102 results about "Spectral width" patented technology

The invention discloses a composite precipitation cloud layer identification method based on a laser radar-cloud radar, and the method comprises the steps: obtaining the observation data of the laser radar and the cloud radar, and carrying out the data matching of the observation data; processing a signal of the laser radar in a height interval of 18-20 km to obtain a preprocessed laser radar signal; performing laser radar cloud boundary identification based on a VED algorithm, and endowing different laser radar cloud scores according to the signal attenuation rate and the signal gradient; removing earth surface clutters by using a threshold method based on observation of spectral width and Doppler velocity; carrying out cloud radar significant echo recognition based on a threshold method, and determining the cloud score of the cloud radar according to different reflectivity factor signal intensities; determining a light rain area and a heavy rain area according to the Doppler velocity; cloud layer boundary information and a hairy rain area are obtained through cloud layer recognition result fusion, and cloud layer recognition and rainfall area recognition are completed; according to the invention, the accuracy of weather prediction is improved.

The invention provides a wind profile radar spectrum peak estimation method based on a three-parameter dynamic cost function, and the method comprises the steps: 1, carrying out the preprocessing of distance and Doppler spectrum data, and carrying out the three-point moving average smoothing; step 2, noise level estimation based on statistics is carried out; step 3, carrying out candidate spectrum peak selection based on space Doppler window smoothing; 4, performing dynamic weight calculation based on covariance matrix eigenvalue decomposition; step 5, constructing a three-parameter cost function of a distance spectrum peak value RSP power item, a continuity item and a spectrum width consistency item, and performing optimization; and step 6, outputting the optimal spectrum peak trajectory to form a complete wind speed profile trajectory. According to the method, the spectrum peak identification precision and stability in a complex environment can be improved, and the u and v wind correlation coefficients of the estimation method are verified to reach 0.880 and 0.879 through a data set disclosed by an atmospheric radiation measurement website.

The invention discloses a weather radar meteorological echo and non-meteorological echo identification system, and belongs to the technical field of meteorological radar signal processing. The method comprises the following steps: acquiring radar original data containing reflectivity factors, radial velocity and spectral width, and generating a three-dimensional feature matrix through format standardization, combined noise removal, neighborhood interpolation filling and parameter normalization; constructing a sample set through professional labeling, consistency verification and multi-dimensional data enhancement; a deep convolutional neural network containing a ResNet50 feature extraction module, a CBAM double attention module and a classification output module is constructed, and a binary cross entropy loss function, an Adam optimizer and an early stop regularization strategy are adopted for training optimization; to-be-recognized data is preprocessed and then input into the model, and a classification result and confidence are output. The method does not need manual feature design, significantly improves the recognition stability of echoes difficult to distinguish in a complex scene, adapts to different radars and regional environments, and meets the real-time processing requirements.

The invention provides a sea wave spectrum prediction method based on deep learning, and belongs to the technical field of sea wave spectrum prediction, and the method comprises the steps: calculating an accumulated energy function and relative accumulated energy based on sea wave spectrum data, and fixedly dividing a frequency domain into a plurality of subintervals according to a preset energy percentile threshold value; for each sub-interval, extracting at least one physical feature of segment energy, center frequency, peak frequency and spectral width of the interval, and combining the original spectral vector of the interval with the extracted physical features to form an input feature vector of the sub-interval; an independent neural network model is constructed and trained for each subinterval, the input feature vector of the corresponding subinterval is used as input, and the predicted spectrum vector of the subinterval is output; and splicing the prediction spectrum vectors output by the neural network of each subinterval according to a frequency sequence, performing weighted average processing at the junction of the subintervals, and performing reconstruction to obtain a complete sea wave spectrum prediction result.

The present application relates to the technical field of weather radars, and discloses a fully automatic calibration method for a weather radar. In the method, multiple sets of calibration differential signals are injected into a receiver of a weather radar to be calibrated, wherein at least two sets of calibration differential signals differ in injection power, at least two sets of calibration differential signals differ in frequency offset, and at least two sets of calibration differential signals differ in spectral width; then, by combining the injection power, frequency offset, and spectral width of each set of calibration differential signals and measured values of intensity, velocity, and spectral width under the corresponding calibration differential signals, the unified calibration of the intensity, velocity, spectral width, differential reflectivity factor, and differential propagation phase shift can be accomplished. The method innovatively unifies various radar parameters into a single calibration process while ensuring comprehensive calibration of those radar parameters, thereby greatly reducing calibration time and items, optimizing the calibration process, and improving the calibration efficiency.

