82 results about "Bandwidth limitation" patented technology

The invention discloses a power cable tiny defect positioning method based on a CFI-Z algorithm, and the method comprises the steps: obtaining a reflection coefficient vector of a head end of a power cable obtained through sweep frequency signals based on multiple frequencies, and obtaining a minimum norm least square solution and a closed solution of a power cable fault positioning factor according to a continuous frequency-increasing Z transformation matrix; and obtaining the sparse intensity of the minimum norm least square solution and the closed solution to obtain the final solution of the power cable fault positioning factor, and finally obtaining the position of the power cable defect according to the head end reflection time domain sequence of the power cable to complete the positioning of the early defect of the cable. According to the invention, the problems of insufficient high-frequency components and bandwidth limitation in the injected pulse are solved, so that the defect positioning sensitivity of the power cable is high, the anti-noise capability is strong, the positioning error is small especially under the condition of a long cable or a cable with small defects, and the method has a good effect in early-stage small defect positioning.

The invention discloses a call recording method based on dynamic sampling rate adjustment and a Bluetooth earphone, and aims to improve the quality and stability of call recording in a wireless transmission environment. According to the method, uplink audio data and downlink audio data are collected at the same time through the Bluetooth headset, and the transmission rate of a downlink data packet is monitored in real time. When the rate is lower than the preset threshold value, the audio sampling rate is automatically reduced from 16 kHz to 8 kHz to adapt to bandwidth limitation, and recording interruption or tone quality reduction is avoided. The adjusted audio data is cached through a double-layer cache mechanism after being coded and compressed, the first cache temporarily stores the adjusted audio data, and the second cache manages data packets to be sent and retransmitted, so that the continuity and integrity of data transmission are ensured. The method is suitable for wireless audio equipment such as a Bluetooth earphone, and the reliability, adaptability and user experience of call recording are effectively improved.

The invention discloses an ultra-wideband circulator based on a periodic modulation topology circuit, and belongs to the technical field of microwave and radio frequency nonreciprocal circuits. The working bandwidth range of the circulator is widened, and non-reciprocal transmission is achieved through non-magnetic materials. A time sequence control unit is respectively connected with a Floquet topology circuit layer, a clock signal driving module, a reset signal driving module and a start signal driving module; the Floquet topology circuit layer is respectively connected with a first coupling port, a second coupling port and a third coupling port; the other ends of the first coupling port, the second coupling port, the third coupling port, the clock signal driving module, the reset signal driving module and the starting signal driving module are respectively grounded; the Floquet topology circuit layer adopts a six-layer parallel network structure, and each layer of network structure comprises a coupling capacitor and three N-type MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) switches. The advantages of the switched capacitor structure are utilized, and the signal processing capacity which is high in integration level, small in size and capable of breaking through delay-bandwidth limitation is achieved.

The invention discloses a modulation identification method based on microwave photon frequency-time mapping. The method comprises the following steps: firstly, performing microwave photon frequency-time mapping on a to-be-measured microwave signal, and mapping frequency information of the to-be-measured microwave signal to a time domain to obtain a time-frequency characteristic of the to-be-measured microwave signal; and inputting the time-frequency characteristics of the to-be-detected microwave signal into a pre-trained neural network model so as to identify the modulation form of the to-be-detected microwave signal. The invention also discloses a modulation identification device based on microwave photon frequency-time mapping. Compared with the prior art, on the basis of a microwave photon frequency-time mapping model, Fourier transform is directly completed through an optical device, a radio frequency signal is modulated to be processed in an optical domain, time delay characteristics of dispersion broadening and compression are combined, the picosecond-level time stretching precision is achieved, the instantaneous bandwidth limitation of a traditional spectrum analyzer is broken through, and the spectrum analysis precision is improved. Frequency spectrum processing of large-bandwidth signals can be completed in real time, computing resources are saved, and the real-time performance of modulation identification is improved.

In various examples, methods and systems are provided for sampling and transmitting the most useful information from a radar signal representing a scene while staying within the computational and storage confines of a standard automotive radar sensor and the bandwidth constraints of a standard communication link between a radar sensor and processing unit. Disclosed approaches may select a patch of frequency bins that correspond to radar signals based at least on proximities of the frequency bins to one or more frequency bins corresponding to at least one peak and / or detection point in the radar signals. Data representing samples corresponding to the patch of frequency bins may be transmitted to the processing unit and applied to one or more machine learning models in order to accurately classify, identify, and / or track objects.

