Positioning of periodic acoustic emitters using an omnidirectional hydrophone on an AUV platform

Abstract

The origin position of an emitted signal is commonly determined using arrays of synchronized receivers or through the use of directional receivers. In this paper a single omni-directional hydrophone used to estimate the position of periodic acoustic emitters in three dimensions is proposed and studied. The theory behind the method and the alterations to the common range differencing problem to adjust for a single receiver is explained. An extended Kalman filter and a Particle filter are suggested to provide iterative estimators for the state estimation problem. The primary focus of this paper is on the performance and robustness of these filters using measurements available from a single observer. The system containing a moving receiver and periodic emitter was modeled and simulated to validate the theory and analyze the performance when put through different noisy scenarios.

Experiments in the field with commercially available hardware have been conducted. The first trial used a boat as platform for the moving receiver, and data was collected and post-processed. The second trial used an AUV as platform where data was processed on-board in real time. Results from these trials show the algorithms combined with the hardware setups produce satisfactory position estimates for the purpose of finer scale behavioral tracking.