165 results about "Mode matching" patented technology

The invention relates to the technical field of electrical fault diagnosis, and discloses an electrical system fault diagnosis method based on multiple parameters. According to the method, multi-dimensional operation parameters of an electrical system are collected, wherein the multi-dimensional operation parameters comprise voltage waveform data, current waveform data and temperature distribution data; time-frequency conjoint analysis is carried out on the multi-dimensional operation parameters, and multi-scale electrical features are extracted and comprise steady-state feature components and transient feature components; based on a historical fault case library, performing mode matching on the multi-scale electrical characteristics to generate an initial fault type set; performing confidence evaluation on the fault types in the initial fault type set by using a dynamic weight distribution algorithm, and screening out high-confidence fault types; and according to the high-confidence fault type, a fault evolution path model is constructed, and the fault evolution path model is used for describing a time sequence of fault features.

The invention relates to the field of hydrogen leakage and combustion detection, and discloses a hydrogen leakage and combustion identification method, which comprises the following steps: S1, collecting multiple types of detection signals from acoustic, electrochemical and infrared thermal image sensors; s2, preprocessing the collected signals to generate a multi-dimensional feature space; s3, constructing a topological structure in the multi-dimensional feature space, extracting topological features, and generating topological descriptors; s4, analyzing the time dynamic change of the topology descriptor based on a Markov chain model; s5, calculating the topological similarity between the real-time signal and the known mode, and carrying out mode matching; and S6, calculating a signal state through a comprehensive decision function, judging whether a hydrogen leakage or combustion event exists, and triggering a corresponding alarm. According to the invention, through multi-sensor cooperative monitoring, signal preprocessing, topological structure analysis and dynamic modeling, high-precision real-time monitoring and reliable alarm of hydrogen leakage and combustion are realized, and the system has the advantages of high sensitivity, low missing report rate and rapid response.

The invention discloses a cross-channel marketing automation method and system based on real-time behavior triggering. The method comprises the following steps: capturing a user behavior event flow in real time through a front-end acquisition unit; performing real-time mode matching on the event stream by utilizing a complex event processing engine, and generating a marketing trigger signal when a preset rule is matched; dynamically selecting an optimal channel for the user based on a real-time scoring model in response to the signal; the marketing content is sent to the selected channel through the unified execution module; and finally, tracking user feedback and updating model parameters and user preferences in real time to form closed-loop optimization. The corresponding system comprises a front-end data acquisition module, a streaming event processing module, a real-time intelligent decision-making module, a multi-channel execution module and a closed-loop optimization module which are used for implementing the steps. According to the method, millisecond-level intention perception, cost and experience optimal channel intelligent decision and data-driven adaptive optimization closed loop are realized, and the problems of delayed response, extensive channel and lack of self-adaption of traditional marketing are solved.

The invention relates to the technical field of signal processing, and provides an intelligent sensing device electromagnetic interference suppression method and system based on AI identification, and the method comprises the steps: obtaining a multi-source electromagnetic signal set of a target intelligent sensing device in a preset monitoring period, and carrying out the electromagnetic interference feature extraction processing of the multi-source electromagnetic signal set, performing interference mode matching processing on the electromagnetic interference characteristic set based on a preset interference suppression model to generate an electromagnetic interference suppression strategy of the intelligent sensing equipment; the electromagnetic interference suppression strategy comprises a frequency band adjustment direction corresponding to an interference frequency band distribution characteristic, a signal gain compensation direction corresponding to an interference intensity fluctuation characteristic and an anti-interference filtering direction corresponding to an interference source correlation characteristic; and performing interference suppression operation on a signal acquisition module of the intelligent sensing equipment according to the electromagnetic interference suppression strategy so as to reduce the electromagnetic signal distortion rate of the intelligent sensing equipment.

