RU193838U1 - HYDROACOUSTIC DEVICE FOR MEASURING DISPLACEMENT OF A POWER AREA REGARDING THE BOTTOM - Google Patents

Abstract

The utility model relates to the field of hydroacoustic technology, in particular to hydroacoustic navigation devices, and can be used to hold the craft at a point and position during missions by various submarines, submarines, when working with drifting ice, etc. The objective of the utility model is to accurately measure the displacement of the watercraft using the antenna array of the receiving hydrophones with the maximum use of domestic integrated circuits of operational amplifiers, analog-to-digital converters, programmable logic integrated circuits, and digital signal processing circuits. receiving flat square equidistant antenna array of hydrophones and domestic Tween integrated circuits. 3 ill.

Description

The utility model relates to the field of hydroacoustic technology, in particular to hydroacoustic navigation devices, and can be used to hold the craft at a point and position during missions by various submarines, submarines, when working with drifting ice, etc.

It is known to build such sonar devices with bottom beacons transponders (DMO) to keep the craft at a point and positioning. The devices consist of parts - several DMOs installed at the bottom of the vessel by the director and the interrogation and reception part placed on the ship. Communication between parts by means of a hydroacoustic communication channel. The main technical characteristics are given, for example, in [1, 6].

The main disadvantage of these devices is the need to put on the bottom of the DMO.

Devices with receiving flat square equidistant antenna arrays (AR) of hydrophones when using the emitter of a standard marine echo sounder, ensuring a normal sound fall to the bottom, are free from this drawback. The devices “Plast”, “Plast-2”, “Maple”, “Pomegranate” and operated on research vessels had a similar construction. The devices are intended for measuring in the horizontal plane various correlation characteristics of echo signals from the bottom and the variability of the amplitude of echo signals from the bottom at the aperture of the AR, obtaining the general relief of the bottom and other oceanological measurements, as well as the search and exploration of ferromanganese nodules ("Garnet"). The main characteristics of the devices are 64 ... 256 AP hydrophones, relatively low operating frequencies of 1 ... 30 kHz [2].

The disadvantage of these devices is the bulkiness of the components (the dimensions of the Plast-2 3 × 3 m, the Grenade 4.2 × 4.2 m), the presence of a winch for immersing the AR, the processing of echo signals from the bottom on a ship computer not in real time, and energy intensity and high cost, which is associated with orientation to ocean depths of up to 6000 m, large vessels, i.e. experimental, research nature of devices.

Such devices with correlation processing of echo signals from the bottom at the aperture of the AR include compact hydroacoustic correlation speed meters (logs) of a watercraft. The RD Instruments correlation lag uses a flat AR of 8 hydrophones with a non-equidistant arrangement for emitting 7 hydrophones and receiving echo signals from the bottom. Operating frequency 22 kHz. Structurally, hydrophones and electronic components are placed in a cylindrical body with a diameter of 46 cm [3].

The closest analogue to the proposed utility model is the compact device of the correlation lag COVELIA firms Scientific Scientific and Chelsea Technologies, which is designed for placement on submarines and submarines. Operating frequency 60 kHz, filling pulses of radiation with a phase-shifted code. The speed is measured by the one-dimensional correlation processing of the echo signals from the bottom at the AR aperture. A flat AP with a size of 330 × 220 × 70 mm has receiving hydrophones emitting and with an unequal arrangement. The device uses operational amplifiers (op amps), analog-to-digital converters (ADCs), programmable logic integrated circuit (FPGA) and integrated circuit (IC) digital signal processing (DSP). Electronics is made on 4 printed circuit boards placed in a cylindrical case with a diameter of 100 mm, 230 mm long, power supply - a 24-volt battery with a capacity of 3.0 Ah. Correlation processing of echo signals from the bottom and delivery to the consumer of speed values in real time [4, 5].

