3827 results about "Azimuth" patented technology

The invention relates to the technical field of communication, in particular to an airborne Tiantong phased-array antenna and an application method thereof. According to the method, phased-array antenna beams are driven to perform electronic scanning according to a geometric azimuth angle, beacon signal blind acquisition is performed in a preset airspace in a wide beam mode, and when an initial signal is detected, the mode is immediately switched to a narrow beam scanning mode; dynamically adjusting a phase weighting coefficient to realize pointing adjustment, so that a signal quality parameter is continuously converged in an optimal threshold interval; carrying aircraft maneuvering acceleration feedback is introduced, beam pointing offset is dynamically compensated based on a pre-constructed interference feature library, and signal fluctuation caused by a multipath effect is suppressed; and continuously checking a data validity flag bit of the main inertial navigation system, seamlessly switching to an antenna built-in inertial navigation data stream when a failure threshold is triggered, and activating a rapid recapture program to maintain zero interruption of a communication link. Through dual-source inertial navigation data fusion and intelligent beam control, rapid and accurate tracking of Tiantong satellites in an airborne environment is realized.

The invention relates to the technical field of directional drilling track control, and discloses a coal mining underground directional drilling track control method and system, and the method comprises the steps: carrying out the fusion track analysis of a drilling machine based on sensor data, drilling parameters and pre-obtained geological hardness parameters, and obtaining a reference track of the drilling machine, a sensor, an azimuth angle sensor and a bit pressure sensor are used for synchronously collecting drill bit attitude data of a drilling machine to generate a real-time track of the drilling machine, then track offset calculation is carried out to obtain inclination angle deviation and azimuth angle deviation, and dynamic gain adjustment analysis is carried out on the drilling machine to obtain adjustment parameters of the drilling machine. And finally, the drill bit posture of the drilling machine is adjusted based on the adjusting parameters. According to the method, the directional control accuracy of the underground drilling track can be improved.

The invention belongs to the technical field of geophysical monitoring, and relates to an electromagnetic interference detection method for earthquake monitoring, which comprises the following steps: deploying a multi-dimensional electromagnetic field sensing unit and an earthquake signal acquisition unit and realizing high-precision synchronization; synchronously acquiring multi-dimensional electromagnetic field and seismic physical signal data; performing multi-feature and noise feature extraction on the two; inputting the features into a pre-trained machine learning / deep learning model for identification, and outputting information such as interference type, intensity and azimuth angle; and carrying out influence evaluation and quality marking on the seismic data according to the output, and selectively inhibiting or compensating. Through the above scheme, multi-dimensional perception and characterization, high-precision synchronization and correlation analysis, intelligent identification and spatial positioning are realized, and the reliability and accuracy of earthquake monitoring data are significantly improved.

The invention discloses an unmanned ship displacement attitude high-precision fusion method based on adaptive Kalman filtering, and belongs to the technical field of ship sensing positioning, and the method comprises the steps: building a discrete time state space model of a navigation data state through employing a discrete integration mode based on the navigation data state; obtaining a system state equation by means of a rotation matrix and a median theorem; obtaining an observation transfer matrix through coordinate system information, a geodesic line length between two points and an azimuth angle, and obtaining a state observation equation by combining noise data; based on the system state equation and the state observation equation, using an adaptive Kalman filtering algorithm to obtain displacement attitude information of the unmanned ship; detecting the prediction data of the unmanned ship by using a sliding window method; and when the predicted data is detected to be abnormal, substituting the predicted data into Kalman filtering for correction. According to the invention, through state modeling, fusion algorithm, anomaly detection and anomaly correction, the precision, reliability and robustness of obtaining the displacement attitude information of the unmanned ship are improved.

The invention relates to the technical field of optical detection, in particular to an aspheric lens laser interference detection adjustment error separation system and method, and the method comprises the steps: placing an aspheric lens on a clamping platform, carrying out the multiple laser interference measurement through adjusting different pitch angles and azimuth angles, and collecting a multi-angle interference fringe image; for different installation and adjustment error types, key features of typical error fringe images are extracted and compared with current interference fringe images, and identification of the installation and adjustment error types and levels is achieved; a mathematical model of various installation and adjustment errors is constructed, polynomial parameterization representation is adopted, installation and adjustment compensation parameters are reversely solved according to an identification result, and installation and adjustment are completed; and repeating the measurement and analysis process, and constructing an error adjustment frequency optimization model until the precision requirement is met. The method provided by the invention can improve the adjustment efficiency and precision of the aspherical lens.