The invention provides an online detection system and method for electrochemical alternating-current impedance of a fuel cell, and aims to solve the problems of limited measurement frequency range and insufficient control precision caused by bandwidth limitation of a controller in the existing EIS online detection technology, and the online detection system comprises a fuel cell and a power supply system of a DC-DC converter, the disturbance signal generation module generates a sine disturbance current signal; the feedforward and feedback control module takes the total current reference signal as a control target, and calculates to obtain a final adjustment duty ratio for driving the DC-DC converter; when the DC-DC converter is driven by the final adjustment duty ratio, a data acquisition module synchronously acquires an input voltage and an input current which are input into the DC-DC converter as a response voltage signal and a response current signal; and the impedance demodulation module is used for demodulating and calculating the electrochemical alternating current impedance of the fuel cell based on the frequency of the response voltage signal, the response current signal and the sine disturbance current signal.

The invention provides a BOTDR system Brillouin gain spectrum correction method and system based on a symmetric kernel, and belongs to the technical field of optical fiber sensing. The method comprises the following steps: acquiring Brillouin gain spectrum information along a sensing optical fiber; acquiring amplitude-frequency responses of the balanced photoelectric detector and the band-pass filter in a full frequency band by using a vector network analyzer; performing convolution processing on the obtained Brillouin gain spectrum information along the sensing optical fiber and the amplitude-frequency response of the balanced photoelectric detector and the band-pass filter in the full frequency band to obtain a corrected Brillouin gain spectrum; lorentz fitting is carried out on the corrected Brillouin gain spectrum to extract Brillouin frequency shift, and the Brillouin frequency shift is converted into temperature and strain information. The spectral line symmetry and the signal-to-noise ratio are improved, the symmetry of the corrected Brillouin gain spectrum is remarkably enhanced, the phenomena of peak offset and asymmetric broadening caused by system bandwidth limitation are eliminated, and the extraction precision of the Brillouin gain spectrum is remarkably improved.

The invention discloses an intelligent shock absorption and noise reduction control method for rail transit, and belongs to the technical field of rail transit noise and vibration control. The method aims at solving the problems that traditional passive control measures are poor in adaptive capacity and limited in frequency band, and effective prospective offset is difficult to achieve due to system delay and inaccurate reference signals in existing active control. The method comprises the following steps: synchronously acquiring vibration and noise signals through a sensor array; calculating the contribution weight of vibration to noise by using a cross-domain modal correlation module based on an attention mechanism, and fusing the features; predicting an evolution sequence of vibration and noise in a specific time period in the future by adopting a long-short-term memory network model; synthesizing a target reference signal according to the prediction sequence, and generating an anti-phase control signal through an adaptive filtering algorithm; finally, it is ensured that the total delay of the system is smaller than the feedforward advance time, and an actuator is driven to achieve accurate foresight counteracting. The method is mainly used for improving the self-adaptive capacity and the control effect of the rail transit damping and noise reduction system.

In various examples, methods and systems are provided for sampling and transmitting the most useful information from a radar signal representing a scene while staying within the computational and storage confines of a standard automotive radar sensor and the bandwidth constraints of a standard communication link between a radar sensor and processing unit. Disclosed approaches may select a patch of frequency bins that correspond to radar signals based at least on proximities of the frequency bins to one or more frequency bins corresponding to at least one peak and / or detection point in the radar signals. Data representing samples corresponding to the patch of frequency bins may be transmitted to the processing unit and applied to one or more machine learning models in order to accurately classify, identify, and / or track objects.

The invention provides a distance dimension frequency band extension super wave beam forming method and system. The method comprises the following steps: intercepting a received signal through a sliding window; converting the intercepted signal and the original received signal to a frequency domain; removing the inherent phase of the signal frequency point to obtain processed echo frequency domain data Xp (f); intercepting a signal frequency band Up (f) for the Xp (f) in a window range; performing forward and backward linear prediction on the Up (f), and expanding a signal frequency band; carrying out low-frequency and high-frequency half sub-band division on the expanded signal frequency band; performing fast Fourier inverse transformation on the half sub-bands respectively, and obtaining a distance dimension sum beam RD (r) and a distance dimension difference beam RS (r) to obtain distance dimension super-beam output of the window signal; and overlapping and reserving the windowing signals, and circularly executing the steps on subsequent signal windows. The method has the advantages that the problem that the distance resolution capability is limited by the bandwidth and the problem that the distance resolution capability and the sidelobe suppression capability are contradictory are solved.

The present application relates to the technical field of noise processing, and discloses a noise whitening method, device, equipment and storage medium, the method comprises the following steps: constructing an error function based on an equalization signal and a training sequence; calculating based on the error function to obtain gradient information; updating the tap coefficient of the noise whitening filter based on the gradient information to obtain a target tap coefficient; whitening the colored noise based on the target tap coefficient. The present application updates the tap coefficient of the noise whitening filter by formulating the error function and calculating the gradient, solves the problem that when the channel equalization technology is used to overcome the bandwidth limitation, the equalization enhances the colored noise, leads to uneven noise power spectrum, and thus reduces the IM-DD transmission rate, realizes the whitening of the colored noise, makes the power spectrum flat, and thus significantly improves the performance of the IM-DD system and increases the communication capacity.

A video encoding apparatus including a reconstruction buffer with fixed size and / or bandwidth limitations, and an associated video encoding method. Specifically, a video encoding apparatus includes a data buffer and video encoding circuitry. Encoding of a first frame includes: deriving reference pixels of a reference frame from the reconstructed pixels of the first frame, and storing the reference pixel data in the data buffer for inter-frame prediction, wherein the reference pixel data includes information about the pixel values ​​of the reference pixels. Encoding of a second frame includes: performing prediction on coding units in the second frame to determine a target prediction factor for the coding unit. The prediction step performed on the coding unit includes: determining the target prediction factor of the coding unit based on whether a search range for the prediction factor of the coding unit for the reference frame includes at least one reference pixel of the reference frame that cannot be accessed by the video encoding circuitry.

The invention relates to the technical field of control or regulation systems, in particular to an implementation method of a multi-agent speedless measurement control device based on STM32. The method comprises the following steps: establishing a communication topological graph of a multi-agent system; determining a dynamical model of the agent node and an inclusion control protocol without speed measurement; a distributed hardware system platform based on an STM32 microcontroller is constructed; based on the platform, a collaborative development environment with STM32CubeMX and Keil uVision5 as the core is constructed. According to the invention, the STM32 microcontroller is taken as a core, the control instruction of the intelligent agent is directly calculated and is driven to execute, and only the positions of the intelligent agent and the neighbor node are taken as control input, so that a control target can be efficiently and stably achieved; the challenges of computing power, storage and bandwidth limitation when distributed inclusion control is deployed on a hardware platform based on an STM32 microcontroller are solved.

The invention relates to a method and a system for video transmission based on millimeter wave, 5G and Wi-Fi hybrid networking, a uniform resource pool of millimeter wave, 5G and Wi-Fi is constructed through a network interface abstraction layer, paths are dynamically allocated for transmission units by combining video stream segmentation and utilizing a multipath transmission protocol, and aggregation and parallel transmission of heterogeneous network bandwidth resources are realized. Compared with a single network or a simple main and standby scheme, the method breaks through the physical bandwidth limitation of a single frequency band, effectively solves the problems of spectrum congestion and signal shielding in a large-space multi-user scene, and greatly improves the total throughput and transmission stability of the system, thereby supporting the concurrent transmission of XR video streams with higher resolution.

This invention discloses a circularly polarized selective wireless energy harvesting rectifier, comprising a metasurface module, a power combining module, and a rectification module. The metasurface module includes multiple absorbing units arranged in a periodic array. Each absorbing unit includes a resonant structure on the front side of a dielectric substrate and a metallized via penetrating the substrate. The resonant structure is a conductive ring with two offset openings, one of which contains a capacitive element. The power combining module includes a power combining network disposed on the back side of the dielectric layer of the power combining network. The input terminal of the rectification module is connected to the output terminal of the power combining module. This rectifier simultaneously solves the two core problems of polarization mismatch and bandwidth limitation. It integrates polarization selection, wideband energy harvesting, and high-efficiency rectification functions. Its core function is to efficiently selectively absorb and convert right-hand circularly polarized waves while generating strong reflection of left-hand circularly polarized waves to suppress interference.

Bandwidth adaptation in a transmission circuit is provided. The transmission circuit includes a power amplifier circuit that amplifies a radio frequency (RF) signal based on a modulated voltage, an envelope tracking integrated circuit (ETIC) that generates the modulated voltage based on a modulated target voltage, and a transceiver circuit that generates the RF signal and the modulated target voltage. The RF signal may have a wide modulation bandwidth but the ETIC may have a lower bandwidth limit, which can cause distortion in the modulated voltage and the RF signal. In this regard, the transceiver circuit is configured to generate the modulated target voltage in a lower bandwidth than the bandwidth limit when the modulation bandwidth of the RF signal exceeds the bandwidth limit of the ETIC. As such, the transmission circuit can process the RF signal across the wide modulation bandwidth without causing distortion in the RF signal.

