JP2023101250A - Sonar device, method, and program - Google Patents

Abstract

To acquire normal sonar output by suppressing influence of a structure or the like other than a transducer.SOLUTION: A sonar device includes: a transducer array in which a plurality of transducers having sensitivity over an entire circumference are arranged in an annular shape, a single directivity generation processing unit that individually performs, for each transducer, single directivity generation processing capable of directing a null in an arbitrary direction with respect to a reception signal in each transducer of the transducer array; and a reception processor including a phasing processing unit that performs phasing processing on the signal individually subjected to the single directivity generation processing.SELECTED DRAWING: Figure 1

Description

The present invention relates to sonar devices, methods and programs.

Sonars for small ships and drones need to be mounted in smaller sonar domes than sonars for large ships.

On the other hand, these sonars for small warships and drones are often required to support multiple missions (missions/missions, roles). Therefore, a plurality of types of sonars may be mounted in one sonar dome. In such a sonar, normal sonar output may not be obtained due to the influence of sonar structures other than the sonar itself.

JP-A-10-221434 Japanese Patent Application Laid-Open No. 2018-189602

As described above, when multiple types of sonar are mounted in one sonar dome, for example, in a sonar that uses a receiver with single directivity over the entire circumference of 360 degrees, structures other than the transmitter and receiver Due to the influence, phasing processing may not be performed as expected and normal sonar output may not be obtained. Note that phasing processing refers to giving a required time delay or phase compensation to the output of each transducer in the formation of a received acoustic beam (beamforming).

SUMMARY OF THE INVENTION An object of the present invention is to provide a sonar device, a sonar signal processing method, and a program that can obtain a normal sonar output by suppressing the influence of structures other than transducers.

According to one aspect of the present invention, it is possible to apply single directivity generation processing capable of directing a null in any direction, and a transmitting/receiving wave formed by annularly arranging a plurality of transducers having sensitivity in the entire circumference. A device array is provided.

According to another aspect of the present invention, unidirectional directivity generation processing capable of directing nulls in any direction is applicable, and a plurality of transducers having omnidirectional sensitivities are arranged two-dimensionally or three-dimensionally. A sonar transducer having a transducer array is provided.

According to another aspect of the present invention, there is provided a transducer array in which a plurality of transducers having sensitivity over the entire circumference are arranged in an annular shape, and a received signal at each transducer of the transducer array. , a single directivity generation processing unit that individually performs single directivity generation processing that can direct nulls in any direction for each transducer, and a signal that has been individually subjected to the single directivity generation processing A sonar device is provided that includes a receive processor that includes a phasing processor that performs phasing with a receiver.

According to another aspect of the present invention, a received signal at each transducer of a transducer array in which a plurality of transducers having sensitivity over the entire circumference are arranged in an annular shape is generated in an arbitrary direction. a step of individually performing unidirectivity generation processing capable of directing a null for each transducer;
a step of performing phasing processing on the signals that have been individually subjected to the unitary directivity generation processing;
A sonar signal processing method is provided, comprising:

According to another aspect of the present invention, a received signal at each transducer of a transducer array in which a plurality of transducers having sensitivity over the entire circumference are arranged in an annular shape is generated in an arbitrary direction. A process of individually performing a unidirectional directivity generation process that can direct a null for each transducer,
a process of performing a phasing process on the signals that have been individually subjected to the unidirectional directivity generation process;
A program is provided that causes a computer to execute

According to the present invention, it is possible to obtain a normal sonar output by suppressing the influence of structures other than the transducer.

It is a figure explaining the structure of one embodiment. It is a figure which illustrates an example of a structure of a transducer array of one embodiment. It is a figure explaining an example of a structure of a transducer of one embodiment. It is a figure explaining an example of composition of a transducer of one embodiment, and a receiver. FIG. 10 is a diagram for explaining unidirectional directivity generation processing according to an embodiment; FIG. 4 is a diagram schematically illustrating generation of a cardioid directivity pattern in one embodiment; It is a figure explaining phasing processing of one embodiment. FIG. 4 is a diagram illustrating an example of a three-dimensional arrangement of transducer arrays of an embodiment; FIG. 10 illustrates another example of a two-dimensional arrangement of transducer arrays of one embodiment; It is a figure explaining the structure of one embodiment.

An embodiment of the present invention will be described. Provided is a sonar device having a transducer array in which a plurality of receivers whose unidirectivity can be controlled by signal processing are arranged two-dimensionally or three-dimensionally. By using transducers whose unit directivity can be controlled by signal processing, unnecessary signals are reduced in advance, and then phasing processing is performed as a transducer array.

