Deep water sound sources for ocean acoustic tomography and long-range navigation

The first test of the tunable organ-pipe was successfully conducted on 11 Sept. 2001. The sound source was efficient, powerful, and had unlimited operational depth, as well as a minimum level of high frequency harmonic content. The projector uses a narrow-band, highly efficient sound resonator, which is tuned to match the frequency and phase of a reference frequency-modulated signal. Since 2001, many deep-water ocean acoustic experiments have used this type of sound source. The source was successfully used for ocean acoustic tomography and long range navigation. Recently, it was shown that a bottom-deployed swept frequency array can be used for high-resolution seismic imaging of deep geological formations. The long-term operating experience of the sound sources demands the development of an improved sound source system. A finite-element analysis that shows the structural acoustics of the tunable resonator has been conducted to improve the acoustics of the sound source. The analysis gave a better solution ...