Source levels for shallow underwater sound charges

This paper presents a simple method for removing the surface-reflected comp onent from the explosion waveform of signal underwater sound (SUS) charges detonated at shallow depths, in order to obtain accurate estimates of the s ource levels. The method is based on the repeated subtraction of time-shift ed segments of portions of the source waveform that are uncontaminated by t he surface reflection. The technique provides a method for an accurate esti mation of the source levels for charges detonated at depths shallower than 90 m. The method is evaluated by comparing the source levels from the proce ssed waveforms with results obtained by scaling source levels for deeper ch arges to depths of 58 and 18.3 m. (C) 1999 Acoustical Society of America. [ S0001-4966(99)02301-2].