METHOD OF MEASURING DISTANCE TO MONITORED FACILITY Russian patent published in 2012 - IPC G01S15/08 

FIELD: physics.

SUBSTANCE: periodic pulsed acoustic signal is generated at the monitored facility using a vertically aligned four-module antenna whose modules are arranged in pairs symmetrically about the surface of the sea bed, wherein the top and bottom modules are excited in antiphase with respect to the other two modules lying in between them. The antenna is mounted at the sea bed. Antenna emission is synchronised with zero time at the reception point on the monitored facility. The acoustic signal is received at the monitored facility using two receivers. One of the receivers lies directly on the ground and is a vector receiver at whose output the vertical and horizontal components of the oscillating velocity vector are measured. The second receiver is a directional acoustic pressure receiver. Group lag time is determined from the measured parameters while preliminarily determining time intervals. The yaw angle at the reception point is determined based on the measured values of the component of the oscillating velocity vector. The unknown distance to the monitored facility is calculated using invariant speed equal to the speed of the bottom wave and the group lag time.

EFFECT: reduced measurement error.