FIG. 1 is a diagram schematically showing the configuration of the embodiment. The sonar device 100 includes a transducer array 102 composed of a plurality of transducers 101-1 to 101-N (N is a predetermined integer of 2 or more), and transducers 101-1 to 101-N. Receivers 103-1 to 103-N for amplifying received signals received respectively and converting analog signals to digital signals, reception processor 107, display 108 for displaying sensor information, and user inputting control parameters etc. A controller 109 is provided for setting operations.

The reception processor 107 includes a plurality of unidirectional directivity generation processing units 104-1 to 104-N that perform unidirectional directivity generation processing on the received digital signals from the receivers 103-1 to 103-N, A phasing processing unit 105 that performs phasing processing on the output from the generation processing units 104-1 to 104-N, and a target detection and target display processing by signal processing the output from the phasing processing unit 105. and a sonar detection processing/display processing unit 106 that performs. If the sonar device 100 is an active sonar capable of transmission, a transmitter 110 that generates analog signals and amplifies power, and a transmission processor 111 that generates transmission timing and transmission specifications are added.

FIG. 2 is a diagram showing an example of the transducer array 102 of FIG. Transducer 201 in FIG. 2 corresponds to one of transducers 101-1 to 101-N in FIG. Each transducer 201 is composed of a cylindrical transducer, and a plurality of transducers 201 are arranged annularly on a two-dimensional plane. Here, a structure 202 other than the sonar device may exist inside the transducer array 102 arranged in an annular shape.

FIG. 3 is a diagram showing an example of the configuration of the transducer 201 in FIG. 2, and the transducer 301 corresponds to the transducer 201 in FIG. The transducer 301 is composed of a cylindrical piezoelectric element, and is equally divided into four portions (locations) 301-1 to 301-4 (the circumference is divided into four at every 90 degrees, and each section portions 301-1 to 301-4 are arranged). The portions (locations) 301-1 to 301-4 are also electrically isolated from each other. Four voltages corresponding to the received sonar signals can be individually extracted from each of the four divided points.

FIG. 4 is a diagram showing an illustrative, non-limiting example of connections between the transducer 301 of FIG. 3 and the receiver (103 of FIG. 1). In FIG. 4, transducer 401 (consisting of four parts 401-1 to 404-4) corresponds to transducer 301 (consisting of four parts 301-1 to 301-4) in FIG. 4 shows the cylindrical transducer 301 of FIG. 3 as a schematic cross section viewed from above.

As shown in FIG. 4, four voltages are output from the transducers 401 (401-1 to 401-4). Each of the four voltages output from the transducer 401 (401-1 to 401-4) is connected to transmission/reception switches 402-1 to 402-4 for switching with the transmission signal, and the transducer 401 (401- 1 to 401-4), preamplifiers 403-1 to 403-4 for amplifying the signals (voltage) received respectively, and ADs for converting the analog signals output from the preamplifiers 403-1 to 403-4, respectively, into digital signals. It is sent to the reception processor (107 in FIG. 1) as a digital signal (data) via converters 404-1 to 404-4.

FIG. 5 is a diagram for explaining directivity by the unitary directivity generation processing unit 104 in FIG. In FIG. 5, each of transducers 501, 503, and 505 corresponds to transducer 401 in FIG. be done.

In the unidirectional directivity generation process, cardioid directivity patterns 502, 504, and 506 are generated in the horizontal plane from the four digital signals output from each of the transducers 501, 503, and 505 by cardioid processing. Transducer/receiver unit output data with each is generated. A cardioid directivity pattern in the unitary directivity generation process may be generated, for example, as follows. FIG. 6 is a diagram schematically explaining an example of generation of a cardioid directivity pattern in the unitary directivity generation process.

Transducers 401-1 to 401-4 (401-1 to 401-4 in FIG. 4) in FIG. 6A function as an omnidirectional transducer as a whole. It has an omnidirectional pattern as shown (a circle of radius 1 with the origin at the center: uniform sensitivity all around). Two transducers, transducer 401-1 and transducer 401-3, which are arranged opposite to each other along the Y-axis direction (for example, front and back) in FIG. For example, as shown in FIG. 6(C), a directivity pattern represented by cos θ (radius 1 /2). Two transducers, transducer 401-2 and transducer 401-4, which are arranged opposite to each other along the X-axis direction (for example, left and right) in FIG. For example, as shown in FIG. 6(D), a directivity pattern represented by sin θ (radius 1 /2). FIG. 6(E) is obtained by adding the received wave level of the omnidirectional pattern receiver of FIG. 6(B) and the received wave level of the directional pattern receiver of FIG. As shown in
1 + cos(θ) (1)
Transducer/receiver unit output data having directivity (cardioid type directivity) represented by is output. The cardioid directional patterns 502, 504, 506 are most sensitive to a predetermined direction (e.g., θ=0) in a reference plane (e.g., a horizontal plane) and the opposite direction to the predetermined direction in the reference plane. There is a null sensitivity to (θ=π).

