1414 results about "Filter (signal processing)" patented technology

The present invention relates to the technical field of monitoring, in particular to a remote monitoring method and system for an aviation obstruction light. The method comprises the following steps: on the basis of an external sensor, acquiring electromagnetic signals sent by an aviation obstruction light; and by means of using a signal processing algorithm, processing the obtained original signals to eliminate noise interference and standardize the signal format, so as to generate signal-purified data. Using a support vector machine and a random forest algorithm in the present invention enhances the fault mode identification capability and the accuracy of predicting device performance degradation trends, and substantially improves the reliability of fault prediction; the combination of a Kalman filter and a multi-level decision tree provides powerful support for the integration and analysis of multi-source data, thereby ensuring the comprehensiveness and effectiveness of decision-making support information; and using a self-organizing map network and U matrix visualization technology not only shows advantages in the aspects of data mode identification and anomaly detection, but also improves the interpretability of data analysis by means of visual image displaying.

The invention discloses a power supply real-time compensation technology and application based on digital signal processing, and relates to the technical field of power electronics, and the power supply real-time compensation technology comprises a split-phase parallel processing architecture: a three-phase independently configured DSP core, each core integration comprises a real-time harmonic detection module, a dynamic sliding window FFT-RT algorithm is adopted, and the window length is adjustable in a set range; the bandwidth of the self-adaptive variable parameter filter can be dynamically adjusted in a set range; the FPGA coprocessor is specially used for PWM generation; an input stage of the harmonic prediction and decomposition module is synchronously acquired by a multi-source sensor; the processing layer comprises an improved VMD decomposition unit and a variational mode decomposition order; the edge prediction network is used for deploying a lightweight LSTM model, embedding a DSP core and predicting a harmonic spectrum in a future short period; and the multi-target dynamic optimization layer is used for setting a dynamic weight distributor and performing real-time adjustment according to the load sudden change rate. According to the invention, through split-phase parallel architecture, harmonic prediction and dynamic optimization, the response speed, multi-target cooperation and reliability improvement in the field of power supply real-time compensation are realized.

The invention discloses a calibration system in an active channel of a waveguide array phased-array antenna, and relates to the technical field of calibration in the active channel. Comprising a calibration judgment module, a waveguide directional coupling module, an amplitude-phase detection module and a digital domain optimization module, the calibration judgment module realizes intelligent triggering calibration through real-time monitoring of a multi-dimensional environment and performance parameters, and ensures that a calibration process is started only when the system state is deteriorated; the waveguide directional coupling module ensures that the calibration signal is accurately injected into each channel, and realizes cross polarization suppression through a polarization grid filter; the amplitude-phase detection module realizes high-precision measurement of amplitude, phase, group delay and polarization parameters of feedback signals of each channel by using superheterodyne and IQ demodulation technologies; and the digital domain optimization module calculates and updates the complex compensation weight of each channel through real-time digital signal processing and a self-adaptive algorithm, and realizes comprehensive and accurate calibration in combination with temperature-frequency interpolation and nonlinear pre-distortion compensation.

The invention relates to the technical field of anti-interference, in particular to a communication signal interference elimination method and system, and the method comprises the following steps: obtaining communication signal time domain data, calculating a signal energy change rate, a signal abrupt change rate and a phase drift rate, marking and distinguishing a signal region according to a calculation result, and obtaining a communication signal non-stationary interval identification result. According to the method, the time domain data of the communication signal is subjected to fine-grained calculation, and the signal energy change rate, the signal abrupt change rate and the phase drift rate are extracted, so that accurate signal region distinguishing is realized, the regression modeling parameter range is adjusted, the influence of instantaneous data of an abrupt change region is reduced, and the stability of signal reconstruction is improved; according to the method, signal-to-noise ratio calculation and interference power fluctuation amplitude evaluation are combined, channel state parameters are dynamically adjusted, interference intensity evaluation is more accurate, the filtering step length, the weight coefficient and the gain coefficient are optimized based on error information, signal processing adapts to different types of interference, and integrity and stability of communication signals are enhanced.

