218 results about "Signal modeling" patented technology

The invention belongs to the technical field of carrier frequency offset estimation, and particularly relates to a carrier frequency offset estimation method based on Newton orthogonal matching pursuit. The method comprises the following specific steps of: splitting CFO into two parts of frequencies, namely off-grid deviation and grid point frequency, and further modeling an observation signal as a parameter weighted compressed sensing problem; using a Newton orthogonal matching pursuit algorithm to iteratively optimize the off-grid deviation of the CFO and the estimation of the grid point frequency, and obtaining a CFO candidate frequency set; and obtaining a required CFO estimation result from the candidate set by using the lead code information of the target user. According to the method, the complexity requirement of an actual system is met, meanwhile, the precision of CFO estimation is remarkably improved, and good robustness is achieved.

The invention discloses a self-adaptive switching system and method for power supply and distribution, and the system comprises a data collection module, an analysis module, a modeling module, a decision module, an execution module and an early warning module, and the data collection module generates a real-time monitoring signal; the analysis module performs dynamic weighted evaluation according to the real-time monitoring signal and generates an evaluation signal; the modeling module constructs a virtual model of the power supply system and generates an analog signal; the decision signal generates a control signal containing a path selection instruction; the execution module controls the semiconductor device to switch the physical connection state of the power supply according to the control signal and generates a switch feedback signal; and the early warning module forms an equipment health assessment result according to the switch feedback signal and an abnormal arc signal when the execution module switches the connection state and transmits the result to the decision module. The self-adaptive switching system for power supply and distribution can solve the problem that a traditional power supply and distribution switching system depends on a single threshold to judge the state of a power supply and cannot comprehensively evaluate the quality of electric energy.

The invention discloses a power coupling-considered capacity ratio estimation method for a network-constructing / network-following multi-machine hybrid system, and the method comprises the steps: building a GFL-GFM hybrid system model, combining VSG power coupling small signal modeling and a dynamic relative gain matrix (DRGA), and quantifying the coupling strength of active / reactive power to output voltage; the frequency domain impedance characteristic of the GFM converter is simplified, and an ideal voltage source series equivalent reactance equivalent model is constructed; deriving an analytical relationship between a generalized short-circuit ratio (gSCR) and a capacity ratio based on the model, and generating a ratio formula in combination with engineering boundary sub-scenes to form a ratio range suitable for multiple scenes; for coupling time-varying characteristics, a closed-loop mechanism of'mixed mode-coupling sensing-correction calculation-execution feedback 'is constructed, and the ratio is dynamically adjusted. According to the method, coupling quantization and multi-machine coordination control are deeply fused, the problem that the external characteristic model precision and the multi-working-condition adaptability are difficult to consider under complex environment coupling is effectively solved, and the engineering applicability of the hybrid fan system is enhanced.

The invention discloses an impedance remodeling method for suppressing harmonic oscillation based on a superconducting magnetic energy storage system, and belongs to the technical field of power generation, power transformation or power distribution. The method comprises the following steps: analyzing theoretical characteristics of the superconducting magnetic energy storage system, analyzing mathematical models and working characteristics of an SMES and a storage battery, and carrying out theoretical modeling on the hybrid energy storage system; the method comprises the following steps: performing small signal modeling on a grid-connected converter control system under voltage control type virtual synchronous control, and establishing a grid-connected converter small signal sequence impedance model; a sequence impedance remodeling model is introduced, the influence of the sequence impedance remodeling model on the low-frequency impedance of the virtual synchronous control system is revealed, in order to obtain the optimal sequence impedance of the grid-connected converter, real-time and accurate power grid impedance information is obtained by injecting a multi-harmonic disturbance signal into the grid-connected inverter, and a traditional impedance remodeling strategy is dynamically adjusted according to the information. It is ensured that the system still has good stability margin when the power grid impedance fluctuates in a wide range, and the adaptability of the grid-connected inverter under different power grid working conditions is improved.

