METHOD FOR PASSIVE ACOUSTIC DETERMINATION OF THE LOCATION OF A DIVER Russian patent published in 2020 - IPC G01S15/00 

FIELD: hydro acoustics.

SUBSTANCE: invention relates to passive hydroacoustic detection and underwater navigation, specifically to passive methods of acoustic detection and location of divers and underwater swimmers in water, and can be used in underwater search and rescue diving operations. Method includes registration of underwater noise of the water area in the frequency band below 1,000 Hz by at least two acoustic sensors with known coordinates and depth and an acoustic sensor of a diver installed with the possibility of recording its respiratory noises. Obtained noise signal is processed to extract quasi-periodic variations of the noise intensity, the frequency of which lies in range of 0.1–1 Hz. Calculating a cross-correlation function between the response of the acoustic sensor of the diver and the responses of the surrounding sensors of the acoustic sensors and determining the delay time for reaching the maximum of the cross-correlation functions, which then calculates distance to diver from each of remote acoustic sensors and range-finding method for intersection of spheres determine location of diver in space.

EFFECT: high accuracy of determining location of a diver and resolution of location of 2 and more divers.

1 cl, 2 dwg