METHOD FOR MEASURING DISTANCE TO MOVING UNDERWATER OBJECT Russian patent published in 2021 - IPC G01S15/08 G01S15/34 G01S15/58 G01S7/52 

FIELD: hydroacoustics.

SUBSTANCE: invention relates to hydroacoustics and can be used in the development of hydroacoustic rangefinder systems designed to operate in a shallow sea with large dispersion distortions of the acoustic signal. According to the method, a periodic pulsed acoustic chirp signal is generated and emitted at the monitoring object by a radiator installed at the bottom. The radiation is synchronized with the beginning of the countdown on the moving controlled object. At the monitored object, the signal is received by a combined receiver installed in the fairing. According to the measured parameters of the acoustic signal at the controlled object, the group delay time is determined as a time point corresponding to the maximum of the cross-correlation function between the pre-recorded electronic copy of the emitted sound pressure signal and one of the received signals in the vector channels of the combined receiver, which corresponds to the maximum value of the maximum of the cross-correlation function. In addition, the measured values of the cross-correlation functions determine the slip angle and the phase velocity, and also determine the invariant velocity equal to the velocity of the inhomogeneous wave corresponding to zero reflection coefficient of the water - seabed interface. The desired distance to the controlled object is calculated using the thus determined invariant velocity, group delay time and phase velocity.

EFFECT: reduction of the error in measuring the distance to the controlled object.

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