143 results about "Hydrophone array" patented technology

The invention provides a civil air defense engineering concealed conduit leakage positioning method based on acoustic characteristics, and belongs to the technical field of civil air defense engineering. An acoustic signal acquisition network is constructed by deploying a high-sensitivity hydrophone array, and signals are preprocessed by using a time division multiple access technology and a pulse compression technology; and carrying out time-frequency analysis by applying wavelet transform to extract acoustic features. A time reversal mirror technology is introduced to identify direct propagation and multipath reflection signals, a fluid acoustic coupling propagation equation is constructed to analyze a leakage sound source mechanism, and pipe network topological information and a sound wave speed correction function are combined to compensate a measurement error. Wherein the deep learning pipe network acoustic propagation multi-modal model is fused with a pipeline structure encoder, an acoustic feature extractor and a position prediction decoder, and high-precision leakage positioning and degree evaluation in a complex environment are realized through a three-stage pre-training strategy; the technical problem that it is difficult to accurately locate the position of a leakage point in the complex pipe network environment of civil air defense engineering is solved.

The invention provides an underwater sonar target detection system and method. The underwater sonar target detection system comprises an optical fiber hydrophone array module which comprises a plurality of optical fiber hydrophone units, each unit comprises an optical fiber Bragg grating sensor and a sound pressure signal demodulation device, and the optical fiber hydrophone array module is used for collecting underwater sound wave signals in real time and converting the underwater sound wave signals into first electric signals; the sonar transmitting-receiving array module comprises a broadband sonar transmitter, a multi-beam receiver and a signal preprocessing circuit, and is used for actively transmitting a frequency modulation continuous wave signal, receiving a target reflection echo and generating a second electric signal; and the multi-mode signal fusion processing module comprises a high-speed data acquisition card, a self-adaptive noise suppression unit and a time-frequency analysis unit. The underwater sonar target detection system and method provided by the invention have the advantages of relatively high reliability, relatively high detection performance, relatively accurate cross-modal signal fusion and capability of performing intelligent target identification and tracking.

The invention discloses a device for acoustically monitoring suspended sediment concentration and section particle size mean value of an ocean and a river, and relates to the technical field of ocean and river water environment monitoring. The four groups of piezoelectric ceramic transducers at the transmitting end are used for transmitting sound pulses with multiple frequencies into the same water body, and the broadband hydrophone array at the receiving end is used for synchronously receiving acoustic backward scattering signals which are scattered back. Wavelet threshold denoising and frequency domain filtering are combined, acoustic back scattering signals are preprocessed, turbulence and biological noise are eliminated, nonlinear errors caused by the particle size-concentration coupling effect are solved through an inversion algorithm fusing attenuation and scattering signals and in combination with a dynamic hierarchical data processing technology, and the accuracy of the acoustic back scattering signals is improved. The device realizes high-precision real-time measurement of suspended sediment parameters in ocean and river environments, has the capability of adaptive correction of environmental parameters, and is suitable for scientific research and engineering monitoring scenes.

A method is provided to measure the complex sensitivity of hydrophone data channels across a range of frequencies by using a water-filled tank with proximate boundaries. A hydrophone array and reference hydrophone are helically affixed to a test fixture resting on a rotation platform. When the test fixture is submerged in the tank; the platform rotates about a contour of the platform in intervals for a predetermined time interval before indexing to the next angle. Signals transmitted by an acoustic projector in the tank are received on the hydrophones of the line array and the calibrated reference hydrophone. Electrical signals from the reference hydrophone are transmitted over an electrical cable and received by the acoustic data processor for use in calibrating the hydrophone line array. Electrical signals from the hydrophones of the hydrophone line array are also transmitted to the data processor.