The invention belongs to the technical field of signal acquisition and processing, and discloses a low-noise biopotential signal acquisition system and a low-noise biopotential signal processing method. An original bioelectricity signal of a human body is collected through an electrode array, and analog-to-digital conversion is carried out after the signal is processed by a multi-stage self-adaptive filtering and amplifying circuit. A digital signal is sequentially subjected to adaptive wavelet transform denoising and empirical mode decomposition to obtain a multi-level intrinsic mode function set, an intrinsic mode function of a characteristic frequency band is extracted from the multi-level intrinsic mode function set, and the signal is reconstructed. Introducing a dual noise reduction mechanism combining adaptive wavelet transform and empirical mode decomposition; a signal quality real-time evaluation system is established, and system parameters including the gain of a variable gain amplifier and the bandwidth of a dynamic band-pass filter are dynamically adjusted through closed-loop feedback. The self-adaptive optimization of the whole biopotential signal acquisition process is realized, various interferences are effectively inhibited, the signal characteristics are reserved, and the signal-to-noise ratio is remarkably improved.

A system and method are disclosed for low-light image enhancement using hierarchical adaptive wavelet decomposition with cross-scale feature fusion. The system analyzes a raw input image to determine image characteristics and preprocessing parameters. A hierarchical adaptive wavelet decomposition process creates a variable-depth decomposition tree comprising frequency domain nodes, with decomposition depth determined by local image complexity. Cross-scale feature fusion implements attention mechanisms between nodes at different decomposition levels, enabling bidirectional information flow across scales. A dynamic network pool allocates specialized neural networks to process nodes based on their frequency characteristics, with weight sharing between similar nodes for efficiency. An adaptive reconstruction engine traverses the decomposition tree using learned filters and multi-scale residual learning to produce an enhanced image. The hierarchical approach enables superior low-light image enhancement by allocating computational resources based on content complexity, achieving better quality than fixed decomposition methods while maintaining compatibility with existing image signal processing pipelines.

The invention relates to the technical field of voice processing, in particular to a mixed voice processing method, electronic equipment and a computer readable medium. The method comprises the following steps: collecting mixed voice and environment influence parameters; carrying out bionic frequency domain analysis on the mixed voice to obtain low-frequency attenuation compensation characteristic data; performing multipath effect propagation analysis on the low-frequency attenuation compensation characteristic data through the environmental influence parameters to generate channel distortion data; performing time domain-frequency domain joint deconvolution processing on the mixed voice by using the channel distortion data to generate a direct sound component and a reflected sound component; performing adversarial training based on the direct sound component and the reflected sound component to generate anti-multipath speech enhancement data; and constructing a dynamic frequency compensation filter based on preset environmental acoustic characteristics. Through the multi-stage signal processing, frequency compensation and real-time optimization technology, the output quality of the mixed voice is improved.

An adaptive variable step-size LMS filter based on a hyperbolic tangent function and its filtering method and computer equipment belong to the field of filter technology, and solve the problem that the LMS algorithm improved based on a nonlinear function requires too many manual adjustments of parameters and that the convergence speed and convergence accuracy of the traditional LMS algorithm cannot be satisfied simultaneously. The method of the present invention includes: determining the filter tap length and the number of iterations; initializing the filter parameters; obtaining the filter input signal vector; determining the instantaneous expected signal of the filter; obtaining the instantaneous output signal; obtaining the instantaneous error signal of the filter and the accumulated amount of the error signal based on the instantaneous output signal; obtaining the instantaneous step size using a step-size update formula based on a hyperbolic tangent function; and continuously iterating the filter tap weight coefficient vector to construct an LMS filter using the filter tap weight coefficient vector obtained after the number of iterations. The present invention is suitable for improving the performance of the LMS filter, and the filter of the present invention can be widely used in various signal processing fields.

The invention relates to a digital lock-in amplifier based on a frequency adaptive technology and a weak signal acquisition system and method, and the system comprises a front-end signal processing module which is used for obtaining a weak signal to be detected; the frequency self-adaptive tracking module is used for performing fast Fourier transform on the frequency of the weak signal to be measured to obtain the position of the maximum spectral line so as to synthesize a frequency control word, further generate a local reference signal and simultaneously adjust the coefficients of a low-pass filter and a loop filter and the series adjustment mode of a carrier synchronization ring; the multi-rate narrow-band low-pass filter module is used for multiplying the digital signal by a local reference signal and then carrying out filtering and down-sampling on a high-frequency signal to obtain a plurality of mutually orthogonal difference frequency components; the vector operation module is used for carrying out vector operation on the plurality of mutually orthogonal difference frequency components to obtain the phase and the amplitude in the weak signal to be measured; and the man-machine interaction module is used for displaying and storing the phase and the amplitude in the weak signal to be detected.

The invention relates to a method for reducing the effects of noise suppression on the measurement of the phases of satellite navigation signals at the point of their reception, wherein, in the method, a one-dimensional or multi-dimensional antenna array is provided with multiple reception antennas, satellite navigation signals received by the reception antennas are processed in a signal processing unit, the received satellite navigation signals undergo noise suppression in the signal processing unit by means of a spatial filter, i.e., by means of spatial filtering, for example by a power inversion (PI) filter or a projection filter, and after the noise suppression by means of the signal processing unit, the carrier phase of at least one or each satellite navigation signal is determined and is corrected by calculating parameters of one or more eigenbeamformers.

The invention discloses an automatic control method and system for a bias point of a photoelectric modulator, and relates to the field of signal processing, and the method comprises the steps: generating a composite disturbance voltage signal through a digital signal processor; the bias electrode is injected into the photoelectric modulator and used for collecting the optical signal output by the photoelectric modulator and converting the optical signal into an electric signal; extracting a fundamental component amplitude and phase difference data of a second harmonic component, a third harmonic component and a fundamental wave; dynamic characteristic parameters are calculated through spectral analysis, and the mapping relation between the characteristic parameters and the offset of the offset points is established; outputting the offset direction and the offset level of the offset point through a deep learning model; a bias voltage compensation amount is generated through a fuzzy PID (Proportion Integration Differentiation) controller; and adjusting the bias electrode voltage, smoothing the filter, and eliminating high-frequency jitter. The method has the advantages that high-precision and stable bias point adjustment is realized through the composite disturbance signal, real-time spectrum analysis and deep learning optimization decision in combination with fuzzy PID control and a dynamic closed-loop mechanism, and the system performance and stability are remarkably improved.

The invention relates to the technical field of particle accelerators, in particular to a transverse feedback system with a switchable excitation direction and a control method thereof, and the system comprises a beam position detector BPM which is used for measuring a beam signal; the RF front end is used for receiving the beam signal sent by the beam position detector BPM and carrying out amplification and filtering processing; the ADC module is used for converting the beam signal into a digital signal; the digital signal processing module is used for carrying out digital signal processing calculation to obtain an excitation signal; the DAC module is used for carrying out digital-to-analog conversion; the power divider is used for adjusting the phase of the excitation signal; the exciter comprises four Kickers with electrodes, a power amplifier, a low-pass filter and a matched load and is used for applying a transverse excitation signal to the beam current, and the problems that in the prior art, a transverse feedback system Kicker occupies a large longitudinal space, the system is complex, and precision and efficiency are low are solved.

The invention discloses a high-throughput satellite communication terminal system, which comprises a radio frequency channel unit, a signal processing unit, a terminal processing unit, a power supply management unit and an anti-electromagnetic interference module, and is characterized in that the radio frequency channel unit carries an agile device and a power amplifier and is used for realizing bidirectional conversion between a baseband signal and a radio frequency signal; communication frequencies of a Ka frequency band, a valley value of 5GHz and a peak value of 40GHz are supported, a zero intermediate frequency receiver structure is adopted, image frequency interference is eliminated through one-time frequency conversion to a baseband, and a high-integration design that a radio frequency signal directly enters a frequency mixer after passing through an antenna, a radio frequency filter and a low-noise amplifier is realized. According to the high-throughput satellite communication terminal system, the coverage problem of traditional communication in a blind area of a power grid is solved, safe, efficient and stable transmission of power data is realized, the emergency communication capability and the equipment environment adaptability are remarkably improved, and key technical support is provided for constructing global visual monitoring and intelligent scheduling of the digital power grid.

