655results about "Sonic/ultrasonic/infrasonic transmission" patented technology

This invention relates to a modular sensing, communication, and analytics platform. The platform includes a modular device network having a communication module, a main module, and at least one modular device, where the communication module, the main module, and the at least one modular device use acoustic signals, visual signals, light signals, and / or radio frequency to establish a communication link between the communication module, the main module, and the at least one modular device.

A method of decoding a received communication signal is provided. The method may comprising converting the received communication signal to the frequency domain to provide frequency domain data. The method may further comprise combining amplitudes of one or more selected frequency components of the frequency domain data, the one or more frequency components being selected according to a predefined communication symbol comprising one or more selected frequency tones corresponding to the one or more selected frequency components. The method may further comprise detecting the predefined communication symbol in the received communication signal depending on the combined amplitudes of the one or more selected frequency components of the frequency domain data.

The invention discloses a multi-mode underwater acoustic communication system and communication method based on a heterogeneous dual-core architecture, and belongs to the technical field of underwater acoustic communication. The multi-mode underwater acoustic communication system comprises a main control module, an acquisition module and a transmitting module; the main control module adopts a dual-core heterogeneous processor OMAPL138 formed by an ARM core processor and a DSP core processor; inter-core communication is carried out between the ARM core processor and the DSP core processor through a shared memory and interruption; the ARM core processor is responsible for protocol analysis, task scheduling and man-machine interaction, and the DSP core processor focuses on signal processing and real-time control and integrates four communication systems, a channel evaluation module and the like. The problems that application of a single communication mode is limited and underwater acoustic communication links in different complex sea areas are unstable are effectively solved, and the deep sea area underwater vehicle information collaboration and return and deep sea area observation and monitoring network system capacity are effectively improved and guaranteed.

The invention relates to the field of bionic hidden underwater acoustic communication, in particular to an underwater acoustic communication hidden performance evaluation method, device and equipment based on a neural network, and the method comprises the steps: carrying out the feature extraction of a to-be-evaluated underwater acoustic signal, and obtaining a feature sequence of the to-be-evaluated underwater acoustic signal; converting the feature sequence into a two-dimensional matrix with a preset size; the two-dimensional matrix is predicted according to a pre-trained underwater acoustic signal classification neural network model, a probability matrix is obtained, the probability matrix comprises a first probability and a second probability, the first probability represents the probability that the to-be-evaluated underwater acoustic signal belongs to the bionic modulation signal, and the second probability represents the probability that the to-be-evaluated underwater acoustic signal belongs to the bionic modulation signal; the second probability represents the probability that the underwater acoustic signal to be evaluated belongs to the real marine organism signal, and the underwater acoustic signal classification neural network model comprises an input layer, a first convolutional layer, a first pooling layer, a second convolutional layer, a second pooling layer, a global pooling layer and a full-connection output layer which are connected in sequence. The dependence on artificial feature design in a traditional recognition method is reduced, and the recognition stability in a complex underwater environment is improved.

The invention discloses a deep sea mineral lifting unmanned transportation system. According to the system, an unmanned carrier-intelligent execution-elastic scheduling framework is constructed, and the system comprises four modules including unmanned carrying equipment, a communication network system, a scheduling control center and a support safeguard system. The unmanned carrying equipment realizes mineral transportation based on buoyancy driving; the communication network adopts a layered redundant architecture of underwater sound OFDM and a laser emergency link, and high-reliability communication and centimeter-level positioning are guaranteed; the scheduling control center improves the operation efficiency through intelligent task allocation and trajectory planning; the support and guarantee system integrates energy management, digital twin monitoring and emergency response mechanisms. The operation process adopts a mode of mainly unmanned autonomous and assisted by remote monitoring, and the links of ballast diving, acousto-optic docking, buoyancy regulation and control, mother ship dynamic unloading and the like are covered. The deep-sea mineral lifting efficiency, maneuverability and reliability are remarkably improved, and core technical support is provided for deep-sea resource development.

The invention discloses a marine phytoplankton abundance monitoring method based on data driving and an underwater acoustic network, and the method comprises the steps: building and training a multi-level spatial-temporal feature integration model based on the historical marine phytoplankton abundance and the corresponding marine environment data, and solving the optimal spatial position and monitoring time window of an underwater acoustic network node; constructing a teacher model which comprises a multi-layer cascade structure and a residual module and is used for channel prediction, and compressing the teacher model into a student model by adopting spatio-temporal knowledge distillation; the student model is trained, and channel state real-time prediction is realized at the underwater acoustic network node; on the basis of the optimal spatial position of an underwater acoustic network node and a real-time predicted channel state, adaptive underwater acoustic communication models and seasonal optimal routing strategies are matched, adaptive modulation and coding are executed at a link level, and monitoring of abundance of phytoplankton is completed based on an underwater acoustic network. According to the invention, the data throughput and prediction precision can be improved under strict energy consumption constraints.

The invention discloses an underwater sound environment sensing method based on multi-array-element sparse channel estimation. An underwater sound receiving end receives signals transmitted through an underwater sound multipath channel through a multi-array-element array; performing Hilbert transform on the receiving signal of each array element to obtain an analysis signal, and calculating a cross-correlation function of the analysis signal and the transmitting signal; based on the cross-correlation function, sparse channel parameters, including path amplitude and time delay, of each array element are estimated by adopting an orthogonal matching pursuit algorithm combined with a constant false alarm detection dynamic threshold value; the method comprises the following steps: constructing an array response vector by using sparse channel parameters of a multi-array element array, and searching and estimating angles of arrival, including a direction angle and a pitch angle, of a multipath signal through a spatial spectrum peak value; and based on the arrival angles, amplitudes and time delays of the direct path and the reflection path, inverting an underwater environment structure through a ray acoustic theory, including a reflection point distance and a reflection surface normal vector, so as to realize three-dimensional perception of the underwater reflector. According to the invention, multipath resolution can be improved, and false alarm and missing detection can be effectively reduced.

The invention discloses an underwater acoustic signal communication and positioning integrated method. The existing method does not jointly consider the problem of channel resource occupation caused by integration of communication and positioning. According to the method, mutually orthogonal Chirp subcarriers are used as communication signals, meanwhile, long Chirp signals are used as pilot frequency, and the pilot frequency and the communication signals are overlapped together to be sent at a sender, so that extra channel overhead caused by additional pilot frequency is saved, and the signal sending time interval is shortened. A receiver uses a plurality of pilot signals to perform joint Doppler estimation and compensation and time of arrival estimation, and the result of the time of arrival estimation is used for a positioning system and a communication system on the one hand. According to the demodulation mode, correlation calculation is carried out by using different Chirp subcarriers, and symbol demodulation is carried out according to correlation values. According to the communication and positioning integrated waveform design method, the signal sending time interval can be shortened, the system complexity can be reduced, and good communication performance is achieved.

The invention discloses an acoustic-electric cross-medium heterogeneous network end-to-end time delay analysis method based on random network calculation. The method comprises the following steps: firstly, constructing a heterogeneous protocol service model of an underwater acoustic (UWA) link and a radio (RF) link, and modeling an FC-ARQ mechanism and a CSMA / CA access behavior by adopting a Markov process; secondly, realizing cross-medium service coupling modeling by unifying time slot scale and introducing protocol conversion, time slot alignment and fragmentation recombination overhead; furthermore, the arrival and service yoke process is constructed based on the yoke theory, and a closed upper bound expression of the end-to-end time delay violation probability is deduced by using the stop time theorem. The method can accurately reflect time delay behaviors caused by non-conservation, asynchronization and protocol switching in a multi-medium system, and is suitable for performance evaluation and resource scheduling optimization scenes in an underwater wireless and air wireless fusion network.

The invention discloses a laser-induced sound cross-medium communication method based on passive relay PWM modulation, and relates to the technical field of cross-medium communication. The method comprises the following steps: adjusting the laser pulse width of to-be-sent information, and carrying out PWM modulation to obtain a PWM sequence; inputting the modulation sequence into a laser driving control module, and driving a laser to emit a laser pulse signal with specific pulse width change; laser energy is focused on the surface of a passive relay material, and when laser pulses with different pulse widths act on the material, different numbers of sound signals can be excited and generated; a receiving end captures sound signals propagating across media through a hydrophone, and demodulates the sound signals according to a mapping relation between pulse width and the number of the sound signals; and finally, original information is restored, so that cross-medium communication from air to water is completed. According to the invention, PWM modulation is combined with a passive relay material, and the system has the remarkable advantages of no need of underwater power supply, simple structure, high reliability and the like.

