100 results about "Matched filter" patented technology

The invention relates to an optical cable monitoring and data analysis method and device, equipment and a medium. The method comprises the following steps: acquiring current state data of an optical fiber link, and dynamically generating adaptive pulse coding parameters and matched filter parameters based on the data by using a deep reinforcement learning agent, so as to generate and inject coded pulses into the optical fiber link; and then receiving an echo signal, performing matched filtering processing on the signal by using the generated matched filter parameter to obtain a filtering output signal, further calculating a performance index vector and a reward signal, and finally updating a strategy network of the intelligent agent by using the reward signal, thereby realizing continuous optimization of pulse coding and matched filtering parameters. Therefore, the system can automatically adapt to the dynamic change of an optical fiber link, the spatial resolution, the dynamic range and the signal-to-noise ratio are effectively improved, and the adaptive capability and the robustness of the system are enhanced at the same time.

The invention discloses a foundation pit support deformation real-time monitoring method based on edge calculation, and aims to solve the problems of multi-node time synchronization and clock drift compensation caused by unavailability or poor quality of satellite navigation and precise time protocols in an underground or shielded environment. According to the method, through event dictionary learning, partition time slot scheduling and safety coding micro excitation time synchronization, matched filtering decoding, multi-scale arrival time estimation, paired time difference robust fusion, frequency priority and phase speed limit correction and network disconnection time holding, the time synchronization efficiency is improved; the technical effects that multi-source data alignment, deformation field reconstruction and graded early warning are completed on the unified virtual reference time scale, and high-precision synchronization and online drift compensation are obtained without depending on the external time service condition are achieved.

The invention provides a carbon monoxide plume identification and quantification method based on a domestic hyperspectral satellite, and the method comprises the steps: carrying out the radiometric calibration and atmospheric correction of the data of a visible short-wave infrared hyperspectral camera AHS I carried by the domestic hyperspectral observation satellite (GF-5B, Gaofen-5 B satellite); generating a carbon monoxide unit absorption spectrum by using a medium-resolution atmospheric transmission model MODTRAN; inverting a carbon monoxide enhancement value by adopting a matched filtering method; generating a binary plume mask through threshold segmentation; and constructing a deep learning model based on a residual neural network ResNet network, and realizing plume pixel-level identification and carbon monoxide column concentration enhancement value prediction. The method can identify the carbon monoxide plume with high precision and high efficiency, and is suitable for atmospheric pollution monitoring and pollution source quantification.

The invention discloses a front-feedback combined burst signal fast symbol synchronization method, which relates to the technical field of digital signal processing and satellite communication, and comprises the following steps: firstly, sampling a received signal subjected to matched filtering processing according to a 4-time symbol rate by using an initial NCO (Network Controlled Oscillator), then dividing a sampling value into two paths, sending one path to an FIFO (First In First Out) register for caching, and using Oamp in the other path; the method comprises the following steps of: firstly, performing timing deviation estimation by using an FIFO (First In First Out) register and an M algorithm, secondly, determining a moment when the FIFO register starts to read data, an oscillation initial value of an interpolation control NCO and an initial value of an interpolation coefficient according to a timing deviation estimation result, starting the interpolation control NCO, and then, sending the data read by the FIFO register into a Farrow structure interpolation filter for interpolation processing according to the initial value of the interpolation coefficient. And finally, a Gardner loop is started, feedback control is carried out on the interpolation control NCO, and an interpolation result is output, so that the fast symbol synchronization speed and precision of the burst signal are improved, and the stability and timeliness of fast symbol synchronization of the burst signal are guaranteed.

The invention relates to a computer-implemented method for determining spatially resolved radiation load information of a patient when conducting an examination with an imaging X-ray apparatus having an X-ray radiator for outputting an X-ray field for conducting the examination, wherein patient input dose information is determined for determining the radiation load information, wherein the pre-dose information is determined in the case of use of a matching filter arranged between the patient and the X-ray radiator, which causes a non-uniform dose distribution in a plane perpendicular to a central ray of the X-ray field, the pre-dose information describing a uniform distribution of the X-ray dose acting on the patient without the matching filter; dose distribution information is calculated using the pre-dose information by means of a filter model, which describes at least the dose distribution of the X-ray dose acting on the patient in the part of the X-ray field covered by the matching filter; and the patient input dose information is determined using the dose distribution information.

