RU2483326C2 - Hydroacoustic synchronous range-finding navigation system for positioning underwater objects in navigation field of randomly arranged hydroacoustic transponder beacons - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: hydroacoustic synchronous range-finding navigation system, having a bottom navigation base consisting of M hydroacoustic transponders with different response frequencies f_m (m=1-M), a clock-pulse generator and an acoustic transmitter with sampling frequency f₀ mounted on the navigation object, the input of the acoustic transmitter being connected to the first output of the clock-pulse generator. An M-channel receiver for receiving response signals with frequencies f_m, M devices for measuring time of propagation of acoustic signals to the transponder, operating at the frequency of that channel, and back, first inputs of which are connected to outputs of the M-channel receiver, and second inputs are connected to second outputs of the clock-pulse generator, M×N units for converting time intervals to distance based on the number N of possible beam paths, inputs of which are connected to outputs of corresponding devices for measuring propagation time, M units for selecting maximum distance, inputs of which are connected to outputs of N units for converting time intervals to distance of the given channel, a navigation object coordinate computer, the first input of which is connected to outputs of M units for selecting maximum distance, an additional second bottom navigation base consisting of M hydroacoustic transponder beacons with different radiation frequencies F_m (m=1-M), which are mechanically connected to corresponding M transponder beacons, having M synchronously operating clock-pulse generators, M transmitters with different operating frequencies F_m, the inputs of which are connected to outputs of clock-pulse generators, M hydroacoustic radiators with operating frequencies F_m, inputs of which are connected to outputs of transmitters with corresponding operating frequencies; the navigation object is additionally fitted with a second clock-pulse generator which operate synchronously with the clock-pulse generators of the transponder beacons, the first output of which is used to synchronise the M synchronously operating clock-pulse generators of the hydroacoustic transponder beacons before mounting at the bottom, a trailing receiving acoustic antenna, a second M-channel receiver for receiving acoustic signals of transponder beacons, the input of which is connected to the output of the trailing receiving acoustic antenna, M devices for measuring time of propagation of acoustic signals from the transponder beacons to the navigation object, first inputs of which are connected to outputs of the second M-channel receiver, and second inputs are connected to the second output of the second clock-pulse generator, additional M units for converting time intervals to distance, inputs of which are connected to outputs of M devices for measuring time of propagation of acoustic signals from the transponder beacons to the navigation object, and the outputs are connected to second inputs of the navigation object coordinate computer, wherein the M hydroacoustic radiators of the transponder beacons and the trailing receiving acoustic antenna lie near the seabed at a distance not greater than the wavelength at operating frequencies F_m, and the additional M units for converting time intervals to distance calculate the desired distances r_m through propagation times t_m, characterised by that the additional second bottom navigation base consisting of M hydroacoustic transponder beacons with different radiation frequencies F_m (m=1-M), mechanically connected to corresponding M transponder beacons, is also electrically connected to the same corresponding transponder beacons; the navigation object is also fitted with a receiver-indicator for receiving satellite signals, the first receiving antenna of which is mounted on its housing, and the second receiving antenna is mounted on a unit for counting displacements of the conducting rope which connects the navigation object with the trailing receiving acoustic antenna, and another n receiving antennae are mounted on transponder beacons of the additional second bottom base; M hydroacoustic transponders are provided with a ballast anchor with a hydroacoustic release; the antenna of the M-channel receiver has a cylindrical shape and is made from M hydrophones which form in the horizontal plane two navigation bases for detecting acoustic signals, wherein the lateral and rear directions are blinded by shields, M transponder beacons of the first and second bottom base, the navigation object is provided with sensors for measuring sound speed in water, hydrodynamic pressure and orientation.

EFFECT: longer range without increase in error when determining coordinates of a navigation object.

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Description

The invention relates to the field of sonar navigation systems and can be used for navigation support of underwater vehicles operating in ice conditions, making it difficult for the supply vessel to access them, and can also be used for seismic and geological exploration on the seabed using towed or remote-controlled underwater vehicles .

Acoustic navigation systems with an ultrashort base are produced by a significant number of companies for various applications - from the positioning of scuba divers in shallow water to the location of objects at great depths and ranges. The most famous are the sonar navigation systems of IXSEA, SIMRAD, SONARDYNE, KONGSBERG, GeoAcoustics. Typical characteristics of systems of medium range up to 3 km have frequencies in the range of 20-30 kHz, accuracy is a few percent of the inclined range. Long-range systems of the order of 10 km operate in the frequency range 10-15 kHz, the claimed navigation accuracy of some systems reaches 0.1% of the inclined range. The most widely used are two navigation systems such as POSIDONIA and HIPAP-500. The first uses complex signals and, due to this, has an improvement in the signal-to-noise ratio compared to 19 dB tone bursts. Currently, the claimed accuracy is 0.3% slant range. The second is a powerful phased antenna, consisting of hundreds of independent receivers, which, according to the manufacturer, has redundancy in the number of receivers, computing tools and software. The claimed accuracy is 0.1% of the inclined range, the viewing angle is 200 degrees in the vertical plane. The acoustic data acquisition system of this system is not inferior to data acquisition systems, for example, high-resolution multi-beam echo sounders, but it has a high cost.

Known acoustic navigation systems using the principle of ultrashort base, determine the spatial position of the positioned object by measuring the travel time and direction of arrival of the acoustic waves emitted by the beacon installed on this object using a multi-element receiving antenna. The measured travel time is recalculated taking into account the profile of the speed of sound in an inclined range, and the direction of arrival of the wave on the surface of the antenna, taking into account the slopes and azimuth of the antenna itself, allows you to determine the point from which the sound was generated. The measurement of travel time is carried out by analyzing the shape of the received sound signal, while the accuracy of the time measurement is determined by the bandwidth of the receiving path and the signal-to-noise ratio. The direction of arrival of the sound wave in UHF systems is determined by measuring the phase difference of the signals received by different hydrophones, followed by the conversion of the phase difference into geometric angles, taking into account the characteristic wavelength of the acoustic signal and the spatial diversity of the receivers. The accuracy of the direction measurement is determined by the distance between the receivers and the signal-to-noise ratio. The accuracy of measuring the travel time, or, in other words, the accuracy of determining the position of an object along a beam, does not depend on distance (at a sufficiently high signal level compared to noise) and for traditional long-range systems is a fraction of a meter. With a fixed angular resolution, the error in measuring the position of the object across the beam increases linearly with distance and, as a rule, is characterized as a percentage of the slant range. The best examples of UKB systems have an angular accuracy of the order of 0.1%, which at a distance of about 5 km corresponds to an accuracy across the beam of 5 m. Since the ultimate goal of using any navigation system is to determine the geographical coordinates of the object, angular resolution is the main characteristic of the UKB system.

The technical essence of the known sonar systems for providing underwater navigation is described in the sources of patent information (patents RU No. 2084924 [1], RU No. 2084923 [2], RU No. 2289149 [3], RU No. 34020U [4], RU No. 2158431 [5] , RU No. 23038454 [6], RU No. 2038127 [7], copyright certificate SU No. 713278 [8], RU No. 2365939 [9], RU No. 2371738 [10], WO No. 0123908 A1, 04/05/2001 [11] and in the technical literature: Milne P.Kh. Hydroacoustic positioning systems. - L .: Shipbuilding, 1989, p. 49-60 [12] and others).

The closest in essence to the claimed object of technology are devices described in the patent descriptions [3] and [8] and in the source [12].

Known sonar synchronous rangefinder navigation system [12], consisting of a base of sonar transponders, used to measure the propagation time of acoustic signals from the navigation object to the beacons, a distance calculation device from the measured propagation time and a known sound speed and a device for calculating the coordinates of the navigation object from the found distance values placed on a support vessel.

The disadvantage of this system is the large error in determining the coordinates associated with the variability of the speed of sound in the marine environment.

Also known is a hydroacoustic synchronous rangefinder navigation system [8], containing a bottom base of M hydroacoustic transponders with different response frequencies, a transmitter located on the navigation object, the input of which is connected to the first output of the clock generator, an M-channel receiver whose outputs are connected to the inputs of the M meters the propagation time of hydroacoustic signals to the corresponding transponder and vice versa, the second inputs of which are connected to the second output of the clock generator c, M × N blocks for converting time intervals in distance according to the number N of possible ray paths, the inputs of which are connected to the corresponding outputs of measuring instruments for propagation time, M blocks for selecting the maximum value, the inputs of which are connected to the outputs of N blocks of each of the M channels for converting time intervals in distance , the coordinate calculator of the navigation object, the input of which is connected to the outputs of the M blocks for selecting the maximum value.

The presence in the structure of the navigation system of blocks for converting time intervals into distances, operating according to an algorithm that takes into account the variability of the speed of sound and the effects of multipath, reduces the error in determining the coordinates. Such a system in technical essence is the closest to the proposed invention.

The disadvantage of this navigation system is the relatively short range when operating the navigation object near the bottom and when using bottom beacons responders, which is associated with the effects of refraction of sound near the bottom. The technical solution [3] is based on the task of developing a sonar synchronous navigation system with a longer range without increasing the error in determining the coordinates of the navigation object. The problem is solved by the known device [3] is solved by the fact that the composition of the long-range hydroacoustic synchronous long-range navigation system containing a bottom navigation base of M hydroacoustic transponders with different response frequencies f _m (m = 1-M), the clock generator located on the navigation object, an acoustic transmitter with a sampling frequency f ₀ , the input of which is connected to the first output of the clock generator. M-channel receiver for receiving response signals with frequencies f _m , M measuring the propagation time of acoustic signals to a transponder operating on the frequency of this channel and vice versa, the first inputs of which are connected to the outputs M of the channel receiver, and the second inputs are connected to the second output of the clock generator , M × N blocks for converting time intervals in distance according to the number N of possible ray paths, the inputs of which are connected to the outputs of the corresponding measuring instruments for propagation time, M blocks for selecting max of the distance, the inputs of which are connected to the outputs of N blocks for converting time intervals to distances of this channel, the coordinates calculator of the navigation object, the first input of which is connected to the outputs of M blocks for selecting the maximum distance, an additional second bottom navigation base from M sonar pinger beacons with different radiation frequencies F _m (m = 1-M) mechanically associated with the corresponding M beacon transponders containing M synchronously operating clock generators, M sensors with different operating frequencies F _m , the inputs of which are connected to the outputs of the clock generators, M hydroacoustic emitters with operating frequencies F _m , the inputs of which are connected to the outputs of the transmitters with the corresponding operating frequencies.

In addition, the second synchronization generator, which works synchronously with the pinger beacon clock generators, is additionally located at the navigation object, the first output of which is used to synchronize the M synchronously working clock generators of the hydroacoustic pinger beacons before they are installed at the bottom, a towed receiving acoustic antenna, and a second M channel receiver for receiving acoustic signals of pinger beacons, the input of which is connected to the output of the towed receiving acoustic antenna, M measure the propagation time of acoustic signals from pinger beacons to the navigation object, the first inputs of which are connected to the outputs of the second M channel receiver, and the second inputs are connected to the second output of the second clock generator, additional M blocks for converting time intervals into distances, the inputs of which are connected to the outputs of M measuring the propagation time of acoustic signals from pinger beacons to the navigation object, and the outputs are connected to the second inputs of the coordinate computer of the navigation object, and M hydro-acoustic emitters of pinger beacons and a towed receiving acoustic antenna are located near the seabed at a distance of no more than a wavelength at operating frequencies F _m , and additional M blocks for converting time intervals into distances calculate the desired distances r _m through the measured propagation times t _m using the well-known formula taking into account the propagation velocity of the near-bottom wave, previously calculated through the parameters of the boundary media of the water-seabed interface according to the well-known formula minute and the velocity of sound in the bottom layer of water and the density and velocity of sound in the sedimentary seabed layer [3].

Significant disadvantages of the well-known long-range sonar synchronous long-range navigation system [3] is that obtaining the coordinates of an underwater object is burdened by numerous and time-consuming calculations due to taking into account the propagation velocity of the near-bottom wave, density and speed of sound. When conducting research in areas with complex terrain, the efficiency of calculations can lead to the opposite result, i.e. to the manifestation of an additional error in the final results of determining the coordinates of the underwater object. In addition, taking into account the fact that the bottom navigation base is located at the bottom, and the acoustic signal receiver is located on the underwater object, i.e. at different horizons in depth, then correction factors must also be entered into the calculations.

The objective of the proposed technical solution is to increase reliability in determining the coordinates of an underwater object through a sonar navigation system while reducing the complexity of determining coordinates.