The invention belongs to the technical field of underwater acoustic engineering and digital signal processing, and particularly relates to a fractional delay FIR (Finite Impulse Response) phase calibration method and system of a multichannel sonar system. Comprising the steps of signal acquisition and reference channel selection; high-precision relative delay estimation; calculating a cross-correlation function of other channel signals and the reference channel signal, performing coarse estimation by searching a peak point of the amplitude of the cross-correlation function, and performing fine estimation on the peak position by using a parabola interpolation method to obtain the delay time of each channel relative to the reference channel; designing an FIR fractional delay filter; digital filtering and phase calibration; verifying a calibration effect; and calculating the phase of each channel signal at the target frequency point after calibration, and counting the standard deviation of each channel signal so as to evaluate the improvement degree of phase consistency. The method aims at overcoming the defect that traditional integral multiple sampling delay correction precision is insufficient, high-precision phase compensation of a sub-sampling point level is achieved, and therefore the performance of algorithms such as beam forming of a multi-channel sonar system is remarkably improved.

The invention discloses a rotor unbalance rapid adjustment method based on Kalman filtering, and belongs to the technical field of rotor dynamic balance. According to the method, a rotor rotating speed signal is obtained through a magnetic encoder, and a piezoelectric vibration sensor is triggered to collect a radial vibration signal. In the aspect of signal processing, a zero phase shift filter is adopted to remove noise interference, and an initial phase and an amplitude are extracted by using FFT (Fast Fourier Transform). And calculating a rotating speed change rate based on the sliding time window, and judging whether the rotor is in a steady-state or transient-state working condition. Under the transient working condition, a state space model containing amplitude, phase and rotating speed is constructed, and unbalance adjustment parameters are predicted through Kalman filtering recursion; and under a steady-state working condition, accurately calculating a correction parameter by adopting a least square method. In addition, a least square fitting model based on a sine function is constructed, amplitude estimation is optimized, and the unbalance calculation precision is improved. According to the invention, the unbalance of the rotor can be quickly and accurately adjusted, and the stability and the service life of a rotating system are improved.

The invention provides a multiphase filtering sampling method suitable for satellite communication. The method comprises the following steps: receiving an original modulation signal and converting the original modulation signal into a digital signal sequence; extracting a signal feature vector and generating a processing configuration parameter; performing orthogonal decomposition to generate I / Q signal pairs and performing oversampling; initializing a multi-phase filter and generating an optimal filter coefficient; carrying out phase calibration and filtering; determining an interpolation coefficient and executing multi-stage integer interpolation and mixed precision fractional interpolation; configuring a dynamic cache system; phase reordering and synthesis are executed; spectral analysis is performed and optimization parameters are generated. According to the invention, high-precision signal processing is realized, the adaptive capability and the efficient resource utilization characteristic are realized, and the performance of a satellite communication system is remarkably improved.

The invention relates to the technical field of biomedical signal processing, and discloses a multi-wavelength PPG signal motion artifact elimination algorithm and system. The method comprises the following steps: acquiring a multi-wavelength PPG signal by using acquisition equipment; inputting the acquired noise-containing multi-wavelength PPG signal into a filter; the filter processes an input signal and then generates a denoised PPG signal; extracting a period of the denoised signal in real time by using an autocorrelation function; inputting the denoised PPG signal and a period extracted in real time into a BSS algorithm to find an optimal noise reference signal; taking the denoised PPG signal and the optimal noise signal as a first input and a second input of adaptive filtering to eliminate motion artifacts; the motion artifacts are eliminated by using the algorithm, and finally the PPG signals with the motion artifacts eliminated are output; the method overcomes the problems of dependence on additional hardware, low correlation of noise reference signals, complex algorithm and the like in the prior art.