This invention discloses a network synchronization device that may include a matched filter. The matched filter may be configured to generate an event for synchronizing the operation of elements in the network, at least in part in response to a timing frame generated at a network switch. The event for synchronizing the operation of the element may include a first event generated at least in part in response to first information associated with a first element and a second event generated at least in part in response to second information associated with a second element. Related systems and methods are also disclosed.

A system and methods are disclosed. The method includes obtaining a seismic dataset including a plurality of recorded multiple events, generating a predicted multiple model using a multiple prediction method and the seismic dataset, and estimating a set of initial matching filters using a matching method, to match the plurality of estimated and recorded multiple events. The method further includes generating a tensor field based on the predicted multiple model, determining a set of structure-oriented matching filters based on the set of initial matching filters and the tensor field, generating a filtered multiple model based on the predicted multiple model and the set of structure-oriented matching filters, and generating a multiple-attenuated seismic dataset based on the filtered multiple model and the seismic dataset, forming a seismic image based, at least in part, on the multiple-attenuated seismic dataset, and determining a location of a hydrocarbon reservoir based on the seismic image.

The application provides a satellite navigation deception jamming identification and positioning method based on passive synthetic aperture, comprising the following steps: mounting an antenna and a deception jamming signal receiver on a moving carrier and designing the moving carrier to move at a constant speed above a deception jamming source; designing the antenna to continuously receive deception jamming signals emitted by the deception jamming source below in a horizontal beam coverage time; processing the deception jamming signals by the receiver to obtain Doppler signals; performing matched filtering of the Doppler signals r'' under different matched filter frequency conditions by using a matched filter to obtain a frequency modulation-frequency modulation-time two-dimensional search matrix; obtaining the frequency modulation of the signal r'' based on the frequency modulation-frequency modulation-time two-dimensional search matrix; calculating the radial distance between the receiver and the deception jamming signal source under the zero Doppler plane based on the frequency modulation of r''; calculating the position information of the deception jamming source based on the radial distance; and judging the deception jamming signal according to the position information of the deception jamming source.

The invention provides an extended target phase offset coherent waveform design and efficient accumulation method. The method comprises the following steps: acquiring a pulse signal of a JFPA waveform received by a target, returning echo signals of a plurality of extended targets, and searching a target coarse velocity by using a minimum envelope entropy, constructing a matching function to perform motion compensation on the echo signal to obtain a two-dimensional time domain signal; taking the jitter initial phase of the echo signal corresponding to the reference waveform as a matched filter, and compensating the jitter initial phase of the echo signal corresponding to the coherent accumulation waveform; and designing the echo signal after initial compensation as a coherent echo signal, and performing Fourier transform on the coherent echo signal along slow time to obtain a coherent accumulation result of the target. According to the method, accurate initial phase jitter compensation is completed without target distance information, the method is suitable for an extended target, and after the echo signal of the JFPA waveform is subjected to initial phase jitter compensation, the phase is controlled to be uniform, so that the complexity of FFT coherent processing can be reduced.

The application provides a single-station moving ship active and passive cooperative positioning method based on relaxation transformation. The method comprises the following steps: a single-station synthetic aperture radar receives a plurality of frames of radiation pulse signals from a ship, obtains a pulse repetition interval sum, a time difference of arrival measurement value and a Doppler phase measurement value of the ship, and further determines a passive measurement matrix of the ship; based on the pulse repetition interval sum and the speed and position of the ship, a theoretical measurement matrix of the ship is determined to construct a ship positioning model, a weighted least square method and a semi-positive definite relaxation transformation algorithm are used for solving, and a predicted position and a predicted speed of the ship are obtained; a radar wave is emitted to the predicted position of the ship to obtain a scene echo of the ship; a matched filter is designed to coarsely focus the scene echo and extract a peak value signal, the peak value signal is inversely focused and inverted, and a ship echo signal is obtained; the ship is imaged by using the echo signal, and an actual position of the ship is determined according to an imaging result.

