A small-aperture target detection array based on a combination of marker vectors and a control method

Abstract

The application discloses a kind of based on scalar vector combination Small aperture target detection array and control method, the array includes shell, transceiver common vector transducer, scalar hydrophone group, fixed mounting accessory, signal acquisition system, target detection system and display control system, transceiver common vector transducer is set in the coordinate origin position of linear array, corresponding installation in the bow of underwater unmanned platform, the structure of transceiver common vector transducer is spliced inlay circular ring type vector transducer.The application can improve the detection performance and anti-interference ability in underwater complex environment.The application can be widely applied to underwater detection technical field as a kind of based on scalar vector combination Small aperture target detection array and control method.

Description

Technical Field

[0001] This invention relates to the field of underwater detection technology, and in particular to a small-aperture target detection array and control method based on a combination of target vectors. Background Technology

[0002] The underwater environment is complex and variable, and sound propagation is affected by hydrological conditions, seabed topography, and ocean background noise, making it difficult for traditional methods to effectively detect and track targets under low signal-to-noise ratio conditions. Therefore, improving underwater target detection capabilities is of great significance for marine resource development, ensuring maritime navigation safety, and advancing underwater scientific research. High-performance underwater target detection systems can detect targets in complex environments, providing key technical support for marine target detection and underwater resource exploration.

[0003] The rapid development of small underwater unmanned mobile platforms has provided strong technical support for underwater target detection, becoming an important carrier for future underwater detection systems. Compared to large manned platforms, underwater unmanned mobile platforms possess characteristics such as autonomous navigation, high maneuverability, and low self-noise, enabling them to perform long-duration target detection missions in complex marine environments. The flexible deployment methods of underwater unmanned mobile platforms make them adaptable to various underwater operational scenarios, such as target detection, environmental monitoring, and resource exploration. Furthermore, multiple underwater unmanned mobile platforms can be networked to jointly detect and track targets, improving the efficiency of target detection and tracking. With the integrated development of artificial intelligence, advanced sensors, and autonomous control technologies, underwater unmanned platforms will further enhance their ability to acquire marine environmental and target information, providing more efficient and intelligent solutions for future underwater detection missions.

[0004] The rise of small underwater unmanned mobile platforms has placed higher demands on underwater acoustic detection equipment, requiring high-performance detection tasks within limited size and power consumption. First, sensors must be miniaturized, highly sensitive, and low-power to adapt to the platform's space, power, and energy requirements. Second, the limited space of small platforms restricts the aperture of sonar arrays, limiting their ability to detect low-frequency targets. Furthermore, functional multiplexing has become a key research direction for underwater small-platform detection systems. Due to space, power, and energy constraints, a single sensor must be able to perform multiple tasks simultaneously; for example, a vector hydrophone can simultaneously receive sound pressure and particle velocity information, with the velocity signal possessing a certain spatial directivity gain. Finally, a combined active and passive signal processing method can enhance the system's target detection capability in environments with lower signal-to-noise ratios.

[0005] Conventional detection arrays mounted on small underwater unmanned platforms are primarily towed wire arrays, with array elements mainly composed of scalar hydrophones, towed and positioned at the stern of the platform for detection. However, towed wire arrays are susceptible to noise from the platform's propellers. Furthermore, they are prone to element displacement due to ocean currents during operation, requiring calibration techniques. Vector arrays, composed of vector hydrophones, suffer from larger apertures due to the limitations of vector hydrophone size. Current research focuses on bottom-mounted, vertical arrays, which offer far less flexibility than arrays mounted on mobile underwater platforms. Moreover, both towed and vector arrays operate primarily passively, leaving room for improvement in detection performance. Summary of the Invention

[0006] To address the aforementioned technical problems, the present invention aims to provide a small-aperture target detection array and control method based on vector combination, which can improve detection performance and anti-interference capability in complex underwater environments.

[0007] The first technical solution adopted in this invention is: a small-aperture target detection array based on scalar vector combination, comprising a housing, a transceiver vector transducer, a scalar hydrophone group, fixed mounting accessories, a signal acquisition system, a target detection system, and a display and control system. The transceiver vector transducer and the scalar hydrophone group are fixedly installed inside the housing and arranged along the same axis to form a linear array structure. The signal output terminals of the transceiver vector transducer and the scalar hydrophone group are both connected to the signal input terminal of the signal acquisition system. The digital signal output terminal of the signal acquisition system is connected to the input terminal of the target detection system. The detection result output terminal of the target detection system is connected to the display input terminal of the display and control system. The control output terminal of the display and control system is connected to the control terminal of the transceiver vector transducer and the control terminal of the signal acquisition system, respectively. The fixed mounting accessories are disposed on the outside of the housing, wherein: The transceiver vector transducer is used to passively receive vector signals of the underwater acoustic field, and to transmit detection sound waves and receive target reflected echo signals in active detection mode. The scalar hydrophone array is used to passively receive underwater sound pressure signals, and to receive sound pressure signals of target reflected echoes in active detection mode. The fixed mounting accessories are used to fix the overall detection array to the underwater unmanned platform, reducing the interference of platform self-noise and flow noise on array detection; The signal acquisition system is used to filter, amplify, and perform analog-to-digital conversion on the received analog electrical signals, and output standardized synchronous digital signals. The target detection system is used to perform beamforming and fusion processing on vector signals and underwater acoustic pressure signals to complete target detection and azimuth estimation and output detection results. The display and control system is used to configure system initialization parameters, switch between active and passive working modes, visualize detection results, and monitor system operation status.

[0008] Furthermore, the scalar hydrophone group specifically includes several scalar hydrophones. The transceiver vector transducer is located at the origin of the linear array and is installed at the bow of the underwater unmanned platform. The several scalar hydrophones are arranged sequentially along the axis of the platform's navigation direction on the back of the platform. The center-to-center distance between the transceiver vector transducer and adjacent scalar hydrophones, as well as the center-to-center distance between two adjacent scalar hydrophones, is half a wavelength. The operating frequency range of the transceiver vector transducer and the several scalar hydrophones is consistent.

[0009] Furthermore, the transceiver shared vector transducer is a modular circular vector transducer, which is composed of several long strip piezoelectric ceramic strips evenly spliced ​​and pasted along the circumference. The piezoelectric ceramic strips on the circumference are divided into four groups, each group containing several identical numbers of piezoelectric ceramic strips connected in parallel, and each group outputs one electrode signal.

