ACOUSTIC FIBER-OPTIC ANTENNA Russian patent published in 2004 - IPC

FIELD: systems of remote measurement of static and acoustic pressure, reception and direction finding of noise and echo ranging signals of audio, bass and infrasonic frequencies in sonic systems and seismic prospecting, in guard systems of objects on land and in aqueous medium.

SUBSTANCE: the acoustic fiber-optic antenna for the Fresnel's diffraction zone placed in a gaseous atmosphere or aqueous medium has an optical channel consisting of input and output multimode FLC and similar light conduits connected to them and FOS of the microbending type distributed along them, a second additional optical channel is used, FOS without microbends are located in the first channel, and in the second FOS-channel with microbends preliminarily made in them the input FLC of the first sensors of each channel are connected to a directional coupler, and the output FLC of the last FOS of each channel are connected to separate photodetectors, whose outputs are connected to the inputs of a differential amplifier.

EFFECT: reduced optical loss with growth of intensity of the acoustic signal due to the use of the additional second channel, provided summation of the output signals of two measuring channels.

3 cl, 1 dwg