The invention provides a multi-inverter grid-connected system broadband oscillation suppression method based on impedance collaborative reconstruction, and the method comprises the steps: firstly carrying out the frequency domain small signal modeling, and constructing a station-level system frequency domain impedance model on the basis of a single machine; therefore, the design of an additional control branch is expanded, a power signal is superposed to the control branch through an additional damping control branch so as to realize the improvement of the impedance amplitude of the inverter, and the phase improvement of a capacitive frequency band is realized by adopting an active damping strategy based on a filter; secondly, constructing an impedance collaborative reconstruction method under a multi-inverter system, establishing a two-stage optimization structure, comprehensively solving the position and parameters of a control branch, and achieving the suppression of system oscillation. According to the invention, through collaborative optimization, conflicts of different control strategies are reduced, and the influence of a coupling relationship is minimized; furthermore, through cooperation of the multiple inverters, dual optimization of damping in the space and the frequency domain is achieved, and efficient suppression of broadband oscillation of the multi-inverter grid-connected system is achieved.

The invention discloses a high-frequency shallow water bottom reverberation signal modeling method, and belongs to the technical field of underwater acoustic engineering and signal processing. The method comprises the following steps: setting a modeling hypothesis; a cylindrical array geometric structure is constructed, scattering units are divided, and channel parameters and scattering functions are obtained in combination with a Bellhop tool and a GABIM model; generating a reverberation signal time domain expression, deducing an array receiving signal spatial domain expression and calculating a spatial spectrum; the model can also adjust underwater environment parameters to realize simulation under different conditions, and performs time domain and space domain theoretical analysis on reverberation signals based on a cylindrical array. Multi-dimensional underwater environment parameters are fused, and the modeling precision is improved; a receiving and transmitting combined cylindrical array is adapted, and spatial gain is embodied; experiments prove that the average error is within 3dB, the practicability is outstanding, support can be provided for design and optimization of the sonar system, and the method is suitable for underwater reverberation signal simulation and characteristic analysis of the sonar system in the high-frequency shallow water environment.

The invention discloses an electromagnetic metasurface sparse signal modeling method and device. The method comprises the steps that S1, sparse electromagnetic signals of an electromagnetic metasurface are acquired; s2, solving through signal sparse prior knowledge under the constraint of an electromagnetic constitutive equation to obtain a sparse signal distribution function; s3, according to the sparse signal distribution function, obtaining the coordinate system representation of the sparse signal in the Riemannian manifold space; and S4, according to the coordinate system representation of the sparse signal in the Riemannian manifold space, establishing a signal electromagnetic field manifold embedding model of the sparse signal mapped in the Riemannian space based on the electromagnetic metasurface. By the adoption of the technical scheme, the problems of an existing electromagnetic metasurface sparse signal modeling method in the aspects of algorithm efficiency, model adaptability and hardware collaboration are solved.

The invention discloses an autocorrelation structure analysis method, system and device for underwater sound target recognition, and belongs to the technical field of underwater target recognition, and the autocorrelation structure analysis method comprises the steps: S1, carrying out underwater sound signal modeling based on a sound ray theory; s2, performing autocorrelation analysis to extract a delay inequality structure of the target, so as to classify the multi-path delay structure into a multi-path delay structure A, a multi-path delay structure B and a multi-path delay structure C; and S3, analyzing the depth of the sound source, the receiving depth and the relative distance between the sound source and the receiving depth so as to select one of the multi-path time delay structure A, the multi-path time delay structure B and the multi-path time delay structure C for target identification. The multi-path time delay structures are classified into the multi-path time delay structures A, B and C, and the application conditions of the multi-path time delay structures A, B and C are analyzed, so that subsequent target identification based on the multi-path time delay structures A, B and C is facilitated.

The invention relates to the technical field of satellite navigation signal processing, and discloses a signal noise suppression method in a Beidou navigation system, which comprises the following steps of: performing three-dimensional modeling on navigation signals, and extracting time-frequency characteristics to generate a signal model; constructing an interference heat prediction map, and dynamically updating and identifying a high-interference area; analyzing a signal phase change, calculating a phase rate, and identifying abrupt change interference; adopting adaptive filtering and L1 norm sparsification to remove multi-source interference; correcting deviation in signal modeling by using a redundant navigation module; and adjusting a signal processing strategy based on a real-time control and scheduling mechanism. According to the method, a signal modeling guide mechanism based on an interference heat prediction map is introduced, and the dynamic change of electromagnetic environment interference is combined with a signal modeling process, so that an interference sensitive area is recognized in advance, and structural sparse constraint is applied; and a blind area lacking sensing of interference at the initial modeling stage in the traditional technology is eliminated.

The invention discloses a multipath effect suppression method for indoor visible light positioning, relates to the technical field of indoor visible light communication and positioning, and aims to solve the problems in the prior art, the method comprises the following steps: constructing a fractional order chaotic signal generator and starting to generate a chaotic sequence signal; the chaotic sequence signals are modulated and loaded to an LED array and a driving circuit thereof, and optical signals carrying fractional order chaotic characteristics are generated and transmitted; after being propagated indoors, the optical signal is acquired by a photoelectric detector, is preprocessed and then is transmitted to a field FPGA (Field Programmable Gate Array); in the FPGA, based on a compressed sensing theory, modeling the received signal and constructing an adaptive sensing matrix to obtain a compressed observation signal; iteratively recovering sparse channel response from the compressed observation signal by adopting a path focusing guide orthogonal matching pursuit algorithm; and the FPGA extracts main path information from the reconstructed sparse channel response, and calculates a final positioning coordinate in combination with an arrival time positioning model. And in indoor visible light positioning, the method has a good capability of resisting a multipath effect.

The invention discloses an induction detection system for production and manufacturing based on artificial intelligence and a regulation and control method, and belongs to the field of artificial intelligence. Comprising an edge data acquisition module, a depth image recognition module, a dynamic sensor integrated array, an artificial intelligence analysis module, an intelligent abnormity feedback module and a linkage execution control module. The edge data acquisition module is deployed at key nodes of a production line, models pressure, current, temperature, vibration and other signals, and performs cross sampling with the sensor array. The depth image recognition module adopts a structured light laser array and a multi-phase shift interference technology to extract a morphology gradient map in real time. And the artificial intelligence analysis module fuses the multi-scale convolutional network and the time sequence reasoning unit, and performs high-dimensional alignment and modeling on the double-source data to form a multi-resolution sensing field. And the intelligent abnormity feedback module generates a response grade score, and realizes millisecond-level control mapping with the linkage control module based on a state path. The method has the beneficial effect that the accuracy and response speed of abnormal recognition in the manufacturing process are improved.

The invention discloses a 360-degree whole-airspace direction-of-arrival estimation method based on a space sectorization neural network, which mainly solves the problems of poor accuracy, high model training complexity and the like in the whole-airspace interval direction-of-arrival estimation in the prior art, and comprises the following implementation steps of: modeling a whole-airspace received signal and constructing neural network input; dividing the airspace into sectors and calculating sector indexes; mapping the direction of arrival of the whole airspace to a reference sector by using a sector index; designing a space sectorization neural network; training and reasoning a space sectorization neural network; and recovering the direction of arrival of the whole airspace by using the obtained sector information and the mapped angle value. According to the method, mapping and estimation of the full-airspace direction of arrival in a reference sector which is a high-performance interval are achieved by introducing space sector information, the method has the advantages of being high in direction of arrival estimation accuracy, high in robustness, easy to train and the like, and the method has wide prospects in practical application such as a new-generation wireless communication system, passive positioning and target detection.