The invention discloses a sound barrier sound insulation characteristic evaluation method suitable for a real ship complex sound field, and belongs to the technical field of real ship sound barriers, and the method comprises the steps: arranging hydrophone arrays at acoustic mirror symmetry positions at two sides of a real ship fairing sound barrier to form an in-situ measurement pair; controlling the ship to sail at a plurality of navigational speeds, and synchronously acquiring sound pressure time domain signals on two sides; carrying out preprocessing and time-frequency analysis on the signals, and calculating sound pressure levels of a sound facing surface and a sound backing surface to obtain an in-situ sound pressure level difference; and based on the sound pressure level difference at different navigational speeds, analyzing the change rule of the sound insulation performance along with the frequency and the navigational speed, and carrying out comprehensive evaluation. In addition, by arranging a vibration sensor and a turbulence measuring device, path separation of structural sound and flow-induced noise is achieved, spatial coherence weighted average is introduced, and the accuracy and representativeness of evaluation under a complex sound field are improved. The method overcomes the limitations of laboratory test environment distortion and single working condition, and can truly and comprehensively reflect the actual sound insulation efficiency of the sound baffle in the dynamic navigation of a real ship.

The invention discloses a digital equivalent source sound field reconstruction system based on an underwater complex sound field environment. The digital equivalent source sound field reconstruction system comprises a sound pressure acquisition module which acquires radiation sound pressure data on a measurement point through a hydrophone array; the intelligent analysis module is used for performing shallow sea sound pressure Green function derivation by utilizing a shallow sea Pekeris waveguide model based on the radiation sound pressure data, and constructing an underwater sound field equivalent source equation; the compressed sensing module is used for converting an underwater sound field equivalent source equation into a compressed sensing problem based on the underwater sound field equivalent source equation, and solving a norm for reducing L1 by adopting an algorithm under an accelerated near-end gradient to obtain compressed sensing equivalent source intensity; and the sound field reconstruction module is used for constructing a free field green function, obtaining underwater reconstruction sound pressure by combining the free field green function with the compressed sensing equivalent source intensity, realizing digital equivalent source sound field reconstruction of an underwater complex sound field environment, improving data processing efficiency and reducing requirements on computing resources.

The invention discloses a vector hydrophone array orientation estimation method for performing tensor decomposition by using a propagation operator, relates to the technical field of vector hydrophone array orientation estimation, and discloses a vector hydrophone array orientation estimation method for performing tensor decomposition by using a propagation operator. The method comprises the following steps: firstly, constructing a three-dimensional array manifold tensor composed of an array direction matrix and a vector hydrophone output matrix; respectively expanding received signal tensors according to three modes, solving a propagation operator based on a column block covariance matrix, constructing a normalized signal subspace, establishing a spatial spectrum function with a noise subspace, and obtaining a pitch angle and an azimuth angle of a sound source through spectrum peak search; according to the method, high-order singular value decomposition is avoided, the operand is greatly reduced, meanwhile, high resolution and low sidelobe direction finding performance are kept, and the method is suitable for a real-time underwater acoustic direction finding system of a ship-borne platform, a buoy platform and an unmanned platform.

The utility model belongs to the technical field of overwater monitoring equipment, and particularly relates to a positioning buoy capable of automatically adjusting the laying depth of a hydrophone array. The utility model provides a positioning buoy capable of automatically adjusting the laying depth of a hydrophone array. The positioning buoy comprises a depth sensor, a cable assembly and a communication assembly. When the laying depth of the hydrophone array needs to be adjusted, the controller firstly reads a measurement value of the depth sensor. And if the measured value does not accord with the preset target depth, the controller sends an instruction to the motor, so that the motor rotates the cable roller by a certain angle according to the preset direction, and the deeper cable is released or withdrawn. And the depth of the hydrophone array connected with the deeper cable is changed along with the change of the length of the deeper cable. By adjusting the depth of the hydrophone array, the positioning buoy can be suitable for wide-range underwater acoustic passive monitoring work, and is particularly suitable for being matched with a detected acoustic target which actively produces sound, such as an underwater vehicle on which an acoustic beacon is hung, so that an underwater positioning system is formed.