The disadvantage of the prototype is the non-equidistant arrangement of the receiving hydrophones AR, i.e. spatial two-dimensional (in two mutually perpendicular directions) cross-correlation of two “slices” of the acoustic field at the aperture of the receiving hydrophones of the AR has uneven spatial discreteness, which leads to a decrease in the accuracy of measuring the position of the maximum cross-correlation and, as a result, to a decrease in the accuracy of measuring the displacement of the vehicle.

The objective of the utility model is to more accurately measure the displacement of the craft by means of a receiving flat square equidistant AR of hydrophones.

To solve the problem in a hydroacoustic device for measuring the displacement of the boat relative to the bottom, consisting of a series-connected emitting hydrophone, a power amplifier, a master oscillator, as well as a programmable logic integrated circuit connected to a power amplifier, a master oscillator, and also series-connected receiving hydrophones, operational amplifiers, analog-to-digital converters, and operational amplifiers, analog-to-digital converters are connected to a programmable logic integrated circuit, the latter is connected to the digital signal processing integrated circuit, the latter is connected to the consumer of the measured displacement of the watercraft, a new feature has been introduced, namely: receiving hydrophones are arranged as a flat square equidistant AR.

The technical result consists in increasing the accuracy of measuring the displacement of the craft relative to the bottom, which is provided by the receiving flat square equidistant AR hydrophones.

The technical result is achieved due to the uniform discreteness of the spatial two-dimensional cross-correlation of two "slices" of the acoustic field.

The essence of the utility model is illustrated in FIG. 1-3, where in FIG. 1 shows an enlarged diagram of the claimed device (dashed circles around the individual parts of the claimed device), FIG. 2 shows volumetric and in FIG. 3 in the form of isolines, the image of the coefficient module of the uniform discrete spatial two-dimensional cross-correlation of two “slices” of the acoustic field.

The claimed device (Fig. 1) contains a serially connected radiating hydrophone 1, a power amplifier 2, a master oscillator 3, and also a programmable logic integrated circuit 7 connected to a power amplifier 2, a master oscillator 3, as well as a series-connected receiving plane square equidistant AR hydrophones 4, operational amplifiers 5, analog-to-digital converters 6, and operational amplifiers 5, analog-to-digital converters 6 are connected to a programmable logic integrated circuit 7, which is integrated with an integrated circuit for digital signal processing 8, the latter is connected to the consumer of the measured displacement of the craft. The radiating hydrophone 1 and the receiving flat square equidistant AR of hydrophones 4 are a structurally separate part of the device, and all other listed elements are another structurally separate part of the device, parts of the device are interconnected by a multicore cable.

A possible implementation of a device placed, as an example, on a watercraft for operation at depths of up to 500 m (shelf areas) and having 8 × 8 = 64 hydrophones of a receiving flat square equidistant AR, is as follows.

Then, the operating frequency of 50 kHz corresponds to the accepted choice for marine echo sounders with a maximum measured depth of 500 m [6]. The radiating hydrophone 1 and 64 of the hydrophone of the receiving flat square equidistant AR 4 can be borrowed from the device NEL-1000-3 sounder (St. Petersburg, NTP "Navi-Dals"). NEL-1000-3 hydrophones have the following parameters:

- frequency F = (50 ± 1.5) kHz;

- bandwidth ΔF = 7.5 kHz;

- active resistance Rw = (118 ± 5) ohms;

- sensitivity in the radiation mode Ssl = (160 ± 30) Pa⋅m / V;

- the width of the directivity characteristic θ _хн = (30 ± 5) °;

- sensitivity in reception mode Spr = (550 ± 50) Mkv / Pa;

- capacitance 30 nF;

- diameter 80 mm.

The size of the receiving flat square equidistant AR 4 is not more than 750 × 750 × 100 mm with a distance between adjacent hydrophones of 90 mm, which provides a measurement of displacement of less than ≈90 mm.

