Next Article in Journal
Machine Learning for LTE Energy Detection Performance Improvement
Previous Article in Journal
Improved Optical Waveguide Microcantilever for Integrated Nanomechanical Sensor
Previous Article in Special Issue
Height Variation Depending on the Source of Antenna Phase Centre Corrections: LEIAR25.R3 Case Study
Open AccessArticle

Improving the GRACE Kinematic Precise Orbit Determination Through Modified Clock Estimating

1
GNSS Research Center, Wuhan University, Wuhan 430079, China
2
School of Geodesy and Geomatics, Wuhan University, Wuhan 430079, China
3
Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, 181 Chatham Road South, Hung Hom, Kowloon 999077, Hong Kong
*
Author to whom correspondence should be addressed.
Sensors 2019, 19(19), 4347; https://doi.org/10.3390/s19194347
Received: 19 August 2019 / Revised: 30 September 2019 / Accepted: 6 October 2019 / Published: 8 October 2019
(This article belongs to the Special Issue GNSS Data Processing and Navigation)
Utilizing global positioning system (GPS) to determine the precise kinematic orbits for the twin satellites of the Gravity Recovery and Climate Experiment (GRACE) plays a very important role in the earth’s gravitational and other scientific fields. However, the orbit quality is highly depended on the geometry of observed GPS satellites. In this study, we propose a kinematic orbit determination method for improving the GRACE orbit quality especially when the geometry of observed GPS satellites is weak, where an appropriate random walk clock constraint between adjacent epochs is recommended according to the stability of on-board GPS receiver clocks. GRACE data over one month were adopted in the experimental validation. Results show that the proposed method could improve the root mean square (RMS) by 20–40% in radial component and 5–20% in along and cross components. For those epochs with position dilution of precision (PDOP) larger than 4, the orbits were improved by 50–70% in radial component and 17–50% in along and cross components. Meanwhile, the Allan deviation of clock estimates in the proposed method was much closer to the reported Allan deviation of GRACE on-board oscillator. All the results confirmed the improvement of the proposed method. View Full-Text
Keywords: clock estimating; GRACE; kinematic precise orbit determination; PPP-AR; GPS clock estimating; GRACE; kinematic precise orbit determination; PPP-AR; GPS
Show Figures

Figure 1

MDPI and ACS Style

Zhou, X.; Jiang, W.; Chen, H.; Li, Z.; Liu, X. Improving the GRACE Kinematic Precise Orbit Determination Through Modified Clock Estimating. Sensors 2019, 19, 4347.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop