Characterization of the acoustic signature of an Ocean Explorer class AUV

The radiated noise from Autonomous Underwater Vehicles (AUV's) can interfere with on-board sensors and with certain type of missions. It is thus important to understand the parameters controlling the AUV self noise. In this thesis, measurement techniques and analyses are developed to investigate the mechanisms contributing to the acoustic noise of an Ocean Explorer class AUV. Measurements of the AUV acoustic signature are performed in a reverberant tank, after the tank is qualified to establish a reliable procedure to measure the AUV source levels. The measurement results are compared that obtained in an anechoic tank and in open-water. Acoustic measurements are correlated with vibration measurements performed on various components of the AUV, in order to identify the dominant components. From the results, some preliminary mitigation procedures to reduce the AUV acoustic signature are developed.