644 results about "Point target" patented technology

A weather radar system is coupled to antenna. The weather radar system includes a processor for generating pulses and for processing return pulses received by the antenna. The processor generates high resolution data from the return pulses. The processor uses the high resolution data to perform high resolution radar analysis including removal of point and/or point-like target returns and reassembles the high resolution data to perform high gain radar analysis at lower resolutions.

In one embodiment, a recovery manager may define a plurality of recovery target sets. Each recovery target set comprises a recovery point target, a recovery time target, and at least one other property. The recovery manager also defines a plurality of recovery classes. Each recovery class comprises at least one recovery target set of the plurality of recovery target sets. Each recovery class describes recovery requirements over an asset state life cycle. The recovery manager applies a first recovery class of the plurality of recovery classes to a first asset dependent on an importance of the first asset to an owner of the first asset. In some cases, the first recovery class and/or other recovery classes of the plurality of recovery classes may each be applied to multiple assets. In another embodiment, a recovery manager defines one or more recovery target sets to be applied to one or more assets and saves the one or more recovery target sets. In some embodiments, recovery classes are also saved.

The invention discloses an imaging method for a bistatic forward-looking synthetic aperture radar (SAR). Aiming at the defect existing when the existing method is used for the imaging process of the bistatic forward-looking synthetic aperture radar, the imaging method adopts a bistatic forward-looking SAR point target response two-dimensional frequency spectrum based on the least square polynomial fitting; the frequency spectrum is the least square approximation of the two-dimensional frequency spectrum with the accurate theory. According to the characteristics of bistatic forward-looking invariant SAR direction, variant range and nonlinear and variant Doppler centroid range of range cell migration in an RD (radar domain) domain, bistatic forward-looking SAR range migration correction, secondary-range compression and high-order phase compensation are realized by the frequency spectrum so as to accurately focus the bistatic forward-looking SAR. Compared with the traditional SAR imaging method and the bistatic forward-looking SAR imaging method, the method disclosed by the invention has higher imaging precision.

A means and method for enabling contact or touch point location detection to be implemented on a particular garment. This means and method simplifies the design of the garment by reducing the number of conductors required to interconnect the various touch points and signal processing circuitry; it provides a way to dynamically reposition or resize the effective touch point target regions; and it provides for new control capabilities by optionally allowing continuously variable user input control.

The invention discloses a stereoscopic vision optical tracking system aiming at multipoint targets, which belongs to the field of the mechanical vision and positioning tracking technique. The stereoscopic vision optical tracking system utilizes a mode based on hardware realization, utilizes a binocular camera to acquire targets and original images of the background, adopts a parallel pipeline to identify and mark the targets rapidly and utilizes a dual-core digital signal processor to perform parallel operation, and then space positioning and tracking of the target is completed. The parallel pipeline processing and the dual-core serial computing are combined, and then hardware resources are allocated reasonably according to different algorithm characteristics. The stereoscopic vision optical tracking system is free of constraint of a PC or working station and breaks through the bottleneck of software computing resources of the PC or working station. In addition, the system can perform real-time positioning and tracking on multipoint targets in space in different illumination environments with different target illumination strengths, and can real-time track over 100 point targets in space in a non-drop frame form. Tracking precision of the system can reach 0.5mm RMS.

The invention discloses a digital processing method of an altimeter of a linear frequency modulation continuous wave radar, which belongs to the field of the radio altimeters. The digital processing method comprises the following steps: step 1, obtaining beating signals from an orthogonal mixer arranged at the front end of the altimeter of the radar, and carrying out A/D (analog-to-digital) sampling to obtain a digital signal sequence; step 2, performing Fourier transform on the digital signal sequence, and calculating the amplitude of a spectral line; step 3, judging according to the amplitude of the spectral line of an amplitude spectrum, and measuring the beating frequency of the digital signal sequence; step 4, refining the frequency spectrum, calculating the slope correction of saw-tooth wave, and correcting the slope of the voltage signals of the saw-tooth wave; and step 5, calculating the high value of the current altimeter according to the slope of the voltage signals of the saw-tooth wave. The FFT-CZT method adopted by the invention is insensitive to noises and can perfectly work at lower signal-to-noise ratio, but the measurement precision is reduced. Because of having no limit on the properties of the targets, the digital processing method can be applied to the measurement and the analysis of point targets or surface targets.