This reception device comprises: a reception unit that receives, as a reception signal, a transmission signal transmitted from a transmission device; a matching filter unit that limits the bandwidth of the reception signal to the bandwidth of the transmission signal; and a Doppler shift estimation / correction unit that estimates and corrects the Doppler shift of the reception signal. The matching filter unit is disposed downstream of the Doppler shift estimation / correction unit.

This communication device comprises: a control circuit for disposing a signal for sidelink communication in a frequency resource that satisfies a bandwidth limit regarding the frequency range in an unlicensed band; and a transmission circuit for transmitting the signal.

The present invention is applicable to the technical field of millimeter-wave radio frequency front-end architecture research, and provides a radio frequency front-end system based on an impedance transformation switch network, including: a main power amplifier, a secondary power amplifier, a low-noise amplifier, a quarter-wavelength transmission line, an impedance transformation switch network, an antenna, a main power amplifier input interface, a secondary power amplifier input interface, and a low-noise amplifier output interface. Based on the radio frequency front-end system provided by the present invention, using an impedance transformation network instead of a switch in the transmit link can achieve the effects of no additional switch insertion loss and no bandwidth limitation for the transmit link signal, and setting a single-pole single-throw switch in the receive link can improve the isolation between the transmit link and the receive link. This way of changing the radio frequency front-end system architecture can maximize the conversion of the power amplifier efficiency into the transmit link efficiency, thereby reducing the system power consumption.

The present application relates to the field of ultra-precision manufacturing technology equipment, and particularly relates to a series-parallel hybrid three-axis FTS device driven by electromagnetism and piezoelectricity and a control method thereof.The device comprises a plane-axis motion assembly driven by electromagnetic stress and a vertical-axis motion assembly driven by piezoelectricity; the plane axis is directly driven by electromagnetic stress to drive a transmission shaft, and the inertia of the motion component is low; the piezoelectric driver is nested in the interior of the transmission shaft of the plane axis, and the vertical axis is fixed to the front and rear end surfaces of the transmission shaft to realize a series-parallel hybrid structure and eliminate the inertia coupling between the shafts.The X-axis adopts a two-degree-of-freedom control method in which a feedback path is connected in parallel with a feedforward path to realize fast and non-overlapping tracking of a step wave signal.The present application breaks through the bandwidth limitation of the traditional structure, realizes the compatibility of motion decoupling and large-stroke high-frequency motion, guarantees the high positioning precision of the tool end and the high rigidity of the structure, and meets the efficient and high-precision processing requirements of metal microstructure components.

The invention relates to a method and a device for optimizing a large language model interactive service for a weak network environment, which are particularly suitable for regions with limited network infrastructures. The method comprises the following steps: establishing an interactive self-adaptive hierarchical service architecture of a large language model, and dynamically adjusting LLM context management and generation control according to a network condition; establishing a semantic local cache mechanism oriented to large language model interaction, and performing local storage and offline response of LLM specific key data at a user equipment side; establishing an asynchronous fault-tolerant processing mechanism of large language model interaction, and providing an interaction continuity guarantee when the network is abnormal; and establishing a transmission optimization strategy of the large language model, and optimizing the transmission characteristics of the data. According to the method, the special problems of response delay, interaction interruption, bandwidth limitation and the like of interactive application of the large language model in a weak network environment are solved, and the service stability and the user interaction fluency of the large language model are effectively improved.

The invention discloses a PolSAR two-dimensional dynamic bandwidth variational mode decomposition method based on Bayesian parameter selection, a computing device and a computer readable storage medium, and the method comprises the following steps: carrying out the preprocessing of a scattering matrix of polarized SAR data, and extracting the intensity information of six polarized channels; updating each modal component through an alternating direction multiplier method, and performing two-dimensional inverse Fourier transform on each modal component; constructing a Bayesian optimization objective function, and updating an optimal evaluation value based on a Gaussian process and an expectation improvement function; outputting the optimal modal number when the maximum evaluation frequency is reached; and taking the optimal mode number as a parameter, and obtaining a final decomposition result through two-dimensional dynamic bandwidth variational mode decomposition. The method has the advantages that the two-dimensional variational mode decomposition algorithm is rewritten, so that the method has the adaptive characteristic of bandwidth limitation; secondly, a Bayesian optimization design objective function is introduced on the basis of two-dimensional dynamic bandwidth variational mode decomposition, so that a key parameter K can be adaptively selected;

The invention discloses an equalization method for compensating frequency offset and channel linear damage without data assistance, and the method comprises the following steps: receiving an optical transmission signal and a local oscillator signal through a coherent receiver module, and carrying out the frequency mixing of the optical transmission signal and the local oscillator signal, so as to form a frequency mixing signal; converting the frequency mixing signal into an analog signal, sampling the analog signal, and converting the analog signal into a digital signal; and a digital signal processing module is used for processing the digital signal, and compensating signal frequency offset damage and linear damage such as dispersion and device bandwidth limitation. According to the equalization method for compensating frequency offset and channel linear damage without data assistance, any training sequence is not needed, spectrum resources are saved, the advantages of multiple rates and multiple modulation formats are met, and linear damage such as signal frequency offset damage, dispersion and device bandwidth limitation can be compensated at the same time.

