Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

1776 results about "Doppler frequency" patented technology

Rail transit operation and maintenance state data processing method and system based on artificial intelligence

The invention discloses a rail transit operation and maintenance state data processing method and system based on artificial intelligence, particularly relates to the technical field of rail operation and maintenance management, and is used for solving the problem that the potential multipath effect degree of a tunnel area of rail transit cannot be found in advance in the prior art. A tunnel area is divided into a complex area and a common area, when a train is located in the common area, delay diffusion caused by a complex reflection path and spectrum expansion caused by dynamic Doppler frequency shift are evaluated by analyzing a high-precision channel impulse response estimation result and signal time-varying spectrum characteristics, and whether signal transmission is normal or not is judged; in a complex area, whether the tunnel curvature and the cross structure cause signal shielding and sudden fading or not is judged firstly, and if not, signal distortion caused by electromagnetic resonance is evaluated by analyzing high-order statistical characteristics. Finally, the signal delay diffusion degree and the electromagnetic resonance distortion degree are comprehensively analyzed, and the potential risk of signal transmission is evaluated.
Owner:GUANGDONG HUANENG ELECTROMECHANICAL GRP CO LTD

Multi-satellite network converged communication link optimization and anti-interference method

The invention discloses a multi-satellite network converged communication link optimization and anti-interference method, which belongs to the technical field of wireless communication networks, and comprises the following steps: acquiring Doppler frequency shift parameters of satellite nodes, adjacent satellite radiation quantity parameters and preset geographical shielding coefficients, and generating a link dynamic quality coefficient; constructing a dynamic topological graph according to the link dynamic quality coefficient; performing radio frequency fingerprint extraction and frequency domain waveform phase reversal processing on the detected interference signal to generate an anti-interference compensation signal; and when the link dynamic quality coefficient is greater than or equal to a preset quality threshold value, selecting a target transmission path according to the dynamic topological graph, and injecting the anti-interference compensation signal into the target transmission path. According to the invention, a mechanism of cooperation of dynamic link quality evaluation, interference fingerprint feature matching and multi-path fragmentation transmission is adopted, and real-time optimization selection of communication paths, accurate suppression of interference signals and efficient distribution of network resources can be realized in a complex air and space environment.
Owner:JIANGSU ANRUIXUN INFORMATION TECH CO LTD

Anti-deception-interference joint detection method and system based on space-time frequency

The invention relates to an anti-deception-interference joint detection method and system based on space-time frequency, and the method comprises the steps: obtaining a signal source direction of a received satellite signal, and dividing the signal source direction into channels according to angles based on a beam forming criterion; based on a preset capture rule, initiating capture search for the signal in each channel, and synchronously performing correlation peak detection and array antenna anti-interference detection on the signal to obtain angle information of the signal in each channel and satellite PRN information in the capture process; null processing is carried out on the signal source directions of two or more satellite signals appearing at the same angle; outputting a capture result based on the capture rule, and tracking the capture result conforming to the capture rule; doppler frequency shift consistency detection and signal power calculation are carried out on the signals subjected to rotation tracking, and deception signals are recognized and fed back to the antenna array for filtering processing. The application has the effects of expanding the application range of the anti-deception jamming detection method and improving the anti-jamming capability of navigation positioning.
Owner:CHANGSHA HAIGE BEIDOU INFORMATION TECH CO LTD

Low-orbit communication satellite Doppler positioning method and device based on factor graph optimization

The invention relates to a low-orbit communication satellite Doppler positioning method and device based on factor graph optimization. The method comprises the following steps: after required observation data is received and an initial state value of a ground receiver is solved, a factor graph framework is introduced to set a priori factor, a Doppler frequency shift factor, a state constraint factor and a state variable consisting of a three-dimensional position and frequency drift of the receiver according to a Doppler positioning observation model; and constructing a Doppler positioning factor graph model by taking the factors and variables as nodes, introducing a sliding window mechanism to update a factor graph in a factor graph optimization solution process, and solving state variables by adopting a Gaussian-Newton algorithm to finally obtain a Doppler positioning result. According to the method, factor graph modeling is carried out on the Doppler positioning observation model, the advantages of nonlinear modeling, global optimization and capability of fully utilizing historical observation of a factor graph optimization method are exerted, and a relatively small positioning error and a higher convergence speed can be obtained.
Owner:HUNAN ZHONGSEN COMM CO LTD

