20 results about "Pulse spectrum" patented technology

The invention relates to the technical field of pulse load energy optimization control, in particular to a pulse type ultra-low power consumption energy management system based on a super capacitor, which comprises a pulse spectrum analysis unit, a capacitor bank dynamic tuning unit and a charge state compensation unit, a pulse spectrum analysis unit extracts a load pulse dominant frequency component through a window function weighting algorithm to generate a target frequency value, and a capacitor bank dynamic tuning unit inquires a mapping table according to the target frequency to adjust series-parallel connection combination of the super capacitors and injects a reverse reactance component to offset a resonant impedance difference value. And the charge state compensation unit predicts the residual charge quantity by using a Kalman filter, and triggers a charge redistribution strategy in a non-pulse period, thereby solving the problems of insufficient dynamic impedance matching and low charge balance efficiency in the traditional technology, realizing high-efficiency and low-consumption management of the energy of the super capacitor, improving the energy transmission efficiency, and reducing the energy consumption. And the endurance time of the equipment is prolonged.

The invention relates to the technical field of ultrafast laser, and discloses a negative chirp management method and device of a laser and a medium. The method comprises the following steps: pre-processing a seed pulse, outputting the seed pulse through a mode-locked optical fiber oscillator, and primarily amplifying the seed pulse through a single-mode gain optical fiber; temperature tuning negative chirp introduction is carried out, a chirp fiber grating is packaged in a temperature tuning device, and the temperature of a semiconductor chilling plate is linearly increased within a preset range, so that the second-order dispersion amount of the chirp fiber grating is changed, and controllable negative chirp is introduced into a pulse; carrying out nonlinear amplification and spectrum broadening, inputting the pulse introduced with the negative chirp into a multimode gain fiber, injecting pumping energy into the multimode gain fiber, and broadening the pulse spectrum width to be greater than a preset width by utilizing the synergistic effect of self-phase modulation, dispersion and gain; pulse width compression is carried out, and the pulse after spectrum broadening is adjusted through a transmission-type grating pair compressor, so that the ultra-narrow pulse width is obtained.

The application relates to the technical field of discharge signal collection, in particular to a high-voltage cable partial discharge signal synchronous collection method and system, which comprises the following steps: based on a multi-channel high-speed double-ADC architecture, synchronously collecting ground loop current signals and high-frequency current signals in the operation process of a high-voltage cable; calculating pulse frequency spectrum consistency and mutation phase fluctuation to obtain a discharge loop current abnormality; determining the pulse periodicity of the high-frequency current signals; extracting harmonic frequency parameters and energy attenuation parameters of the high-frequency current signals, calculating a harmonic abnormality, combining the pulse periodicity to obtain a pulse harmonic abnormality factor; performing weighted summation on the discharge loop current abnormality and the pulse harmonic abnormality factor to evaluate the reliability of the synchronously collected signals, and outputting a synchronous collection result of the high-voltage cable partial discharge. Therefore, the accuracy of the synchronous collection of the partial discharge signals is improved.

The application discloses a kind of numerical simulation method and system of saturable absorber mode-locked fiber laser, method includes the following steps: setting simulation parameter;Input a noise pulse as the initial pulse of simulation system;The numerical solution of nonlinear Schrödinger equation is calculated by improved step-by-step Fourier method, and the evolution result that pulse is transmitted in optical fiber is obtained;The shaping effect of saturable absorber to pulse is simulated using the transmissivity function of saturable absorber;Coupler solver redistributes the energy of pulse;Post-processing module saves the data when pulse stops running, and it is drawn into the curve graph and three-dimensional graph of pulse shape and pulse spectrum.The simulation method and system disclosed in the application can solve the problem of low calculation precision of dispersion term in fiber laser simulation, greatly improve the simulation accuracy, and can more accurately predict the output characteristics of mode-locked fiber laser.

The application relates to the technical field of communication interference elimination, in particular to a pulse interference elimination method for a power carrier communication chip, which comprises the following steps: acquiring carrier signals of each communication node in a power carrier communication network and the length of a power line between any two communication nodes; acquiring suspected pulse noise points; calculating pulse noise weights of the suspected pulse noise points; intercepting each suspected pulse signal in the carrier signal; obtaining a pulse noise spectrum diagram of each communication node; calculating line loss ratios between any two communication nodes; obtaining a comprehensive pulse spectrum diagram of each communication node; calculating an attenuation ratio of each frequency position; obtaining a noise suppression spectrum diagram; and obtaining a carrier signal after noise suppression based on the noise suppression spectrum diagram, so as to eliminate pulse interference in the carrier signal. The application dynamically filters the frequency domain characteristics of the carrier signal, and improves the communication quality of the power carrier communication chip.

