756 results about "Scan angle" patented technology

The invention relates to a steel truss girder digital pre-assembly method and system based on three-dimensional laser scanning, and belongs to the technical field of constructional engineering. The method comprises the following steps: calculating a three-dimensional coordinate and a scanning angle of a scanning observation station based on a steel truss girder design model and field environment point cloud data to obtain observation station layout position parameters; controlling a three-dimensional laser scanner to scan the steel truss girder section by section according to the arrangement position parameters of the observation station, and acquiring original point cloud data of each section of the steel truss girder; performing spatial alignment and noise reduction processing on the original point cloud data to obtain standardized point cloud data; based on the standardized point cloud data, feature parameters of all the segments are segmented and extracted, digital splicing is carried out, and a steel truss girder three-dimensional point cloud model is generated; based on the steel truss girder design model and the steel truss girder three-dimensional point cloud model, the displacement deviation value and the angle deviation value between the segments are calculated, and an assembly error result is obtained; and generating a construction correction parameter set based on the assembly error result. The assembling precision of the steel truss girder can be improved.

The invention belongs to the technical field of three-dimensional imaging and measurement, and particularly discloses a laser scanning three-dimensional imaging method and device, a medium and equipment, and the method comprises the steps: obtaining laser scanning data of a target object, and the laser scanning data comprises depth data including reflection intensity, a scanning angle, a timestamp and flight time; preprocessing the laser scanning data, and fusing a time sequence and scanning path information to obtain multi-channel input features adaptive to a neural network; constructing a three-dimensional geometric reconstruction model, and training the model; inputting the multi-channel input features into a trained three-dimensional geometric reconstruction model to obtain a dual-channel output tensor containing a dense depth map of the target object and a corresponding uncertainty map; converting the dual-channel output tensor comprising the dense depth map of the target object and the corresponding uncertainty map into a three-dimensional point cloud under world coordinates; and post-processing the three-dimensional point cloud to obtain a three-dimensional image of the target object.

The invention relates to the technical field of new energy power plant construction data processing, in particular to a construction site personnel track recognition system based on a two-dimensional code, which adopts laser etching to dynamically encrypt a two-dimensional code label, and improves the weather resistance of the label in a salt fog environment through a salt-dredging nano coating and antistatic packaging. And a double-fixing structure combining the elastic binding band and the magnetic fastener is suitable for high-strength operation scenes. Industrial-grade scanning base stations are deployed in a construction area in a gridding mode, three-dimensional coordinate data are captured through a multi-base-station cooperative scanning mechanism, high-reflection interference of photovoltaic panels is eliminated through a signal intensity difference algorithm, and a de-noising coordinate set is generated. The closed-loop calibration module corrects scanning angle offset and earth surface reflection weight parameters through a three-level check link, the environment adaptation module triggers an ultrasonic multi-frequency cleaning program to maintain optical performance, and the cooperative control unit adjusts the light supplementing intensity and the data fusion proportion in a linkage mode. Accurate identification of personnel tracks and multi-working-plane dynamic management and control in a complex environment are realized.

The invention discloses an array antenna phase-only real-time beam scanning and side lobe control method based on machine learning. Firstly, array geometry, scanning angles and minor lobe indexes are set; and then, array element excitation phases meeting requirements are rapidly synthesized by using a phase-only fast Fourier FFT (Fast Fourier Transform) algorithm. Constructing a training data set by taking the scanning angle and the minor lobe index as input and the corresponding phase distribution as output; training a neural network by using the data set to obtain a real-time prediction model from initial excitation distribution to accurate excitation distribution; and according to a target expected directional diagram scanning angle and a sidelobe feature, inputting the scanning angle and the sidelobe feature into a neural network to predict and obtain an array element excitation phase so as to realize a real-time phase-only beam and sidelobe control function. Input dimensions are reduced by extracting key features of a directional diagram, data generation is accelerated by means of FFT, real-time performance and precision are both considered, and the method is suitable for fast beam scheduling tasks of various array antennas.

