821 results about "Peak detection" patented technology

The invention relates to the field of hard disk data protection, in particular to a hard disk data protection method and device based on artificial intelligence. The method comprises the following steps: acquiring a hard disk history monitoring log; performing multi-period hard disk load analysis on the historical hard disk monitoring log, and performing load peak fluctuation fitting so as to construct a hard disk load peak fluctuation curve; carrying out peak value trend evolution analysis on the hard disk load peak value fluctuation curve, and carrying out abnormal load peak value detection to obtain a time period where an abnormal peak value point is located; carrying out current time period redundant data calculation on the hard disk according to the time period of the abnormal peak point, and carrying out dynamic global data backup decision, so as to generate an abnormal peak global backup strategy; and performing abnormal write behavior detection and attack node tracing positioning on the hard disk historical monitoring log, and marking a hostile attack tracing positioning point. According to the invention, safe and reliable hard disk data protection is realized.

The invention relates to an ultrasonic flow metering device and a metering method thereof, and relates to the field of ultrasonic measuring devices. According to the metering device, through a cross-correlation operation circuit, a microcontroller, a double-threshold comparator, a peak detector, a gain adjustment circuit and a head wave threshold adjustment circuit, self-adaptive processing and adjustment of echo signals and head wave thresholds are achieved, and the accuracy and reliability of flow metering are improved. The metering method adopts an adaptive adjustment strategy of echo signal amplifier gain based on an output signal of an echo signal peak detection circuit, and a head wave threshold adaptive adjustment strategy based on a correlation operation value of echo signal sampling data and pre-stored reference wave data. According to the scheme, the stability of the echo signal and the rationality of the head wave threshold value are guaranteed, the method has adaptability to echo contour feature changes caused by transducer aging or contamination, and then the reliability of the flow metering process is guaranteed.

The invention relates to the technical field of power equipment state detection, in particular to an ultrahigh-frequency partial discharge online detection system, method and device and a medium, and the system comprises the steps: collecting an initial discharge signal in real time through an ultrahigh-frequency sensor array, and carrying out the preprocessing of the initial discharge signal, so as to obtain an ultrahigh-frequency discharge signal; carrying out peak detection on the ultrahigh-frequency discharge signal, and triggering a high-speed analog-to-digital converter to collect an original waveform when the amplitude exceeds a preset threshold value; performing multi-dimensional feature extraction on the original waveform by using a digital signal processor to obtain multiple groups of dimensional features; identifying and classifying the multiple groups of dimension features based on a random forest algorithm, generating discharge type labels and confidence coefficients, and storing the discharge type labels and the confidence coefficients in a dynamic database; carrying out spatial position calculation on the ultrahigh-frequency discharge signal by adopting a time difference method, and determining a three-dimensional coordinate of a discharge source; the dynamic database and the three-dimensional coordinates of the discharge source are subjected to space-time correlation and multi-dimensional analysis, a defect analysis result is generated, and high-precision online detection of the partial discharge defect of the high-voltage equipment is achieved.

System and method for determining valid heartbeats includes an external device and implantable pressure sensor (IPS) that senses pressure for a period of time and generates a pressure signal. The pressure signal is segmented into pseudo-systolic and pseudo-diastolic segments, and it is determined whether the pressure signal starts with one of the pseudo-systolic or pseudo-diastolic segments. In response to the pressure signal starting with a pseudo-diastolic segment, systolic content of at least one of the pseudo-systolic segments is modified based on diastolic content of at least one of the pseudo-diastolic segments. In response to the pressure signal starting with one of the pseudo-systolic segments, the systolic content of at least one of the pseudo-systolic segments is modified based on the systolic content of at least one of the pseudo-systolic segments, and valid heartbeats are determined based on the modified systolic content.