Power amplifier 2 can be made as a key resonant bridge amplifier on four bipolar transistors with an isolated gate, for example, KP829G (Ulyanovsk, Iskra Design Bureau), and a matching circuit with a radiating hydrophone 1 at the output. The radiation power is set by the supply voltage.

The master oscillator 3 should then produce a sawtooth voltage phase-shifted 180 °. Implementation - integrated circuits of a pulse-width modulation controller, for example, 1156ЕУ2А (Bryansk, CJSC Silicon EL Group), and two control integrated circuits (drivers), for example, 1308EU (Bryansk, CJSC Silicon EL Group).

Operational amplifiers 5 in the amount of 64 and 64 analog-to-digital converters 6 can be performed on programmable integrated circuits of the 5400 series (Moscow, Zelenograd, Soyuz Design Center JSC). For example, the 5400TP064 integrated circuit can be programmed with 86 different operational amplifiers, with 6 12-bit synchronous analog-to-digital converters with a maximum sampling frequency of 500 kHz. The 5400TP045 integrated circuit uses the same function blocks, but their number is reduced. As a result, the chip has a more compact body.

Programmable logic integrated circuit 7 can be from a series 5578TC (Voronezh, JSC “Voronezh semiconductor devices-assembly plant”).

As an integrated circuit for digital signal processing 8, you can use 1892 VM3T (Moscow, Zelenograd, JSC SPC ELVIS) with a capacity of 240 MFlops, the core of the central processor is the leading in a dual-processor configuration.

The radiating hydrophone 1 and the receiving flat square equidistant AR of hydrophones 4 are structurally separate part, all the other listed elements are like another structurally separate part of the device on several (5 ... 6) 6U boards Euromechanics 233 × 160 × 40 mm in size, for example, in the form of a one-story instrument hinged cabinet of small size and weight.

The use of integrated circuits 1156ЕУ2А, 1308ЕУ, 1892 ВМ3Т and from the 5400, 5578TC series fits into the concept of creating signal processing systems in sonar based on domestic microelectronics.

The claimed device operates as follows.

The integrated circuit for digital signal processing 8 receives from the consumer the measured displacement of the watercraft, for example, a navigation complex, a dynamic positioning system or an information-control system, the depth value and calculates the timing diagram of radiation and reception, gain, level of radiated power. At shallow and medium depths, a pair of pulses are emitted. At shallow depth, the next pulse is emitted after receiving the echo signal. At medium depths, echo signals are received after the end of emission of a pair of pulses. At great depths, one pulse is emitted and the reception of the echo signal after the end of the radiation. The generated time diagram of radiation and reception, gain, emitted power level is translated into a programmable logic integrated circuit 7 and then to a master oscillator 3, power amplifier 2, operational amplifiers 5, analog-to-digital converters 6. According to the time diagram, radiation and reception begin. Amplified by operational amplifiers 5 and digitized values (discrete samples) by analog-to-digital converters 6 at a sampling frequency of 50 * 4 = 200 kHz of received echo signals from 64 channels of a receiving flat square equidistant AR, they are processed by a programmable logic integrated circuit 7. Obtaining low-frequency quadrature components (mathematically conjugated according to Hilbert, a typical procedure for digital processing of strip echoes from the bottom) begins by multiplying the discrete samples of the received echo ov for discrete samples of the functions sin (2 * 3.14159 * 50,000 * 0.005 * 0.001 * k) and cos (2 * 3.14159 * 50,000 * 0.005 * 0.001 * k), k = 0, 1, 2, 3 - numbers of samples taking into account the periodicity functions. Next, digital filtering is performed using low-pass filters with a band of 0 - 1000 Hz, implemented by filters with a finite impulse response. The output samples of the low-pass filters are decimated with a coefficient of 40, i.e. the samples of the low-frequency quadrature components have a tempo of 0.2 ms, and are translated into an integrated circuit for digital signal processing 8.