When null sensitivity is set in an arbitrary direction on the XY plane (null sensitivity direction = azimuth α), as described in Patent Document 1, the omnidirectional pattern of FIG. is multiplied by cos α, and the result of multiplying the received wave level of the receiver of the directivity pattern of FIG. 6(C) by sin α is added.
cosθcosα＋sinθsinα=cos(θ-α) (2)
Subtracting the above addition result cos(θ-α) from the received wave level of the omnidirectional pattern receiver shown in FIG. 6B, the directional pattern is
1-cos(θ-α) (3)
becomes 0 at the direction θ=α, that is, the sensitivity is null. For the cardioid directivity pattern of formula (1), the addition result cos(θ-α) of formula (2) is added to the received wave level of the receiver of the omnidirectional pattern of FIG. 6(B). value
1 + cos(θ-α) (4)
is 0, that is, the sensitivity may be set to null at the azimuth θ=α+π.

In FIG. 5, in the configuration shown in FIG. 2 (a structure 202 is arranged in the middle of a plurality of cylindrical transducers 201 arranged in an annular shape), a transducer corresponding to the transducer 201 in FIG. The directional patterns 502, 504, 506 of each of the devices 501, 503, 505 are set to have null sensitivity in the direction of the structure 202 of FIG.

Here, for each of the plurality of transducers, the unidirectional directivity is measured in the same direction as the main pole (main lobe: including the point of maximum sensitivity of the directivity pattern, and between two adjacent points where the sensitivity is minimal). ), but it is also possible to adaptively direct the null to the direction in which the level of unnecessary signals such as noise is high.

FIG. 7 is a diagram for explaining the phasing processing of the phasing processing unit 105 in FIG. 1, and is a diagram for explaining the directivity of the beam output from the phasing processing unit 105. The transducers 601, 602, 603 correspond to the transducers 501, 503, 505 in FIG.

From the transducers 601, 602, and 603, phasing is performed on the transducer-unit output data (unitary directivity patterns 502, 504, and 506 in FIG. 5) generated by the unitary directivity generation processing unit 104 in FIG. Processing is performed to produce a beam output having a directional pattern 604 . Here, the phasing processing unit 105 can perform phasing processing such as adaptive beam forming in addition to phasing processing by general delay addition.

The sonar detection processing/display processing unit 106 in FIG. 1 performs sonar detection processing such as frequency analysis, correlation processing, threshold processing, and machine learning from the beam output output from the phasing processing unit 105, and sonar detection processing such as B scope and BTR. The display device 108 notifies the user of the result of display processing. The display 108 in FIG. 1 is a display device such as a liquid crystal display, and a display screen (B-scope display screen) (not shown) has an azimuth on the horizontal axis and a distance on the vertical axis. Alternatively, in a BTR (bearing-time recorder) display, the horizontal axis may be azimuth, the vertical axis may be time, and the signal strength may be displayed in gradation (intensity of display luminance).

According to this embodiment, by controlling the unidirectional directivity so that the level of unnecessary signals is lowered, the effects of reflections from surrounding structures, etc., are suppressed in the phasing process performed on the transducer array. and the sonar reception process can be performed normally.

In the above-described embodiment, an example of an array in which transducers are arranged annularly on a two-dimensional plane has been described, but the present invention is of course not limited to a two-dimensional array. For example, as shown in FIG. 8, a cylindrical array in which transducers 701 are arranged three-dimensionally can be used. In this case, the reception processor 107 of FIG. 1 is provided for the transducers 701 arranged in five stages in the vertical direction of each cylindrical array, and the same stage (horizontal direction) of the fifteen cylindrical arrays arranged in an annular shape is provided. The receiving processor 107 of FIG. 1 may be provided for the transducer 701 of FIG. 1 to perform three-dimensional phasing processing in the horizontal and vertical directions.

Moreover, even when a plurality of transducers are arranged on a two-dimensional plane, the array may be arranged in an arbitrary shape, such as a horseshoe arrangement, as shown in FIG.

In the above-described embodiment, in the unidirectional directivity generation process, an example was described in which a cardioid directivity pattern was used as a directivity pattern having null sensitivity in an arbitrary direction. Instead, depending on the application, for example, adaptive beamforming disclosed in Patent Document 2 or the like may be used.

