73 results about "Fresnel zone" patented technology

The invention provides a multi-modal gait user identification method and system based on WiFi acoustics. The method comprises the following steps: a user freely walks in an indoor equipment range; the method comprises the following steps: acquiring a WIFI signal by using commercial WIFI equipment, extracting a CSI feature from the WIFI signal, calculating a PLCR, and constructing a Fresnel zone elliptical model; a microphone array is used for collecting footstep sound, a footstep sound AoA sequence is calculated from sound signals, and a ray model is constructed; confirming a user moving track through multi-modal fusion; a trajectory and a PLCR spectrum are utilized. Mapping and deriving an independent velocity spectrum; and training a gait recognition model by using the independent velocity spectrum as a sample to realize user recognition. According to the invention, the technical problems of poor adaptability to complex scenes, high deployment difficulty, environment interference and poor robustness are solved.

The invention discloses an achromatic self-focusing spinning terahertz emitter and a preparation method, and particularly relates to the field of spinning terahertz emitting equipment, and the achromatic self-focusing spinning terahertz emitter comprises a glass substrate, a spinning terahertz thin film and a magnet pair, wherein the spin terahertz film is formed by alternately arranging a ferromagnetic material and two heavy metal non-magnetic materials with the same spin Hall angle and opposite directions on the ferromagnetic material. According to the achromatic self-focusing spin terahertz emitter, the spin terahertz Fresnel zone plate is constructed by specially arranging two heavy metal non-magnetic materials with the spin Hall angles equal in size and opposite in direction, so that generated spin terahertz waves of more than two frequency bands are converged to the same point, the terahertz generation efficiency is high, and the terahertz wave generation efficiency is high. And meanwhile, the integration level of the spinning terahertz emitter is improved.

The invention relates to the technical field of seismic exploration, in particular to a seismic offset angle gather generation method and device, equipment and a medium. The method comprises the following steps: acquiring pre-stack seismic data of a work area after preprocessing; performing pre-stack time migration on the pre-stack seismic data, and performing grouping accumulation according to inclination angles in the pre-stack time migration process to generate an inclination angle gather; according to the inclination angle gather, picking up Fresnel zone boundaries of reflection events of all imaging points according to preset intervals; stable-phase offset is carried out by using the picked Fresnel zone boundary, and an offset angle gather of stable-phase control is generated according to grouping accumulation of incident angles in the offset process. The problems that an existing method for generating an angle gather through pre-stack depth migration is difficult in interval velocity modeling and high in calculation cost are solved.

The invention provides a Fresnel zone pickup model, a training method and a diffracted wave imaging method based on machine learning. The training method comprises the following steps: acquiring seismic wave training data; a Fresnel band label is marked for the horizontal slice image set of the initial 3D dip angle gather, and a real label set is obtained; inputting the horizontal slice image set of the initial 3D dip angle gather and the real label set into a pre-constructed Fresnel zone pickup model for iterative training to obtain a prediction result of a Fresnel zone; during each training, updating parameters of a Fresnel zone pickup model based on a real label of the Fresnel zone and a loss value of a prediction result; and a preset iteration condition is reached. According to the diffracted wave imaging method, diffracted wave imaging is carried out by using a trained Fresnel band pickup model. According to the method, the neural network is introduced on the basis of the 3D dip angle gather to pick the Fresnel zone, so that the precision of the picked Fresnel zone is higher, and the precision and efficiency of diffracted wave imaging are improved.

The invention discloses an ultrasonic focal region regulation and control system and method for realizing focal region local composite motion in superficial tissue. The ultrasonic focal region regulation and control system comprises a transducer, a cavity, a regulation and control structure and an acoustic Fresnel zone plate FZP, under the adjusting effect of the adjusting structure, the ultrasonic generator can reciprocate in the axial direction of the cavity and is used for adjusting the focal region form of the ultrasonic waves emitted by the transducer, so that the ultrasonic waves irradiate the cells at the target position. The system can effectively regulate and control the form of the focal region of the sound field, so that the effects of generating a variable force field effect on tissues in the range of the focal region, uniformly outputting energy, expanding the action area and improving the cell irradiation effect and safety are achieved. According to the ultrasonic cell irradiation device, the complexity of a traditional ultrasonic cell irradiation device in the operation process is reduced, the operation frequency and difficulty are greatly reduced, a cell irradiator can more concentrate on optimization of a treatment scheme, and meanwhile treatment convenience and efficiency are effectively improved. A high-precision sound field regulation and control technology is combined with a humanized mechanical design.

An antenna module and communication device containing the antenna module are disclosed. The antenna module is disposed in a metal cavity. The antenna module includes a switched beam mm-wave antenna array having radiating elements separated by less than a wavelength of the radiating elements. The array is fed by a single transceiver chain. The array is disposed at the focal length of a low-profile mm-wave lens configured to steer the beam. A sub-10 GHz antenna is disposed closer to the opening of the cavity than the lens. The lens is a Fresnel Zone Plate lens having a focal length of less than about the wavelength of the beam, or a Saucer lens having shells of different refractive indexes and having a profile that is more than 6 times smaller than a Luneburg lens with a same focal length.

The present invention discloses a design method for a replacement model of a Fresnel zone patch antenna that integrates physical mechanisms, and belongs to the field of antenna design technology in artificial intelligence technology and communication technology. The method includes: calculating the physical parameters of the Fresnel zone patch antenna; calculating the estimated gain data and theoretical gain data of the Fresnel zone patch antenna with different physical parameters within a preset radiation angle range; constructing a deep neural network model, and training the deep neural network model using data in a training set and label data; using the trained deep neural network model as a replacement model for the Fresnel zone patch antenna, and using the replacement model to predict the gain at different radiation angles. The replacement model designed by the present invention can quickly and accurately predict the gain within the main radiation angle of the FZPA. Compared with traditional replacement models, it has high accuracy, fast speed, low training cost, and significantly higher efficiency than traditional FZPA design methods.

The invention belongs to the technical field of micro-nano processing, and particularly relates to a Pt-HSQ-based high-resolution X-ray Fresnel zone plate and a preparation method thereof. According to the X-ray Fresnel zone plate, a Pt-HSQ metal-inorganic material system is adopted, a diffraction structure with a large aspect ratio and Pt material quasi-periodic dense stripes specially needed by an X-ray zone plate lens is formed through electron beam lithography and an ALD process, and diffraction focusing from a soft X-ray wave band to a hard X-ray wave band and imaging with an amplification function are achieved. The wave zone plate has excellent mechanical stability, and the irradiation resistance and morphology retentivity of the wave zone plate under high-energy irradiation are remarkably improved. And high-resolution X-ray focusing elements with different energy wavebands and different focal lengths can be prepared according to geometric design and material selection of the wave zone plate. The lens is suitable for microscopic imaging, coherent diffraction imaging, X-ray spectrum, nanometer detection and other scenes of a synchrotron radiation or off-line laboratory X-ray light source, and has wide popularization value and application prospect.

The present disclosure relates to a method and a system for determining a set of target backhaul locations The method includes receiving at least a geographical location data associated with a set of input location data. The method includes identifying a target input location based on the set of input location data and identifying backhaul location(s) in a predefined range of the target input location. Further, the method includes determining at least one of: a distance, a line of sight (LOS), and clearance of a predefined Fresnel zone from the target input location to the one or more backhaul locations. The method includes identifying a set of target backhaul locations from the one or more backhaul locations based on at least one of: the distance, the line of sight, and clearance of the predefined Fresnel zone from the target input location to the one or more backhaul locations.

The invention discloses a multi-focus composite Fresnel phase diagram rapid generation and power equalization method and system for one-to-many free space laser communication. According to the method, aiming at a scene in which a plurality of user targets are located at different directional angles and different propagation distances, a focusing + directional single-beam phase is constructed for each target on the basis of analyzing a Fresnel zone lens phase and a linear tilt phase, and the phase is taken after complex field superposition is performed according to a preset power weight, so that the target target is obtained. A composite phase diagram for a phase-type spatial light modulator (SLM) is directly obtained. The power weight is preset according to a link budget or a task demand so as to realize on-demand distribution and equalization of multi-beam output power; and meanwhile, fixed phase bias can be introduced to each beam to suppress inter-beam interference fringes. According to the method, frame-by-frame iterative solution is not needed, the calculation complexity is low, and high-frame-rate and low-delay online updating is easy to realize.

An installation position calculation device of a relay station according to an embodiment includes: an identification circuitry configured to identify an installed station candidate point at which an LOS region from the relay station is maximized in an installed station candidate range or among a plurality of installed station candidate points predetermined as installation position candidates; a correction circuitry configured to correct a position of each of the identified installed station candidate points based on a Fresnel zone for the relay station; a storage circuitry configured to store, as an installation position of the relay station, the position of the installed station candidate point at which an LOS region from the relay station is maximized among each of the identified installed station candidate points or the corrected installed station candidate points; and a controller configured to control such that the number of installation positions of the relay station.

The present invention relates to a reactor and to a method for depositing one or more atomic layers of at least one material onto a substrate. The reactor comprises a reaction chamber accommodating a showerhead, a base stage and at least one substrate holder. The showerhead comprises at least one gas outlet that is configured for providing a gas stream of the at least material or of at least one component of the at least one material. The base stage is rotatable around a base stage rotation axis. The at least one substrate holder is arranged on the base stage and configured for rotating the substrate around a substrate rotation axis. In particular, the substrate holder is configured for rotating the substrate around a substrate rotation axis in such a way that the base stage rotation axis and the substrate rotation axis are inclined with respect to each other. The present invention also relates to an X-ray microscope for producing a magnified image of an object using X-rays.

The application provides a tracking method and device based on a Fresnel region, electronic equipment and a storage medium, comprising: determining a target moving speed of a passive target based on frequency domain channel estimation information; taking a plurality of grids in an environmental coordinate system as initial positions, and constructing candidate motion trajectories based on the target moving speed at a plurality of observation times; for each candidate motion trajectory, and a PDP observation ratio of the observation time corresponding to each coordinate position in the candidate motion trajectory, determining an energy hot spot trajectory diagram; for each candidate motion trajectory, judging whether the energy hot spot trajectory diagram corresponding to the candidate motion trajectory matches a signal strength hot spot diagram corresponding to the environmental coordinate system, and taking the candidate motion trajectory corresponding to the energy hot spot trajectory diagram matched with the signal strength hot spot diagram as a tracking result of the passive target. The application realizes accurate tracking and positioning of the passive target.

The application provides a vehicle wireless non-contact sensing method and system based on channel state information, uses decimeter waves as a signal source for wireless sensing, is not affected by ambient light, has high non-contact sensing surrounding environment sensing precision, determines an obstacle through window calculation of a moving energy value, rejudges confidence of the obstacle to confirm a target object, realizes accurate positioning of the target object through construction of a boundary intersection point of mutually perpendicular Fresnel zones, is easy to realize and apply, effectively reduces misrecognition of automatic driving vehicle sensing, can realize wireless non-contact sensing and positioning, has high sensing precision, and has great application prospect.

The application discloses a tunnel earthquake advanced prediction small-aperture imaging and automatic interpretation method, and belongs to the technical field of tunnel engineering geological exploration. Seismic wave data is collected through setting an observation system, and Fresnel body functions are calculated based on the Fresnel condition and a constant-speed medium model after filtering F c , the F c The weight factor is substituted into a Kirchhoff migration imaging formula to complete constraint imaging calculation, and imaging results are output; the imaging color profile is read and converted to an HSV color space, color threshold values are adaptively adjusted based on hue and saturation components, and after multi-scale contour detection fusion and contour grouping optimization, key geological targets are labeled and visualized output; the application realizes F c Fresnel zone correction, solves the problems of small-aperture imaging arc drawing and low resolution; the data-driven automatic interpretation process eliminates the multi-solution nature of manual interpretation, improves prediction accuracy and efficiency, and the imaging results are more in line with actual geological conditions, thereby providing reliable support for tunnel construction safety.

The present application discloses a diffraction wave imaging method, an electronic device and a medium. The method includes: Step 1: For the data of one receiving line in a single-shot record, calculate the imaging range of this receiving line, and for each imaging point within the imaging range, perform the following steps: Step 101: Extract the amplitudes on each recording trace on this receiving line along the diffraction hyperbola for the imaging point; Step 102: Calculate the weight coefficient for suppressing the strong energy band corresponding to the imaging point; Step 103: Perform Kirchhoff time migration processing according to the weight coefficient; Step 2: Process the data of all receiving lines in all single-shot records in sequence, and accumulate the migration results falling on the same imaging point to obtain the final diffraction wave imaging result. The present invention locates the center position of the strong energy band through energy scanning, determines the range of the strong energy band based on the principle of the Fresnel zone, and suppresses the reflection wave imaging by superimposing the remaining energy outside the strong energy band, highlighting the diffraction wave imaging.