An antenna calibration system and method use a transmitter antenna array and a receiver antenna array. Calibration automatically initiates in response to a trigger condition. Each receiver antenna in the receiver antenna array receives frequency-modulated signals from the transmitter antenna array. Optionally, the transmitter antenna array transmits signals of increasing frequency ("up chirps") and / or signals of decreasing frequency ("down chirps"). The frequency-modulated signals are processed through matched filters to determine filter responses. The phase differences for each receiver antenna are calculated based on the filter responses. Calibration coefficients for each receiver antenna are generated based on the calculated phase differences. The phase of signals received from the receiver antennae are then adjusted using the respective calibration coefficients.

The invention relates to a phase noise compensation method and a distributed optical fiber sound wave sensing system. The method comprises the following steps: S1, simultaneously receiving a light source phase noise signal and a coherent receiving signal of a scattering signal for sensing through a group of coherent receivers; s2, performing low-pass and high-pass filtering on the coherent receiving signal, and extracting a light source phase noise reference signal and a sensing signal; s3, on the basis of the phase noise reference signal, respectively performing phase noise extraction and reconstruction on the transmitted detection optical signal and the local oscillation optical signal in the coherent receiving process; s4, compensating phase noise introduced by local oscillation light according to the reconstructed phase noise signal, and performing time domain and frequency domain reconstruction on the detection light signal to obtain a matched filtering kernel function after phase noise compensation; and S5, carrying out signal demodulation based on the coherent receiving signal after phase noise compensation and the reconstructed matched filtering kernel function. Compared with the prior art, high-precision phase noise compensation can be realized under the condition of low complexity.

The application discloses a SAR polar coordinate imaging method and device based on flat flight equivalence, and the method comprises the following steps: constructing a flat flight equivalence slant range model of a large oblique SAR to obtain a baseband echo signal formed by target area scattering; performing distance direction matched filter processing on the baseband echo signal to obtain a signal after range pulse compression; sequentially performing Dechirp processing, two-dimensional resampling processing and IFFT transformation on the signal after range pulse compression to obtain a SAR polar coordinate primary imaging result; and performing geometric correction on the primary imaging result based on reverse projection to obtain an imaging result without geometric deformation and with good focusing. The SAR polar coordinate imaging method based on flat flight equivalence provided by the embodiment avoids the problem of azimuth translation invariance caused by diving through slant conversion, solves the problem that the traditional PFA is not applicable to diving SAR, and successfully extends the PFA imaging algorithm without deformation to diving SAR by correcting the geometric deformation problem caused by diving.

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

This invention discloses a method for non-integer multiple sampling rate transformation based on a digital matched filter. The method includes the following steps: calculating the phase adjustment value related to the non-integer multiple sampling rate transformation based on the input-output sampling frequency relationship; determining the phase adjustment accuracy based on the input-output sampling frequency relationship; designing a digital filter based on the phase adjustment accuracy to obtain the digital matched filter impulse response value; and using the phase adjustment value as an index of the digital matched filter impulse response value to perform matched filtering calculations, thereby realizing the non-integer multiple sampling rate transformation. This invention significantly reduces the complexity of digital filter design, saves development time and costs, and offers high flexibility and effectiveness for systems requiring fractional multiple transformation and matched filters in communication systems.

The invention provides a multi-order sideband-based multi-resolution distributed optical fiber acoustic wave sensing method, which comprises the following steps of: generating a detection light pulse comprising a plurality of linear frequency modulation sidebands with different sweep bandwidths, and injecting the detection light pulse into a sensing optical fiber; receiving a Rayleigh backscattering signal generated in the sensing optical fiber to obtain an electric signal containing vibration information distributed along the sensing optical fiber; matching filter banks corresponding to a plurality of linear frequency modulation sidebands with different frequency sweeping bandwidths are adopted, parallel matching filtering processing is carried out on the electric signals, a plurality of distributed sound wave sensing signals with different spatial resolutions are decoupled from the electric signals, and the spatial resolutions are determined by the frequency sweeping bandwidths corresponding to the linear frequency modulation sidebands; based on a plurality of distributed sound wave sensing signals with different spatial resolutions, multi-resolution sound wave vibration monitoring along a sensing optical fiber is realized.