The invention discloses a control method and system of an intelligent massage robot, and relates to the field of intelligent robots. The method comprises the following steps: performing multi-modal dynamic perception fusion, and processing sensor data by using an attention mechanism deep learning model to obtain a body state; modeling and judging a muscle state based on the bio-electricity signal; adjusting a massage reference in combination with environmental parameters; a personalized massage strategy is generated through reinforcement learning; and real-time feedback correction ensures the effect and safety. The system comprises a multi-mode sensing module and the like. The method solves the problems that in the prior art, accuracy is insufficient, and the method is difficult to adapt to individual and environment differences, and has creativity and practicability.

The invention relates to a multi-polarization sparse frequency hopping signal super-resolution one-dimensional distance imaging method and system, and the method achieves the modeling of a multi-polarization channel signal into a multi-observation vector model, effectively utilizes the information of each polarization channel, and avoids the defect of multi-polarization channel fusion matching after the independent processing of a single-polarization channel. Meanwhile, sparse frequency hopping radar signal one-dimensional distance imaging is modeled as a weight atom norm minimization problem, and an alternating direction multiplier method is adopted for rapid solving, so that a dictionary matrix does not need to be established, an off-grid error is avoided, a minimum atom distance constraint is avoided, and the method has a super-Rayleigh resolution capability. It needs to be noted that the method is high in flexibility and suitable for any one or combination of multiple polarization channels in four polarization channels of HH, HV, VH and VV, the super-resolution high-quality one-dimensional range profile of a radar target can be effectively obtained, and the method has high engineering application value.

The invention discloses a multi-hop RIS (Radio Information System) signal coverage method without CSI (Channel State Information) dependency, which belongs to the field of communication, and is characterized in that modeling is carried out on an incident signal of each RIS based on phase compensation, the modeling is more accurate compared with a traditional point source model, a codebook solution method capable of uniformly covering the next RIS is designed in the transmission stages of BS-RIS-RIS and RIS-RIS-RIS, and the coverage efficiency of the next RIS is improved. According to the method, the energy transfer efficiency of the next RIS can be improved, an optimization problem can be established to obtain an RIS codebook for beamforming only by considering a signal transmitting position and a signal receiving position needing to be enhanced during signal modeling, a complex channel estimation process is not needed, computing resources are saved, and on the premise that channel state information is not needed, the energy transfer efficiency of the next RIS can be improved. A phase control matrix of each RIS block in the multi-hop RIS is obtained, and signal enhancement in a traditional communication signal range scene such as a mine hole is achieved by controlling each RIS block.

The invention relates to the technical field of signal processing, in particular to a periodic signal modeling method and device, electronic equipment and a storage medium, and the method comprises the steps: obtaining a coordinate time sequence of a target navigation satellite system; preprocessing the coordinate time sequence to obtain a preprocessed coordinate time sequence, and correcting the preprocessed coordinate time sequence to obtain a corrected coordinate time sequence; estimating the corrected coordinate time sequence to obtain a sine coefficient of periodic amplitude, a cosine coefficient of periodic amplitude and periodic frequency deviation; the method comprises the following steps: establishing a coordinate time sequence model, decomposing, establishing an initial harmonic model, estimating to-be-estimated parameters of the initial harmonic model by using a preset estimation strategy to obtain an estimation result, and establishing a final harmonic model according to the estimation result and the initial harmonic model, thereby solving the problem of systematic deviation caused by empirical period length assumption in coordinate time sequence modeling. And the seasonal deformation inversion precision and the earth crust movement rate estimation reliability are improved.

The invention discloses a virtual synchronous machine key parameter optimization method giving consideration to transient power angle stability and short-circuit current suppression. The method comprises the following steps: establishing a VSG dynamic model; analyzing and calculating VSG short-circuit current and transient power angle stability respectively; analyzing key parameters influencing VSG short-circuit current and transient power angle stability by using small signal modeling to obtain a key parameter configuration range; according to the key parameter configuration range and the requirements for short-circuit current suppression and transient power angle stability, a VSG parameter optimization model is designed, and an improved genetic algorithm IGA is used for solving. And it is ensured that short-circuit current is suppressed during the optimized VSG fault period, and the transient power angle is kept stable. The invention aims to realize the effects of transient stability improvement and short-circuit current suppression only by optimizing parameters without adding extra strategies.

The invention relates to the technical field of miniature photovoltaic inverters, in particular to a three-phase miniature photovoltaic inverter discretization small signal modeling method and system. Establishing a state-space equation according to the working modes of the three-phase micro photovoltaic inverter and determining the switching sequence of each mode; solving the state-space equation based on the working mode and the switching sequence to obtain a discrete iteration equation of the state quantity; separating the state quantity and the duty ratio into a steady-state component and a small-signal component, and converting the nonlinear large-signal discrete iteration equation into a linear small-signal discrete iteration equation; and establishing a z-domain transfer function according to the linear small signal discrete iteration equation, and converting the z-domain transfer function into an s-domain transfer function by using a forward Euler method to obtain a discrete small signal model. According to the method, the switching process among all modes of the three-phase miniature photovoltaic inverter is completely described through a discrete time mapping method, and the modeling precision is improved; and meanwhile, accurate conversion from the time domain to the frequency domain is realized, and a reliable basis is provided for stability analysis of a grid-connected system.

A segmented modeling method based on symmetrical segmentation of a travelling-wave electro-optic modulator, comprising steps: performing modeling simulation on electrical properties of an electro-optic modulation material of a silicon photonic modulator, and extracting electrical parameter data; performing optical simulation on a laser waveguide formed by the preprocessed electro-optic modulation material, and extracting optical waveguide parameter data; performing modeling simulation on an unloaded traveling-wave electrode, and extracting transmission line parameter data; performing small signal modeling analysis and calculation, and performing step-by-step segmentation processing on a medium-loaded traveling-wave electrode in a symmetrical segmentation manner, and performing data analysis and extraction on a simulation result to obtain a parameter result of system design; and the like. The problems of large amount of calculation, low speed and low efficiency can be solved.

The invention discloses a robust adaptive beam forming method based on a depth migration reconstruction network, which mainly solves the problems of signal self-cancellation and insufficient robustness of the existing beam former under non-ideal conditions, and comprises the following implementation steps of: modeling an array receiving signal; constructing real value signal covariance matrix input of the reconstruction network; designing an interference and noise covariance matrix reconstruction network based on a Unet framework; designing a guide vector estimation network based on a dual migration mechanism; real-value label construction and network generalization training are carried out; and calculating a beam forming weight vector. Under typical non-ideal conditions of random signal observation errors, coherent source local scattering errors and the like, the interference and noise covariance matrix and the expected signal guide vector can be accurately reconstructed, the signal self-cancellation phenomenon is effectively avoided, the robustness of a beam former is enhanced, and the method can be used for low-altitude target tracking, medical ultrasonic imaging and other scenes.

The invention discloses a digital self-interference cancellation method and device, electronic equipment and a storage medium, and the method comprises the steps: obtaining a to-be-processed signal, carrying out the modeling of a transmitting signal and a receiving signal containing a self-interference signal, and obtaining a mathematical model; and according to the mathematical model, performing dechirp processing, filtering processing and reconstruction processing in different time periods to obtain a signal completing self-interference cancellation. According to the method, modeling is carried out on a receiving and transmitting signal containing a self-interference signal and a jammer transmitting and receiving signal; establishing mathematical models for transmitting and receiving signals in different time periods; according to a mathematical model of a transmitting signal and a receiving signal containing a self-interference signal, dechirp processing, filtering and reconstruction are carried out in each time period, the implementation process is simple and convenient, digital self-interference cancellation can be efficiently realized, and the method can be widely applied to the technical field of signal processing.