The invention belongs to the technical field of antenna engineering, and particularly relates to an ultra-wide-band low-profile phased-array antenna, which realizes broadband impedance matching characteristics and effectively expands the working bandwidth of the antenna by optimizing a dipole arm structure and introducing a matching branch knot and linear tapered slot composite structure on a radiation unit layer; on the array architecture level, an electromagnetic metasurface technology is adopted, array current distribution is improved through a periodic artificial electromagnetic structure, the active standing-wave ratio is remarkably reduced, the scanning angle of an array is widened, and meanwhile high compression of a system profile is achieved; on the structural design level, a three-dimensional composite structure of a transverse metal floor, a longitudinal radiation layer and a transverse metasurface layer is innovatively constructed, and the overall section height is reduced to 0.137 lambda Low (lambda Low is the lowest working frequency wavelength) through electromagnetic coupling and space folding technologies; in conclusion, the ultra wide band (the relative bandwidth is greater than or equal to 90%) and the low profile (lt; and the method is suitable for a new generation of broadband phased array radar system.

Disclosed are a wide-angle beam-scanning phased array based on near-field coupling and port self-decoupling and a design method thereof. This design method is different from traditional methods that require introduction of additional beam-broadening and decoupling structures, but aims to obtain wide-beam active element pattern by cleverly utilizing a near-field coupling effect between elements. Meanwhile, port self-decoupling technology is introduced into the phased array to achieve high port isolation and improve beam gain at large scanning angle. Therefore, a phased array with an extremely simple structure and an excellent beam-scanning performance, can be constructed based on typical narrow-beam antenna elements, without requiring additional beam broadening and decoupling structures.

The invention belongs to the field of synthetic aperture radars, and discloses a high-orbit SAR sliding bunching working mode design method and system. The method comprises the steps that 1, resolution improvement factors of a high-orbit SAR in different orbit satellites are calculated; 2, according to resolution improvement factors of the high-orbit SAR in different orbit satellites, calculating a sliding speed of a sliding bunching mode antenna beam on the ground; 3, calculating the antenna beam angle scanning speed according to the sliding speed of the antenna beam in the sliding bunching mode on the ground; and 4, calculating the scanning angle of the antenna beam according to the observation breadth required by the azimuth. According to the method, the problem that a traditional sliding bunching working mode design and calculation method of the high-orbit SAR fails is solved, the influence of satellite speed time varying and earth rotation on the sliding bunching working mode design of the high-orbit SAR is considered, the precision of the working mode design of an SAR system can be greatly improved, and the method has important application prospects.

A VTOL UAV comprising a chassis, a propulsion system mounted on the chassis, electronics including a flight control system, and a 3D LIDAR sensor mounted on the chassis. The 3D LIDAR sensor has a laser beam 360° rotation axis (R) and an azimuthal scanning angle (α) in a range of 70° to 110°. The propulsion system comprises a plurality of propellers with motors configured for flight without wings, including static hovering flight, the VTOL UAV comprising a yaw axis (Z) about which it can rotate upon itself. The 3D LIDAR sensor is statically mounted on the chassis such that the LIDAR laser beam 360° rotation axis (R) is inclined at a LIDAR inclination angle (β) with respect to the yaw axis (Z) in a range of 35° to 50°.

The invention discloses an indoor toxic and harmful gas three-dimensional imaging and tracing method and equipment, and the method comprises the steps: placing remote measurement instruments based on a laser detection principle at different corners in a room, obtaining the remote measurement data of each space layer at different scanning angles, and positioning a gas concentration high-value region; dense point locations are arranged in a gas concentration high-value area of each spatial layer, an in-situ measurement instrument based on a spectrum detection principle is utilized to measure and obtain in-situ data on the point locations, and meanwhile, extremely-high-resolution poisonous and harmful gas accurate traceability is realized; the two-dimensional distribution of the gas concentration of each space layer is obtained through remote measurement and in-situ data reconstruction, and is further mapped to a three-dimensional space to realize three-dimensional imaging and gas traceability. A wide-area light beam scattering gas telemetering instrument and a multi-pass reflection ultra-sensitive gas in-situ measuring instrument are autonomously designed, so that full-space rapid three-dimensional imaging and accurate traceability can be realized, system errors are reduced, an extremely low detection limit is achieved, and the feasibility, accuracy and high efficiency of the method are ensured.

