Acta Geodaetica et Cartographica Sinica ›› 2023, Vol. 52 ›› Issue (4): 536-549.doi: 10.11947/j.AGCS.2023.20220097

• Geodesy and Navigation • Previous Articles     Next Articles

The method of sound speed errors correction in GNSS-acoustic location service

CHEN Guanxu1,2, GAO Kefu3,4, ZHAO Jianhu5, LIU Jingnan3,4,5, LIU Yanxiong1,2,5,6, LIU Yang1,2, LI Menghao1,2,6   

  1. 1. First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China;
    2. Key Laboratory of Oceanic Surveying and Mapping, Ministry of Natural Resources, Qingdao 266061, China;
    3. GNSS Research Center, Wuhan University, Wuhan 430079, China;
    4. National Engineering Center for Satellite Positioning System, Wuhan 430079, China;
    5. School of Geodesy and Geomatics, Wuhan University, Wuhan 430079, China;
    6. School of Earth Sciences and Engineering, Hohai University, Nanjing 211100, China
  • Received:2022-02-18 Revised:2023-02-11 Published:2023-05-05
  • Supported by:
    The National Key Research and Development Program of China (No. 2020YFB0505805);Basic Scientific Fund for National Public Research Institutes of China (No. 2022S03);The National Natural Science Foundation of China (No. 42004030);Financially supported by Laoshan Laboratory (No. LSKJ202205102);Consulting Research Project of Hubei Research Institute of China Engineering Science and Technology Development Strategy (No. HB2020B13);Technology Innovation Pilot Program of Shandong Province (No. 2020YFB0505800)

Abstract: Sound speed error is the main error source in GNSS-acoustic positioning, which restricts the accuracy of GNSS-acoustic positioning service. Based on the idea of marine space-time frame network, this paper studies the correction method of sound speed error in GNSS-acoustic location service. First, an improved empirical orthogonal function (EOF) method is proposed to construct the sound speed model hierarchically to eliminate the temporal-spatial representation error of sound speed. Then, for the sea area without sound speed profile, the idea of GNSS-acoustic location argument service is proposed based on GNSS tropospheric error processing method. Finally, for the underwater vehicle location argument service, the analysis of the ocean sound speed tomography method is carried out. The above correction idea of sound speed error is verified by using the measured data of 3000 m depth sea area in the South China Sea. The results show that the sound speed field constructed by the improved EOF method can determine the position of seafloor reference station with the decimeter-level accuracy. Based on the seafloor reference stations, the GNSS-acoustic location argument service proposed in this paper can provide decimeter-level accuracy location service for the ship within 3 km. The regional accuracy of the tomographic ocean sound speed profile in the depth interval below the underwater vehicle is better than 3.5 m/s.

Key words: GNSS-acoustic positioning, sound speed error, empirical orthogonal function, mapping function correction, sound velocity tomography

CLC Number: