RU2654366C1 - Active sonar - Google Patents

Abstract

FIELD: acoustics.

SUBSTANCE: invention relates to the field of hydro acoustics and can be used in the construction of systems designed to the targets detecting by the sonar method in the marine environment and their parameters measurement. To ensure the claimed technical result, an active sonar is proposed, comprising the emitting and receiving acoustic antennas, a generator device, transmission/reception switch, directivity characteristic generation unit, echo signal delay time T measurement unit from the target relative to the sounding signal emission time, sound speed vertical cut-off measuring unit, own speed measuring unit, a horizontal angle arrival angle measuring unit, the own speed radial component determining unit, unit for the distance determining traveled by the sonar during the signal to the object and back propagation, time between the second signal emission and the time at which the second echo is received measuring unit, convergence or divergence speed detection unit, radial target speed determination unit, unit of the distance detection traversed by the sonar during the time from the moment of reflection to the time of reception, distance to the target detection unit at the time of the second echo signal receiving.

EFFECT: technical result of using is in increase of the distance to the detected target measuring reliability by taking into account of the target and the sonar carrier mutual convergence/divergence speed influence.

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Description

The invention relates to the field of hydroacoustics and can be used to build systems for detecting the echo signal from objects during sonar operation and, in particular, to increase the reliability of distance measurement.

The main purpose of sonar is the remote detection of objects in the aquatic environment and measuring the distance, speed and spatial position of objects. In foreign and domestic literature (J. Warren Horton. "The basics of sonar." Sudpromgiz, 1961; AN Yakovlev, GP Kablov. "Short-range sonar." Shipbuilding, 1983, etc.) are considered structures of sonars designed to detect objects by the reflected echo signal, and the main blocks providing the solution of the tasks. Consideration of issues of automatic detection and measurement of parameters and their errors is practically not considered anywhere.

Known patent No. 2225991 for a navigation hydroacoustic station for lighting near situations containing an antenna system, a generator device, a preliminary processing path, CVS-1, CVS-2, a path for measuring the speed of sound, a listening path. The description discusses the task of measuring the distance, speed and spatial position of the detected object. Object detection is performed by the operator and the structure of distance meters, speeds are not presented.

A known system of active sonar sonar station (HAS) according to the patent No. 2393503, comprising emitting and receiving acoustic antennas, a serially connected device for generating a sounding signal, a device for generating directivity characteristics in radiation, a generating device, a serially connected device for generating directivity characteristics of a sonar system (GL) in receiving and device for processing echoes from the target, also containing a device for measuring the distance to the target, device your measurements of the radial component of the target’s speed, a serially connected device for forming the directivity characteristics of a noise-detecting system (PS), a signal processing device for a SS system, a device for measuring bearings on a target of a SS system and a unit for determining the magnitude of the bearing change (VIP), also containing a series of connected total tangential speed component and a unit for determining the tangential component of the target speed, also containing a unit for determining the speed of the target, a unit for determining Jelenia course objectives and block communication with the ship's sonar systems.

The disadvantage of this system is that it does not measure the speed of sound in the area of work, the value of which determines the very estimate of the distance.

. Этот патент является наиболее близким аналогом, который может быть взят в качестве прототипа.Known active sonar according to patent No. 2346295, containing emitting and receiving acoustic antennas, a generating device, a synchronization device, a device for generating directivity characteristics, a unit for measuring T of the delay time of an echo signal from a target relative to the moment of emission of a sounding signal, a unit for measuring the angle of arrival of an echo signal in a vertical plane, block a vertical section of the speed of sound and a unit for measuring the depth of the target, a calculator that determines the predicted times of the delay of the echo signal t _i relative to m the radiation moment of the probe signal for a set of possible target depths H _i , and a difference block defining

. This patent is the closest analogue that can be taken as a prototype.

The disadvantage of the considered technical solution is that when the probe signal propagates and the echo signal spreads over long distances, an error occurs in determining the current distance estimate, which is determined by the joint movement of the sonar and the object during the propagation of the probe signal and the echo signal.

After the probe signal is emitted, the sonar continues to move in the selected direction. For example, when the sonar speed is 6 knots, which is 3 m / s and the propagation time to the object and back is 20 s, the distance to the object, measured at the time of receiving the echo signal, will decrease by 60 m. The same thing happens when the object moves after reflection of the echo signal. The object continues to move in the same direction and during the propagation of the echo signal from the object to the sonar, equal to about 10 s, and at a speed of 3 m / s, a distance of 30 m will pass. Thus, the measured distance will differ from the actual distance at the time of the arrival of the echo signal by 90 m. This error depends on the distance and speed of the sonar and the speed of the object and varies depending on the specific situation.

The objective of the invention is to increase the reliability of determining the distance measured by a moving sonar, for a minimum time over several cycles of radiation-reception.

The technical result from the use of the invention is to increase the accuracy of measuring the distance by eliminating the error associated with the joint movement of the sonar and the object during the propagation of the signal and the echo signal, and determining the current distance taking into account the movement of the sonar and the object.

The specified technical result is achieved in that an active sonar containing a receiving antenna, a transmitting antenna, a receive-transmit switch, a generator, a control and display unit, an echo signal receiving and processing unit with a directivity characteristics forming device (UHHF), a delay time measuring unit, a unit determining the distance D, the unit for determining the radial velocity of the target, the unit for determining the speed of sound, new features have been introduced, namely, the unit for measuring the intrinsic speed V _sob , the unit for determining the course angle la targets KU, unit for determining the speed of rapprochement, unit for determining the error of distance due to its own movement D _sb , unit for determining the error of distance due to movement of the target D of the _target , unit for determining the current distance D _tech , and the receiving antenna is connected in series with the first input of the switch, with the first the input of the block of reception and processing of the echo signal with UFHN, with the unit for measuring the delay time, with the first input of the distance determination unit, with the first input of the error detection unit D _SOB , with the first input of the detection unit D _tech , the first input control and display unit, to the generator with the second input of the switch and the antenna radiation own speed measurement unit V _GSS is connected in series with the first input of the determining closing speed, with the second input of the error determination D _GSS, a second output for receiving and processing unit echoes with UFHN is connected to the measuring unit KU, the output of which is connected to the second input of the unit for determining the speed of approach, the unit for determining the speed of sound is connected to the second input of the unit for determining the distance D, the second Exit which is connected in series with the unit determining the radial velocity of the target, the block error determination D _goals and second input detection unit D _tech, the second output detection unit radial velocity is coupled to the second input of the control unit and displaying the two-way communication, and a third output for receiving and processing unit of the echo signal with UFHN is connected by two-way communication with the third input of the control and display unit.

The essence of the invention is illustrated in FIG. 1, which shows a block diagram of a system for automatic classification of short-range sonar.

1. Reception antenna

2. The antenna is radiating,

3. The receive-transmit switch,

4. The block of reception and processing of an echo signal with UFHN,

5. The delay time measurement unit,

6. The unit for determining the distance

7. The unit for determining errors due to its own motion D _sob ,

8. The unit determining the distance, taking into account its own movement and the movement of the target D _tech

9. The control and display unit,

10. Generator

11. The unit of measurement of its own speed V _sob ,

12. The unit for determining the speed of approach, taking into account the target KU relative to V _sob ,

13. The block measuring the course angle of the detected target KU,

14. The unit for determining the speed of sound,

15. The unit for determining the radial velocity of the target V _goals ,

16. The unit for determining the error in estimating the distance to the target D of the _target .

The receiving antenna 1, the receiving-transmitting switch 3, block 4, block 5, block 6, block 7, block 8, block 9 are connected in series. The output of the generator 10 is connected to the second input of the transmit-receive switch 3, the output of which is connected to the radiating antenna 2. The second input of block 6 is connected to the output of block 14, and the output of block 6 is connected to the first input of block 15. The output of block 15 is connected to series-connected blocks 16 and 8. Block 15 is connected by two-way communication to block 9, the third input of which is connected to the second output of block 4. The first and second inputs of block 12 are connected to the output of block 11 and the output of block 13, respectively, and the output of block 12 is connected to the second input of block 7 .

Blocks 1-5, 10, 13 are known devices that are used in the prototype and are described in sufficient detail in the literature on hydroacoustics (AS Kolchedantsev. “Hydroacoustic stations.” L., Shipbuilding, 1982; “Reference on hydroacoustic” . L., Shipbuilding, 1988).

Block 11 determining the speed of movement is a known device that is used on all modern ships to measure its own speed (A.V. Bogorodsky, DB Ostrovsky. "Hydroacoustic navigation and search and survey means. St. Petersburg, Publishing House LETI, 2009, p. 48).

Block 14 for determining the speed of sound is a well-known device that is produced commercially (V. A. Komlyakov. “Shipborne means of measuring the speed of sound and modeling acoustic fields in the ocean.” St. Petersburg, “Science”, 2003, pp. 50-87) .

Blocks 7, 8, 12, 15, 16 can be implemented using digital processing based on the Matlab extension packages, which provide a consistent procedure for calculating the given algorithms, are considered in the manual: A. B. Sergienko. "Digital signal processing". St. Petersburg, 2011, p. 655.

Currently, all processing of hydroacoustic signals, including the formation of directivity characteristics, basic algorithms for processing echo signals based on spectral and correlation analysis when working in real time using hardware solutions and strict computation logic, are performed on special processors (Yu.A. Koryakin, S.A. Smirnov, G.V. Yakovlev. Shipborne sonar equipment. S.-P., Nauka, 2004, pp. 278-297). A similar implementation is made in one of the analogues on CVS-1 and CVS-2 according to patent No. 2225991.

Issues related to digital signal processing, as well as the use of Matlab extension packages, which provide a consistent procedure for processing the algorithms used, are discussed in the manual: A. B. Sergienko. "Digital signal processing". St. Petersburg, 2011, p. 655.