The invention relates to the technical field of fire control, in particular to an electrical fire control method and system based on multiple sensors, and the method comprises the steps: obtaining related data of electrical fire influence factors, and carrying out the preprocessing; extracting a current peak value by using an AMPD peak value detection algorithm according to the preprocessed current data, and constructing an arc fault strength index; combining the arc fault strength index and temperature data, analyzing the relationship between arc fault abnormal heat release and temperature change, constructing an electrical heat dissipation goodness, integrating the electrical heat dissipation goodness and the change rule of carbon monoxide and carbon dioxide concentration, constructing a fire risk index, and quantifying the risk degree of electrical fire occurrence; and correcting the SOS anomaly detection algorithm based on the fire risk index to obtain a corrected significant anomaly score, and preventing and controlling the electrical fire according to the significant anomaly score. According to the invention, the fire risk index is constructed in combination with various sensor data, and the electrical fire early warning accuracy and prevention and control efficiency are improved.

The invention relates to the technical field of valve leakage detection, and particularly discloses an ultrahigh pressure gas valve leakage detection method and system. According to the method, a unified leakage feature vector is obtained through multi-source acquisition and processing; capturing a time sequence dependency relationship, and determining a micro leakage mode; carrying out abnormal peak detection to obtain a preliminary leakage probability; combining the initial leakage probability with real-time environmental parameters, and dynamically adjusting a judgment standard; comparing the unified leakage feature vectors through a judgment standard, fusing position coordinate triangulation positioning, judging whether micro crack leakage occurs or not, and obtaining leakage position estimation; the historical data sequence is fused, the micro crack development trend is predicted, and the early warning level is determined; and generating a corresponding response signal according to the early warning level, and outputting micro crack leakage early warning. Multi-source data fusion, dynamic threshold adjustment and position prediction can be carried out, the accuracy and robustness of micro crack leakage detection are remarkably improved, and efficient guarantee is provided for safe operation of a pipeline.

The invention relates to the technical field of digital control switching power supplies, and particularly discloses a switching power supply dynamic response adjusting system based on digital control, which comprises a digital controller, a multi-channel analog-to-digital conversion module, a parameter identification module, a self-adaptive control law adjusting module, a pulse width modulation driving module and a stability monitoring module. On-line identification of key parameters of a system is realized by constructing a nonlinear state space model and combining an extended Kalman filtering algorithm, dynamic compensation is carried out for non-minimum phase characteristics such as a right half plane zero point, and a self-adaptive control law adjustment module optimizes a control strategy in real time according to an updated model. A Lyapunov stability criterion and a predictive control mechanism are introduced, the robustness and response speed of the system are improved, and a stability monitoring module identifies an abnormal state through sliding window variance analysis and peak detection and triggers a fault-tolerant mechanism to guarantee safe operation of the system.

The invention relates to the technical field of high-precision anti-interference satellite navigation, and particularly discloses a detection and suppression method for suppressing deception combination interference of high-precision anti-interference navigation. One or at least two of space-frequency joint-multi-beam / zeroing-noise subspace projection, correlation peak detection and screening, true convex false deception jamming suppression detection, deception jamming recovery and cancellation, improved PAC and dense suppression / isolated suppression deception / dense suppression deception jamming subspace rapid solving methods are adopted for deep fusion; detection and suppression of combined interference are realized. According to the method, the problems of detection and suppression of combined interference of isolated suppression and weak cheating, dense suppression and weak cheating, isolated suppression and stronger cheating, dense suppression and stronger cheating, isolated suppression and strong cheating, dense suppression and strong cheating and the like are solved.

The invention belongs to the technical field of marine surveying and mapping, and discloses an airborne marine laser radar underwater weak echo signal detection method and system. According to the method, a waveform rising edge is determined by constructing a standard deviation curve, a water surface echo moment is accurately extracted, and two water surface geometric elements of a water surface point and a refraction vector are calculated on the basis; constructing a time-space constrained waveform superposition model, taking the Euclidean distance between the two water surface geometric elements as a neighbor discrimination standard, and screening and superposing neighbor waveforms by using a K neighbor judgment method to obtain a superposed pseudo waveform with a high signal-to-noise ratio; and finally, an improved normalized saliency peak detection method is utilized to judge the underwater echo position step by step and obtain the final underwater echo moment. After the model constructed by the invention is used for processing, the underwater weak echo detection of the airborne ocean laser radar is effectively realized, the maximum sounding performance of the airborne ocean laser radar is improved, and an effective technical support and a solution are provided for sounding data processing and application.

The invention discloses an ion chromatography wave crest boundary extraction method based on fitting residual and tangent judgment, and belongs to the technical field of ion chromatography analysis. Comprising the following steps: S1, reading an original waveform data sequence, and executing frequency reduction sampling according to a set step length; s2, calculating the slope of the data after underclocking sampling by using a difference method, and searching positive and negative slope sections by performing first-order derivation on the waveform after underclocking sampling; s3, noise interference is eliminated, slope areas are grouped, then a chromatographic peak detection limit value is set, and an effective peak left section and an effective peak right section are screened out; s4, combining the effective wave crest left side section and the effective wave crest right side section to obtain an effective wave crest and a preliminary left boundary point and a preliminary right boundary point of the effective wave crest; s5, fitting a straight line through the preliminary left boundary point and the preliminary right boundary point to position an error integral region; and S6, updating the optimal boundary point by traversing the evaluation indexes of all points in the error integral region. The boundary search range is more accurate, and the calculation efficiency is higher.

There is described an artificial intelligence wearable ECG skin patch (400) to detect sudden cardiac arrest. The wearable ECG monitoring patch (400) with AI based predictive analytics and remote based cardiac monitoring (615) system that can detect cardiac arrhythmias automatically in real-time and make a diagnosis with AI models trained with acquired data. The wearable skin has a biocompatible polymer patch (400) which captures the electrical signal through a flexible printed electronic technology based conducting ink and a substrate. The microcontroller controls (201), store and transmit the data packets. The IoT connected signal transmission is capable of recording and transferring the data packets through wireless communication. The AI engine is capable of analysing, evaluating, testing and providing the data packets of sudden cardiac arrest through a peak detector algorithm. The ECG skin patch (400) to detect and measure the sudden cardiac arrest with the R-R interval time series to obtain heart rate variability.

The invention discloses a random access preamble and detection algorithm design based on low earth orbit satellite communication. Specifically, firstly, a novel lead code with a plurality of subsequences is provided, in order to enlarge the number of available lead codes in a wave beam, a ZCM sequence is introduced to form the subsequences, and orthogonal frequency division multiplexing is adopted for modulation and is sent to a channel. Subsequently, a timing advance (TA) detection algorithm is proposed. The first sub-sequence is used for decimal time delay detection, and the other sub-sequences are used for integer time delay detection. In addition, the peak detection ingeniously utilizes the variance of the power delay spectrum, so that the detection performance is improved. Finally, a simulation result shows that the lead code provided by the invention is almost not influenced by frequency offset, does not need pre-compensation, and is suitable for being applied to low-orbit satellite communication with relatively large frequency offset.

The invention belongs to the technical field of data processing, and particularly relates to a multi-dimensional holographic data analysis method and system for hazardous waste supervision, and the method comprises the steps: obtaining fluorescence spectrum data and mass spectrum data; preprocessing the acquired data, and carrying out peak detection by utilizing a first-order derivative of peak intensity based on a preprocessed fluorescence intensity matrix; determining the weight of each peak point in combination with the fluorescence spectrum of the standard sample to complete the matching of peak pairs, and calculating the peak matching distance and the distribution difference of the feature vectors; calculating a similarity score of the spectrum by integrating the peak matching distance and the distribution difference of the feature vectors and combining a matching ratio and a weight ratio; calculating weighted cosine similarity and Euclidean distance between the processed mass spectrum data and the mass spectrum data of the standard sample, and completing calculation of the similarity score of the mass spectrum between the samples; and tracing the source of the hazardous wastes according to the similarity score of the spectrum and the similarity score of the mass spectrum. And accurate traceability is realized through qualitative and quantitative analysis.