The present invention belongs to the field of marine underwater positioning, navigation and timing. Disclosed are an underwater navigation and communication integrated position service system and method. The system comprises a buoy base station, a submerged buoy base station, a seabed base station and a shore-based operation and control unit, and the system utilizes a three-dimensional base station network observation mode combining the buoy base station, the submerged buoy base station and the seabed base station. The position service system and method in the present invention have the capabilities of underwater acoustic navigation and communication, satellite positioning and communication, atomic clock timekeeping, hydrological measurement and responding to instructions of a shore-based operation and control unit, have the functions of autonomous, real-time and online base station position and clock calibration and sound velocity field correction, have the functions of base station position and clock calibration, and sound velocity field correction and control based on the shore-based operation and control unit, and can expand the range and functions of underwater position services, and provide accurate positioning, navigation and timing services for water-surface / underwater users.

The invention discloses an acoustic optical communication positioning method for an autonomous adjustment channel of an underwater robot, and the method comprises the steps: constructing an underwater dynamic acousto-optic fusion repeater, achieving the wide-area guaranteed-bottom connection with the underwater robot through an acoustic link, and providing meter-scale precision coarse positioning covering a whole operation region; the method provides prior information for rapid establishment of a subsequent optical link, further dynamically compresses an optical search area to realize rapid and accurate link establishment, and performs autonomous and smooth switching among acoustic, optical and acousto-optic hybrid transmission modes according to real-time link quality assessment (signal-to-noise ratio), thereby realizing acousto-optic deep coupling and cooperative scheduling, and improving the reliability of the system. The system has the advantages of long-distance reliable connection, short-distance high-speed data return, high-precision positioning and the like, and solves the core technical problems that the distance and the speed cannot be obtained at the same time and the positioning precision and the coverage range are mutually restricted in the prior art.

The invention relates to a high-precision photonic crystal waveguide signal detection method and device based on a diamond quantum sensor. The method comprises the following steps: acquiring a vibration signal transmitted by a phononic crystal waveguide through a diamond quantum sensor; performing frequency domain transformation on single-frame signals in the vibration signals in sequence to obtain single-frame frequency domain features; inputting the frequency components into a trained detector model, acquiring a long-range dependency relationship between frequency characteristics corresponding to different frequency components and context information between the frequency characteristics through a self-attention module, and correcting the frequency characteristics corresponding to the related frequency components according to the long-range dependency relationship and the context information; identifying an aggregation feature containing the corrected frequency feature through a classification layer to obtain a predicted binary numerical value corresponding to the single-frame frequency domain feature; the long-range dependency relationship means that the amplitude information and / or the phase information between the two frequency components with the frequencies exceeding the preset threshold value have an association relationship. The method can improve the signal detection precision.

The invention relates to the technical field of underwater communication, in particular to a collision avoidance method suitable for digital underwater acoustic communication, which is characterized in that a neighbor propagation delay mapping database is maintained at each communication node, and inter-node propagation delay information is acquired through passive monitoring and active detection. When a node wants to send data, combining delay mapping to predict a channel occupation time slot, and judging whether the sending is conflicted with an RTS / CTS handshake stage, a data transmission stage and an ACK (Acknowledgement Character) confirmation stage which are carried out by a neighbor; if a conflict risk exists, the node delays to send the RTS and then initiates handshake until the security window is finished, so that collision caused by hidden nodes and exposed nodes is avoided, meanwhile, parallel transmission under the conflict-free condition is allowed, the channel space-time multiplexing efficiency is improved, the network throughput can be remarkably improved, the data packet collision rate is reduced, and the network performance is improved. And the node access fairness is improved.

The invention relates to an underwater acoustic communication and positioning integrated signal design and processing method based on FDMA signal modulation, a medium and a device, and belongs to the field of underwater acoustic communication / positioning. And respectively modulating the integrated baseband signals to a plurality of pre-divided carriers with different center frequencies. Each carrier corresponds to an independent transmitter signal, and the center frequency interval of different transmitter signals is greater than the signal bandwidth. And the modulated signal is transmitted to an underwater environment through the underwater acoustic transducer. In the signal processing process, a band-pass filter bank is used for carrying out frequency separation on received signals, each filter corresponds to the center frequency of a transmitting signal, the separated signals are demodulated and decoded to recover original communication data, and the distance between a transmitter and a receiver is calculated by measuring time delay. And simultaneous communication interaction and high-precision positioning of multiple underwater users are realized.

