US 5,694,375 A · Ultra-broadband hydrophone

Abstract

The present invention relates to an ultra-broadband hydrophone which has major electronic components and one mechanical component. The first electronic component comprises a flux-gate magnetometer for sensing changes in an ambient magnetic field and for creating an electrical signal representative of the ambient magnetic field. The second electronic component comprises an electrical circuit for demodulating the electrical signal and a low pass filter for smoothing the demodulated signal. The mechanical component is a magnetic diaphragm for receiving acoustic pressure waves and for causing changes in the ambient magnetic field in response to the received acoustic pressure waves. In a preferred embodiment, the hydrophone of the present invention also includes a sub-Hertz differential magnetic field winding for generating a differential magnetic field which nulls the ambient magnetic field about the flux-gate magnetometer.

Claims9

Dependent claims

An acoustic ultra-broadband hydrophone device which comprises:

first sensing means for sensing an incoming acoustic wave producing changes in ambient pressure, said first sensing means including a magnetic diaphragm producing vibrations in response to said changes in ambient pressure due to said incoming acoustic wave and causing changes in ambient magnetic field produced by said vibrations of said diaphragm to move synchronously with said changes in ambient pressure and producing corresponding changes in magnetic flux;
and
second means for sensing said changes in magnetic flux and generating electrical signals representative of said changes in magnetic flux.

Dependencies are inferred from the claim text.

Ultra-broadband hydrophone

Life of this patent

Ultra-broadband hydrophone

Life of this patent

Abstract

Claims9