General Introduction
(More information: https://navrs.wh.sdu.edu.cn/)
The Satellite Navigation and Remote Sensing group is founded by Prof. Guochang Xu in 2015, and now headed by Prof. Tianhe Xu. The group aims to exploit the principle of satellite navigation and remote sensing, as well as the corresponding applications. and has already started lectures and studies about some aspects of these research areas. The group is now focusing on the following three aspects:
National integrated PNT and seamless navigation in solar-terrestrial space. Focusing on the major needs of the country, the research content includes: the construction of the national comprehensive PNT system; deep-sea PNT-submarine reference and underwater navigation; deep-space PNT-deep-space reference and deep-space navigation; solar-terrestrial space seamless navigation-terminal and algorithm ; Flexible PNT and micro PNT software and hardware and core algorithms.
Marine environment monitoring and global sea level changes. Committed to solving major scientific issues, the main research content includes: spaceborne GNSS-R load index design; rapid on-board inversion of marine environmental parameters; research on the impact, meaning and mechanism of global/regional/offshore sea level changes.
Commercial multispectral small satellite payload design and innovative applications. Serving major practical applications, the main research contents include: commercial remote sensing small satellite constellation design; spaceborne spectrometer spectrum combination and filter design; real-time processing technology on spectral remote sensing satellites; innovative applications of commercial multispectral small satellites.
The group has a vast experimental laboratory equipped with various GNSS receivers, GNSS-R, UAV, remote control and communication devices, INS, laser scanner, optical cameras, computational hardware and real-time precise positioning software as well as space mission design software and other utilities as needed by researchers. The group provides an excellent platform of international exchange and opportunities studies abroad, and supports the applications of all science projects and talent projects.
Principal Investigator
Prof. Tianhe Xu (https://navrs.wh.sdu.edu.cn/yjdw/grjj/xutianhe.htm )
Team Members (1 full professor, 3 adjunct distinguished professors, 2 associate researcher, 1 lecturer, 4 Post-doctors. 11 Ph.D. and 15 master students)
Full Professor:Dr. Tianhe Xu. Mainly involved in the research of satellite navigation and marine gravity measurements.
3 adjunct distinguished professors: Dr. Guochang Xu, Dr. Hermann Josef Kaufmann and Dr. Luisa Bastos
Associate Researcher: Dr. Yan Xu, Dr. Wenfeng Nie
Postdoctoral Scientists:Nazi Wang, Dapeng Mu, .Nan Jiang, Min Li.
Graduate students:Chaonan Ji, Taihao Wang, Wenfeng Nie, Tong Liu, Zihang Feng, Shanyu Zhou, Mowen Li, Huanhuan Jin, Zhangzhen Sun, Chunhua Jiang, Jiangbo Song, Donghui Shen, Zhenlong Fang.
Main Research Grants:
1. National PNT system flexible architecture design and key technology demonstration verification, National Key R&D Project, Yuan, 15,000,000, (PI. Prof. Tianhe Xu)
2. High-performance cloud processing satellite navigation precision positioning and service technology, Sub-Project of National Key R&D Project, Yuan, 1,000,000,(PI. Dr. Yujun Du and Dr. Yan Xu)
3. Theory and method of establishing marine geodetic datum, Sub-Project of National Key R&D Project, Yuan, 1,200,000, (PI. Prof. Tianhe Xu)
4. Theories and methods for detecting global gravity field changes by fusing data from multiple types of low-orbit satellites, NSFC, key sub-project, Yuan, 780,000, (PI Prof. Tianhe Xu)
5. Research on Earth Rotation Parameter Prediction Method Combining Machine Learning and Nonlinear Adaptive Filtering, NSFC, general project, Yuan, 760,000, (PI Prof. Tianhe Xu)
6. Research on the Reference Frame Theory and Method of Refining Geocentric Coordinates Based on GNSS/SLR Data from Joint Ground Stations and LEO Satellites, NSFC, general project, Yuan, 840,000, (PI Prof. Tianhe Xu)
7. Theoretical Solution of Three-Body Problem and Research on Lunar Gravity Boost, NSFC, general project, Yuan, 832,000, (PI Prof. Guochang Xu)
8. Beidou Big Data Analysis System, Main Control Station of Beidou-3 Ground Transportation Control System, Beidou major special project sub-project, Yuan,1,000,000 (PI Prof. Tianhe Xu)
9. Long-term performance evaluation of Beidou-3's simplest navigation message, Beidou major special project sub-project, Yuan,670,000 (PI Prof. Tianhe Xu)
10. Product synthesis and evaluation software-complete clock error/tropospheric module, Beidou major special project sub-project, Yuan,500,000 (PI Prof. Tianhe Xu)
Selected Publications:
Books:
1. Xu, G. (2014): GPS – Theory, Algorithms and Applications, 1st Ed in Persian, Iran Technical University Press, ISBN 978-7-302-27164-2, 332 pages, translated from Xu (2007): GPS – Theory, Algorithms and Applications, 2nd Ed, Springer, translation organized by the Iran Technical University.
2. Xu, G., Xu, J. (2013): Orbits - 2nd order singularity-free solutions, 2nd Ed, Springer Heidelberg, 420 pages, in English
3. Xu, G. (2010) (Ed.): Sciences of Geodesy - I, Advances and Future Directions, Springer Heidelberg, chapter topics (authors): Aerogravimetry (R Forsberg), Superconducting Gravimetry (J Neumeyer), Absolute and Relative Gravimetry (L Timmen), Deformation and Tectonics (L Bastos et al.), Analytic Orbit Theory (G Xu), InSAR (Y Xia), Marine Geodesy (J Reinking), Kalman Filtering (Y Yang), Equivalence of GPS Algorithms (G Xu et al.), Earth Rotation (F Seitz and H Schuh), Satellite Laser Ranging (L Combrinck), in English, 507 pages
4. Xu, G. (2012) (Ed.): Sciences of Geodesy - II, Advances and Future Developments, Springer Heidelberg, chapter topics (authors): General Relativity and Space Geodesy (L Comblinck), Global Terrestrial Reference Systems and their Realizations (D Angermann et al), Ocean Tide Loading (M Bos and HG Scherneck), Photogrammetry (P Redweik), Regularization and Adjustment (Y Shen and G Xu), Regional Gravity Field Modelling (H Denker), VLBI (H Schuh and J Boehm), in English, 391 pages
Selected Articles in recent Three years:
**************2020***************************
1. Gao Fan, Xu Tianhe, Wang Nazi .A shipborne experiment using a dual-antenna reflectometry system for GPS/BDS code delay measurements.J Geod94,88 (2020). https://doi.org/10.1007/s00190-020-01421-4
2. Mu Dapeng, Xu Tianhe, Xu Guochang. An investigation of mass changes in the Bohai Sea observed by GRACE.J Geod 94,79 (2020). https://doi.org/10.1007/s00190-020-01408-1
3. Liu, Tong, Tianhe Xu, Wenfeng Nie, Mowen Li, Zhenlong Fang, Yujun Du, Yiping Jiang, and Guochang Xu. "Optimal Independent Baseline Searching for Global Gnss Networks." Journal of Surveying Engineering 147, no. 1 (2021): 05020010.
4. Guan, Meiqian, Tianhe Xu, Fan Gao, Wenfeng Nie, and Honglei Yang. "Optimal Walker Constellation Design of Leo-Based Global Navigation and Augmentation System." Remote Sensing 12, no. 11 (2020): 1845.
5. Jiang, Chunhua, Tianhe Xu, Shuaimin Wang, Wenfeng Nie, and Zhangzhen Sun. "Evaluation of Zenith Tropospheric Delay Derived from Era5 Data over China Using Gnss Observations." Remote Sensing 12, no. 4 (2020): 663.