[0010] Furthermore, the natural directivity of the linear array structure exhibits a unipolar characteristic, which is used to distinguish between port and starboard incident signals symmetrical about the axis of the linear array structure, and to suppress symmetrical incident signals from non-target sides.

[0011] Furthermore, the signal acquisition system specifically includes a pre-filtering and amplification unit, an analog-to-digital conversion unit, and a data verification unit, wherein: The pre-filtering and amplification unit is used to perform bandpass filtering and gain amplification on the analog electrical signal, filter out noise outside the operating frequency band, and obtain the amplified analog signal. The analog-to-digital conversion unit is used to convert the amplified analog signal into a digital signal, forming synchronous data between the vector channel and the scalar channel, and obtaining a standardized digital signal that has passed verification. The data verification unit is used to remove abnormal data and transmit the verified standardized digital signals to the target detection system.

[0012] Furthermore, the target detection system specifically includes a beamforming processing unit, a target vector signal fusion processing unit, and an azimuth estimation processing unit, wherein: The beamforming processing unit is used to perform beam scanning by combining the directional characteristics of the vector transducer, suppress irrelevant directional noise, and preliminarily determine the target azimuth range. The scalar-vector signal fusion processing unit is used to fuse the vibration velocity and sound pressure data of the vector channel with the sound pressure data of the scalar channel to obtain fused data. The orientation estimation processing unit is used to calculate the specific orientation parameters of the target based on the fused data according to the target orientation range, and output the target detection results.

[0013] Furthermore, the display and control system supports switching between passive detection mode and active detection mode, wherein: In the passive detection mode, the display and control system controls the transceiver vector transducer to only enable the signal receiving function, and the scalar hydrophone group and the vector transducer synchronously and passively receive the underwater acoustic signal. In the active detection mode, the display and control system controls the transceiver vector transducer to simultaneously activate the acoustic wave transmission and signal reception functions, transmit detection acoustic waves in a preset frequency band, and the scalar hydrophone group and the vector transducer synchronously receive the target reflected echo.

[0014] The second technical solution adopted in this invention is: a control method for a small-aperture target detection array based on target vector combination, comprising: Obtain the system initialization command, complete the array installation status verification, array element working parameter configuration, acquisition parameter configuration, and detection working mode selection to obtain the initialized detection system; Based on the initialized detection system, the detection working mode is selected, and the transceiver vector transducer and scalar hydrophone group are controlled to synchronously acquire underwater acoustic signals and convert the underwater acoustic signals into analog electrical signals. The analog electrical signal is sequentially subjected to bandpass filtering, gain amplification, and analog-to-digital conversion to obtain a standardized synchronous digital signal for the vector channel and scalar channel. Beamforming scanning and scalar signal fusion processing are performed on the standardized vector channel and scalar channel synchronous digital signals to complete target detection and azimuth estimation, and output the target detection results. The system visualizes the target detection results, monitors the operating status of each module in real time, and adjusts the system operating parameters based on the detection feedback to form a control closed loop.

[0015] The beneficial effects of the array and control method of this invention are as follows: This invention, through the rational arrangement of vector transducers and scalar hydrophones, adapts to the spatial characteristics of small underwater platforms, and the array is fixed at the bow of the platform, effectively reducing platform self-noise and flow noise interference. Furthermore, by using vector transducers with a mosaic ring structure, sound field vector information can be acquired. Combined with the sound pressure information from the scalar hydrophones, the array's directivity gain is improved with a small number of array elements, solving the problem of insufficient spatial gain of a single scalar array. Additionally, the vector transducers also have active transmission capabilities, enabling coordinated active and passive detection, compensating for the shortcomings of single passive detection, improving detection performance and anti-interference capabilities in complex environments. The introduction of vector transducers also solves the port- starboard ambiguity problem inherent in linear arrays. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the installation of a small-aperture target detection array based on a target vector combination according to the present invention; Figure 2 This is a flowchart of a control method for a small-aperture target detection array based on a combination of standard vectors, according to the present invention. Figure 3 This is a schematic diagram of the element distribution of a small-aperture vector array provided in a specific embodiment of the present invention; Figure 4 This is a schematic diagram of the transceiver vector transducer of the inlaid circular ring type used in the small aperture vector array provided in a specific embodiment of the present invention; Figure 5 This is a schematic diagram of the simulation model of each element of the small aperture vector array provided in a specific embodiment of the present invention; Figure 6 This is a front view schematic diagram of the simulation model of each element of the small aperture vector array provided in a specific embodiment of the present invention; Figure 7 This is a top view schematic diagram of the simulation model of each element of the small aperture vector array provided in a specific embodiment of the present invention; Figure 8 This is a left-side view of the simulation model of each element of the small-aperture vector array provided in a specific embodiment of the present invention; Figure 9 This is a right-side schematic diagram of the simulation model of each element of the small aperture vector array provided in a specific embodiment of the present invention; Figure 10 This is a schematic diagram of the detection system framework of the small aperture vector array provided in a specific embodiment of the present invention; Figure 11 This is a schematic diagram of the workflow of the small aperture vector array in active and passive modes provided in a specific embodiment of the present invention; Figure 12 This is a schematic diagram of a small-aperture vector array receiving signal model provided in a specific embodiment of the present invention; Figure 13 This is a schematic diagram of the natural directional distribution of the small aperture vector matrix in the positive horizontal direction, provided in a specific embodiment of the present invention; Figure 14 This is a schematic diagram of the natural directional distribution of the small aperture vector array in the end-fire direction provided in a specific embodiment of the present invention; Figure 15 This is a schematic diagram of the differential pressure vector hydrophone array in an alternative solution provided in a specific embodiment of the present invention. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are only for ease of explanation and do not limit the order of the steps. The execution order of each step in the embodiments can be adapted according to the understanding of those skilled in the art.

[0018] First, it should be noted that the existing technology has the following drawbacks: 1) Due to space limitations on underwater unmanned mobile platforms, existing detection arrays mounted on small underwater platforms are mostly towed wire arrays, installed at the stern of the platform to detect underwater targets. However, towed wire arrays are easily affected by the platform's self-noise and current noise, limiting their accuracy and capability in detecting targets. Furthermore, to improve detection capabilities, towed wire arrays often have dozens or even hundreds of elements, resulting in high system power consumption that may exceed the energy carrying capacity of small underwater unmanned platforms, making it difficult to ensure long-term system operation.

