A V-shaped double T array sonar system integrating multi-beam detection and side scan imaging

Abstract

The application belongs to the technical field of underwater acoustic detection and sonar array, and discloses a V-shaped double-T array sonar system integrating multi-beam detection and side-scan imaging, which comprises two T-shaped arrays arranged in a V shape and having an opening angle between them; each T-shaped array comprises an arc-shaped transmitting-receiving combined array and a linear receiving array arranged orthogonally, the arc-shaped transmitting-receiving combined array comprises a plurality of array elements arranged in an arc shape and is divided into a first array element group and a second array element group. The system transmits a detection acoustic signal by the specified array elements of the arc-shaped transmitting-receiving combined array in the transmitting mode, receives a return signal by the first array element group in the side-scan receiving mode, and uses the linear receiving array for multi-beam return signal receiving, so that the integration and multiplexing of the multi-beam detection and the side-scan imaging functions are realized. The application reduces the number of independent arrays, reduces the system space occupation and engineering integration complexity, expands the underwater detection coverage range, and is suitable for underwater platforms such as UUV, AUV and ROV.

Description

Technical Field

[0001] This invention belongs to the field of underwater acoustic detection and sonar array technology, and particularly relates to a V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging. This system is suitable for underwater platforms such as unmanned underwater vehicles (UUVs), autonomous underwater vehicles (AUVs), and remotely operated underwater vehicles (ROVs). By arranging two T-shaped arrays in a V-shape, the overall coverage of multi-beam detection is expanded. Simultaneously, an arc-shaped transceiver array integrates multi-beam transmission, side-scan transmission, and side-scan reception functions, thereby reducing the number of independent sonar arrays, lowering system space requirements and engineering integration complexity, and improving array utilization and adaptability to underwater platforms. Background Technology

[0002] Multibeam sonar and side-scan sonar are essential acoustic devices for unmanned underwater vehicles (UUVs), aerial underwater vehicles (AUVs), remotely operated vehicles (ROVs), and other small underwater platforms for underwater exploration, topographic mapping, target search, and seabed imaging. Multibeam sonar typically consists of a transmitting transducer array, a receiving transducer array, a transmitting drive circuit, a receiving acquisition circuit, and a signal processing unit. Its operation generally involves the transmitting array emitting a fan-shaped sound beam with a certain opening angle underwater, while the receiving array receives echo signals from different directions. Multiple receiving beams are then generated using a multi-channel beamforming algorithm to obtain distance, azimuth, and depth information of underwater targets or seabed topography. This type of sonar system is mainly used for underwater depth sounding, topographic mapping, and target spatial positioning, and typically requires a large detection coverage area, high angular resolution, and good ranging accuracy.

[0003] Side-scan sonar typically consists of port / starboard side-scan transmitting transducer arrays, port / starboard side-scan receiving transducer arrays, transmitting / receiving circuitry, and a signal processing unit. Its operation generally involves the side-scan transducer arrays emitting acoustic pulses to both sides of the vehicle and receiving backscattered echoes from seabed or underwater targets. Based on the echo intensity and propagation time, strip-shaped acoustic images are formed on both sides. This type of sonar system is mainly used for seabed topographic imaging, target search, obstacle identification, and pipeline detection, and typically requires a large lateral coverage area, good lateral imaging capabilities, and high target recognition capabilities.

[0004] In existing technologies, multibeam sonar and side-scan sonar typically employ independent array structures and operating channels. For UUVs or small underwater platforms requiring both multibeam detection and side-scan imaging capabilities, separate multibeam transmitting arrays, multibeam receiving arrays, and port / right-side scanning transmitting and receiving arrays are usually required. These arrays are generally installed on the bow, belly, or sides of the underwater platform in the form of planar arrays, arc arrays, linear arrays, T-arrays, or port / right-side arrays, with relatively fixed transmission and reception directions and installation angles. The multibeam array primarily faces downwards or forward and downwards to form a detection sector, while the side-scan array primarily faces the port / right-side to form a lateral imaging area. Each array is structurally independent and functionally undertakes either multibeam detection or side-scan imaging tasks.

[0005] While the aforementioned existing technologies can achieve multi-beam detection and side-scan imaging, they still have the following two shortcomings in applications with small underwater platforms such as UUVs:

[0006] First, the large number of arrays and low integration make it difficult to meet the compact installation requirements of small platforms. UUV platforms have a small diameter, and both internal space and external installation area are relatively limited. If multi-beam arrays and side-scan arrays are set up separately, and the port and starboard transmitting and receiving arrays of the side-scan sonar are independent of each other, it will lead to an increase in the number of arrays, installation openings, connection channels and cables, resulting in a large system size, complex structure, high power consumption and cost, which is not conducive to the miniaturization and integrated design of the platform.

[0007] Second, the array's detection direction and coverage are relatively fixed, resulting in low array resource utilization. The detection range of existing multi-beam arrays is mainly limited by the array arrangement direction and beam opening angle, making it difficult to achieve comprehensive detection of the front, lower, and lateral regions within a limited array scale. At the same time, multi-beam transmitting arrays and side-scan transmitting arrays are usually independent of each other and cannot be reused, resulting in low utilization of the transmitting array and making it difficult to simultaneously improve detection coverage and system integration efficiency.

[0008] Therefore, there is an urgent need for a composite sonar array system suitable for small underwater platforms such as UUVs, which can simultaneously achieve multi-beam detection and side-scan transceiver functions within a limited installation space, and expand the detection coverage range through a reasonable array configuration. Specifically, it is necessary to solve the problems caused by the separate arrangement of existing multi-beam sonar and side-scan sonar, such as a large number of arrays, large space occupation, complex system structure, low array utilization, limited detection coverage, and difficulty in integrating multi-mode detection. Summary of the Invention

[0009] This invention addresses the problems of large array size, complex structure, large space occupation, limited detection range, and difficulty in reusing transmission and reception functions caused by the separate arrangement of multibeam sonar and side-scan sonar in existing small underwater platforms such as UUVs. It proposes a V-shaped arrangement dual-T array sonar system that integrates multibeam detection and side-scan transmission and reception.

[0010] To achieve the above objectives, the present invention adopts the following technical solution:

[0011] A V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging includes: two T-shaped arrays arranged in a V-shape with an opening angle X between them; each T-shaped array includes an arc-shaped transceiver array and a straight-line receiver array, the arc-shaped transceiver array and the straight-line receiver array being orthogonal to each other, the two straight-line receiver arrays being arranged in a V-shape with an included angle X, and the two arc-shaped transceiver arrays being respectively positioned in front of the straight-line receiver arrays and parallel to each other; the arc-shaped transceiver array includes multiple array elements arranged in an arc shape, the multiple array elements being divided into a first array element group and a second array element group; the arc-shaped transceiver array is configured to: in transmission mode, transmit detection acoustic signals by designated array elements; and in side-scan receiver mode, receive echo signals by the first array element group; the straight-line receiver array is configured to be used at least for multi-beam echo reception.

[0012] Furthermore, the arc-shaped transceiver array includes an arc-shaped array base and multiple transceiver array elements disposed on the arc-shaped array base. The multiple transceiver array elements are arranged sequentially along the axis of the arc-shaped array at a preset interval to form an arc-shaped geometric structure, and its sound field can be expanded within the arc angle range; the linear receiving array includes a linear base and multiple receiving array elements disposed on the linear base. The multiple receiving array elements are arranged sequentially along the linear direction at a preset interval to form a linear geometric structure.

[0013] Furthermore, the arc-shaped transceiver array is configured such that, in multi-beam transmission mode and side-scan transmission mode, a portion of the array elements in the middle region of the first array element group and a portion of the array elements in the middle region of the second array element group jointly serve as the transmission array to increase the transmission aperture and the transmission sound source level; in side-scan reception mode, only the first array element group serves as the side-scan reception array, and the second array element group does not participate in reception.

[0014] Furthermore, the first array element group and the second array element group are connected in an arc shape. The first array element group includes array elements a1 to a20 numbered sequentially along the axis of the arc-shaped transceiver array, and the second array element group includes array elements b1 to b20 numbered sequentially along the axis of the arc-shaped transceiver array. In the transmission mode, the designated array elements that jointly serve as the transmission array are a6 to a15 and b6 to b15. In the side-scan reception mode, the array elements that serve as the receiving array are a1 to a20.

[0015] Furthermore, array elements b1 to b5 and b16 to b20 in the second array element group are configured as spare array elements, which are used as needed to increase the transmitting aperture, transmitting sound source level or side-scan reception coverage; in side-scan reception mode, all array elements b1 to b20 in the second array element group are in a disconnected, isolated or idle state.

[0016] Furthermore, the linear receiving array includes multiple receiving array elements arranged sequentially along a straight line, with the spacing between each receiving array element not exceeding half the wavelength of the center operating frequency of the linear receiving array; the linear receiving array is used only as a receiving array for multi-beam sonar to receive the echo formed by the reflection of multi-beam transmitted signals by the target, and does not participate in the reception of side-scan sonar, nor is it used as any transmitting array.

[0017] Furthermore, it also includes a control circuit, a transmit / receive switching unit, and a signal processing unit. The control circuit is connected to each element of the arc-shaped transmit / receive array and is used to output a transmit excitation signal to a designated element in transmit mode and receive the electrical signal output by the corresponding element in receive mode. The transmit / receive switching unit is connected to the control circuit and is used to switch the corresponding element in the arc-shaped transmit / receive array between transmit and receive states according to the system operating mode to avoid damage to the receiving channel caused by transmitting high-voltage signals. The signal processing unit is connected to the transmit / receive switching unit and is used to perform pre-amplification, filtering, digitization, time gain compensation, beamforming, and side-scan imaging processing on the side-scan echo signals received by each element in the arc-shaped transmit / receive array to generate side-scan sonar images that reflect the seabed topography and target distribution characteristics.

[0018] Furthermore, it also includes a receiving and acquisition circuit and a signal processing unit two. The receiving and acquisition circuit is connected to each receiving element in the linear receiving array and is used to pre-amplify, filter, and acquire data from the electrical signals converted and output by each element. The signal processing unit two is connected to the receiving and acquisition circuit and is used to perform beamforming, target detection, and parameter estimation processing on the acquired multi-channel echo data to obtain the target's distance, depth, and azimuth information, and generate seabed topography and geomorphology detection results.

[0019] Furthermore, the two T-shaped arrays are arranged symmetrically or asymmetrically with respect to the central axis of the sonar system; the opening angle X is set according to the target detection coverage and platform installation space, and the larger the opening angle, the wider the comprehensive coverage formed by the two T-shaped arrays; the opening direction of the V-shaped array faces the target detection area, which is used to expand the comprehensive detection capability of the sonar system to the front, lower, and left and right side areas.

[0020] Furthermore, the V-shaped double-T array is installed in the bow, belly, or side mounting area of ​​the underwater vehicle; the arc-shaped transceiver array has an arc surface that matches the shape of the mounting platform to reduce the size of the protrusion from the platform; the arc-shaped transceiver array and the linear receiving array are mounted on the same mounting base or the same sonar housing to ensure a fixed positional relationship and acoustic axis consistency between the two.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] First, the present invention arranges two multi-beam T-shaped arrays in a V-shape to form an integrated V-shaped sonar array. By adjusting the opening angle X between the two T-shaped arrays, the detection coverage and spatial orientation of the sonar system can be adaptively adjusted, thereby enhancing the comprehensive detection capabilities of small underwater platforms such as UUVs in the areas below, directly below, and to both sides.

[0023] Second, each T-shaped array of the present invention consists of an arc-shaped transceiver array A1 / A2 and a linear receiver array B1 / B2. The arc-shaped transceiver array A1 / A2 combines multi-beam transmission, side-scan transmission, and side-scan reception functions, while the linear receiver array B1 / B2 is used for multi-beam echo reception. This enables the same sonar system to simultaneously perform multi-beam ranging, depth measurement, target detection, and side-scan imaging, improving the system's multi-functional integration.

[0024] Third, this invention divides the arc-shaped transceiver array A1 / A2 into a first array element group and a second array element group, and selectively calls the corresponding array elements according to different operating modes. In multi-beam transmission mode and side-scan transmission mode, designated array elements a6~a15 and b6~b15 jointly transmit the sound detection signal; in side-scan reception mode, array elements a1~a20 of the first array element group receive the echo signal. Through the above-mentioned array element partitioning and function multiplexing method, the number of independent side-scan transmission arrays and side-scan reception arrays can be reduced, and the utilization efficiency of array elements and array resources can be improved.

[0025] Fourth, this invention utilizes the arc-shaped transceiver array A1 / A2 to simultaneously perform multi-beam transmission, side-scan transmission, and side-scan reception functions, reducing the number of independent arrays in the sonar system. This helps to reduce the overall size and space occupied by the array, while also reducing the number of installation openings, connecting cables, and interfaces on the mounting platform, thus reducing the complexity of the system structure and the difficulty of engineering integration. It is especially suitable for underwater platforms such as UUVs, AUVs, and ROVs where installation space and load capacity are limited.

[0026] Fifth, this invention integrates multi-beam detection and side-scan imaging into the same sonar system by combining a V-shaped double-T array with an arc-shaped transceiver array. This allows different detection modes to share a unified installation reference and array coordinate system, which helps improve the relative position accuracy, installation reference consistency, and acoustic axis consistency between the arrays, reduces the difficulty of system installation and calibration, and facilitates the registration, fusion, and comprehensive application of multi-beam detection data and side-scan imaging data. Attached Figure Description

[0027] Figure 1 A schematic diagram of a double-T array arranged in a V-shape;

[0028] Figure 2 A schematic diagram of a single T-shaped array structure;

[0029] Figure 3 A schematic diagram of a transceiver array structure in a T-type array;

[0030] Figure 4 A schematic diagram of the array elements and signal control system in a combined transmit / receive array;

[0031] Figure 5 A schematic diagram of the arc-shaped base structure in a combined transmit / receive array;

[0032] Figure 6 A schematic diagram illustrating the functional definitions of each element in the transmit / receive array.

[0033] Figure 7 This is a schematic diagram of a multibeam sonar receiving array structure in a T-shaped array.

[0034] Figure 8 A schematic diagram of the array elements and signal control system in a multibeam sonar receiving array;

[0035] Figure 9 A schematic diagram of the base structure in a multibeam sonar receiving array;

[0036] Figure 10 A schematic diagram of the coverage area of ​​a V-shaped array multibeam detection system;

[0037] Figure 11 This is a schematic diagram of the coverage area of ​​a V-shaped array side scan imaging. Detailed Implementation

[0038] The specific embodiments of the present invention will be described in detail below. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the scope of protection of the present invention.

[0039] This invention discloses a V-shaped dual-T array sonar system integrating multi-beam detection and side-scan transceiver, comprising two multi-beam T-arrays arranged in a V-shape, with an opening angle X between the two T-arrays to form a V-shaped array. Figure 1 As shown. The opening angle X can be set according to the actual detection range, platform installation space and sonar coverage requirements. The larger the opening angle X, the wider the comprehensive coverage range formed by the two T-shaped arrays, which is more conducive to expanding the detection coverage area of ​​the sonar system in the horizontal, downward or lateral regions.

[0040] In one specific embodiment, the multi-beam T-array includes a first T-array 1 and a second T-array 2, such as Figure 1 As shown. The first T-array 1 and the second T-array 2 are arranged in a V-shape. Both the first T-array 1 and the second T-array 2 include an arc-shaped transceiver array A1 / A2 and a linear receiver array B1 / B2, as shown. Figure 2 As shown. The arc-shaped transceiver arrays A1 / A2 are mainly used to realize multi-beam sonar transmission, side-scan sonar transmission, and side-scan sonar reception functions. The linear receiver arrays B1 / B2 are mainly used to realize multi-beam sonar reception functions. The linear receiver arrays B1 and B2 are arranged in a V-shape with an angle of X (as shown). Figure 1 (As shown by the included angle of the dashed line). The arc-shaped transceiver arrays A1 and A2 are respectively positioned in front of the linear receiver arrays B1 and B2, and are arranged orthogonally to the linear receiver arrays B1 and B2 in space, with A1 and A2 being parallel to each other. The two T-shaped arrays can be arranged symmetrically with respect to the central axis of the sonar system, or they can be arranged in a non-perfectly symmetrical manner depending on the platform shape and detection requirements.

[0041] The arc-shaped transceiver array A1 / A2 and the linear receiver array B1 / B2 constitute the basic structure of a T-shaped array.

[0042] The arc-shaped transceiver array A1 / A2 serves as one arm of the T-shaped array, and its overall arrangement is arc-shaped. For example... Figure 3 As shown, the arc-shaped transceiver array A1 / A2 comprises two parts: a transceiver array element 3 and an arc-shaped array base 4. The transceiver array element 3 has an arc-shaped geometric structure, allowing its sound field to expand over a wide arc angle range. This is beneficial for forming a wider transmission coverage angle for multi-beam sonar and side-scan sonar, as well as a wider receiving area for side-scan sonar. Figure 4As shown. The arc-shaped array base 4 has a corresponding arc-shaped support structure, used to support and position the arc-shaped transceiver array elements, such as... Figure 5 As shown.

[0043] In one specific embodiment, the arc-shaped transceiver array elements 3 are arranged sequentially along the axis of the arc-shaped transceiver array. Each arc-shaped transceiver array element 3 can be a piezoelectric ceramic transducer, a 1-3 piezoelectric composite material transducer, or other electroacoustic transducer units suitable for underwater acoustic transmission and reception. The arc-shaped transceiver array elements 3 are arranged at a preset spacing, which can be determined according to the operating frequency, beamforming requirements, and grating lobe suppression requirements, and is generally no greater than half the wavelength of the center operating frequency.

[0044] The arc-shaped transceiver array is divided into a first array group and a second array group, which are connected in an arc shape. The first array group and the second array group are further divided into 20 independent array elements. Each array element has its own lead wire for connection to the back-end control circuit. The control circuit is connected to the transceiver switching unit, which is connected to the signal processing unit. Figure 4 As shown.

[0045] When the multibeam sonar / side-scan sonar system is in the transmission operation state, the excitation electrical signal generated by the control circuit is loaded onto the designated array element of the arc-shaped transceiver array A1 / A2 through the transmission link, driving the corresponding array element to complete the electro-acoustic conversion, forming a transmission beam that meets the system requirements, and realizing functions such as wide-coverage ranging, depth sounding, azimuth estimation, and seabed topography detection of targets.

[0046] When the side-scan sonar system is in receiving mode, the side-scan echo signal arrives at the arc-shaped transceiver array A1 / A2, where it is received by a designated array element. The signal is then converted from acoustic to electrical signals and processed by pre-amplification, filtering, data acquisition, and beamforming to generate multiple receiving beams. This enables side-scan detection functions such as wide-range scanning of seabed targets, target detection, classification and identification, and seabed topography imaging.

[0047] In one specific embodiment, the functions of each element in the arc-shaped transceiver array 3 are as follows: Figure 6 As shown.

[0048] The array elements in the first array group are numbered a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, and a20, respectively, according to the diagram. The array elements in the second array group are numbered b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14, b15, b16, b17, b18, b19, and b20, respectively, according to the diagram.

[0049] Preferably, when array elements numbered a6, a7, a8, a9, a10, a11, a12, a13, a14, and a15 work together with array elements numbered b6, b7, b8, b9, b10, b11, b12, b13, b14, and b15, they can serve as a common transmitting array for both multi-beam sonar and side-scan sonar, thereby improving the transmission coverage, transmission aperture, and transmission sound source level, and transmitting sound signals to the target detection area.

[0050] As a preferred method, the transmission and reception functions of multi-beam sonar / side-scan sonar share a single array in a time-division manner, which can increase the space utilization of the sonar system.

[0051] Preferably, when the array elements numbered a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, and a20 work together, they can serve as the receiving array of a side-scan sonar to increase the receiving aperture and improve the resolution of the received signal, and to receive the echo signal emitted by the transmitting array.

[0052] Preferably, in side-scan sonar receiving mode, only the first array element in the arc-shaped transceiver array A1 / A2 operates independently, serving as the receiving array for the side-scan sonar. The second array element is not used as a receiving array in this mode and can be in a disconnected, isolated, idle, or other non-receiving state. In this way, the transmitting and receiving functions of the multi-beam sonar / side-scan sonar share a single array in a time-division manner, increasing the space utilization of the sonar system and avoiding the need for an additional independent side-scan receiving array.

[0053] Preferably, array elements numbered b1, b2, b3, b4, b5 and b16, b17, b18, b19, b20 are used as spare array elements. When it is necessary to increase the aperture and transmission source level of the multi-beam sonar and side-scan sonar transmitting section, or to increase the coverage of the side-scan sonar receiving section, the corresponding spare array elements can be called as needed to improve the corresponding performance of the multi-beam sonar and side-scan sonar.

[0054] The linear receiver arrays B1 / B2 serve as another arm of the T-array, and are arranged along a straight line. For example... Figure 7 As shown, in a specific embodiment, the linear receiving array B1 / B2 comprises two parts: receiving array element 5 and receiving array base 6.

[0055] The receiving array element 5 consists of linearly arranged, linearly oriented elements. The element spacing is related to the center operating frequency of the multi-beam sonar array and is generally no greater than half the wavelength of the center frequency. Each receiving array element has an independent lead wire for connection to the downstream signal acquisition circuit. The signal acquisition circuit is connected to signal processing unit two, such as... Figure 8 As shown.

[0056] The receiving array base 6 is a cuboid structure with internal slots for supporting and positioning the receiving array elements. Figure 9 As shown.

[0057] When the multibeam sonar system is in receiving mode, the echo signal emitted by the multibeam transmitting array reaches the linear receiving array B1 / B2. The array elements of the linear receiving array B1 / B2 complete the acoustic-to-electric conversion. The output electrical signal is then processed by preamplification, filtering, data acquisition and beamforming to form multiple receiving beams, realizing multibeam detection functions such as accurate ranging, depth measurement, azimuth estimation and seabed topography detection of targets.

[0058] As a preferred option, the linear receiving arrays B1 / B2 are used only as receiving arrays for multi-beam sonar, and do not participate in side-scan sonar reception or as transmitting arrays, thus making the functional division of different array parts clearer.

[0059] In a specific example, to achieve the switching between different operating modes of the arc-shaped transceiver array A1 / A2, the sonar system of the present invention may further include control circuitry, a transceiver switching unit, and a signal processing unit, etc. Figure 4 As shown. The control circuit is connected to the arc-shaped transceiver array A1 / A2, used to output transmission excitation signals to the corresponding array elements in multi-beam transmission mode and side-scan transmission mode, or to receive the acoustic wave signals output by the corresponding array elements in side-scan reception mode. The transceiver switching unit is connected to the control circuit, used to switch the corresponding array elements in the arc-shaped transceiver array A1 / A2 between transmission and reception states to avoid damage to the receiving channel caused by the transmission high-voltage excitation signal. The signal processing unit is connected to the transceiver switching unit, used to process the acoustic wave signals received by each array element in the arc-shaped transceiver array A1 / A2, including but not limited to signal amplification, filtering, digitization conversion, beamforming, target detection, and imaging processing, thereby acquiring detection data of the target area.

[0060] In a specific example, to enable the linear receiving array B1 / B2 to receive and process multi-beam echo signals, the sonar system of the present invention may further include a receiving and acquisition circuit and a signal processing unit. The receiving and acquisition circuit is connected to each receiving element in the linear receiving array B1 / B2 and is used to pre-amplify, filter, and acquire data from the electrical signals output by each element. The signal processing unit is connected to the receiving and acquisition circuit and is used to perform beamforming, target detection, and parameter estimation processing on the acquired multi-channel echo data, thereby obtaining information such as target distance, depth, and azimuth, and subsequently generating seabed topography and geomorphology detection results.

[0061] In terms of structural installation, in the V-shaped array, the arc-shaped transceiver array A1 / A2 of the first T-shaped array / second T-shaped array and the linear receiving array B1 / B2 can be set on different mounting bases, or they can be set on the same mounting base, mounting bracket or sonar housing to ensure that the two have a fixed positional relationship and acoustic axis relationship.

[0062] Preferably, the two T-shaped arrays are arranged in a V-shape, and the detection areas of the two single-sided T-shaped arrays can form a combined coverage in space, thereby expanding the overall multi-beam detection range.

[0063] In terms of structural installation, the two multi-beam T-arrays can be installed in the bow, belly, or side mounting areas of the UUV platform.

[0064] Preferably, the opening direction of the V-shaped array can be set according to the platform's navigation direction and detection requirements. For example, when it is necessary to expand the combined detection range to the front, lower, left, and right sides, the two T-shaped arrays can be arranged to the left and right relative to the longitudinal centerline of the platform, so that the V-shaped opening faces the target detection area.

[0065] Preferably, the arc-shaped transceiver array A1 / A2 can be arranged close to the surface of the platform shell, and its arc surface is adapted to the shape of the platform to reduce the size of the protrusion of the platform shape; the linear receiver array B1 / B2 can be arranged along the horizontal, vertical or diagonal of the platform, and form a T-shaped structure with the arc-shaped transceiver array A1 / A2.

[0066] Specific Examples of the Invention

[0067] like Figure 1 As shown, this embodiment provides a V-shaped dual-T array sonar system with integrated multi-beam detection and side-scan transceiver suitable for UUV platforms.

[0068] The system includes a first T-shaped array on the left and a second T-shaped array on the right. The first and second T-shaped arrays respectively include an arc-shaped transceiver array A1 / A2 and a linear receiver array B1 / B2, as shown below. Figure 2 As shown.

[0069] The arc-shaped transceiver array A1 / A2 includes transceiver array elements, an arc-shaped array base, control circuitry, a transceiver switching unit, and a signal processing unit, such as... Figure 3 , Figure 4 , Figure 5 As shown.

[0070] The linear receiver array B1 / B2 includes receiver array elements, a receiver array base, acquisition circuitry, and a signal processing unit. Figure 7 , Figure 8 , Figure 9 As shown.

[0071] The first T-shaped array on the left and the second T-shaped array on the right are arranged in a V-shape, forming an opening angle X between them. The opening angle X can be determined according to the external dimensions of the UUV platform, the target detection width, and the side scan coverage requirements. For example, it can be set to 30°, 60°, 90°, or other angles that meet the detection requirements. The larger the opening angle X, the wider the combined coverage area of ​​the two T-shaped arrays; the smaller the opening angle X, the more concentrated the detection area of ​​the two T-shaped arrays.

[0072] The transmit / receive array elements in the arc-shaped transmit / receive array A1 / A2 are arranged along the array axis and together with the arc-shaped array base, they form the arc-shaped transmit / receive array A1 / A2.

[0073] The functional definitions of each element in the transmit / receive combined array are as follows: Figure 6 As shown.

[0074] The array elements numbered a6, a7, a8, a9, a10, a11, a12, a13, a14, and a15, and the array elements numbered b6, b7, b8, b9, b10, b11, b12, b13, b14, and b15 (hereinafter referred to as a6~a15 and b6~b15) in the transceiver array are the transmitting part, mainly participating in the multi-beam sonar transmission and side-scan sonar transmission functions, jointly transmitting acoustic signals to the underwater target area.

[0075] The array elements numbered a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, and a20 (hereinafter referred to as a1~a20) in the transceiver array are the receiving part, mainly participating in the side-scan sonar receiving function.

[0076] The array elements numbered a6, a7, a8, a9, a10, a11, a12, a13, a14, and a15 in the combined transmit and receive array are shared components, which can participate in both transmission and side-scan reception.

[0077] 1. Multi-beam sonar / side-scan sonar transmission function

[0078] During multi-beam sonar / side-scan sonar transmission, after receiving the transmission command from the transmit / receive switching unit, the control circuit in the arc-shaped transmit / receive array A1 / A2 transmits the excitation electrical signal to... Figure 6 In the specific transceiver array element, the corresponding array element converts the electrical signal into an acoustic signal, enabling multi-beam sonar / side-scan sonar to detect acoustic illumination of target areas on the left and right sides.

[0079] Since the first T-array and the second T-array are arranged in a V-shape, the transmission coverage areas of the arc-shaped transceiver arrays A1 and A2 complement each other, thereby expanding the overall detection coverage of the multi-beam sonar / side-scan sonar.

[0080] 2. Multibeam sonar receiving function

[0081] When the multibeam sonar is in operation, the receiving array elements in the linear receiving array B1 / B2 receive the target or seabed echo signal and convert the acoustic signal into an electrical signal. The receiving and acquisition unit amplifies, filters and samples the electrical signal before sending it to the signal processing unit.

[0082] Signal processing unit 2 performs beamforming processing on the multi-channel signals received by B1 / B2 to form multiple receiving beams, and generates side-scan sonar images based on echo intensity, propagation time, and platform motion information, ultimately realizing multi-beam ranging, depth sounding, or underwater target detection functions.

[0083] When a V-shaped dual-T array sonar system is in operation, its multi-beam detection coverage area is as follows: Figure 10 As shown, the first T-shaped array and the second T-shaped array form fan-shaped detection areas facing different directions. The two detection areas are connected and partially overlapped directly below the V-shaped array, thus forming a comprehensive multi-beam detection area with a larger lateral coverage and better continuity. This is beneficial for expanding the detection range of the sonar system in the areas directly below, diagonally below, and to both sides.

[0084] 3. Side-scan sonar receiving function

[0085] During side-scan sonar reception, after receiving the reception command from the transmit / receive switching unit, the control circuit in the arc-shaped transceiver array A1 / A2 uses, as follows: Figure 6 The specific transceiver array element receives backscattered echoes from seabed or underwater targets and transmits the echo signals to the control circuit. The control circuit converts the acoustic signals into electrical signals and transmits them to the signal processing unit.

[0086] Signal processing unit 2 generates side-scan sonar images based on echo intensity, propagation time, and platform motion information, thereby realizing the side-scan sonar detection and reception function.

[0087] Since the first T-shaped array and the second T-shaped array are arranged in a V-shape, the receiving coverage areas of the arc-shaped transceiver arrays A1 / A2 complement each other, thereby expanding the overall side-scan sonar detection coverage.

[0088] When a V-shaped dual-T array sonar system is in operation, its side-scan imaging coverage area is as follows: Figure 11 As shown, the first T-shaped array and the second T-shaped array form lateral fan-shaped detection areas on the left and right sides of the V-shaped array, respectively, to simultaneously scan the seabed and underwater targets on both sides of the platform. This constitutes a dual-side scan imaging coverage area that is independent and complementary in direction, which is beneficial to expanding the lateral detection range of the system and improving the imaging efficiency of the port and starboard sides.

[0089] In this embodiment, the arc-shaped transceiver array A1 / A2 performs three functions:

[0090] First, in the multi-beam sonar operating mode, array elements a6~a15 and b6~b15 are designated as the transmitting array of the multi-beam sonar.

