CN112629639A

CN112629639A - Twelve-arm extended super-directivity circular array for suspended sonar

Info

Publication number: CN112629639A
Application number: CN202011401835.XA
Authority: CN
Inventors: 陶林伟; 王英民; 诸国磊; 牛奕龙; 郑琨; 王奇
Original assignee: Northwestern Polytechnical University
Current assignee: Northwestern Polytechnical University
Priority date: 2020-12-02
Filing date: 2020-12-02
Publication date: 2021-04-09

Abstract

The invention relates to a twelve-arm extended super-directivity circular array for a suspended sonar, and belongs to the field of underwater acoustic sensor arrays. The device comprises a super-directional array element, expansion arms and a vertical rod, wherein the super-directional array element, the expansion arms and the vertical rod are arranged in two layers, and twelve arms on each layer are uniformly distributed on the circumference; the vertical rod is fixed at the tail end of the expansion arm and is always parallel to the underwater extension machine body; the super directional array elements are fixed on the vertical rods and move up and down along with the vertical rods, and 3 groups of super directional array elements are fixed on each vertical rod. The coverage area of the new expansion array to the detection space is increased, and the space is divided more finely, so that better space directivity can be obtained, and the quality of the formed wave beam is greatly improved compared with that of a cross array.

Description

Twelve-arm extended super-directivity circular array for suspended sonar

Technical Field

The invention belongs to the field of underwater acoustic sensor arrays, and particularly relates to a twelve-arm extended super-directivity circular array for a suspended sonar.

Background

When underwater targets are detected, tracked and positioned, an acoustic method is used as a main means. The main reason is that sound has much less propagation loss than light, electricity and magnetism, and can propagate several kilometers or dozens of kilometers underwater. In engineering practice, underwater acoustic sensors are used to collect various sounds of a target. When detecting, tracking and positioning a target, a plurality of acoustic sensors are often used to form a matrix in space according to a certain geometric position. The array has better space directivity than a single array element, the direction of a target signal can be better determined, and meanwhile, the output signal-to-noise ratio of the array is greatly improved compared with that of a single array element. Therefore, basically most underwater target detection, tracking, positioning, identification and other devices are equipped with acoustic matrixes.

At present, a cross-shaped array is adopted in a suspended sonar, as shown in fig. 1, black is an extension arm, the total number of the extension arms is 4, the extension arms are uniformly distributed in the horizontal direction, and the included angle is 90 degrees. Each extension arm has 4 hydrophones attached to it, the grey part of the figure. The total number of the hydrophone array elements is 16. The cross-shaped array is divided into a horizontal arm and a vertical arm, and 8 array elements are uniformly distributed on each arm. By totaling 16 hydrophone array elements, about 16 beams are formed in the horizontal direction by the beam forming technology, and further the spatial filtering is completed. The cross-shaped array has the advantages that the number of the array arms is only 2, and the mechanical processing, the installation and the maintenance are convenient; the salient disadvantage is that the spatial filtering is not uniform and the beam quality drops significantly in the angular portion of the two arms.

Disclosure of Invention

Technical problem to be solved

In order to overcome the defect of beam quality reduction caused by uneven spatial filtering of the conventional cross array, the invention provides a twelve-arm extended circular array of a suspended sonar, wherein the twelve-arm array is uniformly distributed in the horizontal direction, so that all beams have good performance.

Technical scheme

A twelve-arm extended circular array for hanging sonar is characterized by comprising a super-directional array element, an extension arm and a vertical rod; the expansion arms are divided into an upper layer and a lower layer, the number of each layer is 12, the 12 expansion arms are uniformly distributed on the circumference, and the included angle between every two expansion arms is 30 degrees; the vertical rod is fixed at the tail end of the expansion arm and is always parallel to the body of the underwater extension; the super-directional array element is fixed on the vertical rod and moves up and down along with the vertical rod; each vertical rod fixes 3 groups of super directional array elements.

The technical scheme of the invention is further that: the extension arm is fixed on the underwater extension through an extension mechanism and can be folded or extended; when the underwater extension device is folded, the extension arm is parallel to the underwater extension device body.

The technical scheme of the invention is further that: the 3 groups of super-directional array elements are respectively fixed at two end points and a middle point of the vertical rod.

The technical scheme of the invention is further that: the super directional array element comprises 2 acoustic sensors, and the distance between the super directional array elements is 5 mm.

The technical scheme of the invention is further that: the height of the vertical rod is 900 mm.

The technical scheme of the invention is further that: the distance between the super directional array elements in each group is 450 mm.

Advantageous effects

The invention provides a twelve-arm extended circular array for a suspended sonar, which designs the specific overall dimension of the circular array and provides a mechanical installation method of the circular array. The beam quality of the circular array is greatly improved compared with the prior cross array by utilizing the twelve-arm circular array which is uniformly distributed in space and the super directivity formed by 2 array elements.

Compared with the cross array in the prior art, 8 arms are added. The coverage area of the new expansion array to the detection space is increased, and the space is divided more finely, so that better space directivity can be obtained, and the quality of the formed wave beam is greatly improved compared with that of a cross array.