[0019] 2) Existing detection arrays mounted on underwater unmanned mobile platforms primarily consist of scalar hydrophones. Their core function is limited to acquiring sound pressure information of underwater acoustic signals, failing to obtain vector information such as vibration velocity. However, during the propagation of underwater acoustic signals, sound pressure and vibration velocity are interrelated, jointly reflecting key parameters such as the target's azimuth, distance, and motion state. Under the same array element count and aperture, the spatial gain obtained by a single scalar hydrophone array is often less than that of an array composed of vector hydrophones. Furthermore, an array composed entirely of vector hydrophones occupies significantly more space than an array composed of scalar hydrophones, and the limited space of small underwater platforms further restricts the development of vector arrays composed entirely of vector hydrophones. For these reasons, detection sonar arrays mounted on small underwater platforms need to make reasonable use of the platform's spatial characteristics and rationally design the layout of scalar hydrophones and vector transducers to ensure high spatial gain while minimizing the array's space footprint.

[0020] 3) Existing detection arrays mounted on underwater unmanned mobile platforms mostly operate in a single passive detection mode, lacking the combined detection capability of active transmission and passive reception. Furthermore, arrays mounted on underwater mobile platforms in only passive detection mode are more susceptible to the platform's self-noise. These factors reduce the array's anti-interference capability and decrease its detection reliability in complex underwater environments. The core logic of passive detection mode is to passively receive the acoustic signals radiated or reflected by the underwater target itself using hydrophone array elements, without actively transmitting acoustic signals, offering the advantage of strong concealment. However, this mode has significant limitations. First, passive detection mode relies on the target's own acoustic radiation. For underwater targets with strong acoustic concealment, their self-radiated acoustic signals are extremely weak, making it difficult for passive detection arrays to capture their signals, potentially leading to detection failure. Second, in complex underwater environments, there is a large amount of environmental noise and interference signals, and the self-noise of the mobile platform also affects the array. This noise and interference can superimpose with the target signal, making it difficult for the passive detection array to distinguish between the target and noise, further reducing detection accuracy and reliability. In contrast, active detection modes actively emit acoustic signals and utilize the echo signals reflected from the target to achieve target detection, thus possessing a certain degree of anti-interference capability. Therefore, existing arrays with only passive detection modes have significant performance shortcomings in scenarios such as target detection under complex underwater interference environments and low signal-to-noise ratio conditions, and cannot meet the diverse and high-precision detection requirements of underwater unmanned mobile platforms.

[0021] 4) Existing towed arrays composed of scalar hydrophones struggle to resolve the port-side ambiguity inherent in standard linear arrays. This port-side ambiguity is a typical technical bottleneck for scalar hydrophone linear arrays. The root cause is that scalar hydrophones can only collect underwater sound pressure information and cannot capture the vector characteristics of the sound field, thus failing to distinguish the port or starboard side of the incident signal. When an underwater target is located symmetrically on either the port or starboard side of the platform, the array cannot determine its exact location using conventional array signal processing methods. This leads to deviations in target bearing determination, and in severe cases, can cause incorrect target localization, misleading subsequent detection decisions.

[0022] Based on this, this invention proposes an active and passive target detection method based on scalar vector arrays, providing a new technical solution to overcome the performance bottleneck of miniaturized underwater acoustic detection systems. Compared to traditional towed wire arrays, single-vector hydrophones, or vector array detection methods, scalar vector arrays integrate sound pressure and particle velocity information. In the combined active and passive signal processing, they fully utilize the directivity of the vector channel and the signal strength information of the scalar channel, enabling target detection even in weak signals. Scalar vector arrays can provide a new technical solution for low-frequency target detection in small-aperture sonar, promote the development of underwater acoustic target detection technology on small platforms, provide technical support for future small-platform underwater detection systems, promote the development of efficient and intelligent underwater target detection technology, and provide more efficient and accurate technical support for fields such as marine exploration and environmental monitoring.

[0023] Therefore, the objective of this invention is: 1) To address the issues of platform self-noise interference, high power consumption due to multiple array elements, and insufficient battery life of the drag-and-drop array, the array layout is optimized to reduce interference and power consumption, and to adapt to the space and energy carrying capacity of the AUV platform.

[0024] 2) To address the issues of low spatial gain in scalar hydrophone arrays and large space requirements in pure vector hydrophone arrays, a reasonable combination of scalar hydrophones and vector transducers can improve spatial gain while saving space.

[0025] 3) To address the port and starboard ambiguity issue of the standard linear array, adding a vector transducer to the standard vector array can effectively solve the port and starboard ambiguity problem.

[0026] 4) To address the issues of poor anti-interference and difficulty in detecting targets in a single passive detection mode, a vector transducer unit for both transmission and reception is introduced to construct a detection mechanism that integrates active transmission and passive reception. This improves detection accuracy, anti-interference capability, and reliability. It can perform passive target detection to enhance stealth and use active mode to enhance detection capability, thus meeting the diverse and high-precision detection needs of small underwater unmanned mobile platforms.

[0027] Reference Figure 1This invention provides a small-aperture target detection array based on scalar vector combination, comprising a housing, a transceiver vector transducer, a scalar hydrophone group, fixed mounting accessories, a signal acquisition system, a target detection system, and a display and control system. The transceiver vector transducer and the scalar hydrophone group are fixedly installed inside the housing and arranged along the same axis to form a linear array structure. The signal output terminals of the transceiver vector transducer and the scalar hydrophone group are both connected to the signal input terminal of the signal acquisition system. The digital signal output terminal of the signal acquisition system is connected to the input terminal of the target detection system. The detection result output terminal of the target detection system is connected to the display input terminal of the display and control system. The control output terminal of the display and control system is connected to the control terminal of the transceiver vector transducer and the control terminal of the signal acquisition system, respectively. The fixed mounting accessories are disposed on the outside of the housing. This embodiment designs a small-aperture target detection array based on a combination of vector transducers and scalar hydrophones. The rational layout of the vector sensors makes the array element distribution more reasonable, suitable for the detection needs of underwater unmanned mobile platforms. The spatial gain of the array is improved by utilizing the sound field vector information of the vector transducers. Simultaneously, the vector transducers have the ability to actively transmit sound waves, enabling the array to switch to active detection mode, achieving coordinated active and passive detection. This provides a detection sonar array technology suitable for mounting on small underwater unmanned mobile platforms. Through the rational layout of shared vector transducers and scalar hydrophones, and by utilizing the spatial gain of the vector transducers and the advantages of active sound wave transmission, a high spatial gain target detection system is provided for the platform.

