Calibration of hydrophones in a field with continuous radiation in a reverberating pool

COOMET.AUV.W-S1 supplementary comparison of free-field hydrophone calibrations in the frequency range 250 Hz to 8 kHz

“…Let us explain the mechanism of uncertainty occurrence. The transfer impedance Z ′ PH (f) of a projector-receiver pair in the sound field of water tank with reflecting boundaries can be written as the product of a pair of transfer impedance in a free field Z PH (f) and the so-called water tank transfer function H PH (f) [10,11]:…”

Signal-modelling methods applied to the free-field calibration of hydrophones and projectors in laboratory test tanks

“…Other methods reported in the literature have utilised noise or pseudo-random noise signals to undertake measurements in a diffuse-field in a reverberant tank [7,13,[16][17][18], with recently reported methods successfully conducting calibrations by measurement of the sound power in the reverberant field [19], or by using a complex weighted moving average (CWMA) method for deriving the transducer response from the reverberant field in a test tank. In the latter, the effect of reflections is eliminated by complex averaging of the frequency dependence of the electrical transfer impedance of the transducers, deriving the value of the free-field transfer impedance averaged over the effective frequency band of the measuring tank [20][21][22][23][24][25][26][27][28].…”

Finite-Element Method for Calculating the Sound Field in a Tank with Impedance Boundaries

“…In applications, it is usually more practical to consider a rectangular enclosed space with general impedance boundary conditions than one with ideal boundaries, but the former approach is yet to be studied fully in the field of acoustics. A nonanechoic tank is an important acoustic measuring device that is used widely for calibrating transducers [1,2] and measuring sound power [3,4] and the sound absorption coefficient of underwater acoustic materials [5,6]. Being able to predict the sound field in a nonanechoic tank reasonably and effectively will help understand the sound field characteristics and provide the necessary basis for acoustic measurements using nonanechoic tanks.…”