Depth discrimination of an acoustic source based on modal energy distribution - performance analysis/

Abstract

A recently proposed method [Apelfeld, Y., Depth Discrimination of an Acoustic Source Based on Modal Energy Distribution. MIT, 2007] for rough, but fast and robust depth classification of acoustic sources was investigated in realistic towing scenarios. The method uses modal energy distribution as a categorical indicator for the source depth. In this study we analyzed the method performance in two major towing patterns: the "yo-yo" pattern and the "one-time" depth sampling pattern. The position of the array elements was obtained using the MOOS-IvP simulation package. Among the main towing parameters of the performance evaluation was the pitch angle of the array. The main finding of this study is the discovery of a relationship between vertical orientation of the array and the relative source bearing. Thus, downward array orientation leads to relatively high separation capability for sources located at 00 relative bearing. In the contrary, upward array orientation leads to high separation capability for sources located at the opposite horizontal relative bearing (1800). This relationship implies direct tactical considerations on the AUV deployment that are discussed and summarized in this study.