[0028] The housing serves as the supporting foundation for the entire detection array. Its core function is to provide sealing, protection, and fixed support for the core components such as the vector array elements and signal processing system inside, preventing damage to the components from underwater high pressure, water flow impact, and impurities. At the same time, it ensures the stable installation posture of each detection component, providing a basic guarantee for the accurate reception and transmission of subsequent acoustic signals. It is directly connected to the vector transducer and scalar hydrophone, and the two are fixed in the preset position through the built-in installation structure to ensure that the relative position of the two meets the array requirements, thus ensuring the synchronization and accuracy of acoustic signal reception.

[0029] The transceiver vector transducer is used to passively receive vector signals of the underwater acoustic field, and to transmit detection sound waves and receive target reflected echo signals in active detection mode. Specifically, the transceiver shared vector transducer has a structure of a mosaic circular vector transducer, which is composed of several long strip piezoelectric ceramic strips evenly mosaicked and pasted along the circumference. The piezoelectric ceramic strips on the circumference are divided into four groups, each group containing several identical numbers of piezoelectric ceramic strips connected in parallel, and each group outputs one electrode signal.

[0030] In this embodiment, a shared vector transducer serves as the core active and passive detection component of the array. This vector transducer has the dual function of actively emitting sound waves and passively receiving sound field vector signals. Its high directivity effectively focuses the detection direction, reducing noise and interference. Simultaneously, its active transmission function enables the array to operate in active detection mode, providing a signal source for target detection. Together with scalar hydrophones, it forms the core detection array. The vector transducer provides vector information and active detection capability, while the scalar hydrophones provide sound pressure information. Their collaborative operation compensates for the limitations of single-sensor detection, improving the array's spatial gain and detection accuracy. Furthermore, as the central unit of the array, the vector transducer's installation position determines the overall array layout. Five scalar hydrophones are arranged along the platform's navigation direction, forming a linear array structure, ensuring the array's directivity meets design requirements.

[0031] The scalar hydrophone array is used to passively receive underwater sound pressure signals, and to receive sound pressure signals of target reflected echoes in active detection mode. Specifically, the scalar hydrophone group includes several scalar hydrophones. The transceiver vector transducer is located at the origin of the linear array and is installed at the bow of the underwater unmanned platform. The several scalar hydrophones are arranged sequentially along the axis of the platform's navigation direction on the back of the platform. The center-to-center distance between the transceiver vector transducer and adjacent scalar hydrophones, as well as the center-to-center distance between two adjacent scalar hydrophones, is half a wavelength. The operating frequency range of the transceiver vector transducer and the several scalar hydrophones is the same.

[0032] In this embodiment, the scalar hydrophone serves as the core component for passive detection. Its primary function is to passively receive sound pressure signals in the water, converting them into electrical signals to provide sound pressure data for subsequent signal processing. Five scalar hydrophones can be individually combined into a standard linear array for basic passive target detection, or combined with a vector transducer to form a scalar-vector array. The vector information from the vector transducer supplements the scalar data, further enhancing the array's spatial directivity gain and addressing the issues of low spatial gain and port-side ambiguity in a single scalar linear array. The correlation between the scalar hydrophone and the vector transducer lies in their consistent operating frequencies (1000 Hz~1500 Hz) and sound pressure sensitivity, ensuring accurate fusion of the received acoustic signals through subsequent signal processing. Furthermore, the fixed half-wavelength array arrangement guarantees signal transmission delay stability, providing a basis for delay difference compensation.

[0033] Furthermore, the natural directivity of the linear array structure exhibits a unipolar characteristic, which is used to distinguish between port and starboard incident signals symmetrical about the axis of the linear array structure, and to suppress symmetrical incident signals from non-target sides.

[0034] The fixed mounting accessories are used to fix the overall detection array to the underwater unmanned platform, reducing the interference of platform self-noise and flow noise on array detection; In this embodiment, the core function of the fixed mounting accessories is to fix the entire vector detection array on a small underwater unmanned platform. At the same time, through reasonable installation design, it minimizes the interference of platform self-noise and current noise on the array detection components. It is directly connected to the shell and platform, with one end connected to the shell and the other end fixed in a preset position on the platform, ensuring that the array does not shift or shake during underwater navigation, ensuring the stable installation posture of each detection component, thereby ensuring the accuracy of acoustic signal reception and avoiding detection errors caused by loose installation.

[0035] The signal acquisition system is used to filter, amplify, and perform analog-to-digital conversion on the received analog electrical signals, and output standardized synchronous digital signals. Specifically, the signal acquisition system includes a pre-filtering and amplification unit, an analog-to-digital conversion unit, and a data verification unit. The pre-filtering and amplification unit performs bandpass filtering and gain amplification on the analog electrical signal to filter out noise outside the operating frequency band and obtain an amplified analog signal. The analog-to-digital conversion unit converts the amplified analog signal into a digital signal to form synchronous data for the vector channel and the scalar channel, obtaining a standardized digital signal that has passed verification. The data verification unit removes abnormal data and transmits the standardized digital signal that has passed verification to the target detection system.

[0036] In this embodiment, the core function of the signal acquisition system is to receive the electrical signals output by the vector transducer and the scalar hydrophone. It includes a pre-filtering and amplification system and a signal acquisition system to acquire and preprocess the signals (such as filtering and amplification). It is directly associated with the vector transducer and the scalar hydrophone. Through the processing of the signal acquisition system, the detected acoustic signals are transmitted to the post-processing unit.

[0037] The target detection system is used to perform beamforming and fusion processing on vector signals and underwater acoustic pressure signals to complete target detection and azimuth estimation and output detection results. Specifically, the target detection system includes a beamforming processing unit, a scalar vector signal fusion processing unit, and a azimuth estimation processing unit. The beamforming processing unit performs beam scanning by combining the directional characteristics of the vector transducer, suppressing irrelevant directional noise, and initially determining the target's azimuth range. The scalar vector signal fusion processing unit fuses the vibration velocity and sound pressure data of the vector channel with the sound pressure data of the scalar channel to obtain fused data. The azimuth estimation processing unit calculates the specific azimuth parameters of the target based on the fused data according to the target's azimuth range and outputs the target detection result.

