251 results about "Frequency drift" patented technology

The invention discloses a distributed OFDR sensing signal demodulation method and system based on local ridge line tracking, relates to the technical field of optical fiber sensing, and is used for solving the problem that a traditional cross-correlation algorithm is difficult to consider robustness and real-time performance at the same time. The method comprises the following steps: respectively processing a reference beat frequency signal of a sensing optical fiber to be measured in a strain-free state and a measurement beat frequency signal of the sensing optical fiber to be measured in a strain state to obtain a reference complex Rayleigh scattering signal and a measurement complex Rayleigh scattering signal containing a plurality of sensing positions along the optical fiber; calculating a cross-correlation function based on the two signals; stacking the cross-correlation functions corresponding to all sensing positions along a distance domain, and constructing a two-dimensional cross-correlation thermodynamic diagram matrix; performing filtering processing and weighting processing on the two-dimensional cross-correlation thermodynamic diagram matrix to obtain an optimal frequency drift distance; and demodulating based on the optimal frequency drift amount to obtain strain distributed along the to-be-measured sensing optical fiber. According to the invention, high-robustness and rapid demodulation of the signal in an application scene with extremely high real-time requirement can be realized.

The invention relates to the technical field of anti-seismic performance detection, in particular to an anti-seismic performance detection method and system for an assembled steel-wood composite structure, and the method comprises the steps: arranging a multidirectional acoustic emission sensor in a steel-wood structure node area, applying simulated seismic vibration, and synchronously collecting acoustic emission signals; the method comprises the following steps: preprocessing collected acoustic emission signals, dividing the acoustic emission signals into signals corresponding to microcracks and contact slippage, respectively calculating an energy attenuation rate and a phase offset, and constructing a matrix; micro-impact is applied to the steel-wood node through an electromagnetic excitation device, a response signal is collected, resonant frequency is extracted, the drift distance between the resonant frequency and a reference value is calculated, and the severity of interface damage is determined according to the value of the drift distance; the damage correlation index calculation takes the characteristic value of the interface wave propagation characteristic matrix and the resonance frequency drift distance as input, the damage correlation index is calculated through the correlation coefficient, and the damage grade is divided according to the correlation coefficient. And differential characterization of different damage types is realized through the interface wave propagation characteristic matrix.

The invention discloses a multi-channel clock buffer test system and method, and relates to the technical field of electronic testing, and the method comprises the steps: collecting an original waveform data set, synchronizing a unified reference baseline, and generating a clock output data stream; performing frequency domain transformation on the clock output data stream, extracting dominant frequency drift, harmonic intensity change and phase fluctuation, and generating a spectrum disturbance feature vector sequence; performing recursive estimation on the spectrum disturbance feature vector sequence by using a Kalman filter, correcting state distribution in combination with a Bayesian probability updating method, and generating a health score drift trend vector; and performing multi-scale comparison on the health score drift trend vector, and identifying a channel entering a sub-health area by using an abnormal drift acceleration factor to generate an abnormal channel feature data set. According to the method, complex association between historical failure modes and features is mastered through the training time sequence prediction network, potential health score changes and failure time in the future are effectively predicted, and early warning is achieved.

The invention discloses a data processing method and system of a chromatographic instrument, and relates to the technical field of data processing, and the method comprises the following steps: collecting whole-course original detection signals and external interference signs generated in a chromatographic analysis process, carrying out time alignment under a unified time scale, generating an interference rhythm index, and calculating the interference rhythm index; the reference is used as a unified reference for subsequent signal comparison; and based on the interference rhythm index, performing phase drift comparison on the acquired signal, calculating the phase difference between the detection signal and the interference signal, drawing a beat frequency wandering graph, extracting candidate signal segments of pseudo-period interference according to beat frequency change, and generating a pseudo-period candidate segment list. According to the invention, by establishing the interference rhythm index and comparing the interference rhythm index with the phase drift, the time decoupling of the detection signal and the interference signal is realized, and the sampling anti-interference capability is improved; and through dynamic control of a false peak characteristic fingerprint draft and a misjudgment reason table, signal rhythm correction and peak identification optimization are completed, so that the detection accuracy and the data stability are improved.