This invention discloses a design method for a plane-multiplying relay structure of a wide-spectrum, wide-swath hyperspectral imaging telescope, relating to the field of optical design technology. The method includes establishing a model for realizing a controllable aberration-multiplying relay structure. This model consists of four closely related parts: field segmentation, plane multiplication, telecentricity adjustment, and field curvature / distortion adjustment. Based on this model, the interrelationships between the number of field segmentations, plane multiplication rate, image-side telecentricity adjustment, field curvature / distortion adjustment, and relay structure parameters of the hyperspectral imaging system are clarified. Based on these parameter relationships, a design method for the initial relay structure is further proposed. Using the plane-multiplying relay structure of this invention, wide-spectrum, wide-swath hyperspectral imaging is achieved, breaking through the technical bottleneck of traditional telescopes' difficulty in connecting multiple large-field-of-view spectrometers and large-scale detectors.

The application provides a differential-based white light lensless single-frame weakly conjugate reconstruction method, which can realize weakly conjugate image reduction and improve single-frame imaging resolution in a white light lensless imaging system without using additional elements and complex algorithms. The method comprises the following steps: step one, obtaining spectral distribution information of a system light source by using a spectrometer and performing differential processing to obtain a reconstruction wavelength; step two, performing preprocessing on a collected single-frame image by using a hologram average value reduction method; step three, generating light intensity diagrams of different defocusing surfaces by using an angular spectrum propagation formula, and determining a defocusing distance range based on a definition discrimination factor; and step four, calculating differential distribution on different focal planes in the distance range obtained in step three based on numerical differentiation, and obtaining a final result by selection. The application can reduce the requirement of spectral width of a traditional lensless microscope, effectively reduce the cost of the system, improve the imaging resolution of the white light lensless microscope, and reduce the weakly conjugate image in the case of single-frame image collection.

A medical device that functions as a stylet is described. The medical device can include an insulating layer (or jacket) that encapsulates both a multicore optical fiber and a conductive medium. The optical fiber can include a cladding and a plurality of core fibers spatially arranged within the cladding. Each of the core fibers can include a plurality of sensors distributed along a longitudinal length of the corresponding core fiber, and each of the sensors can be configured to: (i) reflect light signals having different spectral widths based on received incident light, and (ii) alter a characteristic of the reflected light signals for determining a physical state of the multicore optical fiber. The conductive medium can provide a path for electrical signals detected at a distal portion of the conductive medium. The conductive medium can be concentric with the cladding, but can be separate from and adjusted to the cladding.

The application provides an airborne dual-band weather radar detection method, which comprises the following steps: S1: adopting a dual-band common-aperture antenna to time-divisionally emit X-band electromagnetic waves and Ka-band electromagnetic waves; S2: a weather radar receives the X-band electromagnetic waves and the Ka-band electromagnetic waves and performs ground clutter suppression; S3: calculating reflectivity Rrf x according to the X-band electromagnetic waves; S4: calculating reflectivity Rrf ka , velocity V ka and spectral width W ka ; S5: performing analysis on weather targets and displaying analysis results. The detection method realizes cloud detection by using the Ka band on the basis of meeting original X-band weather rainfall detection functions, realizes dangerous weather identification and dangerous area warning by comprehensively considering the spatial structure of the cloud and Doppler information, marks weather seriously threatening flight safety in a display picture, and reminds pilots to pay attention. The detection method comprehensively improves the detection perception and display capability of the airborne weather radar on various weathers, further improves flight safety, and reduces unnecessary deviation.

An ultrasound system is disclosed that includes an ultrasound imaging device including a display screen, a processor and memory having stored thereon logic, and an ultrasound probe. The logic of the ultrasound imaging device, upon execution by the processor, can causes an alteration of content displayed on the display screen in accordance of with ultrasound probe movement-related data. The ultrasound imaging device can include a light source configured to provide incident light to the optical fiber cable, the optical fiber cable including a plurality of reflective gratings disposed along a length thereof. Each of the plurality of reflective gratings can be configured to reflect light with different specific spectral widths to provide distributed measurements in accordance with strain applied to the optical fiber cable. The ultrasound imaging device can obtain the ultrasound probe movement-related data through an optical fiber.

