METHOD OF EQUIPPING TRAL WITH ACOUSTIC INSTRUMENTS WHEN WORKING IN NEGATIVE REFRACTION CONDITIONS OF ACOUSTIC VIBRATIONS Russian patent published in 2017 - IPC A01K73/00 G01B17/00 

FIELD: physics.

SUBSTANCE: method involves the installation of a central trawl transmitter on the upper selection of the trawl and the transceiver units on one of the trawl warps with the direction of their emission towards the vessel. Each subsequent unit from the central trawl transmitter is fixed with the possibility of being located at shallower depths relative to each other, remaining in the zones of acoustic illumination crossing the trawl warp. When transmitting control signals from the vessel to the trawl system, the transmitting and receiving units synchronize the radiation direction from each subsequent unit to greater depths relative to each other, also remaining in the zones of acoustic illumination crossing the trawl warp.

EFFECT: method allows to create a stable acoustic connection during fishing, under conditions of vertical temperature fluctuations, creating a negative refraction.

2 dwg