The problem is solved due to the fact that in the hydroacoustic synchronous rangefinder navigation system for positioning underwater objects in the navigation field, arbitrarily placed hydroacoustic transponders containing a bottom navigation base of M hydroacoustic transponders with different response frequencies f _m (m = 1-M), placed on the navigation object, the clock generator, an acoustic transmitter with a sampling frequency f ₀ , the input of which is connected to the first output of the clock generator. M-channel receiver for receiving response signals with frequencies f _m , M meters of propagation time of acoustic signals to a transponder operating on the frequency of this channel and vice versa, the first inputs of which are connected to the outputs of the M-channel receiver, and the second inputs are connected to the second output of the generator clock pulses, M × N blocks for converting time intervals to distances in the number N of possible ray paths, the inputs of which are connected to the outputs of the corresponding propagation time meters, M blocks of maxim selection of the distance value, the inputs of which are connected to the outputs of N blocks for converting time intervals to the distance of the given channel, the coordinates calculator of the navigation object, the first input of which is connected to the outputs of M blocks for selecting the maximum distance, M hydroacoustic transponders are equipped with M hydroacoustic pinger beacons, forming an additional second bottom navigation base of M sonar pinger beacons with different radiation frequencies F _m (m = 1-M) mechanically associated with the corresponding M hydroacoustic transponder beacons containing M synchronously operating clock generators, M transmitters with different operating frequencies F _m , the inputs of which are connected to the outputs of the clock generators, M hydroacoustic emitters with working frequencies F _m , the inputs of which are connected to the outputs of the transmitters with the corresponding operating frequencies, the second synchronization generator, which works simultaneously with the generators of the hydroacoustic pinger beacons The first output of which is used to synchronize M synchronously operating clock generators of hydro-acoustic pinger beacons before installing them on the bottom, a towed receiving acoustic antenna, a second M-channel receiver for receiving acoustic signals of hydro-acoustic pinger beacons, the input of which is connected to the output of the towed receiving acoustic antenna, M meters of propagation time of acoustic signals from sonar pinger beacons to a navigation object, the first inputs of which are connected to the second M-channel receiver, and the second inputs are connected to the second output of the second clock generator, additional M blocks for converting time intervals into distances, the inputs of which are connected to the outputs of M meters of the propagation time of acoustic signals from sonar pinger beacons to the navigation object, and the outputs are connected with the second inputs of the calculator of coordinates of the navigation object, and M sonar emitters of sonar beacons-pingers and towed receiving acoustic Enna located close to the seabed at a distance not more than the wavelength at the operating frequency F _m, and an additional M block transform timeslots desired distance calculated in the distance r _m through the measured propagation times t _m, unlike the prototype [3] on the object navigation set receiver- receiving satellite signals, the first receiving antenna of which is installed on its body, and the second receiving antenna is on the block of the counter of movements of the cable, connecting the navigation object to the towed receiving aka a acoustic antenna, and n receiving antennas are installed on sonar pinger beacons, M sonar transponders are equipped with an anchor ballast with a sonar disconnector, the antenna of the M-channel receiver is made of cylindrical shape from M hydrophones, forming in the horizontal plane two navigation bases for recording acoustic signals, M hydroacoustic transponders and pinger beacons and the navigation object are equipped with sensors for measuring the speed of sound in water, hydrodynamic pressure, orientation, in numerator object navigation coordinate their inputs connected to the outputs of the maximum value selection unit distance in the M-th channel receiver-indicator of satellite radio, hydrodynamic pressure measuring sensors, sound velocity and orientation.

In the inventive sonar synchronous rangefinder navigation system for positioning underwater objects in the navigation field of arbitrarily placed sonar transponders, the common essential features for her and her prototype are:

- long-range sonar synchronous long-range navigation system containing a bottom navigation base of M hydroacoustic transponders with different response frequencies f _m (m = 1-M);

- clock generator located on the navigation object, an acoustic transmitter with a sampling frequency f ₀ , the input of which is connected to the first output of the clock generator;

- M-channel receiver for receiving response signals with frequencies f _m ;

- M meters of propagation time of acoustic signals to the transponder operating on the frequency of this channel and vice versa, the first inputs of which are connected to the outputs of the M-channel receiver, and the second inputs are connected to the second output of the clock generator;

- M × N blocks for converting time intervals into distances according to the number N of possible ray paths, the inputs of which are connected to the outputs of the respective measuring instruments for propagation time;

- M blocks for selecting the maximum distance value, the inputs of which are connected to the outputs of N blocks for converting time intervals in the distance of this channel;

- a calculator of coordinates of the navigation object, the first input of which is connected to the outputs of M blocks for selecting the maximum distance value;

- the second bottom navigation base of M hydro-acoustic pinger beacons with different radiation frequencies F _m (m = 1-M), mechanically associated with the corresponding M transponder beacons containing:

- M synchronously operating clock generators;

- M transmitters with different operating frequencies F _m , the inputs of which are connected to the outputs of the clock generators;

- M sonar emitters with operating frequencies F _m , the inputs of which are connected to the outputs of the transmitters with the corresponding operating frequencies;

- a second clock generator located at the navigation object operating synchronously with the clock generators of the pinger beacons, the first output of which is used to synchronize M synchronous clock generators of the sonar beacons before they are installed on the bottom;

- towed receiving acoustic antenna;

- a second M-channel receiver for receiving acoustic signals of pinger beacons, the input of which is connected to the output of the towed receiving acoustic antenna;

- M meters of propagation time of acoustic signals from pinger beacons to the navigation object, the first inputs of which are connected to the outputs of the second M-channel receiver, and the second inputs are connected to the second output of the second clock generator;

- additional M blocks for converting time intervals to distances, the inputs of which are connected to the outputs of the M meters of the propagation time of acoustic signals from pinger beacons to the navigation object, and the outputs are connected to the second inputs of the coordinates calculator of the navigation object;

- M hydro-acoustic emitters of pinger beacons and a towed receiving acoustic antenna are located near the seabed at a distance of not more than a wavelength at operating frequencies F _m ;

- additional M blocks for converting time intervals to distances calculate the desired distances r _m through the measured propagation times t _m . A comparative analysis of the essential features of the inventive sonar synchronous rangefinder navigation system for positioning underwater objects in the navigation field of arbitrarily placed sonar transponders and prototype shows that the first, unlike the prototype, has the following distinctive features:

- an additional second bottom navigation base of M hydro-acoustic pinger beacons with different emission frequencies F _m (m = 1-M), mechanically connected to the corresponding M transponder beacons, is also electrically connected to the same corresponding M transponder beacons;

- a receiver receiving indicator of satellite signals is installed at the navigation object, the first receiving antenna of which is installed on its body, and the second receiving antenna is on the block of movement counter of the cable, connecting the navigation object with the towed receiving acoustic antenna, and n more receiving antennas are installed on the beacons - pingers of an additional second bottom base;

- M sonar transponders are equipped with an anchor ballast with a sonar breaker;

- the antenna of the M-channel receiver is made of a cylindrical shape from M hydrophones, forming in the horizontal plane two navigation bases for recording acoustic signals;

- the coordinates calculator of the navigation object with its inputs is connected to the outputs of the unit for selecting the maximum distance in the M-th channel, the receiver-indicator of satellite radio signals, sensors for measuring hydrodynamic pressure, sound speed and orientation;

- M hydroacoustic transponders and pinger beacons, the navigation object and the towed receiving acoustic antenna are equipped with sensors for measuring the speed of sound in water, hydrodynamic pressure, orientation.

The combination of new distinctive features of the claimed object of technology provides a technical result, which consists in increasing the reliability in determining the coordinates of an underwater object using a sonar navigation system while reducing the complexity of determining coordinates due to the fact that numerous calculations of the velocity of propagation of the bottom wave, density and speed of sound in bottom layer of water, density and speed of sound in the sedimentary layer of the seabed, about Provides information redundancy in determining the coordinates of the underwater navigation object, which reduces the error in determining the coordinates of the underwater navigation object.

The essence of the proposed technical solution is illustrated by drawings.

Figure 1. The block diagram of the device.

In the drawing and in the description, the following notation:

1 _m - transponder of the m-th channel with a sonar beacon-pinger 1 _n , 2 - transmitter of acoustic request pulses at a frequency f ₀ , 3 - first M-channel receiver of acoustic response signals at frequencies f _m , 4 _m - meter of propagation time of acoustic signals to the transponder beacon and back in the m-th channel, 5 _m - block for selecting the maximum distance value in the m-th channel, 6 _mn (m = 1-M, n = 1-N) - block for converting time intervals in the distance, 7 - calculator of coordinates of the navigation object, 8 - first clock generator, 9 _m - clock generator number of mth sonar pinger beacon, 10m - transmitter of the mth sonar pinger lighthouse, 11m - emitter of the mth sonar pinger beacon, 12 - second clock generator, 13 - towed receiving acoustic antenna, 14 - second M-channel the receiver of acoustic signals of sonar sonar pinger beacons, 15 _m is a time meter of propagation of acoustic signals from the sonar beacon pinger to the navigation object, 16 _m is an additional unit for converting time intervals in distance m anala, 17 - receiver indicator of satellite radio signals, 18 - sensor for measuring the speed of sound, 19 - sensor for measuring hydrodynamic pressure, 20 - orientation sensor.

