The adaptive filtering algorithm of GNSS/acoustic joint positioning

The layout of seafloor control points is an important part of constructing the marine space-time frame. And the reliable marine datum positioning models and methods are the premise and basis for the layout of high-precision seafloor control points. The widely used vessel sailing surveying has both flexibility and controllability. However, there are also the inevitable abnormal disturbance effects of the vessel, which leads to the distortion of the joint positioning model of seafloor control points. To solve this problem, a GNSS/acoustic joint positioning algorithm based on adaptive weight filtering is proposed. First, the GNSS/acoustic joint positioning mathematical model for combined sea surface and underwater observation processes is derived. Then the criterion of judging the dynamic disturbance when using the adaptive filter to solve the joint positioning model is studied, and the method of constructing adaptive factors for each state parameter is given. Finally, the simulated and the measured data were used to carry out the experiment. Results show that the adaptive filtering algorithm can effectively improve the abnormal influence of state disturbance on GNSS/acoustic joint positioning, and promote its positioning stability and accuracy. When the corresponding adaptive factors of various state parameters are constructed reasonably, the best performance of the filtering effect is proved.