The present invention relates to the field of high-rate mobile wireless communications. Disclosed are a multi-frequency multi-polarized wide-beam scanning base station system, and an optimization design method. The method comprises: on the basis of an aperture field expansion theory and a mode coupling theory, designing a conical horn feed source antenna capable of radiating a Gaussian fundamental mode beam, and providing a stable beam width and a stable phase center; designing a beam separation device based on a periodic structure, wherein the beam separation device includes band-pass frequency selective surfaces and a linear polarization grid; and combining front-end quasi-optical links of multiple frequency channels and multiple polarized channels, so as to increase the bandwidth and communication rate of a base station antenna. In the present invention, a genetic optimization algorithm is combined with reflector shaping, thereby effectively reducing the conflict between a shielding effect of a dual-reflector antenna and a scanning angle, and realizing the multiplication of a beam scanning angle.

The disclosure relates to radio engineering, and more specifically, to a wide scan angle antenna array. Technical result consists in expanding the scanning range, increasing the efficiency of the antenna array and reducing losses. Antenna array is provided. The antenna array includes a plurality of antenna array elements, and a metasurface disposed above the antenna array, wherein the metasurface is a dielectric layer having, on a first side thereof, conductive elements configured to reflect part of radiation of the antenna array; the distance between the antenna array and the metasurface is based on an integer number of half wavelengths, an operating wavelength of the antenna array in a medium in the space between the antenna array and the metasurface, and a predetermined scanning angle of the antenna array.

An apparatus for performing laser cutting and collection of a target micro-region of a tissue section on a blade. The apparatus comprises a carrier stage, a blade, a laser cutting system, a control module and a collector, wherein the laser cutting system comprises a laser device, a beam expander, a galvanometer scanner and an objective lens; and by means of adjusting a scanning angle θ of the galvanometer scanner and combining same with the objective lens, a scanned laser is focused to realize the cutting of a target micro-region on a tissue section and the ejection of the target micro-region. Laser microdissection is combined with mechanical sectioning, and non-contact collection of a specific micro-region of a tissue section placed on an inclined blade is achieved under the action of laser edge ejection combined with a dielectrophoretic force, such that the integrity of the morphology of a sample throughout an acquisition process is ensured, three-dimensional positional information of a target cell or cell population is accurately reserved, the cutting efficiency is improved, and non-contact cutting can also be realized to prevent the sample from being contaminated.

The invention provides an MEMS (Micro Electro Mechanical System) micromirror array chip, a module and optical scanning equipment. The MEMS micromirror array chip comprises a plurality of micromirror structures, a substrate, a vertical lead structure and a capacitance angle sensing structure, according to the micro-mirror array chip integrated with the capacitive sensor, array-level real-time angle detection, feedback control and high-precision scanning angle detection are realized, and the micro-mirror array chip is fast in driving and resistant to interference; meanwhile, the wiring density is reduced by frequency division multiplexing isolation signals; in addition, the application of a monolithic integrated capacitance angle sensor in a high-density micro-mirror array chip is realized by a thick substrate with a silicon through hole; and finally, the micromirror array chip of the monolithic integrated capacitance angle sensor is used for precision optical scanning equipment, a photoelectric angle detector is omitted, optical scanning high-precision real-time angle detection and feedback control, high-precision angle detection and high-speed scanning are realized, the use design is convenient, and the cost is low.

The invention discloses a multi-scanning-angle parallel phase calibration method for a waveguide grating antenna, and the method comprises the steps: receiving light emitted by a one-dimensional waveguide grating antenna with M units through a receiving screen disposed in a far field, and shooting a far-field image through a camera; n detection points # imgabs0 # with different scanning angles are arranged on the far-field image; any unit m of the one-dimensional waveguide grating antenna is selected as a control object, the phase of emergent light of the unit m is changed from 0 to 2 pi by the control voltage with the step length of # imgabs1 #, and the corresponding control voltage when the energy of a detection point # imgabs2 # at different scanning angles reaches the maximum value serves as the calibration voltage # imgabs3 # of the grating antenna unit m at different scanning angles. According to the method, parallel calibration of control voltages at different scanning angles of the waveguide grating antennas is realized in a mode of circularly applying voltages to each waveguide grating antenna, and the calibration efficiency of the phases of the waveguide grating antennas is greatly improved.

The invention discloses a circularly polarized wide-angle scanning phased-array antenna, which comprises a plurality of quaternary sub-arrays, each quaternary sub-array comprises four antenna units, the feed phases of the four antenna units are sequentially subjected to 90-degree phase compensation to form the quaternary sub-array, and the plurality of quaternary sub-arrays are sequentially combined to form the phased-array antenna. A metamaterial wide-scanning matching structure is loaded above an antenna array plane, a double-layer structure is adopted, correction is improved through phase compensation, the phased-array antenna has the large-angle scanning capacity of + / -70 degrees, and the axial ratio at the center frequency point 29.5 GHz and at each scanning angle is smaller than 1.5 dB. The invention provides the circularly polarized wide-angle scanning phased-array antenna, the phased-array antenna has the large-angle scanning capability of + / -70 degrees, the axial ratio in the scanning range is within 3dB, and the circularly polarized standard can still be met.

The present disclosure is applicable to a field of laser radar technology and provides a resonance module, a silicon-based external cavity chip, a laser, and a laser radar. The resonance module includes multiple main resonators and at least one auxiliary resonator, both of the main resonators and the auxiliary resonator are tunable micro-ring resonators; the multiple main resonators are cascaded in sequence through a connecting module to form a cascaded structure, and a vernier effect can be formed between two adjacent main resonators; when an auxiliary resonator is provided for matching the main resonator, coupling of the main resonator and the auxiliary resonator that are provided in a matching manner expands a free spectrum range of the main resonator. The tunable range of lasers applied to the laser radar and improve the scanning angle of the laser radar can be expanded.

The invention relates to the technical field of surveying and mapping remote sensing, and discloses a sparse airborne laser radar data single tree identification method based on a Transform network, and the method comprises the following steps: S1, collecting airborne laser radar point cloud data of a forest; s2, preprocessing the laser point cloud data to obtain a single tree instance point cloud data sample; and S3, constructing a double-branch Transform network, training the model by using the training set, selecting an optimal model, and testing. According to the method, a Transformer model of a double-branch structure is designed to process geometric information corresponding to three-dimensional coordinate information of point cloud data and other attribute information such as a scanning angle, an echo number and echo intensity so as to obtain a high-precision classification result.

A half-spectrum search DOA estimation method based on characteristic value gradient jump belongs to the field of array signal processing, and comprises the following steps: modeling a received signal to obtain an array output vector; calculating a received signal covariance matrix; introducing a complex conjugate covariance matrix and a scanning source to construct a new covariance matrix, and constructing a spatial spectrum function; constructing a characteristic value gradient discrimination function, and adaptively estimating a signal source number by using the characteristic value gradient discrimination function; scanning angles are traversed by using a half-spectrum search method, and a signal direction of arrival is verified and determined by combining an MVDR algorithm according to a sharp spectrum peak formed by a spatial spectrum function. According to the method, source number priori knowledge is not needed, the source number can be identified autonomously, the problem that estimation is inaccurate under complex conditions in traditional half-spectrum search is solved, and the method has good robustness under the scene of unknown source number. According to the method, the limitation that few traditional half-spectrum search angle estimation is inaccurate is overcome, and a new thought is provided for half-spectrum search DOA estimation under the condition that the number of information sources is unknown.

The present disclosure is related to improving image quality in a scanning camera system via scan angle selection to obtain images having overlap for performing image stitching, dynamically tuning an aperture of a camera in the scanning camera system, updating pixel values of an image using vignetting data, or a combination thereof.

The invention provides a vehicle railway slab detection method based on a laser radar, and the method comprises the steps: obtaining two-dimensional point cloud data of a railway slab sensed by the laser radar, wherein the two-dimensional point cloud data comprises a plurality of pieces of two-dimensional point data; determining the two-dimensional point data of which the scanning angle is a preset angle as an orthographic projection point, and traversing the two-dimensional point cloud data from the orthographic projection point according to an angle difference value of the scanning angles between the adjacent two-dimensional point data, and if the difference value of the scanning distances between the adjacent two-dimensional point data is greater than a distance threshold value, traversing the two-dimensional point cloud data from the orthographic projection point; and determining the two-dimensional point data corresponding to the smaller scanning distance in the adjacent two-dimensional point data as a first edge point and a second edge point of the railway slab. And based on a trigonometric function, determining a first distance between the first edge point and the orthographic projection point and a second distance between the second edge point and the orthographic projection point according to the scanning distance and the scanning angle of the first edge point and the second edge point. And detecting whether the vehicle deviates from the center of the railway slab according to the first distance and the second distance.

The invention relates to the technical field of gas leakage detection and optical remote sensing, particularly discloses a laser natural gas leakage point positioning and imaging processing method based on an unmanned aerial vehicle, and aims to solve the problems of multiple coverage blind areas, low positioning precision and easiness in environmental interference in the prior art. The method comprises the following steps: acquiring a methane concentration integral value through a tunable diode laser absorption spectrum system carried by an unmanned aerial vehicle; constructing an initial concentration point cloud in combination with the high-precision pose and scanning angle data; performing space-time filtering and interpolation enhancement by adopting Kalman filtering and a Gaussian plume model to generate a high-confidence three-dimensional concentration field; and accurately positioning a leakage source by using a gradient rising tracking algorithm in combination with curvature and continuity constraints, and matching pipe network geographic information to perform verification alarm. According to the technical scheme, large-range, high-precision and full-automatic natural gas leakage detection and visual positioning are realized, and the signal-to-noise ratio, the anti-interference capability and the response efficiency are remarkably improved.

The present disclosure is related to improving image quality in a scanning camera system via scan angle selection to obtain images having overlap for performing image stitching, dynamically tuning an aperture of a camera in the scanning camera system, updating pixel values of an image using vignetting data, or a combination thereof.

An ophthalmic device including an interference optical system that detects interference light between signal light obtained by scanning an examined eye with light from a light source and reference light configured from light divided from the light source, an adjustment section that is disposed on an optical path of at least one out of the signal light or the reference light, and that adjusts a polarization state of light propagating along the at least one optical path such that a polarization state of the signal light is the same as the polarization state of the reference light, and a control section that controls the adjustment section according to a scan angle scanned on the examined eye.

The invention discloses a self-adaptive wave position design method for a high-orbit SAR (Synthetic Aperture Radar). The self-adaptive wave position design method comprises the following steps: step 1, determining an imaging mode, a wave position, a polarization mode, a satellite position at a current orbit moment, a satellite attitude, an antenna installation azimuth angle, an antenna installation pitch angle and an antenna imaging wave position scanning angle; step 2, according to the imaging mode, determining a transmitting pulse width, and setting a maximum duty ratio and a minimum duty ratio; 3, determining the maximum available PRF, the image fuzziness and the system sensitivity at the current orbit moment according to the maximum duty ratio and the minimum duty ratio; 4, determining whether to update the PRF according to the image ambiguity and the system sensitivity; step 5, calculating to obtain radar echo starting time and echo window length; and step 6, returning to the step 1 at the moment of entering the next track. According to the method, different PRFs can be adaptively selected according to different track positions, so that adaptive adjustment of radar parameters is realized.