This invention discloses an indoor wireless positioning method based on WiFi and acoustic multimodal combination, comprising the following steps: A user moves freely within the sensing scene; a commercial WiFi device collects the user's CSI (Continuous Sensor Indicator) during movement, extracts the PLCR (Pulse Path Length) from the CSI, calculates the path length of the reflected signal, and constructs a Fresnel zone elliptical model; a microphone array collects the user's footsteps during movement, and the sample offset of different microphone pairs is solved by the peak value of the cross-correlation function of each pair of microphone signals; an angle is calculated based on the sample offset to construct a ray model; the Fresnel elliptical model and the ray model are combined to calculate the error, and the user's positioning and tracking are completed through maximum likelihood optimal estimation. Compared with traditional WiFi positioning methods, this invention eliminates the additional phase calibration cost and improves tracking accuracy; compared with traditional acoustic tracking systems, tracking is possible even if the user does not actively issue voice commands, achieving true passive tracking.

The invention discloses a mirror scattering region clutter signal simulation method and device under a space-based double-station detection system. The method comprises the following steps: determining a clutter scattering region according to a beam irradiation relation based on a detection geometric model; determining a mirror scattering area in the clutter scattering area, and determining the area except the mirror scattering area in the clutter scattering area as a non-mirror scattering area; respectively calculating the area of the mirror scattering region and the area of the non-mirror scattering region; respectively calculating a scattering coefficient, clutter gain, total distance history of clutter and clutter amplitude; and constructing a radar equation according to the areas of the mirror scattering region and the non-mirror scattering region, the scattering coefficient, the clutter gain, the total distance history of the clutter and the clutter amplitude, and constructing a clutter signal model according to the radar equation. According to the method provided by the invention, the projection area of the first Fresnel region on the ground is used as the area of the mirror scattering region, so that the clutter energy distribution of the mirror scattering region is more accurate, the modeling of the clutter signal is more accurate, and the simulation precision of the clutter signal is improved.

The present invention is a Fresnel zone plate lens which improves radio wave reception sensitivity by suppressing the radio wave shielding action of a conductive film while reducing an installation space, and said Fresnel zone plate lens has a base 10, transmission sections T which are formed in a conductive film 20 on the base 10 and allow radio waves to pass therethrough, and shielding sections S which are formed in the conductive film 20 on the base 10 and have a lower degree of radio wave transmittance than the transmission sections T. The transmission sections T and the shielding sections S are disposed alternatingly in concentric circles form a Fresnel zone plate lens (FZPL) 2 that focuses, on a focal point, radio waves having a first wavelength λ1. The transmission sections T have a frequency selective surface (FSS) structure which allows radio waves having the first wavelength λ1 to pass therethrough.

This application provides a method, apparatus, device, and computer-readable storage medium for determining the extension length of an observation line in seismic exploration. The method includes: acquiring layer information of a target layer; the layer information including depth, velocity, maximum dip angle, and the dominant frequency of the target layer's location; determining the offset aperture for the target layer to meet the first Fresnel zone requirement based on the velocity and the dominant frequency; determining the offset aperture for the target layer to meet the 30-degree diffraction repositioning requirement based on the depth; determining the offset aperture for the target layer to meet the stratigraphic dip angle requirement based on the depth and the maximum dip angle; and determining the extension length of the observation line based on each offset aperture. The observation line extension length determined by this method can meet the offset repositioning imaging requirements of all reflection points, improving the acquisition accuracy of the observation system.

The application discloses a fluid antenna source positioning method and device based on aperture dynamic reconfiguration, and relates to the technical field of wireless communication and array signal processing. The application is proposed to solve the problems of limited positioning accuracy and insufficient environmental adaptability caused by fixed array structure and single source field model. The steps are as follows: S1. Constructing a fluid antenna system S-FAS with adaptive aperture adjustment capability, and establishing a unified modeling framework based on accurate spatial geometry ESG; S2. Switching between compressed and expanded apertures according to task requirements, collecting observation data and generating statistics; S3. Estimating the direction under the compressed aperture and suppressing mutual coupling and amplitude and phase errors; S4. Jointly estimating the target direction and distance under the expanded aperture with the initial value as the anchor point to realize high-precision positioning. The application can work stably in a near-field, Fresnel zone and far-field multi-source mixed environment without distinguishing source types or isolating signals, has high precision, low complexity and strong adaptability, and is suitable for intelligent sensing and low-altitude communication scenes.