The invention discloses a digital twinning-AI prediction driven cofferdam directional micro-blasting system, which relates to the technical field of underwater blasting engineering, and comprises the following steps of: constructing multi-domain digital twinning, reading a compliance rule machine by a loading machine, fusing a hydrophone array, shore-based vibration and distributed optical fiber observation assimilation to form a baseline field; defining an isobaric surface leakage volume, a sector deflection angle, a closure degree and a frequency band energy ratio, and establishing two sets of equivalent boundary admittances and preselection of a switchable physical layer; training a multi-output AI element model, combining opportunity constraint and hard constraint, performing linkage optimization on a physical layer and a detonation network, and generating a linkage instruction and a sensitivity atlas; and small-dose trial explosion is executed by a hierarchical correction state machine, and on-line guarding and knowledge writing-back are carried out in combination with sequential ratio test and quantile tracking. And minute-level interpretable prediction can be realized, leakage and direction drift are inhibited, the safety of an ecological structure is guaranteed, and the construction period and the cost are reduced.

The invention provides a method and system for measuring the sound source radiation sound power level in a reverberation pool, and the method comprises the steps: constructing a reverberation test system according to a preset standard, laying a hydrophone array and a to-be-measured sound source in the reverberation pool, and enabling the array element spacing of the hydrophone array to be smaller than or equal to the minimum half-wavelength; enabling the to-be-detected sound source to emit a to-be-detected signal, and collecting complete time domain sound pressure data of the to-be-detected signal; calculating the mean square sound pressure level of the measuring point in the reverberation control area based on the steady-state time domain sound pressure data of the sound signal; calculating complete time domain sound pressure data of all array elements based on Fourier transform to obtain a sound energy density change curve, and fitting the sound energy density change curve to obtain reverberation time; sound field correction is obtained through calculation according to the reverberation time, and the radiation sound power level of the sound source to be measured is obtained according to the sound field correction. According to the invention, the experiment process is simplified, the measurement efficiency is obviously improved, the experiment cost is reduced, and a new technical approach is provided for the rapid measurement of the water pool of the sound source radiation sound power level.

The invention relates to an underwater target passive positioning technology in a horizontally changing shallow sea waveguide, and mainly relates to a matching mode target passive positioning method combined with a bidirectional coupling normal wave theory. According to the method, firstly, a bidirectional coupling normal wave model based on a multi-modal admittance method is established for the boundary value problem of a Helmholtz equation in a horizontal change shallow sea waveguide, the model considers modal coupling and backscattering effects, and a high-precision copy sound field and a modal coefficient calculation result of the copy sound field can be provided; then extracting a modal coefficient of a measurement field from data received by the vertical hydrophone array; and finally, processing the modal coefficient of the copy field and the modal coefficient of the measurement field by using a matching mode processor to obtain a fuzzy surface, and estimating the distance and depth information of the underwater target. According to the invention, the conventional matching mode positioning algorithm is improved from the perspective of underwater acoustic physics, and the positioning performance of the conventional matching mode algorithm in the horizontally changing shallow sea waveguide is improved.

The invention relates to a water turbine flow channel discharge noise monitoring and fault identification system and method, interference type optical fiber hydrophone arrays are arranged at a top cover between a rotating wheel and a movable guide vane, a volute mandoor and a draft tube straight cone section mandoor, discharge noise in a flow channel is directly measured, and after photoelectric conversion, signal amplification, analog-to-digital conversion and band-pass filtering, the discharge noise in the flow channel is detected. Blind source separation is carried out by using FastICA, features are extracted in combination with empirical mode decomposition (EEMD) and an energy method, audible sound and ultrasonic frequency bands are monitored at the same time, and feature type identification is carried out in combination with an existing fault feature database based on dynamic time warping (DTW) and a support vector machine (SVM) algorithm; the output signal-to-noise ratio and the anti-interference capability of the system are improved, multi-directional analysis of discharge noise characteristics is achieved, the monitoring range is wide, the fault recognition speed is high, the accuracy is high, and the system is mainly used for monitoring the running state of the water turbine in real time, finding and early warning faults in time and improving the running maintenance efficiency of the water turbine.

