RU2786039C1 - Method for registering the flow characteristics of a marine object in shallow waters - Google Patents

Abstract

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

Description

The invention relates to the field of hydroacoustics and can be used to record the flow characteristics of a marine object in a shallow water area with an increased level of hydroacoustic interference.

The procedure for registering the flow characteristics of a marine object in a shallow water area consists in fixing the current values of the noise emission signal level of a moving marine object and recording the change in this level over time.

Measurements are made under conditions of background noise in shallow waters, which in real conditions makes it difficult to register the passage characteristics of a marine object, since at a high level of interference, the passage characteristic turns out to be distorted by impulse and noise interference. At the same time, since the registration of small-sized and low-inertia objects is expected in the shallow water area, constant continuous monitoring of the location of the marine object is required using impulse positioning systems and motion elements of the marine object. These systems create additional impulse noise that must be dealt with.

Existing methods for measuring the transmission characteristic involve measurements with the location of the measuring system in the far zone (Fraunhofer) of the acoustic field of a marine object, which is characteristic of the deep sea.

These measurements do not give an adequate picture of the noise emission of low-noise objects in shallow water areas, where they can perform their tasks. Since in the conditions of shallow water areas, the phenomenon of reflection of the noise signal from the boundaries of the acoustic waveguide (the surface and bottom of the sea) and the appearance of imaginary sources of noise emission of a marine object are observed. This leads to the formation of a developed interference structure of the acoustic field within the Fresnel zone, which can have significant dimensions. It is known that the level of interference maxima in the Fresnel zone practically does not change with distance; is the same.

The figure 1 shows the results of numerical simulation of the near Fresnel zones of hydroacoustic emitters of various shapes: a flat round piston (1a) and a flat rectangular piston (1b).

Figure 2 shows the calculation of the acoustic field from a tone signal source in a shallow sea using the RSEMS program for a distance of up to 200 m.

As can be seen from figures 1, 2, when the distance between the emitter and the receiving hydrophone changes within the Fresnel zone, there are practically no changes in the maximum values of sound pressure. A similar picture will be observed at other frequencies.

Therefore, under the conditions of the interference structure of the acoustic field of a shallow water area, measurements of the transmission characteristic in the form of a time diagram of the change in the signal level over time to a single hydrophone are ineffective.

A known method for measuring noise emission in shallow seas using a linear array of hydrophones deployed in the water area.

The complex for measuring the level of underwater noise - the system for measuring the hydroacoustic field (SI GAP) "Neva - IPF" is designed to measure the hydroacoustic fields of surface and submarine ships in running and parking modes in shallow water polygons with depths of up to 300 meters. [Barmak A.S., Korotin P.I., Slizhov A.B., Turchin V.I., Chashchin A.S. Complex for measuring the parameters of the hydroacoustic field SI GAP "Neva-IPF" // Marine Radioelectronics No. 1, 2011]

The purpose of the SIGAP complex "Neva-IPF" is to measure the level of underwater noise of ships in shallow water test sites in the presence of shipping noise. SIGAP "Neva-IPF" uses a linear array of hydrophones deployed in the water area. Interference suppression in the Neva-IPF SIGAP is carried out due to the formation of the directivity characteristic (CH) by a linear array of hydrophones. [Manual for the operation of the complex SI GAP "Neva IPF" - Nizhny Novgorod: IAP RAS, 2006].

It is known that the directivity characteristic (CH) is formed in the far zone (Fraunhofer) of the antenna. At the same time, for the formation of CI at low frequencies, the size of the antenna must be commensurate with the wavelength, which requires its large size.

Therefore, the main disadvantage of SIGAP is that the distance between the antenna and the marine object must ensure that the marine object is located in the far zone (Fraunhofer). It is known [Novikov A.K. Statistical measurements and signal detection. - St. Petersburg: Central Research Institute im. acad. A.N. Krylova, 2006] that the boundary of the far field of the source and antenna is determined by the Fraunhofer zone condition:

,

,

where Da is the size of the antenna;

Du is the size of the radiation source;

λ is the wavelength.

It should be noted that in a shallow water area, reflections of the noise emission signal from the boundaries of the acoustic waveguide (surface and bottom of the sea) lead to the appearance of imaginary radiation sources. This leads to a multiple increase in the size of the radiation source D _u and, as a consequence, to a multiple increase in the Fresnel zone (the interference zone of the acoustic field). In the conditions of a shallow water area (water area depth from several meters to tens of meters) and an interference field (Fresnel zone), the formation of CI will not occur.

