756 results about "Signal frequency" patented technology

The invention belongs to the technical field of unmanned aerial vehicle full-aviation electromagnetic detection, and particularly relates to a full-aviation frequency domain electromagnetic emission system and a control method. A broadband frequency mixing and matching circuit is connected in series between an H-bridge power inverter and an emission coil of an unmanned aerial vehicle electromagnetic emission system; the broadband mixing and matching circuit comprises a first resonance unit formed by connecting a fixed capacitor and an adjustable inductor in parallel and a second resonance unit formed by connecting a fixed capacitor and an adjustable inductor in parallel, and the first resonance unit and the second resonance unit are connected in series. The adjustable inductor is matched with the dynamic impedance of the inductive load by adjusting the inductance value, and the broadband frequency mixing and matching circuit can adjust the impedance in real time, so that the matching of different resonant frequencies is realized, and the frequency range of a matching signal can be obviously widened.

A data and clock recovery circuit, a receiving apparatus, a circuit system, a vehicle-mounted device, a vehicle, and a data and clock recovery method are provided. The data and clock recovery circuit includes a sampler, a phase detector, a multi-order filter, a frequency change detection circuit, and a selector. The sampler is configured to sample an input signal based on a multi-order filtered signal to generate a sampled signal. The phase detector is configured to determine a phase difference in the sampled signal based on the sampled signal. The multi-order filter is configured to generate the multi-order filtered signal based on the phase difference. The frequency change detection circuit is configured to determine a frequency change direction of a spread spectrum clock in the input signal by using the phase difference.

The invention provides a speech recognition accuracy evaluation statistical method, which comprises the following steps: acquiring current underwater depth, helium-oxygen mixed gas density, original speech waveform and respiratory resistance, analyzing to obtain waveform change amplitude and gas density change amplitude, and recognizing main frequency components in the original speech waveform; combining the corrected voice waveform with the helium-oxygen mixed gas density and the respiratory resistance to evaluate the stability degree of the sound production gas flow, and determining audio sample classification according to the stability degree of the sound production gas flow; and classifying and grouping the audio samples according to a preset depth interval so as to adapt to acoustic environment changes of different depths, and identifying a voice signal frequency characteristic offset rule of different underwater depth groups so as to obtain voice identification standards for different underwater depth levels.

The invention relates to the field of unmanned aerial vehicle communication, in particular to an unmanned aerial vehicle communication frequency band monitoring method and interference method.The method comprises the following steps that 1, background noise signals of a full frequency band are collected, Fourier transform is conducted on the collected background noise signals, and a signal frequency band with energy exceeding a preset threshold value is extracted; step 2, acquiring each signal frequency band with energy, and performing adaptive IMF component decomposition on each signal frequency band with energy; 3, screening the IMF components according to the impact energy of the IMF components, and performing signal reconstruction on the screened IMF components; and step 4, inputting the reconstructed signal into the neural network model for rule analysis, and generating a risk coefficient of existence of communication in a signal frequency band according to the rule analysis.

The embodiment of the invention provides a dual-frequency base station antenna, and belongs to the technical field of antenna equipment, the dual-frequency base station antenna comprises a grounding plate, two dielectric substrates are laminated on the grounding plate, each dielectric substrate is correspondingly provided with a radiation unit, and the radiation signal frequency bands of the two radiation units are different; the radiation unit comprises a radiation patch and a metal through hole array which are arranged on the dielectric substrate, the radiation patch is a fan-shaped patch, the metal through hole array is arranged around the arc-shaped edge of the radiation patch, and the metal through hole array, the grounding plate, the dielectric substrate and the radiation patch jointly form a substrate integrated waveguide resonant cavity; the substrate integrated waveguide resonant cavity is configured to couple and excite the radiation patch after being externally excited so as to radiate a signal of a preset frequency band through the radiation patch. The dual-frequency base station antenna provided by the embodiment of the invention has excellent pilot frequency isolation performance, and can realize bandwidth expansion and radiation optimization effects.

The invention discloses a laser scanning system, and belongs to the technical field of laser signal processing. The system comprises a laser emission and control module, a scanning device, a receiving device, a signal processing module and a self-adaptive learning module. And the signal processing module extracts the instantaneous frequency of the beat signal through Fourier transform and Hilbert transform, and dynamically adjusts the input voltage based on an iterative algorithm optimized by the adaptive learning module to realize linearization correction of the beat signal frequency and a nonlinear mapping linearization interpolation scheme. The adaptive learning module stores historical correction data, dynamically optimizes parameters such as step length and convergence conditions of an iterative algorithm by using a machine learning method, and improves the adaptability and correction precision of the system in a complex environment. According to the method, full-closed-loop intelligent control from signal acquisition and processing to parameter optimization is realized, and the method has the characteristics of high precision, strong robustness and low manual intervention, and is suitable for the fields of laser radar, three-dimensional scanning, precise distance measurement and the like.

The invention belongs to the technical field of radio frequency identification, and particularly relates to an unmanned aerial vehicle radio frequency fingerprint identification method for different signal-to-noise ratios based on a time-frequency graph. The invention provides a radio frequency fingerprint identification method for different signal-to-noise ratios based on a time-frequency graph and a YOLOV8 image identification technology on the basis of a traditional unmanned aerial vehicle radio frequency signal fingerprint identification technology, and the method mainly comprises the steps: constructing a new training data structure, specifically, converting an IQ signal into the time-frequency graph, and carrying out the recognition of the time-frequency graph and the YOLOV8 image identification technology. And then performing arrangement according to the unmanned aerial vehicle type (J), the signal bandwidth (B), the signal frequency band (F) and the signal-to-noise ratio (R) to obtain a structured data set, and performing identification by using an improved YOLOV8 model. Compared with the prior art, the method further improves the accuracy and speed of unmanned aerial vehicle identification, and is a scheme for identifying the model of the unmanned aerial vehicle on the hardware level without information matching. According to the method, high sensitivity of the model to a low-signal-to-noise-ratio signal is kept, and meanwhile, a large amount of misrecognition caused by low confidence is effectively inhibited.

The invention discloses a data processing method based on an ultrahigh frequency original signal and a storage medium, and relates to the field of data processing, and the method comprises the steps: carrying out the adaptive gain adjustment collection of the ultrahigh frequency original signal, and enabling the signal amplitude to be stabilized in a preset effective interval through the dynamic adjustment of a gain parameter, acquiring initial acquisition data containing complete discharge characteristics; performing time-frequency domain combined noise reduction preprocessing on the initially acquired data, constructing an adaptive threshold function based on signal frequency domain distribution characteristics, and filtering background noise and non-discharge interference signal components; according to the method, the signal amplitude is dynamically stabilized through adaptive gain adjustment, it is ensured that initial collection data completely contains discharge characteristics, the problem of information loss caused by signal fluctuation is solved, the adaptive threshold is constructed based on frequency domain energy characteristics through time-frequency domain combined noise reduction, background noise and interference components are accurately filtered out, and the signal purity is improved.

To provide a communication system capable of maintaining a FDD system communication between a base station apparatus and a terminal apparatus and reducing the weight and power consumption of a radio relay apparatus.SOLUTION: A service link and a feeder link use the same frequency band (shared frequency band) in which an FDD uplink band in which a plurality of frequency channels are adjacently arranged and an FDD downlink band in which a plurality of frequency channels are adjacently arranged are spaced apart from each other via a predetermined guard band. A radio relay apparatus includes a shared antenna, a frequency conversion unit that converts a frequency of an REV (reverse) link signal in a first frequency channel of an FDD uplink band into a frequency of a second frequency channel of an FDD downlink band, and converts a frequency of an FWD (foward) link signal in the second frequency channel of the FDD uplink band into a frequency of a first frequency channel of the FDD downlink band, and a single power amplifier that amplifies the REV link signal and the FWD link signal.SELECTED DRAWING: Figure 12

A method for detecting interference between a transducer of acoustic signals and a sensor having a mechanical resonance frequency with a frequency band that includes transmitting an acoustic signal within a known range of frequencies, in a sequence during a predetermined time window, monitoring the output signal from the sensor within said time window, comparing the transmitted signal with the sensor output signal and detecting deviations in the sensor output signal corresponding to frequencies in the acoustic signal, and determining the acoustic frequencies interfering with the sensor signal. A system for detecting interference including a transducer, configured to emit a sequence of acoustic signals, and a sensor configured to produce an output signal, an analysis unit adapted to monitor said output signal with the acoustic signal.

