A probabilistic underwater hyperbolic location system in low depth environment

Classical GPS/Acoustic positioning techniques using ranging position location in low depth environment suffer from the bad system geometry. The aim of this article is to propose a new hyperbolic position location technique that takes into account the system geometry. In our approach we process the position with the normal distribution of the beacon location defined as a sum of uniform distributions. A uniform distribution is derived from the surface of possible beacon localizations obtained with approximations of the hyperbolic approach in the case of noisy observations and for two boat positions. These surfaces increase when the geometry of the system is degraded and the probability in these cases decreases. These lower probabilities allow to minimize the influence of the bad geometry configuration in the finale estimation process. The proposed method is assessed on synthetic data and compared to the classical ranging approach.