Drawings

FIG. 1 prior art cross-shaped array

Fig. 2 is a front view of the correlation between the extended array and the underwater extension, with the basic array in an extended state.

FIG. 3 is a front view of the interrelationship of the extended array and the underwater extension, with the base array in an extended state. The internal components are the same as in fig. 2.

Fig. 4 is a top view of the correlation between the extended array and the underwater extension, with the basic array in an extended state. The internal components are the same as in fig. 2.

Fig. 5 is a top view of the extended super-directional array element. The 12 spreading arms are evenly distributed in the horizontal 360-degree range and are spaced by 30 degrees. After expansion, the maximum outer diameter of the matrix is 1680 mm. Each super directional array element is 5mm in length.

Fig. 6 is a front view of the extended super-directional array element. 12 vertical rods are fixed on the 12 expansion arms, and 3 groups of super directional array elements are arranged on each vertical rod. In the vertical direction, the super directional array element spacing is 45 mm.

Fig. 7 is a relation front view of the basic array and the underwater extension set after the expansion array is folded. The parts in the figure are the same as in fig. 2. After being folded, the maximum outer diameter of the array

Fig. 8 is a front view of the relationship between the basic array and the underwater extension set after the extended array is folded. The parts in the figure are the same as in fig. 2.

1-super directional array element; 2-an extension arm; 3-a vertical pole; 4-underwater extension structure.

Detailed Description

The invention will now be further described with reference to the following examples and drawings:

as shown in fig. 2, 1 is a super-directional array element, the interior of the super-directional array element is composed of 2 acoustic sensors, the distance between the acoustic sensors is 5mm, and a super-directional processing method is utilized to form a super-directional array element; 2 is an expansion arm, and in 360 degrees in the horizontal direction, 12 expansion arms are provided in total, and every two arms are spaced by 30 degrees. The extension arm is fixed at extension mechanism under water, and extension mechanism can move from top to bottom, and when extension mechanism moved down, drive the extension arm and move down to tighten up 24 extension arms (similar to the umbrella). When the expanding mechanism moves upwards, the expanding arms are driven to move upwards, and 24 expanding arms are expanded. Can be folded or expanded. When the underwater extension machine is folded, the extension arm is parallel to the underwater extension machine body; and 3, a vertical rod is fixed at the tail end of the expansion arm and is always parallel to the body of the underwater extension. Moves up and down along with the contraction and expansion movement of the expansion arm. The super-directional array element is fixed on the vertical rod and moves up and down along with the vertical rod. Each vertical rod fixes 3 groups of super directional array elements.

Expanding array type parameters:

1) 2 layers of 12 expansion arms are manufactured in the horizontal direction, the expansion arms are evenly distributed in a space of 360 degrees at intervals of 30 degrees, and the maximum outer diameter of the expanded expansion arms is 1680 mm.

2) At the outer end of the extension arm, 12 sets of vertical rods are fixed, the height of the vertical rods being 900 mm.

3) 3 super directive property array elements are fixed on every group vertical pole, and every super directive property array element comprises 2 omnidirectional underwater acoustic sensors, and the interval is 5 mm. 3 super-directional array elements are vertically arranged at intervals of 450 mm;

4) the expansion arm is parallel to the underwater extension main body after being folded, and the maximum outer diameter is 560 +/-1 mm after being folded.

Claims

1. A twelve-arm extended circular array for hanging sonar is characterized by comprising a super-directional array element (1), an extension arm (2) and a vertical rod (3); the expansion arms (2) are divided into an upper layer and a lower layer, the number of each layer is 12, the 12 expansion arms (2) are uniformly distributed on the circumference, and the included angle between every two expansion arms (2) is 30 degrees; the vertical rod (3) is fixed at the tail end of the expansion arm (2) and is always parallel to the body of the underwater extension (4); the super-directional array element (1) is fixed on the vertical rod (3) and moves up and down along with the vertical rod (3); each vertical rod (3) is fixed with 3 groups of super directional array elements (1).

2. The twelve-arm extended circular array of suspended sonar according to claim 1, wherein the extension arms (2) are fixed to the underwater extension (4) through an extension mechanism and can be folded or extended; when the underwater extension device is expanded, the expansion arm (2) is perpendicular to the body of the underwater extension (4), and when the underwater extension device is folded, the expansion arm (2) is parallel to the body of the underwater extension (4).

3. The twelve-arm extended circular array of suspended sonar according to claim 1, wherein the 3 groups of super directional array elements (1) are respectively fixed at two end points and a middle point of the vertical rod (3).

4. The twelve-arm extended circular array of suspended sonar according to claim 1, wherein the super directional array elements (1) comprise 2 acoustic sensors with a spacing of 5 mm.

5. The twelve-arm extended circular array of suspended sonar according to claim 1, wherein the height of the vertical rods (3) is 900 mm.

6. The twelve-arm extended circular array of suspended sonar according to claim 1, wherein the distance between each group of super directional array elements (1) is 450 mm.