[0091] Second, in the side-scan sonar operating mode, array elements a6~a15 and b6~b15 are designated as the transmitting array of the side-scan sonar.

[0092] Third, in the side-scan sonar receiving mode, its first array element group a1~a20 is used as the side-scan receiving array.

[0093] In this embodiment, the linear receiver arrays B1 / B2 only perform the function of multi-beam sonar reception.

[0094] With the above functional allocation, the sonar system does not need to set up separate multi-beam sonar transmitting arrays, side-scan sonar transmitting arrays, and side-scan sonar receiving arrays, thereby reducing the number of arrays and the space occupied for installation.

[0095] The workflow of this embodiment may include the following steps:

[0096] Step 1: Select working mode.

[0097] The system can select from the following modes based on mission requirements: multi-beam detection mode, side-scan imaging mode, or simultaneous multi-beam detection and side-scan imaging mode.

[0098] Step 2, multi-beam detection mode.

[0099] When the system selects the multi-beam detection mode, the arc-shaped transceiver array A1 / A2 is switched to transmit mode via the transmit / receive switching unit. The control circuit outputs transmit excitation signals to designated array elements a6-a15 and b6-b15 in the arc-shaped transceiver array A1 / A2, driving these elements to jointly transmit multi-beam detection acoustic signals. The echo signals formed by the target or seabed reflection are received by the linear receiving array B1 / B2 and converted into multi-channel electrical signals through acoustic-to-electric conversion. Subsequently, the signal processing unit performs pre-amplification, filtering, data acquisition, beamforming, and parameter estimation on the multi-channel electrical signals to obtain information such as target distance, depth, and azimuth, or to generate seabed topography detection results.

[0100] Step 3, side scan imaging mode.

[0101] When the system selects the side-scan imaging mode, the arc-shaped transceiver array A1 / A2 is first switched to the transmit state via the transmit / receive switching unit. The control circuit outputs transmit excitation signals to designated array elements a6-a15 and b6-b15 in the arc-shaped transceiver array A1 / A2, driving these elements to jointly transmit side-scan detection acoustic signals. After transmission, the arc-shaped transceiver array A1 / A2 is switched to the receive state via the transmit / receive switching unit. The first array element group a1-a20 in the arc-shaped transceiver array A1 / A2 receives the echo signals reflected from the seabed and underwater targets, and completes the acoustic-to-electric conversion. The signal processing unit performs pre-amplification, filtering, data acquisition, time gain compensation, and side-scan imaging processing on the multi-channel echo data output by the array elements, thereby generating a side-scan sonar image reflecting the seabed topography, target distribution, and target morphological characteristics.

[0102] Step 4: Synchronous operation mode of multi-beam detection and side-scan imaging.

[0103] When the system selects the multi-beam detection and side-scan imaging synchronous working mode, it first determines the expected arrival time of the echo signal based on the preset detection distance, and sets the pulse width and transmission / reception timing of the transmitted excitation signal accordingly to avoid time overlap between the transmitted signal and the received echo signal. Subsequently, the detection acoustic signal is transmitted using designated array elements a6~a15 and b6~b15 in the arc-shaped transceiver array A1 / A2; the echo signals formed by the target and seabed reflections are synchronously received by the linear receiving array B1 / B2 and the first array element group a1~a20 in the arc-shaped transceiver array A1 / A2, respectively. The obtained echo data are used for multi-beam detection processing and side-scan imaging processing, respectively.

[0104] The above specific examples are merely preferred embodiments of the present invention. In other embodiments, the radius of curvature, number of elements, element spacing, arc array length, and number and length of elements in the V-shaped opening angle X, the arc transceiver array A1 / A2, and the linear receiving array B1 / B2 can all be adjusted according to the operating frequency, target detection range, platform size, and imaging resolution requirements. The number of elements in the first and second array elements groups can also be the same or different. The first array element group can be located on the inner side, middle, end, or near the side scan main detection direction of the arc transceiver array A1 / A2. The ratio of the first and second array elements groups can also be adjusted according to the different coverage areas of the multibeam sonar / side scan sonar, as long as it can realize its function as a side scan receiving array.

[0105] The above-described specific embodiments are merely one of the preferred embodiments of the present invention and do not constitute a limitation on the scope of protection of the present invention. In other embodiments, the opening angle X of the V-shaped array, the radius of curvature, number of array elements, element spacing, and length of the arc-shaped transceiver array A1 / A2, as well as the number of array elements, element spacing, and array length of the linear receiving array B1 / B2, can all be adaptively adjusted according to requirements such as system operating frequency, target detection range, platform size, detection coverage, and imaging resolution.

[0106] In the arc-shaped transceiver array A1 / A2, the number of array elements in the first array element group and the second array element group can be the same or different. The first array element group can be located on the inner side, middle, or end of the arc-shaped transceiver array A1 / A2, or on the side close to the main detection direction of the side-scan sonar. The volume ratio, arrangement position, and coverage area of ​​the first array element group and the second array element group can also be adjusted according to the different multi-beam detection area and side-scan imaging area. As long as the first array element group can serve as a side-scan receiving subarray to receive echo signals and cooperate with other array elements to realize the corresponding functions of multi-beam sonar and side-scan sonar, it should be considered an optional embodiment of the present invention.