6. Li, Mowen, Wenfeng Nie, Tianhe Xu, Adria Rovira-Garcia, Zhenlong Fang, and Guochang Xu. "Helmert Variance Component Estimation for Multi-Gnss Relative Positioning." Sensors 20, no. 3 (2020): 669.
7. Wang, Jian, Tianhe Xu, Wenfeng Nie, and Guochang Xu. "A New Algorithm for Multi-Baseline Solution Based on Equivalence Principle." Measurement Science and Technology (2020).
8. Wang, Jian, Tianhe Xu, Wenfeng Nie, and Guochang Xu. "Gps/Bds Rtk Positioning Based on Equivalence Principle Using Multiple Reference Stations." Remote Sensing 12, no. 19 (2020): 3178.
9. Wang, Junting, Tianhe Xu, Wenfeng Nie, and Xiaokang Yu. "The Construction of Sound Speed Field Based on Back Propagation Neural Network in the Global Ocean." Marine Geodesy, no. just-accepted (2020): 1-14.
10. Wang, Junting, Tianhe Xu, Bingsheng Zhang, and Wenfeng Nie. "Underwater Acoustic Positioning Based on the Robust Zero-Difference Kalman Filter." Journal of Marine Science and Technology (2020): 1-16.
11. Wang, Shuaimin, Tianhe Xu, Wenfeng Nie, Chunhua Jiang, Yuguo Yang, Zhenlong Fang, Mowen Li, and Zhen Zhang. "Evaluation of Precipitable Water Vapor from Five Reanalysis Products with Ground-Based Gnss Observations." Remote Sensing 12, no. 11 (2020): 1817.
12. Wang, Shuaimin, Tianhe Xu, Wenfeng Nie, Jian Wang, and Guochang Xu. "Establishment of Atmospheric Weighted Mean Temperature Model in the Polar Regions." Advances in Space Research 65, no. 1 (2020): 518-28.
**************2019***************************
1. Dapeng Mu#, Tianhe Xu*, Guochang Xu. Detecting coastal ocean mass variations with GRACE mascons. Geophysical Journal International, 2019, 217(3): 2071–2080, https://doi.org/10.1093/gji/ggz138. （SCI, IF=2.528）
2. Min Li#, Tianhe Xu*, Biao Lu, Kaifei He. Multi-GNSS Precise Orbit Positioning for airborne gravimetry over Antarctica, GPS Solutions, 2019, 23:53, DOI: 10.1007/s10291-019-0848-9. （SCI, IF=4.727）
3. Zhangzhen Sun#, Tianhe Xu*, Fan Gao, et al. The Quality Assessment of Non-integer-hour Data in GPS Broadcast Ephemerides and Its Impact on the Accuracy of Real-time Kinematic Positioning Over the South China Sea. CMES, 2019, 119 (2): 263-280. DOI: 10.32604/cmes.2019.04425. (SCI, IF=0.581)
4. Guobin Chang#*, Tianhe Xu, Chao Chen, Bing Ji, Shengquan Li. Switching position and range-domain carrier-smoothing-code filtering for GNSS positioning in harsh environments with intermittent satellite deficiencies. Journal of the Franklin Institute, 2019, 356: 4928-4947. DOI: 10.1016/j.jfranklin.2019.04.005.（SCI, IF=3.576）
5. Min Li#, Tianhe Xu*, Frank Flechtner, Christoph Förste, Biao Lu and Kaifei He. Improving the Performance of Multi-GNSS (Global Navigation Satellite System) Ambiguity Fixing for Airborne Kinematic Positioning over Antarctica. Remote Sensing. 2019, 11(8), 992; DOI: 10.3390/rs11080992. （SCI, IF=4.118）