The invention discloses a non-contact drunk driving detection method and system adopting a large-linewidth tunable laser, and relates to the technical field of laser detection, and the method comprises the steps: collecting transmission light signals and corresponding electric signals under different linewidth conditions through experiments, synchronously recording experiment parameters, obtaining an original data set, carrying out the preprocessing of the original data set, and carrying out the detection of drunk driving. Generating a training set, a verification set and a test set, and training a BP (Back Propagation) neural network to obtain a pre-trained noise suppression model; the method comprises the following steps of: generating a wavelength-tunable modulated laser beam by adopting a large-linewidth tunable laser, directionally projecting the modulated laser beam into a vehicle cab, and enabling laser to penetrate through the cab space and carry alcohol gas concentration information to obtain a transmission light signal; focusing the transmission light signal to a photoelectric detector through an optical convergence device to obtain a noisy electric signal, inputting the noisy electric signal into a pre-trained noise suppression model, and outputting a de-noised electric signal; performing synchronous demodulation and harmonic analysis on the de-noised electric signal by using a phase-locked amplification detection technology, extracting a second harmonic signal amplitude associated with the modulation frequency, and determining a second harmonic signal characteristic amplitude through peak detection; according to the calibration relation between the second harmonic signal characteristic amplitude and the alcohol gas concentration, the concentration value of the alcohol gas in the cab is calculated in an inversion mode through a least square fitting algorithm, an alcohol concentration threshold value is set, the drunk driving condition of a driver is judged, a detection result is generated, and an alarm signal is output.

The invention relates to the technical field of medical data processing, and provides a medical image data processing method based on deep learning, which comprises the following steps of: acquiring data according to an acquisition template, extracting a pulse time sequence by self-adaptive threshold peak detection, calculating an instantaneous phase according to linear interpolation, calculating a statistical magnitude, comparing a quantitative index with a preset threshold value, and calculating a pulse time sequence according to the statistical magnitude. Judging a steady state by combining a peak loss rate and an abrupt change detection rule, and calculating phase consistency between channels for verification; the method comprises the following steps of: splitting acquired data according to a concept entity to form a data relation model, implementing rapid global rigid estimation and applying affine transformation, estimating a pixel-level displacement field by adopting a pyramid dense optical flow network, applying the displacement field to an original pixel, and performing time domain fusion by taking optical flow confidence and a registration residual error as weights; and cutting the short-time image stabilization sequence after registration compensation, and outputting a pixel-level risk thermodynamic diagram, a candidate focus list and each output confidence interval by taking a hybrid network of a convolution front end and a space-time Transform backbone as a prediction model.

The invention discloses a channel-configurable liquid particle pulse amplitude detection method and a related device, and relates to the field of digital signal processing, and the method comprises the following steps: eliminating a background noise reference value of a digital pulse signal, presetting a dynamic threshold value, filtering a noise signal of which the amplitude value is lower than the dynamic threshold value in the digital pulse signal, and obtaining a channel-configurable liquid particle pulse amplitude detection result; obtaining a baseline correction digital pulse signal; when the amplitude of the baseline correction digital pulse signal exceeds a dynamic threshold for the first time, pulse counting is started, peak detection is carried out on the baseline correction digital pulse signal, and a pulse peak value and a peak value position corresponding to a pulse event are obtained; a channel threshold parameter is preset through an upper computer, a plurality of independent channels are divided, pulse events are loaded into the corresponding independent channels to be accumulated, a channel count value and corresponding particle size distribution data are obtained, and liquid particle pulse amplitude detection is completed. The problem that the number of channels and threshold parameters cannot be dynamically adjusted when a current hardware circuit is used for liquid particle pulse amplitude detection is solved.

The invention discloses a chip interface safety protection control circuit, which relates to the technical field of chip interface protection, and comprises a power supply control module which is used for carrying out rectification filtering and voltage stabilization processing on accessed electric energy, meeting power supply requirements, carrying out overcurrent detection, constant current regulation and overcurrent power-off protection control, and carrying out power-off protection on the power supply control module during power-off protection. The interface voltage of the chip module is lowered, the interface sampling module can carry out sampling and peak detection on pulse signals accessed or output by the chip module, the state detection module can judge the type of the pulse signals, namely square wave pulses or sine pulses, and the first sampling module and the second sampling module carry out peak sampling according to the type of the pulse signals. The micro-control module controls the threshold value setting module to set a comparison threshold value, then the abnormity detection module detects the peak value state of the pulse signal, and when the peak value state is larger than the normal peak value state, chip interface protection is carried out. The chip interface safety protection control circuit can automatically carry out interface signal detection and interface protection control.

