Recorded noise as a source of measurement for propagation loss

Abstract

Repetitive bursts of recorded reef noise were broadcast from an underwater loudspeaker and used to measure propagation loss in shallow water. The method has advantages because sound levels in the bandwidth of interest can be measured directly and give a simple determination of attenuation due to bottom interaction. Surface scattering can be neglected because it does not contribute to energy loss when the signal of interest is recorded noise. A comparison of summer and winter results gives a direct measure of the extra propagation loss due to downward refraction.