Missile-borne synthetic aperture radar sea surface moving target space-variant self-focusing imaging method

The invention discloses a space-variant self-focusing imaging method for a missile-borne synthetic aperture radar sea surface moving target. The method comprises the following steps: acquiring a radar fundamental frequency echo signal; performing range pulse pressure and range migration correction on the radar fundamental frequency echo signal to obtain a correction signal, and further obtaining a coarse focusing radar image; extracting a single defocusing target image in the coarse focusing radar image, and inverting the single defocusing target image to an echo data domain to obtain data of single target energy; performing correction to obtain data after correction of the residual range walk; selecting a part of distance units from the data after the residual range walk is corrected, performing Doppler frequency modulation rate estimation on the selected part of distance units by adopting fractional Fourier transform, fitting the estimated Doppler frequency modulation rate by adopting a space-variant phase error model, and constructing a space-variant phase error compensation function of the target; and compensating the data after the correction of the residual range walk, and imaging. According to the invention, the refocusing effect of the moving ship target can be improved.
Owner:XIDIAN UNIV

Unmanned aerial vehicle autonomous decision reinforcement learning method, system and device based on multi-objective optimization, and storage medium

The invention relates to the technical field of unmanned aerial vehicle autonomous decision, provides an unmanned aerial vehicle autonomous decision reinforcement learning method, system and device based on multi-objective optimization, and a storage medium, and solves the problems of limited dynamic task distribution capability and poor decision capability of an unmanned aerial vehicle. The method comprises the steps that based on infrared data and radar data, a moving track prediction sequence of a suspicious target in a target area is generated, a moving probability thermodynamic diagram is constructed, and the target area comprises a patrolled area; performing Doppler frequency shift analysis on the radar data to generate a target velocity vector field; and in combination with the position data of the unmanned aerial vehicle, outputting an unmanned aerial vehicle autonomous decision reinforcement learning result of a dynamic segmentation scheme containing an unpatrolled region through a region re-division reinforcement learning model based on a reward function for multi-objective optimization. The reward function is used for reflecting area coverage rate maximization, target tracking success probability maximization and path energy consumption minimization. According to the invention, autonomous intelligent decision-making of the unmanned aerial vehicle on the unpatrolled area is realized.
Owner:ZHUHAI XIANG YI AVIATION TECH CO LTD

Method and system for intelligently sealing and testing wafer in semiconductor chip

The invention discloses an intelligent sealing test method and system for a wafer in a semiconductor chip, and relates to the technical field of semiconductor manufacturing, and the method comprises the steps: initializing a magneto-electric field cooperation parameter, optimizing the magneto-electric field cooperation parameter through a multi-target genetic algorithm, and driving core-shell nanoparticles to carry out the metallization filling of a high-precision through hole wafer, generating a wafer with a metalized through hole structure; based on the metalized through hole structure wafer, bonding parameters are generated through a laser Doppler frequency vibration spectrum analysis method, flip interconnection is achieved through a thermal ultrasonic virtual process, and a low-defect bonding wafer is generated; a finite element inversion algorithm is adopted, a stress distribution map of a bonding interface is established, an anti-thermal-stress packaging layer is constructed through an intelligent stress matching algorithm, and the low-defect bonding wafer is packaged; and through a multi-target genetic algorithm, magnetoelectric field cooperation parameters are optimized, core-shell nano-particles are driven to directionally deposit, and accurate control over the metallization filling process is achieved.
Owner:弘润半导体(苏州)有限公司

Delay-doppler domain channel estimation and frame synchronization

The present disclosure provides a wireless receiver having a Delay Doppler channel detector. The Delay Doppler channel detector includes a Delay Dopper domain channel estimator and a detector and demodulator. The Delay Doppler domain channel estimator is configured for estimating a channel gain, a delay, and a Doppler frequency shift of a path of a channel of data received via the channel. The detector and demodulator is configured for extracting a symbol sequence of the received data based on the estimated channel gain, the estimated delay, and the estimated Doppler frequency shift of the path of the channel.
Owner:NEWSOUTH INNOVATIONS PTY LTD