The invention discloses an electrosurgical tissue impedance measurement system and method based on frequency domain analysis. The system comprises a main energy generation module, a modulation signal generation module, an output superposition module, a signal acquisition module, an impedance calculation module and a feedback control module. The main energy generation module outputs a high-frequency main waveform for tissue cutting or blood coagulation; the modulation signal generation module is used for generating a modulation signal, and the modulation signal comprises one of a multi-cosine signal or a multi-frequency sweep-frequency signal and a pseudo-random sequence; the output superposition module is used for superposing the modulation signal into the main waveform; the signal acquisition module synchronously acquires tissue voltage and current signals after the modulation signal is loaded; the impedance calculation module is used for performing frequency domain analysis on the voltage and current signals acquired by the signal acquisition module, extracting frequency components corresponding to modulation signals by using fast Fourier transform (FFT), phase lock detection (PLL) or a time-frequency analysis algorithm, and performing frequency domain analysis on multi-cosine signals or frequency sweep signals; by comparing the amplitude ratio and the phase difference of the corresponding frequency components of the modulation signal output end and the response end, the impedance Z = RZ < Z of the measured tissue is inverted according to the known reference impedance, and Z is the impedance of the measured tissue; rZ is the amplitude of the measured impedance and reflects the magnitude of the impedance; < Z represents the phase difference between the voltage and the current; for a pseudo-random sequence signal, a matched filter is used for carrying out related detection on an input signal, and a pseudo-random sequence value is extracted so as to obtain a system signal and control data; a feedback control module adjusts the output power or the cutting / coagulation mode of the electrosurgical equipment in real time according to the tissue impedance obtained through calculation and the dynamic change of the tissue impedance; wherein the dynamic change is a group of dynamic sequence values of the impedance of the measured tissue from the time dimension. By means of the design, real-time accurate measurement can be achieved, the anti-interference capability is high, errors are small, and efficient and safe cutting / blood coagulation can be achieved.

This invention relates to the field of medical hyperspectral image processing technology, and discloses a medical hyperspectral image classification method based on removing undesirable bands. The method includes: converting a three-dimensional medical hyperspectral image into a two-dimensional image; calculating the matched filter weight and information entropy weight for each band of the two-dimensional image; obtaining a fusion weight based on the matched filter weight and information entropy weight; sorting all bands of the two-dimensional image based on the fusion weight and target contribution, and filtering out undesirable bands; and performing classification operations on the two-dimensional image after removing undesirable bands. Based on the principles of matched filters and information entropy, the method calculates the average value of the absolutely normalized matched filter weights, and simultaneously calculates the average weight of the information entropy. The two weights are fused to evaluate each band for filtering, thus reducing the computational resource requirements and improving computational efficiency while ensuring classification accuracy.

The application provides a contrast image two-stage segmentation method, an electronic device, a processing system and a storage medium. First, an initial contrast image is acquired. Then, the initial contrast image is segmented according to a matched filter algorithm to obtain a first segmentation result. Finally, the initial contrast image and the first segmentation result are input into a pre-established segmentation model to obtain a second segmentation result of the contrast image. The pre-established segmentation model is used for denoising and breakpoint completion of the first segmentation result according to the initial contrast image. The contrast image is segmented according to a traditional matched filter algorithm first, and then the segmented image and the original image are input into the segmentation model for comparison, so as to remove the noise generated in the segmentation process and make up for the breakpoints caused by pixel loss, thereby effectively improving the accuracy of contrast image segmentation.

This invention provides a method and system for fault location and impedance estimation in distribution networks based on improved electromagnetic time reversal. The method includes: constructing an electromagnetic transient model of the distribution network under test; setting several potential fault locations and fault impedances in the distribution network under test; performing simulations using the electromagnetic transient model for each combination containing fault location and fault impedance to obtain the transfer function from the fault location to a preset measurement point; constructing a standardized matched filter signal library based on the transfer functions of all combinations; when a fault occurs in the distribution network under test, acquiring and differentiating the voltage response at the measurement point; obtaining the estimated time of the fault occurrence and the tolerance of the transient propagation time uncertainty in the distribution network under test to determine a time window; within the time window, calculating a score for each combination based on the differentiated signal and the standardized matched filter signal library, and taking the combination corresponding to the highest score as the fault location result.

