17 results about "Hydrophone array" patented technology

The application provides an improved sparse learning out-of-grid direction-of-arrival estimation method based on variational Bayesian. The method is characterized in that: the original data received by a hydrophone array is preprocessed, a real value transformation is used to convert a vectorized covariance matrix signal in a complex number field to a real number field, and the idea of variational sparse Bayesian learning and grid evolution is combined to make the grid evolve from an initial uniform grid to a non-uniform grid adaptively in an iteration process. The evolution process includes grid updating and grid fission. The evolved grid points are gradually close to the real source position through the alternately iterative grid updating process and grid fission process. Compared with the traditional compressed sensing method, the method has higher DOA estimation accuracy, reduces the operation complexity, optimizes the operation efficiency, improves the resolution capacity of the source, and has higher application value in actual engineering, especially in the case of few snapshots and low signal-to-noise ratio.

The application discloses a kind of shore base hydrophone array and underwater unmanned vehicle cooperation's underwater target pure bearing tracking system, belong to underwater passive target detection system field, system is by shore base / sea bed hydrophone static node and AUV dynamic node constitute heterogeneous observation network, each node is configured with hydrophone array, positioning and navigation, time synchronization, underwater acoustic communication, storage and processor hardware, processor runs measurement credibility evaluation module, heterogeneous space-time alignment module (fixed delay cache+pose interpolation+forward-backward smoothing), joint state estimation module (RLS+PF+IMM) and quality perception consistency fusion module;AUV node also runs observation geometry optimization control module, system is unified heterogeneous modeling to static node and dynamic node, in false alarm, delay, out of order, packet loss and pose time-varying actual underwater acoustic engineering conditions realize the high-precision, high robustness continuous passive cooperative tracking of underwater slow target.

The application relates to a bistable SR system and a low signal-to-noise ratio multi-frequency sound signal detection device and method. By introducing an optical fiber device, the closed-loop regulation of the optical fiber grating is utilized to realize the random resonance phenomenon based on the bistability, and the low signal-to-noise ratio signal can be effectively extracted under the strong noise background. Secondly, by introducing a carrier signal, the difference frequency signal is obtained by mixing with the external signal, and the multi-frequency signal sensing is realized under the premise of fixing the detection range of the difference frequency signal. In addition, by introducing the array structure of the optical fiber hydrophone, the spatial gain is formed, and the high-sensitivity detection effect can be realized. Finally, the frequency distribution and the relative signal-to-noise ratio intensity size distribution of the obtained target sound signal can be used as the input of the neural network model, the intelligent identification of the low signal-to-noise ratio target sound target is realized, and the detection and early warning of the underwater target can be maximally realized.

This invention provides a method for locating leaks in water supply networks based on deep learning and a hydrophone array, belonging to the field of water supply network leak detection technology. The method includes: deploying a hydrophone array in the water supply network monitoring area to acquire acoustic signals collected by each hydrophone; preprocessing the acoustic signals; inputting the preprocessed signal data into a pre-trained deep learning feature extraction network to obtain a high-dimensional feature vector reflecting the characteristics of the leaking acoustic waves; calculating a first leak location parameter and a second leak location parameter based on the high-dimensional feature vector, where the first leak location parameter characterizes the spectral characteristics of the leaking sound source, and the second leak location parameter characterizes the spatial attenuation characteristics of the sound wave propagating along the pipeline; and determining the specific location of the leak based on the first and second leak location parameters and the geometric position of the hydrophone array using a location algorithm. This invention combines deep learning for automatic feature extraction with physical parameter correction of the propagation model, improving the accuracy and robustness of leak location.

The utility model discloses a low -noise hydrophone array with easily dismounts support, including support and fixed on the support a plurality of low -noise hydrophone, the support includes mounting panel and hydrophone mounting spare, is equipped with vertical support between hydrophone mounting spare and mounting panel, and hydrophone mounting spare is connected with mounting panel through vertical support, hydrophone mounting spare includes horizontal bar, and the both ends fixed first buckle with vertical support fixed connection of horizontal bar, and the horizontal bar is opened in the sliding slot, and the sliding slot is slidably provided with a plurality of hydrophone holder's of low -noise hydrophone's hydrophone holder, advantage: realize the adjustment of different interval between hydrophone array element, and ensure that hydrophone array can work at the same water depth height.