Wind and wave response modeling and ocean current inversion method based on machine learning

A wind and wave response modeling and ocean current inversion method based on machine learning relates to the technical field of artificial intelligence and ocean information services, and comprises the following steps: (1) data acquisition; (2) data processing; (3) constructing a data set; (4) establishing a sea surface flow velocity inversion model by using a particle swarm optimization machine learning algorithm; and (5) obtaining an optimal sea surface flow velocity inversion model through testing and case analysis. Aiming at ocean and Doppler frequency shift characteristics of the sea surface, the invention provides a particle swarm optimization XGBoost model wind wave Doppler contribution prediction method for the first time, and the wind wave Doppler contribution estimation precision and speed can be effectively improved.
Owner:CHINA UNIV OF PETROLEUM (EAST CHINA) +2

Laser radar test method based on long-distance target distance measurement result

The invention discloses a laser radar test method based on a long-distance target distance measurement result, and the method comprises the following steps: obtaining a laser radar echo signal, and extracting the frequency spectrum information of the echo signal; doppler frequency shift characteristic parameters are extracted according to the frequency spectrum information, and the relative speed of the target is calculated based on a preset frequency shift calculation model; acquiring multi-source sensor data associated with the laser radar test platform, and fusing to construct a dynamic ranging reference coordinate system; performing dynamic motion compensation on a laser ranging result according to the relative speed of the target to obtain a target initial measurement distance after Doppler correction; mapping the target initial measurement distance after Doppler correction to the dynamic distance measurement reference coordinate system to obtain a remote target final distance measurement result aligned with a test platform coordinate system; and outputting the accurate position and moving state information of the target in the three-dimensional space according to the final distance measurement result. According to the invention, the ranging precision and stability can be improved.
Owner:中国人民解放军陆军装备部驻南京地区军事代表局驻南京地区第四军事代表室

Underwater ultrasonic Doppler real-time analysis method and device based on digital transducer

The invention provides an underwater ultrasonic Doppler real-time analysis method and device based on a digital transducer, and relates to the technical field of data analys.The method comprises the steps that 1, multiple beams of directional ultrasonic waves are emitted into drilling fluid through a digital transducer array on the outer wall of a marine riser, echo signals reflected by gas-liquid two-phase flow are received, and the digital transducer array is used for receiving the echo signals; performing real-time digital conversion on the echo signal to generate an original digital signal containing phase and amplitude information; 2, Doppler frequency shift feature extraction is conducted on the original digital signals, and the real-time movement speed and direction of bubbles in the drilling fluid are determined by calculating the frequency deviation of reflected ultrasonic waves and transmitted ultrasonic waves. Through the digital transducer array and the ultrasonic Doppler technology, accurate measurement of motion parameters of bubbles in drilling fluid, real-time calculation of local gas content and early warning and grading response of gas cut are achieved, and the safety and the intelligent level of drilling operation are improved.
Owner:福建澳泰自动化设备有限公司 +1

GNSS real-time deception jamming detection method and system based on deep learning

The invention discloses a GNSS real-time deception jamming detection method and system based on deep learning, and belongs to the field of satellite navigation signal processing, and the method comprises the steps: collecting Doppler frequency shift signals of a GNSS receiver in real time, and obtaining an initial training data set; an LSTM prediction model with an incremental learning mechanism is constructed, the LSTM prediction model comprises a double-layer LSTM network and a full connection layer, a gating mechanism is introduced into the double-layer LSTM network, and the initial training data set is adopted to add Gaussian white noise to the prediction model for model training; performing sliding window processing on the initial training data set, and extracting a multi-dimensional feature vector; inputting the trained prediction model for prediction to obtain a model prediction value; calculating a residual error between a model predicted value and a real value, calculating a standard deviation of the residual error after eliminating a preheating period, and dynamically setting a threshold value based on the standard deviation of the residual error; and when the absolute value of the residual exceeds a threshold value and the sampling point processed by the sliding window is located in a preset interference time window, judging that a signal interference event occurs.
Owner:NAT TIME SERVICE CENT CHINESE ACAD OF SCI