The present invention provides a method and system for calibrating the attitude of a fiber optic vector hydrophone and its array. The attitude calibration method includes: a sound source transmits a signal and rotates around the fiber optic vector hydrophone; an acoustic energy flow method is used to obtain the azimuth angle θ of the fiber optic vector hydrophone corresponding to the sound source; the X+ axis direction of the fiber optic vector hydrophone is determined based on the obtained azimuth angle; the deviation angle Δθ between the current attitude heading of the hydrophone and the X+ axis direction is determined based on the attitude sensor in the fiber optic vector hydrophone, and the fiber optic vector hydrophone is attitude calibrated so that the X+ axis direction of the fiber optic vector hydrophone coincides with the attitude heading. This solves the problem in the prior art of being unable to ensure that the X+ axis of the fiber optic vector hydrophone is consistent with the heading angle of the attitude sensor during navigation, thereby improving the application capability of the fiber optic vector hydrophone array in target azimuth measurement and the array azimuth estimation accuracy.

A survey system including a multibeam echo sounder having a projector array and a hydrophone array uses a multi-component message to ensonify one or more fans to estimate a Doppler velocity.

The invention relates to a multi-source intelligent combined pose measurement method for a floating hydrophone array, and the method comprises the following steps: 1, obtaining the pose information of each node of the hydrophone array through a multi-source sensing module, and synchronously receiving sound signals and extracting the TDOA information of each node under the condition that the sound source position is known; step 2, constructing a measurement equation based on TDOA information, and performing inverse solution on the position of each node of the hydrophone array in combination with a hyperbolic positioning principle and a sound velocity model; according to the method, an inverse solution positioning mode of'known sound source position and inverse solution of receiving array node position 'is adopted, a flexible underwater acoustic array dynamic measurement scene under the traction of a floating platform is specially aimed at, the technical limitation that traditional TDOA and USBL positioning depends on a fixed geometric structure is broken through, the method does not need to arrange a plurality of reference receiver arrays, and the positioning accuracy is improved. And a high-precision synchronous clock system is not needed, and high-precision acoustic positioning can be realized only by depending on a single sound source and the distributed nodes, so that the system complexity and the field deployment cost are remarkably reduced.

The present invention discloses an adjustable submersible noise measurement system, comprising an underwater instrument cabin, an optoelectronic transmission cable, an optical fiber hydrophone array, an expander, a mooring device, and a surface communication buoy. The optical fiber hydrophone array receives noise signals radiated by underwater targets and transmits the signals to the underwater instrument cabin via the optoelectronic transmission cable. The underwater instrument cabin is fixed to the seabed by the mooring device and connected to the surface communication buoy. The expander is fixed to the seabed by a hook anchor, and the optical fiber hydrophone array is adjusted by the expander to achieve horizontal deployment. The underwater instrument cabin and the expander are positively buoyant structures, thereby forming a trapezoidal structure underwater. The present invention utilizes the expander to retract and extend the optoelectronic transmission cable and hook anchor to control the entire array to be horizontal underwater and stabilize the array's posture. When the array's posture reaches the required posture for equipment testing, the expander stops working, and the equipment is now in a silent state and does not generate any noise, thereby reducing the impact of noise generated by the equipment itself.