The determination of the coefficient of discrete two-dimensional spatial cross-correlation for two "slices" of the acoustic field at adjacent time instants (CEC) is carried out by an integrated circuit for digital signal processing 8 for a receiving flat square equidistant AR of hydrophones according to the mathematical expression [2]

- квадратные матрицы модулей низкочастотных квадратурных составляющих отсчетов поля для двух моментов времени, полученные от программируемой логической интегральной схемы 7, N=64 - число гидрофонов приемной плоской квадратной эквидистантной АР, m, n - сдвиг одной реализации относительно другой по осям х и у, выраженный в единицах расстояния между соседними гидрофонами 90 мм,where a _ij and

- the square matrix of modules of the low-frequency quadrature components of the field samples for two time instants obtained from the programmable logic integrated circuit 7, N = 64 - the number of hydrophones of the receiving flat square equidistant AR, m, n - the shift of one implementation relative to the other along the x and y axes, expressed in units of distance between adjacent hydrophones 90 mm,

Post-correlation processing (determining the maximum position of the KVK module, bias values, and translation to the consumer) is performed by the digital signal processing integrated circuit 8. The position of the maximum m _m and n _{m of} the KVK module is determined by extreme correlation methods using interpolation algorithms, for example, [7]. From the found values of m _m , n _m and the distance between adjacent hydrophones 90 mm, the values of the displacement of the watercraft Δх / 2 and Δу / 2 are determined, which are transmitted to the consumer of the measured displacement of the watercraft.

To illustrate the utility model of FIG. Figures 2 and 3 show the results of semi-natural modeling of processing according to (1) - (5) on an office computer in the MATLAB environment. FIG. 2 is a three-dimensional image and FIG. 3 - isolines of the KVK module r (m, n) of two “slices” of the acoustic field, taken synchronously at each time point at 8 × 8 of the receiving flat square equidistant AR of hydrophones. From consideration of FIG. Figure 3 shows that the shift in the maximum of the KVK module along the abscissa is Δх≈0 and along the ordinate is Δу≈-20 cm, but the shift of the craft is Δу / 2≈-10 cm.

The technical result is achieved due to the uniform discreteness of the spatial two-dimensional cross-correlation of two “slices” of the acoustic field, which is ensured by the receiving flat square equidistant AR of hydrophones.

Information sources

1. Koryakin Yu.A., Smirnov S.A., Yakovlev G.V. Ship sonar equipment. St. Petersburg: Science, 2004.

2. Volovov V.I. Reflection of sound from the bottom of the ocean. M .: Nauka, 1993.

3. G. Griffiths, S.E. Bradley, "A correlation speed log for deep water", Sea Technology, 39 (3), pp. 29-35.1998.

4. Phillips B., Robinson H., Hill M., "On the development of a correlation sonar velocity log", International Unmanned Undersea Vehicles Symposium, Naval Undersea Warfare Center, Newport, U.S.A., April 24 - 27,2000.

5. Boltryk P., Hill M., Keary A., Phillips B., Robinson H., White P., "An ultrasonic transducer array for velocity measurement in underwater vehicles", Ultrasonics, 42, 2004,473-478.

6. Bogorodsky A.B., Yakovlev G.V., Korepin E.A., Dolzhikov A.K. Hydroacoustic technology for research and development of the ocean. L .: Gidrometeoizdat, 1984.

7. Baklitsky V.K., Yuryev A.N. Correlation-extreme navigation methods. M .: Radio and communication, 1982.

Claims (1)

A hydro-acoustic device for measuring the displacement of the boat relative to the bottom, containing a serially connected emitting hydrophone, a power amplifier, a master oscillator, as well as a programmable logic integrated circuit connected to a power amplifier, a master oscillator, as well as serially connected receiving hydrophones, operational amplifiers, analog-to-digital converters, and operational amplifiers, analog-to-digital converters are connected to a programmable logic integrated circuit, which connected to an integrated circuit for digital signal processing, the latter is connected to the consumer of the measured displacement of the craft, characterized in that the receiving hydrophones are arranged in the form of a flat square equidistant antenna array.

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