Rapid radar scattering test method based on polarization decomposition

The invention belongs to the technical field of radar signal processing, and discloses a radar scattering rapid test method based on polarization decomposition. Comprising the following steps: scanning a target 3D model, simulating scattered field distribution in different incident angles and polarization modes, calculating polarization contrast, and identifying a polarization sensitive area; establishing a dynamic coordinate system conversion model, fusing RTK data, IMU data and laser tracking data, and correcting the position of the trolley and the model in combination with a Doppler frequency shift model and a least square method; calculating an optimal test path of the trolley according to the sensitive area by adopting a natural heuristic optimization algorithm; establishing a geometric environment model, obtaining a back scattering signal through beam forming, analyzing a polarization coherence matrix, obtaining a high-entropy region, and decomposing scattering components; according to the method, closed-loop optimization is formed from a data acquisition source to a scattering component analysis tail end, and the test efficiency and the real-time performance are remarkably improved.
Owner:SHIJIAZHUANG SHILIANDA TECH

Cross-scene wireless gesture recognition method based on unsupervised learning

The invention discloses a cross-scene wireless gesture recognition method based on unsupervised learning, and the method comprises the steps: obtaining Doppler frequency shift data, and carrying out the preprocessing of the Doppler frequency shift data; inputting the preprocessed data into a shared feature extractor, and mapping the extracted features to the same hidden space through an adversarial auto-encoder; pseudo marks are distributed through classification prediction in the preheating stage, and distribution of the pseudo marks is perfected through a target-oriented centroid point after the preheating stage; constructing target-oriented multivariate normal distribution through all pseudo marks, and migrating a source domain to a target domain on a hidden space level in a bias adding mode to obtain a trained cross-scene wireless gesture recognition model; and analyzing a newly input target domain sample through the trained cross-scene wireless gesture recognition model, and predicting a gesture corresponding to the target domain sample in an unmarked manner. According to the method, the problem of difficulty in sensing data marking can be relieved, and stable and high-performance gesture recognition can be realized in different scenes.
Owner:SHENZHEN UNIV

Frequency offset estimation method and device based on 5G demodulation reference signal

ActiveCN119420610AFollow up in timeCarrier regulationAlgorithmPhysical layer
The invention provides a frequency offset estimation method and device based on a 5G demodulation reference signal, and the method comprises the steps: determining a first frequency offset estimation value set according to a frequency domain receiving sequence and a local sequence of a DMRS symbol configured by a physical layer channel; eliminating frequency offset estimation values with absolute values greater than a preset threshold value in the first frequency offset estimation value set to obtain a second frequency offset estimation value set; performing frequency offset compensation on the DMRS symbol by using each frequency offset estimation value in a second frequency offset estimation value set to obtain a frequency offset compensation sequence of each frequency offset estimation value on the DMRS symbol; and performing correlation operation on the frequency offset compensation sequence of the DMRS symbols and the local sequence of the DMRS symbols by the frequency offset estimation values to obtain correlation values, and taking the frequency offset estimation value corresponding to the maximum correlation value as a frequency offset estimation result. The method effectively improves the frequency offset estimation range, enables the system to support larger Doppler frequency offset tracking and compensation, and further supports larger relative movement speed of a receiving end and a transmitting end.
Owner:GUANGZHOU HAIGE COMMUNICATION GROUP INCORPORATED COMPANY

Joint estimation method for timing advance and carrier frequency offset based on conjugate symmetric ZC sequence