[0107] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging, characterized in that, include: Two T-shaped arrays are arranged in a V-shape with an opening angle X between them. Each T-shaped array includes an arc-shaped transceiver array and a straight-line receiver array. The arc-shaped transceiver array and the straight-line receiver array are arranged orthogonally. The two straight-line receiver arrays are arranged in a V-shape with an included angle X. The two arc-shaped transceiver arrays are respectively positioned in front of the straight-line receiver arrays and are parallel to each other. The arc-shaped transceiver array contains multiple array elements arranged in an arc shape, which are divided into a first array element group and a second array element group. The arc-shaped transceiver array is configured to: transmit a sound detection signal by a designated array element in transmit mode; and receive an echo signal by the first array element group in side-scan receive mode. The straight-line receiver array is configured to be used for at least multi-beam echo reception.

2. The V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging according to claim 1, characterized in that, The arc-shaped transceiver array includes an arc-shaped array base and multiple transceiver array elements disposed on the arc-shaped array base. The multiple transceiver array elements are arranged sequentially along the axis of the arc-shaped array at a preset interval to form an arc-shaped geometric structure, and its sound field can be expanded within the arc angle range. The linear receiving array includes a linear base and multiple receiving array elements disposed on the linear base. The multiple receiving array elements are arranged sequentially along the linear direction at a preset interval to form a linear geometric structure.

3. The V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging according to claim 1, characterized in that, The arc-shaped transceiver array is further configured such that, in multi-beam transmission mode and side-scan transmission mode, a portion of the array elements in the middle region of the first array element group and a portion of the array elements in the middle region of the second array element group jointly serve as the transmission array to increase the transmission aperture and the transmission sound source level; in side-scan reception mode, only the first array element group serves as the side-scan reception array, and the second array element group does not participate in reception.

4. The V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging according to claim 3, characterized in that, The first array element group and the second array element group are connected in an arc shape. The first array element group includes array elements a1 to a20 numbered sequentially along the axis of the arc-shaped transmit and receive array. The second array element group includes array elements b1 to b20 numbered sequentially along the axis of the arc-shaped transmit and receive array. In the transmit mode, the designated array elements that jointly serve as the transmit array are a6 to a15 and b6 to b15. In the side-scan receive mode, the array elements that serve as the receive array are a1 to a20.

5. The V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging according to claim 4, characterized in that, Elements b1 to b5 and b16 to b20 in the second array element group are configured as spare array elements, which are used as needed to increase the transmitting aperture, transmitting sound source level or side scan reception coverage; in side scan reception mode, all array elements b1 to b20 in the second array element group are in a disconnected, isolated or idle state.

6. The V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging according to claim 1, characterized in that, The linear receiving array comprises multiple receiving array elements arranged sequentially along a straight line, with the spacing between each receiving array element not exceeding half the wavelength of the center operating frequency of the linear receiving array. The linear receiving array is used only as a receiving array for multi-beam sonar to receive the echo formed by the reflection of multi-beam transmitted signals by the target. It does not participate in the reception of side-scan sonar, nor is it used as any transmitting array.

7. The V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging according to claim 1, characterized in that, It also includes a control circuit, a transmit / receive switching unit, and a signal processing unit. The control circuit is connected to each element of the arc-shaped transmit / receive array and is used to output a transmit excitation signal to a designated element in transmit mode and receive the electrical signal output by the corresponding element in receive mode. The transmit / receive switching unit is connected to the control circuit and is used to switch the corresponding element in the arc-shaped transmit / receive array between transmit and receive states according to the system operating mode to avoid damage to the receiving channel caused by transmitting high-voltage signals. The signal processing unit is connected to the transmit / receive switching unit and is used to perform pre-amplification, filtering, digitization, time gain compensation, beamforming, and side-scan imaging processing on the side-scan echo signals received by each element in the arc-shaped transmit / receive array to generate side-scan sonar images that reflect the seabed topography and target distribution characteristics.

8. The V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging according to claim 1, characterized in that, It also includes a receiving and acquisition circuit and a signal processing unit two. The receiving and acquisition circuit is connected to each receiving element in the linear receiving array and is used to pre-amplify, filter and acquire data of the electrical signals converted and output by each element. The signal processing unit two is connected to the receiving and acquisition circuit and is used to perform beamforming, target detection and parameter estimation processing on the acquired multi-channel echo data to obtain the target's distance, depth and azimuth information and generate seabed topography and geomorphology detection results.

9. The V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging according to claim 1, characterized in that, The two T-shaped arrays are arranged symmetrically or asymmetrically with respect to the central axis of the sonar system; the opening angle X is set according to the target detection coverage and platform installation space. The larger the opening angle, the wider the comprehensive coverage formed by the two T-shaped arrays; the opening direction of the V-shaped array faces the target detection area, which is used to expand the comprehensive detection capability of the sonar system to the front, lower, and left and right side areas.

10. The V-shaped dual-T array sonar system integrating multi-beam detection and side-scan imaging according to claim 1, characterized in that, The V-shaped double-T array is installed in the bow, belly, or side mounting area of ​​the underwater vehicle; the arc-shaped transceiver array has an arc surface that matches the shape of the platform to reduce the size of the protrusion from the platform; the arc-shaped transceiver array and the linear receiver array are mounted on the same mounting base or the same sonar housing to ensure a fixed positional relationship and acoustic axis consistency between the two.

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