The invention relates to the field of sensor data processing, and discloses an MEMS drift correction method based on data dynamic sampling and multi-source fusion, and the method comprises the following steps: S1, collecting MEMS three-axis acceleration original data at a first sampling frequency, and synchronously collecting environment temperature, humidity and air pressure data at a second sampling frequency, the first sampling frequency is higher than the second sampling frequency, the basic drift correction model is established by using the low-frequency data to capture the macroscopic and slow-varying relationship between the environmental factors and the drift, then the residual refinement model is established for the high-frequency data, and the high-frequency residual is specially processed; high-frequency drift components related to the environmental change rate are captured, through the two-stage fusion strategy, the accuracy of the model in the macroscopic trend is guaranteed, high-frequency data are fully utilized to improve the instantaneous correction precision, information loss caused by simple downsampling in a traditional method is avoided, and false signals introduced by rough interpolation are also avoided.

The invention discloses a remote monitoring system for a numerical control bearing processing machine tool, belongs to the technical field of machine tools, and solves the problems that during finish turning of a GCr15 thin-wall ferrule, a main shaft pretightening force is attenuated to cause inherent frequency drift, servo parameters just fall on an excitation band, cutting force induces high-frequency flutter, fish scale vibration marks are generated, the service life and noise of a bearing exceed the standard, batch reworking is carried out, and machining efficiency is high. And the precision of a machine tool is permanently damaged. Comprising a multi-source information sensing module, a causal discovery and decision center, a dynamic stiffness field regulation and control module and a real-time simulation verification module, wherein a fiber bragg grating demodulator of the multi-source information sensing module is connected to a main shaft bearing seat in a machine tool through a sensing interface; a laser Doppler vibration meter of the multi-source information sensing module is in butt joint with a tool-workpiece machining area in a machine tool through an optical probe. Pre-tightening-servo-cutting coupling is sensed in real time, the magneto-rheological rigidity is actively adjusted, resonance is avoided, flutter is restrained and eliminated, high-frequency flutter is immune in advance, chatter marks and batch accidents are eradicated, and a cutter machine tool is protected.

The invention discloses a power grid time frequency change trend prediction method and system based on intelligent electric meter data fusion, and the method comprises the steps: measuring the network transmission delay and time deviation between a master clock and a slave clock of a power grid, obtaining an initial time frequency deviation sequence, carrying out the error calibration, carrying out the data fusion after time domain alignment, and carrying out the prediction of the time frequency change trend. Generating a fusion time sequence; performing recursive estimation on the fusion time sequence, outputting an optimal time frequency deviation sequence, and performing synchronous estimation to obtain a clock phase error, a frequency error and frequency drift as state characteristic quantities; and training a preset machine learning prediction model by taking the optimal time frequency deviation sequence as a supervision signal and taking the state characteristic quantity of the corresponding moment as input, and obtaining a prediction result of the power grid time frequency change trend in the future period based on the trained time frequency change trend prediction model. According to the method, the power grid time synchronization precision and prediction capability are remarkably improved, and reliable technical guarantee is provided for stable operation of a power system.

The invention provides a power transmission line operation risk prediction method based on big data mining, and the method comprises the steps: collecting the high-frequency vibration data and environment parameters of a bolt connection part of a power transmission line tower in real time, and generating a time sequence data set containing the vibration frequency, the amplitude and the temperature; a Fourier transform algorithm is adopted for the time sequence data set, a dominant frequency component of the vibration frequency is extracted, linear correction is conducted on the vibration frequency according to the thermal expansion coefficient and the temperature of the bolt material, and a frequency feature set is generated; constructing a bolt state evaluation model according to the preliminary feature set and the stress distribution feature set, evaluating the bolt state, and outputting the bolt pre-tightening force attenuation degree; and according to the state score of each bolt output by the optimized state evaluation model, calculating the overall load sharing and vibration frequency drift degree of the bolt joint, and generating a load sharing feature set.

The invention discloses a low-cost precise time keeping method, system and device based on a gating circulation unit, and relates to the technical field of power grid measurement. The method is executed when the synchronous phasor measurement device cannot receive external signals, and comprises the following steps: monitoring operation parameters which influence the frequency stability of an internal crystal oscillator of the phasor measurement unit in real time; calculating a current frequency error of the crystal oscillator in real time by using a crystal oscillator frequency drift prediction model based on a gated cycle unit network based on the operation parameters; generating a time correction amount according to the current frequency error; and applying the time correction to a local clock of the phasor measurement unit to compensate the frequency drift of the crystal oscillator so as to realize accurate time keeping. According to the invention, through accurate prediction of crystal oscillator errors and lightweight software compensation, the synchronous phasor measurement device adopting a low-cost crystal oscillator can also realize long-time high-precision time keeping, the hardware cost is obviously reduced, and the reliability of power grid monitoring during the Beidou / GPS lock losing period is improved.

The invention discloses a modularized hydraulic system testing system and method, and relates to the technical field of hydraulic testing, and the method comprises the following steps: S1, collecting outlet pulsating pressure signals of a high-pressure plunger pump and a low-pressure vane pump by adopting a nanosecond-level synchronous time mark system, generating a phase residual error map, and calculating a phase residual error map of the outlet pulsating pressure signals of the high-pressure plunger pump and the low-pressure vane pump; the hidden resonance risk is preliminarily judged through frequency drift and amplitude gradient calculation; and S2, on the basis of the synchronous acquisition base line, carrying out cross spectrum coherence degree calculation and phase difference time sequence analysis on the pulsating pressure sequence, identifying a frequency dislocation anchor point, generating a pump source pulsating interference fingerprint, and determining a time window of recessive resonance. According to the method, real-time identification, dynamic intervention and closed-loop control of recessive resonance in the hydraulic system are realized through nanosecond-level synchronous acquisition, phase conjugate inversion and frequency dislocation traction strategies, energy coupling caused by frequency dislocation is effectively avoided, the operation stability and safety of the system are improved, and the service life of equipment is prolonged.

The invention discloses a power distribution area energy storage-photovoltaic oscillation cooperative suppression method based on impedance remodeling, and belongs to the technical field of power system stability control. According to the method, the impedance characteristic of the system is scanned online in real time, the virtual impedance controller parameters of the photovoltaic inverter are dynamically optimized, and the impedance frequency characteristic of the zone area network is actively remodeled, so that the zone area network is always far away from a stable critical point, and oscillation is prevented from occurring from the source. When it is detected that the oscillation energy exceeds the standard, the system immediately triggers the energy storage device to be switched to a virtual synchronous generator mode, phase information of a plurality of energy storage units in a fiber channel synchronization cluster is used, anti-phase damping current opposite to the oscillation trend is injected, and the oscillation energy is rapidly consumed. The invention provides a double-layer suppression strategy based on impedance remodeling and energy storage cooperation, the cooperation of photovoltaic impedance active prevention and energy storage instantaneous suppression is realized, the problem that a traditional fixed parameter damper loses efficacy due to frequency drift is solved, and the operation stability of a high-proportion renewable energy power distribution network is improved.

The invention belongs to the technical field of laser precision machining and control, and particularly relates to a femtosecond laser single-point trigger control system and method based on subnanosecond synchronization, and the method comprises the following steps: S1, building a system synchronization clock locked with a femtosecond laser pulse signal phase; the specific mode of establishing the system synchronous clock is that phase locking is carried out on pulse synchronous signals or frequency division signals output by an internal high-frequency clock source and a femtosecond laser source through a digital phase-locked loop technology, and the low-jitter system synchronous clock which is strictly synchronous with a laser pulse sequence is generated. According to the invention, a system clock locked with a laser pulse phase can be generated through a digital phase-locked loop, and the influence of inherent frequency drift of a laser and circuit delay temperature drift is effectively overcome by combining real-time delay calculation based on a prediction algorithm and a high-resolution DDS delay line technology; the synchronization precision between the triggering moment of the single pulse and the external instruction is stabilized at the subnanosecond level, and the requirement of leading-edge application for the extreme time sequence precision is met.