The invention discloses a voice interactive chart dynamic generation method and system based on a large language model, and relates to the technical field of chart generation, and the method comprises the steps: collecting a user voice signal, carrying out the preliminary framing, calculating the short-time energy, and analyzing a mute segment set signal; frequency domain signals are extracted from the set signals, gain is calculated through a filter, noise reduction is carried out on the frequency domain signals, the zero-crossing rate and noise reduction short-time energy are calculated, effective voice frames are screened, peak detection is carried out, the average voice speed is calculated, voice speed normalization is carried out, and signal values of sampling points in the frames are extracted. According to the method, the noise power spectrum density is extracted through FFT on the mute section, a frequency domain model of background noise is effectively established, a follow-up filter can accurately act on an actually existing frequency band interference area, weakening of the voice main signal spectrum is avoided, the Mel filter bank is accessed after the power spectrum is calculated through the FFT after frame windowing, and the noise power spectrum density is calculated through the FFT after frame windowing. Energy can be redistributed on the logarithmic Mel scale according to human ear perception characteristics.

The invention discloses a digital gain adjustment control circuit which comprises a power detector, a digital peak detector, a gain control module and a digital gain adjustment module. The power detector calculates the power of an input signal by adopting a smooth root-mean-square algorithm, and rapidly adjusts a gain coefficient according to different step lengths adapted to regions; the digital peak value detector adopts a sliding window maximum value method to detect the peak value of an input signal, carries out statistical counting on the overload and underload states of the peak value based on a two-stage method, and judges and adjusts the gain according to a comparison result with a threshold value, so that the influence of frequent gain refreshing on the AGC loop state is avoided, and the loop stabilization time is shortened. Flexible algorithm upgrading and parameter configuration are supported by adopting a full-digital framework, different communication standards are adapted through firmware updating, the limitation of single index control is solved through a dual-detection cooperative working mode, peak overshoot is effectively restrained while the average power of the system is kept stable, the system is conveniently integrated to an SoC chip through modular design, and the reliability of the system is improved. And the power consumption and the size are greatly reduced.

The invention discloses an LC-MS peak detection method, device, equipment and medium, and the method comprises the steps: firstly obtaining an original data set of an environment sample collected by an LC-MS instrument, extracting and adjusting peak detection parameters, and determining a plurality of peak regions and characteristic parameters thereof; generating a synthetic peak region and synthetic characteristic parameters which are consistent with the real peak region in characteristic parameter distribution by using a conditional generative adversarial network, and then constructing an LC-MS peak detection model comprising a peak region classification model and a peak boundary defining model through a lightweight multi-task convolutional neural network based on the characteristic parameters and the synthetic characteristic parameters; and finally, inputting to-be-detected sample data into the model to obtain a detection result. According to the method, peak detection parameters are directly extracted from original data and dynamically adjusted, classification of peak regions and peak boundary integration are synchronously completed in combination with the improved lightweight multi-task convolutional network, the real-time detection requirement is met, and finally high-precision detection of real positive peaks is achieved and the noise amount is remarkably reduced.

The invention provides a digital receiver circuit and a control method thereof. The digital receiver circuit comprises a frame synchronization detection module, a symbol synchronization detection module and a symbol decoding module, the frame synchronization detection module comprises a first matched filter and a first peak detection module; the first matched filter is used for performing convolution operation on a guide code sequence in the received synchronization signal to obtain a convolution operation result; the first peak value detection module is used for determining the position of a convolution peak value according to the convolution operation result; determining the end position of the guide code sequence according to the position of the convolution peak value; the symbol synchronization detection module is used for detecting positioning information of an end position of each symbol in effective data connected with the guide code sequence; according to the positioning information, determining a pulse sequence corresponding to a judgment moment of symbol decoding of the effective data; and the symbol decoding module is used for performing symbol decoding on the effective data according to the judgment time and the pulse sequence. The technology can improve the accuracy of signal detection and decoding.