The present application relates to the technical field of ultra-short baseline direction measurement data processing, and particularly relates to a direction estimation method of a multi-element stereo hydrophone array. The method approximates sound waves as plane waves and establishes a mathematical relationship between time difference of arrival (TDOA) and a direction vector, takes TDOA as an observation value, calculates a direction vector estimation value according to a weighted least square method, then calculates the equivalent weight of the observation value according to an equivalent weight function, further replaces the original observation value weight array with an equivalent weight array, and recalculates the direction vector according to the weighted least square method, iteratively calculates the equivalent weight and the direction vector, until the difference between the direction vectors of two consecutive times is less than a manually set threshold, and the direction vector is output as the direction of the multi-element stereo hydrophone array. The present application can weaken the influence of the sound ray bending which is not considered in the direction estimation function model, and consider the influence of the array element spacing and the target direction on the direction estimation, thereby improving the accuracy and reliability of the direction estimation of the multi-element stereo hydrophone array.

The invention discloses a hydrophone array multi-sound-source positioning method based on a frost ice optimization algorithm, and belongs to the field of sound source positioning. According to the method, a linear hydrophone array is constructed, an underwater sound source positioning scene is set, and a sound source signal is collected and processed to obtain a receiving signal; a MUSIC algorithm is used to process the received signal, a spatial spectrum is generated to preliminarily estimate information such as an azimuth angle and a pitch angle of a sound source, normalization processing is carried out on the spatial spectrum, a gravitational force area and a repulsive force area are divided, and a gravitational force-repulsive force type artificial potential energy field is constructed; an independent sub-population is initialized for each sound source by adopting a frost ice RIME optimization algorithm, individual positions are updated in combination with an artificial potential energy field and a frost puncture mechanism in an iterative updating process, and particles with the highest fitness are selected as final estimation positions through iterative search. The method overcomes the limitation of a traditional optimization algorithm, remarkably improves the precision and reliability of sound source positioning, and is particularly suitable for a multi-sound-source positioning scene in a complex underwater sound environment.

The application discloses a passive sonar ranging method and device for a linear fiber hydrophone array, which comprises the following steps: performing primary beam forming according to original data at a first position, searching for a first azimuth angle with the maximum signal strength according to the primary beam forming result; performing secondary beam forming according to original data at a second position, searching for a second azimuth angle with the maximum signal strength according to the secondary beam forming result; and then calculating the target distance according to the first azimuth angle, the second azimuth angle, the speed and the running time. Compared with triangulation, the method and the device can reduce the measurement deviation caused by the uncertainty of the position of the fiber hydrophone array, the distance variance is smaller, and the reliability is higher in actual use.

The application discloses a kind of ship underwater noise tracking monitoring device and method, the method includes the following steps: 1) the monitoring device is installed to ship;2) keep ship in the channel in the state of stop, each hydrophone is monitored in the channel ambient noise, and data acquisition equipment records ambient noise signal;3) according to test condition, ship equipment is normally opened or runs;4) ship is normally navigated in the channel, and data acquisition equipment records the sound wave signal measured by hydrophone;5) based on the ambient noise monitored in step 2), the sound wave signal measured by each hydrophone is removed ambient noise, and all the noise-removed underwater radiated noise signals of the ship are analyzed and processed.The application is arranged with tracking measurement hydrophone array around the ship, and the ship is monitored under various conditions in line with the actual situation, with the real ship flow field around the ship during navigation, and the monitoring result has high accuracy.

The present invention belongs to the technical field of underwater cable laying, and specifically relates to an unmanned autonomous deployment system for hydrophone array cables based on multi-submersible collaborative programmable systems. After an operating vessel carrying a hydrophone array cable reel arrives at an operating area, multiple groups of unmanned submersibles are released, and the front end of the hydrophone array cable passes through the lower sleeve of a three-way connector carried by each unmanned submersible in sequence. The operating vessel assigns tasks to each unmanned submersible. During the movement of the unmanned submersible, a tension sensor monitors the tension between the electromagnet device and the motor slider, thereby calculating the tension on the hydrophone array cable. The tension is adjusted by the movement of the motor slider on the guide rail to ensure that the tension fluctuation of the hydrophone array cable during underwater deployment is controlled within ±2%, achieving constant tension control. When all unmanned submersibles arrive at the designated location, the electromagnet devices they carry are simultaneously controlled to be disabled, and the three-way connector carrying the hydrophone array cable sinks to the predetermined position, completing the deployment task.