The invention provides a simulator of a star sensor. The simulator comprises a collimating objective lens, wherein a focal plane of the collimating objective lens is provided with a star point target; the star point target is imaged at infinity through the collimating objective lens; a light splitting component is arranged between the collimating objective lens and the star point target; the focal plane of a light splitting optical path on the side face of the light splitting component is also provided with a detection target; the star point target is fixed on a focal plane adjusting mechanism; and a target lighting device is used for lighting the star point target. In the simulator, a technology which is different from the scheme of the conventional star simulator is adopted, so that the problem of poor accuracy of simulation of angular distance between stars of the conventional star simulator is solved; and the simulator can be used for extremely-high-accuracy simulation of a star and asteroid array of an asteroid autonomous navigation extremely-high-accuracy star sensor, verification of measurement accuracy and autonomous navigation and positioning accuracy of the star sensor, and has broad application prospect in research of a deep space autonomous navigation sensor.

A method and apparatus of predicting a crash are provided. The method includes detecting coordinates of a target obstacle based on first coordinate information of a radar sensor and second coordinate information of an ultrasonic sensor, translating the second coordinate information to the coordinate system of the first coordinate information and generating translated coordinate information, estimating a position, speed, and acceleration of a vehicle if the vehicle is a predetermined distance from the target obstacle based on the translated coordinate information, determining a potential crash type between the vehicle and the target obstacle based on the estimated position, speed and acceleration of the vehicle, determining a three-dimensional movement trajectory based on the estimated position, speed and acceleration of the vehicle and the determined crash type, and predicting a crash point of the vehicle, a crash point of the target object and a crash time based on the three-dimensional movement trajectory.

The invention discloses an SAR image nonlocal mean value speckle filtering method which belongs to the technical field of image processing, and mainly overcomes the problem of inaccurate distance computation of traditional SAR image nonlocal mean value speckle filtering similar blocks. The method comprises the following realization processes: 1. firstly judging whether a pixel point of an input SAR image is a point target, if so, keeping the gray value of the point target, otherwise performing the next step; 2. computing the distance between the pixel point and all pixel points in a search field according to a new distance measurement; 3. computing the weight values of all the pixel points in the search field according to the computed distance of all the pixel points in the search field; 4. carrying out weighted averaging for all the pixel points in the search field according to the computed weight values of all the pixel points in the search field to obtain the modified gray value of the pixel point; and 5. replacing the gray value of all points in the original SAR image with the modified gray value to obtain the speckle filtered SAR image. Compared with some traditional and classical speckle filtering methods, the invention can better smooth speckle noise and simultaneously keep the edge and texture details of the SAR image.

The invention relates to an airborne SAR radiation external calibration processing method based on weak arrangement of corner reflectors. The method comprises the following steps: obtaining original SAR image data of a calibration field; on the basis of a point target radar equation, reconstructing an radiation external calibration equation; performing stable estimation on calibrator image energy and geometric optical solution on a calibration RCS; carrying out fitting and correcting on a radar system transfer function to obtain preliminary radiation calibration SAR image data; carrying out the stable estimation on the calibrator image energy and the geometric optical solution on the calibration RCS; and estimating a system constant item so as to generate calibration data and obtain final radiation calibration SAR image data. According to the invention, on the basis of the point target radar equation, according to the characteristic of parameters of a radar system, the SAR radiation external calibration equation comprising a change system transfer function and a constant system constant item is reconstructed, the application process of radiation external calibration is simplified, and the problem is avoided that it is quite difficult for airborne SAR flight to obtain a large-scope homogeneous stable tropical rainforest area frequently used by similar spaceborne SAR radiation calibration.

A system for reception of electromagnetic waves in spectrum in which interference occurs comprising at least one transmitter; at least one receiver configured to receive the received signal; a first memory portion configured to store data relating to a point target response; a spectrum estimator configured to estimate the frequencies at which interfering signals occur; at least one processor configured to generate an estimation of the interfering signals at the frequencies estimated by the spectrum estimator; a second memory portion operatively connected to the at least one processor configured to store the estimation of the components of the interfering signals; the at least one processor configured to substantially reduce or eliminate radio frequency interfering signals from the received signal utilizing the point target response and the estimation of the interfering signals; and a method to substantially reduce or eliminate radio frequency interfering signals from for image data.