The invention discloses a cross-medium wearable audio transmission system and a transmission method thereof, which are suitable for audio communication scenes in an air and water body junction environment such as a natatorium. The system comprises a shore transmitting terminal and an underwater receiving earphone, and adopts a blue-green light wave band as a transmission carrier to realize cross-medium wireless transmission of audio signals. The transmitting terminal comprises an audio preprocessing module, a modulation and driving module and a coarse-fine composite light beam alignment module; the receiving earphone comprises an optical receiving module, a posture sensing and aligning module, a signal processing module and a bone conduction audio output unit. According to the system, through a dynamic attitude compensation and light beam alignment mechanism, the audio transmission rate greater than or equal to 1Mbps in a 10-meter range is realized, the error rate is less than or equal to 1 * 10 <-6 >, and the transmission delay is less than 50ms. The method has the advantages of high communication quality, strong anti-interference capability, good wearable performance and the like, and is suitable for scenes of underwater training, voice guidance, immersive audio playing and the like.

The invention discloses a reinforcement learning routing optimization method considering a dynamic underwater sound environment and node mobility. The method comprises the following steps: performing parameter initialization on an underwater sensor network; monitoring and updating underwater environment parameters and node positions in real time, and dynamically updating a network topology connection state; during data transmission, constructing a multi-dimensional state vector, selecting a routing action by adopting an epsilon-greedy strategy, and generating a routing decision; if the data packet transmission fails when the routing action is executed, ending the iteration, otherwise, calculating a multi-target reward value; updating the Q value table to optimize the routing decision; and monitoring network performance indexes in real time, adaptively adjusting reinforcement learning parameters of the intelligent agent for next iteration, and outputting an adaptive routing selection model until an iteration termination condition is met. According to the method, time-varying channel and node mobility challenges can be intelligently dealt with, and multi-objective optimization balance of energy consumption, delay and stability is realized while the data delivery rate is remarkably improved.

The invention relates to the technical field of communication, in particular to a high-precision measurement method for radial velocity of a shallow sea underwater acoustic target based on ray sound field reconstruction, which comprises the following steps of: establishing a three-path propagation model comprising direct arrival, water surface reflection and seabed reflection, and constructing a joint representation equation comprising channel impulse response and target motion parameters by the path propagation model; according to the method, a space-time joint representation model of multipath sound rays is constructed, and the limitation of a traditional single-path model is broken through by quantifying the coupling relation between propagation time delay and Doppler frequency shift of different paths; the development provides a new technical means for underwater target tracking and positioning, underwater acoustic communication Doppler compensation and marine environment dynamic monitoring, and especially has an important application prospect in the fields of underwater unmanned cluster collaboration and the like.

The invention discloses an anti-interference underwater acoustic channel estimation method and device based on model data dual drive, and the method comprises the steps: obtaining an interference data set, and training a neural network; preprocessing the underwater acoustic signal to obtain a pilot frequency part signal, and initializing a channel, an interference sample, a sampling moment and a channel precedence variance gamma; respectively obtaining interference and channel prior scores at the t'moment by using a neural network and an analytical model; the logarithmic likelihood function obtains a gradient about interference and channel conjugation to obtain interference and channel condition scores, and the prior and condition scores are weighted and summed to obtain interference and channel posterior scores; the channel samples and the interference samples are corrected through annealing sampling, gamma is updated, and the posterior score is calculated again; a channel sample and an interference sample at the t'moment are obtained through the inverse process of the diffusion model; and if t'reaches tmin, outputting a final estimated value, otherwise, updating gamma according to the channel sample at the t 'moment, and circulating. According to the invention, accurate estimation of the single carrier communication channel in the structured interference environment is realized.