An electronic device, method and computer program product provide clear video feeds while operating within a data bandwidth limitation. The electronic system monitors eye gaze direction of a local participant viewing a display and positioned in a field of view of the at least one image capturing device. The electronic device receives, via a communications subsystem, and presents, at the display, more than one video feeds of respective participants in a video communication session. In response to determining that at least one video feed is not being gazed at by the local participant, the electronic system captures a video snippet of each of the at least one video feed and presents the video snippet within a participant tile in place of the respective video feed. The electronic system presents a live video feed in a corresponding participant tile that is being viewed by the local participant.

The application discloses a self-adaptive voice-text hybrid communication method and system based on an ad hoc network, and belongs to the technical field of communication transmission. In the method, a voice signal is collected at a sending end, link quality is evaluated according to a channel state, a corresponding coding mode is determined according to the link quality, compression coding is carried out, and the compression-coded data packet is transmitted to a receiving end; at the receiving end, the compression-coded data packet is received, the data packet is decoded, and the decoded data is played. The application is used for solving the technical problems of bandwidth limitation, insufficient anti-interference, response lag and system heterogeneity in a complex environment, and provides reliable communication support for intelligent data transmission.

A self-tuning, resonant cavity transmitter combiner joins multiple RF transmitters and combines their signals onto a single transmission line. An additional tuning element is added to the junction of the signal paths to overcome the bandwidth limitations of the transmission lines joining the signal paths. An algorithm was developed to optimize the RF performance of the combiner by sampling the RF signals at various points in the RF circuit.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit an indication of a capability of the UE to support a restricted bandwidth for data signaling. The UE may receive an indication of a bandwidth part for control signaling and an indication of a set of frequency domain resources for the data signaling. The set of frequency domain resources may correspond to a subset of the bandwidth part in accordance with the restricted bandwidth. The UE may communicate the control signaling over the bandwidth part and data signaling over the set of frequency domain resources. In some cases, the bandwidth restriction may correspond to a bandwidth size for the set of frequency domain resources or a number of resource blocks in the set of frequency domain resources.

The present application relates to the technical field of terahertz spectrum detection, in particular to a kind of directly encoded waveform's atomic terahertz spectrum detection method and device, the detection method uses " direct modulation coding + algorithm reconstruction", the bandwidth of the terahertz frequency domain spectrum obtained overcomes the narrow bandwidth defect of atomic detection, the frequency coverage range of its spectrum is determined by the bandwidth of terahertz modulator, is not limited by the intrinsic narrow bandwidth of atomic detector, realizes the terahertz spectrum fast and efficient detection of more than GHZ bandwidth, can be applied to gas component detection, substance concentration analysis, nondestructive testing and other fields, has good application value.

The invention provides a dynamic compensation method for a temperature-pressure composite sensor, which comprises the following steps of: acquiring amplitude-frequency and phase-frequency characteristic curves through frequency response test, determining bandwidth limitation and phase lag characteristics, and designing a digital compensation filter by adopting an inverse system method to improve amplitude flatness and phase linearity in a preset frequency band; meanwhile, linear subintervals are divided according to piecewise nonlinear characteristics, a dynamic compensation model is established, and gain and phase correction coefficients are extracted; and according to a measured value, switching subinterval models in real time and adjusting a filtering coefficient to ensure a dynamic tracking characteristic. According to the invention, the optimized frequency response characteristic is finally integrated to an output signal processing flow, and the measurement precision and response speed of the temperature and pressure sensor under complex working conditions are significantly improved.

The embodiment of the invention provides a signal processing device, a signal processing method, electronic equipment and a storage medium. The device comprises a signal processing circuit and a digital filter associated with attenuation compensation of an input signal, and the signal processing circuit is used for determining a bandwidth limit range of the digital filter based on a signal parameter associated with the input signal and a device parameter of the signal processing device; the signal processing circuit is also used for configuring a bandwidth limit value of the digital filter, and the bandwidth limit value is determined based on the bandwidth limit range; and the digital filter is used for carrying out attenuation compensation on the input signal based on the bandwidth limit value to obtain an output signal.