To provide a liquid dispensing device that can increase the frequency of the drive signal. [Solution] A capacitive load drive circuit that outputs a drive signal to displace a capacitive load comprises: an amplification circuit that outputs an amplified modulated signal by driving a first transistor that is driven in accordance with a first gate drive signal corresponding to a modulated signal obtained by modulating a base drive signal output by a modulation circuit, and a second transistor that is driven in accordance with a second gate drive signal corresponding to the modulated signal; and a demodulation circuit that outputs a drive signal obtained by demodulating the amplified modulated signal, wherein at least one of the first transistor and the second transistor comprises a first layer containing a first nitride semiconductor and a second layer containing a second nitride semiconductor having a larger band gap than the first nitride semiconductor, with the second layer positioned above the first layer, in a liquid dispensing device.

The embodiment of the invention discloses a maritime search and rescue target detection method, device and equipment based on a harmonic radar. A specific implementation mode of the method comprises the following steps: generating a plurality of paths of emission excitation signals through a signal processing board and a first wave band receiving and transmitting module; performing electron beam scanning on the target sea surface area according to the antenna module, the first wave band receiving and transmitting module and the multiple paths of transmitting excitation signals; performing waveband front-end processing on the second waveband echo signal to generate four paths of polarized monopulse channel signals; performing frequency domain polarization feature extraction on the four paths of polarization monopulse channel signals to generate a signal frequency domain polarization feature set; and performing adaptive target detection on the signal frequency domain polarization feature set to generate a search and rescue target detection result. According to the embodiment, an S / C harmonic radar and a dual-polarization phased array structure are adopted, and the search and rescue target generates a receivable harmonic echo, so that sea clutter energy is suppressed in two physical dimensions of frequency band and polarization, and stable detection of the search and rescue target is further realized.

The invention discloses a digital signal processing method and system based on an FPGA, relates to the field of digital signal processing, and introduces a staged variable bandwidth CDR strategy. In the initial stage, the signal frequency offset is quickly estimated through feedforward frequency analysis, and a high-bandwidth loop is started on the basis of the signal frequency offset, so that top-speed locking is realized, and the requirements of production testing and other scenes on efficiency are met. When the system confirms that locking is stable through hardware logic, a multi-step interpolation state machine is triggered, the state machine can smoothly switch the coefficient of the loop filter from a high bandwidth mode to a low bandwidth mode without disturbance, and the lock losing risk in the switching process is avoided. Finally, in a stable low-bandwidth mode, the system can perform accurate jitter decomposition and data analysis by using a high-precision recovery clock. In this way, the two modes of rapid capture and high-precision measurement are fused in one operation process, and the static design limitation in the prior art is solved.

The present invention relates to the technical field of chips, and provides a frequency calibration method, an electronic device, a storage medium and a computer program product, the method comprising: determining a current frequency deviation direction of a tested clock, the current frequency deviation direction being a deviation direction of a current frequency of the tested clock relative to a target frequency; adjusting the calibration step length and the calibration code according to the difference between the current frequency deviation direction and the previous frequency deviation direction; and if the adjusted calibration step length reaches the preset step length, calibrating the output signal frequency of the tested clock according to the adjusted calibration code. According to the method, the overall calibration time is effectively shortened, the defects that the calibration speed is low, the number of iterations is large, and the calibration precision is fixed in a traditional dichotomy method are overcome, and the calibration efficiency and flexibility are remarkably improved.

The invention discloses a millimeter wave waveguide transmission loss compensation method, which relates to the technical field of millimeter wave waveguide transmission and comprises the following steps of: monitoring multi-dimensional transmission loss in real time: acquiring electrical parameters such as signal amplitude and phase and parameters such as temperature, humidity and structural deformation to ensure data time synchronization; a loss mechanism layering analysis step: distinguishing three types of loss proportions, and determining dominant factors; a self-adaptive compensation strategy matching step: selecting an exclusive or cooperative compensation mode according to the loss type; a dynamic compensation parameter optimization step: adapting a signal frequency to adjust device parameters; a real-time feedback and fine tuning step: comparing signal quality dynamic correction parameters; and a closed-loop iterative optimization step: constructing a mapping model for iterative updating to form a whole-process closed loop. According to the invention, accurate and efficient compensation of millimeter wave waveguide transmission loss is realized, and signal transmission stability and environment adaptability are improved; the system has quick response and long-term operation reliability, and provides support for large-scale application of the millimeter wave technology.