The invention provides a water supply pipe network leakage detection method and device based on an accelerometer and a readable storage medium thereof, and belongs to the technical field of pipe network detection. The method comprises the following steps: acquiring an original acceleration signal; the acceleration signal is accurately converted into a displacement vibration signal by adopting double-order integral drift suppression processing so as to overcome low-frequency drift; carrying out time-frequency analysis on the displacement signal, and extracting transverse characteristics representing the physical nature of leakage; the transverse characteristic is characterized based on three dimensions of time continuity, frequency broadband and amplitude stability; a self-adaptive threshold value is adopted to judge the transverse characteristics, and the threshold value is dynamically generated according to real-time background noise characteristics; and finally, multi-dimensional comprehensive judgment can be carried out by combining time domain auxiliary conditions such as a peak factor and a zero-crossing rate, and a leakage result is determined. The problems of integral drift, inaccurate feature extraction and poor robustness are solved, and low-cost, high-precision and low-false-alarm leakage detection is realized.

The invention relates to the technical field of radio orientation, and discloses an unmanned aerial vehicle radio frequency countering monitoring system based on multi-source signal state perception, and the system comprises a radio frequency collection subsystem which employs a dual-channel common-source difference mechanism to synchronously collect target and reference signals; the state synchronous bus obtains a motion state vector of the unmanned aerial vehicle; and the virtual aperture synthesis processor calculates an instantaneous phase difference between channels to offset local frequency drift, generates a correction phase sequence, constructs a virtual antenna array model in combination with a motion trail, and solves a target space incident angle. And high-precision direction finding of long-wave signals is realized on a small platform.

The invention provides a resonance control method for an excimer lamp driven by a steep pulse edge, and relates to the technical field of molecular lamps. The resonance control method of the excimer lamp driven by the steep pulse edge comprises the following steps: S1, based on a dielectric barrier discharge equivalent circuit model, adopting a fast Fourier transform spectrum analysis method, measuring fundamental wave impedance characteristics of an LC resonance network through an impedance analyzer, establishing a transfer function containing parasitic parameters: Z (s) = [sLr + 1 / (sCr)] Rarc, and generating an initial resonance parameter set; by establishing a transfer function model containing parasitic parameters, combining fast Fourier transform spectrum analysis and accurately extracting fundamental wave impedance characteristics, the problem of resonance point offset caused by neglecting the parasitic parameters in a traditional method is solved, the precision of an initial resonance parameter set is improved, real-time phase difference data are identified on line by using a recursive least square method, and the real-time phase difference is obtained. Resonant frequency changes are dynamically tracked, frequency drift errors are compensated, resonance point tracking precision is controlled within + / -0.1%, and invalid discharge energy loss is remarkably reduced.

The invention is suitable for the technical field of electric energy transmission, and provides an SWPT system frequency adaptive regulation and control method and system based on environmental perception, and the method comprises the steps: obtaining the output current data of high-frequency electric energy, and obtaining the first current data; determining an initial frequency disturbance step length in combination with the collected environmental parameters; applying disturbance to the output frequency according to the initial frequency disturbance step length, and collecting output current data after disturbance to obtain second current data; the change trend of the two current data is analyzed, and the deviation direction of the current working frequency and the system resonant frequency is judged; adjusting the output frequency according to a frequency control instruction generated in the deviation direction, and enabling the current working frequency to approach the resonant frequency; current data is continuously updated, and in combination with environment parameters collected in real time, the working frequency tracks resonant frequency drift caused by environment change through iteration; and the environmental adaptability, the energy transmission efficiency and the overall reliability of the single-line electric energy transmission system are effectively improved.