The invention discloses a joint estimation method for timing advance and frequency offset based on a conjugate symmetric ZC sequence, which relates to the technical field of wireless communication and comprises the following steps of: inputting a leader sequence extracted from a demodulated received signal; two ZC sequences in the leader sequence are respectively in cross-correlation with a local ZC sequence, and a peak value of a cross-correlation result amplitude is obtained; iteratively performing fractional frequency offset compensation estimation to obtain a fractional frequency offset estimation value and a compensated leader sequence; performing timing advance estimation and integer frequency offset estimation to obtain a timing advance estimator and an integer frequency offset estimator; obtaining a frequency offset estimation value by combining the decimal multiple and integer multiple frequency offset estimation values; and ending the timing advance and frequency offset estimation, and outputting estimated values of the timing advance and the frequency offset. According to the method, the negative influence of the decimal frequency offset on the ZC sequence is eliminated in a mode of iteratively compensating and estimating the decimal frequency offset, and high-performance timing advance and frequency offset joint estimation with robustness to frequency shift and noise is realized based on the structure of the conjugate symmetric ZC sequence; the method is suitable for a non-ground network communication scene with large Doppler frequency shift and low receiving signal-to-noise ratio.
Owner:SUN YAT SEN UNIV

Radar apparatus, radar signal generating apparatus, and radar signal generating method

A radar apparatus includes: a plurality of transmission antennas including a first transmission antenna forming a first beam and a second transmission antenna forming a second beam different from the first beam; and transmission circuitry, which, in operation, performs multiplexing transmission of a transmission signal from the plurality of transmission antennas, the transmission signal being a signal to which a phase rotation corresponding to a Doppler shift amount assigned to each of the plurality of transmission antennas has been applied. In the radar apparatus, a Doppler shift interval by the plurality of transmission antennas is uneven on a Doppler frequency axis, and a first pattern of the Doppler shift amount assigned to the first transmission antenna is different from a second pattern of the Doppler shift amount assigned to the second transmission antenna.
Owner:PANASONIC AUTOMOTIVE SYST CO LTD

Simulation test system and method suitable for radiation type semi-physical radar

The invention discloses a simulation test system and method suitable for a radiation type semi-physical radar. The system comprises a semi-physical radar; the three-axis turntable is configured to complete radar antenna motion attitude simulation; the scene visualization and simulation control computer is configured to complete scene planning, deduce a simulation process, distribute a scene situation and calculate target space data; the radar echo simulator is configured to perform time delay, Doppler frequency shift and amplitude modulation on a radar emission radio frequency signal through the FPGA and output a target echo simulation radio frequency signal; the antenna array and feed subsystem performs rough simulation and accurate simulation of a target position, converts a target echo radio frequency signal into an electromagnetic signal and radiates the electromagnetic signal to the space; the test evaluation computer is configured to calculate and display an evaluation index. According to the invention, a real radar is connected to a simulation closed loop, and a plurality of targets and movement thereof can be simulated for the radar according to scene driving, so that the semi-physical radar is fully simulated and tested.
Owner:10TH RES INST OF CETC

Obstacle detection method and system based on frequency modulated continuous wave laser radar

The invention relates to the technical field of laser radars, in particular to an obstacle detection method and system based on a frequency-modulated continuous wave laser radar, and the method comprises the steps: transmitting a chaotic frequency-modulated continuous wave signal to a detection region, and obtaining a reflection echo signal of a target object; performing decoupling calculation on the difference frequency electric signal to obtain a target time frequency distribution matrix; according to the target time-frequency distribution matrix, predicting the Doppler frequency shift amount of the target object at the next moment; based on the chaos frequency modulation adjustment signal, obtaining a distance measurement deviation compensation amount; the chaos frequency modulation adjustment signal is obtained by dynamically adjusting the chaos frequency modulation slope of the chaos frequency modulation continuous wave signal through the Doppler frequency shift amount; and compensating the difference frequency electric signal frequency value of the target object according to the distance measurement deviation compensation amount and the environmental noise data so as to solve obstacle distance speed detection information. According to the invention, the Doppler frequency shift amount is predicted in real time and the chaotic frequency modulation continuous wave signal parameters are dynamically adjusted, so that the accurate compensation of the distance measurement deviation is realized, and the accuracy of obstacle distance speed detection is improved.
Owner:GUANGDONG OCEAN UNIVERSITY