A frequency multiplier includes an oscillator and a harmonic generator. The oscillator has a resonant cavity and a negative resistance unit. The negative resistance unit includes a feedback capacitor and a parasitic capacitor. The feedback capacitor and the parasitic capacitor collectively provide negative resistance for the resonant cavity. The harmonic generator is configured to generate a harmonic signal based on a fundamental frequency signal taken as input. The oscillator is electrically connected to the harmonic generator, and is configured to receive the harmonic signal, and to output an intrinsic signal with the resonant cavity. A frequency of the intrinsic signal is a multiple of a frequency of the fundamental frequency signal.

The utility model provides a phase-locked loop circuit, which relates to the technical field of phase-locked loops and comprises a reference frequency multiplication filtering unit, an auxiliary mixing frequency-locked phase loop unit and a main mixing frequency-locked phase loop unit. The reference frequency multiplication filtering unit is used for receiving the first reference signal, performing frequency division processing on the first reference signal, performing frequency multiplication filtering on one path of signal after frequency division processing, and outputting a low-phase noise signal; the auxiliary frequency-mixing phase-locked loop unit is used for receiving the low-phase noise signal output by the reference frequency-doubling filtering unit and the other path of signal obtained by frequency division of the reference frequency-doubling filtering unit, and outputting an LO reference signal after frequency mixing and phase discrimination; and the main frequency mixing phase-locked loop unit is used for receiving the second reference signal and the LO reference signal output by the auxiliary frequency mixing phase-locked loop unit, and outputting a coherent signal after frequency mixing and phase discrimination. According to the utility model, the LMX2820 is used as the phase discriminator, the phase detection range is small, the locking detection can be easier, and the practicability is strong.

The invention discloses a vehicle dynamic monitoring and fault early warning method based on machine learning, and relates to the technical field of vehicle operation safety monitoring and intelligent early warning, and the method comprises the steps: S1, carrying out the real-time data collection of the operation state of a key part of a vehicle through a sensor network, carrying out the preliminary filtering processing of a vehicle speed fluctuation value and a road friction coefficient, and carrying out the early warning of the vehicle operation safety monitoring and intelligent early warning; extracting a signal frequency offset and a fluctuation amplitude peak value ratio, and judging abnormal signal fluctuation characteristics in vehicle operation to obtain a preliminary abnormal distribution range; according to the vehicle dynamic monitoring and fault early warning method based on machine learning, full-link linkage from abnormal recognition, risk assessment to dynamic intervention is achieved, vehicle fault early warning is changed from passive prompt to active intervention, and the driving safety, the system stability and the capacity of coping with the complex environment are improved.

To provide a liquid dispensing device that can increase the frequency of the drive signal. [Solution] A capacitive load drive circuit that outputs a drive signal to displace a capacitive load comprises a gate drive circuit that outputs a first gate drive signal corresponding to a modulation signal output by a modulation circuit and a second gate drive signal corresponding to the modulation signal, an amplification circuit that outputs an amplified modulation signal by driving a first transistor driven in accordance with the first gate drive signal and a second transistor driven in accordance with the second gate drive signal, and a demodulation circuit that outputs a drive signal obtained by demodulating the amplified modulation signal, wherein the first transistor and the second transistor contain gallium nitride, and the gate drive circuit, the first transistor and the second transistor are housed in a single package, constituting a semiconductor device, in a liquid dispensing device.

The invention discloses a lithium ion battery overcharge fault early warning identification method based on internal sound characteristics of a battery cell, a storage medium and electronic equipment, and the method specifically comprises the following steps: firstly, collecting a reference sound signal of a battery under an initial or stable working condition, and calculating a reference average frequency; acquiring an original sound signal in the operation process in real time, and calculating an average frequency through short-time Fourier transform by taking a preset time window as a unit after band-pass filtering and self-adaptive noise reduction preprocessing; setting primary and secondary early warning frequency variation amplitude thresholds, and determining critical state parameters by combining internal acoustic signal characteristics of each stage of thermal runaway; and early warning is carried out in real time. According to the method, the grading early recognition of the overcharge fault is realized through the sound signal frequency deviation amplitude, the bottleneck of early warning lag and environmental interference of traditional voltage and temperature monitoring is broken through, special customized equipment is not needed, the deployment cost is controllable, the engineering adaptability is high, and an efficient scheme is provided for battery thermal runaway prevention and control.

The invention discloses a medical signal generation method and system based on a time-frequency double-domain constraint generative adversarial network. According to the method, a multi-category electrocardiosignal generation model is designed on the basis of a conditional generative adversarial network, global attention interaction is carried out by utilizing a learnable potential feature prototype and position-coded signal features through an adaptive neural representation module, and long-distance time sequence dependence of electrocardiosignals is modeled; through the adaptive spectrum sensing module and the dynamic mask mechanism of energy sensing, the discriminator intensifies the discrimination of the consistency of signal frequency domain information while paying attention to the time domain form, thereby effectively inhibiting the non-natural high-frequency artifacts in the generation process, and ensuring the high fitting of the generated signal and the real signal. Experiments show that the fidelity and diversity of generation of various types of electrocardiosignals can be remarkably improved.

To provide a wireless communication signal distribution device that can easily expand the number of signals distributed. [Solution] The wireless communication signal distribution device of the present invention comprises a transmission path for transmitting a first signal, and a plurality of resonators that are not in contact with the transmission path and are spaced apart along the transmission direction of the first signal, and that resonate at the frequency of the first signal, thereby exciting a second signal that has the same frequency as the first signal. The resonators are composed of conductors having a length that causes resonance at the frequency of the first signal.

The invention discloses a frequency increasing centerless building block type CAN bus address automatic configuration method. Adjacent CAN nodes are in butt joint through a CAN bus and input and output pins. Each node detects a frequency value P of an input pin and outputs a periodic square wave signal with a frequency of P + M; cAN bus address configuration results of all nodes in the building block chain are fixed, the address configuration of the first node is 0, and the addresses of the other nodes are progressively increased by 1 along with the sequence of the building block chain; in a CAN configuration program, the input pin signal frequency adopts a cyclic iteration detection mode; the CAN node is designed to be in a function symmetry form after being rotated by 180 degrees, and is expanded and applied to a two-dimensional plane building block type CAN bus framework. According to the method, automatic configuration of the node addresses in the building block type CAN bus architecture can be realized, the address configuration result does not depend on external hardware or software and does not occupy CAN bus communication resources, the main node can be flexibly selected and set by a CAN configuration program, and the method can be conveniently expanded and applied to the two-dimensional plane building block type CAN bus architecture.

The application discloses a kind of real-time short-range near-ground radio transmission loss modeling method and system, it is related to wireless communication technical field, its technical solution main point is: constructing electromagnetic environment perception system, electromagnetic environment perception system includes transmitting antenna unit, receiving antenna unit, environment perception sensor group and data aggregation unit;Under controlled environmental conditions, the reference data of radio transmission loss is collected by electromagnetic environment perception system, wherein controlled environmental conditions include systematically changing the geometric relationship parameters between transmitting antenna and receiving antenna and transmitting signal frequency;Under variable environmental conditions, radio transmission loss data and corresponding environmental information are collected by electromagnetic environment perception system for expansion;Based on the fusion dataset, a data-driven model is used for training to generate a radio transmission loss evaluation model.The application realizes millisecond-level real-time evaluation of near-ground radio transmission loss within 1000m, with low evaluation error.

The present disclosure provides a radio frequency receiving unit and a method of signal reception thereof, in particular, a radio frequency receiving unit is provided. The radio frequency receiving unit comprises a plurality of signal processing paths, at least one receiving port, each of the at least one receiving port being configured to receive a received signal having any frequency within a full bandwidth encompassing a predetermined range of frequencies, a frequency detection unit configured to detect a frequency band to which the received signal belongs, and a control unit configured to control routing, based on the detected frequency band, of the received signal to a corresponding signal processing path for processing.

