LOAPEX: The long-range ocean acoustic propagation experiment

Abstract

This paper describes the recent long-range ocean acoustic propagation experiment (LOAPEX) and presents initial results. LOAPEX was conducted between 10 September and 10 October 2004, and was closely coordinated with two other experiments, BASSEX and SPICEX. LOAPEX provided low-frequency broadband acoustic transmissions to vertical hydrophone arrays covering most of the deep ocean water column, and to horizontal hydrophone arrays surrounding the Eastern North Pacific Ocean. Two of the primary objectives are to explain the strong acoustic arrivals that are received in the deep ocean shadow zone, and to better understand the roles of scattering and diffraction in general. Transmission paths to the vertical hydrophone arrays varied from 50 to 3200 km. [Work supported by the Office of Naval Research, Code 321OA.]