The invention provides a near-fault seismic motion vector type intensity index construction method, and belongs to the technical field of structural toughness anti-seismic analysis, and the method comprises the steps: calculating a value of an ideal speed pulse signal acceleration response spectrum at a structural basic period under a 5% damping ratio, and taking the value as a near-fault seismic motion speed pulse spectrum characteristic representation parameter; calculating the normalized total speed pulse duration, and representing the influence of the multi-speed pulse generation time process on the low-cycle fatigue damage of the structure; the two parameters are combined into a vector, namely the near-fault multi-speed pulse record vector type intensity index. According to the method, the structure dynamic response is directly associated with the velocity pulse frequency spectrum characteristic, meanwhile, the pulse generation time process parameters are introduced for the first time, the structure fatigue damage is associated with the velocity pulse generation process in the seismic oscillation, the near-fault multi-velocity pulse seismic oscillation intensity can be effectively represented, and the accuracy of the seismic oscillation intensity is improved. And the influence on the seismic response of the structure can be measured more accurately.

This invention relates to a method for measuring the neutron energy spectrum of a multi-sphere neutron spectrometer based on pulse spectrum segmented response. It simulates the pulse spectrum response of a single-energy neutron incident multi-sphere spectrometer, segments it according to different energy ranges, and obtains a new response matrix. Then, it segments the measurement results Y of the multi-sphere spectrometer according to the same energy range to obtain n corresponding segmented measurement results Y1, Y2, ..., Y... n Let k1, k2, ..., k be the numbers respectively. n 1-dimensional vectors, combine them into a k1+k2+…+k n The new vector of the measurement results is used to solve for the neutron energy spectrum X according to the formula. Using the method disclosed in this invention, the response of a multi-sphere neutron spectrometer is simulated and statistically analyzed across energy ranges, and the measurement results of the multi-sphere neutron spectrometer are processed. Without increasing the number of spheres in the multi-sphere neutron spectrometer, more linearly independent equations are obtained, resulting in richer energy spectrum information. This improves the reliability and accuracy of solving the neutron energy spectrum without incurring additional costs.

This invention discloses a tunable saddle-shaped spectrum generation device and method, belonging to the field of precision machining. It includes: a pump source, a resonant cavity with overall positive dispersion, a mode-locking device, a dispersion management device, and a spectral adjustment component. The pump source excites a gain fiber to generate laser light. The mode-locking device outputs a mode-locked pulse, and the dispersion management device provides positive dispersion. Working in conjunction with the nonlinear effect of self-phase modulation within the cavity, the mode-locked pulse spectrum is directly shaped into a saddle-shaped spectrum with a central depression. The spectral adjustment component achieves flexible tuning of the center wavelength and bandwidth of the output spectrum by adjusting the relative positions of the diffraction grating and the fiber collimator. This invention actively generates a tunable saddle-shaped spectrum from the source, eliminating the need for complex modulation elements in the amplification link. It allows for precise pre-compensation of the gain characteristics of subsequent amplifiers, effectively suppressing gain narrowing effects. It has the advantages of compact structure, low cost, high stability, and high energy utilization.

The invention provides a pulse spectrum synthesis system and method, and relates to the field of spectrum synthesis. The pulse fiber laser sub-beam comprises a pulse seed source used for outputting pulse laser as signal light; the continuous seed source is used for outputting continuous laser as reference light, the wavelength of the reference light is different from that of the center pulse of the signal light, and the average power of the reference light is smaller than that of the signal light; the wavelength division multiplexer is respectively connected with the pulse seed source and the continuous seed source and is used for synthesizing the signal light and the reference light into one path as synthesized light; and the signal amplifier is connected with the wavelength division multiplexer and is used for amplifying the signal light and the reference light to form amplified synthetic light. Reference continuous light is coupled into the amplifier through the optical coupler, so that amplification of continuous components of signal light is restrained, the number of upper-energy-level particles is consumed, ASE is restrained, the signal-to-noise ratio of laser output is increased, and the efficiency of the laser is improved.

The application discloses a kind of based on time-frequency chart's graph signal detection method, terminal equipment and storage medium, the method includes the following steps: obtaining signal time-frequency chart, Fourier transform is carried out after filtering and binarization to it in time direction, the maximum value position of each column is counted and clustered, and the class with bandwidth is too narrow and the column discontinuous in class is removed;The corresponding column of each class is summed in frequency direction to obtain pulse envelope, and then the start and end column of the pulse spectrum envelope corresponding to each class is obtained, which is compared with the start and end column of each class after clustering, to find the class with the smallest error;Iterate until the error of current calculation result and previous calculation result tends to be stable, then determine the frequency band of stable result, that is, whether the signal is the target signal can be judged.The application is applied to communication technology and electronic countermeasure field, not only less calculation, and high-precision detection can be carried out on graph signal under low signal-to-noise ratio condition, but also can filter out part of interference signal, false alarm rate is lower.