The invention discloses a periodogram and incoming wave direction finding fused multi-unmanned aerial vehicle signal identification method and system, and relates to a signal processing technology, and the method comprises the steps: obtaining to-be-identified signals with time domain aliasing and frequency domain non-aliasing; suppressing the noise of the to-be-identified signal by using an average periodogram method and smooth filtering, and calculating a bottom noise value; according to the calculated bottom noise value, setting a judgment threshold to detect a target unmanned aerial vehicle signal; estimating the start-stop frequency and bandwidth of the detected target unmanned aerial vehicle signal; performing signal separation by using an FIR filter according to the estimated starting and ending frequency and bandwidth; and executing incoming wave lateral direction based on the separated target unmanned aerial vehicle signal so as to complete signal identification. According to the method, unmanned aerial vehicle signal detection is completed through an average periodogram method, unmanned aerial vehicle weak signals which are sparsely distributed in space are further obtained through a direction finding method, and weak signal unmanned aerial vehicles which are far in distance are detected.

The invention relates to an ultralow-delay visual positioning system and method based on an event camera. The system comprises an event sensing module, an inertial measurement unit (IMU) and a mixed signal processing unit. The event sensing module has a microsecond-level response characteristic and is integrated with a dynamic bias adjustment and tunable optical filter; the IMU is rigidly connected with the IMU, and the physical center alignment error is less than 0.5 degree; and the hybrid processing unit adopts an FPGA (Field Programmable Gate Array) and ARM (Advanced RISC Machines) collaborative architecture to realize event filtering, time synchronization, motion compensation and tight coupling optimization. According to the method, an event brightness residual error and an IMU pre-integration residual error are combined to construct a joint cost function, a sliding window is dynamically adjusted based on event entropy, and loop-back and closed-loop correction is realized through mutual information criteria. The method can realize six-degree-of-freedom pose estimation as high as 500Hz, has the advantages of low delay, high precision, high robustness and the like, and is suitable for high-speed scenes such as unmanned aerial vehicles, AR navigation, industrial robots and the like.

The invention discloses an autonomous positioning method of an unmanned system based on integration of microwave distance measurement and inertial navigation, and belongs to the field of application of a cross technology of navigation positioning and signal processing. In an unmanned system, a filter is tightly combined with an inertial navigation system and a microwave distance measurement positioning system and is regarded as a navigation positioning system, a motion track of a target carrier is calculated, and a sensor observation model fusing two independent inertial navigation systems of inertial navigation and micro navigation in the navigation positioning system is constructed; the method comprises the following steps of: reflecting an interference result of a microwave signal and a reference signal by a solid-state spin detection object, and performing FFT (Fast Fourier Transform) on each reflected microwave signal after frequency mixing to finish microwave distance measurement; on the basis of forming distance calculation, position results output by a distance measurement positioning algorithm are fused, random errors of the system are compensated by adopting an error compensation algorithm, errors of the inertial navigation system are corrected, covariance is updated and corrected according to an observation matrix and Kalman gain, and intelligent autonomous control positioning of the system is realized.

The invention discloses an electroencephalogram signal processing method and system based on motion artifact prediction. The method comprises the following steps: acquiring experimental electroencephalogram data when a testee executes a motion imagination task; discrete wavelet transform is carried out on experimental electroencephalogram data, and signals are decomposed into low-frequency components and high-frequency components through a low-pass filter and a high-pass filter; inputting the low-frequency component into a pre-constructed and trained ARIMA model, and predicting to obtain a linear artifact; inputting the high-frequency component into a pre-constructed and trained XGBoost regression model, and predicting to obtain a nonlinear artifact; combining the linear artifacts and the nonlinear artifacts to generate a complete artifact prediction signal; real electroencephalogram signals are separated through difference value calculation of the experimental electroencephalogram data and the artifact prediction signals. According to the method, the time sequence change of the motion artifacts is predicted by utilizing the ARIMA model, and the nonlinear artifact features are captured in combination with the XGBoost regression model, so that the motion artifacts can be effectively removed, and purer electroencephalogram signals can be recovered.

