ABSTRACT
Acoustic positioning systems, like the long baseline positioning system based on a sea-surface or seabed acoustic array, are often used for submarine vehicle navigation. The active-sonar positioning mode is however ill-posed and suffer from the sound speed error effect. We first propose an augmented acoustic navigation service based on a sea-surface and seafloor network by monitoring the acoustic delay errors in the acoustic observations, which is parameterized by a B-spline model. Then, we recommend a vehicle trajectory estimation model by accumulating a piece of acoustic observations with the acoustic delay error corrections within a specific time window. In the time window, the B-spline model is used for fitting the trajectory to conquer the ill-posed problem. The estimated B-spline trajectory can then be utilized to determine the state of the vehicle at any given time, including its location and velocity. It shows that the proposed augmented acoustic positioning model can achieve a navigation accuracy better than two meters.