The invention discloses a time-frequency cooperative multi-sub-pulse adaptive matched filtering main lobe intermittent sampling interference resisting method, which comprises the following steps of: modeling a radar multi-sub-pulse transmitting signal to obtain an echo signal, modeling a radar system total receiving signal, filtering an interference signal, recovering a target signal, and obtaining a pulse pressure result. According to the method, multi-channel pulse compression is completed, then distance gate alignment is carried out, finally, distance and speed information of a real target is further highlighted through intra-sub-pulse coherent accumulation and inter-sub-pulse coherent accumulation, and intermittent sampling interference is effectively suppressed. According to the method, a multi-sub-pulse structure is utilized, the interception length of a single sub-pulse by a jammer can be reduced, so that the interference degree of the single sub-pulse is reduced, and the intermittent sampling interference can be effectively suppressed under the condition that interference prior information does not need to be known.

The invention discloses an RIS-assisted millimeter wave satellite communication system channel estimation method based on PARAFAC. The method comprises the following steps: constructing an RIS-assisted millimeter wave satellite communication system cascade channel model; the method comprises the following steps: modeling received signals of an RIS-assisted satellite communication system into a third-order parallel factor (PARAFAC) model through data reconstruction based on a multi-dimensional structure of an RIS-assisted millimeter wave satellite communication system channel; and performing parallel factorization on received signals of the RIS-assisted satellite communication system by using an alternating optimization method to obtain an estimated value of a model factor matrix, and finally reconstructing an RIS-assisted satellite communication channel by using the estimated value of the factor matrix to obtain a channel estimated value. The RIS-assisted millimeter wave satellite communication system channel estimation method can accurately achieve RIS-assisted millimeter wave satellite communication system channel estimation, and the performance of the RIS-assisted millimeter wave satellite communication system channel estimation method is superior to that of a traditional least square method (LS)-based channel estimation method.

The invention discloses a multi-scale full-parameter large-signal modeling system for an ultra-wideband high-power transistor, which relates to the field of multi-scale full-parameter large-signal modeling and comprises a data module, an extraction module, a model module, an adjustment module and a generation module. Parasitic stripping and parameter extraction are carried out to obtain a frequency domain feature matrix, feature tensor construction and double-branch network training are carried out based on the frequency domain feature matrix and physical size parameters and electrical parameters of a transistor, mapping to an ASM model is carried out to obtain a multi-dimensional fine calibration scalable ASM model MASM, and electrothermal coupling and polarization scattering effect dynamic correction are carried out to obtain a polarization scattering effect. According to the method, the all-working-condition electrode drain physical base ASM model M * ASM-T is obtained, polarization scattering modulation analysis is carried out based on the all-working-condition electrode drain physical base ASM model M * ASM-T, the finally optimized all-working-condition electrode scattering drain physical base ASM model M * ASM-T-S is obtained, and the reliability of system modeling is enhanced.

The invention discloses a GNSS deception jamming suppression method based on inertial navigation auxiliary tracking, and the method specifically comprises the steps: carrying out the signal modeling through coherent integration after a radio frequency front end of a GNSS receiver receives a signal, and obtaining a coherent integration value of an in-phase branch and an orthogonal branch; constructing an observation equation and a state equation through coherent integration values of the orthogonal branch and the in-phase branch, and constructing a code loop phase discriminator error and a carrier loop frequency discriminator error by using coherent integration to obtain the observation equation and the state equation; obtaining deception jamming of different traction speeds by using combined detection quantity of constructed SQM and satellite and inertial information; on the basis of an NEYMAN-PEARSON detection theory framework, the optimal detection performance is sought under the constraint condition that the maximum false alarm probability PFAMAX is met, and robust Kalman filtering suitable for deception jamming suppression is designed; and inputting the state equation and the observation equation into robust Kalman filtering to obtain an interference coefficient and an anti-deception adaptive factor for deception interference suppression. According to the method, deception jamming of slow traction is effectively suppressed.

The invention discloses an energy storage adaptive grid-connected method and device considering power grid transient whole process support, and the method comprises the steps: carrying out the small-signal modeling of a network construction type frequency change, and obtaining a first model; performing small-signal modeling on the power flow to obtain a second model; and according to the first model and the second model, adopting a preset adaptive strategy to adjust and control the network-forming converter. Compared with a traditional controller design method based on fixed parameters, the AVSG can achieve expected performance under different power grid conditions, such as no oscillation, specified steady-state time and minimum overshoot.