Digital processors are well-known devices that are designed to implement specific processing algorithms using hardware solutions and strict computational logic. Their use increases the speed of digital computing systems several times and in most cases reduces hardware costs. Descriptions of special processors are given in the book: Koryakin Yu.A. Smirnov S.A. Yakovlev G.V. "Ship sonar equipment." St. Petersburg, Publishing House Science, 2004, p. 281. There is also a description of sonar systems built on the basis of special processors (p. 296., p. 328). Using the same processors, newly introduced blocks of the present invention can be implemented.

The work of the active sonar is as follows.

From the control and display unit 9, the control signals are supplied to a generator 10, which generates a probing signal, and through the switch 3, the antenna 2 radiates it into the aquatic environment. The echo signals reflected from the target are received by antenna 1 and transmitted through switch 3 to block 4. In block 4, the directivity characteristics are generated in the reception and the received echo signals are processed by standard known procedures with the choice of detection thresholds, the choice of maximums and directivity characteristics in which echo signals are detected. These are well-known procedures that are implemented in all sonars and in the prototype. All information about interference and signals is fed to the display unit 9 and presented to the operator on the indicator. This communication is two-way, through which the radiation time from block 9 and the time between emissions are transmitted to block 4. The same radiation time is used in block 5 to measure the delay time between the emitted signal and the received echo signal, which exceeded the threshold. The amount of delay determines the distance to the target in block 6, for which an estimate of the speed of sound is received from block 14 for determining the speed of sound. These standard procedures are implemented in the prototype. The measured distance estimate with the measured delay times are transmitted to the error determination unit 7. The second input of block 7 from block 12 receives an estimate of the convergence rate. The spatial position of the target may not coincide with the direction of movement, therefore, the component of the speed of movement will depend on the course angle of the target, which is determined in block 4 by the number of directional characteristics in which the echo signal from the target was detected. In block 7, a distance estimation error is determined, which is associated with a reduction in the distance when the sonar moves during the propagation of the probe signal and the reflected echo signal. In block 8, the measured distance D is reduced by the product of the approach speed and the propagation time. This distance estimate is transmitted to block 9 for display. The second output of block 6 is connected to the block 15 for determining the radial velocity of the target, which is made on two premises. After the second probe signal is emitted, the time between the emissions comes from block 9 to block 15. The distance measured by subsequent transmissions is transmitted to block 15, where the radial velocity is determined. The target may be approaching and moving away, which entails a change in sign and, accordingly, an increase or decrease in the distance during the time between sendings, which is performed in block 16 for determining the _target’s error D, which are caused by moving the target during the propagation of the echo signal from the target to the sonar. The distance received from the first package takes into account only the sonar’s own movement, and the distance received from the second package takes into account not only its own movement, but also the change in distance due to the movement of the target. The sounding signals are produced, as a rule, through a fixed time interval, which is determined by the selected scale of operation, characteristic for this sonar. For each emitted signal, the target is detected and the distance to it is measured. Distance adjustment due to the movement of the sonar is made for each package. Correction of the distance by moving the target is possible only after measuring the radial speed of the target, which is made by changing the distances measured by two consecutive premises. These distances are sequentially supplied to the radial velocity measuring unit 15.

Thus, an estimate of the distance is formed, which takes into account the influence of own movement on the estimate of the distance and the influence of the target’s speed on the estimate of the distance, which is presented simultaneously with the estimate of the radial speed of the target and the estimate of the target angle of the target.

Claims (1)

An active sonar containing a receiving antenna, a transmitting antenna, a receive-transmit switch, a generator, a control and display unit, an echo signal receiving and processing unit with a directivity characteristics forming unit (UVCN), a delay time measurement unit, a distance determination unit D, a radial velocity determination unit targets the sound velocity detection unit, characterized in that the introduced own speed measurement unit V _GSS, azimuth determination unit purpose CG determination unit convergence speed determined block distance error ELENITE due to its own motion D _GSS determining unit error distance due to the movement target A _target and a unit to determine the current distance D _tech, wherein the receiving antenna is connected in series to the first input switch, to the first input unit receiving and processing the echo signal with UFHN with delay time measurement unit, with the first input of the distance determination unit, with the first input of the error determination unit D _sv , with the first input of the D _tech determination unit, the first input of the control and display unit, with a generator in torym input switch and the antenna radiation own speed measurement unit V _GSS is connected in series with the first input of the determining closing speed, with the second input of the error determination D _GSS, the second output receiving unit and processing of echo signals from UFHN connected to the measuring unit KU, the output of which connected to the second input of the approach speed determination unit, the sound speed determination unit is connected to the second input of the distance determination unit D, the second output of which is connected in series with the determination unit Nia radial velocity of the target, the block error determination D _goals and second input detection unit D _tech, the second output detection unit radial velocity is coupled to the second input of the control unit and displaying the two-way communication, and a third output for receiving and processing unit of the echo signal with UFHN connected to two-way communication with the third the input of the control and display unit.

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