Research on calibration of the sound source at very low frequency

Very low frequency sound waves are becoming more and more widespread in underwater sound application, but the calibration on the very low frequency sound wave equipment-the sound source level of very low frequency acoustic source is very difficult, especially in shallow water environment. The propagation loss method can be used on the calibration of very low frequency acoustic source: when very low frequency acoustic source produces continuous signal, the sound pressure apart from the sound source center 1 meter can be obtained using the propagation model according to the steady-state signal received by the hydrophone. Then calibrating the very low frequency acoustic source can be carried out. The validity of this method has been confirmed through experiments and error analysis..