FIG. 10 is a diagram illustrating an embodiment of the present invention, and is a diagram illustrating a configuration when implemented in a computer device (data processing device, processor device) 900. As shown in FIG. Referring to FIG. 10, a computer device 900 includes a processor 901, semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory) (or HDD (Hard Drive)). It receives digital signals from a memory 902 of a disk drive, a solid state drive (SSD), a display device 903, and the receiver 103 in FIG. It has an interface 904 (bus interface) for transmission. The processor 901 may be a DSP (Digital Signal Processor). By executing the program stored in the memory 902, the processor 901 performs, for example, the reception processor 107 (unidirectional directivity generation processing, phasing processing, sonar detection/display processing) and the transmission processor 111 in FIG. Execute the process. The display device 903 is used as the display device 108 for displaying the sonar display processing result output from the reception processor 107 .

The disclosures of Patent Documents 1 and 2 mentioned above are incorporated herein by reference. Within the framework of the full disclosure of the present invention (including the scope of claims), modifications and adjustments of the embodiments and examples are possible based on the basic technical concept thereof. Also, various combinations and selections of various disclosure elements (including each element of each claim, each element of each embodiment, each element of each drawing, etc.) are possible within the scope of the claims of the present invention. . That is, the present invention naturally includes various variations and modifications that can be made by those skilled in the art according to the entire disclosure including claims and technical ideas.

100 sonar devices 101-1 to 101-N transducer 102 transducer array 103-1 to 103-N receiver 107 reception processor 108 indicator (display)
109 controller
104-1 to 104-N unidirectional directivity generation processing unit 105 phasing processing unit 106 sonar detection processing/display processing unit 107 reception processing unit 108 display unit 110 transmitter 111 transmission processing unit 201 transducer 202 structure other than sonar 301, 401, 501, 503, 505, 601, 602, 603 transducers 301-1 to 301-4, 401-1 to 401-4 transducers (partial)
402-1 to 402-4 Transmission/reception switches 403-1 to 403-4 Preamplifiers 404-1 to 404-4 AD converters 502, 504, 506, 604 Directivity patterns 701, 801 Transceiver 900 Computer device 901 Processor 902 Memory 903 display device 904 interface

Claims (10)

1. A transducer array in which a plurality of transducers having omnidirectional sensitivities are arranged in an annular shape to which unidirectional directivity generation processing capable of directing nulls in any direction can be applied. A sonar transmission/reception having a transducer array in which a plurality of, two-dimensionally or three-dimensionally arranged transducers having sensitivity in all directions are applicable to unidirectional directivity generation processing capable of directing a null in any direction. vessel. a transducer array in which a plurality of transducers having sensitivity all around are arranged in an annular shape;
a receiving processor;
with
The receiving processor,
A plurality of unitary directivity generation processing units that individually perform unitary directivity generation processing capable of directing a null in an arbitrary direction to a received signal at each transducer of the transducer array for each transducer. and,
a phasing processing unit that performs phasing processing on signals that have been individually subjected to unitary directivity generation processing by the plurality of unitary directivity generation processing units;
a sonar device, including 4. The sonar apparatus according to claim 3, wherein said reception processor comprises a signal processing section that performs target detection processing and target display processing based on the output signal from said phasing processing section. 5. A sonar apparatus according to claim 3, wherein said transducer comprises a plurality of electrically isolated partial transducers equally dividing the circumference of the circular cross section. The unitary directivity generation processing unit has maximum sensitivity in a predetermined direction within the reference plane based on the received signals from the plurality of partial transducers in the transducer, and 6. The sonar device of claim 5, outputting data having a cardioid directional pattern with null sensitivity in a direction opposite to the direction. The sonar apparatus according to any one of claims 3 to 6, wherein said transducer array comprises a plurality of said transducers arranged two-dimensionally or three-dimensionally. Unitary directivity generation processing capable of directing a null in any direction for the received signal at each transducer of a transducer array in which a plurality of transducers with sensitivity over the entire circumference are arranged in an annular shape. a step performed individually for each transducer;
a step of performing phasing processing on the signals that have been individually subjected to the unitary directivity generation processing;
sonar signal processing methods including; 9. The sonar signal processing method according to claim 8, wherein target detection processing and target display processing are performed based on the phasing-processed signal. A unitary directivity generation process that can direct a null in any direction to the received signal at each transducer of a transducer array in which a plurality of transducers with sensitivity over the entire circumference are arranged in an annular shape. individually for each transducer, and
a process of performing a phasing process on the signals that have been individually subjected to the unidirectional directivity generation process;
A program that makes a computer run

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