The application discloses a kind of robust hydrophone array azimuth estimation method.This patent scheme introduces amplitude-phase error correction, utilizes phase error vector and energy normalization, realizes the correction of amplitude-phase error.Covariance matrix is reconstructed using the corrected data, and spatial spectrum is calculated using the reconstructed covariance matrix, then the first order differential function of spectrum function is calculated, and the spectrum peak search is carried out on the differential spatial spectrum curve to estimate the incident signal direction of arrival.The simulation experiment and lake test experiment results show that the method greatly reduces the influence of amplitude-phase error on DOA estimation performance, improves the estimation accuracy of direction, and has low computational complexity.This patent scheme has important application value in submarine and ocean mobile observation platform and other ocean instruments, and has high practical engineering application value.

The invention discloses a local cooperative sensitization distributed optical fiber low-frequency underwater acoustic signal pickup solid-state array, and belongs to the technical field of underwater acoustic low-frequency signal measurement, the array comprises a plurality of array elements, all the array elements are connected through a common sensing optical fiber, and the outer surface of the sensing optical fiber is coated with a sound-sensitive material; a sensing grating is arranged in the sensing optical fiber between the adjacent array elements, and the outer sides of the array elements and the sensing optical fiber are coated with a polyethylene pipe. According to the local cooperative sensitization distributed optical fiber low-frequency underwater acoustic signal pickup solid-state array, the array structure is simple, the array element sound pressure sensitivity consistency is good, compared with interference type hydrophone array elements of the same number, the cost is greatly reduced, underwater acoustic signal detection of underwater low-frequency acoustic signals within the range of 20 Hz-2 kHz can be achieved, and the underwater acoustic signal pickup effect is good. The method has high sensitivity and a larger underwater acoustic signal detection aperture.

The invention discloses a dynamic adjustable acceleration sensor with high sensitivity and low noise, and relates to the field of acceleration sensors. According to the acceleration sensor, a plurality of cantilever beam supporting sheets are stacked in sequence and are connected with a base; a piezoelectric element is fixed in a central circular area of the cantilever beam supporting sheet on the topmost layer, a plurality of mass sheets are sequentially stacked in an outer ring girdle area, longitudinal excitation deformation is easily conducted to the piezoelectric sheet, and stress is concentrated at the joint of the cantilever beam supporting sheet on the bottommost layer and the base under the condition of transverse excitation, so that the directivity of the acceleration sensor is better, and the stability of the acceleration sensor is improved. The charge output in the horizontal direction is small; the detachable assembly of the cantilever beam supporting sheet and the mass sheet is beneficial for improving the adjustability of performance parameters and the phase amplitude consistency in array application, and the high-sensitivity adjustable structural design and the collaborative optimization design of material physical property parameters jointly achieve high sensitivity, excellent bandwidth adjustability and extremely low background noise. The method is suitable for complex underwater sound environments such as hydrophone arrays.

The present invention discloses an adaptive underwater sound source passive localization method and system. The method includes: acquiring the signals received by a hydrophone array; converting the signals received by the array to the frequency domain by using fast Fourier transform, obtaining the effective frequency band of the target signal source through spectrum analysis, and constructing a steering vector estimation; calculating the covariance matrix of the signals received by the array, and obtaining the eigenvalues and eigenvectors of the covariance matrix through eigenvalue decomposition; constructing a weight matrix by using the eigenvalues of the covariance matrix, weighting all the eigenvalues of the covariance matrix with the weight matrix to form a fully weighted spatial vector, and realizing adaptive fully weighted MUSIC spatial spectrum estimation through iterative operation and setting of iterative termination conditions; and obtaining the estimated value of the arrival azimuth. The present invention avoids the need for estimating the number of signal sources in the conventional MUSIC algorithm, and solves the situation of performance degradation of the beamformer caused by steering vector mismatch and noise subspace division error in practical applications.

