Determination of the hydrophone phase response during periodic calibrations

traditional amplitude calibration, which is why its results depend on the art of the experimenter. A calculation method for determining the phase response of a hydrophone is proposed, which makes it possible to reduce the labor intensity of its periodic calibrations. Based on the experimentally confirmed applicability of the minimum-phase system concept to a hydrophone, the calibrated hydrophone is represented by a model in the form of an advance link and a minimum-phase fourpole network. Based on the results of the primary calibration, the equivalent radius of the hydrophone determine. No phase measurements are performed during periodic calibrations. The amplitude response of sensitivity is determined, according to which, using the Hilbert transform, the minimum phase response of the hydrophone is calculated. The phase response of the hydrophone sensitivity is obtained as the sum of the minimum phase response and the frequency dependence of the phase incursion of the sound wave during its propagation in water over a distance equal to the equivalent radius of the hydrophone. An experiment to determine the equivalent radius of a hydrophone is described. Using the calculation method, the labor intensity of periodic verification is reduced many times over, the load is reduced, and the resource of a specialized measurement standard is saved, since the need to use high-rank standards during periodic calibrations disappears.

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