This invention relates to a dual-comb control system for a terahertz quantum cascade laser, comprising a first terahertz quantum cascade laser, a second terahertz quantum cascade laser, a first T-type biaser, and a second T-type biaser. The first terahertz quantum cascade laser operates in optical frequency comb mode, while the second terahertz quantum cascade laser operates above a threshold current. The first and second terahertz quantum cascade lasers emit terahertz light from each other. The first terahertz quantum cascade laser also functions as a detector to detect a mixing signal. The state of the mixing signal is switched by changing the power of the radio frequency signal generated by the radio frequency source. This invention enables the switching of the mixing signal between chaotic, unstable, and dual-comb states under high drive current, significantly improving the spectral width and application scenarios of the dual-comb system based on the quantum cascade laser.

This invention discloses a laser beam identification device and method for identifying whether a test beam is a first laser beam or a second laser beam, wherein the spectral widths of the first and second laser beams are different. The laser beam identification device includes a beam expander, an aperture, and a detector. The beam expander allows the output beam formed after the test beam passes through to be incident on a first and a second slit in the aperture. The output light from the first and second slits interferes. The detector is located on the light-emitting side of the aperture and is used to detect the light intensity at at least two positions, which are different positions along the direction of the interference fringes. Based on the light intensity at these at least two positions, the detector determines whether the light field distribution at these positions is a fringe distribution or a uniform field distribution, thereby determining whether the test beam is the first or the second laser beam. This invention has low cost, relatively small size, and low power consumption.

The present application discloses a multi-wavelength label signal processing method, a processor, and a storage medium. The method comprises: acquiring a service spectrum width of an optical service (S110); determining a carrier frequency according to the service spectrum width and a preset carrier frequency range (S120); performing modulation processing on wavelength information of the optical service according to the carrier frequency to obtain a single-frequency label signal or a dual-frequency label signal (S130); and sending the single-frequency label signal or the dual-frequency label signal to a signal receiving end, so that the signal receiving end obtains optical power and the wavelength information according to the single-frequency label signal or the dual-frequency label signal (S140).

The application discloses a kind of short-term wave height distribution characterization methods based on spectral width, it is related to marine engineering technical field, and the method comprises: based on the statistical parameter of given measured short-term sea state calculation spectral width factor;Wherein, statistical parameter includes spectral frequency, spectral peak frequency, energy density spectrum and energy density spectrum maximum;According to local measured data situation determines characteristic parameter;Wherein, local measured data includes the significant wave height under multiple groups of short-term sea state, three-one wave height, spectral frequency, spectral peak frequency, energy density spectrum and energy density spectrum maximum;Distribution parameter is calculated according to characteristic parameter;Based on spectral width factor and distribution parameter determine the exceeding probability of short-term wave height distribution, provide more accurate input parameter for the design and construction of related structure of nearshore engineering, ocean engineering, near island reef engineering, make preparation for the characterization of short-term wave height distribution and short-term wave height prediction.

Disclosed herein is a system that includes an ultrasound imaging probe having a first optical fiber integrated therein and a console optically coupled with the ultrasound imaging probe via a first elongate member. The console includes one or more processors and a non-transitory computer-readable medium having stored thereon logic, that when executed by the one or more processors, causes operations that can include providing an incident light signal to the first optical fiber via the first elongate member, receiving reflected light signals of different spectral widths of the incident light from the first optical fiber and the second optical fiber, processing the reflected light signals to determine a first three-dimensional (3D) shape extending along a length including at least portions of the first optical fiber and the second optical fiber, and causing rendering of an image of the first 3D shape on a display of the medical system.