[0038] In this embodiment, the core function of the target detection system is to use a built-in algorithm to process the signals received by the signal acquisition system in a coordinated manner with the vector transducer and scalar hydrophone, thereby achieving target detection and azimuth estimation, and finally outputting the target detection results.

[0039] The display and control system is used to configure system initialization parameters, switch between active and passive working modes, visualize detection results, and monitor system operation status.

[0040] Specifically, the display and control system supports switching between passive and active detection modes. In passive detection mode, the display and control system controls the transceiver vector transducer to only enable signal reception, and the scalar hydrophone group and the vector transducer synchronously and passively receive underwater acoustic signals. In active detection mode, the display and control system controls the transceiver vector transducer to simultaneously enable acoustic wave transmission and signal reception, transmit detection acoustic waves in a preset frequency band, and the scalar hydrophone group and the vector transducer synchronously receive the target reflected echo.

[0041] In this embodiment, the core function of the display and control system is to control the entire vector array (controlling the active transmission frequency and transmission time of the vector transducer, and controlling the acquisition parameters of the signal acquisition system, etc.), and to realize signal transmission and visualization (transmitting the signal processed by the signal acquisition system to the main control unit of the platform, or transmitting the control commands of the main control unit to each component, and simultaneously visualizing the detection data and target information). It is directly associated with the vector transducer and the signal acquisition system to ensure that each component works collaboratively, realizes the switching between active and passive collaborative detection modes, and ensures that the working parameters of each component meet the design requirements, providing operators with intuitive detection feedback and achieving accurate detection and real-time monitoring.

[0042] In summary, the scalar vector detection array can be divided into two parts, consisting of one transmit-receive vector transducer located at the center of the coordinate origin and five scalar hydrophones. The vector transducer and scalar hydrophones are arranged in a linear array along the bow (positive X-axis direction), with a center-to-center spacing of 0.5 m (half-wavelength array). The operating frequencies of the vector transducer and scalar hydrophones are both between 1000 Hz and 1500 Hz.

[0043] The shared transceiver vector transducer is configured as a mosaic circular vector transducer, which also has the function of actively transmitting vector signals, providing the detection system with a combination of active and passive detection benefits. The scalar hydrophones are mounted on the back of the platform. The five scalar hydrophones can be individually combined into a standard linear array for passive target detection, or they can be combined with the vector transducer to form a scalar vector array with higher spatial directivity gain for target detection.

[0044] The vector transducer is a cylindrical transducer made up of 48 piezoelectric ceramic strips. The center of the vector transducer is located at the origin of the coordinate system. The centers of the five scalar hydrophones are located on the same axis (the direction of platform operation) as the center of the vector transducer. The sound pressure sensitivity of the vector transducer is the same as that of the five scalar hydrophones.

[0045] The vector units of the scalar array are placed at the bow of the platform, and the scalar units are placed at the back of the platform. The array is fixed to the platform using matching fasteners to minimize the interference of the platform's self-noise and flow noise on the array.

[0046] The aforementioned vector array incorporates the directional advantages of vector transducers, giving the array a unipolar directional characteristic, which can effectively solve the port and starboard ambiguity problem present in conventional linear arrays.

[0047] Therefore, vector transducers and scalar hydrophones collect target reflected echoes, the signal acquisition system provides pre-processed digital signals, the display and control system provides control commands and display feedback, and the fixed installation accessories and housing ensure stability during signal acquisition. The housing, vector transducers, and scalar hydrophones, as the core detection and support components of the array, work together to achieve the function of receiving underwater acoustic signals. The housing provides a stable installation and protection environment for the scalar vector array. The vector transducers are responsible for actively emitting sound waves and receiving vector acoustic signals, while the scalar hydrophones are responsible for passively receiving scalar sound pressure signals. These two components work together to provide the basic acoustic signal source for the entire detection system. The target detection system integrates the outputs of all components, achieving detection functionality through algorithm fusion, and simultaneously feeds the detection results back to the display and control system, forming a complete closed loop of "control-detection-acquisition-processing-control-display," ensuring that the entire detection array can complete the underwater target detection task.

[0048] This embodiment utilizes a combined array design of scalar hydrophones and vector transducers to achieve a smaller detection array aperture, facilitating its placement on a small underwater platform. Furthermore, the shared transmit / receive vector transducer enables the detection array to possess active detection capabilities, enhancing its detection performance. The scalar vector array design achieves higher array directivity gain with fewer array elements. This design also ensures that the array elements are fixed at the bow of the platform, minimizing the impact of platform self-noise and current noise. The natural directivity of the scalar vector array exhibits unipolar directivity characteristics, effectively resolving the port and starboard ambiguity issues present in standard linear arrays.

[0049] Therefore, the structure of the embodiments of the present invention has the following advantages compared with the prior art: 1) By rationally arranging one vector transducer and five scalar hydrophones, the spatial characteristics of the small underwater platform are adapted, and the array is fixed at the bow of the platform, which effectively reduces the interference of platform self-noise and flow noise.

[0050] 2) By using a vector transducer with a mosaic ring structure, sound field vector information can be obtained. Combined with the sound pressure information of a scalar hydrophone, the array directivity gain can be improved with a small number of array elements, thus solving the problem of insufficient spatial gain of a single scalar array.

[0051] 3) The vector transducer also has an active transmission function, realizing active and passive coordinated detection, making up for the shortcomings of single passive detection, and improving the detection performance and anti-interference ability in complex environments.

[0052] 4) The number of array elements is relatively small, which is suitable for the spatial characteristics of small underwater mobile platforms. Reducing the number of array elements reduces power consumption, ensures long-term platform endurance, and fully meets the high-precision detection requirements of small underwater platforms.

[0053] 5) By utilizing the directivity of vector transducers, the natural directivity of the array is made to have a unipolar characteristic, which can effectively solve the port and starboard ambiguity problem existing in standard linear arrays.