Life detection radar system with three-dimensional positioning function

PendingCN119861369ARadio wave reradiation/reflectionRadar systemsTarget Motion Analysis
The invention relates to the technical field of radar, and discloses a three-dimensional positioning life detection radar system, and the radar system comprises a phased array antenna unit which is used for transmitting radar waves and dynamically adjusting the wave beam direction according to the target position; the signal receiving unit is used for receiving a radar signal reflected by a target; the Doppler frequency shift analysis module is used for analyzing the frequency change of the received radar signal and extracting a micro-motion signal of the target; the target motion analysis module is used for tracking the motion of the target through a Kalman filtering technology; the three-dimensional reconstruction module is used for reconstructing the three-dimensional position of the target through an electromagnetic field integral equation and multi-source sensor information fusion according to the received signals; and the deep learning module is used for identifying the micro-motion signal and optimizing target classification. By adopting the phased-array antenna unit and the beam forming technology, the technical effects of carrying out accurate three-dimensional scanning and rapid dynamic beam adjustment on the target are achieved.
Owner:BEIJING SOBOLA AUTOMATION TECH CO LTD

SER6 Pro antenna with adaptive beam forming capability

The invention discloses an SER6 Pro antenna with adaptive beam forming capability, comprising: a generation module for generating an initial beam directional diagram based on spatial-temporal correlation analysis of multipath signals; the calculation module is used for updating beam direction parameters in real time by using a Doppler frequency shift estimation algorithm so as to adapt to Doppler frequency shift change of a high-speed mobile user; the suppression module is used for carrying out noise suppression on the beam signal in a frequency domain by adopting an adaptive filter; and the optimization module is used for dynamically adjusting the beam forming matrix and optimizing the beam direction and intensity through an iterative optimization algorithm. The method has the beneficial effects that the problem of inaccurate beam direction identification caused by excessive reflected and scattered signals in a complex multi-path propagation environment is solved; the problem of unstable beam tracking caused by significant change of Doppler frequency shift in a high-speed mobile user scene is solved; and the problem that the signal-to-noise ratio is reduced due to the strong external noise source in a high-interference environment is solved.
Owner:SHENZHEN TIANWEIXUN WIRELESS TECH CO LTD

Inter-Doppler interference suppression method based on Gaussian learning factor particle swarm optimization

The invention discloses an inter-Doppler interference suppression method based on a Gaussian learning factor particle swarm algorithm. The inter-Doppler interference suppression method comprises the following steps that pilot frequency and data symbols are coded to a resource grid of a two-dimensional time delay Doppler domain through orthogonal time-frequency space modulation; on a transmitter, mapping data on a time delay Doppler domain grid to a time-frequency domain through inverse symplectic finite Fourier transform to obtain a time-frequency domain signal; performing Hisenberg transformation on the time-frequency domain signal to obtain a time domain sending signal; obtaining a time domain receiving signal after the time domain sending signal passes through a wireless channel; performing Doppler compensation processing on the time domain receiving signal by using Doppler frequency shift to obtain a signal after Doppler compensation; then performing matched filtering on the signal after Doppler compensation and a received pulse, and sampling to obtain a matched filter output signal; and the matched filter output signal is subjected to the Sextile Fourier transform to obtain a time delay Doppler receiving signal. The method can realize suppression of inter-Doppler interference to a certain extent.
Owner:SHAANXI HONGYI TECHNOLOGY CO LTD

Markov chain Monte Carlo-based sparse Bayesian parameter estimation method

The invention discloses a sparse Bayesian parameter estimation method based on a Markov chain Monte Carlo (MCMC). The sparse Bayesian parameter estimation method is suitable for super-resolution target number detection and high-precision target parameter estimation in a communication perception integration (ISAC) scene. The method comprises the following steps: a base station transmits an orthogonal frequency division multiplexing (OFDM) signal and receives a target reflection echo; performing frequency domain transformation on the echo signal and constructing a high-dimensional observation vector; target parameters are modeled as random variables including path complex gain, time delay, Doppler frequency shift and angle, and a learnable parameterized sensing matrix is constructed; the sparse Bayesian framework is combined with MCMC sampling, the parameters are iteratively updated through random small-batch gradient optimization and the Metropolis-Hastings criterion, and finally the estimation result of the target parameters is output. According to the method, the precision limitation of a traditional gridding method is broken through, super-resolution parameter estimation is achieved, meanwhile, the calculation complexity and the storage overhead are remarkably reduced, and the method is suitable for the high-precision sensing requirement in a 6G communication system.
Owner:SOUTHEAST UNIV