A real-time measurement method and apparatus for long-wave infrared pulse spectra based on nonlinear frequency upconversion is disclosed. The method utilizes a non-oxide semiconductor crystal as the nonlinear medium and employs a narrowband pulse with a center wavelength in the range of 2-2.5 μm as the sampling light. This pulse is summed with the long-wave infrared pulse to be measured, and the resulting summed pulse is received and detected by a near-infrared real-time spectrometer. The combination of the selected sampling light wavelength and the selected crystal generates an ultra-wide phase-matching bandwidth. Through a linear frequency mapping relationship, the spectrum of the long-wave infrared pulse to be measured can be inverted from the detected summed pulse spectrum. By analyzing the spectrum acquired by the near-infrared spectrometer in real time, the spectrum of the long-wave infrared pulse to be measured can be directly and in real-time reconstructed. This invention overcomes the limitations of Fourier transform spectrometers and traditional grating spectrometers in real-time measurement, achieving real-time, mechanical-scan-free measurement of long-wave infrared pulse spectra without requiring a specific repetition frequency for the long-wave infrared pulse.

The application provides a multi-pass cell structure light pulse spectrum shape consistency regulation compression method and system. The method makes the structure light pulse multiple round trip propagation in the multi-pass cell and realizes the spectrum broadening dominated by self-phase modulation through the nonlinear medium, carries out spatial-spectrum interference measurement on the measured light after the spectrum broadening of the multi-pass cell and the dispersion compensation, restores the wavelength resolution spatial complex light field data, and establishes the evaluation index for representing the spectrum shape spatial consistency with the spectrum overlap index V. According to the evaluation index, the input structure light parameters, the multi-pass cell propagation parameters and the dispersion compensation parameters are feedback adjusted, so that the quantitative evaluation and optimization control of the structure light pulse spectrum broadening process and the compression output quality are realized, and the output pulse with the target spectrum width, the higher spectrum shape spatial consistency, the good compressibility and the higher peak power is obtained.

The invention relates to a device (1) for characterizing the spectral phase of at least one single photon of a signal (5), comprising a first light source (2) for generating at least one pump pulse (3) with a pump pulse spectrum, a supply line (4') for a second light source (4) for supplying at least one signal pulse (5) with a signal pulse spectrum, a pulse shaper (6) for shaping the pump pulse (3) in such a way that two phase-different spectral frequency bins (12) of the pump pulse (3) are transmitted with an adjustable frequency, a mixing device (7) for mixing the shaped pump pulse (3) with the signal pulse (5) and outputting at least one first part (8) of the signal pulse spectrum, with the first part (8) comprising an overlap (11) of a frequency component of the signal pulse spectrum with the adjustable frequency of the pump pulse (3), a measuring unit (9) for measuring the intensity of the first part (8) of the signal pulse spectrum and coding a second part of the signal pulse spectrum, with the second part comprising the overlap (11) of the signal pulse spectrum shifted by a predetermined offset and the pump pulse spectrum, and an evaluation unit (10) for reconstructing at least one phase and / or one coherence property of the signal pulse (5). In this way, a simple, fast and reliable characterization of the spectral phase and coherence properties of at least one single photon light pulse is made possible.

The application discloses a frequency optimization method and device based on spectrum sensing, and belongs to the field of wireless communication, which comprises the following steps: firstly, starting the spectrum sensing function before the beginning of the current receiving time slot; continuously performing frequency configuration during the spectrum sensing process; after the frequency configuration, sampling and mixing the radio frequency signal corresponding to the current frequency, and performing low-pass filtering to output the baseband signal; calculating the average power of the baseband signal in the time domain, calculating the fast Fourier transform in the frequency domain, and then taking the modulus and searching the peak value to complete the spectrum sensing calculation in the time-frequency two dimensions; finally, according to the sensing calculation result of the time-frequency, configuring the subsequent frequency, and performing the frequency optimization according to the optimization strategy to output the final optimized frequency. The application does not occupy the system bandwidth, does not depend on the prediction and cooperation among nodes, and only needs the receiving node to complete the synchronous pulse spectrum sensing and frequency optimization with a low calculation amount, so that the frequency domain interference is avoided, and the synchronization capability is improved.

A transmitter includes a first circuit to generate multiphase pulses, and a second circuit to mix a set of in-phase (I) data and quadrature (Q) data with the multiphase pulses and to generate an output radiofrequency (RF) signal. The multiple pulses include multiple I pulses and multiple Q pulses each comprising a pulse that includes a duty cycle such that a first null appears at a third harmonic frequency in a frequency spectrum of the pulse.

The invention discloses a frequency optimization method and device based on spectrum sensing, and belongs to the field of wireless communication, and the method comprises the steps: firstly, starting a spectrum sensing function before the start of a current receiving time slot; frequency configuration is continuously carried out in the spectrum sensing process; after the frequency is configured, sampling frequency mixing and low-pass filtering are carried out on a radio frequency signal corresponding to the current frequency, and a baseband signal is output; calculating the average power of the baseband signal in the time domain, calculating the modulus and the retrieval peak value after fast Fourier transform in the frequency domain, and completing the spectrum sensing calculation of two dimensions of time and frequency; and finally, according to a time-frequency sensing calculation result, configuring a subsequent frequency, performing frequency optimization according to an optimization strategy, and outputting a final optimization frequency. The method does not occupy the system bandwidth, does not depend on inter-node prediction and cooperation, and can complete synchronization pulse spectrum sensing and frequency optimization only by using a low calculation amount by the receiving node so as to avoid frequency domain interference and improve the synchronization capability.

The invention provides an intermediate infrared femtosecond laser pulse spectrum measurement device. The intermediate infrared femtosecond laser pulse spectrum measurement device comprises a beam splitter, a nonlinear frequency up-converter, a quasi-monochromatic pulse generator, a sampler, a first spectrograph, a delay regulator, a focuser, a sum frequency device and a second spectrograph, after a laser pulse to be measured is split by the beam splitter, a first laser beam sequentially passes through the nonlinear frequency up-converter and the quasi-monochromatic pulse generator to form a quasi-monochromatic pulse; the quasi-monochromatic pulse is extracted and sliced by the sampler and enters a first spectrograph for calibrating the central wavelength; after the second laser beam passes through the delay regulator, the second laser beam and the quasi-monochromatic pulse pass through the focuser to generate nonlinear sum frequency in the sum frequency device, and a sum frequency pulse is generated; and the sum frequency pulse signal is received by the second spectrograph to obtain a copy spectrum of a near-infrared domain, and an original spectrum of the intermediate infrared femtosecond pulse to be detected is given after data processing. The device has the advantages of high measurement precision, high signal-to-noise ratio, real-time performance and more compactness.

The application discloses a frequency-modulated laser pulse spectrum width calibration method and a calibration system based on a traversal correlation algorithm, and belongs to the field of laser signal processing. The frequency-modulated laser pulse spectrum width calibration method draws a first relationship curve between a measured spectrum width and a calibration spectrum width based on measurement data, and finally determines the calibration spectrum width of a subsequent laser pulse to be measured by using the first relationship curve. The application establishes a connection between a medium-precision measurement spectrum and a theoretical simulation spectrum, the calibrated spectrum width more reflects the physical nature of phase modulation relative to the -3dB spectrum width, and the data obtained by the calibration method and the calibration system has strong correlation (R>0.9), high linearity and high confidence, and the data is more reliable. Meanwhile, the calibration method and the calibration system provided by the application reduce the use frequency of a high-precision spectrometer, reduce the use cost, reduce the dependence on high-end instruments, and have high economic value.

This invention discloses a method, system, device, and medium for determining the low-temperature charging compensation time of electric vehicles. The method includes: acquiring a first charging current pulse spectrum and a second charging current pulse spectrum, wherein the first charging current pulse spectrum is the pulse spectrum of the charging current at a first preset temperature, and the second charging current pulse spectrum is the pulse spectrum of the charging current at a second preset temperature, and the first preset temperature is lower than the second preset temperature; determining the current crossover point of the first and second charging current pulse spectra; determining the target state of charge based on the current crossover point; determining a first charging time and a second charging time based on the target state of charge; and determining the compensation time based on the first and second charging times. This invention solves the technical problem of being unable to estimate the charging time of a vehicle-level power battery under low-temperature conditions.

The present application relates to the technical field of geophysical environment exploration, and specifically discloses a frequency-domain controllable source electromagnetic emission pulse amplitude control method and system, the method comprising constructing a pseudo-random pulse sequence basic framework and an exploration target adaptive spectral function curve according to exploration requirements; in the basic framework, the lowest frequency of each basic unit adopts adaptive frequency error design, and the basic unit is composed of a series of sine waves with different frequencies; the pseudo-random pulse sequence is subjected to frequency spectrum ratio-based iterative amplitude adjustment, so that the frequency spectrum amplitude approximates the expected spectral function curve; the time domain waveform of the amplitude-adjusted pseudo-random pulse sequence is subjected to amplitude limiting to generate a bipolar pseudo-random pulse; the present application realizes combination of different frequency point amplitudes by nonlinear control of emission pulse spectral distribution, improves measurement precision, and expands the emission pulse excitation range.