Measurement of Ship Noise in Shallow Water

Abstract

While analyzing ship-radiated noise data that were taken in shallow water off Korea, we observed interference structure of acoustic frequency and for ranges. Acoustic propagation in shallow water is strongly affected by interaction with the boundariesof the ocean surface and sea floor.1),2) This multipath propagation leads to interference structure in the received signal, both spatially and temporally.3),4)The nature of this interference structure is strongly dependent on the geoacoustic parameters of the sea floor5). In this paper, the interference cycles arecalculated on the two different sediment types such as rock(station1) and sand(station2) bottom. Analysis method in this paper uses the pressure level as afunction of range and frequency at a various receiver depth.