Acta Geodaetica et Cartographica Sinica ›› 2023, Vol. 52 ›› Issue (11): 1844-1857.doi: 10.11947/j.AGCS.2023.20220609

• Geodesy and Navigation • Previous Articles     Next Articles

Underwater gravity FKF matching enhancement algorithm based on local SCHA modeling

HUANG Yan1,2, LI Shanshan2, LI Xinxing2, SONG Xingguang3, FAN Diao2, WAN Hongfa2   

  1. 1. National Innovation Institute of Defense Technology, Academy of Military Science, Beijing 100071, China;
    2. Information Engineering University, Zhengzhou 450001, China;
    3. Beijing Aerospace Control Center, Beijing 100094, China
  • Received:2022-10-25 Revised:2023-09-19 Published:2023-12-15
  • Supported by:
    The National Natural Science Foundation of China (Nos. 42174007;42174013)

Abstract: An underwater gravity matching navigation method based on federal Kalman filter (FKF) and spherical cap harmonic analysis (SCHA) modeling of local gravity field is proposed. Firstly, based on the well posed boundary value problem, the gravity gradient complex combination observation of FKF subsystem filter is constructed. Then, adjusted spherical harmonic analysis (ASHA) is used to optimize the spherical crown harmonic modeling method of local gravity field, so as to quickly establish a more accurate moving window spherical crown harmonic model between the local ocean gravity field centered on the matching point and the spatial position. Based on this model, the measurement equation of sub-filter is established. Finally, the prediction residual vector is used to design an adaptive information distribution factor to fuse the state estimation and covariance of each sub-filter to obtain the optimal estimator of inertial navigation position error. The experimental results show that the gravity FKF matching algorithm modeled by SCHA keeps the positioning error of 24-hour navigation within 1.1 n miles, and the navigation positioning accuracy is improved by more than 85%; The positioning accuracy of 10 day long navigation has been improved by 88.7%. The algorithm can overcome the defect of the inertial navigation system due to the accumulation of time error to some extent, improve the navigation and positioning accuracy of the system, and increase the robustness of the matching algorithm.

Key words: FKF, SCHA, gravity gradient, complex combination, match navigation, ASHA

CLC Number: