63 results about "Spectral width" patented technology

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.

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 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.

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 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.

In the present invention, light to be measured is output from a coherence-wavelength-swept light source, is split into signal light and reference light by a first optical coupler which are then recombined by a second optical coupler and then output as a first interference signal, a second interference signal, and a third interference signal having phases different by 120°, and each of the signals is detected by a photodetector. A correction matrix in which factors that vary over time is calculated, the factors relating to amplitudes due to the first optical coupler and the second optical coupler, the quantum efficiency of the photodetector, and phase due to the second optical coupler. The phase difference between the signal light and the reference light is calculated by using the first interference signal, the second interference signal, the third interference signal, and the correction matrix. The spectral width of light is calculated by using the phase difference, and the coherence-distance of light is calculated by using the spectral width.

The invention provides a modulation identification method for radar communication integration, and belongs to the technical field of signal modulation identification. The method comprises the following steps: performing preprocessing and phase space adaptive reconstruction on a signal, extracting the spectral width, asymmetry degree and spectral peak value of a multi-fractal singular spectrum of the signal, and forming a robust nonlinear feature vector; constructing a meta-learning model comprising a shared feature embedding backbone network, a task awareness routing network and a modulation recognition classifier; thirdly, training the model by adopting a double-layer optimization strategy to enable the model to obtain cross-task rapid adaptive capacity; in the face of a new task, a very few samples are used for rapidly driving a routing network to adjust a feature path and finely adjust a classifier, and accurate recognition of unknown signals is achieved. According to the method, the problems of feature distortion, dependence on a large amount of labeled data and poor generalization ability of a traditional method under a low signal-to-noise ratio are solved, and the recognition robustness, the small sample adaptive ability and the real-time processing efficiency in a dynamic complex electromagnetic environment are remarkably improved.

The present application relates to radar wind field data related technical field, specifically including an airport wake vortex radar wind field data enhancement method based on spectral width anomaly detection, the method comprises: based on the initial error matrix, the spatial error component of each detection partition, configure dynamic data enhancement matrix, under the constraint of wake vortex dissipation time iteration optimization enhancement parameter, carry out the enhancement decision of wind field data deviation. The technical problems of unable to accurately decompose the spatial error component of horizontal wind direction angle and vertical wind shear, easy to confuse the action law of different interference sources, and difficult to effectively improve the signal-to-noise ratio of wind field data are solved, the technical effects of introducing the spatial correlation mapping of the detection partition wind field direction vector and the wake vortex influence area, optimizing the enhancement coefficient, accurately splitting the horizontal and vertical direction spatial error component, extracting the environmental disturbance enhancement factor, efficiently decoupling the atmospheric turbulence, electromagnetic interference and equipment noise, improving the space-time consistency of wind field data, and reducing the wake vortex early warning false alarm rate are realized.

This invention relates to the field of semiconductor laser technology, and more particularly to a semiconductor laser with switchable spectral width. The laser includes a mesa and a ridge waveguide located in the middle of the mesa. From bottom to top, the mesa includes an N-type electrode layer, a substrate layer, an N-type cladding layer, an N-type waveguide layer, an active layer, and a P-type waveguide layer. The ridge waveguide is located at the upper middle part of the P-type waveguide layer and, from bottom to top, includes a P-type cladding layer, a P-type capping layer, and a P-type electrode. The two sides of the ridge waveguide are insulating layers, and a periodic electrode is included on the insulating layer on one side of the ridge waveguide. When a current is applied to the periodic electrode, frequency selectivity can be achieved by modulating the optical field distributed within the periodic electrode region, thus narrowing the laser spectral width. When no current is applied to the periodic electrode, the laser oscillates at the front and rear cavity surfaces and exhibits broadband lasing characteristics. This invention also provides a method for fabricating a semiconductor laser with switchable spectral width.

A system, apparatus and method directed to detecting damage to an optical fiber. The optical fiber includes core fibers including a plurality of sensors configured to (i) reflect a light signal based on received incident light, and (ii) change a characteristic of the reflected light signal based on experienced strain. The system can include a console having memory storing logic that, when executed, causes operations of providing receiving reflected light signals of different spectral widths of the broadband incident light by one or more of the plurality of sensors, processing the reflected light signals to detect fluctuations of a portion of the optical fiber, and determining a location of the portion of the optical fiber or a defect affecting a vessel in which the portion is disposed based on the detected fluctuations. The portion may be a distal tip of the optical fiber.