Figure 2. Underwater navigation object (figa - side view, figb - right view, figv - front view). In figure 2, the positions denote the antenna 21 of the receiver of acoustic signals 2, the emitter 22 of the transmitter of acoustic signals 2, the electronics unit 23, the unit of pre-amplifiers 24, the sensor for measuring the speed of sound 18, the sensor for determining hydrodynamic pressure 19, the orientation sensor 20, hydrophones 25, hydrodynamic stabilizers 26, cargo quotation 27, cardan 28, slope sensor 29 of the cable 30, drawbar 31, block counter 32, antenna 33 of the receiver 17 satellite signals, fairing 34, plate 35 steel, bracket 36 perforated.

Figure 3. Timing diagrams of signals "REQUEST" (figa) and "RESPONSE" (fig.3b) of bottom sonar transponders.

Figure 4. Timing diagrams of signals “REQUEST” (figa), “ANSWER” (fig.4b), “FLAT” (fig.4c) of sonar pinger beacons.

Figure 5. Functional diagram of the receiver of acoustic signals 2. The receiver of acoustic signals 2 consists of an amplifier-limiter 37, designed to amplify and normalize the signal fed to the receiver input from the antenna of the bottom transceiver, two-channel quadrature detection and filtering circuit 38, consisting of multipliers 39 and 40, low-pass filter 41 and the low-pass filter 42 of the decision circuit 43 for the availability of Fd - one channel, the low-pass filter 44, low-pass filter 45 and the circuit 46 for deciding the presence of Fd - another channel, the decoder 47 hydroacoustic signals (decoder commands) Jelya 48, a reference frequency switch 49, an 8192 Hz-50 oscillator, a frequency synthesizer 51, a response signal shaper 52, a power amplifier 53, from which the signal is transmitted through a radiating antenna 22 through the hydrosphere to the bottom sonar transponders 1 ₁ , 1 ₂ , 1 _m and sonar pinger lighthouses 1 _p .

6. Timing diagrams of the receiver of acoustic signals in the "request-response" mode.

7. The design of the sonar pinger lighthouse. The hydro-acoustic pinger lighthouse 1 _p consists of a spherical body 54, on which a radiator antenna 56, buoy 57 with zero buoyancy are installed, in which a receiver antenna indicator of the satellite navigation system, an electronics unit 58, a power supply unit 59, a ballast-armature circuit breaker 61, hydrophones 62.

The claimed technical solution is intended to determine the coordinates of underwater objects of various types and purposes relative to various types of sonar transponders (beacon transponders) in ultra-short base mode.

Such underwater objects can be autonomous and towed underwater vehicles, various underwater research devices and stations, devices and mechanisms for the exploration and production of minerals, inspection of underwater trunk pipelines and offshore economic facilities having structural elements and mechanisms located on several horizons in depth, and can be used in oceanographic and geological studies, mining mym and other types of underwater operations mainly in local areas.

The emitter 22 and hydrophones 25 form a common sonar transceiver antenna, which is designed to work as part of a sonar navigation system with an ultrashort base (HANS-UKB). The hydro-acoustic transceiver antenna is designed to emit and receive acoustic signals for subsequent determination of the position of the acoustic beacon in a certain range of ranges relative to geographical coordinates and can be performed in three versions, depending on the type of underwater vehicles. For underwater vehicles of the Mir and Sound-6 type with a range of antenna ranges of up to 8000 m, underwater vehicle of the Mezoskan-M type to 3000 m (vehicles of the Mezoskan-M type) and for underwater vehicles of the Gnome and “Type” Microsound ”up to 500 m, respectively.

The composition of the sonar transceiver antenna includes a multi-channel receiving system, a power amplifier, a microcontroller control and communication module.

The hydro-acoustic transceiver antenna provides radiation and reception of signals, the format of which corresponds to the parameters of one of the beacon-transponders such as “MO-D”, “GMO-6000”, “GMO-2000”, “GMO-200” and provides equivalent angular accuracy not worse than 0.03 ° in the long-range mode and 0.3 ° in the short-range mode.

Orientation sensor 20 is a high-precision inertial gyrocompass-type sensor for measuring slopes and heading of a sonar transceiver antenna. In a specific technical implementation, a “U-PHINS” sensor from IXSEA is used. Similar orientation sensors 20 are installed on the bottom sonar transponders, sonar pinger beacons.

The sound velocity sensor is a cyclic speed meter, which is an acoustic synchronization ring closed through water, formed by two acoustic transducers, an amplifier and a pulse generator, triggered by signals from the amplifier output (1. Gusev MN, Yakovlev GV Hydroacoustic Doppler logs // Shipbuilding abroad, 1976, No. 5, pp. 53-57. 2. Ship speed meters / A.A. Khrebtov, V. N. Koshkarev et al. - Shipbuilding, 1978, p.133).

The hydrodynamic pressure sensor 19 is a sensor, the analogue of which is the pressure sensor described in the description of patent RU No. 23228757.

Each antenna 33 of the receiver-indicator 17 of the satellite navigation system is equipped with a satellite radio channel type "Sea Tooth". For raising the antenna 33 of the satellite radio channel to the surface, for example, a Lerok type marine winch or positive buoyancy such as an emergency buoy used on submarines with tilt sensors and length of etched cable installed on them can be used.

A transceiver sonar antenna is also installed on the sonar lighthouse-pinger 1 _p , designed to convert acoustic signals into electrical ones and convert electrical signals into acoustic ones and an electronic unit.

The object coordinate calculator 7 is implemented on the basis of IBM PC / AT PC with appropriate software, as well as on the basis of a microprocessor that provides input / output of information and signal conversion from all recording and measuring devices of the hydroacoustic navigation system, such as the ATMEC family of microprocessor A8rR family.

The arrangement of hydrophones 25 (receivers) of the antenna for receiving hydroacoustic signals includes a steel plate 35, an arm 36 perforated, located in mutually perpendicular planes, on which hydrophones 25 are placed to form a central array of hydrophones 25 and mounted on a steel plate 6, and the extreme hydrophones are located along the axes X and Y on the bracket 36 perforated. On the perforated bracket 36, sensors for detecting the speed of sound 18, hydrodynamic pressure 19 and orientation 20 and emitter 22 are also installed.

The electronic unit 23 includes

- a receiving-amplifying device designed to receive and amplify “REQUEST” signals transmitted from an underwater object through a sonar communication channel;

- decoder signal "REQUEST", which decodes the signal "REQUEST" and determines the moment of arrival of the signal "REQUEST";

- “RESPONSE” signal shaper, which is designed to generate the “RESPONSE” signal after receiving the “REQUEST” signal;

- a power amplifier designed to amplify the “RESPONSE” signal to the required level for the purpose of its transmission through the hydroacoustic communication channel;

- a power amplifier designed to amplify the “FLAT” signal to the required level in order to transfer it via a hydroacoustic communication channel to a pringer lighthouse.

