METHOD FOR REGISTERING THE FLOW CHARACTERISTICS OF A MARINE OBJECT IN SHALLOW WATERS Russian patent published in 2022 - IPC G01S15/04 

FIELD: hydroacoustics.

SUBSTANCE: invention relates to the field of hydroacoustics, namely to a method for registering the passage characteristics of a marine object in a shallow water area in a wide frequency band, and can be used in measuring the primary hydroacoustic field of marine objects under conditions of non-stationary interference within the registration time of the passage of a marine object and an increased level of random emissions background noise of the shallow marine area. In the method for registering the passage characteristic of a marine object in a shallow water area, first, the noise level of the marine object and the background noise of the water area are recorded using receivers that are part of the reception unit in order to register the "reference" and "measuring" signals. After that, band-pass filtering, analog-to-digital conversion, median filtering are performed in the primary signal processing block, and then used in the cross-correlation function calculation and decision block of the secondary signal processing block, where a pair of receiving channels is determined with the maximum value of the cross-correlation coefficient between the measuring receiving channel and the first reference receiving channel, … measuring receiving channel and K-th reference receiving channel. Then the selected pair of channels of the primary signal processing unit is used to supply "measuring" and "reference" signals to the corresponding inputs of the adaptive filter of the secondary signal processing unit. After performing adaptive filtering, the received signal is used in a recording device for recording the passage characteristics of a marine object, as well as in an amplitude detector for separating and further recording discrete components of the shaft-blade sound row of a marine object. At the same time, a vertical multichannel antenna array (VMAA) is used as a receiving device for the measuring channel, consisting of N measuring hydrophones, the signals from which are sent in parallel to an additionally introduced adaptive adder, which serves to adjust the VMAA by calculating the maximum of the objective function (sum of signals), matching and changing the phases of acoustic signals. Also, after the median filtering in the primary signal processing block, the averaging filtering of the "measuring" and "reference" signals is performed by means of additionally introduced moving average filters.

EFFECT: invention provides the possibility of registering the flow characteristics of a marine object in shallow water conditions, increasing noise immunity when registering the noise emission of a marine object and simultaneously suppressing both impulse noise, spatially correlated noise, and incoherent components of random noise present in shallow water area.

1 cl, 5 dwg