The invention relates to the technical field of biological detection, and provides a biological tissue component detection device and a detection method. The biological tissue component detection device comprises a laser unit, a sample table, a polarization unit, a detector, a first scanner and a processor, the polarization unit is used for reflecting the S polarized light emitted by the laser unit to the biological tissue and filtering out the S polarized light in the mixed light reflected by the biological tissue; the detector is used for collecting light intensity of theta polarized light; the first scanner is used for acquiring space coordinates of each region of the biological tissue; and the processor is used for generating a polarization angle spectrum of the single region based on the light intensity and the polarization angle, generating a global polarization angle spectrum of the biological tissue based on the plurality of polarization angle spectrums and the plurality of space coordinates, and detecting the biological tissue based on a peak polarization angle, a spectrum width and a polarization extinction ratio of the global polarization angle spectrum. According to the biological tissue component detection device, spectrum similar substances in multiple industries can be distinguished, and the biological tissue distinguishing accuracy is improved.

The invention belongs to the technical field of lasers. The invention provides an all-fiber laser with adjustable pulse width and a pulse width tuning method. The all-fiber laser comprises a narrow-band dissipation soliton mode-locked fiber laser seed source, a first fiber isolator, a fiber amplifier, a second fiber isolator, an optical circulator and a dispersion element which are sequentially arranged along a light path. The seed source generates a mode-locked pulse with a fixed initial spectral width; the nonlinear effect intensity is controlled by adjusting the driving current of the pumping source, so that the spectrum broadening amount of the pulse in the amplification process is regulated and controlled, the variable total spectrum width is formed, the spectrum width is subjected to linear time-frequency mapping through a dispersion element with a fixed group delay dispersion value, and finally continuous and electric control adjustment of the output pulse width is achieved. The whole system adopts an all-fiber structure, has the advantages of high stability, compact structure, good tuning linearity and the like, and is suitable for industrial processing, sensing and scientific research application scenes needing flexible pulse width regulation and control.

The utility model discloses a wavelength tunable 2 [mu] m single longitudinal mode all-solid-state pulse laser, which belongs to the technical field of lasers, and comprises a pumping source, the output end of the pumping source is provided with a 1: 2 optical coupling system, the output end of the 1: 2 optical coupling system is provided with an input mirror, the output end of the input mirror is provided with a Tm: YAP crystal, and the Tm: YAP crystal is used for generating 2 [mu] m laser; the output end of the Tm: YAP crystal is provided with an acousto-optic modulator, the output end of the acousto-optic modulator is provided with an etalon, the output end of the etalon is provided with a birefringence filter, and the output end of the birefringence filter is provided with an output mirror. The wavelength tunable 2 [mu] m single longitudinal mode all-solid-state pulse laser is simple in structure, can stably generate 2 [mu] m laser, provides a wider wavelength tuning range and more direct tuning, and realizes narrower spectral width at the same time.

This application discloses an optical fiber, an optical amplifier, and an optical transmission network for expanding the gain spectral width of optical fiber signal amplification and achieving long-distance broadband transmission. The optical fiber provided in this application includes: a first doped layer, a second doped layer, and a cladding. The second doped layer is located outside the first doped layer, and the cladding is located outside the second doped layer. The second and first doped layers are composed of different materials. The cladding is used to reflect pump light, as well as first-band and second-band signal light, through its inner wall. The first doped layer is used to amplify the first-band signal light using the energy of the pump light. The second doped layer is used to amplify the second-band signal light using the energy of the pump light.

The application discloses a weather radar wind turbine clutter recognition method and system based on fuzzy reasoning, and belongs to the technical field of fuzzy reasoning. The monitoring area of a target weather radar is divided into multiple echo observation subunits according to distance gates and scanning azimuth angles, and the reflectivity factor, radial velocity, spectral width and differential reflectivity of each echo observation subunit are continuously acquired within a preset data acquisition time sequence. By analyzing the discrete characteristics of the reflectivity factor and the radial velocity in the time sequence, echo stability characteristic quantities are constructed, echo shape consistency characteristic quantities are constructed based on the consistency deviation of the spectral width and the differential reflectivity in the neighborhood, the echo stability characteristic quantities and the echo shape consistency characteristic quantities are subjected to fuzzy mapping, and the wind turbine clutter and meteorological echoes are distinguished and recognized through a fuzzy comprehensive judgment quantity, so that the accuracy and robustness of the wind turbine clutter recognition are improved, and the weather radar data quality control under complex background conditions is suitable.