The invention belongs to the technical field of optoelectronic devices, and provides a laser gyroscope frequency stabilization system and a frequency stabilization method thereof.The laser gyroscope frequency stabilization system comprises a large laser gyroscope to be subjected to frequency stabilization, an electro-optical modulator, an adjusting light path, a signal generator, a mode matching mirror set, a PID regulator, a frequency mixer, a photoelectric detector, an ultra-stable cavity, a low-pass filter, a computer and a data acquisition card; and a square transmission light path is arranged in the ultra-stable cavity. According to the invention, the problem of insufficient isolation caused by an optical isolator consisting of a polarization splitting prism and a 1 / 4 wave plate is effectively avoided, the influence of an optical feedback effect is reduced, and the optical isolator is better adapted to the field of high-precision measurement related to a large laser gyroscope.

The application discloses a double-resonance atomic clock ultra-miniature substrate integrated waveguide chamber, comprising: a substrate integrated waveguide annular gap cavity, the substrate integrated waveguide annular gap cavity is formed by longitudinal stacking of a plurality of longitudinal slit substrate integrated waveguides, the longitudinal slit substrate integrated waveguide comprises a metalized through hole and a metal microstrip line, and the longitudinal slit substrate integrated waveguide is provided with a longitudinal slit; a MEMS atomic gas chamber; a mode matching excitation structure for exciting a microwave magnetic field to the substrate integrated waveguide annular gap cavity; and an electromagnetic shielding and heating assembly arranged outside the substrate integrated waveguide annular gap cavity. The application can effectively solve the key problem that the resonant performance of a printed miniature annular gap cavity is extremely sensitive to the size change of subwavelength structure parameters, increase the processing tolerance of the ultra-miniature integrated chamber, reduce the processing difficulty and manufacturing cost of high-precision PCB through holes, and improve product yield.

The invention discloses a broadband high-isolation on-chip small-size power divider applied to 5G, and the power divider comprises two branches, and the first branch and the second branch are respectively provided with a series capacitor, an on-chip grounding spiral inductor, a transmission line, an isolation capacitor, an isolation inductor and an isolation resistor. The isolation capacitor, the isolation inductor and the isolation resistor are electrically connected between the first branch circuit and the second branch circuit, and the transmission line is less than a quarter wavelength. The spiral inductors on the ground lugs connected in parallel are used for improving even mode matching of the power divider, and the isolation capacitors and the isolation resistors are used for improving odd mode matching of the power divider. By adopting the transmission line with the wavelength smaller than 1 / 4, the power divider provided by the invention effectively reduces the circuit size and can realize two-path power synthesis. The technical problem that a power divider in the prior art is difficult to adapt to the high integration level of a 5G radio frequency system can be solved, and the provided power divider also has the characteristics of wide band and high isolation.

The invention relates to an intelligent identification and conversion control method for a charging interface of a multi-standard charging pile in the field of new energy automobiles, and the method comprises the steps: carrying out the mode matching analysis of interface physical feature data and communication signal feature data, and obtaining a preliminary classification result of the type of a charging interface device; according to the loading result of the communication configuration parameters, obtaining a confirmation feedback signal of successful protocol switching; judging whether the load demand data conforms to a rated output power range of a charging interface device or not; according to the authorization instruction, current intensity data including a peak value and an average level and voltage level data including a fluctuation amplitude in the charging process are monitored in real time; if the current intensity data or the voltage level data exceed a preset safety threshold value, power supply connection is disconnected, and a circuit path is cut off; and generating a power-off record log containing abnormal fluctuation data and a power-off moment according to a result of disconnecting the power supply connection.

The invention relates to the technical field of measurement signal transmission, and discloses a measurement signal real-time transmission system in air-ground cooperative localization, which is characterized in that an environment signal fingerprint spectrum and a modulation depth spectrum representing environment modulation intensity are generated offline, and in a real-time stage, a mobile terminal sends a detection signal and attitude data of the mobile terminal; and the positioning correlator performs self-adaptive pre-normalization on the physical characteristics of the received signal according to the attitude data and the modulation depth map, and performs mode matching with the fingerprint map to determine the position. According to the invention, the superposition influence of the attitude change of the mobile terminal and the environmental reflection on the signal can be effectively separated; the problem that different positioning results are generated at the same position due to different flight attitudes is avoided, the system has the capabilities of signal time sequence verification and atlas timeliness diagnosis, and the measurement reliability and the system adaptability in a complex real environment are improved.

The invention belongs to the field of solid lasers, and particularly relates to a laser for realizing high-power pump beam quality enhancement based on multi-stack heat transfer, which comprises a pump module, a pump shaping coupling module, a multi-stack crystal, a cube-corner prism, an output mirror and a cooling device. And the multi-laminated crystal adopts a high-thermal-conductivity diamond film, so that transverse rapid diffusion of heat is realized, local heat accumulation and temperature rise are relieved, wavefront distortion and a thermal lens effect caused by thermally induced refractive index change are reduced, and the stability of a laser mode is improved. The cube-corner prism is used as a resonant cavity mirror surface, can automatically compensate angle deviation, optimizes mode matching in the cavity, has a synergistic effect with a zigzag total internal reflection path in the crystal, further balances a heat affected zone, improves light field distribution, and remarkably improves light beam uniformity, stability and TEM00 mode quality. The structure is high in adaptability, is suitable for various wavelengths, pumping modes and thermal loads, and assists the laser to realize miniaturized, high-integration and high-performance output.

The invention relates to the technical field of intelligent transportation, and discloses a mine intelligent transportation method and system. The method comprises the following steps: performing time sequence filtering and gradient denoising on mine transportation node temperature data acquired by a thermal imaging camera to obtain a temperature characteristic matrix; identifying transportation abnormal information based on the temperature characteristic matrix; executing temperature mode matching according to the transportation abnormal information, and generating a transportation operation instruction set; performing mine channel temperature safety path planning by taking the transportation operation instruction set as a constraint condition to obtain a transportation execution scheme; after the specific position of a mine worker is positioned in real time through a thermal imaging camera, a transportation execution scheme is converted into a standardized voice instruction, the standardized voice instruction is pushed to the corresponding worker through an interphone network partition, and scheduling feedback data containing instruction receiving confirmation and execution progress are obtained in real time. According to the invention, operators are accurately positioned through thermal imaging, and partition pushing is realized in combination with an interphone network, so that the intelligent level and safety of mine transportation are improved.

This invention relates to the field of optical device technology, and proposes an end-face coupler based on the coupling of optical fiber and lithium niobate waveguide, comprising a substrate, an insulating layer, a first planar layer, a first waveguide core layer, and a second waveguide core layer. The first waveguide core layer includes a first waveguide and a first tapered waveguide, with one side of the first waveguide connected to one side of the first tapered waveguide, and the widths of the connected sides of the first and second waveguides being the same. The second waveguide core layer includes a second waveguide and a second tapered waveguide, with one side of the second waveguide connected to one side of the second tapered waveguide, and the widths of the connected sides of the second and second waveguides being the same. The first and second tapered waveguides coincide with each other in opposite directions; the side of the second waveguide away from the second tapered waveguide is mode-matched to an external optical fiber. The first planar layer and the first waveguide core layer are made of thin-film lithium niobate material, and the second waveguide core layer is a material with a refractive index higher than that of the insulating layer or a material with a periodic distribution of high and low refractive indices.

The invention discloses a heterogeneous hybrid integration method of a planar optical waveguide device, and relates to the technical field of integrated silicon photonics, the method is used for heterogeneous hybrid integration of PLC chips with large waveguide feature size difference in different material systems, and the method comprises the following steps: firstly, carrying out large-angle grinding on a light emitting end of a front-end chip to enable a waveguide to form a reflection angle; a grating coupler is arranged on a front-end chip, a device surface of the front-end chip is opposite to a device surface of a rear-end chip, so that emergent light of the front-end chip can be reflected to the device surface of the rear-end chip and is aligned with the grating coupler on the device surface of the rear-end chip, and finally the two aligned chips are packaged to realize optical interconnection of the two chips. According to the technical scheme, when heterogeneous integration is carried out, emergent light of the front-end chip can be directly aligned to the grating coupler of the rear-end chip, the height difference problem of the two chips does not need to be considered, the problems that in an existing end face coupling technology, the chip height difference is sensitive, and coupling modes are difficult to match are solved, and the coupling efficiency is improved. And the integration level of the discrete device optical network system is effectively improved.

A laser chip provided in the present invention. The laser chip comprises a first electrode layer, an active layer, a waveguide layer, and a second electrode layer, respectively. In an optical field propagation direction, the waveguide layer comprises a waveguide layer section I, a waveguide layer section II, and a waveguide layer section III. The waveguide layer section I uses a shallow-etched ridge waveguide structure, and the waveguide layer section III uses a deep-etched ridge waveguide structure. In order to improve the coupling efficiency between the waveguide layer section I and the waveguide layer section III, the waveguide layer section II is provided. In the optical field propagation direction, the waveguide layer section II is divided into a first connecting portion and a second connecting portion, the first connecting portion uses a shallow-etched ridge waveguide structure, and the second connecting portion uses a deep-etched ridge waveguide structure to realize continuity in etching depth. In addition, the second connecting portion comprises a first tapered section and a second tapered section, and the side walls, close to the ridge structure, in the first tapered section and the second tapered section progressively converge toward the ridge structure, achieving optical field mode matching, and improving the coupling efficiency of the laser chip.

The invention provides a gas concentration measurement method based on a wavelength correction open ring-down cavity absorption spectrum. Tuned continuous laser is incident into the ring-down cavity to realize mode matching with the optical ring-down cavity, the acquisition module synchronously obtains a laser control signal and a transmission light intensity signal, the matched wavelength is corrected according to the corresponding relation between the current for controlling laser wavelength tuning and the laser wavelength, and accurate absorption spectrum abscissa data is obtained; the method comprises the following steps: carrying out linear processing on an exponential decay signal generated by each mode matching, calculating by using discrete Fourier transform to obtain initial light intensity and an initial offset value, carrying out iterative solution on a linear model to obtain exponential decay time, obtaining ordinate data of an absorption spectrum, and fitting and extracting the gas concentration by using the absorption spectrum. According to the method, the ring-down signal linearization model is iteratively solved through dynamic correction of the mode matching wavelength of the ring-down cavity, so that the influence of noise on the concentration measurement precision is reduced, and the method has a wide application prospect in the field of trace gas concentration measurement.

The invention provides a dual-circularly-polarized feed source assembly and a feed source system. The dual-circularly-polarized feed source assembly comprises four identical horns, a dual-polarized four-path power division and synthesis network and a T-shaped waveguide circular polarizer which are cascaded. The inner wall of the horn adopts an exponential curve structure, the dual-polarization four-path power division and synthesis network comprises a common input waveguide, a frustum mode matching waveguide cavity and four output waveguides, the T-shaped waveguide circular polarizer comprises a stepped gradient waveguide and a rectangular waveguide, the rectangular waveguide and the stepped gradient waveguide are arranged in a T shape, and the rectangular waveguide and the stepped gradient waveguide are arranged in a T shape. The plane where the wide side of the rectangular waveguide is located has a 30-degree rotation angle relative to the propagation cross section of the tapered waveguide. Compact transformation from linear polarization to circular polarization can be realized through T-shaped butt joint of the stepped gradient waveguide and the rectangular waveguide. The dual-circular polarization feed source assembly has good broadband circular polarization performance.

The present application discloses a method for heterogeneous hybrid integration of planar optical waveguide devices, relating to the field of integrated silicon photonics technology. The method is used for heterogeneous hybrid integration of PLC chips with greatly different waveguide characteristic dimensions in different material systems. The method first grinds the light-emitting end of the front-end chip at a large angle to form a reflection angle for the waveguide. The device surface of the front-end chip is then arranged relative to the device surface of the back-end chip so that the light emitted by the front-end chip can be reflected to the device surface of the back-end chip and aligned with the grating coupler on the device surface of the back-end chip. Finally, the aligned two chips are packaged to achieve optical interconnection between the two chips. When performing heterogeneous integration, the technical solution of the present application can directly align the light emitted by the front-end chip to the grating coupler of the back-end chip without considering the height difference between the two chips. This solves the problem of the existing end-face coupling technology being sensitive to the chip height difference and difficult coupling mode matching, and effectively improves the integration level of the discrete device optical network system.

The invention discloses a fluid filling pipeline guided wave modal tracking method based on an optimal transmission distance. The method comprises the following steps: firstly, calculating a characteristic solution by using a semi-analytical finite element method; secondly, introducing an optimal transmission distance (EMD) in an optimal transmission theory as modal similarity measurement, measuring modal similarity by calculating the minimum physical work of kinetic energy distribution rearrangement, and combining a section geometric geodesic distance to enhance physical interpretability; meanwhile, a continuous stabilization strategy based on wavenumber prediction is introduced to suppress mismatching; and finally, realizing global optimal modal matching by using a Hungary algorithm. According to the method, modal exchange errors can be effectively eliminated, tracking robustness is kept in a complex frequency dispersion area, and meanwhile, visual graphic interpretation of modal evolution can be provided.

The invention provides a laser chip and a preparation method thereof. The laser chip comprises a first electrode layer, an active layer, a waveguide layer and a second electrode layer. The waveguide layer comprises a waveguide layer first partition, a waveguide layer second partition and a waveguide layer third partition in the optical field transmission direction. The first subarea of the waveguide layer adopts a shallow etching ridge waveguide structure, and the third subarea of the waveguide layer adopts a deep etching ridge waveguide structure. In order to improve the coupling efficiency between the first waveguide layer partition and the third waveguide layer partition, a second waveguide layer partition is arranged. And the second subarea of the waveguide layer is divided into a first connecting part and a second connecting part along the transmission direction of the light field, the first connecting part adopts a shallow etching ridge waveguide structure, the second connecting part adopts a deep etching ridge waveguide structure, and the continuity of the etching depth is realized. Meanwhile, the second connecting part comprises a first gradual change part and a second gradual change part, and the side walls, close to the ridge structure, of the first gradual change part and the second gradual change part gradually approach the ridge structure, so that light field mode matching is realized, and the coupling efficiency of the laser chip is improved.

The utility model belongs to the technical field of optical feedback cavity enhanced laser absorption spectrum, and particularly relates to a dynamic phase pneumatic control system based on optical feedback cavity enhanced laser spectrum. In order to provide a dynamic phase adjustment pneumatic control system which does not influence light path collimation, a Fabry-Perot (F-P) cavity is adopted, a distributed feedback type diode laser is used as a light source, the laser and the F-P cavity are subjected to mode matching through a matching lens, a feedback phase is controlled through an adjusting element, and the optical path collimation is not influenced. The incident power and the feedback rate are controlled through the lambda / 2 wave plate, the polarization splitting prism and the lambda / 4 wave plate, then the laser is coupled to enter the F-P cavity and finally is driven into the photoelectric detector through the focusing lens, and the amplitude of the transmitted laser signal is detected.

The invention belongs to the technical field of integrated optical devices, and discloses a compact, high-efficiency and large-bandwidth thin-film lithium niobate end face coupler for large die spots, which comprises a substrate and an insulating layer, the single-layer back taper film lithium niobate waveguide layer, the first double-layer back taper film lithium niobate waveguide layer and the second double-layer back taper film lithium niobate waveguide layer are arranged on the insulating layer; the low-refractive-index waveguide layer is arranged in front of the thin-film lithium niobate waveguide, and the thin-film lithium niobate waveguide is covered with the three-dimensional tapering low-refractive-index waveguide wrapping layer. According to the invention, the coupling efficiency and bandwidth are improved by optimizing the low-refractive-index waveguide layer and matching with the mode of a laser chip large spot; the optical mode is efficiently and compactly coupled to the second double-layer inverted-cone waveguide layer by means of the single-layer and double-layer inverted-cone thin film lithium niobate waveguide layers in cooperation with the three-dimensional tapering low-refractive-index waveguide cladding layer and the transition cladding layer.