[0054] In summary, the steps of the embodiments of the present invention have the following advantages compared with the prior art: 1) Compared with existing towed arrays, the embodiments of the present invention can be fixedly installed on an underwater unmanned platform, reducing the impact of platform self-noise and flow noise on the array; 2) By using a vector transducer that is shared for both transmission and reception, this embodiment of the invention can achieve target detection in both active and passive modes, which improves the overall detection capability of the system compared to the passive mode of a towed array. 3) Based on the directional advantage of vector transducers, with the same number of array elements, the embodiment of the present invention can obtain about 2 dB more spatial directional gain than the traditional standard linear array. Under the condition of the same spatial gain, the present invention requires 3 fewer array elements than the traditional standard linear array. 4) Based on the directional advantage of vector transducers, the array in this embodiment of the invention has unipolar directionality, which can effectively solve the port and starboard ambiguity problem of towed arrays.

[0055] Reference Figure 2 A control method for a small-aperture target detection array based on target vector combination includes the following steps: S100: Obtain system initialization instructions, complete array installation status verification, array element working parameter configuration, acquisition parameter configuration, and detection working mode selection to obtain the initialized detection system; In this embodiment, system initialization and parameter configuration are first performed (based on the display and control system, linking the vector transducer, scalar hydrophone, signal acquisition system, and detection system), specifically including: 1) The operator issues an initialization command through the display and control system to first obtain the status data of the fixed installation accessories (including attitude angle, connection stability with the platform, etc.) to confirm that the array installation is not loose and the attitude meets the preset navigation direction (positive X-axis direction) array requirements. If an installation abnormality is detected (such as looseness or attitude deviation), the display and control system issues an alarm signal to prompt the operator to adjust the fixed installation accessories until the status data meets the standard, to ensure the stability of the array attitude during subsequent detection and to avoid installation errors affecting the signal acquisition accuracy. 2) After confirming that the installation status is correct, the display and control system sends parameter configuration instructions to the vector transducer and the scalar hydrophone, sets the operating frequency of both, calibrates the sound pressure sensitivity of both, and ensures that the sound pressure sensitivity of the two parts is consistent; at the same time, the operating mode of the vector transducer (active detection mode or passive detection mode) is configured. In passive mode, only the receiving function is enabled, while in active mode, both the transmitting and receiving functions are enabled. 3) The display and control system sends acquisition parameter instructions to the signal acquisition system to set parameters such as signal acquisition frequency, filtering threshold, and amplification factor, ensuring that the acquisition system can accurately receive the electrical signals output by the vector transducer and scalar hydrophone, while filtering out noise in the underwater environment to provide high-quality raw data for subsequent signal processing.

[0056] S200: Based on the initialized detection system, select the detection working mode, control the transceiver vector transducer and scalar hydrophone group to synchronously collect underwater acoustic signals, and convert the underwater acoustic signals into analog electrical signals. In this embodiment, signal acquisition is further performed (based on a standard vector array, outputting data to a signal acquisition system), specifically including: 1) In passive detection mode: the vector transducer passively receives the sound field vector data (including sound pressure and vibration velocity information) in the water, and the scalar hydrophones (five scalar units) synchronously and passively receive the scalar sound pressure data in the water. Both convert the received sound signals into analog electrical signals and output them to the signal acquisition system in real time. Among them, the five scalar hydrophones synchronously acquire data to ensure the signal synchronization of the linear array, while the vector transducer uses the origin of the coordinate system as a reference to acquire vector signals, providing a basis for subsequent direction positioning. 2) In active detection mode: The display and control system controls the vector transducer to emit a broadband detection signal at a preset frequency (1000 Hz~1500 Hz). When the sound wave propagates in the water and encounters the target, it reflects the signal. The vector transducer of the scalar vector array and five scalar hydrophones synchronously receive the reflected sound pressure signal. Both convert the reflected signal into an analog electrical signal and output it to the signal acquisition system in real time. At the same time, the vector transducer continuously collects feedback data of its own emitted signal for subsequent calibration of the emission accuracy.

[0057] S300 sequentially performs bandpass filtering, gain amplification, and analog-to-digital conversion on the analog electrical signal to obtain standardized vector and scalar synchronous digital signals; In this embodiment, signal preprocessing is then performed (based on the signal acquisition system, receiving preceding data, processing it, and outputting it to the target detection system), specifically including: 1) After receiving the analog electrical signals output by the vector transducer and scalar hydrophone, the signal acquisition system first filters the signals to remove noise (such as platform noise and water flow noise) with frequencies exceeding 1000 Hz~1500 Hz, while retaining the effective signals related to the target. 2) The preamplifier system amplifies the filtered signal, increasing the weak electrical signal to a preset amplitude to ensure that the signal strength meets the requirements of subsequent algorithm processing, while avoiding signal distortion. 3) Perform analog-to-digital conversion on the amplified analog signal to convert it into a digital signal, forming standardized vector-scalar synchronization data; 4) The signal acquisition system performs preliminary verification on the synchronized digital signal, removes abnormal data (such as sudden changes in signal amplitude, missing data, etc.), and transmits the verified standardized data to the target detection system in real time as input data for target processing.

[0058] S400 performs beamforming scanning and scalar signal fusion processing on the standardized vector channel and scalar channel synchronous digital signals to complete target detection and azimuth estimation, and outputs the target detection results; In this embodiment, target recognition and localization processing is further performed (based on the target detection system, receiving preceding data, processing it, and outputting it to the display and control system), specifically including: 1) After receiving the vector-scalar data transmitted by the signal acquisition system, the target detection system first performs beam scanning on the data by using a beamforming algorithm combined with the directional characteristics of the vector transducer, suppressing noise in irrelevant directions, enhancing the signal strength in the target direction, and initially determining the approximate location of the target. 2) A signal fusion algorithm is used to fuse the vibration velocity and sound pressure vector data collected by the vector transducer with the scalar sound pressure data collected by the scalar hydrophone, so as to make up for the limitations of single data types, improve the signal-to-noise ratio of the input signal, and detect the target signal. 3) The target detection system verifies the calculated target parameters. After confirming that the data is correct, it transmits the target detection results (including whether the target exists and the target's specific location parameters) to the display and control system in real time.

[0059] The S500 provides a visual representation of the target detection results, monitors the operating status of each module in real time, and adjusts the system's operating parameters based on the detection feedback to form a control closed loop.