The invention discloses an unmanned aerial vehicle countering method and system based on multi-platform cooperation, and relates to the technical field of unmanned aerial vehicle countering, and the method comprises the steps: carrying out the data collection based on a multi-unmanned aerial vehicle platform, including radio frequency signals, radar scanning and image data; and extracting a motion feature vector, calculating instantaneous frequency drift according to instantaneous frequency fluctuation, analyzing and calculating distortion deviation through a radio frequency signal, and fitting a response curve of the power amplifier through a logarithmic power curve. According to the method, through joint characterization of constellation diagram distortion and a power amplifier response curve, the distinguishing capability of radio frequency characteristics is enhanced, the omnibearing characterization capability from signal waveform details to power degradation behaviors is provided, and through a closed-loop mechanism of coupling characteristics, abnormal point detection and position inversion, the power degradation behavior of the power amplifier is improved. The real-time performance and precision supported by the countering decision are remarkably enhanced, the abnormal analysis of sample points is directly linked to target space positioning, and target position estimation is gradually optimized.

The invention relates to the technical field of ultrasonic bonding, in particular to an ultrasonic adjusting method of a bonding system, which comprises the following steps of: acquiring voltage and displacement waveforms, analyzing a power trend, shielding a main window if a rising proportion is high and displacement exceeds a limit, extracting a maximum displacement point frequency to divide a standby window, and generating standby configuration by combining an impedance library. And monitoring peak time difference fluctuation and offset, calling configuration and matching a displacement time sequence generation instruction, monitoring displacement stability to be matched with pressure, setting a standby window as a main window if the condition is met, and generating a reconstruction mark. According to the method, the driving voltage and the transducer displacement waveform are continuously monitored, the power trend and the displacement fluctuation are analyzed in real time, the peak time difference fluctuation is synchronously monitored, the abnormal working conditions are screened to trigger the driving strategy switching, and the main frequency band is reconstructed according to the steady-state displacement characteristics. Pseudo soldering and material damage are avoided, the vibration energy utilization rate is improved, and the bonding pressure control precision and the connection strength are guaranteed.

The invention relates to the technical field of array antenna signal integrity detection, and discloses an array antenna signal integrity deception detection method and system, and the method comprises the steps: obtaining a receiving signal in an array antenna, and analyzing the quality parameter of the receiving signal; according to the quality parameter, identifying a receiving unit with inherent signal bias in the array antenna, and marking the receiving unit with inherent signal bias as a special processing unit; for a special processing unit, establishing and continuously updating a defect feature model representing inherent signal bias of the special processing unit under the condition of no deception signal; inherent signal bias is eliminated from the real-time received signals of the special processing unit based on a defect feature model, and signals after bias elimination are obtained; detecting whether an abnormal phase or frequency drift exists in the signal after the offset is eliminated; and when the detected abnormal phase or frequency drift exceeds a preset spoofing judgment threshold, determining that a spoofing attack exists. The problem that spoofing attacks are difficult to recognize is effectively solved.

The invention provides a method and equipment for testing the punctuality precision of a time synchronization device, belongs to the technical field of time frequency, and aims to solve the problems of low test automation, difficulty in quantification of environmental influence, inaccurate evaluation and high result subjectivity in the prior art. The method comprises the following steps: simulating an external signal interruption punctuality scene through a dual-channel radio frequency switch, and synchronously acquiring an output signal (time deviation data compared with a high-precision reference clock) of a time synchronization device and temperature, humidity and air pressure environment data; and analyzing the stability of the crystal oscillator through a TIE algorithm and Arron variance, and correlating modeling to quantify the environmental influence to generate a multi-dimensional evaluation report. The objective performance portrait containing parameters such as frequency drift and stability is provided, the defects of a traditional method are overcome, and a scientific basis is provided for equipment research and development optimization and model selection design.

Piezoelectric materials, particularly ones with high quality factor used for mechanical antenna implementations, are sensitive to environmental conditions including temperature swings, humidity, vibration. Under the varying environmental conditions, the resonant frequency of the piezoelectric antenna can drift, and this results in the dampened piezoelectric radiator performance due to the mismatch between RF source' excitation frequency and piezoelectric antenna's resonant frequency. The frequency drift can be detrimental to the operation of the communication system that involves piezoelectric transmitter / receiver as a system component. In embodiments, the piezoelectric antennas may be integrated into a crystal oscillator to lock a drive frequency of the piezoelectric antennas to a resonant frequency of the piezoelectric antennas.

