1385 results about "Wide band" patented technology

The invention discloses a method for preparing a single-layer tungsten diselenide nanoband based on a space confinement strategy. By changing the flow and the growth time of hydrogen, effective control on the width and the thickness of a nanoband can be realized. The method comprises the following steps: uniformly spraying tungsten trioxide powder to one substrate, then covering the substrate by the other substrate, and forming micro reaction space which is of a 'sandwich'-like structure. Growth of a tungsten diselenide nanoband is carried out by utilizing a constant-pressure chemical vapor deposition method; physicochemical characteristics of a one-dimensional transition metal chalcogenide strongly depend on suspension key types on the edge of the one-dimensional transition metal chalcogenide, metallic properties are displayed by an ultranarrow band, and conversion from the metallic properties to semiconductor properties can be displayed from the edge to the center of a wider band; the tungsten diselenide nanoband is widely applied to micro-nano photoelectric devices due to the special property; industrial production of the tungsten diselenide nanoband can be realized through an experimental method of the invention.

The invention particularly relates to a leakage current testing method, device and system for an intelligent circuit breaker, and relates to the technical field of electrical safety detection. A composite signal generation and injection module; a broadband signal acquisition and conditioning module; and a line fault positioning and impedance analysis module. According to the invention, the composite signal generation module realizes the non-interference isolation injection of a leakage current signal and a high-frequency positioning signal, and guarantees the high fidelity of data through adaptive filtering, multi-channel synchronous sampling and high-precision timing. The line positioning module integrates TDR and a frequency domain impedance method, and through multi-frequency point deviation correction and topology-GIS association, the fault type is accurately identified, and the test and troubleshooting period is significantly shortened.

The invention discloses a distribution line broadband waveform sampling method, and belongs to the technical field of power system monitoring. By collecting quantum vacuum fluctuation noise, temperature, humidity and electromagnetic parameters, a quantum environment coupling entropy model is constructed, an optimal sparse base dictionary is dynamically generated, and a noise entropy break variable is calculated. And when the entropy break variable exceeds a threshold value, triggering sub-Nyquist compressed sampling, otherwise, adopting Nyquist rate sampling to realize dynamic matching of sampling resources and signal complexity. A high-frequency component of a compressed signal is reconstructed by combining an adversarial compressed sensing network with a residual network, a low-frequency component is generated based on an original signal, the distribution consistency of high and low frequency entropies is optimized by using a Wasserstein distance, and finally a three-dimensional waveform matrix containing a timestamp, a frequency bin and quantum entropy confidence is output. The problems of low sampling efficiency, poor sparse representation adaptability, slow noise response, inconsistent reconstruction and the like in a non-stationary signal and complex noise environment are solved, and the precision and energy efficiency of broadband waveform sampling are remarkably improved.

The invention discloses a method and a system for capturing an ultra-wideband navigation signal of a low-orbit satellite, which are used for solving the technical problem that the existing method for capturing the ultra-wideband navigation signal of the low-orbit satellite is easy to cause that the signal cannot be locked, and finally the capturing success rate is low. The method comprises the following steps: acquiring ka-band low-orbit satellite signals and low-orbit satellite pseudo-random noise codes corresponding to a plurality of low-orbit satellite ultra-wideband navigation signals; generating a complex signal and an original intermediate-frequency signal according to a preset sampling rate, preset skipping time and the ka-band low-orbit satellite signal; constructing a pseudo-code spectrum library based on the pseudo-random noise codes of the low-orbit satellites, and outputting the pseudo-code spectrum library; determining a discrete frequency search sequence based on known intermediate frequency parameters of the original intermediate frequency signal, performing matrix construction in combination with the complex signal and the pseudo code spectrum library, and outputting a three-dimensional result matrix; and capturing and judging the ultra-wideband navigation signals of the low-orbit satellites by adopting the three-dimensional result matrix, and determining a plurality of successfully captured ultra-wideband navigation signals of the low-orbit satellites.

The invention provides a grid-connected inverter impedance detection method based on an L-shaped filter, and belongs to the technical field of grid-connected inverter impedance detection. A multi-frequency-point disturbance signal is injected into a preset grid-connected inverter working point, time domain data of inverter side current and common coupling point voltage are collected, fast Fourier transform analysis is carried out on the collected data, amplitude and phase information corresponding to each injection frequency point is extracted, and a frequency domain feature vector matrix is established; and establishing a frequency compensation matrix model to compensate and correct high-frequency band measurement data based on a frequency characteristic attenuation vector, calculating to obtain optimal estimated values of power grid impedance and grid-connected inverter output impedance, performing error analysis and precision verification on an impedance detection result, and outputting a verified impedance parameter value. The technical problem of insufficient power grid impedance detection precision caused by high-frequency band attenuation of the L-shaped filter is solved.