This invention provides a continuous U-band high-gain Raman fiber amplification module. It utilizes a Raman gain fiber with a dedicated gain peak at a 13 THz frequency shift, coupled with a broadband pump source with a 3 dB spectral width of at least 10 nm. A pump signal combiner is used to achieve efficient fusion coupling between the pump light and the U-band signal, ensuring that the broadband pump energy is precisely matched to the amplification requirements of the U-band signal. This achieves efficient high-gain amplification of the U-band signal, filling the amplification capability gap in this band of traditional amplifiers, ensuring the stability and efficiency of the amplification process, and ultimately outputting a high-purity, high-gain U-band laser signal. Compared with traditional Raman methods, this invention's Thraman fiber amplification module has advantages such as simple structure, high gain, and low cost, and has significant practical value and application prospects.

An example system includes a hub transceiver and a plurality of edge transceivers. The hub transceiver is operable to transmit, over a first communications channel, a first message to each of the edge transceivers concurrently, including an indication of available network resources on an optical communications network. The message may be transmitted through amplitude modulation of a plurality of optical subcarriers output from the hub. Each of the edge transceiver is operable to transmit, over a second communications channel, such as a subcarrier having a reduced spectral width and / or power than optical subcarriers carrying user data. The second communications channel carries a respective second message to the hub transceiver including an indication of a respective subset of the available network resources selected by the edge transceiver for use in communicating over the optical communications network. Further, the edge transceiver is operable to receive, from the hub transceiver, a third message acknowledging receipt of a selection and a fourth message confirming an assignment of the selected subset of the available network resources to the edge transceiver.

Measuring the coherence distance of a coherence light source operating in a very high frequency band. [Solution] The light to be measured is output from a coherence wavelength-swept light source, separated into signal light and reference light by a first optical coupler, and combined by a second optical coupler. These are then output as a first interference signal, a second interference signal, and a third interference signal, each with a phase difference of 120°. Each of these is detected by a photodetector. A correction matrix is ​​calculated in which factors related to the amplitude of the first and second optical couplers, the photoelectric efficiency of the photodetector, and the phase of the second optical coupler change over time. The phase difference between the signal light and the reference light is calculated using the first, second, and third interference signals and the correction matrix. The spectral width of the light is calculated using the phase difference, and the coherence distance of the light is calculated using the spectral width.

This invention discloses a meteorological signal spectral moment estimation method based on B-ELM. The method includes the following steps: acquiring meteorological pulse data; converting the meteorological pulse data into a meteorological power spectrum using the average corrected periodogram method; using the meteorological power spectrum as the input of the network training samples and the spectral moments as the output of the network training samples to construct the training samples; randomly setting the parameters of the hidden nodes, determining the number of input layer nodes and the number of output layer nodes, and selecting the activation function; constructing a prediction model based on the B-ELM algorithm to obtain the optimal meteorological signal radial velocity and spectral width prediction model; substituting the training samples, the set number of input layer nodes, and the number of output layer nodes into the obtained optimal meteorological signal radial velocity and spectral width prediction model to obtain the radial velocity and spectral width of the meteorological signal. This method has a fast convergence speed, small error, improves the accuracy of meteorological signal spectral moment estimation, and has low computational complexity, which is beneficial for engineering implementation.

The present application relates to the technical field of stimulated emission devices, and particularly provides a method and system for self-similar evolution of femtosecond pulses in a chip-level waveguide, the method comprising: introducing input femtosecond pulses into an entrance section of a chip waveguide composed of birefringence heterogeneous materials; obtaining an initial pulse with internal space-time correlation; inputting the initial pulse into a distributed parameter dynamic compensation array in a middle section of the chip waveguide to form synchronous dynamic compensation for nonlinearity and dispersion, and obtaining an intermediate pulse with stable spectral width and phase distribution; inputting the intermediate pulse into an output coupler at an end of the waveguide; simultaneously solidifying a pulse time-domain envelope shape determined by dispersion truncation effect; and outputting femtosecond pulses with self-similar characteristics, stable shape and spectrum after processing by the coupler. The system comprises a space-time correlation processing module, a dynamic compensation synchronization module and a coupling processing module. The present application significantly improves controllability and output quality of femtosecond pulse evolution in an integrated waveguide.