The application relates to the technical field of seabed communication and discloses an eccentric structure optical fiber hydrophone array which comprises a cable main body, an eccentric glue-filling plug core assembly fixedly arranged at one end of the cable main body, a threaded adapter assembly fixedly arranged outside the cable main body and located at one side of the eccentric glue-filling plug core assembly, and a support framework assembly fixedly installed outside the cable main body and located at the side, away from the eccentric glue-filling plug core assembly, of the threaded adapter assembly. The hydrophone and the delay line are oppositely arranged inside the fiber-receiving box. Compared with a single hydrophone, the delay line can flexibly adjust parameters such as the length of the wound optical fiber according to requirements. The parameters of the hydrophone are determined in advance, project time is shortened, and cost is saved. Through the V-shaped ring multilayer sealing structure, the V-shaped ring sealing nut can press the V-shaped ring pressing ring, the V-shaped ring middle ring and the V-shaped ring supporting ring, radial sealing force is generated, and high sealing performance is achieved.

The application belongs to the field of underwater target direction estimation, and combines a linear prediction algorithm with an ETAM algorithm of a vector hydrophone array to estimate the direction of an underwater target. Specifically, the application comprises the following steps: 1) constructing a data matrix of a virtual array after synthetic aperture by using the principle of the ETAM algorithm of the vector hydrophone array; 2) performing high-order linear prediction to solve forward and backward linear prediction coefficient vectors of the matrix; 3) extending the virtual array by k elements to the right or to the left; and 4) performing direction estimation on a signal matrix received by the extended virtual array in the previous step by using a conventional beam forming algorithm of the vector hydrophone array to obtain the target angle. The DOA estimation method of the moving platform vector hydrophone array based on the linear prediction and the ETAM algorithm can realize target direction estimation under the condition of lower signal-to-noise ratio and fewer array elements, and improves the target direction estimation precision and resolution of the underwater moving array.

The application discloses a working depth balancing estimation method and system of an underwater unmanned underwater vehicle, and the method comprises the following steps: A, calculating sound velocity gradient data by using temperature, salinity and depth data; B, setting simulation parameters of simulation transmission depth, propagation distance and frequency according to the sound velocity gradient data, and generating a configuration file for storing environmental parameters, transmission parameters and target parameters; C, calculating propagation loss data / datasets by using an acoustic toolbox Kraken and / or an acoustic toolbox Bellhop; and D, calculating the propagation loss data / datasets by using a weighted median algorithm to obtain an estimated value of the working depth. By efficiently utilizing the estimation method of the sound propagation path depth and combining the application of the underwater unmanned underwater vehicle, flexible target detection of multiple regions and multiple types of targets in a complex environment can be realized, and the target detection probability is improved on the basis of the traditional fixed depth arrangement of a hydrophone array for target detection.

The application discloses a kind of shore base hydrophone array and underwater unmanned vehicle cooperation's underwater target pure bearing tracking system, belong to underwater passive target detection system field, system is by shore base / sea bed hydrophone static node and AUV dynamic node constitute heterogeneous observation network, each node is configured with hydrophone array, positioning and navigation, time synchronization, underwater acoustic communication, storage and processor hardware, processor runs measurement credibility evaluation module, heterogeneous space-time alignment module (fixed delay cache+pose interpolation+forward-backward smoothing), joint state estimation module (RLS+PF+IMM) and quality perception consistency fusion module;AUV node also runs observation geometry optimization control module, system is unified heterogeneous modeling to static node and dynamic node, in false alarm, delay, out of order, packet loss and pose time-varying actual underwater acoustic engineering conditions realize the high-precision, high robustness continuous passive cooperative tracking of underwater slow target.

The present application belongs to the field of underwater acoustic signal processing and underwater target positioning technology, and relates to a low-cost pseudo-bistatic passive acoustic positioning method and system. The system adopts a four-element hydrophone array in combination with a single auxiliary hydrophone to form a short-baseline pseudo-bistatic structure, and has both direction-finding and ranging capabilities. Through adaptive bearing estimation, beam signal purification, Hilbert envelope anti-multipath and weighted generalized cross-correlation time delay estimation, combined with synchronization error compensation, confidence evaluation and trajectory constraint, high-precision two-dimensional passive positioning is realized. The present application uses bearing constraint to reduce the two-dimensional positioning calculation to one-dimensional distance estimation, which significantly reduces the hardware cost and system synchronization complexity while ensuring the accuracy of angle measurement and distance measurement, effectively suppresses the shallow water multipath interference, improves the positioning stability in low signal-to-noise ratio environment, and is suitable for passive detection and positioning of underwater targets in coastal, shallow water and other waters.

The application discloses a hydrophone array test fixture, which comprises a base plate and at least two fixture assemblies, the base plate is connected with a test platform for vibration test, and the base plate can vibrate synchronously with the test platform. Each fixture assembly comprises a fixture seat and at least one fixture cover, the fixture seat is fixedly connected with the base plate, the fixture seat can vibrate synchronously with the base plate, the fixture seat is formed with a first clamping groove, the extending direction of the first clamping groove is consistent with the extending direction of the fixture seat, and each fixture cover is connected with the fixture seat. The fixture cover is at least partially located above the first clamping groove, the fixture cover and the first clamping groove form a clamping space, and the clamping space is used for clamping a hydrophone. Through the above arrangement, the vibration test precision of the hydrophone array is improved.