The application belongs to the technical field of structured light, and relates to a structured light three-dimensional reconstruction system and method based on a fold-diffraction hybrid imaging. The system comprises a structured light projection module, a fold-diffraction hybrid imaging module, a target object and a data processing module. The structured light projection module, the fold-diffraction hybrid imaging module and the target object are arranged at intervals. The structured light projection module is connected with the data processing module to emit structured light and produce diffuse reflection on the surface of the target object. The fold-diffraction hybrid imaging module comprises filter plates, Fresnel zone plates, liquid lenses, solid lenses and near-infrared cameras arranged at intervals. The filter plates receive the diffuse reflected light and transmit the light to the near-infrared cameras in turn. The liquid lenses are connected with the data processing module to switch the structured light detection mode by controlling the input voltage of the liquid lenses. The data processing module is connected with the near-infrared cameras to collect multi-line structured light images and realize three-dimensional reconstruction. The application can switch the structured light detection mode.

The invention discloses a fluid antenna source positioning method and device based on aperture dynamic reconfiguration, and relates to the technical field of wireless communication and array signal processing. The scheme is provided for solving the problems of limited positioning precision and insufficient environmental adaptability caused by a fixed array structure and a single source field model. The method comprises the following steps: S1, constructing a fluid antenna system S-FAS with adaptive aperture adjustment capability, and establishing a unified modeling framework based on precise space geometry ESG; s2, switching between aperture compression and aperture expansion according to task requirements, collecting observation data and generating statistics; s3, direction initial estimation is carried out under the compressed aperture, and mutual coupling and amplitude-phase errors are suppressed; and S4, performing joint estimation on the target direction and distance by taking the initial value as an anchor point under the expanded aperture to realize high-precision positioning. The method does not need source type distinguishing or signal isolation, can stably work in near-field, Fresnel region and far-field multi-source mixed environments, has high precision, low complexity and strong adaptability, and is suitable for scenes such as intelligent sensing and low-altitude communication.

This invention discloses a fast autofocusing method for layered imaging based on vortex edge enhancement and selective linear fitting, comprising: acquiring the initial complex amplitude of an object; propagating the initial complex amplitude to a virtual Fresnel zone plate, modulating it to generate a hologram, extracting edge information during the backpropagation of the hologram, locating the region of interest (ROI), and calculating the sharpness bias within this ROI, storing it along with the corresponding axial distance in a historical dataset; during iterative iteration, substituting the updated distance parameters for each iteration of the layered imaging algorithm, classifying all data points in the historical dataset into linear or saturated intervals, performing least-squares fitting on data points classified as linear intervals, outputting the intercept and slope of the fitting function, and calculating new axial distances based on the current data point classification using different strategies, before proceeding to the next iteration. This invention enables high-precision and high-efficiency automatic calibration in a single preprocessing step.

Provided are: a diffractive optical element that is thin, realizes high mass productivity, has a high light-condensing performance which makes it possible to cope with a minute pixel pitch, and is capable of condensing light of a plurality of wavelengths; and a method for manufacturing the diffractive optical element.　The diffractive optical element comprises: a base board which allows entering light to pass therethrough; and a resin layer which is formed from a curable resin composition, forms recesses and projections on a main surface of the base board, and also forms a diffraction pattern that is substantially concentrical when viewed in a direction orthogonal to the main surface of the base board. The diffraction pattern is divided into a plurality of pattern regions in the circumferential direction. The plurality of pattern regions at least include: a first pattern region which has a shape of a Fresnel zone plate, and which corresponds to light that is included in the entering light and that belongs to a first wavelength range; and a second pattern region which has a shape of a Fresnel zone plate, and which corresponds to light that is included in the entering light and that belongs to a second wavelength range different from the first wavelength range.