Emergency communication method and system based on multi-mode early warning broadcast terminal

The invention provides an emergency communication method and system based on a multi-mode early warning broadcast terminal. Wherein the early warning function of the multi-modal terminal is activated and a dynamic feature library is constructed by defining disaster triggering conditions of combination of soil humidity and rainfall intensity; periodically scanning surface micro-deformation by using a radar array, calculating a mountain displacement rate in combination with Doppler frequency shift measurement, and generating a terrain risk thermodynamic diagram; a low-power-consumption long-distance wireless netlike self-organizing communication link is constructed, multi-hop redundancy transmission is started when a public network is interrupted, and an early warning data packet is segmented and forwarded; according to the early warning level cooperatively judged by the dynamic feature library and the radar array, the forwarding priority of the data packet is dynamically allocated, synchronous matching of an acousto-optic early warning signal and a disaster risk gradient is realized, and a hierarchical response link for linkage of terrain deformation monitoring and emergency communication is formed. According to the technical scheme provided by the invention, the emergency response efficiency and the coverage range are improved.
Owner:BEIJING CASRS INFORMATION TECH

Double-base ISAC clock synchronization algorithm design and system based on LoS reference path

The invention belongs to the technical field of unmanned aerial vehicle communication perception integration, discloses a double-base ISAC clock synchronization algorithm design and system based on an LoS reference diameter, and aims to solve the problem of measurement errors caused by clock asynchronization of a transmitting end and a receiving end. And a receiving end receives a communication signal based on an LoS path and a sensing signal based on a non-line-of-sight (NLoS) path through a communication and sensing integrated design. The invention provides a clock synchronization algorithm based on LoS reference path assistance, and the time delay and Doppler frequency of the signal are measured by using the propagation characteristics of the LoS signal, so that the clock skew and Doppler frequency skew are accurately estimated. According to the algorithm, communication and sensing signals are combined, the clock skew of the receiving end is dynamically adjusted and compensated, asynchronous error accumulation is reduced, and sensing precision and system performance are remarkably improved. Simulation results show that the method effectively enhances communication and sensing functions of the system in application scenarios such as low-altitude economy.
Owner:YANGTZE DELTA REGION INST (QUZHOU) UNIV OF ELECTRONIC SCI & TECH OF CHINA

SAR (Synthetic Aperture Radar) sea surface flow velocity inversion method based on physical guidance and data driving fusion

The invention discloses an SAR sea surface flow velocity inversion method based on physical guidance and data driving fusion, and relates to the field of flow velocity inversion, and the method comprises the steps: carrying out the non-geophysical Doppler frequency shift correction of the Doppler frequency shift observed by a spaceborne synthetic aperture radar, and obtaining the geophysical Doppler frequency shift; predicting based on a wave-induced Doppler frequency shift model according to a radar incident angle, reanalyzed wind direction data, a sea surface 10-meter height wind speed inverted by an SAR (Synthetic Aperture Radar), a simulated wind wave parameter, a simulated surge parameter and a simulated maximum wave parameter to obtain a wave-induced Doppler frequency shift; the wave-induced Doppler frequency shift model is obtained based on physical guidance and data-driven modeling; doppler frequency shift generated by sea surface flow is determined according to the geophysical Doppler frequency shift and the wave-induced Doppler frequency shift; according to the method, the Doppler frequency shift generated based on the sea surface flow is converted to obtain the sea surface radial flow velocity, the wave-induced Doppler frequency shift is accurately removed, and reliable inversion of the sea surface flow velocity is realized.
Owner:SANYA MARINE LAB