The present application relates to bolt state monitoring technical field, disclose a kind of embedded wireless passive bolt tightness state monitoring method based on surface acoustic wave technology, specifically includes the following steps: based on the real-time acquisition frequency drift amount of surface acoustic wave resonator, and the looseness risk of bolt is judged in real time, generates looseness warning signal and safety signal;Based on warning signal, the frequency drift amount before generating warning signal is analyzed at change rate, and the change rate degree is judged;Based on the change rate degree judging result, the time point when frequency drift amount reaches frequency drift amount risk value is predicted.The present application can judge bolt looseness risk in real time, generates warning signal in time when bolt appears looseness sign, reminds relevant personnel to pay attention to bolt state, avoid bolt looseness further development and not be perceived, to reduce the possibility of equipment failure, accident.

This invention relates to the field of precision mechanical control technology, specifically to a method based on a magnetoelectric converter and linearity control. The method includes: acquiring raw magnetic induction data through a magnetoelectric converter; obtaining a three-dimensional magnetic field distribution through electromagnetic field spatial mapping and extracting the axial gradient vector field; constructing a virtual magnetic streamline model based on this to identify local disturbance regions where magnetic field distortion exceeds a threshold; performing multi-scale time-frequency analysis on the data in this region to separate high-frequency fluctuations caused by mechanical vibration and low-frequency drift components caused by thermal deformation; inputting the two components into a cross-coupled compensation decision network to generate high-frequency suppression commands and low-frequency compensation trajectories, which are then merged to form a comprehensive drive signal for compensation. This method can accurately locate the source of linearity disturbance and perform targeted decoupling control of errors from different physical sources, improving control accuracy and stability under complex operating conditions.

This invention discloses an AI-based spectral monitoring and early warning system and method for performance degradation of key power supply components, relating to the field of power supply component performance monitoring technology. The system includes the following steps: Under high-temperature, high-carrier excitation conditions, a phase-continuous mapping field characterizing nonlinear interactions is generated by establishing a time-frequency coherent baseline of multi-source signals and injecting micro-amplitude phase perturbations; a cross-scale energy differential inversion chain is constructed based on this mapping field to extract energy residuals and identify transient energy aggregations; a dynamic pseudo-peak constraint chain is formed through envelope self-reflection calibration; further, time-frequency drift correction and dynamic weight refeedback are performed to generate an adaptive health matrix; finally, the energy spectrum is topologicalized, and continuous monitoring and intelligent early warning of degradation risks are achieved based on topological perturbations. This invention achieves proactive identification and intelligent early warning of power supply component degradation by dynamically fusing energy and phase characteristics through time-frequency drift correction and the topological health matrix, thereby improving the accuracy of performance degradation monitoring for key power supply components.

A circuit for reducing a temperature-induced frequency drift in a voltage to current (V2I) converter based voltage-controlled oscillator (VCO) for at least one wide band phase-locked loop (PLL), the circuit includes a V2I resistor node of the V2I converter, the V2I resistor node being at one end of a resistor, the VCO, and a current controlled oscillator (CCO), and the circuit is configured to provide a fixed offset current to the V2I resistor node to cause at least one V2I output current to have a value conversely proportional to absolute temperature (CTAT), the at least one V2I output current being output by the V2I converter, and mirror the at least one V2I output current to the CCO to reduce the temperature-induced frequency drift at a lower frequency band of the VCO.

This invention discloses a wireless, passive, and visualized cerebrospinal fluid drainage tube flow monitoring sensor, system, and fabrication method, belonging to the field of biomedical sensing and microelectromechanical systems (MEMS) technology. It includes a flexible substrate, an interdigital capacitor-open resonant ring structure disposed on the substrate surface, and a microchannel pressure conversion structure bonded to it; the microchannel corresponds vertically to the position of the interdigital capacitor. The pressure generated by the cerebrospinal fluid flow drives the displacement of the liquid metal, modulating the equivalent dielectric constant of the interdigital capacitor and causing a resonant frequency shift. The frequency drift is wirelessly read by an external device, and the flow rate is calculated using an algorithm, achieving passive wireless continuous monitoring. This invention, employing the aforementioned sensor, system, and fabrication method, solves the problems of high infection risk, low accuracy, and inability to continuously monitor existing drainage monitoring methods that rely on manual observation or wired sensors. It has the advantages of high sensitivity, flexible integration, and good safety.