[0060] In this embodiment, the final step is result display and system control (based on a display and control system, receiving preceding data and linking various modules to complete closed-loop control), specifically including: 1) After receiving the detection results transmitted by the target detection system, the display and control system visualizes them (such as whether a target exists, the target's line spectrum, the target's azimuth history, etc.), providing operators with intuitive detection feedback and facilitating real-time monitoring of underwater target conditions. 2) Based on the detection results displayed on the display and control system, the operator can adjust the operating parameters of each device through the display and control system: if the target signal is weak, the vector transducer can be controlled to increase the transmission power (active mode); if excessive noise interference is detected, the platform's running speed can be controlled to reduce the impact of platform noise and flow noise. 3) The display and control system continuously receives status data from each module (vector transducer transmit / receive status, scalar hydrophone acquisition status, signal acquisition system operating status, target detection system processing status), monitors the system operation in real time, and immediately issues an alarm signal and stops the operation of the relevant module to prevent the fault from escalating and ensure the stable operation of the system.

[0061] Finally, the embodiments of the present invention will be explained and described with reference to the accompanying drawings, and a method for arranging a small-aperture vector array suitable for underwater small platforms will be proposed, such as... Figure 1 as well as Figure 3 As shown, its basic structure consists of a single, interlocking circular vector transceiver and five scalar hydrophones. The vector transceiver is fixed to the bow of the underwater unmanned platform, with its center located at the origin of the coordinate system. The five scalar hydrophones are mounted on the back of the underwater unmanned platform, and the scalar vector array is arranged in a linear array. The center-to-center spacing of each array element is half a wavelength, the element spacing d is 0.5 m, and the center frequency of the detection system is designed to be 1500 Hz.

[0062] like Figure 4 As shown, the vector transducer used for both transmission and reception is a modular ring structure, with piezoelectric ceramic strips as its basic component. The ring is composed of 48 long, strip-shaped piezoelectric ceramic strips, evenly distributed around its circumference. The entire ring has a diameter of 200 mm, a thickness of 12 mm, and a height of 80 mm. The 48 piezoelectric ceramic strips on the circumference are divided into four equal parts, each consisting of 12 parallel-connected piezoelectric ceramic strips, each outputting a signal from one set of electrodes. The sensitivity of the scalar hydrophone used is consistent with the piezoelectric ceramics of the ring.

[0063] Overall simulation model such as Figure 5As shown, the overall array structure consists of one interlocking circular transceiver vector transducer and five scalar hydrophones. The aperture of the entire array is 2.6 m. The front view, top view, left view, and right view of the array are shown below. Figure 6 , Figure 7 , Figure 8 as well as Figure 9 As shown.

[0064] like Figure 10 As shown, its basic structure includes one transmit / receive vector transducer, five scalar hydrophones, a signal acquisition system, a signal processing system, and a display and control system. The vector transducer and the five scalar hydrophones are array sensors. The signal acquisition system is used to collect and record the target echo signals obtained by each sensor. The signal processing system uses corresponding signal processing methods to detect the target and estimate its azimuth. The display and control system visualizes the target detection information and controls the operation of the entire system.

[0065] As shown in Appendix 11, the various components are controlled by a display and control system. The active and passive detection modes are selected through the display and control system. The data flow and processing of each module form a logical closed loop, namely, "initial configuration of the display and control system - acquisition of raw signals by each element of the target vector array - preprocessing by the signal acquisition system - analysis and processing by the target detection system - display and control by the display and control system - feedback adjustment of each module". The control of each device is based on the output data of the previous module, ensuring the continuity and accuracy of the entire detection process, while clarifying the collaborative working logic of each device.

[0066] Furthermore, the method for calculating the natural directionality of the target vector matrix is ​​analyzed to verify its ability to resolve the port and starboard ambiguity problem: like Figure 12 As shown, this invention proposes an arraying method for a small-aperture target vector array. Its received signal model is assumed to be a far-field plane wave, with the bow direction as the positive direction in polar coordinates. If the target is at an azimuth angle... When signals are received by a small-aperture scalar vector array, a fixed path difference Δ exists between the signals received by adjacent array elements. Since the scalar vector array is evenly spaced, the path difference between a vector transducer and its adjacent scalar hydrophone is also Δ. The path difference is related to the element spacing d and the angle of incidence. Regarding the time delay of received signals between adjacent array elements. Represented as: Among them, the process difference According to the theory of array signals, if a standard linear array is composed entirely of scalar hydrophones, the array manifold of the linear array can be expressed as: in, It is the angular frequency of the signal. The scalar vector array proposed in this invention replaces the scalar hydrophone at the first element position with a vector transducer, thus enabling it to receive signals from three channels: sound pressure and vibration velocity. The vibration velocity channel signal is divided into an X-axis vibration velocity component. and Y-axis velocity components According to the theory of vector transducers, the sound pressure channel signal p and the vibration velocity channel signal... The relationship can be represented as: According to the above formula, the signals in the vibration velocity channel and the sound pressure channel have a sine (cosine) relationship only in terms of amplitude, and this relationship is determined by the angle of incidence. Decision. Based on the above theory, the array manifold of the scalar vector matrix proposed in this invention is: Based on the array manifold of the scalar vector matrix, the formula for calculating the natural orientation of the scalar vector matrix can be obtained: in, This indicates the scanning angle, with a value range of 0~360°.

[0067] like Figure 13 as well as Figure 14 The figures show the natural directivity distribution of the scale vector array when the target is incident on the array in the transverse direction and in the end-fire direction, respectively. Figure 15 It can be seen that when the target echo is incident from the transverse direction (90°) of the array, the scalar vector array allows the signal to pass through completely, while the corresponding 270° direction suppresses the signal to a certain extent, with a suppression effect of about 3dB. In engineering, this can be considered as effective suppression. Therefore, the scalar vector array can effectively solve the port and starboard ambiguity problem. Calculating the directivity gain of the scalar vector array, the directivity gain in the transverse direction is 10.4 dB, and the directivity gain in the end-firing direction is 5.6 dB. In contrast, the directivity gain in the transverse direction of a traditional five-element scalar hydrophone array is only 8.6 dB, and the directivity gain in the end-firing direction is only 4.0 dB. Theoretically, a small-aperture scalar vector array can achieve a spatial directivity gain about 2dB higher than that of a traditional standard linear array. To achieve the same directional gain as the standard vector array, the standard linear array requires at least 8 elements (an 8-element standard linear array has a directional gain of 10.8 dB in the transverse direction and 5.1 dB in the end-fire direction). Adding a vector transducer effectively reduces the number of elements used, lowers the array aperture, and adapts to the spatial characteristics of small underwater platforms. Furthermore, analysis of the natural directional pattern shows that the standard vector array with the vector transducer has a single pole, effectively resolving the port and starboard ambiguity problem of the standard linear array and improving detection accuracy in limited space.

