique has greatly increased to construct displacement waveforms and to invert for source parameters of earthquakes in real time. Furthermore, PPP ambiguity resolution approaches, developed in the recent years, overcome the accuracy limitation of the standard PPP float solution and achieve comparable accuracy with relative positioning. In this paper, we introduce the real-time PPP service system and the key techniques for real-time PPP ambiguity resolution. We assess the performance of the ambiguity-fixed PPP in real-time scenarios and confirm that positioning accuracy in terms of root mean square of 1.0-1.5 cm can be achieved in horizontal components. For the 2011 Tohoku-Oki (Japan) and the 2010 El Mayor-Cucapah (Mexico) earthquakes, the displacement waveforms estimated from ambiguity-fixed PPP and those provided by the accelerometer instrumentation are consistent in the dynamic component within few centimeters. The PPP fixed solution not only can improve the accuracy of coseismic displacements but also provides a reliable recovery of earthquake magnitude and of the fault slip distribution in real time.