- a power supply unit that provides power to all electronic components of the electronics unit.

The electronics unit 23 is housed in a sturdy housing that protects it from the effects of hydrostatic pressure.

Bottom sonar transponders are installed on the highway or in the area of research by means of underwater objects, and their number is determined by the scope of the research. The proposed design of a transceiver sonar antenna allows for underwater navigation in the presence of two beacons transponders. The location coordinates of the underwater object are carried out similarly to the known methods and devices described in the descriptions of patents RU No. 2365939 (Method for navigating an underwater object) and RU No. 2371738 (Hydroacoustic navigation system). Navigation of an underwater navigation object relative to bottom sonar transponders and sonar pinger beacons can be carried out both in the long base mode (DB), ultrashort base (UKB), and in the combined DB / UKB mode. At the same time, the underwater object is equipped with hydroacoustic transceiver antennas corresponding to the operating mode, a navigation controller and mathematical software.

When navigating an underwater object at depths greater than 1 km, frequencies in the range from 8 to 15 KHz are used, while the energy range of communication with the beacon by the transponder will reach 10-14 km, and the error in determining the coordinates of the underwater object will be 7-10 m in DB mode and 0.3% of the range in the UKB mode and 0.5 degrees in the direction finding mode. With a working depth of less than one kilometer, it is advisable to use operating frequencies in the range of 25-35 kHz and work in the UHF mode. In this case, the maximum communication range will reach about 3 km.

Each signal of the transponder beacon has a special format and encoding and carries information about the geographical coordinates and its individual number. The most optimal communication range in the UKB mode with an immersion depth of up to 500 m is 1 km. Accuracy of determination of coordinates to 5 m.

The device, in terms of ensuring the positioning of an underwater object, is a sonar navigation system with a combined sonar navigation system with long and ultrashort bases, which allows you to use the direction finding mode and provide a solution to the problem of the underwater object reaching the installation point of the transponder beacon along the line of work being performed. At the same time, the sonar antenna of the transponder beacons as well as the underwater object represents two bases having a common center and consists of the same number of receivers.

At the same time, when all hydrophones receive at the same working frequency, the mode of determining the delay and direction of arrival of the response from the fixed beacon of the transponder in the ultrashort base mode is implemented, and when each of the hydrophones is tuned to its working frequency, the measurement mode of delays from two or several long beacon base transponder beacons.

The range of working depths of beacons of transponders is from 200 to 6000 m, the slant range of HANS-UKB is from 20 to 8000 m, depending on the purpose of the underwater object. The operating frequency range for a communication range of up to 500 m is 30-50 kHz, and for a communication range of up to 8000 m is 7-14 kHz.

Operating modes of beacons of transponders "REQUEST-RESPONSE".

In this mode, a request signal is received and emits a response signal. The request is made via the sonar channel, the request is addressed. The address is determined by its frequency of request.

The frequency range of the “REQUEST” signal is from 7 kHz to 10 kHz. The frequency range of the “ANSWER” signal is from 10 kHz to 14 kHz. The format of the “REQUEST” signal is a packet of two pulses, each of which is filled with its own frequency. The filling frequency of the first pulse is 8192 Hz. The frequency of the second pulse filling is in the range from 9 kHz to 10 kHz. The duration of the first pulse is 50 ms ± 1 ms, of the second 10 ms ± 0.02 ms. The repetition period is 100 ms.

The first pulse takes the beacon out of sleep mode. The second pulse records the time of arrival of the signal and determines the address of the beacon.

The “RESPONSE” signal format is a packet of two pulses, each of which is filled with its own frequency. The filling frequency of the first pulse is in the range from 10 kHz to 11.5 kHz. The frequency of the second pulse filling is in the range from 11.5 kHz to 14 kHz. The duration of the first pulse is 50 ms ± 1 ms, of the second 10 ms ± 0.02 ms. The repetition period is 100 ms.

The first pulse is used to measure direction. The second pulse is used to measure range.

The ANSWER signals are the same for each of the beacons.

The root-mean-square error of recording the time of arrival of the “REQUEST” signal via the hydroacoustic channel is 2 ms, with a noise pressure level in the zone of the beacon in the 1 Hz band at a frequency of 1 kHz - not more than 0.1 Pa.

The probability of skipping the signal "REQUEST" at a noise pressure level of 0.1 Pa in the band of 1 Hz at a frequency of 1 kHz, P _ol - 10 ^-4 , no more.

The sensitivity of the receiver is not worse than 100 dB relative to 1 μPa at a distance of 1 m.The level of acoustic pressure generated by a receiving-emitting antenna in the working frequency band should be at least 190 dB relative to 1 μPa at a distance of 1 m.The radiation pattern of a receiving-emitting antenna is unidirectional. The width of the radiation pattern at the level of 0.707 in the working frequency band is ± 45 ° ± 5 °.

Sensitivity at reception at frequencies from 7 kHz to 10 kHz - 300 μV / Pa, not less.

Sensitivity to transmission in the frequency range from 10 kHz to 13.5 kHz - 4.5 Pa / V, not less.

The parameters of the signal "REQUEST" transmitted through the hydroacoustic communication channel (figa):

a pack of two pulses filled with carrier frequencies Fd (standby) and Fi1 or Fi2 (measuring);

first pulse duration τ _id - 50 ms ± 1 ms;

the duration of the second pulse τ _ui - 10 ms ± 0.02 ms;

the repetition period of the first and second pulses Tc - 0.1 sec;

the frequency of filling the first pulse Fd - 8192 Hz;

the frequency of filling the second pulse Fi1 - 8474 Hz;

the filling frequency of the second pulse Fi2 is 8928 Hz.

The parameters of the signal "ANSWER" (figb):

- a pack of two pulses filled with carrier frequencies Fп (bearing) and Fдал (range);

first pulse duration τ _id - 50 ms ± 1 ms;

the duration of the second pulse τ _ui - 10 ms ± 0.02 ms;

the repetition period of the first and second pulses Tc - 0.1 sec;

the frequency of filling the first pulse Fpel - 10000 Hz;

the frequency of filling the second pulse Fdal - 10416 Hz.

An acoustic request is made through a power amplifier with a piezoceramic emitter 22. The response signals are received by the central array of hydrophones, they are amplified, filtered, quadrature selected, digitized and processed by the coordinate calculator 7 of the underwater object. The coordinate calculator 7 also receives information from all the hydrodynamic pressure sensors 19, the sound detection speed 18 and the orientation sensors 20. The information coming from them during each response receiving cycle is attached to the acoustic information packet. Subsequently, during the final processing of the recorded and measured data in the coordinate calculator 7, information from the receiver-indicator 33 of the GPS navigation satellite system is used, the exact geographical coordinates of the location of the underwater object are calculated.