This invention discloses a depth measurement and edge extraction method based on a single all-dielectric metasurface, belonging to the fields of micro-nano optics and image information extraction applications. The phase distribution of the all-dielectric metasurface is obtained using the Fresnel zone method. Each Fresnel region corresponds to a spiral phase with a different topological charge number, increasing sequentially from the inside out, generating a double-helix point spread function. The metasurface is placed on the spectral plane of a 4f system, with a pair of linear polarizers and a quarter-wave plate placed before and after it respectively, achieving corresponding circular polarization selection and ensuring phase modulation based on the geometric phase modulation principle, thus obtaining the designed metasurface optical system for depth measurement and edge extraction. When incoherent light is incident, the main lobe rotation angle of the double-helix point spread function corresponding to the "twin image" is extracted using image cepstral analysis, thus deducing the object's depth information. When coherent light is incident, the incident light interacts with the central part of the metasurface. Through the convolution of the target object with the spiral phase, coherent destructive phase can be achieved for regions with uniform phase / amplitude, extracting the edge information of the target object. This invention enables both depth measurement and edge extraction.

The utility model belongs to the technical field of terahertz dual-function switchable surface plasmon polaritons, provides a novel method for realizing a dual-function switchable SPs (Surface Plasmon polaritons) device on a GST metasurface, is low in cost, and provides a switchable surface plasmon polariton system based on GST. The structure is as follows: a spin correlation directional SPs coupler is formed by a Fresnel zone plate covered with a non-volatile phase change material GST, odd half-wave zones of the Fresnel zone plate are bright zones, and even half-wave zones of the Fresnel zone plate are covered with GST and are dark zones; the normal phase change from an amorphous state to a crystalline state of the GST is realized by setting an annealing temperature on a heating table to heat the GST, the inverse phase change from the crystalline state to the amorphous state is realized by irradiating the GST through nanosecond laser generated by a laser, and the excitation of plane waves SPs or the excitation of focused SPs is realized. The switchable surface plasmon device is mainly applied to design and manufacturing occasions of switchable surface plasmon devices.

The present application relates to a kind of signal dynamic shielding error reduction method and system.This method constructs the ranging model about the projection of Fresnel zone to two-dimensional plane according to the UWB device of Anc and Tag, and the wearer Wearer of label Tag;The blocking degree index DFO of Wearer is calculated by ranging model, and ranging model is optimized using DFO to reduce shielding error;In the optimized ranging model, when Wearer is in the Fresnel zone ellipse, the actual blocking length of Wearer to the Fresnel zone ellipse is calculated;The range of truncated relative heading angle RHA is calculated in combination with blocking length.The present application establishes mathematical model by projecting the UWB device of Tag and Anc, wearer and Fresnel zone to two-dimensional plane, and is optimized in combination with index DFO, effectively reduces the error in positioning process.

The purpose of the present invention is to provide a diffractive optical element having improved shape stability.　This diffractive optical element causes diffraction with respect to incident light, and comprises a substrate that transmits the incident light, a fine structure that is composed of a curable resin composition and forms an unevenness on a first main surface side of the substrate to form a diffraction pattern for diffracting the incident light, and a first protective layer that is transmissive to the incident light and covers the fine structure, the fine structure exhibiting any of a Fresnel zone plate shape, a linear zone plate shape, a fractal zone plate shape, and a photon sieve plate shape when viewed in a direction orthogonal to the first main surface.

The application provides a two-dimensional curved wide-line dip-angle domain stable-phase pre-stack time migration method, device and equipment, and relates to the technical field of seismic exploration data processing. The method comprises the following steps: obtaining original two-dimensional curved wide-line seismic data; determining common midpoint distribution and migration velocity field according to the original two-dimensional curved wide-line seismic data. For each common midpoint, the tangential azimuth of the common midpoint is calculated according to the common midpoint distribution and the migration velocity field, and a dip-angle gather distributed along the tangential azimuth is constructed. According to the dip-angle gather, the corresponding dip-angle domain Fresnel zone at each imaging point is determined. According to the dip-angle domain Fresnel zone, two-dimensional curved wide-line dip-angle domain stable-phase pre-stack time migration is performed, migration results under different migration distances are generated, and the migration results are stacked to generate a migration profile. The method is used to achieve the effect of effectively balancing imaging integrity and signal-to-noise ratio when pre-stack time migration processing of two-dimensional curved line data is performed.