The invention belongs to the technical field of metal crack detection, and discloses a metal microcrack ultrasonic detection method, which comprises the following modules: an ultrahigh frequency composite array probe with a center frequency dynamic adjustable range of 5-50 MHz; the dual-mode excitation and receiving module is used for independently generating a pulse reflection mode excitation signal and a diffraction mode chirp frequency modulation signal; the phase-controlled synthetic aperture dynamic focusing module is used for realizing + / -60-degree deflection and sub-wavelength level focusing of acoustic beams; the nonlinear harmonic enhancement module is used for exciting a crack nonlinear effect by superposing 1-2MHz fundamental waves; and a time-space-frequency three-domain data fusion module. According to the method, signal-to-noise ratio collapse caused by the diffraction effect in a traditional method is overcome, more importantly, the system has low-frequency penetrability and high-frequency resolution at the same time due to 80%-120% of broadband coverage of chirp frequency modulation signals, the diffraction signal gain is increased by 20 dB or above, a near-surface blind area is compressed to be within 0.2 mm, and the system can be applied to the field of radar imaging. And the core pain point of missing detection of the near-surface microcracks of the thin-wall component is solved.

The invention belongs to the technical field of quality detection, and discloses an electrical automation quality detection method and system. The method comprises the steps of collecting original voltage and current signals of a PCC point of a power grid and performing FFT to obtain a background harmonic frequency set and a background harmonic amplitude set; generating an initial frequency grid based on a preset target frequency band, and generating a sparse frequency grid in combination with the background harmonic waves; calculating the estimated signal-to-noise ratio of each candidate frequency, performing ascending sorting to obtain an injection sequence, injecting sinusoidal signals, collecting PCC point voltage response and total current, and calculating a frequency impedance data pair; performing rational function fitting based on the frequency impedance data to obtain a broadband impedance curve; analyzing the curve, extracting quality characteristic parameters, and performing quality judgment according to the parameters; according to the method, the technical problem that the grid-connected stability quality of a single new energy converter cannot be quickly and automatically qualified in a production line offline detection scene in the prior art is effectively solved.

The utility model provides a high-voltage pulse generating device and a test system. The high-voltage pulse generating device comprises a main control unit, a driving circuit, a pulse control circuit with a wide bandgap semiconductor power device, and an output circuit, the first end of the main control unit is coupled with the first end of the driving circuit, the second end of the driving circuit is coupled with the first end of the pulse control circuit, and the second end of the pulse control circuit is coupled with the output circuit; the main control unit is configured to generate two paths of first PWM (Pulse Width Modulation) signals with dead time control; the two paths of first PWM signals are sent to the driving circuit; and the driving circuit is configured to process the first PWM signal and then drive the pulse control circuit, so that the output circuit generates a high-voltage pulse signal. According to the utility model, the structure is simple, the cost can be greatly reduced, the output pulse speed can be flexibly set, and the CMTI test requirements of different isolated gate drivers can be met.

The invention discloses a bifunctional chiral metamaterial surface capable of switching polarization conversion and wave absorption, and belongs to the technical field of electromagnetic metamaterials. The method is used for solving the problem that most existing chiral super-structure surfaces cannot realize dynamic adjustability and quantitative controllability and cannot have dual functions of polarization conversion and wave absorption at the same time. The super-structure surface unit structure is composed of a graphene film layer, a gold-vanadium dioxide resonance layer, a silicon dielectric layer and a bottom-layer continuous gold film. Switching of two functions of polarization conversion and wave absorption is realized by changing the conductivity of vanadium dioxide; polarization conversion and dynamic regulation and control of the wave absorbing efficiency are realized by changing the Fermi level of the graphene; quantitative controllability of polarization conversion and a wave absorbing function is realized by controlling a function weighting function. Besides, the chiral super-structure surface also has the advantages of incident angle robustness, small thickness and small size, has double functions of broadband, and has potential application value in the fields of optical devices, communication equipment, biomedical sensors and the like.

Monitoring object movement comprises attaching an ultra-wide band (UWB) sensor to an object and transmitting, by the UWB sensor in a radar mode, a plurality of UWB pulses. The UWB sensor in the radar mode receives a plurality of reflected UWB pulses and determines over a time a channel response (CIR) based on the plurality of transmitted and reflected UWB pulses. The CIR is indicative of the object movement.

The invention discloses a device and a method for measuring geometric parameters and performance parameters of a sample, the device comprises a white light interference measurement module, a Raman spectrum measurement module and an ellipsometry measurement module, and the white light interference measurement module and the Raman spectrum measurement module adopt a partial common-path design. Common-optical-path measurement of Raman spectrum data and interference fringe images is achieved, the surface appearance and material composition information of the same measurement point position can be obtained at the same time, and in-situ high-precision obtaining of geometric parameters and material composition information in ellipsometry modeling is achieved. The condition of analysis errors caused by inconsistent information carried by different measurement points of the heterogeneous film is avoided, and the precision and the reliability of an ellipsometry measurement result can be greatly improved. According to the method for measuring the geometric parameters and the performance parameters of the film layer on the surface of the wide bandgap semiconductor wafer, the morphological information and the performance parameters of the heterogeneous film can be comprehensively and accurately measured and represented by combining the ellipsometric spectrum, the white light interference, the Raman spectrum and other technologies.

A method of a first ultra-wide band (UWB) device according to an embodiment of the disclosure may comprise exchanging at least one message for downlink time-difference-of-arrival (DL-TDoA) with a second UWB device in a first period, receiving a first message for two-way ranging (TWR) from the second UWB device in a second period for a hybrid UWB session (HUS), and transmitting a second message for the TWR to the second UWB device in a third period for the HUS. A different session ID may be allocated to each of the second period and the third period for the HUS.

The invention provides an ultrasonic detection method for internal defects of an insulating part of a power system based on a piezoelectric ultrasonic transducer, and belongs to the technical field of insulating part detection. After wavelet denoising and deep attenuation compensation are carried out on echo signals, sound path distance time delay and sound pressure amplitude parameters are extracted, defect identification and position estimation are carried out by utilizing a layered variational auto-encoder, a high-frequency transducer is switched to aiming at tiny defects, a harmonic component is extracted by adopting a nonlinear ultrasonic method, and a characteristic size is calculated; a defect distribution space feature matrix is generated based on a synthetic aperture focusing technology, a unified or personalized processing strategy is selected according to an acoustic characteristic homogenization degree evaluation value, a complete defect detection result is output, and the technical problem that deep weak defects in the electric insulation part are difficult to accurately detect and recognize is solved.

The invention relates to a laser radar on-chip integrated chip based on acousto-optic modulation, an on-chip acousto-optic scanning method and a laser radar system. A plurality of groups of interdigital transducers are arranged on the lithium niobate film, two groups of chirp IDTs respectively work at a low-frequency band and a high-frequency band, and sound waves at the low-frequency band correspondingly generate a relatively large Bragg deflection angle; and the high-frequency-band sound waves correspondingly generate a relatively small Bragg deflection angle. The two groups of IDTs work cooperatively, so that two-dimensional vector scanning of a dual-frequency broadband can be realized in a chip plane; the pair of focusing IDTs can form a focusing sound field in an action area, so that the light beam subjected to two-dimensional deflection is controllably deflected in the Z direction, and the chip is endowed with the three-dimensional scanning capability. The device is high in diffraction efficiency and low in power consumption; unification of large-range search and high-precision scanning is realized; z-axis deflection is realized by integrating a special focusing type interdigital transducer, a three-dimensional scanning function is realized on a monolithic integrated acousto-optic chip, and the structure is extremely compact.

The invention discloses an indoor and outdoor positioning method and system based on ultra wide band and satellite positioning fusion, and belongs to the technical field of indoor and outdoor positioning, and the method comprises the steps: collecting an outdoor initial coordinate of a first target through a satellite navigation system in an outdoor environment; the method comprises the following steps: in an indoor environment, continuously transmitting ultra-wideband signals to a first target through an ultra-wideband positioning system to obtain indoor relative coordinates of the first target; determining a coordinate processing strategy according to a signal intensity comparison result of the satellite navigation signal and the ultra-wideband signal; and based on a coordinate processing strategy, obtaining a final positioning coordinate by combining the outdoor initial coordinate and the indoor relative coordinate. Therefore, by implementing the application, the problem that in the prior art, indoor and outdoor high-precision positioning is difficult to realize at the same time, so that the positioning precision is greatly influenced by the movement of the positioning target can be solved.

The invention provides an intelligent warehousing equipment state information acquisition method and system, and relates to the technical field of intelligent warehousing, and the intelligent warehousing equipment state information acquisition method comprises the steps: obtaining the initial state data, collected by a multi-mode sensor group, of intelligent warehousing equipment, the multi-mode sensor group at least comprises a laser scanner, an ultra-wideband positioning base station and an equipment vibration sensor; performing dynamic estimation on the initial state data to obtain a prediction track of the intelligent storage equipment; generating a scanning path of the laser scanner according to the predicted track; and scanning the intelligent storage equipment based on the scanning path to obtain state information of the intelligent storage equipment. According to the intelligent storage equipment state information acquisition method and system, the technical problems of high equipment state updating delay and low acquisition efficiency caused by polling acquisition and PLC dependence in related technologies are solved.

The invention relates to the technical field of liquid crystal devices, and particularly discloses a normally-on flexible liquid crystal dimming film and a preparation method thereof. The structure of the normally-on flexible liquid crystal dimming film sequentially comprises a first flexible transparent substrate, a first vertical alignment layer, a dye liquid crystal layer, a second vertical alignment layer and a second flexible transparent substrate from top to bottom, wherein the materials of the first vertical alignment layer and the second vertical alignment layer are selected from side chain type transparent polyimide materials; the dye liquid crystal layer comprises black dichroic dye and negative phase liquid crystal. By accurately controlling the orientation arrangement of liquid crystal molecules, a high-precision pretilt angle is realized, the light modulation amplitude in a visible light broadband range reaches 45% or above, and the photoelectric property is equivalent to that of a normally dark (forward) mode liquid crystal dimming film.

The invention relates to the technical field of converter control, and provides a self-adaptive virtual impedance optimization method for a grid-forming type energy storage converter under a weak power grid, which comprises the following steps: injecting a multi-frequency-band collaborative disturbance signal into the power grid, acquiring a voltage response signal and a current response signal of the power grid, and carrying out online scanning and identifying the impedance characteristics of the power grid; establishing a power grid impedance model; constructing a real-time digital twinborn model synchronously operating with the physical converter, wherein the real-time digital twinborn model integrates the power grid impedance model and a multi-time scale state space model of the network-constructing type energy storage converter; and downloading the optimized virtual impedance parameter set to the physical networking type energy storage converter for execution, and performing closed-loop control of the adaptive virtual impedance. Therefore, the broadband stability and the dynamic performance of the network-forming type energy storage converter in the time-varying weak power grid environment are improved.

The invention discloses a frequency sweep measurement method and system. The method comprises the following steps: acquiring a fundamental frequency reference phase of each measured equipment access point at a measurement moment; executing rough scanning of the first-stage injection; analyzing the coarse scanning response data to identify a target frequency band which needs to be subjected to second preset resolution measurement; executing fine scanning of second-stage injection for the target frequency band; and analyzing the fine scanning response data, and obtaining a stability contribution evaluation result of each tested device to the power grid system based on an analysis result of the fine scanning response data and an analysis result of the coarse scanning response data. According to the scheme of the invention, the method can achieve the quick recognition of the potential key frequency region in a broadband range through the hierarchical rough scanning and fine scanning strategies, and avoids the time-consuming high-resolution measurement in a whole frequency band. And then, high-resolution fine scanning is performed on the identified target frequency bands in a targeted manner, so that accurate and detailed response data can be obtained in the key region.

The invention discloses an ultra-wideband RCS (radar cross section) reduction metasurface with mixed wave absorption and diffuse scattering and a wave-transparent window, and belongs to the technical field of electromagnetic metamaterials. The metasurface adopts a four-layer cascade structure and comprises a first layer of polarization conversion structure, a second layer of 2.5 D lossy structure, a third layer of Jerusalem cross-shaped lossy structure and a fourth layer of frequency selective surface structure. By loading a lumped resistor at a specific position and adopting a metal through hole interconnection technology, dual functions of radar cross section reduction in a 1-20GHz ultra-wideband and low insertion loss wave transmission in a 8-12GHz frequency band are realized. The structure of each layer adopts a highly symmetrical design and has the characteristic of polarization insensitivity, and meanwhile, by optimizing interlayer air gaps and dielectric material selection, the structure compactness is realized on the premise of ensuring the performance. The method has important application value in the aspect of integration of stealth equipment and a communication system.

The invention relates to the technical field of intelligent control of power electronic converters and induction heating, in particular to an intelligent control system of a medium-frequency power supply, which comprises a data acquisition module configured to acquire end-side voltage data and end-side current data of power conversion hardware in real time; the feature extraction module is configured to receive the end-side voltage data and the end-side current data and extract broadband waveform distortion features; the state evaluation module is configured to receive the broadband waveform distortion characteristics and calculate a model trust entropy value based on the broadband waveform distortion characteristics; the self-adaptive control module is configured to receive the model trust entropy value, trigger a second control mode to generate a second switch instruction and send the second switch instruction to the power conversion hardware; the model trust entropy represents a prediction deviation degree of a preset robust control model to the current real physical state of the power conversion hardware; according to the invention, the problem of insufficient perception of fine-grained service parameters in the background technology is solved.

The invention provides a miniaturized broadband non-reflection filtering antenna and communication equipment, and relates to the field of communication antennas. The antenna comprises a hybrid coupling resonance system and a matched absorption network, wherein the hybrid coupling resonance system comprises a main radiation groove which is formed in a metal floor and is of a split ring structure, and two parasitic radiation grooves which are of a U-shaped structure and are located on the two sides of the main radiation groove respectively; the matching absorption network comprises an absorption resistor connected with the feed microstrip line in parallel and an absorption microstrip line connected with the absorption resistor in series. According to the embodiment of the invention, the absorption circuit is integrated on the structure, so that the antenna has the non-reflection characteristic in the range of 1.27-2.31 GHz far beyond the radiation bandwidth, the defect that the radio frequency front-end performance is deteriorated due to in-band reflection and out-of-band energy reflection back to a transmitting channel of a traditional antenna is effectively overcome, and the electromagnetic compatibility and the linear characteristic of the whole system are remarkably improved.

The invention discloses a narrowband-broadband intelligent switching method of a radar, and belongs to the field of radar signal processing. Single radar wide-narrow band function integration is achieved through resource multiplexing, self-adaptive triggering and dynamic parameter configuration, detection tracking in a default narrow band mode is achieved, switching is triggered based on manual instructions and double thresholds, hardware such as a common antenna and a T / R assembly is reconstructed through time division multiplexing and software parameters, the signal synchronization time is shortened, and the target tracking response delay time is shortened; double-radar collaborative design is not needed, and the design workload is reduced. According to the invention, double radars are combined into a single radar, the hardware cost is greatly reduced, and the method is suitable for unmanned aerial vehicle-mounted, vehicle-mounted and other space-limited scenes and military reconnaissance, civil security and protection and other tasks.

The invention relates to a self-adaptive tuning inerter damping device and method for suppressing vertical micro-vibration of a structure. The self-adaptive tuning inerter damping device comprises a bearing base, a tuning mass block, a vibration system connecting the bearing base and the tuning mass block, a pneumatic control system and an intelligent measurement and control system. The vibration system is formed by connecting an outer side air spring set and a central air spring in series with a hydraulic inerter unit, an adjustable damping branch and a fixed inerter branch which are connected in parallel are integrated in the hydraulic unit and are respectively provided with an electro-hydraulic proportional valve and a spiral pipe type hydraulic inerter, so that adjustable damping and mass amplification are realized. The pneumatic system adjusts the air pressure of each air spring through an independent air path and a proportional valve so as to change the rigidity. An intelligent system monitors vibration through a sensor, a central controller identifies excitation frequency and optimizes parameters based on a kinetic model, and rigidity and damping are synchronously adjusted. According to the invention, the problem that a mechanical inerter is insufficient in response to micro-vibration is solved, the defects that a traditional passive device is narrow in frequency band and easy to detune are overcome, and broadband, self-adaptive and high-performance suppression of vertical micro-vibration of a structure is realized.

The invention relates to the technical field of unmanned aerial vehicle interference, and provides an unmanned aerial vehicle communication link countering system based on a Vivaldi antenna, an antenna array, and the system comprises a signal receiving unit and a signal transmitting unit. Wherein the antenna array is formed by fixing at least two groups of Vivaldi antenna units which are arranged in a staggered manner in the extensible mechanical frame; the broadband interference component is used for responding to the spectrum signal of the to-be-suppressed unmanned aerial vehicle through a receiving unit and generating a first interference signal; wherein the interference frequency band corresponding to the first interference signal is the same as the real-time communication frequency band of the to-be-suppressed unmanned aerial vehicle, and the extensible mechanical frame is used for responding to the first interference signal and determining the number and angle of the expanded area arrays.

According to the low-insertion-loss broadband balun equivalent circuit for the base station and the balun thereof, the low-insertion-loss broadband balun equivalent circuit is based on the LTCC (Low Temperature Co-fired Ceramic) technology, the Marchand structure principle design is adopted, a 1 / 4 wavelength coupling line is realized through a broadside coupled spiral structure, the size of the balun is greatly reduced, meanwhile, two groups of coupling transmission lines adopt a folding mode, the three-dimensional wiring advantage of the LTCC technology is fully utilized, and the size of the balun is greatly reduced. Signal shielding cover is carried out in the middle through GND, crosstalk between two groups of coupling transmission lines is avoided, and the novel base station has the functional characteristics of small insertion loss, good amplitude flatness, high phase consistency, broadband and small size.

The invention relates to the technical field of information, in particular to a black land plough layer thickness analysis method based on machine learning. The scheme has the advantages that double-frequency radar signals (200MHz low frequency and 2GHz high frequency) are combined with power amplification and a broadband antenna, a double-layer feature comparison model is constructed by utilizing the frequency sensitivity inversion characteristic of dielectric constant difference between a plough layer and a plough pan, interface details are captured in cooperation with a 1GS / s super-Nyquist sampling rate, a strong regression model is constructed in combination with an AdaBoost algorithm, and a high-precision feature comparison model is constructed. The method achieves the high-precision, non-destructive and large-area rapid detection of the thickness of the plough layer of the black land, and solves the problems that a conventional method is time-consuming and labor-consuming, is low in precision, and cannot give consideration to the penetration depth and resolution of a single-frequency radar.

The invention designs a broadband intermediate-frequency heterogeneous integrated communication transceiving micro module and a three-dimensional packaging method, and belongs to the technical field of advanced packaging. The micro module comprises a TSV silicon adapter plate, a Fan-out module, an HTCC ceramic substrate and a digital chip. The TSV silicon adapter plate adopts a high-resistance silicon substrate, and a coaxial shielding TSV structure is arranged on the TSV silicon adapter plate and comprises an inner layer signal through hole and an outer layer grounding layer. A frequency synthesizer chip and a radio frequency chip are embedded in the Fan-out module, and high-density horizontal interconnection is realized through a plurality of redistribution layers. The HTCC ceramic substrate is of a multi-layer laminated structure, and an impedance matching network is arranged in the HTCC ceramic substrate. The three-dimensional packaging method comprises the steps of TSV silicon adapter plate preparation, Fan-out module processing, digital chip stacking and system-level integration. High-density packaging of the radio frequency chip and the digital chip is achieved through the three-dimensional heterogeneous integrated architecture, and low-loss transmission of broadband signals is guaranteed through the coaxial shielding TSV structure and the impedance matching network.

The invention discloses a rectangular waveguide sealing window structure for realizing broadband transmission, which belongs to a microwave signal detection device and comprises a first rectangular waveguide cavity, a second rectangular waveguide cavity and a rectangular dielectric block arranged between the first rectangular waveguide cavity and the second rectangular waveguide cavity, the first rectangular waveguide cavity comprises a first rectangular waveguide shell and two first stepped transition structures embedded into an inner cavity of the first rectangular waveguide cavity, and the second rectangular waveguide cavity comprises a second rectangular waveguide shell and two second stepped transition structures embedded into the second rectangular waveguide shell. The opposite side faces of the two first stepped transition structures and the two second stepped transition structures are provided with identical tooth-shaped steps, the second rectangular waveguide shell is further internally provided with an installation cavity communicated with the second I-shaped sliding groove, the two waveguide cavities are connected through screws, and the rectangular dielectric block is fixedly installed in the installation cavity. The vertically symmetrical multi-stage stepped impedance matching network provided by the invention realizes excellent transmission performance with low voltage standing-wave ratio in a wide frequency band, and is suitable for a millimeter wave system with high power and wide frequency band.

The present disclosure provides a method for providing a service by using an ultra wide band (UWB) communication. The method for a first UWB device, according to an embodiment of the present disclosure, comprises the steps of: receiving a downlink time difference of arrival (DL-TDoA) message from at least one UWB anchor through a UWB channel; confirming on the basis of the DL-TDoA message that positioning of the first UWB device has failed; receiving a ranging message including position information about a second UWB device from the second UWB device; and measuring the position of the first UWB device on the basis of the DL-TDoA message and the position information about the second UWB device.