[0068] The content of the above method embodiments is applicable to this system embodiment. The specific functions implemented in this system embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0069] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this is not intended to limit the scope of the embodiments of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the embodiments of the present application.

Claims

1. A small-aperture target detection array based on vector combination, characterized in that, The system includes a housing, a transceiver vector transducer, a scalar hydrophone array, mounting hardware, a signal acquisition system, a target detection system, and a display and control system. The transceiver vector transducer and the scalar hydrophone array are fixedly installed inside the housing and arranged along the same axis to form a linear array structure. The signal output terminals of the transceiver vector transducer and the scalar hydrophone array are both connected to the signal input terminal of the signal acquisition system. The digital signal output terminal of the signal acquisition system is connected to the input terminal of the target detection system. The detection result output terminal of the target detection system is connected to the display input terminal of the display and control system. The control output terminal of the display and control system is connected to the control terminals of the transceiver vector transducer and the signal acquisition system, respectively. The mounting hardware is located on the outside of the housing. The transceiver vector transducer is used to passively receive vector signals of the underwater acoustic field, and to transmit detection sound waves and receive target reflected echo signals in active detection mode. The scalar hydrophone array is used to passively receive underwater sound pressure signals, and to receive sound pressure signals of target reflected echoes in active detection mode. The fixed mounting accessories are used to fix the overall detection array to the underwater unmanned platform, reducing the interference of platform self-noise and flow noise on array detection; The signal acquisition system is used to filter, amplify, and perform analog-to-digital conversion on the received analog electrical signals, and output standardized synchronous digital signals. The target detection system is used to perform beamforming and fusion processing on vector signals and underwater acoustic pressure signals to complete target detection and azimuth estimation and output detection results. The display and control system is used to configure system initialization parameters, switch between active and passive working modes, visualize detection results, and monitor system operation status.

2. The small-aperture target detection array based on vector combination according to claim 1, characterized in that, The scalar hydrophone group specifically includes several scalar hydrophones. The transceiver vector transducer is located at the origin of the linear array and is installed at the bow of the underwater unmanned platform. The several scalar hydrophones are arranged sequentially along the axis of the platform's navigation direction on the back of the platform. The center-to-center distance between the transceiver vector transducer and adjacent scalar hydrophones, as well as the center-to-center distance between two adjacent scalar hydrophones, is half a wavelength. The operating frequency range of the transceiver vector transducer and the several scalar hydrophones is the same.

3. The small-aperture target detection array based on vector combination according to claim 2, characterized in that, The transceiver shared vector transducer is a modular circular vector transducer, which is composed of several long strip piezoelectric ceramic strips evenly spliced ​​and pasted along the circumference. The piezoelectric ceramic strips on the circumference are divided into four groups, each group containing several identical numbers of piezoelectric ceramic strips connected in parallel, and each group outputs one electrode signal.

4. The small-aperture target detection array based on vector combination according to claim 3, characterized in that, The natural directivity of the linear array structure exhibits a unipolar characteristic, which is used to distinguish between port and starboard incident signals symmetrical about the axis of the linear array structure, and to suppress symmetrical incident signals from non-target sides.

5. The small-aperture target detection array based on vector combination according to claim 4, characterized in that, The signal acquisition system specifically includes a pre-filtering and amplification unit, an analog-to-digital conversion unit, and a data verification unit, wherein: The pre-filtering and amplification unit is used to perform bandpass filtering and gain amplification on the analog electrical signal, filter out noise outside the operating frequency band, and obtain the amplified analog signal. The analog-to-digital conversion unit is used to convert the amplified analog signal into a digital signal, forming synchronous data between the vector channel and the scalar channel, and obtaining a standardized digital signal that has passed verification. The data verification unit is used to remove abnormal data and transmit the verified standardized digital signals to the target detection system.

6. The small-aperture target detection array based on target vector combination according to claim 5, characterized in that, The target detection system specifically includes a beamforming processing unit, a target vector signal fusion processing unit, and an azimuth estimation processing unit, wherein: The beamforming processing unit is used to perform beam scanning by combining the directional characteristics of the vector transducer, suppress irrelevant directional noise, and preliminarily determine the target azimuth range. The scalar-vector signal fusion processing unit is used to fuse the vibration velocity and sound pressure data of the vector channel with the sound pressure data of the scalar channel to obtain fused data. The orientation estimation processing unit is used to calculate the specific orientation parameters of the target based on the fused data according to the target orientation range, and output the target detection results.

7. The small-aperture target detection array based on vector combination according to claim 6, characterized in that, The display and control system supports switching between passive detection mode and active detection mode, wherein: In the passive detection mode, the display and control system controls the transceiver vector transducer to only enable the signal receiving function, and the scalar hydrophone group and the vector transducer synchronously and passively receive the underwater acoustic signal. In the active detection mode, the display and control system controls the transceiver vector transducer to simultaneously activate the acoustic wave transmission and signal reception functions, transmit detection acoustic waves in a preset frequency band, and the scalar hydrophone group and the vector transducer synchronously receive the target reflected echo.

8. A control method for a small-aperture target detection array based on vector combination, characterized in that, Includes the following steps: Obtain the system initialization command, complete the array installation status verification, array element working parameter configuration, acquisition parameter configuration, and detection working mode selection to obtain the initialized detection system; Based on the initialized detection system, the detection working mode is selected, and the transceiver vector transducer and scalar hydrophone group are controlled to synchronously acquire underwater acoustic signals and convert the underwater acoustic signals into analog electrical signals. The analog electrical signal is sequentially subjected to bandpass filtering, gain amplification, and analog-to-digital conversion to obtain a standardized synchronous digital signal for the vector channel and scalar channel. Beamforming scanning and scalar signal fusion processing are performed on the standardized vector channel and scalar channel synchronous digital signals to complete target detection and azimuth estimation, and output the target detection results. The system visualizes the target detection results, monitors the operating status of each module in real time, and adjusts the system operating parameters based on the detection feedback to form a control closed loop.

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