The present invention relates to the technical field of MEMS gyroscopes, and in particular to a mode-matching MEMS gyroscope temperature self-compensation control system and method, the system comprising: a driving mode control subsystem for closed-loop control of the phase and amplitude of the MEMS gyroscope driving mode; a detection mode control subsystem for closed-loop control of the bandpass filter gain of the MEMS gyroscope detection mode, and matching the center frequency of the bandpass filter with the detection mode resonant frequency; wherein the driving mode control subsystem and the detection mode control subsystem are force-coupled via the Coriolis effect. The present invention adjusts the gain of the bandpass filter based on the real-time change of the detection mode quality factor, and matches the center frequency of the bandpass filter with the resonant frequency of the detection mode, thereby achieving the suppression and self-compensation of the gyroscope temperature drift.

The invention relates to the technical field of tunnel construction intelligent control, and discloses a tunnel lining construction intelligent trolley and a control system thereof. The system determines a state change time point through event listening, thereby intercepting multi-source sensor data and extracting features. The pattern matching module generates a quality difference measure by comparing a criterion with an abnormal pattern. A causal analysis framework with operation frequency as a regulation variable is innovatively introduced, the influence weight of each sensor data stream on the quality is dynamically evaluated, and key quality factors are accurately identified. And performing partition merging on the optimized feature set based on the construction waveform sequential relationship, and generating a control instruction by adopting an attention mechanism. According to the scheme, conversion from static threshold judgment to dynamic causal inference is achieved, self-adaptive control is achieved through sequential context understanding, and the quality diagnosis accuracy and the adaptability of the system to complex working conditions are improved.

The invention belongs to the technical field of laser frequency stabilization, and discloses an ultra-stable cavity with an optical fiber as a cavity, which comprises an optical fiber cavity component, the optical fiber cavity component comprises an optical fiber, the two ends of the optical fiber are plated with high-reflection films, and the two ends of the optical fiber in the length direction are provided with optical fiber connecting pieces. The ultra-stable cavity provided by the invention adopts the optical fiber, uses the optical fiber optical path, does not depend on vacuum, effectively reduces the volume of the ultra-stable cavity, can get rid of the dependence of a PDH frequency stabilization system on the polarization characteristic of the optical path, does not need to carry out complex cavity-mode coupling, avoids tedious mode matching and optical path adjustment, and is simple and convenient to operate.

The invention relates to the field of signal frequency detection in microwave photonics, and discloses a broadband instantaneous frequency measurement receiving system based on Brillouin spectrum compression, which utilizes a dual-tone pump optical carrier signal carried on an intensity modulator and an optical filter to generate a single Brillouin pump source regulated and controlled by unknown radio frequency. A stimulated Brillouin structure narrowed by an optical fiber ring cavity and a single-pumping reference source subjected to phase shift beat frequency, a signal in a 45GHz range can be compressed to a bandwidth of 2.5 MHz, and meanwhile, an original signal can be subjected to optical domain down-conversion processing by a reference source signal, so that a low-frequency signal easy to process electronically is obtained; besides, a double-fiber annular cavity design is adopted, the line width of the Brillouin resonant laser is further compressed through mode matching of interference of light waves in the cavity, test precision reduction caused by frequency spectrum compression is made up, the resolution ratio can reach + / -2.2 MHz, and finally the Brillouin broadband instantaneous frequency measurement receiving technology is achieved.