The invention discloses a high-feature-resolution underwater weak target parameter estimation method based on NOMP, and the method comprises the steps: obtaining a receiving array signal, carrying out the preprocessing of the receiving array signal, carrying out the azimuth angle estimation through employing a conventional beam forming algorithm, and extracting a beam output signal in a main target direction; rough search is carried out on discrete time delay and Doppler factor grids, initial parameters of a current most significant path are estimated, continuous optimization is carried out through a Newton iteration method, and optimized path parameters are obtained; constructing a continuous path echo signal according to the received signal, deducting the contribution of the current path to the received signal from the received signal, updating a residual signal, and continuously searching the next path by taking the residual signal as a new input signal until an iteration termination condition is met; and outputting parameter estimation results of all paths. According to the method, high-precision and high-resolution extraction of weak target parameters can be realized in an environment with a low signal-to-noise ratio and remarkable underwater multipath interference.

Techniques for detecting radar data inaccuracies using a multistage filtering technique are discussed herein. A vehicle may capture radar data including a set of radar points. The vehicle can input the radar data into a machine-learning model configured to detect objects and / or generate bounding boxes associated with such detected objects. In some instances, the vehicle may cluster the radar points such that a cluster includes the radar points located proximate to and / or within a bounding box. To identify double bounce object detections, the vehicle may determine whether a detected object is a false-positive double bounce object detection based on evaluating the azimuth, range, and relative velocity double bounce criteria. Based on the detected object satisfying the double bounce criteria for azimuth, range, and relative velocity, the vehicle may modify the radar data.

The invention relates to the technical field of signal analysis, in particular to a GNSS (Global Navigation Satellite System) detection method and system based on machine learning, and the method comprises the steps: receiving a navigation radio-frequency signal containing reality and deception, and carrying out the down-conversion of an RF (Radio Frequency) front end to obtain intermediate-frequency data; gNSS signal capture is completed by searching correlation peaks in frequency and code phases based on intermediate frequency data; in the capturing stage, a motion state, a correlation peak number, a noise value, capturing parameters and peak + / -1 chip sampling features are extracted and input into a machine learning classification model to judge whether cheating exists or not; if so, separating the deception signal from the real signal, and respectively sending the deception signal and the real signal into independent tracking channels; measuring an array element carrier relative phase by an array antenna, establishing a phase center model, and correcting to obtain an effective phase center and a differential baseline; according to the method, a deception azimuth angle and a pitch angle are obtained, a beam weight is calculated, a deception direction is subjected to null setting, a real direction is subjected to main lobe protection, and a weight value is fed back in real time to improve a signal carrier-to-noise ratio and locking stability. According to the invention, the problem that the existing commercial GNSS signal is low in power and easy to be interfered by deception is solved.

The invention relates to the technical field of environmental shadow analysis, and discloses an environmental shadow analysis method for photovoltaic power station design, which comprises the following steps: collecting and preprocessing geographic space data of a photovoltaic power station; calculating a solar altitude angle and an azimuth angle based on the pre-processed parameters, and generating a three-dimensional solar direction vector; analyzing the geometric surface of the three-dimensional obstacle model, screening a visible surface patch according to a sun direction vector, and sampling effective projection points; dynamically updating the sun direction vector in a specified time period, and calculating shadow coordinates of projection points on the ground or an inclined plane in each time period; and generating shadow contours of all time periods and combining the shadow contours into a complete influence area. According to the invention, through the dynamic sun trajectory modeling and complex obstacle surface analysis technology and in combination with the multi-modal projection correction and Boolean operation merging strategy, high-precision analysis of shadow spatial-temporal distribution in a complex environment, multi-installation scene self-adaption and dynamic shielding influence quantitative evaluation are realized.