In this case, the measured travel time is recalculated taking into account the profile of the speed of sound in an inclined range, and the direction of arrival of the wave on the surface of the antenna, taking into account the slopes and azimuth of the antenna itself, allows you to determine the point from which the sound was generated. The measurement of travel time is carried out by analyzing the shape of the received sound signal, while the accuracy of the time measurement is determined by the bandwidth of the receiving path and the signal-to-noise ratio. The direction of arrival of the sound wave is determined by measuring the phase difference of the signals received by different hydrophones, followed by the conversion of the phase difference into geometric angles, taking into account the characteristic wavelength of the acoustic signal and the spatial separation of the receivers. The accuracy of the direction measurement is determined by the distance between the receivers and the signal-to-noise ratio. The accuracy of measuring the travel time, or, in other words, the accuracy of determining the position of an object along a beam, does not depend on distance (at a sufficiently high signal level compared to noise) and for traditional long-range systems is a fraction of a meter. With a fixed angular resolution, the error in measuring the position of the object across the beam increases linearly with distance and, as a rule, is characterized as a percentage of the slant range.

The antennas 17 of the receiver-indicator 33 of the GPS navigation satellite system are placed on the counter unit 32 of the cable-cable 29, equipped with a slope sensor 29 and connected to the towed receiving acoustic antenna 14. A similar connection design is also used when the underwater navigation object is a towed underwater vehicle and is coupled to towing vessel.

The part of the cable-cable 29, which is attached to the underwater object, is located in the drawbar 3 and together with the cardan 28 serves as fastening elements. Cargo quotation 27, fairing 34 and hydrodynamic stabilizers are designed to ensure seaworthiness of the underwater navigation facility.

The antennas 17 of the receiver-indicator 33 of the GPS navigation satellite system are also placed on the sonar pinger 1 _p , which can be moved to a different depth horizon or in the surface water layer by disengaging the ballast anchor attached to its body by means of slings and an electrochemical disconnector by the command “PLAYBACK” ".

The number of installed sonar pinger beacons is determined by the tasks and scope of research. The minimum number of beacons installed in the GANS-UKB coverage area, relative to which control measurements are made, is 2.

Modes of operation of the sonar beacon-pinger 1 _p :

- "REQUEST" - "ANSWER", in this mode the sonar pinger receives a request signal and emits a response signal.

- “SPLIT”, in this mode, the sonar pinger receives an ascent command and sends a signal to the electrochemical disconnector and the disconnecting mechanism, made in the form of slings with a drive and separating the ballast anchor.

The sonar pinger beacon request is addressed. The address is determined by its frequency of request.

The frequency range of the “REQUEST” signal and the “PLAY” command is from 7 kHz to 10 kHz. The frequency range of the “ANSWER” signal is from 10 kHz to 14 kHz. The format of the “REQUEST” signal is a packet of two pulses, each of which is filled with its own frequency. The filling frequency of the first pulse is 8192 Hz. The frequency of the second pulse filling is in the range from 9 kHz to 10 kHz. The duration of the first pulse is 50 ms ± 1 ms, of the second 10 ms ± 0.02 ms. The repetition period is 100 ms.

The first impulse removes the sonar pinger from the "sleep" mode. The second pulse records the time of arrival of the signal and determines the address of the sonar beacon-pinger. The format of the signal “EXPLORE” is a packet of three pulses, each of which is filled with its own frequency. The filling frequency of the first pulse is 8192 Hz. The filling frequencies of the second and third pulses are in the range from 7 kHz to 10 kHz.

The duration of the first pulse is 50 ms ± 1 ms, the second 50 ms ± 1 ms, and the third 50 ms ± 1 ms. The period between the first and second 300 ms, between the second and third pulses 200 ms. The first pulse removes the MO-D from the "sleep" mode.

The “RESPONSE” signal format is a packet of two pulses, each of which is filled with its own frequency. The filling frequency of the first pulse is in the range from 10 kHz to 11.5 kHz. The frequency of the second pulse filling is in the range from 11.5 kHz to 14 kHz. The duration of the first pulse is 50 ms ± 1 ms, of the second 10 ms ± 0.02 ms. The repetition period is 100 ms.

The first pulse is used to measure direction. The second pulse is used to measure range.

The “RESPONSE” signals are the same for each of the sonar pinger beacons.

The root-mean-square error of recording the time of arrival of the “REQUEST” signal is 1 ms, at the noise pressure level in the zone of location of the pinger beacon in the 1 Hz band at a frequency of 1 kHz, not more than 0.1 Pa.

The probability of skipping the signal "REQUEST" at a noise pressure level of 0.1 Pa in the band of 1 Hz at a frequency of 1 kHz, P _ol - 10 ^-4 , no more.

The probability of error when receiving the “EXPLORE” command with additive interference and a signal-to-noise ratio equal to 10, no more than Р _Ош - 0.5-10 ^-6 .

The sensitivity of the receiver is not worse than 100 dB with respect to 1 μPa at a distance of 1 m.

The level of acoustic pressure created by the receiving-emitting antenna in the working frequency band should be at least 190 dB with respect to 1 μPa at a distance of 1 m.

The radiation pattern of the receiving-emitting antenna is the upper hemisphere.

Sensitivity at reception at frequencies from 7 kHz to 10 kHz - 200 μV / Pa, not less.

Sensitivity to transmission in the frequency range from 10 kHz to 13.5 kHz - 4.5 Pa / V not less.

The autonomy of the sonar pinger lighthouse in "sleep" mode is 12 months, no less.

Number of answers - 100,000, no less.

Power source - alkaline elements of type LR20, voltage 27 V, capacity 16 Ah, not less.

The anchor-ballast disconnector is electrochemical, while the type of drive is electromagnetic; solenoid winding resistance - 4 Ohms; minimum tripping current - 2.5 A; control - impulse; minimum pulse duration at minimum current - 500 ms.

Structurally, the sonar lighthouse-pinger is made in the form of a sphere of aluminum alloy with a diameter of 350 mm, ensuring operation at depths up to 6000 m.

Positive buoyancy of at least 4 kg. Operating temperature range - from 0 ° to + 40 ° С.

The purpose of the operating modes of the sonar beacon-pinger and signal parameters corresponding to them.

REQUEST-RESPONSE mode. In this mode, one of the two sonar pinger beacons receives the addressed sonar signal “REQUEST”, transmitted from an underwater navigation facility or from a supporting vessel. The address of the sonar beacon-pinger is determined by the frequency of filling of the second pulse. Then the pringer beacon, to which the “REQUEST” signal was transmitted, sends a “RESPONSE” signal. Response frequencies are the same for each of the two sonar pinger beacons.

Parameters of signals "REQUEST":

a pack of two pulses filled with carrier frequencies Fd (standby) and Fi1 or Fi2 (measuring);

first pulse duration τ _id - 50 ms ± 1 ms;

the duration of the second pulse τ _ui - 10 ms ± 0.02 ms;

the repetition period of the first and second pulses Tc - 0.1 sec;

the frequency of filling the first pulse Fd - 8192 Hz;

the frequency of filling the second pulse Fi1 - 7462 Hz;

the frequency of filling the second pulse Fi2 - 8064 Hz.

The timing diagram of the command is presented in figa.