The invention discloses a distance estimation method based on matched filter design under a pulse pressure system, and the method comprises the implementation steps: processing an ideal echo signal used for deducing a conventional pulse pressure matched filter through a low-pass filter in a radar receiver; performing time flipping and conjugate operation on the processed signal to obtain a corrected matched filter; performing pulse compression on an echo signal output by the radar receiver by using the corrected filter to obtain a distance unit where a target is located, and intercepting corresponding time width data; and constructing a corrected matched filter bank, and performing pulse pressure estimation on the intercepted time width data by using a sliding window pulse pressure algorithm to estimate a target distance. The corrected matched filter is more matched with the echo signal output by the low-pass filter, the precision of target distance estimation is improved, certain robustness is achieved, and the application range is wider.

The invention relates to an anti-interference method for SSFA-MCPC signal combined segmented mismatched filtering, and the method comprises the steps: designing the waveform of an SSFA-MCPC signal, carrying out the segmented chaotic phase coding of an MCPC signal in a time domain, and introducing frequency random agility in a frequency domain, thereby enhancing the randomness of the signal and the mutual shielding capability between sub-pulses, and achieving the anti-interference performance of the SSFA-MCPC signal. And the difference between the target echo and the ISRJ signal is effectively increased. On the basis, a segmented mismatch filtering method is adopted to process echoes, and interference suppression is realized by constructing a sub-pulse matched filter bank, utilizing the pulse pressure peak value difference of interfered and non-interfered sub-pulses and combining an Otsu algorithm to adaptively identify and reject the interfered sub-pulses and reconstructing matched filters. According to the method, three typical ISRJ patterns can be effectively suppressed, interference parameter prior is not needed, the calculation complexity is low, an effective solution is provided for radar interference resistance, and the method has good engineering application prospects.

The invention discloses a vertical measurement ionogram O / X wave separation method based on polarization matched filtering, and the method comprises the steps: obtaining a dual-channel complex signal, and carrying out the incoherent accumulation to obtain echo intensity; using an OS-CFAR detector and morphological processing to generate a mask; calculating a phase difference based on the mask, and fitting through a double-Gaussian mixture model to obtain O-wave and X-wave characteristic phases; estimating a complex polarization ratio; constructing a polarization matched filter weight vector, multiplying the polarization matched filter weight vector with the dual-channel signal, and separating to obtain an O / X wave complex signal matrix; a separated ionogram is generated through amplitude calculation and detection. The method does not depend on circular polarization hypothesis, actual polarization parameters can be directly estimated, high-precision separation is achieved through polarization matched filtering, and robustness and accuracy are improved.

The invention relates to the field of radar signal processing, in particular to a detection integrated waveform design method based on information receiving and transmitting interaction, which comprises the following steps of: acquiring target characteristics, and estimating or predicting the target characteristics at the current moment; the method comprises the following steps: pre-modulating an original transmitting signal according to target characteristics, and designing a pre-coded transmitting signal; transmitting and receiving the pre-coded transmitting signal; and detecting an original emission signal by adopting a matched filter. According to the method, the target scattering characteristics are acquired in advance, the signals are actively subjected to pre-compensation at the transmitting end, and the transmitted signals are subjected to pre-coding customization design, so that adverse effects caused by target multi-scattering-point interference can be actively counteracted, and the problems of echo energy attenuation and dispersion caused by target multi-scattering-point interference in the prior art are solved.

The invention discloses a folding clutter suppression method based on a frequency agility radar, and the method comprises the steps: setting the pulse number of a frequency agility pulse sequence, a frequency hopping interval and a frequency hopping coefficient of each frequency agility pulse signal, and transmitting a plurality of frequency agility pulse signals; calculating the carrier frequency of the echo signal received by the frequency agility radar according to the frequency hopping interval and the frequency hopping coefficient; filtering the echo signal by using a frequency domain filter corresponding to the echo signal carrier frequency, and outputting the filtered echo signal; respectively performing impulse response and convolution processing on the time domain and the frequency domain of the filtered echo signal by using a matched filter, and outputting the echo signal after matched filtering; and sparse reconstruction is carried out on observation signals in the sparse reconstruction model by using an orthogonal matching pursuit algorithm or an alternating direction multiplier method to obtain sparse vectors, so that target signal energy is enhanced, non-matching interference components are suppressed, significant enhancement of weak and small targets is realized, and folding clutters and noise are suppressed.