The invention provides a rapid three-dimensional ultrasonic imaging system, imaging method and device. The rapid three-dimensional ultrasonic imaging system comprises an ultrasonic transduction unit group arranged in a bearing body; the ultrasonic transduction units in the ultrasonic transduction unit group are arranged in a twisted manner, so that the ultrasonic transduction units are arranged in a staggered manner along a set direction to obtain a larger scanning range; the control end sends out a working instruction, and at least two ultrasonic transduction units in the ultrasonic transduction unit group are periodically selected to scan the target area; in any period of scanning the target area by the ultrasonic transduction unit, adjusting the scanning angle of the ultrasonic transduction unit at least twice to obtain local image data; the control end acquires local image data, performs data interaction with the reconstruction end in a parallel / serial mode, and is used for quickly acquiring a three-dimensional ultrasonic image for a target area; the three-dimensional imaging system is smaller in data volume, shorter in imaging time and higher in efficiency.

The present disclosure is directed to a camera configured to capture a set of oblique images along a scan path on an object area; a scanning mirror structure including at least one surface for receiving light from the object area, the at least one surface having at least one first mirror portion at least one second portion comprised of low reflective material arranged around a periphery of the first mirror portion, the low reflective material being less reflective than the first mirror portion; and a drive coupled to the scanning mirror structure and configured to rotate the scanning mirror structure about a rotation axis based on a scan angle. The at least one second portion can be configured to block light that would pass around the first mirror portion and be received by the camera at scan angles beyond the set of scan angles.

A peak two-dimensional detection data extraction unit (211) extracts two-dimensional detection data (peak two-dimensional detection data) of a diffracted X-ray (Xb) having the highest X-ray intensity from two-dimensional detection data of diffracted X-rays (Xb) obtained at a plurality of scanning angles (2 [theta] / [theta]). Next, a peak position specifying unit (212) specifies a position at which the X-ray intensity is maximum (peak position) on the basis of the two-dimensional peak detection data. Then, data processing is performed using position information on the peak position determined by the peak two-dimensional detection data.

The invention discloses a tunnel segment scanning platform and a tunnel segment scanning method, and relates to the technical field of tunnel segment scanning, the tunnel segment scanning platform comprises a frame, a bracket, a moving assembly, a scanning assembly and a detection piece, and the frame defines a scanning area; the bracket is arranged in the scanning area, and the bracket can support the duct piece in a lifting mode; the moving assembly is movably connected to the top of the frame; the scanning assembly is installed on the moving assembly and comprises a connecting framework, a scanner and a plurality of target balls, the connecting framework is hollow, the scanner is arranged in the connecting framework, the target balls are arranged on the connecting framework at intervals, reflection points are arranged on the target balls, and the scanner is used for scanning segments; the detection part is used for obtaining the position and posture of each target ball. A final model is obtained by fitting a plurality of scanning models of the duct piece at different height positions, the influence of different scanning angles and different ambient light on a scanning result is eliminated as far as possible, and the scanning precision is effectively improved.

A beamforming transmission system and a method of controlling an output power of a beamforming transmission system are disclosed, the system comprising one or more transmission elements, the one or more transmission elements each comprising a power amplifier; an antenna coupled to the power amplifier; and a power detector coupled to the antenna; a power controller coupled to the power amplifier; a system processing module coupled to the one or more transmission elements, the system processing module further coupled to the power controller, the system processing module being arranged to instruct the power controller to control an output power of the power amplifier; wherein the system processing module is arranged to determine a desired beam scanning angle of the one or more transmission elements and to obtain a present output power of the power amplifier from the power detector; and further wherein the system processing module is arranged to instruct the power controller to control the output power of the power amplifier based on both the desired beam scanning angle and the present output power of the power amplifier.

The invention provides an information processing method and device of a phased array and electronic equipment. The information processing method comprises the following steps: determining an actual beam width and maximum sidelobe information according to a target directional diagram of a phased array of a target beam at a target scanning angle; wherein the target directional diagram is determined according to the on-off state of a target array element in the phased array; calculating a corresponding target value according to the deviation between the target beam width and the actual beam width and the maximum sidelobe information; determining an optimal target value in a plurality of target values corresponding to different switching states of the target array element; and determining the on-off state of each array element of the target wave beam at the target scanning angle according to the on-off state of the target array element corresponding to the optimal target value. According to the invention, constraints are applied to the beam width and the maximum sidelobe information of the beam, so that the interference level between same-frequency beams can be reduced essentially.