The invention discloses a chromatographic data optimization processing method for a liquid chromatograph, and relates to the technical field, and the method comprises the following steps: collecting an original signal flow, carrying out preliminary peak detection, and generating an original peak list; extracting modal exclusive characteristics of each chromatographic peak; converting the modal exclusive features into a unified multi-dimensional semantic feature vector; calculating a time interval weight, and calculating a semantic relevancy weight based on the multi-dimensional semantic feature vector; correcting the time interval weight, generating a network edge weight, and constructing a peak correlation topology network by taking the multi-dimensional semantic feature vector as a node; identifying node clusters connected with high edge weights, and aggregating the node clusters into candidate compound entities; tracking a node signal intensity change track, and adding a conflict mark; conflict resolution arbitration is carried out on the candidate compound entities with the added conflict marks, dominant detector evidence is output, and an analysis report is generated. According to the method, the problems of poor data collaboration of multiple detectors, inaccurate peak identification and association and isolated data processing flow are effectively solved.

The invention provides a permanent magnet synchronous linear motor, a control system and a position resolving method thereof, and relates to the technical field of motor control. The method comprises the following steps of: firstly, equidistantly arranging at least two pairs of linear Hall sensors with an electrical angle difference of 90 degrees and overlapped detection intervals along a stator, and acquiring orthogonal voltage to calculate an instantaneous position angle; the sensor pairs are dynamically switched through peak judgment and spliced to obtain the full-stroke continuous absolute position, and the instant speed is obtained through difference; the position and the speed are respectively input into a position loop, a speed loop and a current loop, and vector closed-loop control is realized by driving an inverter through SVPWM, so that high-resolution position and speed feedback is provided in the whole stroke, and the dynamic response and positioning precision of the linear motor are remarkably improved.

The invention belongs to the field of high-precision time calibration and navigation positioning, and discloses a rubidium atomic clock calibration method based on a Rowland system and a related device. Spectral analysis is performed based on a Welch method and an adaptive peak detection method so as to accurately identify frequency, amplitude and phase parameters of periodic components, then a mixed time difference model including a secondary trend term, a multi-period term and a noise term is constructed, and the model is solved by adopting a least square method so as to obtain key performance parameters of the rubidium atomic clock. And finally completing time calibration of the Rowland system taming rubidium clock. By adopting the method, the parameter estimation precision of the rubidium clock is effectively improved, the problems of mode aliasing, noise sensitivity, non-unique result, low calculation efficiency and the like are solved, and reliable and real-time calibration of the rubidium atomic clock by the Roland system is realized.

The invention belongs to the technical field of detection, and particularly relates to a capacitance detection system for a pipetting steel needle and a capacitance signal processing method. The system comprises a pipetting needle, a capacitance voltage division circuit, a frequency selection circuit, a peak detection circuit and a subtraction amplification circuit which are connected in sequence. The capacitance voltage division circuit is connected with a signal generation circuit; the subtraction amplification circuit comprises a processing unit circuit, the processing unit circuit comprises a signal processor, and the signal processor is an MCU unit with an ADC-1, an ADC-2 and a DAC; the peak detection circuit outputs an S0 signal, and the S0 signal is accessed to ADC-1 of the processing unit circuit; a bias voltage VBias is subtracted from the S0 signal output by the peak detection circuit at the same time to obtain a V1 signal, and the bias voltage VBias is given by a DAC (Digital-to-Analog Converter); and the V1 signal from which the VBias is subtracted is further amplified. The method is high in detection response speed and can be applied to high-speed instruments.

The invention discloses a pulling and lifting cable frequency detection and cable force measurement method and system based on a millimeter wave radar, and belongs to the field of pulling and lifting cable force measurement. The method comprises the steps that vibration signals are collected through the millimeter wave radar to obtain complex data streams, time-frequency analysis is conducted on the complex data streams, and an interference model is established; the method comprises the following steps: reconstructing a noise-reduced vibration signal by adopting adaptive filtering, extracting candidate vibration frequencies through power spectral density estimation and spectral peak detection, calculating corresponding stability scores, and obtaining a first verification factor used for evaluating wind disturbance and a second verification factor used for evaluating vibration frequency deviation; according to the method, through multi-source sensing data fusion and self-adaptive signal processing, complex environment interference is effectively overcome, non-contact high-precision cable force measurement is achieved, and the method has the outstanding advantages of being high in anti-interference capacity, high in measurement reliability and the like.