The application provides an electronic watch running time precision regulation system, and relates to the technical field of data processing.The system is used for collecting temperature values, voltage values and cumulative running time, counting the number of pulses output by a crystal oscillator in a unit time, obtaining state data and basic frequency data, calculating frequency offset values in different periods, performing window sliding, calculating drift trend values in different windows, calculating the difference between different states between adjacent periods, obtaining state change values, combining and analyzing the state change values with a frequency drift trend sequence, obtaining a state response coefficient set, identifying effective disturbance components in state change vectors of different periods, calculating pulse compensation values in different periods, obtaining pulse compensation data, correcting timing pulses, obtaining a pulse output sequence, and updating the time of the electronic watch according to the pulse output sequence.The application can regulate the pulse signal of the electronic watch and ensure the precision of running time.

The invention provides a temperature self-adaptive frequency locking system and method applied to a CPT atomic clock, the system comprises a TEC heating sheet 1, a VCSEL laser 2, a temperature sensor 3, a gas chamber shell 4, a gas chamber 5 and the like, the VCSEL laser 2 is tightly attached to the surface of the TEC heating sheet 1, the temperature sensor 4 is arranged near the outer side of the gas chamber 5, the gas chamber 5 is wrapped by the gas chamber shell 4, and the TEC heating sheet 1 is arranged in the gas chamber shell 4. A heating resistor network 7 is arranged at the lower part of the air chamber 5; a laser beam emitted by the VCSEL laser 2 passes through the gas chamber 5 and then is received by the photoelectric sensor 6. The whole control is executed by a CPT atomic clock control system 9; and feedback signals of the temperature sensor 4 are respectively transmitted to the frequency drift algorithm processing module 10 and the control parameter adjustment algorithm processing module 11. Output signals of the two modules are transmitted to a CPT atomic clock control system 9; a feedback signal of the photoelectric sensor 6 is also transmitted to the CPT atomic clock control system 9; the VCO voltage-controlled crystal oscillator 8 is controlled by the CPT atomic clock control system 9 and outputs frequency to the outside.

The application discloses a Helicobacter pylori breath test signal denoising fitting method and system, and belongs to the technical field of medical detection and signal processing. The method processes the continuous monitoring signal of the 13CO2 / 12CO2 isotope ratio in exhalation: firstly, the original signal is subjected to band-pass digital filtering to suppress high-frequency noise; then, low-frequency drift is eliminated through adaptive baseline correction to generate a drift-removed signal; subsequently, a robust peak value recognition algorithm is used to extract physiological response characteristics; finally, the identified peak value is taken as the center, a nonlinear function with physiological constraints is used for local fitting, and the Delta Over Baseline value is calculated based on the generated fitting curve with high precision. The application effectively solves the signal distortion problem caused by breathing fluctuations, instrument noise and the like in in vivo detection, realizes high-fidelity restoration of the Helicobacter pylori metabolic response, and significantly improves the detection accuracy and reliability of the breath test.

The invention relates to the technical field of bulk acoustic wave resonators, and particularly provides a bulk acoustic wave resonator and a preparation method thereof.The resonator comprises a first substrate, a coating type structure film layer, a bottom electrode, a piezoelectric layer and a top electrode which are sequentially connected from bottom to top, an acoustic reflector is arranged on the coating type structure film layer, a temperature compensation layer is arranged in the bottom electrode, and the piezoelectric layer is arranged on the top electrode; the temperature coefficients of the bottom electrode, the piezoelectric layer and the top electrode are all opposite to the temperature coefficient of the temperature compensation layer; the resonator can effectively restrain resonant frequency drift generated by the bottom electrode, the piezoelectric layer and the top electrode.