The invention discloses an aging gait detection method and system based on a millimeter wave radar, and the method comprises the following steps: S10: employing the millimeter wave radar to collect the data of the activities of a human body going up and down stairs; s20, performing Fourier transform on the activity data after sampling to obtain signal frequency spectrum and target distance information; wherein the continuous Chirp signals of which the intervals are fixed values are stored as row vectors, and receiving frequency responses of targets at different distances can be obtained by performing 1D-FFT on each row; performing fast Fourier transform on a plurality of Chirp signals of the same distance unit to obtain target speed information, namely a time-Doppler graph; and S30, constructing a YOLOv11 model, constructing a data set by the time-Doppler maps, carrying out classification training by using the YOLOv11 model, carrying out batch classification prediction on the new time-Doppler maps, and finally outputting the prediction accuracy.

The application provides a dense reservoir fluid identification method based on physical data double driving, comprising: performing abnormal value correction and fluid category direct marking on conventional logging data to obtain labeled logging data; performing signal self-adaptive time-frequency conversion on the labeled logging data, and calculating porosity, permeability and water saturation to output physical prior feature channels; inputting two-dimensional multi-channel time-frequency spectrum and the physical prior feature channels into a pre-constructed MDSC-TAM neural network model to extract hidden logging signal frequency domain spectrum series structure and global sedimentary rule to obtain a dense reservoir fluid identification result; and performing physical perception constraint and decision output on the fusion feature representation to obtain a fluid type and confidence. The application solves the data scarcity and model black box bottleneck, improves the engineering practicability of the algorithm, and realizes high-precision identification of the dense reservoir fluid and enhanced physical interpretability.

A physical quantity sensor assembly, an inclinometer, and a structure monitoring device are provided, offering a technique for correcting nonlinearity in the output signal of the physical quantity sensor without increasing the size of the physical quantity sensor assembly. The physical quantity sensor assembly (1) comprises: a frequency-varying physical quantity sensor (3) whose frequency varies according to the change of the physical quantity; a reference signal oscillation unit (5) that outputs a reference signal; a frequency Δ-Σ modulation unit (10) that generates a frequency Δ-Σ modulated signal by frequency Δ-Σ modulation of the reference signal using an action signal based on the measured signal output by the frequency-varying physical quantity sensor (3); a first low-pass filter (20) disposed on the output side of the frequency Δ-Σ modulation unit (10) and operating synchronously with the measured signal output by the frequency-varying physical quantity sensor (3); and a second low-pass filter (60) disposed on the output side of the first low-pass filter (20) and operating synchronously with the reference signal.

The embodiment of the application provides a parameter inversion method, device and electronic equipment, wherein the parameter inversion method comprises: performing interference suppression on a received incomplete SAR signal to obtain a non-interference signal matrix; wherein the non-interference signal matrix comprises a plurality of non-interference pulse signals with time sequence continuity, and the incomplete SAR signal represents that the SAR signal is incomplete; sequentially performing data processing on each non-interference pulse signal to obtain pulse parameters of each non-interference pulse signal; the pulse parameters at least comprise a stationary phase center position, a termination point, a pulse bandwidth, a pulse signal frequency modulation rate and a peak position; based on the pulse parameters of each non-interference pulse signal, signal parameters of the incomplete SAR signal are inverted to obtain transmission parameters of the incomplete SAR signal; the signal parameters at least comprise a pulse width, a bandwidth, a frequency modulation rate, a pulse repetition interval and a pulse repetition frequency.

A method (1) for operating an ultrasonic flow meter (2) for measuring the flow rate through a measuring tube (4) through which a medium (3) flows is presented and described, wherein the ultrasonic flow meter (2) comprises at least one transmitting ultrasonic transducer (5) for transmitting ultrasonic signals (6) and at least one receiving ultrasonic transducer (7) for receiving ultrasonic signals (6) and a control and evaluation unit (8), wherein the control and evaluation unit (8) controls the transmitting ultrasonic transducer (5) such that it emits the ultrasonic signal (6), the receiving ultrasonic transducer (7) receives the emitted ultrasonic signal (6), and the control and evaluation unit (8) determines at least an indirect value for the flow rate of the medium (3) through the measuring tube (4) by evaluating emitted and received ultrasonic signals (6). Consistent measurement quality is achieved by the control and evaluation unit (8) adjusting an ultrasonic signal frequency (f) of the emitted ultrasonic signal (6) in such a way that a change in the opening angle (phi) of the sound lobe (10) of the ultrasonic signal (6) caused by a change in the value of the speed of sound (v_sos) of the medium (3) is at least partially compensated.