RESPONSE signal parameters:

- a pack of two pulses filled with carrier frequencies Fpel (bearing) and Fdal (range);

first pulse duration τ _id - 50 ms ± 1 ms;

the duration of the second pulse τ _ui - 10 ms ± 0.02 ms;

the repetition period of the first and second pulses Tc - 0.1 sec;

the frequency of filling the first pulse Fpel - 10000 Hz;

the frequency of filling the second pulse Fdal - 10416 Hz.

The timing diagram of the command is presented in figb. The command "EXPLORE". This command is used to move the sonar pinger from the bottom to another depth horizon from the bottom of the reservoir.

Before the start of the command, the impulse Fd is transmitted, similar to the “REQUEST” signal. Then, after 0.3 seconds, a command follows, which is a pack of two pulses, each of which is filled with its carrier frequency. The filling frequency of the first pulse is F1 and is the same for all sonar pinger beacons, and the second F2 varies in the range from 7 kHz to 9 kHz. The period between pulses is 0.2 seconds. The timing diagram of the command is presented in figv. Filling frequency Fd = 8192 Hz. The filling frequency F1 = 8333 Hz. The frequency of filling F2 varies and is 7462 Hz and 8064 Hz. It consists of the following main nodes:

an amplifier-limiter designed to amplify and normalize the signal supplied to the input of the receiver from the GMO-6000 and GMO-2000 antennas;

a two-channel quadrature detection and filtering scheme, consisting of the multipliers P1 and P2, the low-pass filter, the low-pass filter and the decision-making scheme for the presence of Fd - one channel, the low-pass filter, 3 low-pass filter and the decision circuit for the presence of F and another channel;

- a decoder of hydroacoustic signals (decoder of commands);

phase shifter;

reference frequency switch;

generator 8192 Hz;

frequency synthesizer;

signal shaper "response";

power amplifier.

The receiver GMO-6000 and GMO-2000 is made according to the scheme of the optimal quadrature detector of a radio pulse with a random phase, which allows you to maximize the signal-to-noise ratio and thereby improve the reception quality, increasing the accuracy of range measurement.

In the absence of a useful signal, the receiver is in standby mode. The inputs of the multipliers P1 and P2 from the phase shifter receive continuous reference voltages Uoop with a frequency Fo equal to the filling frequency of the first pulse of the “REQUEST” signal Fd = 8192 Hz, 90 ° shifted in phase relative to each other. At this time, only low-pass filter 1 and low-pass filter 2 are included for receiving a duty pulse Fd. The passband of these low-pass filters corresponds to a pulse duration of 50 ms. The current consumption in this mode is minimal and is not more than 500 μA.

The decision circuit on the presence of the signal Fd constantly analyzes the output voltages of the low-pass filter and low-pass filter [Us (t) and Uc (t), respectively, according to a given algorithm). If, after the arrival of the first pulse (duty) with a frequency Fd, the voltages Us (t) and Uc (t) satisfy the specified decision criterion, the circuit will notify the decoder of the commands by applying a pulse to its input, the front of which corresponds to the moment the useful signal appears on GMO-6000 and GMO-2000 receiver input. The decoder, having detected the appearance of this pulse, “wakes up” the microcontroller and gives the command to the reference frequency switching circuit to turn off Uoop and turn on low-pass filter 3 and low-pass filter 4 to receive the pulse F and. The bandwidth of these filters corresponds to a pulse of 10 ms for GMO-6000 and 5 ms for GMO-2000. At the inputs of the multipliers P1 and P2 at this time a voltage of 0 is supplied, and reception is not performed. 0.075 seconds after receiving the first pulse, the decoder gives permission to the reference frequency switching circuit to turn on the reference voltages Uo with a frequency equal to the frequency of filling the second pulse of the “REQUEST” signal Fi1 or Fi2. Then the receiver awaits its arrival. If after 0.1 seconds the second F1 or F2 was received from the beginning of the first pulse, then 20 ms after receiving it, the decoder turns off Uoop and instructs the “RESPONSE” signal conditioner to generate and transmit a response signal to the vessel. After that, the receiver is turned off for 8 seconds and no signals are received. After this time, the decoder puts the receiver in standby mode. Timing diagrams to more clearly represent the various modes of operation of the GMO-6000 and GMO-2000 are shown in figure 4.

The block diagram of the electronic part of the MO is presented in figure 5.

It consists of the following main nodes:

an amplifier-limiter designed to amplify and normalize the signal received at the input of the receiver from the MO-D antenna;

a two-channel quadrature detection and filtering scheme, consisting of the multipliers P1 and P2, the low-pass filter, the low-pass filter and the decision-making scheme for the presence of Fd, F1 and F2 - one channel, the low-pass filter 3, low-pass filter and the decision circuit for the presence of F - another channel;

- a decoder of hydroacoustic signals (decoder of commands);

phase shifter;

reference frequency switch;

generator 8192 Hz;

frequency synthesizer;

signal shaper "response";

power amplifier.

Hydroacoustic synchronous rangefinder navigation system for positioning underwater objects in the navigation field of arbitrarily placed sonar transponders works as follows.

Located on the navigation object, the first clock generator 8 starts the acoustic pulse transmitter 2 at the request frequency f ₀ and resets the counters M of the meters 4 _{m of} the propagation time of the acoustic signals to the transponder and back in each channel. Acoustic signals propagating in the aquatic environment are received by 1 _m transponders, re-emitted and received by the first M-channel receiver 3 acoustic response signals at operating frequencies f _m 3. The receiver-amplified 3 signals from the output of each channel go to the blocking input of each of the meters 4 _m propagation time and lock its front edge pulse integrator-timestamp clock generator 8, and information on the number of accumulated time stamp is transmitted in digital form from each integral torus in the respective blocks 6 _mn transformation distance in time slots N for each m-th channel. Different blocks of 6 _mn transformations of the same m-th channel differ in the values of the coefficients characterizing the type of ray path in the algorithm for converting the propagation time into an inclined distance. The values of the inclined distances found in blocks 6 _mn go to the inputs of blocks 5 _{m to} select the maximum distance values, and the maximum values of distances from the outputs of blocks 5 _m go to the first input of the calculator 7 coordinates of the navigation object. According to a similar scheme and well-known methods [1], the coordinates of transponders and mechanically associated sonar pinger beacons are determined by the known coordinates of the navigation object in the calibration mode of the navigation base. If the navigation object is within the range of the first subsystem, then its coordinates are determined by the first subsystem.

At the same time, synchronously operating clock generators of 9 _m sonar pinger beacons launch transmitters of 10 _m sonar pinger beacons, which in turn feed excitation pulses to sonar emitters 11 _m sonar pinger, and the second clock generator 12 located on the navigation object resets the counters of the pulse-time stamp meters 15 _m propagation time of acoustic signals from sonar pinger beacons to the navigation object. Acoustic signals emitted by sonar beacons pingers with operating frequencies F _m propagate in the aquatic environment and are received by the towed receiving acoustic antenna 13 located at the navigation object, from the output of which they are fed to the input of the second M-channel receiver 14. Acoustic signals amplified by receiver 14 are fed to the blocking the input of the corresponding meters is 15 _{m of} the propagation time of acoustic signals from sonar pinger beacons to the navigation object, and information about the time The digital signal is transmitted to additional blocks 16 _{m of} conversion of time intervals in the distance. The distances calculated in blocks 16 _m go to the calculator 7 coordinates of the navigation object.