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 optical fiber hydrophone array optical path difference test system and method, by wideband light source, tunable laser, isolator, acoustooptic modulator, photoelectric detector, data acquisition system, computer is formed, wideband light source and tunable filter are used to realize wavelength scanning, output wavelength is the continuous light of λ;Acoustooptic modulator enters the continuous light of optical fiber hydrophone array and is modulated into pulsed light;Photoelectric detector converts optical signal into electrical signal;Data acquisition system shows and converts the signal collected by photoelectric detector into digital signal and then transmits to computer, and optical path difference is calculated by computer.The application has the characteristics of simple structure, small mathematical operation amount, wavelength adjustable, high measurement accuracy, strong system reliability and the like, meets the real-time online measurement demand of optical path difference in the process of optical fiber hydrophone array, and has very wide application prospect.

A gridless coherent signal direction-of-arrival estimation method based on alternating projection according to the present invention is characterized in that: the patented method uses a hydrophone array installed on an underwater vehicle to receive signal data to construct a positive semi-definite matrix S0, and uses the projection method to alternately project S0 onto a rank-constrained set and a Toeplitz matrix with averaged main diagonal elements. Secondly, the convergence degree of S0 is judged, and then T i (u) is subjected to reduced-dimensional space smoothing-singular value decomposition. Finally, z is obtained by using the polynomial root-finding method, and the incident angle of the coherent signal is solved by using the corresponding mapping relationship. The patented method effectively realizes the angle estimation of coherent signals. Secondly, the polynomial root-finding method is used instead of spectral peak search, which effectively reduces the computational amount, improves the robustness and real-time performance of the algorithm, and has high estimation accuracy, having important engineering application value.

A half-spectrum search low-complexity azimuth estimation method for sound pressure and vibration velocity combined dimension reduction processing relates to the field of array signal processing, and comprises the following steps: acquiring output signals of a vector hydrophone array under N snapshots, and establishing a far-field target sound signal model; constructing a sampling covariance matrix for the output signal, and separating the sampling covariance matrix into a real part and an imaginary part; the vibration velocity signals in the vector array are synthesized in the guide angle direction through Givens transformation, a synthesized vibration velocity signal is constructed, and the synthesized vibration velocity signal and the sound pressure signal are jointly processed to construct a joint covariance matrix; constructing a DOA estimation model by using the real part of the joint covariance matrix, and constructing a spatial spectrum function based on the DOA estimation model and the real part of the joint covariance matrix; and searching a spectral function peak value in a half interval of a scanning angle space, and judging a real target angle according to a MUSIC algorithm. According to the method, the calculation amount is reduced while the estimation performance is ensured, and the problem that a traditional DOA estimation method is high in calculation complexity is solved.

The invention discloses a flexible braided layer reinforced optical fiber hydrophone array, which is characterized in that an inner protection assembly sleeves the outer side of a layer stranded cable, the end part of the inner protection assembly is provided with a pipe cable joint, the axis of the pipe cable joint deviating from the inner protection assembly is provided with a cable via hole, and the cable via hole is used for the layer stranded cable to pass through and is fixedly connected with the layer stranded cable so that the layer stranded cable is arranged deviating from one side; the hydrophone probe and the layer stranded cable are arranged on the two sides in the inner protection assembly respectively, the framework supporting assembly is arranged in the inner protection assembly, the two ends of the sealing connector assembly can be used for pipe cable connectors to be connected in a sealed and inserted mode, and the flexible woven outer layer is formed by integrally weaving a non-metal flexible woven piece and comprises a first woven section and a second woven section which are different in radial size. The first weaving sections and the second weaving sections are attached to and wrap the inner protection assembly and the sealing connector assembly in a one-to-one correspondence mode, the tensile property of the array is remarkably improved, meanwhile, the abrasion resistance of the outer surface of the array can be remarkably improved, and integrated weaving forming of the flexible weaving outer layer is easy to achieve.