Matched-field localization with single vector hydrophone in shallow water

Abstract

In this paper, matched-field localization with a single vector hydrophone is researched. In condition of ideal waveguide, the sound pressure field and vertical velocity were analyzed theoretically. The relationship between acoustic pressure field and vector field achieved that a vector hydrophone can be equivalent to vertical two element array with a certain vertical aperture. The depth of vector hydrophone is related to performance of matched field processing. The principle of minimum correlation coefficient of sound pressure and vertical vibration velocity should be observed. A wideband coherent matching processor is proposed, which has high resolution and good environmental tolerance compared to conventional matching processor by simulation of isothermal and negative gradient waveguide. Principal trials were done in the coastal waters of China. Depth of sea areas is 40m, and sound profile of the sea area is isothermal layers. We used low frequency sound source emitting a LFM signal as the sound source with frequency from 100Hz to 300Hz. The estimated range is 3.8km, which is consistent with the actual distance 4.05km. Sea trial validate that this technique is adaptive to passive localization, and hopeful to vector acoustic field modeling and three-dimensional localization of single vector.