The invention provides a fire hazard wind field and spread dynamic prediction method and system based on radar echo evolution characteristics. The method comprises the following steps: step 1, carrying out ground clutter suppression, radial high-frequency oscillation filtering, speed deblurring and time-space consistency check on reflectivity Z, radial speed V, spectral width W and dual polarization quantity of a plurality of weather radars; 2, under a three-dimensional variational 3DVAR framework, taking a numerical mode background field as prior, and performing inversion to obtain a boundary layer three-dimensional wind field; 3, establishing an anisotropic cellular automaton (CA) and live wire particle swarm coupling model under the constraints of a digital elevation model (DEM), combustible material types, water content and meteorological elements; 4, performing real-time correction and short-term and temporary extrapolation on the fire point and live wire states; and step 5, result output and early warning. By applying the technical scheme, the minute-level short-term and temporary prediction capability can be improved, and the safety of key assets such as power transmission channels is ensured.

This optical communication system comprises: an optical transmission unit that includes a light source for outputting laser light having a spectral width of 0.1 nm or greater in an oscillation spectrum and a signal generator for applying a modulation signal of 25 GBaud or greater to the light source, the optical transmission unit outputting a modulated optical signal in which the laser light is modulated by the modulation signal; and an optical fiber that is composed of a plastic which contains fluorine atoms in at least the core thereof, the optical fiber being such that the absolute value of material dispersion at a wavelength within the spectral width of the modulated optical signal is less than the absolute value of material dispersion in quartz glass, having a length of 100 m or less, having a GI-type refractive index distribution, and propagating the modulated optical signal.

The invention discloses a laser composite function treatment device based on an ultra wide band spectrum. According to the treatment device, smooth ultra-wideband spectrum laser is generated through femtosecond laser, two treatment functions can be achieved in the same set of treatment instrument, and the functions of the femtosecond laser treatment instrument are expanded; the overall size can be reduced by 1 / 2; the treatment device comprises a femtosecond laser, a polarization controller, a polarization beam splitter, a femtosecond light guide mirror, a pumping module, a super-continuum spectrum module, a narrow-band attenuator, a pulse width stretcher, a wavelength gating device and a control computer. The invention also discloses a method for generating ultra-wideband spectrum laser by using the laser treatment device. The invention further discloses application of the laser treatment device or method in generation of laser with specific wavelength distribution, spectral width, pulse width and / or power requirements, cornea cutting and postoperative recovery, eye crystalline lens cutting, tattooing and stabbing cleaning and postoperative recovery.

The application discloses a multi-period DBR super-radiation light-emitting diode structure with an ultra-wide spectrum width, wherein the upper surface of a P face electrode is divided into four areas, which are a light-emitting end ridge, an active multi-mode interference device, a plurality of non-light-emitting end ridges, a plurality of ridges with different period DBRs and an optical absorption area. The application effectively clamps the gain center wavelength through the multi-DBR structure, so that the center wavelength of the light emitted by the device is different, and then the problem that the spectrum is narrowed due to the fact that the photons close to the center gain wavelength are amplified more and the photons far away from the center gain wavelength are amplified less when the current is increased is effectively suppressed, so that the spectrum width of the device is effectively widened. The tilted ridge structure is adopted, the wide-spectrum antireflection film with a reflectivity less than 2% is deposited on the front and rear cavity surfaces, and the optical absorption area is formed on the non-light-emitting end of the device, so that the F-P oscillation is effectively suppressed through the above three methods, and the emitted light is ensured to be super-radiation light.

A method includes identifying a channel parameter and distance for a new spectrum channel to be launched in an optical band in a fiber broadband network, wherein the optical band comprises a plurality of existing spectrum channels, calculating a spectral width for the new spectrum channel, based at least in part on the channel parameter and the distance, determining that a contiguous slice of the optical band is not available to support the spectral width, identifying a set of candidate channels of the plurality of existing spectrum channels, wherein each candidate channel is a standby channel for a main channel and wherein a predicted network traffic delay associated with a movement of each candidate channel is less than a threshold delay, and marking a subset of candidate channels for movement within the optical band, where a cumulative spectral width of the subset is at least equal to the spectral width.