The present invention relates a method of improving a radar system, a module for improving a radar system and an improved radar system that are more efficient than current radar systems and methods of using same. Specifically, in the context of space-time adaptive processing at high angle-doppler resolutions, this advanced radar system utilizes an improved estimator of the interference covariance matrix together with the plug-in whiten-then-match filter. This improvement (a) roughly optimizes the output signal-to-interference-plus-noise, thereby increasing the probability of accurately detecting targets' angular positions and radial velocities, (b) maintains a roughly constant, and thus controllable, false alarm rate, and (c) sometimes associates data preprocessing steps with a Reed-Mallett-Brennan detection loss, providing a guideline for rejecting certain preprocessing steps. Collectively, these advancements signify a considerable leap forward in radar technology.

This invention provides a method and system for detecting ships using spaceborne ship monitoring radar, comprising: setting the pulse repetition frequency of the sea-penetrating radar on a zebra map; setting the sea-penetrating radar transmission signal; transmitting the signal and acquiring the sea-penetrating echo according to the settings; calculating the range ambiguity set where the main ambiguity energy is located; suppressing land ambiguity for the range ambiguity in the range ambiguity set; and detecting ships in the effective observation area of ​​the sea-penetrating echo after land ambiguity suppression. This invention noise-enhances the echo signal, solving the problem of false alarm detection and effectively improving the observation performance of space-based sea-surface detection radar; by using signal encoding and existing SAR image databases for range ambiguity suppression techniques, and by using a matched filter corresponding to the effective observation area to achieve range focusing in the effective observation area, it solves the problem of high range ambiguity requirements and realizes a spaceborne radar system for ship monitoring with low false alarm rates.

This invention discloses a high-speed blood flow Doppler measurement method and system for miniaturized ultrasound catheter probes. It employs a high-pulse repetition frequency complementary Golay-coded pulse sequence to replace continuous wave transmission, achieving a distance-dimensional information-discarding equivalent CW effect through extremely high PRF combined with range-gate coherent summation. Pulse compression processing gain is obtained through Golay BPSK encoding excitation. A pulse-by-pulse A / B alternating transmission strategy is used, with each physical pulse independently extracting Doppler samples using a matched filter corresponding to the codeword. Time-division multiplexing of pulse modes enables full-aperture transmission and reception, eliminating TX-RX acoustic leakage. This invention achieves a comprehensive signal-to-noise ratio gain of approximately 31 dB without exceeding the thermal load of traditional CW, restoring clinically usable CW equivalent Doppler spectra on ICE catheters, and can be implemented through firmware upgrades on existing PW Doppler hardware.

The invention discloses a deep-space high-dynamic low-bit-rate signal demodulation tracking processing system and method, and the method comprises the steps: firstly outputting a high-precision carrier tracking signal based on an input deep-space high-dynamic low-bit-rate signal baseband I / Q signal; secondly, weighting the high-precision carrier tracking signal to obtain an optimized signal; then, multi-channel processing is carried out on the optimized signal, an optimal channel is selected, and the carrier deviation range of the optimal channel is compressed; and finally compensating the phase of the high-precision carrier tracking signal, and outputting a high-precision demodulation result of the deep-space high-dynamic low-bit-rate signal. According to the invention, through introduction of a weighted matching filter, multi-channel coarse and fine estimation combined processing and small-sampling high-frequency multiplication clock multiplexing demodulation tracking, a deep-space high-dynamic and low-code-rate demodulation tracking processing function is completed.

The objective is to provide an information processing device, system, method, and program that can easily prepare radar images used for training a learning model. [Solution] The information processing device according to the embodiment comprises an acquisition means, a first generation means, and a second generation means. The acquisition means acquires a radar signal and a first observation signal based on the reflected wave signal from a radar device equipped with a plurality of antennas configured to transmit a radar signal and receive a reflected wave signal based on the reflected wave of the radar signal. The first generation means generates a first radar image by performing a convolution integral of the first observation signal and a first matched filter. The second generation means generates a second radar image by performing a convolution integral of the first observation signal and a second matched filter. The first and second radar images are used as training data for a learning model to learn how to detect an object on which a radar signal is transmitted.