The utility model provides a kind of big aperture buoy based on flexible fiber water-filled truss unfolding, belong to the field of ocean engineering equipment and underwater acoustic detection technology, it include: water surface floating subassembly;Floating body ontology;Electronic cabin subassembly;Baffle subassembly;Water filling and draining system.The utility model design compact structure, propose a new structure by water hardening several flexible water-filled tube to do buoy folding device, overall transportation size reduction, hidden wiring avoids winding and simplifies maintenance, without disassembly can high-precision repeatedly set angle, better than traditional exposed fixture.Flexible water-filled tube can reach the equivalent hardness close to steel material after water filling, integrated electronic cabin cooperates the design of water filling and draining system, realizes buoy intelligent control.Integrally injection moulded spherical node synchronously solves the problem of inaccuracy of hydrophone positioning and poor sealing, service life is significantly improved.Keep miniaturization transportation and quick deployment at the same time, form large aperture, high rigidity, node accurate hydrophone array surface under water.

This invention discloses a method, apparatus, and system for tilt attitude calibration of a vertical hydrophone array based on the ray-mapping method. The method includes: sequentially performing a pre-search estimation of the receiving-transmitting distance of each hydrophone in order from shallow to deep depth, minimizing the error between the theoretically calculated arrival time difference between the direct wave and the reflected wave from the sea surface and the actual extracted time difference, thereby obtaining the optimal distance estimate for each hydrophone in the pre-search stage; recalculating the optimal direct wave arrival time for each hydrophone using the optimal distance estimate obtained from the pre-search; and again, sequentially fine-tuning and optimizing the receiving-transmitting distance of each hydrophone in order from shallow to deep depth, iteratively searching for the distance estimate that most closely matches the theoretical direct wave arrival time calculated based on the pre-search estimate with the actual measured value. This invention provides a marine vertical receiving array attitude calibration scheme that is independent of external assistance, highly accurate, robust, and computationally efficient.

The application discloses a kind of underwater target positioning methods based on underwater acoustic particle velocity polarization processing.The method includes: arranging vector hydrophone array and carrying out underwater acoustic signal acquisition, and write the vector received signal of vector hydrophone array into tensor form;The tensor received signal of vector hydrophone array is carried out high-order singular value decomposition and the noise subspace of each dimension information matrix is solved by truncation to n module expansion left singular matrix;Array manifold matrix of vector hydrophone array is constructed and is written into polarization array manifold tensor;Azimuth-polarization two-dimensional spectrum search is carried out using array manifold tensor and noise subspace, and the azimuth and polarization parameters of the detected target are obtained from two-dimensional spectrum peak value.The underwater target positioning method provided by the application can accurately estimate the polarization parameters and the angle of arrival of incident signal, which helps to complete the underwater acoustic signal information based on frequency, wave number, mode and other characteristics by means of polarization parameters, and significantly improves the underwater target detection capability.

The present application belongs to the field of underwater acoustic signal processing and underwater target positioning technology, and relates to a low-cost pseudo-bistatic passive acoustic positioning method and system. The system adopts a four-element hydrophone array in combination with a single auxiliary hydrophone to form a short-baseline pseudo-bistatic structure, and has both direction-finding and ranging capabilities. Through adaptive bearing estimation, beam signal purification, Hilbert envelope anti-multipath and weighted generalized cross-correlation time delay estimation, combined with synchronization error compensation, confidence evaluation and trajectory constraint, high-precision two-dimensional passive positioning is realized. The present application uses bearing constraint to reduce the two-dimensional positioning calculation to one-dimensional distance estimation, which significantly reduces the hardware cost and system synchronization complexity while ensuring the accuracy of angle measurement and distance measurement, effectively suppresses the shallow water multipath interference, improves the positioning stability in low signal-to-noise ratio environment, and is suitable for passive detection and positioning of underwater targets in coastal, shallow water and other waters.

The present application belongs to the field of underwater target direction estimation, and relates to a vector hydrophone moving array DOA estimation method with array element angle deviation, comprising the following steps: 1) obtaining an array element angle deviation matrix and performing coarse estimation on the array element angle deviation matrix; 2) reconstructing the coarse estimation result of the array element angle deviation matrix to obtain a reconstructed angle deviation matrix; 3) calculating an estimated value of a signal matrix based on the angle deviation matrix; alternately iterating the estimated value of the signal matrix and the reconstructed angle deviation matrix to obtain a restored array receiving signal matrix; and 4) performing vector hydrophone array ETAM algorithm and beam forming based on the restored array receiving signal matrix to estimate the target direction. The present application provides a vector hydrophone moving array DOA estimation method which can effectively improve the estimation accuracy.