Source level and directivity pattern of an underwater pulsed sound generator based on electrical discharge

Measurements of source level and directivity pattern of an underwater paraboloidal sound source based on electrical discharge are presented. The energy density of the pressure pulse is determined for both spherical wave and wave reflected by the paraboloid, together with their source levels. The directivity pattern of the paraboloidal source is obtained calculating the total energy of its acoustic signature. A spectral analysis performed in octave bands from 1 kHz to 500 kHz shows that the directivity increases with frequency as for a circular piston of equal aperture.