The invention discloses a circuit and a method for ultrasonic flow detection, the method is a signal processing method, a system main controller is provided with a double-path driving channel and a double-path ADC acquisition channel, and a switching circuit and a signal conditioning path are dynamically controlled by a microcontroller, so that the flow of ultrasonic flow is detected. Through a real-time noise correction and self-calibration mechanism running in parallel with signal acquisition, a circuit system comprises a microcontroller, a switching circuit A1, a switching circuit A2, a driving signal conditioning circuit, a receiving signal conditioning circuit, a band elimination filter circuit and ultrasonic probes Y1 and Y2, multi-channel cooperative work and error compensation are realized; through a two-way switching architecture, a switching strategy and a dynamic calibration mechanism, the problems of zero drift accumulation, environmental noise interference and difficult calibration circuit signal deviation existing in a traditional single-channel design are effectively solved, and the precision, stability and environmental adaptability of flow measurement are remarkably improved.

The invention discloses a self-adaptive rotating baseline direction finding method, device and equipment, a medium and a terminal. Signals are continuously collected through the base line rotatable antenna array; rapidly identifying and outputting environment parameters by using the trained environment evaluation model, and evaluating the environment grade; constructing a dynamic direction-finding angle model by combining the attitude parameters and the motion parameters of the mobile platform, the control parameters of the antenna array and the environmental parameters; according to the environment parameters and the environment grades, a dynamic parameter optimization rule is formulated, and control parameters, direction-finding resolving parameters and signal processing algorithm parameters of the antenna array are adjusted; and based on the environmental parameters, the adjusted control parameters of the antenna array, the adjusted direction-finding resolving parameters and the adjusted adaptive filter parameters, calculating an incoming wave angle by using a dynamic direction-finding angle model. According to the method, high-precision incoming wave signal direction finding is realized in a dynamic environment, and the method is suitable for mobile scenes such as unmanned aerial vehicles and vehicle-mounted communication.

The invention belongs to the technical field of intelligent wireless sensing and radar signal processing, and particularly relates to a millimeter wave radar gesture recognition feature processing method, which is particularly suitable for scenes with environment interference (such as walking of others and static clutter), and specifically comprises the following steps: S1, preliminary filtering by a self-adaptive filter; s2, carrying out improved I CEEMDAN decomposition; s3, I MF component classification and processing; s4, signal reconstruction; the experimental result shows that the method provides a robust and efficient solution for gesture recognition, and can be widely applied to the fields of man-machine interaction, virtual reality, intelligent equipment control and the like.

The invention provides a full-parallel arbitrary multiplying power variable sampling system, and belongs to the technical field of signal processing. The system comprises an up-sampling system and a down-sampling system, the up-sampling system is used for a transmitter and comprises an up-sampling filter and an up-sampling interpolator, and the down-sampling system is used for a receiver and comprises a down-sampling filter, an extractor and a down-sampling interpolator; the up-sampling system can process four paths of input signals in parallel, and four paths of output signals are obtained after the four paths of input signals are processed in parallel; the down-sampling system is formed by cascading a plurality of down-sampling filters and an extractor, an extraction module is responsible for down-sampling of integer 2n times, and a decimal interpolator is connected behind the extractor to realize down-sampling processing of any decimal times. According to the invention, the limitation of traditional integer or simple fractional multiple sampling is broken through, arbitrary-multiplying-power precise resampling of the GHz-level signal is realized, the processing speed and the interpolation precision are obviously improved, the error is low, the anti-aliasing capability is strong, and the method is suitable for the high-requirement fields such as private network communication.

The invention discloses a gas signal detection device, a signal calibration synchronization method and a filter selection method, and the gas signal detection device comprises a sampling module which is used for collecting gas concentration; the signal calibration module is used for calibrating the gas concentration; and the signal processing module is used for filtering and synchronously processing the collected gas concentration to obtain the gas concentration meeting the detection requirement. According to the invention, the signal processing module is arranged to obtain the gas concentration after filtering and synchronous processing, when the gas concentration is subjected to data statistics, the concentration data meeting the response time requirement, namely the concentration data with shortened response time of the sampling module, can be effectively obtained, and the test precision is improved; meanwhile, through signal synchronous processing, time alignment of various output gas signals is achieved, effective data statistics is facilitated, and therefore the real heart and lung state of the tested person is obtained.