Therefore, the disadvantages of this system are that:

- registration of the flow characteristics of a low-noise and small-sized noisy object in shallow water conditions (water area depth from several meters to tens of meters) in the form of a time diagram of signal level changes over time is ineffective.

- low noise immunity under conditions of impulse and spatially correlated and fluctuating noise interference.

A known method for recording noise emission of a low-noise marine object (Patent 2572052 of the Russian Federation, IPC G01S 15/04. Method for registering a low-noise marine object / Kolmogorov BC, Viktorov R.V., Shpak S.A., Omelchenko A.V., Reshetnikov D.S. .; patentee Shpak S.A. - No. 2014119095/28; application 05/12/2014; published 12/27/2015;
bul. No. 36).

The method chosen as an analog eliminates a significant drawback of the methods described above, namely, low noise immunity when used in conditions of non-stationary interference within the registration time of the passage of a marine object.

At the same time, the analogue has significant disadvantages:

- the impossibility of registering the flow characteristic in the form of a time diagram of the change in the signal level over time when using a single non-directional hydrophone in the interference field of a shallow water area;

- reduction of noise immunity when used in conditions of pulsed interference and the presence of random fluctuations in the signal processing path.

The suppression of impulse noise is eliminated by another known method for registering a low-noise marine object using median filtering (Patent 2616357 of the Russian Federation, IPC G01S 15/04. Method for registering a low-noise marine object using median filtering / Ponomarev M.O., Kolmogorov V.S., Shpak S.A., Viktorov R.V. - No. 2016107561; application 03/01/2016; published 04/14/2017; Bulletin No. 11), which is taken as a prototype.

The method for registering a low-noise marine object using median filtering consists in first registering in the receivers a "reference" amplitude-frequency characteristic (AFC) of the noise field of the water space. After that, it is filtered and analog-to-digital conversion is performed in the primary signal processing block, and then used in the block for calculating the cross-correlation function and making a decision of the secondary signal processing block in order to determine and select a pair of receivers with the maximum value of the cross-correlation coefficients between the first and second, first and third, first and N-th receivers. Then the "reference" frequency response is fed to the corresponding inputs of the adaptive filter of the secondary signal processing unit, where the "normalized" frequency response of the noise field of the protected water area is generated. Further, when a low-noise marine object appears in a protected water area in the area of the location of the receiving devices, a “working” frequency response of the water area is formed, which is fed through the previously selected first receiving channel to the first input of the block for calculating the cross-correlation function and decision making, and the first input of the adaptive filter of the secondary block signal processing. If the amplitude of the "working" frequency response of the water space exceeds the developed threshold of the "normalized" frequency response, the frequency response of a low-noise marine object is recorded. In this case, in the first, second and N-th receiving channels of the primary signal processing unit, after performing the analog-to-digital conversion, median filtering is additionally performed by using the corresponding median filters.

This method has significant disadvantages:

- it is ineffective when registering the flow characteristic in the form of a time diagram of the change in the signal level over time when using a single non-directional hydrophone in the interference field of a shallow water area (Fresnel zone);

- reduction of noise immunity when used in conditions of interference in the form of random uncorrelated fluctuations in the signal processing path.

The claimed invention is aimed at eliminating the described shortcomings, the technical task of which is to create a new method for registering the flow characteristics of a marine object in shallow water conditions and the presence of pulsed, spatially correlated and uncorrelated noise interference.

Registration of the flow characteristics in the proposed method is carried out at a fixed curvature of the base of the vertical multichannel antenna array (VMAR). In this case, in the processing circuit (using an adaptive adder) in each VMAP channel, a signal delay is set corresponding to the assumed traverse distance from the marine object to each VMAR electroacoustic receiver (measuring hydrophone), i.e. a base is created for a certain curvature of the front of the received wave from the measured object. After the passage of the marine object, the antenna response is refined according to the actual traverse distance of the VMAR from the marine object by the optimization procedure and finding the maximum of the objective function, i.e. sums from all receivers.

In order to check the possibility of forming an antenna response in the form of a directivity characteristic (CH) in the near zone of a hydroacoustic antenna, simulation modeling was carried out using the C ++ software environment.

Figure 3 shows the simulation results of a multi-element antenna.

Figure 3a shows the calculation of XH (in Cartesian and polar coordinate systems) and the antenna base when the sound source is located in the Fraunhofer zone (far zone). Since the wave front is flat and the antenna base is also flat, the XH is formed. When a sound source is placed in the Fresnel zone, the XN collapses (figure 3b).

As can be seen in figure 3c, the use of the optimization procedure makes it possible to match the antenna base and the wave front (focus on the signal source) and form the HH when the sound source is in the Fresnel zone.