The invention provides a multi-input and multi-output frequency coupling admittance modeling method for a follow-up network fan, and belongs to the technical field of large-scale follow-up network type and follow-up network type fan frequency coupling admittance modeling. The technical problem that a network following type GFL and network constructing type GFM doubly-fed fan series-parallel system in a wind power plant lacks an accurate small-signal modeling and analysis method is solved. According to the technical scheme, the method comprises the following steps: S1, establishing an open-loop doubly-fed motor self admittance considering stator and rotor flux linkage dynamics; s2, obtaining frequency domain multiple-input multiple-output admittances of the following network type doubly-fed fan and the constructed network type doubly-fed fan; s3, obtaining a unified multiple-input multiple-output admittance frequency domain model containing a closed loop interconnection system formed by the following network type doubly-fed fan admittance YGFL and the construction network type doubly-fed fan admittance YGFM; and S4, quantitatively evaluating a phase-locked loop parameter and a virtual synchronous control parameter. According to the invention, accurate determination of frequency coupling oscillation is realized.

The invention discloses an enhanced power decoupling control method for a virtual synchronous generator, relates to the technical field of virtual synchronous generators, and solves the problems that a systematic analysis method for a resistance-inductance line power coupling mechanism is lacked and a collaborative design framework of a dynamic power decoupling condition and a steady-state power transmission requirement cannot be established in the prior art. According to the method, firstly, a dynamic coupling coefficient is accurately quantified through small signal modeling, then a voltage amplitude compensation mechanism based on virtual impedance is established, steady-state power transmission constraints are embedded into dynamic decoupling conditions, and virtual impedance parameters have the dual functions of eliminating dynamic coupling and guaranteeing steady-state tracking. The method does not depend on ideal working condition assumption, can calculate the optimal virtual resistance and virtual reactance on line according to real-time line parameters and operation working conditions, improves the adaptability of the VSG to a weak power grid resistance-inductance line, effectively inhibits dynamic cross coupling between power, and enhances the frequency support and voltage support capability of the VSG under a complex power grid condition.

The invention discloses a 4D tensor-based RIS-assisted millimeter wave MIMO-NOMA Internet of Vehicles system channel estimation method, and aims to reduce the influence of serious Doppler frequency shift and sight line path blockage on communication performance, first, a 5G subframe division scheme without changing a standard 5G frame structure is proposed by introducing concepts of aggregation time slot and half time slot, and a 5G subframe division scheme without changing a standard 5G frame structure is provided; modeling of the received signal is facilitated; then, modeling the received signal into a four-order tensor so as to separate channel parameters into four factor matrixes, thereby avoiding parameter coupling; then, the tensor is decomposed in a closed-form solution form; then, carrying out one-dimensional search on a factor matrix obtained by decomposition to extract channel parameters; after channel parameters are obtained, a least square problem is constructed to obtain channel path gains, and solving of a scaling matrix is avoided; finally, experiments verify that the method can accurately estimate the parameters of the channel, and excellent demodulation performance can be realized based on the parameters of the channel.

The invention discloses a rolling bearing vibration response modeling and fault diagnosis method, equipment and a medium. The method comprises the following steps: establishing an unequal-interval and amplitude-modulated exciting force sequence signal model; and modeling a vibration impact response signal, simulating an envelope demodulation numerical value, and diagnosing faults. According to the invention, the rolling bearing is taken as a research object, a vibration impact response signal model is established, the model is finer, and the vibration mechanism of the bearing can be simulated more accurately; the characteristics of impact excitation, response signals and envelope signals can be analyzed in detail in sequence, unequal interval and amplitude modulation characteristics of excitation force are decoupled from the vibration principle, fault characteristics of impact response and envelope are revealed, and rolling bearing fault diagnosis considering unequal interval and amplitude modulation excitation force can be realized.