The invention discloses a wireless optical communication alignment system and a capture alignment method thereof, and relates to the technical field of optical communication, and the method comprises the steps: a three-dimensional holder carries out the coarse alignment of an optical path between a transmitting end and a receiving end according to the direction of beacon light; an alignment device located at the top of the three-dimensional holder carries out fine alignment on the light path; the alignment device comprises a two-dimensional alignment structure, a control circuit and a device shell. The control circuit captures a light intensity feedback value of the light intensity sensor of the two-dimensional alignment structure, and adjusts an azimuth angle and a pitch angle of the optical fiber collimator of the two-dimensional alignment structure according to the light intensity feedback value so as to adjust lens orientations of the transmitting end and the receiving end; the device shell provides a supporting platform for the two-dimensional alignment structure and the control circuit and is connected with the three-dimensional holder. Coarse alignment and fine alignment are combined, accurate angle adjustment is achieved through light intensity feedback, efficient alignment of light paths of the transmitting end and the receiving end is ensured, meanwhile, the device shell provides stable support and connection, and the stability and reliability of the alignment process are guaranteed.

The invention relates to the technical field of unmanned aerial vehicle communication anti-interference, in particular to an unmanned aerial vehicle anti-interference system based on spectrum sensing. According to the invention, a spectrum sensing data acquisition module acquires multi-band frequency spectrum signal data and generates a spectrum interference characteristic spectrum; the interference source positioning module calculates an azimuth angle and a distance of an interference source and generates a spatial distribution data set; the three-dimensional interference field construction module constructs a three-dimensional interference field model containing an interference intensity gradient and a propagation direction in combination with the real-time height and geographic coordinates of the unmanned aerial vehicle; the anti-interference strategy generation module analyzes the vulnerability of a communication link, and dynamically adjusts the frequency band switching priority and the transmitting power allocation weight; the beam forming control module calculates antenna array phase offset and a beam pointing angle, and generates an adaptive beam forming parameter set. The system can improve the anti-interference capability and communication stability of the unmanned aerial vehicle in a complex electromagnetic environment.

The invention discloses a phased array receiving beam resource allocation method for satellite communication, which relates to the technical field of satellite communication, and comprises the following steps: acquiring satellite position, user position and satellite attitude data, calculating an azimuth angle and a pitch angle of a propagation path, querying a pre-stored dark matter density distribution database of a satellite-borne memory, and calculating a pre-stored dark matter density distribution database of the satellite-borne memory; extracting a dark substance density value; according to the user service priority and the real-time channel quality, a beam resource proportion is adjusted in a resource allocation table, and a beam scheduling instruction is generated; and executing the beam scheduling instruction, driving the state switching of the millimeter wave phased array phase shifter, monitoring the change rate of the signal-to-noise ratio of the user terminal, and re-calculating the azimuth angle and the pitch angle of the propagation path when the continuous change rate of the signal-to-noise ratio exceeds a preset change rate threshold. According to the method, a space-borne pre-stored dark matter density database is inquired, a phase disturbance value is calculated, and the cosmic scale dark matter physical field effect is brought into a beam control closed loop.

The invention discloses a self-stabilization control photoelectric tracking rotary table and method based on a rate gyroscope. The method comprises the following steps: respectively acquiring an azimuth compensation angular velocity and a pitching compensation angular velocity of the photoelectric tracking rotary table under a rotary table coordinate system and a roll angular velocity interference variable of the photoelectric tracking rotary table under a platform coordinate system through the rate gyroscope; constructing a rotation matrix, converting the roll angular velocity interference variable of the photoelectric tracking rotary table under the platform coordinate system into the roll angular velocity interference variable of the photoelectric tracking rotary table under the rotary table coordinate system, and performing Kalman filtering processing to obtain the optimal estimated angular velocity of the photoelectric tracking rotary table; and obtaining the control quantity of the photoelectric tracking turntable according to the optimal estimated angular velocity, and adjusting the control voltage of the photoelectric tracking turntable. According to the method, the process noise covariance matrix and the observation noise covariance matrix are updated by using the adaptive noise covariance matrix, so that the problem of filtering divergence or estimation lag caused by the fact that Kalman filtering adopting fixed noise covariance parameters is difficult to adapt to a dynamic environment is avoided.

The invention discloses a fan blade safety monitoring device, solves the problem that the measurement precision of the azimuth angle and the distance of a blade tip is limited to a certain extent due to weak reflection echo of a millimeter wave radar, and belongs to the technical field of safety monitoring and intelligent detection of new energy equipment. The system comprises an antenna, a passive electronic tag and a main control module. The passive electronic tag is attached to a to-be-monitored part of a fan blade and is used for reflecting the modulated electromagnetic wave signal after receiving the modulated electromagnetic wave signal; the antenna transmits a modulation electromagnetic wave signal to the passive electronic tag, and is also used for receiving a modulation signal reflected by the passive electronic tag and transmitting the modulation signal to the main control module; and the main control module controls the antenna to send a modulation electromagnetic wave signal, calculates a clearance distance and / or a vibration characteristic parameter in combination with a modulation signal reflected by the passive electronic tag, and carries out safety monitoring on the fan blade according to the clearance distance and / or the vibration characteristic parameter. An annular array millimeter wave radar can be selected as the antenna. According to the invention, the fan blade can be accurately monitored.

An optical detector system providing electrical output signals. The system includes an apertured surface and a transparent window, with a metasurface on the window's opposite side. The metasurface imparts spatially varying phase delay and / or amplitude or polarization modulation to deflect ILR based on their angle of incidence, producing exiting light rays. These rays are detected by a two-dimensional tetralateral position-sensing detector (TLD) with a single resistive photo-absorption layer and four electrodes. The TLD generates X-Y position signals proportional to the azimuth and elevation of the incoming ILR. A computer may be included to calculate these angular values from the position signals.

The invention discloses a ship-based radar and AIS data fusion method and device based on the satellite internet, and relates to the technical field of ship information. The method comprises the following steps: acquiring self-motion, AIS and radar data recorded by a plurality of ships in real time through a low-orbit satellite, and performing target trajectory tracking and data filtering by adopting a first-order linear ship motion model and a self-adaptive extended Kalman filter; the method comprises the following steps: establishing an error model containing a radial error coefficient, an azimuth angle error and an effective detection distance for dynamic system errors of a shipborne radar, and realizing radar-AIS target matching and error correction based on an adaptive differential evolution algorithm and a Hungary algorithm; and finally, performing fusion processing on unknown targets sensed by multiple nodes through a multi-hypothesis tracking method to form a globally unified target observation result. According to the method, shipborne radar data and AIS data can be effectively associated, real-time monitoring of ship targets in a wide-area sea area is achieved, and reliable technical support is provided for marine supervision, safety early warning and track backtracking.

The invention relates to the technical field of image data processing, in particular to an urban building three-dimensional reconstruction method and device, and the method comprises the steps: obtaining a multi-view satellite orthoimage from the same scene, satellite-borne laser height measurement data of a target region, a digital terrain model and two-dimensional building vector data; performing accurate geometric registration on the multi-view satellite orthoimage, and executing dense matching to generate an initial parallax point cloud; and combining azimuth angle information of the multi-view orthoimage to construct a disparity map with accurate plane positioning. And calculating an elevation value above the earth surface by using satellite-borne laser altimetry data and a digital terrain model. And jointly estimating a parallax elevation proportionality coefficient by using the elevation value and the parallax value so as to convert the parallax map into a height map. And generating three-dimensional building vector data of the target area in combination with the two-dimensional building vector data. Therefore, the problems that cost based on surveying and mapping level remote sensing data is high, data collection is limited, and the requirement for global city three-dimensional reconstruction cannot be met in the prior art are solved.

The invention discloses a polarization spectrum modulation type multispectral stereo imaging method which solves the problem that in the prior art, an existing polarization spectrum imaging scheme does not achieve three-dimensional reconstruction of a target and achieves the purpose that the three-dimensional reconstruction of the target is not achieved under the condition that active illumination or special marks are not needed. Synchronous high-precision reconstruction of physical attributes and three-dimensional geometry of the surface of the target is realized; the method comprises the following steps: uniformly modulating polarization information and spectral information of incident light of a target through a three-way optical filter and a polaroid to obtain modulated incident light information; performing aliasing acquisition of a plurality of polarization spectrum components on the modulated incident light information through a multi-color detector combination to obtain aliasing light intensity; performing linear solution on the aliasing light intensity to obtain each polarization spectrum component vector, calculating the polarization degree and the polarization angle of each channel, and further deriving a surface zenith angle and an azimuth angle; reconstructing the three-dimensional morphology of each spectrum channel through normal gradient field frequency domain integration; and finally, fusing the multi-spectral three-dimensional data to obtain a multi-spectral three-dimensional imaging result.

The invention discloses an acoustic Doppler flow velocity measurement method and system, and the method comprises the steps: generating an emission parameter combination adaptive to a current hydrological environment according to the depth characteristics and precision requirements of a target water area; original echo signals are collected based on the emission parameter combination, and a three-dimensional flow velocity vector of temperature compensation is output; inputting the three-dimensional flow velocity vector into the dynamic segmentation network to generate a layered flow velocity distribution model; calling a layered flow velocity distribution model, fusing fluxgate compass azimuth data to carry out flow direction compensation, triggering a deviation correction algorithm when equipment inclination exceeds a limit, and outputting absolute flow velocity distribution of pose calibration; and according to absolute flow velocity distribution and echo intensity dynamic range constraint, calculating an error interval of each depth unit, and outputting a final flow velocity profile with confidence identification. According to the embodiment of the invention, the environmental adaptability and data reliability of flow velocity measurement can be improved.

The invention relates to the technical field of man-machine interaction, in particular to a multi-user-based ring pairing and left and right hand judgment method and system and a medium, and the method comprises the steps: firstly collecting azimuth angles, distances and historical tracks of a plurality of rings, and clustering the azimuth angles, the distances and the historical tracks into different user clusters; shoulder breadth geometric constraint, posture consistency, micro-motion synchronism and historical prior are fused in the cluster, paired scores are calculated, and paired rings are identified by using a greedy strategy; and then, calculating a judgment score to distinguish the left hand and the right hand by counting the rotation deviation of the angular velocity of the gyroscope on the horizontal plane projection and combining the spatial position score of the ring relative to the human body center line with the historical consistency. A steady-state mode and an event-driven wake-up mechanism are also introduced to balance power consumption. According to the invention, through multi-modal fusion, automatic ring pairing and accurate left and right hand judgment are realized.

The invention discloses a ship dynamic collision avoidance decision-making method based on an improved DWA algorithm. The ship dynamic collision avoidance decision-making method comprises the steps of constructing sea chart environment data containing obstacle density through a grid method; establishing a dynamic elliptical ship domain based on a quaternion ship domain (QSD) model, and calculating a distance collision risk degree (NCRI) between ships based on the dynamic elliptical ship domain; improving a DWA algorithm evaluation function, and adding a path yaw evaluation function and a collision avoidance rule evaluation function on the basis of optimizing a speed and azimuth angle evaluation function; fusing the multiple evaluation functions by adopting a weight distribution method; and finally, generating a local collision avoidance optimization route based on environment data, NCRI and an improved DWA algorithm. According to the method, safety boundary dynamic adjustment, rule compliance constraint and ship control characteristic cooperation are realized, and the robustness and practicability of collision avoidance decision making under complex sea conditions are remarkably improved.

The invention relates to the technical field of marine remote sensing observation, in particular to a squint ATI-SAR multi-view sub-aperture focusing marine vector flow inversion method. The method comprises the following steps of observation of strabismus ATI-SAR loads, focusing of multi-view sub-apertures, inversion of multi-view HLOS flow velocity, overdetermined equation solving of vector flow and checking of internal and external consistency of the vector flow. Non-side-looking observation is adopted for the load, observability of components in the rail direction is enhanced through physical squint, and low cost of a single beam and system conciseness are kept; according to the method, the contribution of the azimuth component is in direct proportion to the squint angle sine, so that the along-track component far greater than the virtual squint can be obtained, the solvability of the equation is improved, and the inversion instability is reduced; visual and reliable information observation is achieved with small system burden, equipment investment is saved, large-scale vector flow on-orbit observation can be achieved, and engineering is easy to achieve. According to the method, three-step closed-loop processing is carried out, the bottleneck of the traditional technology is solved, and the engineering availability and the result robustness are broken through.