For the optimization procedure, for example, the mathematical software package in the "Mathcad" environment offers two functions - "Maximize" and "Minimize".

Using the "Maximize" function (F, p1, p2, ..., pn), where F is the goal function; p1, p2, ..., pn - variable parameters of the optimization object (sound pressure levels from individual measuring hydrophones VMAP) search for parameters corresponding to the maximum of the function F.

To implement the search algorithm for the maximum value of the sum of signals from individual receiving electroacoustic transducers, at which the antenna response value will be maximum, the built-in function Maximize is used. In this case, the result will be presented as a vector of values at which the objective function reaches its maximum.

In multiparameter optimization, the solution is based on the principle of gradient numerical methods, which consists in successive approximation to the extremum (the maximum value of the sum of signals from individual VMAP measuring hydrophones) by finding the gradient ∇F(p) of the continuously differentiable objective function F(p). It is directed in the direction of the greatest increase in the function at a given point. For example, Mathcad allows you to choose one of three solution algorithms: conjugate gradients, quasi-Newtonian, or Levenberg-Marquard.

To compensate for interference in the method, the following are used:

- median filters (suppression of impulse noise);

- moving average filters (suppression of uncorrelated noise interference);

- adaptive filter (compensation of spatially correlated noise);

Before compensating for spatially correlated interference, impulse noise is suppressed using a median filter and uncorrelated noise interference is suppressed using a moving average filter, both in the primary signal processing unit and in the receiving channel of the reference hydrophones.

To compensate for correlated interference, a signal + interference is received on the VMAR and interference is received on the reference hydrophones of the reference receiving channels located at such a distance as not to receive the signal. The first input of the adaptive filter receives a mixture of signal + noise with VMAR focused on the noise source; the other channel receives interference from one of the reference hydrophones. Before signals are sent from the VMAR and the reference hydrophone, the signals are normalized and centered in order to equalize them in level.

The selection of a reference hydrophone from a set of reference hydrophones for more effective compensation of correlated interference is made according to the criterion of the maximum cross-correlation function for interference between VMAR and reference hydrophones (VMAR and the first reference hydrophone, ... VMAR and the Kth reference hydrophone) Calculation of the cross-correlation function for interference between the measuring hydrophone VMAP and the reference hydrophones is performed in the block for calculating the cross-correlation function and making a decision.

After median filtering, averaging in the moving average filters and adaptive filtering, the signal from the VMAP arrives at the recording device, where the recording takes place:

- throughput characteristic (signal level in time);

- spectrograms of the passage (spectral signal density over time);

- spectrograms of the amplitude envelope (the level and frequencies of the discrete components of the free-blade sound range of the noise emission of a marine object after amplitude detection in time).

Registration of the passage spectrogram (spectral signal density in time) is performed from a single measuring hydrophone VMAP. An example of registering the flow characteristics of a marine object in a shallow water area in the form of a spectrogram is shown in
figure 4.

Figure 4 shows that spatial frequency interference is observed in shallow waters, and the levels of spectral maxima have the same values within the interference zone

As a recording device, a complex for recording and analyzing signals of the Kryakva type can act, which allows recording the listed characteristics of the passage of a marine object simultaneously.

The implementation of the set technical task allows to achieve the following technical result:

- a method has been created for registering the flow characteristics of a marine object in shallow water conditions using VMAR, which makes it possible to increase noise immunity when registering the noise emission of a marine object in shallow water conditions and an increased level of impulse noise from the operation of marine object positioning systems and background noise interference (correlated and not correlated).

A method for recording the flow characteristics of a marine object in a shallow water area, which consists in first recording the level of noise emission of the marine object and background noise of the water area using receivers included in the receiving unit, in order to register the "reference" and "measuring" signal. 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.

The fundamental difference between the claimed method and the prototype is that a vertical multichannel antenna array (VMAR) consisting of N-measuring hydrophones is used as a receiving device of the measuring channel receiving unit, the signals from which are sent in parallel to an additionally introduced adaptive adder for summation and calculation of the maximum objective function (sums of signals), matching and changing the phases of acoustic signals VMAP. 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.

A distinctive feature, the use of VMAR, allows you to use the principles of spatial filtering of the received signals as a result of tuning the antenna array (VMAR) to the front of the received waves resulting from the passage of a moving marine object. Adjustment of the VMAP is carried out as a result of the use of an adaptive adder, which serves for adaptive optimization by calculating the maximum of the objective function (sum of signals), matching and changing the phases of acoustic signals. The result of using VMAP with an adaptive adder is the ability to register the flow characteristics of a marine object in shallow water conditions.

