@article{TuWangLiu2016,
  author    = {Tu, Rui and Wang, L. and Liu, Z.},
  title     = {Real time monitoring ground motion using GPS with real time corrections},
  series = {Survey Review},
  volume    = {48},
  journal   = {Survey Review},
  publisher = {Wiley},
  address   = {Abingdon},
  issn      = {0039-6265},
  doi       = {10.1179/1752270614Y.0000000141},
  pages     = {79 -- 85},
  year      = {2016},
  abstract  = {The high rate GPS velocity determination technology which is based on the broadcast ephemeris and epoch differenced model can retrieve displacement of ground motion with the precision of a few centimetres to decimetres in real time. Moreover, the precision of the recovered displacement can be improved if the un-modelled errors such as broadcast ephemeris residuals, atmospheric residuals, multipath effects and high frequency noise are tackled more accurately. In this paper, we propose a method to improve the precision of the recovered displacement by appropriately making use of reference station corrections. For the reference stations, the coordinates are highly constrained to extract the error corrections that are to be broadcast via a communication link to the rover. After correcting the rover's observations, some errors such as ephemeris residuals and atmospheric residuals are effectively eliminated or at least reduced. This improves the accuracy of the observations and thus enhances the reliability of the velocity estimation. The displacement can be recovered by integrating the estimated velocity after de-trending using a linear trend that is caused by the un-corrected residuals. The series of validation results in the experiment have shown that the displacement of the simulated motion can be real time recovered with a precision of 1-2 cm, and is thus applicable for real time monitoring of the ground motion.},
  language  = {en}
}
@article{TuWang2014,
  author    = {Tu, Rui and Wang, Li},
  title     = {Real-time coseismic wave retrieving by integrated Kalman filter with observations of GPS, Glonass and strong-motion sensor},
  series = {Advances in space research},
  volume    = {53},
  journal   = {Advances in space research},
  number    = {1},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0273-1177},
  doi       = {10.1016/j.asr.2013.10.011},
  pages     = {130 -- 137},
  year      = {2014},
  abstract  = {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.},
  language  = {en}
}
@article{TuGeZhangetal.2013,
  author    = {Tu, Rui and Ge, Maorong and Zhang, Hongping and Huang, Guanwen},
  title     = {The realization and convergence analysis of combined PPP based on raw observation},
  series = {Advances in space research},
  volume    = {52},
  journal   = {Advances in space research},
  number    = {1},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0273-1177},
  doi       = {10.1016/j.asr.2013.03.005},
  pages     = {211 -- 221},
  year      = {2013},
  abstract  = {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.},
  language  = {en}
}
@article{TuChen2014,
  author    = {Tu, Rui and Chen, Kejie},
  title     = {Tightly integrated processing of high-rate GPS and accelerometer observations by real-time estimation of transient baseline shifts},
  series = {The journal of navigation},
  volume    = {67},
  journal   = {The journal of navigation},
  number    = {5},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {0373-4633},
  doi       = {10.1017/S0373463314000150},
  pages     = {869 -- 880},
  year      = {2014},
  abstract  = {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.},
  language  = {en}
}