Rayleigh wind lidar frequency discrimination method and system

The invention belongs to the technical field of laser radars, and particularly relates to a Rayleigh wind measurement laser radar frequency discrimination method and system. The frequency discrimination method comprises the following steps: emitting dual-frequency laser to the atmosphere in a time-sharing manner, and receiving an atmosphere echo signal after interaction between the dual-frequency laser and atmospheric molecules; introducing the atmospheric echo signal into an energy detection channel and a Fabry-Perot interferometer channel through a spectroscope; acquiring the signal intensity of the dual-frequency laser passing through the energy detection channel and the signal intensity of the dual-frequency laser passing through a Brillouin-Perot interferometer channel; and the Doppler frequency shift amount is obtained through the signal intensity of the dual-frequency laser after passing through the energy detector channel and the Fabry-Perot interferometer channel. The method has the advantages of being high in implementation performance, capable of reducing cost and complexity and high in optical stability.
Owner:HEFEI INSTITUTE OF PHYSICAL SCIENCE CHINESE ACADEMY OF SCIENCES

Broadband satellite signal blind demodulation reconstruction method and system based on sparse representation

The invention relates to the technical field of satellite communication signal processing, and discloses a broadband satellite signal blind demodulation reconstruction method and system based on sparse representation. The method comprises the following steps: carrying out frequency domain transformation on broadband satellite mixed signals to extract pilot frequency features to construct a beam state feature matrix, inputting the matrix into an adversarial network to generate a beam adaptive sparse dictionary, constructing a topological relation graph according to a Doppler frequency shift set, and carrying out collaborative sparse decomposition to obtain a sparse coefficient matrix; and extracting a code rate candidate set to execute parallel sparse reconstruction, determining an actual code rate through self-consistency verification to obtain a complete signal, analyzing a switching instruction, extracting time sequence statistical characteristics, predicting target domain characteristics, generating a switched sparse dictionary, and executing demodulation. The sparse decomposition precision, the code rate blind estimation accuracy, the cooperative processing efficiency and the switching continuity of the broadband satellite mixed signals are improved.
Owner:TIANJIN RONGXING GRP CO LTD

Frequency discrimination curve calibration system, method and device

The invention discloses a frequency discrimination curve calibration system, method and device. A frequency locking technology is adopted, the output laser frequency of the seed laser is stably locked on an absorption peak of the atom / molecule absorption cell, and the problem of frequency drift of the seed laser is effectively solved. Meanwhile, two acousto-optic modulators are used for implementing accurate out-of-cavity passive frequency modulation on the seed laser, and the laser frequency is moved to a preset zero-speed frequency point of an optical frequency discriminator and a linear working area edge frequency point from an atom / molecule absorption peak position. In the calibration process, the telescope vertically points to the zenith, and atmospheric echoes with zero Doppler frequency shift are provided as reference. At the moment, the optical frequency discriminator measures and records the transmittance of a preset zero-speed frequency point in the center of the linear working area and the transmittance of an edge frequency point, and a new frequency discrimination curve can be derived based on the linear hypothesis of the frequency discrimination curve.
Owner:BEIJING METABTAR RADAR +1

Unmanned aerial vehicle measurement and control signal capturing method, related device and computer storage medium

The invention provides a method for capturing measurement and control signals of an unmanned aerial vehicle, a related device and a computer storage medium, and the method comprises the steps: obtaining the current time in the ephemeris information of a current low-orbit satellite, the distance between the current low-orbit satellite and the unmanned aerial vehicle, the carrier frequency of a transmitted signal, and the light speed; calculating to obtain a predicted value of Doppler frequency offset of the unmanned aerial vehicle measurement and control signal; determining a coarse estimation value of Doppler frequency offset of the unmanned aerial vehicle measurement and control signal according to a sampling result of the unmanned aerial vehicle measurement and control received signal and a prediction error range; correcting the rough estimation value of the Doppler frequency offset of the measurement and control signal of the unmanned aerial vehicle by adopting a Shannon interpolation algorithm to obtain a Doppler frequency offset value of the measurement and control signal of the unmanned aerial vehicle; and finally, carrying out carrier frequency compensation according to the coarse estimation value and the fine estimation value of the Doppler frequency offset of the unmanned aerial vehicle measurement and control signal to obtain a compensated unmanned aerial vehicle measurement and control signal. The method effectively reduces the frequency domain search range, shortens the signal capture time, improves the estimation precision of Doppler frequency offset, and improves the precision of measurement and control signals of an unmanned aerial vehicle.
Owner:AVIC (CHENGDU) UAS CO LTD