The invention discloses an ultra-short baseline positioning method based on a binary short baseline, and belongs to the technical field of underwater acoustic target navigation positioning. The method comprises the following steps: S1, designing a spread spectrum underwater acoustic communication signal for underwater acoustic communication between an ultra-short baseline transceiver and a transponder; s2, solving ultra-short baseline time delay information by adopting a frequency domain correlation method, and obtaining high-precision time delay information through an interpolation method; s3, two sets of transceivers with known positions are installed at the ship end at a preset interval distance, and the two sets of transceivers form a binary short baseline framework; installing at least one group of transponders at the mobile terminal, and obtaining the distance information of the two groups of transceivers and the transponders and the initial position information of the mobile terminal; and S4, based on the two groups of distance information and the initial position information, performing binary short baseline positioning calculation by adopting an iterative optimization algorithm to obtain high-precision position information of the mobile terminal. The ultra-short baseline positioning method based on the binary short baseline is high in positioning precision and high in stability, and can still realize high-precision target positioning in a low signal-to-noise ratio environment.

The invention discloses an underwater sound double-expansion channel parameter estimation method based on Newton orthogonal matching pursuit. The method comprises the following steps: firstly, realizing frame synchronization by using a cross-correlation peak of an LFM signal and a received signal; a coarse estimation value of a Doppler coefficient is obtained on a discrete time frequency grid through an ambiguity function method by utilizing the self-correlation characteristic of m-sequence pilot frequency, multipath time delay of a channel is detected by utilizing a matched filtering peak value of a signal after frequency offset compensation, and a coarse estimation result of the channel is obtained; executing Newton iteration optimization in a continuous parameter space by adopting a Newton orthogonal matching pursuit algorithm to realize super-resolution off-grid estimation of the Doppler coefficient of the first data block; and finally, proposing an iterative block tracking strategy, initializing the compensation of the rear block through the estimated value of the front block, and updating the time-varying Doppler coefficient by using the balanced signal feedback to realize the dynamic tracking of the time-varying Doppler coefficient. According to the invention, the Doppler estimation root-mean-square error is obviously reduced, and the calculation efficiency is high.

A system that performs beam selection and beam merging using beam-specific signal quality metrics corresponding to a minimum noise floor. For example, a device may track a minimum noise floor for each beam, determine a highest minimum noise floor across the beams, and determine a noise floor ratio between the beam-specific minimum noise floor and the highest minimum noise floor. Using a combination of the noise floor ratio and signal-to-noise ratio (SNR) values, the device may perform beam selection by prioritizing low background noise as well as high SNR to select a pre-defined beam group. In addition, the device may use the noise floor ratio to perform beam merging and generate single-channel output audio data using the selected beam group. For example, the device may scale the beams based on a combination of the SNR value and the noise floor ratio.

Methods are generally described for inaudible orthogonal signal communication. An example method includes determining, based on an input message, a series of symbols, where each symbol from the series of symbols represents a numerical value, wherein each symbol from the series of symbols corresponds to a band-limited white noise tone orthogonal to each other band-limited white noise tone corresponding to each other symbol. The example method also includes generating a sub-token comprising each symbol from the series of symbols, where each symbol overlaps in time with at least one other symbol. The example method also includes modulating a carrier wave with the sub-token to produce a signal audio waveform, where the modulation uses a spread spectrum technique, and providing the signal audio waveform to a television device, where the television emits the signal audio waveform as a low-amplitude audio signal.

The invention discloses an underwater acoustic image transmission method combining feature extraction and semantic compression, which relates to the technical field of data transmission, and comprises the following steps: a sending end performs semantic feature extraction on an original underwater acoustic image to obtain a semantic feature set; performing compressed encoding on the semantic feature set to generate compressed semantic data; transmitting the compressed semantic data to a receiving end through an underwater acoustic channel; and the receiving end decodes the received compressed semantic data, restores the semantic feature set, and performs image reconstruction and / or task identification based on the semantic feature set. The method comprises the following steps: performing semantic feature extraction on an underwater acoustic image through a sending end, and converting pixel data into a semantic feature set; the data volume is significantly reduced through compression coding, so that the method adapts to the limited bandwidth of an underwater acoustic channel; and the receiving end performs image reconstruction or direct task identification based on the restored semantic features. According to the method, efficient and reliable transmission of image data in a low-bandwidth and high-packet-loss underwater acoustic environment is realized, and effective maintenance and task availability of semantic information are ensured.

The invention discloses a multi-carrier underwater acoustic communication channel estimation method under time delay-scale double extension, and aims to solve the problems that a common multi-carrier underwater acoustic channel model cannot depict the influence of a Doppler effect and a traditional channel estimation method is limited in precision. A time delay-scale double-extension channel model is used to describe the influence of the Doppler effect on a multi-carrier underwater acoustic communication system, an orthogonal matching pursuit algorithm is used to separate multipath signals, and a Newton method is combined to correct the delay and size parameter estimation result of each path of a channel. And the algorithm complexity is reduced while off-grid channel estimation is realized. The depiction of the Doppler effect is more in line with a real scene, and the off-grid channel estimation and low algorithm complexity are realized, so that the channel estimation result is more accurate.

The invention relates to the technical field of deep sea communication and ocean observation, in particular to a long-term stable real-time communication system based on domestic satellites under high sea conditions. Comprising a submerged buoy body, the submerged buoy body is provided with a communication floating body module, a multi-source domestic satellite communication module, a low-power-consumption control module and a data processing module which are electrically connected in sequence, and an intelligent sensing module and an underwater data access module which are respectively connected with the data processing module; the device further comprises a main floating body. The system can be widely applied to deep-sea subsurface buoy platforms, marine environment monitoring stations, deep-sea scientific investigation equipment and other scenes, realizes real-time transmission of hydrodynamic and biogeochemical multi-element synchronous observation data at the water depth of 0-6000 meters, and supports research on the dynamic process of isolated waves, near-inertia internal waves and the like in the ocean and safety guarantee of the marine environment.

A device may include a processor, a receiver, and a transmitter. The receiver may be configured to receive a content signal. The transmitter may be configured to transmit the content signal. The transmitter may be configured to transmit an associated inaudible signal. The content signal, the associated inaudible signal, or both, may be transmitted to one or more electronic devices. Each of the one or more electronic devices may be configured with audio interfaces. The receiver may be configured to receive a respective message from each of the one or more electronic devices. Each respective message may be based on the associated inaudible signal. Each respective message may include a respective electronic device identifier. The transmitter may be configured to transmit one of the respective messages.

The present disclosure provides a cleaning robot comprising one or more motors and a controller configured to control the one or more motors to generate acoustic signals indicative of content. The controller is configured to control at least one of a frequency of the acoustic signals and a pulse width of acoustic pulses generated by the one or more motors. The controller may be configured to control the one or more motors to generate an ascending sequence of frequencies and to use a frequency of a pulse generated by the one or more motors to validate a pulse width of the pulse. The one or more motors are configured to transmit frequency tones that indicate bits of a first value within the content. The one or more motors comprise at least one of a pump motor and a drive motor, wherein the controller is configured to control electric power within a motor coil using pulse width modulation to generate the acoustic signals.

The invention relates to an underwater sonar signal enhancement method based on an RLS adaptive filter. The method comprises the following steps: S1, receiving an original sonar signal through an RLS adaptive filter module and executing real-time filtering processing; s2, acquiring underwater environment parameters by using an environment sensing module, and generating an environment feature vector; s3, dynamically adjusting a forgetting factor lambda and an initial covariance matrix P (0) of an RLS adaptive filter module through a parameter feedback adjustment module according to the environment feature vector; and S4, updating the weight of the RLS adaptive filter module by using the adjusted parameters, performing residual noise processing on the filtered signal, and outputting an enhanced signal. According to the invention, by introducing a feedback adjustment mechanism based on environmental perception data, dynamic optimization of key parameters of the RLS algorithm is realized, so that the signal enhancement capability and stability of an underwater communication system in a complex environment are improved.

The invention relates to the technical field of covert communication, in particular to a bionic covert communication method based on multi-sea-area dolphin voiceprint feature library matching, which comprises the following steps of: constructing a dynamic voiceprint feature library associated with sea area coordinates, dolphin species and voiceprints, and adjusting acoustic parameters in combination with real-time environment monitoring; communication information is encoded in a natural variation range of acoustic characteristics of the dolphin, bionic signals highly conforming to the sound scene of a target sea area are synthesized and emitted, low-recognizable and low-monitorable hidden data transmission between underwater equipment is achieved, meanwhile, false alarm of a marine mammal protection system is avoided, and the safety communication requirement of equipment such as an unmanned underwater vehicle is met.