A distinctive feature, the additional use of moving average filters after the corresponding median filters in the primary signal processing unit to perform averaging filtering of the "measuring" and "reference" signals, allows you to level the impact of uncorrelated noise when registering the flow characteristics of a marine object in shallow sea conditions.

The figure 1 shows the results of numerical simulation of the near Fresnel zones of hydroacoustic emitters of various shapes: a flat round piston (1a) and a flat rectangular piston (1b).

Figure 2 shows the calculation of the acoustic field from a tone signal source in a shallow sea using the RSEMS program for a distance of up to 200 m.

Figure 3 shows the simulation results of a multi-element antenna.

The figure 4 shows an example of registering the flow characteristics of a marine object in a shallow water area in the form of a spectrogram.

The proposed method is implemented in a device for recording the flow characteristics of a marine object in shallow waters using a vertical multichannel antenna array. The device diagram is shown in figure 5.

The diagram shows:

1. Receiving unit

1. 1 Vertical multi-channel antenna array (VMAR)

1.1.1 First measuring hydrophone

1.1.N. Nth measuring hydrophone

1.2. First reference hydrophone

1 TO. K-th reference hydrophone

2. Block of primary signal processing

2.1 Measuring receiving channel

2.1.1 Adaptive totalizer

2.1.2 Block of bandpass filters (BPF)

2.1.3 Analog to digital converter (ADC)

2.1.4 Median filter (MF)

2.1.5 Moving Average Filter (MAF)

2.2 First reference receive channel

2.2.1 First block of bandpass filters (BPF)

2.2.2 The first analog-to-digital converter (ADC)

2.2.3 First median filter (MF)

2.2.4 First Moving Average Filter (MAF)

2.K. K-th reference receiving channel

2.K.1 K-th block of band-pass filters (BPF)

2.K.2 K-th analog-to-digital converter (ADC)

2.K.3 K-th median filter (MF)

2.K.4 K-th moving average filter (MAF)

3. Block of secondary signal processing

3.1 Block for calculating the cross-correlation function and making a decision

3.2 Adaptive filter

4. Amplitude detector

5. Recorder

All structural elements in the receiving unit 1, in the primary signal processing unit 2, in the secondary signal processing unit 3, as well as the amplitude detector 4, the recording device 5 are electrically connected.

In the vertical multichannel antenna array 1.1, identical measuring hydrophones 1.1…1.N are used, the output of each of which is connected in parallel to the input of the adaptive adder 2.1.1, which transmits the received signal to the input of the bandpass filter block 2.1.2 and then to the input of the analog-to-digital converter 2.1.3, the output of which is fed to the input of the median filter 2.1.4, from the output of the median filter 2.1.4 to the moving average filter 2.1.5, with subsequent transmission to the first input of the adaptive filter 3.2 and to the input of the block for calculating the cross-correlation function and acceptance solutions 3.1 of the secondary signal processing unit 3.

Measuring hydrophone 1.N from the VMAR (as close as possible to the depth of passage of the marine object) is connected to the input of the recording device 5.

The output of each corresponding identical reference hydrophone 1.2...1.K of the receiving unit 1 is connected in series with the input of the corresponding block of band-pass filters 2.2.1...2.K.1, the output of which is connected to the input of the corresponding analog-to-digital converter 2.2.2... 2.K.2, its output is connected in series with the corresponding input of the median filter 2.2.3 ... 2.K.3, the outputs of the corresponding median filters are connected in series with the input of the corresponding moving average filter 2.2.4 ... 2.K.4. Then the signal from the output of each moving average filter 2.2.4 ... 2.K.4 is fed to the corresponding inputs of the block for calculating the cross-correlation function and making a decision 3.1 of the secondary signal processing block 3.

Output of the block for calculating the cross-correlation function and making a decision 3.1. is connected in series to the second input of the adaptive filter 3.2, the output of the adaptive filter 3.2 is connected in parallel to the input of the amplitude detector 4 and then to the input of the recording device 5. The output of the amplitude detector 4, in turn, is connected to the input of the recording device 5.

Implementation of the method

To implement the claimed method, the device for recording the flow characteristics of a marine object in a shallow water area is equipped with a conventional portable or stationary power source located on a shore post or a floating carrier.