6. Nan Jiang#, Tianhe Xu, Yan Xu*, Guochang Xu and Harald Schuh. Assessment of Different Stochastic Models for Inter-System Bias between GPS and BDS. Remote Sensing. 2019, 11(8), 989; DOI: 10.3390/rs11080989. （SCI, IF=4.118）
7. Honglei Yang#, Tianhe Xu*, Wenfeng Nie, Fan Gao, Meiqian Guan. SLR Validation and Evaluation on BDS Precise Orbits from 2013 to 2018. Advances in Space Research, 2019, 64: 475-490. DOI: 10.1016/j.asr.2019.04.030.（SCI, IF=1.97）
8. Guobin Chang#*, Tianhe Xu, Yifei Yao, Haitao Wang, Huaien Zeng. Ionospheric delay prediction based on online polynomial modeling for real-time cycle slip repair of undifferenced triple-frequency GNSS signals. Measurement, 2019, 146: 289-297. DOI: 10.1016/j.measurement.2019.06.036. （SCI, IF=2.359）
9. Shuaimin Wang#, Tianhe Xu*, Wenfeng Nie, Jian Wang, Guochang Xu. Establishment of atmospheric weighted mean temperature model in the polar regions, Advances in Space Research, 2019, doi:10.1016/j.asr.2019.10.001（SCI, IF=1.97）
10. Zhangzhen Sun#, Tianhe Xu*, Chunhua Jiang, Yuguo Yang, Nan Jiang. An improved prediction algorithm for Earth’s polar motion with considering the retrograde annual and semi-annual wobbles based on least squares and autoregressive model, Acta Geodaetica et Geophysica, 2019, doi: 10.1007/s40328-019-00274-4. （SCI, IF=0.942）
11. Xia Ren#*, Yuanxi Yang, Jun Zhu, Tianhe Xu. Comparing satellite orbit determination by batch processing and extended Kalman filtering using inter-satellite link measurements of the next-generation BeiDou satellites. GPS Solutions, 2019, 23:25, DOI: 10.1007/s10291-018-0816-9. （SCI, IF=4.727）
12. Min Li#*, Karl-Hans Neumayer, Frank Flechtner, Biao Liu, Christoph Förste, Kaifei He, Tianhe Xu. Performance Assessment of Multi-GNSS Precise Velocity and Acceleration Determination over Antarctica. Journal of Navigation, 2018, DOI: 10.1017/S0373463318000656. （SCI, IF=1.580）
13. Chen Chao#, Guobin Chang*, Nanshan Zheng, Tianhe Xu. GNSS multipath error modeling and mitigation by using sparsity-promoting regularization. IEEE Access, 2019, Vol.7, 24096-24108, DOI: 10.1109/ACCESS.2019.2899622. （SCI, IF=3.557）
14. Honglei Yang#, Tianhe Xu*, Wenfeng Nie, Fan Gao and Meiqian Guan. Precise Orbit Determination of BDS-2 and BDS-3 Using SLR. Remote Sensing. 2019, 11(23), 2735; DOI:10.3390/rs11232735.（SCI, IF=4.118）
15. Chunhua Jiang#, Tianhe Xu*, Yujun Du, Zhangzhen Sun and Guochang Xu. A parallel equivalence algorithm based on MPI for GNSS Data Processing. Journal of Spatial Science. 2019, DOI: 10.1080/14498596.2019.1696718. （SCI, IF=1.078）
16. Tianhe Xu#*, Kangkang Chen, Huijie Xu, Yuguo YANG. BDS Orbit Determination with Combined GNSS and SLR Observations. European Geosciences Union (EGU) General Assembly 2019, Vol. 21, EGU2019-2839, Vienna, Austria, 8–13 April 2019.