Information on the acoustic parameters of the boundary media of the water-seabed interface is continuously recorded and entered into additional blocks 16 _{m of} conversion of time intervals into distances. Information about the geographical coordinates of the responder beacons and the associated sonar pinger beacons obtained during the calibration of the navigation system, as well as obtained via the satellite channel, is entered into the coordinate calculator of the navigation object.

To increase the reliability of determining the coordinates of an underwater object, there are two methods for increasing the accuracy of sonar systems. This is an increase in the spatial diversity of the receivers and an increase in the signal-to-noise ratio.

The study of structural and functional schemes of known systems showed that almost all known technical solutions use receiving antennas of relatively small sizes - less than half a meter. At the same time, an increase in the separation of hydrophones to 1-1.5 m will proportionally increase the angular accuracy of the transceiver sonar antenna with a fixed signal to noise ratio.

An increase in the signal-to-noise ratio is achieved by increasing the signal power and reducing the noise level. As a rule, in the sources of the analyzed sound signals for receiving antennas, piezoceramic emitting elements operating at the limit of radiated power are used, therefore, the only way to amplify the signal is to increase its energy by increasing the duration. An increase in the duration in the tonal mode leads to a decrease in the accuracy of measuring the travel time of an acoustic wave and, thereby, to a deterioration of the overall navigation performance. The only real way to increase the signal energy without compromising the resolution of the system in range is to use complex signals. However, the use of complex signals requires, on the one hand, a significant increase in processor performance in transponders and on-board systems, and, on the other hand, reduces the lifetime of acoustic transponders in stand-alone mode with a fixed resource of power sources.

There are a number of ways to reduce the level of acoustic noise at the receiver. The ambient noise at the receiving point has complex frequency and spatial spectra, and its effective level can be reduced by limiting the sensitivity of the receivers in areas that do not contain useful information. The limitation of sensitivity in the frequency domain is achieved by optimal filtering of signals, the limitation of sensitivity in the spatial region by passive or active beamforming. Passive formation is achieved by the use of reflective and damping elements in the antenna structure, which attenuate sound waves from undesirable directions. This method is used in most known UKB systems and is very effective and relatively cheap, but it does not allow to narrow the spatial spectrum of the analyzed signal and to achieve the lowest possible noise level. Active directivity is achieved by using multi-element phased arrays and is used, for example, in Kongsberg's HIPAP-500 system. This method of generating a reception diagram gives the best results, however, implementing antennas of this type is a very difficult and expensive task. In the proposed technical solution, an increase in the navigation accuracy of the underwater object is achieved due to the spatial separation of hydrophones to the maximum technically permissible distance with the formation of a radiation pattern that is close to uniform in the active half-space.

The practical implementation of the proposed technical solution is based on the theoretical principle of constructing the proposed sonar system for underwater navigation with an ultra-short base.

Thus, both subsystems, working independently with frequency separation, provide the determination of the coordinates of the navigation object at small and large distances with minimal error.

Information sources

1. Patent RU No. 2084924.

2. Patent RU No. 2084923.

3. Patent RU No. 2289149.

4. Patent RU No. 34020 U1.

5. Patent RU No. 2158431.

6. Patent RU No. 2308454.

7. Patent RU No. 203 8127.

8. Copyright certificate SU No. 713278.

9. Patent RU No. 2365939.

10. Patent RU No. 2371738.

11. Patent WO No. 0123908 A1, 04/05/2001.

12. Milne P.H. Hydroacoustic positioning systems. - L .: Shipbuilding, 1989, p. 49-60.

Claims (1)

Hydroacoustic synchronous rangefinder navigation system for positioning underwater objects in the navigation field of arbitrarily placed hydroacoustic transponders, containing a bottom navigation base of M hydroacoustic transponders with different response frequencies f _m (m = 1-M), a clock generator, an acoustic transmitter with a frequency located on the navigation object poll f ₀ having an input coupled to the first output clock generator, an M-channel receiver for receiving response signals h otami f _m, M gauges propagation time of the acoustic signals to the transponder, operating on this channel frequency, and conversely, the first inputs of which are connected to the outputs of the M channel receiver, and second inputs connected to the second output of oscillator clock, M × N time slots conversion units in distance in the number N of possible ray paths, the inputs of which are connected to the outputs of the respective measuring instruments of propagation time, M blocks for selecting the maximum distance value, the inputs of which are connected to by the moves of N blocks for converting time intervals in the distance of a given channel, a coordinate calculator of the navigation object, the first input of which is connected to the outputs of M blocks for selecting the maximum distance, M sonar transponders are equipped with M sonar pinger beacons, forming an additional second bottom navigation base of M sonar beacons pingers with different radiation frequencies F _m (m = 1-M), mechanically connected to the corresponding M sonar transponders containing M synchronously operating clock generators, M transmitters with different operating frequencies F _m , the inputs of which are connected to the outputs of the clock generators, M hydroacoustic emitters with operating frequencies F _m , the inputs of which are connected to the outputs of the transmitters with corresponding operating frequencies, a second clock generator is additionally placed on the navigation object operating synchronously with the generators of the sync pulses of sonar pinger beacons, the first output of which is used to synchronize M si synchronously operating generators of synchronized pulses of hydro-acoustic pinger beacons before their installation on the bottom, a towed receiving acoustic antenna, a second M channel receiver for receiving acoustic signals of hydro-acoustic pinger beacons, the input of which is connected to the output of the towed receiving acoustic antenna, M meters of propagation time of acoustic signals from hydro-acoustic pinger beacons to the navigation object, the first inputs of which are connected to the outputs of the second M channel receiver, and the second inputs with are additional to the second output of the second clock generator, additional M blocks for converting time intervals to distances, the inputs of which are connected to the outputs of the M meters of the propagation time of acoustic signals from sonar pinger beacons to the navigation object, and the outputs are connected to the second inputs of the coordinate computer of the navigation object sonar emitters sonar pinger beacons and towed receiving acoustic antenna are located near the seabed at a distance not longer wavelengths at operating frequencies F _m , and additional M time interval conversion units for distances calculate the required distances r _m through the measured propagation times t _m , characterized in that a satellite receiver receiving indicator is installed at the navigation object, the first receiving antenna of which is installed on its the casing, and the second receiving antenna is located on the displacement counter of the cable cable connecting the navigation object with the towed receiving acoustic antenna, and another n receiving antennas are mounted on idro-acoustic pinger beacons, M hydroacoustic transponders are equipped with a ballast anchor with a hydroacoustic disconnector, the antenna of the M-channel receiver is made of cylindrical shape from M hydrophones, forming two navigation bases for recording acoustic signals in the horizontal plane, M hydroacoustic transponders and pinger beacons and the navigation object are equipped sensors for measuring the speed of sound in water, hydrodynamic pressure, orientation, the coordinates calculator of the navigation object with its inputs inen with the outputs of the unit for selecting the maximum distance in the M-th channel, the receiver-indicator of satellite radio signals, sensors for measuring hydrodynamic pressure, sound speed and orientation.

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