The invention relates to a health index monitoring tooth socket and a monitoring method thereof, and the method comprises the steps: collecting an optical signal in an oral cavity in real time through a collection module, and extracting a DC component and an AC component from the optical signal; and evaluating the signal quality of the direct-current component and the alternating-current component according to the standard signal proportion, and obtaining a target direct-current component and a target alternating-current component which meet the standard signal quality. On the basis of the cross correlation between the target direct-current component and the target alternating-current component, the blood oxygen saturation health index is obtained through a piecewise function. Based on the target alternating component, the heart rate health index is obtained through peak value detection. The problem of low monitoring accuracy of a monitoring method for monitoring health indexes in related technologies is solved.

The invention discloses an FPGA-based sound wave multiple reflection sediment concentration measurement method. The method comprises the following steps: constructing an ultrasonic underwater measurement system capable of realizing ultrasonic multiple reflection and driving the ultrasonic underwater measurement system to work; an ultrasonic transducer is driven by the FPGA to emit ultrasonic waves; echo signals of the ultrasonic waves passing through the turbid liquid are collected, subjected to analog-to-digital conversion and then transmitted to the FPGA; digital filtering and peak detection are carried out on the echo data based on the FPGA; according to a peak value detection result, an ultrasonic attenuation coefficient is calculated based on the FPGA in combination with numerical integration; for a plurality of turbid liquid bodies of the same type with known sediment concentrations, the second step to the fifth step are executed respectively, ultrasonic attenuation coefficients under different concentrations are obtained, and then fitting is conducted on the ultrasonic attenuation coefficients and the concentrations to obtain a regression equation of the attenuation coefficients and the sediment concentrations; and executing the second step to the sixth step to obtain an ultrasonic attenuation coefficient aiming at a to-be-detected turbid liquid body, and substituting the ultrasonic attenuation coefficient into the regression equation to obtain the sediment concentration of the to-be-detected turbid liquid body. According to the method, the defects of the traditional method in real-time performance and precision are overcome, and the real-time performance and accuracy of sediment concentration measurement are remarkably improved.

The utility model relates to the technical field of satellite navigation, in particular to a satellite navigation anti-interference signal intensifier, which comprises a receiving antenna, a prefilter, a fixed amplification module and an automatic gain module which are sequentially connected, the output end of the fixed amplification module is further connected with a control module, and the control module comprises a peak value detection unit and a switch control unit. Two output ends of the switch control unit are connected with a control end of the automatic gain module, the peak detection unit is used for detecting a signal peak value, and the switch control unit controls the amplification factor of the automatic gain module based on the signal peak value output by the peak detection unit. According to the utility model, the prefilter is used for filtering interference signals, then the peak value detection unit is used for judging the magnitude of the signals, and then the switch control unit is used for selecting different resistors, so that the amplification factor of the automatic gain module is changed, the signals are enhanced, the final signals are in a proper range, subsequent signal processing is facilitated, and the practicability is higher.

The present invention relates to a single photon avalanche diodes-based time-of-flight sensor (100). The single photon avalanche diodes (SPADs) based time-of-flight (ToF) sensor (100) includes an Nx N single photon avalanche diode (SPAD) photodetector (101), a front-end (FE) unit (103), a pulse shaping (PS) unit (105), a pulse store unit (107), a peak detection unit (109), a digital logic unit (111), a timing processing circuitry unit (113), and memory elements unit (115). Due to integration of multiple units in single photon avalanche diodes (SPADs) based time-of-flight (ToF) sensor (100), the single photon avalanche diodes-based time-of-flight (ToF) sensor (100) accurately measures distance by adequate, suitable, and efficient elimination of background light.