The invention provides an unmanned aerial vehicle visual inspection and AIS data association method and device, and the method comprises the steps: carrying out the target detection of an image photographed by an airborne image sensor on an unmanned aerial vehicle in maritime cruise, obtaining the azimuth features of a ship in the image, and enabling the azimuth features to comprise the position information and the course information; according to a ship automatic identification system installed on each ship, acquiring AIS data of each ship; and matching the azimuth features of the ships in the image with the azimuth features in the AIS data of each ship, obtaining the AIS data corresponding to the image, and associating the image with the AIS data corresponding to the image. Visual inspection and AIS data association are realized, course information is additionally introduced on the basis of position feature matching, and the accuracy of visual inspection and AIS data association is improved.

The invention relates to the field of unmanned ship control, and provides a flight path tracking method, system and device based on an improved bee colony algorithm and a medium, and the method comprises the steps: determining the position information of an unmanned ship through a navigation device; obtaining an expression of a reference course angle through a predetermined path, calculating an azimuth error and a foresight distance, calculating a virtual input calculation direction error, and generating an initial rudder angle; interference parameters are obtained, a model attitude controller is established, the motion attitude of the unmanned ship is predicted, a path prediction error is obtained, and an optimization function is constructed; calculating a dynamic weight coefficient and an adaptive scaling factor, carrying out initial solution migration to obtain an initial migration solution, selecting a current optimal solution, carrying out migration on the initial migration solution to obtain a target migration solution, and carrying out optimal solution solving of an optimization function to obtain a target rudder angle; and controlling the unmanned ship so as to complete the control of the unmanned ship. According to the invention, accurate track tracking of the unmanned ship can be realized.

The invention relates to a sun meridian detection and course angle real-time calculation method based on polarized light field vector characteristics, and aims to solve the problems that a traditional sun meridian detection method is easily interfered in low signal-to-noise ratio scenes such as haze and cloud layer shielding, lens distortion causes polarization angle errors, the false detection rate is high, and the calculation accuracy is high. In order to solve the problems that the real-time performance and robustness of course calculation are affected due to the fact that single polarization angle information is difficult to fully reflect the sun direction, polarization parameter calculation is carried out by utilizing a multi-channel polarization image, and the sun meridian is detected by adopting Hough transform through fisheye lens correction, bilateral filtering and candidate region screening, so that the real-time performance and robustness of course calculation are improved. And a multi-point inversion method is combined to accurately obtain a sun vector and a zenith angle and an azimuth angle thereof, and finally a course angle is calculated in real time. The problems of imaging distortion and insufficient real-time processing in the traditional sun positioning technology can be effectively solved, and a powerful navigation positioning technical guarantee is provided for the fields of unmanned aerial vehicles, autonomous navigation, polarized light navigation and the like.

The invention relates to the technical field of bionic navigation orientation and positioning, in particular to a carrier course angle measuring method based on polarized light imaging in a non-Rayleigh atmosphere. Comprising the steps of real-time sky polarized light imaging, atmospheric polarization mode resolving based on Mueller matrix imaging, non-Rayleigh polarization information interference removal, polarization orientation resolving based on Rayleigh scattering, space projection conversion and sun position information resolving. Alignment information of the sun in a carrier coordinate system is obtained by utilizing a Rayleigh scattering model and actual sky polarization imaging, and then a carrier course angle is obtained according to the orientation of the sun in a local geographic coordinate system, so that an orientation function is realized; meanwhile, the error influence caused by image registration and time-sharing rotation measurement of the multi-view-field polarization detector and the interference of environmental factors on a single point are avoided, the method can adapt to sunny and cloudy weather, is also applicable to cloudy and other non-Rayleigh weather, and is wide in application range.