The invention discloses a distribution network power line anti-interference communication method based on adaptive filtering, and belongs to the technical field of distribution network power line communication. According to the method, a communication signal adopting a frequency shift keying modulation mode is acquired from a power line coupler of a distribution network through a signal acquisition module, the communication signal is preprocessed by using a digital signal processing unit, spectral analysis is performed on the preprocessed signal, and characteristic parameters of interference noise are extracted; a coefficient vector of a finite impulse response adaptive filter is initialized based on the characteristic parameters, the order of the filter is in direct proportion to the reciprocal of the dominant interference frequency, fine adjustment is carried out based on noise energy distribution through a table look-up method or a linear mapping relation, and the weight coefficient of the filter is adjusted in real time in the communication process. The adjustment step length is dynamically adjusted according to the real-time estimated signal-to-noise ratio, and finally, the processed signal is output through the adaptive filter and data demodulation is carried out. The method is mainly used for improving the anti-interference capability and the communication reliability of the power private line communication of the distribution network.

The invention relates to a preparation method of a surface acoustic wave filter integrated with a CMOS (Complementary Metal Oxide Semiconductor) process, which comprises the following steps of: preparing a CMOS radio-frequency signal processing circuit by using a silicon or silicon carbide substrate, combining a dielectric buffer layer with a piezoelectric material, and then depositing a metal interdigital structure on the surface of the piezoelectric material to prepare the surface acoustic wave filter. A passivation layer is deposited on the surface of the filter to protect the filter structure, finally a metal interconnection line and the passivation layer are prepared above the filter, and in order to not affect the performance of the filter, an air cavity is prepared between the passivation layer and the metal interconnection layer of the filter, so that the passivation layer and the metal interconnection layer are effectively isolated. According to the preparation method, the surface acoustic wave filter and the CMOS radio frequency circuit can be integrated, the problem that radio frequency front-end and rear-end signal processing cannot be integrated at the same time at present is solved, and the preparation method plays an important role in promoting development of a radio frequency chip in the directions of high integration, low cost, miniaturization and the like; and the radio frequency chip has wide practical value and economic value in the radio frequency chip application field.

The invention relates to the technical field of fuel gas ultrasonic metering, and discloses a self-adaptive filtering method based on ultrasonic metering and ultrasonic metering equipment, and the self-adaptive filtering method comprises the steps: delaying an uplink echo signal for preset time to generate an uplink echo reference signal, and delaying a downlink echo signal for preset time to generate a downlink echo reference signal; respectively inputting the uplink echo signal and the downlink echo signal into a self-adaptive filter for filtering, outputting an uplink echo output signal and a downlink echo output signal, and performing iterative adjustment on a weight coefficient of the self-adaptive filter by using a variable step size, the minimum mean square value of the uplink echo error signal and the minimum mean square value of the downlink echo error signal meet the preset requirements. The self-adaptive model based on correlation is used for echo signal processing during ultrasonic metering instantaneous time difference acquisition, and the problem that interference is within a frequency sweeping range is solved.

The invention discloses a multi-component insulating gas multispectral imaging device and an application method thereof, belongs to the technical field of electric power safety detection, and relates to a problem how to design a multifunctional, miniaturized and portable multi-component insulating gas multispectral imaging device. Through combination of the visible light camera and the infrared imaging lens, a visible light image of an electric power scene can be provided, infrared detection of insulating gas can be realized, and the application range of the device is expanded; the infrared characteristics of the multi-component insulating gas can be extracted through a plurality of broadband optical filters; infrared images of the multi-component insulating gas are collected, and high-precision gas detection and analysis are realized in combination with the data processing capability of the signal processing board; through the view field adjusting function of the infrared imaging lens, clear imaging results can be obtained at different distances and angles; the device has the advantages of multiple functions, high precision, high portability, high data processing efficiency and the like, is suitable for detecting and monitoring insulation gas leakage of power equipment, and has a wide application prospect.