17. Honglin Tang#, Tianhe Xu*. Multi-GNSS Kinematic Relative Positioning of Multiple Base Stations and Its Application in Deformation Monitoring. China Satellite Navigation Conference (CSNC) 2019 Proceedings: Lecture Notes in Electrical Engineering 562，pp. 106-113, 2019. https://doi.org/10.1007/978-981-13-7751-8_11（EI）
18. Zhenlong Fang#, Wenfeng Nie, Tianhe Xu*, Zhizhao Liu, and Shiwei Yu. Accuracy Assessment and Improvement of GNSS Precise Point Positioning Under Ionospheric Scintillation. China Satellite Navigation Conference (CSNC) 2019 Proceedings: Lecture Notes in Electrical Engineering 563，pp.400-411, 2019. https://doi.org/10.1007/978-981-13-7759-4_36（EI）
**************2018***************************
1. Wenlin Yan#*, Luisa Bastos, Jose Goncalves, Americo magalhaes，Tianhe Xu. Image-aided platform orientation determination with a GNSS/low-cost IMU system using robust-adaptive Kalman filter. GPS Solutions, 2018, 22:12, DOI: 10.1007/s10291-017-0676-8. （SCI, IF=4.727）
2. Fan Gao#, Tianhe Xu*, Nazi Wang, Chunhua Jiang, Yujun Du, Wenfeng Nie and Guochang Xu. Spatiotemporal Evaluation of GNSS-R Based on Future Fully Operational Global Multi-GNSS and Eight-LEO Constellations, Remote Sensing, 2018, 10(1): 67; DOI:10.3390/rs10010067. (SCI, IF=3.406).
3. Guobin Chang#*, Tianhe Xu*, Qianxin Wang. M-estimator for the 3D symmetric Helmert coordinate transformation. Journal of Geodesy, 2018, 92(1): 47-58. DOI: 10.1007/s00190-017-1043-9(SCI, IF=4.633).
4. Qianxin Wang#, Guobin Chang*, Tianhe Xu. Representation of the rotation parameter estimation errors in the Helmert transformation model. Survey Review, 2018, 50(358): 69-81. DOI: 10.1080/00396265.2016.1234806 (SCI, IF=0.929)
5. Guobin Chang#, Tianhe Xu*, Yifei Yao, Qianxin Wang. Adaptive Kalman filter based on variance component estimation for the prediction of ionospheric delay in aiding the cycle slip repair of GNSS triple-frequency signals. Journal of Geodesy, 2018, 92(11): 1241-1253. DOI: 10.1007/s00190-018-1116-4 (SCI, IF=4.633).
6. Wenfeng Nie#, Tianhe Xu*, Adrià Rovira-Garcia, José Miguel Juan Zornoza, Jaume Sanz Subirana, Guillermo González-Casado, Wu Chen, Guochang Xu. The Impacts of the Ionospheric Observable and Mathematical Model on the Global Ionosphere Model, Remote Sensing, 2018, 10(2): 169; DOI:10.3390/rs10020169. (SCI, IF=3.406).
7. Nazi Wang #, Tianhe Xu*, Fan Gao, and Guochang Xu. Sea Level Estimation Based on GNSS Dual-Frequency Carrier Phase Linear Combinations and SNR, Remote Sensing, 2018, 10(3): 470; DOI:10.3390/rs10030470. (SCI, IF=3.406).