The vertical multichannel antenna array 1.1 uses identical measuring hydrophones 1.1.1...1.1.N with the ability to receive acoustic signals in the aquatic environment, the output of each of which is connected in parallel to the input of the adaptive adder 2.1.1, which is used to calculate the maximum objective function (sum of signals) matching and changing the phases of acoustic signals for subsequent transmission to the input of the bandpass filter block 2.1.2 for the possibility of passing the transmitted electrical signal of the optimal frequency band and transmitting to the input of an analog-to-digital converter 2.1.3 for converting the signal from analog to digital form, the output of which is connected to the input of the median filter 2.1.4 to eliminate impulse noise, which in turn is connected to the moving average filter 2.1.5, used to reduce the level of fluctuations by smoothing incoherent noise, then connected to the first input of the adaptive filter 3.1. Before a signal is sent from the measuring receiving channel, the signal is normalized and centered in order to equalize them in terms of level.

One of the measuring hydrophones 1.1.N from the composition of the VMAP (as close as possible to the depth of the passage of the marine object) is connected to the input of the recording device 5 to display the spectral density of the noise emission (spectrogram of the passage) of the marine object.

The output of each corresponding identical reference hydrophone 1.2…1.K of the receiving unit 1 is connected in series with the input of the corresponding bandpass filter unit 2.2.1…2.K.1 to enable transmission of the transmitted electrical signal of the optimal frequency band, the output of which, in turn, is connected to the analog input -digital converter 2.2.2 ... 2.K.2, the outputs of which are connected to the inputs of the median filters 2.2.3 ... 2.K.3, to eliminate impulse noise, the outputs of these median filters are connected in series with the input of the corresponding moving average filter 2.2.4 …2.K.4 to reduce the level of fluctuations by smoothing out incoherent noise. Then the output of each moving average filter 2.2.4 ... 2.K.4 is connected in parallel with the corresponding inputs of the cross-correlation function calculation and decision block 3.1 of the secondary signal processing block 3. Before the signals are sent from the reference receiving channels, the signal normalization and alignment procedure is performed to level them up.

In the block for calculating the cross-correlation function and making a decision 3.1, a pair of receiving channels (measuring and reference) is calculated and determined with the maximum value of the correlation coefficients between the measuring channel and the first reference receiving channel, ... the measuring channel and the K-th reference receiving channel. Depending on the calculated value, the corresponding output of the moving average filter of the reference receiving channel 2.2.4 ... 2.K.4 is connected in series through the block for calculating the cross-correlation function and making a decision 3.1 to the second input of the adaptive filter 3.2, at the output of the adaptive filter 3.2 a flow characteristic is formed of a marine object, which is simultaneously fed to the input of the recording device 5 to display the time diagram of the passage and to the input of the amplitude detector 4, in order to isolate the amplitude modulation of the envelope of the passage characteristic of the marine object. The output of the amplitude detector 4, in turn, is connected in series with the input of the recording device 5 to display the discrete components that have arisen during the passage of a marine object.

The claimed method is of considerable interest to the national economy, since the device implemented by this method ensures the protection of biological marine objects. The claimed solution does not adversely affect the ecological state of the environment.

Thus, the claimed "Method for recording the flow characteristics of a marine object in shallow waters" using VMAP is a method for assessing the noise emission of marine objects and for maintaining the acoustic quality of marine objects in shallow waters with a high level of industrial and natural noise background.

The claimed method has the following advantages:

- the possibility of registering the passage characteristics of a marine object in the conditions of the Fresnel interference zone;

- increasing the noise immunity of the means of registering the passage characteristics of a marine object by increasing the signal level when using VMAR and suppressing impulse, correlated and uncorrelated interference;

- control of the level of discrete components of the VLZR and the dynamics of their frequency change.

The claimed method is industrially applicable, since widely used components and products of the radio engineering industry and computer technology are used for its implementation.

Claims (1)

A method for recording the flow characteristics of a marine object in a shallow water area, which consists in first recording the level of noise emission of the marine object and background noise of the water area using receivers that are part of the receiving unit, in order to register the "reference" and "measuring" signals, after this, bandpass 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 with the maximum value of the cross-correlation coefficient between the measuring receiving channel is determined and the first reference receiving channel, ... the measuring receiving channel and the 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 adaptive filtering is performed, the received signal is used in the recording device to register the flow characteristics of the marine object, as well as in the amplitude detector for isolating and further recording the discrete components of the shaft-bladed sound range of a marine object, characterized in that a vertical multichannel antenna array (VMAR) is used as a receiving device of the receiving unit for the measuring channel, consisting of N measuring hydrophones, the signals from which are sent in parallel to an additional the introduced adaptive adder, which is used to calculate the maximum objective function (sum of signals), match and change the phases of acoustic signals VMAP, and after median filtering in the block of primary signal processing, averaging th filtering of "measuring" and "reference" signals by means of additionally introduced moving average filters.

Images