The invention discloses a three-dimensional conversion method for a two-dimensional geological profile map, and the method comprises the steps: S100, data obtaining and preprocessing: obtaining an original geological profile map, carrying out the format conversion of the original geological profile map, eliminating overlapped line segments and micro short line segments, and maintaining the topological consistency; s200, conversion parameter calculation is conducted, specifically, drilling coordinates are obtained, and a conversion script is compiled based on the real geodetic coordinates, the two-dimensional profile map coordinates and the azimuth angle; and S300, conversion execution: reading the map subjected to format conversion in the S100 into three-dimensional modeling software, and executing the script language compiled in the S200 to obtain a three-dimensional geological profile map. According to the method, the whole file is converted, the conversion from the two-dimensional geological prospecting line section to the three-dimensional geological section map can be rapidly and integrally completed through the existing software technology and simple script codes so as to be used for three-dimensional geological modeling, a large amount of manpower and material resources can be effectively saved, and the production efficiency can be improved.

The invention discloses an SAR image orientation sensitive target detection method based on sub-aperture image saturation characteristics, and belongs to the technical field of synthetic aperture radar image target detection. The azimuth sensitive target detection is realized through the following steps: 1) sub-aperture image generation: dividing an azimuth frequency spectrum into a plurality of sub-bands, and generating a plurality of sub-aperture images through inverse Fourier transform; 2) color synthesis and feature extraction: allocating different hues to each sub-aperture image by using an HSV color space, synthesizing an RGB color image, converting the RGB color image to the HSV color space, and extracting a saturation channel in the RGB color space as an azimuth sensitivity feature map; and 3) target detection: carrying out threshold segmentation on the saturation feature map, and identifying a pixel region with a high saturation value, namely, an orientation sensitive target. According to the method, the color saturation change caused by the scattering difference of the target in different sub-apertures is utilized, effective detection of azimuth sensitive targets such as artificial buildings and vehicles is achieved, and the method has the advantages of being simple in calculation and high in robustness.

The invention discloses a low-profile dual-circularly polarized wave beam scanning folding reflection array antenna. The low-profile dual-circularly polarized wave beam scanning folding reflective array antenna comprises a lower reflective array antenna and an upper circularly polarized selection metasurface. A circular polarization plane feed source is integrated in the middle of the reflective array antenna, and beam deflection is achieved. The circular polarization selection metasurface introduces opposite phase gradients to a left-hand circular polarization wave beam and a right-hand circular polarization wave beam through spin decoupling, and then introduces opposite wave beam deflection angles. Meanwhile, due to the polarization selection function of the circular polarization selection metasurface, the profile height of the antenna is half of the focal length of a traditional reflective array. By rotating the lower-layer reflective array antenna and the upper-layer circular polarization selection metasurface, the antenna can realize simultaneous + / -42-degree pitch angle scanning and 360-degree azimuth angle scanning of left-hand circular polarization and right-hand circular polarization dual beams, and the aperture efficiency, the axial ratio, the scanning loss and other performances are good. The low-profile dual-circularly-polarized wave beam scanning folding reflection array antenna provided by the invention can realize simultaneous scanning of two circularly-polarized wave beams, and is low in profile, compact in structure, low in cost and novel in function.

The invention discloses a pose estimation method and device based on air-ground cross-view image matching, and belongs to the technical field of image matching and positioning. According to the method, a global digital elevation model (DEM) and an orthographic image are generated by obtaining an aerial image sequence of a target area and are divided into a plurality of grids, and a multi-view-angle simulation forward view image is generated for each grid. After a visual sensor carried by a ground mobile platform obtains a ground front-view image, a simulation front-view image similar to the ground front-view image is screened by using a magnetic field azimuth angle, and an optimal grid is determined through feature point extraction and matching. And resolving a pose matrix of the ground mobile platform based on the feature point coordinates of the optimal grid, and further improving pose estimation precision through track reconstruction and optimization. According to the method, the problems of matching difficulty and low pose estimation precision caused by relatively large difference between imaging angles and imaging content scales of the aerial image and the ground front view image are effectively solved.