The invention discloses a bidirectional amplifier structure, a front-end system, a chip array element and a phased array system. The bidirectional amplifier structure comprises a differential mode signal amplification path; a common mode signal amplification path; the four-branch waveguide joint comprises a common-mode amplification interface, two differential-mode amplification interfaces and two antenna interfaces, the differential-mode amplification interfaces are in one-to-one correspondence with the antenna interfaces, the differential-mode amplification interfaces are connected with the differential-mode signal amplification path, and the common-mode amplification interface is connected with the common-mode signal amplification path; the amplification stage comprises a differential amplification circuit and a common mode amplification circuit; and the matching stage comprises a differential mode matching structure and a common mode matching structure, the differential mode matching structure is connected with the differential amplification circuit, and the common mode matching structure is connected with the common mode amplification circuit. According to the structure of the bidirectional amplifier, the working mode of simultaneous working or time-sharing working is realized by utilizing the characteristics of a signal differential mode and a common mode, and the bidirectional amplifier has higher working efficiency, higher circuit multiplexing rate and higher integration level. The invention relates to the technical field of microwave communication.

The invention relates to a power line communication transmission method, device and system, and the method comprises the steps: firstly obtaining an MIMO channel matrix of a target subcarrier in a power line communication system, then determining a quality evaluation parameter of the target subcarrier according to the channel matrix of the target subcarrier, and then determining a mode matching threshold according to the quality evaluation parameter and the mode matching threshold. And determining a diversity multiplexing mode of the target subcarrier, and finally controlling a sending end to carry out subcarrier mapping and signal transmission processing on the target subcarrier according to the diversity multiplexing mode of the target subcarrier. Namely, by dynamically evaluating the subcarrier quality and adjusting the diversity multiplexing mode in real time, the problem that the prior art cannot adapt to the rapid change of the power line channel is solved, and the method has the advantage of improving the transmission reliability and the rate adaptability of the power line communication system in the dynamic channel environment.

The invention discloses a D-type concave mirror multi-pass hundred-femtosecond laser pulse compression system and method, and belongs to the technical field of ultrafast laser, and the system comprises a mode matching module which focuses a light beam into a cavity of a spectrum broadening module, the spectrum broadening module and a chirp compensation module. The spectrum broadening module comprises a cavity filled with inert gas, a D-shaped concave mirror is fixed at each of the two ends in the cavity, the two concave mirrors are oppositely arranged and are used for realizing multi-pass focusing of light beams, and reflectors for leading the light beams into or out of the D-shaped concave mirrors are arranged at the straight edges of the two concave mirrors; inert gas is used as a nonlinear broadening medium, femtosecond laser pulses are spread back and forth between the two D-shaped concave mirrors and are focused, a self-phase modulation effect is generated through the inert gas argon, and the spectrum is broadened. The pulse energy and quality can be improved while wide spectrum broadening is achieved, and shorter femtosecond pulses are obtained.

This application relates to the field of charging pile testing, and in particular to a method and system for detecting abnormal states of charging piles based on harmonic fingerprints. The method includes: acquiring a broadband harmonic raw dataset from the output end of the charging pile during charging; based on the broadband harmonic raw dataset, extracting and structurally encapsulating full-band harmonic components categorized into three major component types within the charging pile to generate a component-level harmonic feature fingerprint set; based on the component-level harmonic feature fingerprint set, performing fault harmonic mode matching and component category determination for the current abnormal charging pile to generate a fault component category information set; based on the fault component category information set, constructing fault component location confirmation and production responsibility traceability logic, generating and outputting a fault diagnosis and traceability report set. This application, in the process of detecting abnormal states in charging piles, can locate the root cause of the fault, guide efficient maintenance, and drive the optimization of component design and procurement quality.

A device for attaching at least one optical fiber to a chip includes at least one nanowaveguide disposed on a substrate of a chip to be attached to an at least one off-chip fiber respectively. At least one oxide taper mode converter is disposed around a nanowaveguide end and in optical communication with and modally coupled to each of the at least one nanowaveguide respectively, and adapted such that each corresponding fiber of at least one off-chip fiber corresponds to a cleaved fiber end each cleaved fiber end to be fused to each oxide taper mode converter respectively to optically couple and mode match each cleaved fiber end to each of the nanowaveguide ends of each of the at least one nanowaveguide via the oxide taper mode converter by a modal coupling. A method for attaching at least one optical fiber to a chip is also described.