8. Min Li#, Kaifei He, Tianhe Xu*, Biao Lu. Robust adaptive filter for shipborne kinematic positioning and velocity determination during the Baltic Sea experiment, GPS Solutions, 2018, 22:81, DOI: 10.1007/s10291-018-0747-5. （SCI, IF=4.727）
9. Wenfeng Nie#, Tianhe Xu*, Adrià Rovira-Garcia*, José Miguel Juan Zornoza, Jaume Sanz Subirana, Guillermo González-Casado, Wu Chen, Guochang Xu. Revisit the calibration errors on experimental slant total electron content (TEC) determined with GPS, GPS Solutions, 2018, 22:85, DOI: 10.1007/s10291-018-0753-7. （SCI, IF=4.727）
10. Guobin Chang#*, Tianhe Xu, Haitao Wang. M-estimator based robust unscented Kalman filter through statistical linearization. Transactions of the Institute of Measurement and control, 2018, DOI: 10.1177/0142331218793925. （SCI, IF=1.579）
11. Min Li, Karl-Hans Neumayer, Frank Flechtner, Biao Liu, Christoph Förste, Kaifei He, Tianhe Xu. Performance Assessment of Multi-GNSS Precise Velocity and Acceleration Determination over Antarctica. Journal of Navigation, 2018, DOI: 10.1017/S0373463318000656. （SCI, IF=1.580）
12. Guobin Chang#*, Chao Chen, Yuanxi Yang ,Tianhe Xu. Tikhonov regularization based modeling and sidereal filtering mitigation of GNSS multipath errors. Remote Sensing, 2018,10, 1801, DOI:10.3390/rs10111801. (SCI, IF=3.406)
13. Zhangzhen Sun, Tianhe Xu*, Fan Gao, et al. The Quality Assessment of Non-integer-hour Data in GPS Broadcast Ephemerides and Its Impact on the Accuracy of Real-time Kinematic Positioning Over the South China Sea[J]. CMES, 2018. (SCI, IF=0.581)
14. Tianhe Xu#*, Kangkang Chen, Huijie Xu, Yuguo YANG. BDS Clock Combination of iGMAS Analysis Centers and Its Performance Evaluation. European Geosciences Union (EGU) General Assembly 2018, Vol. 20, EGU2018-2756, Vienna, Austria, 8–13 April 2018.
15. Kaifei He#*, Tianhe Xu, Christoph Foerste, Svetozar Petrovic, Franz Barthelmes, Zhenjie Wang, Yumiao Tian, and Frank Flechtner GNSS Integrated Doppler Velocity Determination for GEOHALO Airborne Gravimetry. European Geosciences Union (EGU) General Assembly 2018, Vol. 20, EGU2018-3671, Vienna, Austria, 8–13 April 2018.
16. Yujun Du#*, Tianhe Xu, Wenfeng Nie, Fan Gao, Guochang Xu. A second-order analytical solution for satellite motion: implementation, improvements and validation. 42nd COSPAR Scientific Assembly 2018, July 14-22, 2018 Pasadena, California, USA.
17. Ren Lei#, Xu Tianhe*. Research on Smoothing Filtering Algorithm of BDS/GPS Slow Deformation Monitoring Sequence. China Satellite Navigation Conference (CSNC) 2018 Proceedings: Lecture Notes in Electrical Engineering 497，pp. 33-44, 2018. https://doi.org/10.1007/978-981-13-0005-9_3（EI）
18. Xu Huijie#, Xu Tianhe*, Ai Qingsong, Wang Shengchao. The Long-Term Performance Analysis and Comparison of BDS on-Board Atomic Clock Based on Precise Clock Products of IGS Analysis Centers .China Satellite Navigation Conference (CSNC) 2018 Proceedings: Lecture Notes in Electrical Engineering 497, pp.593-605, 2018. https://doi.org/10.1007/978-981-13-0005-9_48 (EI).
19. Zhang Bingsheng#, Xu Tianhe*, Gao Ruru. Research on Acoustic Velocity Correction Algorithm in Underwater Acoustic Positioning. China Satellite Navigation Conference (CSNC) 2018 Proceedings: Lecture Notes in Electrical Engineering 499, pp. 859-873, 2018. https://doi.org/10.1007/978-981-13-0029-5_72 (EI).
20. 蒋春华#，徐天河，乔晶，杜玉军，王庆，许国昌*. 拉格朗日/高斯无奇点卫星运动方程推导与分析. 测绘学报，2018，47（4）：455-464. DOI: 10.11947/j.AGCS.2018.20170082. (EI).
21. 加松#，徐天河*，杨红雷. LS+AR极移预报模型的两种修正算法. 测绘学报，2018，48（S0）：71-77. DOI: 10.11947/j.AGCS.2018.20180296. (EI).