The invention discloses a wavelength and pulse width dual-adjustment optical fiber seed laser for nonlinear microscopic imaging, which comprises a full polarization-maintaining linear cavity, the full polarization-maintaining linear cavity further comprises a reflection type semiconductor saturable absorber mirror (1), an optical fiber coupler (2), a wavelength division multiplexer (3), a 980 nm pumping laser diode (4), a polarization-maintaining gain optical fiber (5), a variable-focus collimator (6), a transmission diffraction grating (7) and an electric control galvanometer (8). All the devices form the full polarization-maintaining linear cavity between the reflection type semiconductor saturable absorber mirror (1) and the electric control galvanometer (8). The output wavelength of the seed light is tuned within the range of 1010-1090 nm by controlling the angle of the electric control galvanometer (8), the spectral width is tuned within the range of 0.1-5 nm by controlling the variable-focus collimator (6), and then the pulse time domain width is tunable within 2-50 ps. According to the invention, an ideal excitation light source can be provided in a nonlinear imaging system.

This invention discloses a device for real-time analysis of multidimensional information of spatiotemporally mode-locked pulses using an all-fiber structure, belonging to the field of ultrafast optics technology. It includes an all-fiber spatiotemporally mode-locked laser platform, a raw pulse beam profile measurement module, an optical circulator, a sub-pulse beam profile measurement module, and a dispersive Fourier transform and real-time spectral information detection module. Based on the generalized multimode nonlinear Schrödinger equation, this invention constructs a theoretical model of the spatiotemporally mode-locked laser, explores the multidimensional parameter coupling mechanism during spatiotemporal mode-locking, clarifies the mapping relationship between modes and frequencies, and provides a theoretical basis and method for high-precision mode differentiation and multidimensional real-time information extraction. This invention aims to rationally design the parameters of each fiber grating according to the spectral width and temporal interval of the spatiotemporally mode-locked pulse, reflecting more sub-pulses while ensuring that the pulse temporal domains do not overlap, achieving high-precision spatial mode resolution, and maximizing pulse broadening to obtain high-resolution real-time spectral information.

The invention discloses a method, a system and a laser for adaptively suppressing stimulated Brillouin scattering. The method comprises the following steps: performing phase modulation on target laser based on a first phase modulation signal in a signal set to obtain optimized laser; a return light signal of the optimized laser in the current system state is obtained, the value of a first objective function of the first phase modulation signal is calculated, the value of the first objective function is related to a first preset optimization dimension, and the first preset optimization dimension is an optimized SBS suppression effect, or the value of the first objective function is related to a second preset optimization dimension. The first preset optimization dimension comprises optimization of the SBS inhibition effect and optimization of the broadened estimated spectral width; based on a preset optimization algorithm, taking a first preset optimization dimension as a target, and according to a value of a first target function corresponding to each phase modulation signal in the signal set, iteratively adjusting a waveform parameter of the phase modulation signal so as to update the signal set; and after iterative optimization is finished, outputting a waveform parameter which enables the first preset optimization dimension to be optimal as an optimal solution. Therefore, dynamic optimization is realized, and the SBS suppression efficiency is improved.

Provided are a method and apparatus for establishing a subcarrier connection, a storage medium, and an electronic apparatus. The method includes: determining following configuration parameters according to a first bit rate required by a client signal: a spectrum central frequency of an OTSi at a transmitting end, a spectral width occupied by the OTSi at the transmitting end, a spectrum central frequency of the OTSi at a receiving end, a spectral width occupied by the OTSi at the receiving end, a bit rate that each subcarrier corresponding to the OTSi is allowed to provide, and application code for the subcarrier; and establishing the subcarrier connection according to the configuration parameters.

This invention relates to the field of geotechnical engineering disaster monitoring and safety early warning technology, and particularly to a method for early warning of locked-in rock slope instability based on multifractal parameters and CRITIC weighting. The steps are as follows: signals are acquired and a time series is constructed; multifractal analysis is performed on the time series to obtain the spectral width Δα and the spectral width difference Δα0, followed by dimensionless standardization; the CRITIC method is used to objectively weight the multifractal characteristic parameters; and a composite early warning index λ is constructed. t According to the composite early warning indicator λ t The invention provides a method for early warning of locked-in rock slope instability based on multifractal parameters and CRITIC weighting. This method extracts characteristic parameters reflecting damage nonuniformity and critical states by performing multifractal analysis on acoustic emission signals inside the rock slope and external optical strain signals. It then uses the CRITIC objective weighting method to fuse multiple indicators, constructing a composite early warning index to achieve graded early warning of locked-in rock slope instability.