A territorial waters synthesis pore diameter radar image point target extraction method belongs to the technical field of image processing, which comprises steps below: Calculating point-wise Holder's index of an original image and enhancing two-valued obfuscation; inputting the processing result as an independent composition analysis method to obtain spatial expression of the image, viz. base image and independent composition; formulating separation basis to separate the space, obtain a noise space corresponding to noise signals and a non-noise space corresponding to non-noise signals; using a nonlinear filter operator to enhance the independent composition of the non-noise space and repeatedly restructure the independent composition and the acquired image to restore the original image; cutting two-valued extraction result of the territorial waters original image point target through simple threshold values. The present invention brings proper restriction upon strong ocean noise waves of the territorial waters synthesis pore diameter radar image.

The invention provides an FFBP SAR imaging-based autofocus method through which accurately focused SAR images can be obtained in eight steps. The method is based on an FFBP frame, phase gradient information of movement error is extracted by using phase difference information of adjacent sub-apertures of point targets, and movement error is estimated through an integration method and compensated to realize autofocus processing of high-accurate SAR images. Compared with conventional methods, the method is not affected by error order. Movement error of any orders can be estimated, and the robustness of autofocus algorithm is substantially improved. Error information is extracted by using phase difference of adjacent sub-apertures, which avoids repeated calculation of a nested overlapping sub-aperture method. Large-scale optimized searching is not required, computational burden is greatly reduced, and imaging time is shortened.

The invention discloses an improved Bayes non-local mean filter used in a synthetic aperture radar (SAR) image de-speckling method, which belongs to the technical field of image processing and mainly overcomes the problems of compressed brightness of strong reflection targets such as points, edges and the like and unsatisfied mean maintenance and the like in a de-speckling result of the original Bayes non-local mean filter. The method is implemented by the following steps: (1) performing mean pre-evaluation on an input SAR image v to obtain a pre-evaluated mean matrix u; (2) pre-selecting blocks in a search area at the xi position of a pixel point in the input SAR image, and marking the result as a block set delta 0; (3) pre-selecting points on elements in the block set delta 0, and marking the result as a point set delta; and (4) adopting the Bayes non-local mean filter on each pixel point in the input SAR image to obtain de-speckling image by using the mean matrix u and the point set delta. The method can realize mean and texture maintenance, better keep the brightness of strong reflection targets such as points, edges and the like and is favorable to point target and edge detection.

The invention discloses a sight tracking and aiming control system and a method. The system and the method can allow a user to control machinery equipment with eyes and rapidly aim, lock and track a fixed target. The sight tracking and aiming control system comprises sight tracking equipment, a sight tracking equipment and robot platform equipment relative position posture acquisition unit, and aiming control equipment, wherein the sight tracking equipment can track and compute a sight direction of the user and position coordinates of a fixation point; the relative position posture acquisition unit can measure and compute a relative position posture between a coordinate system of the sight tracking equipment and a coordinate system of the aiming control equipment; and the aiming control equipment can compute a direction and position coordinates of a fixation point target of the user in the coordinate system of the aiming control equipment according to the sight direction, the position coordinates of the fixation point, the relative position posture and the like, so that the control equipment aims, locks and tracks the fixation point target of the user. The system can also calibrate and correct the fixation point target of the user, so that the sight tracking, aiming and locking accuracy of the system is improved.

The invention discloses an SAR image de-noising algorithm based on Primal Sketch classification and SVD domain improvement MMSE estimation. The problem that in the prior art, details are fuzzy during SAR image de-noising is solved. The method mainly comprises the steps that firstly, in the Primal Sketch algorithm, an energy image is improved by the adoption of a dual-neighbourhood contrast enhancement method, then the Primal Sketch algorithm is adopted for dividing SAR images into a non-edge class and an edge class; NLSVD decomposition is carried out on the pixel points in the two classes, a singular value matrix is estimated by the minimum mean square error criterion containing constriction factors, and inverse transformation is carried out to obtain the estimation value of the edge class and the estimation value of the non-edge class; finally, edge coefficients are calculated, and the boundary of the edge class and the boundary of the non-edge class are fused through the Butterworth fusion method to obtain a de-noising result. According to the SAR image de-noising algorithm, speckle noise in the SAR image can be effectively removed, and the edge and point target information is well kept.

The invention discloses an airborne SAR (synthetic aperture radar) imaging method suitable for a large squint angle. The method comprises the following steps of: (1) establishing an echo signal model; (2) performing signal imaging by the steps of: (2-1) performing distance fast Fourier transform and azimuth fast Fourier transform on a point target signal; (2-2) performing distance inverse Fouriertransform and performing accurate treatment on the phase of the signal; (2-3) multiplying the result by a Chirpscaling factor; (2-4) performing distance Fourier transform; (2-5) multiplying the result by a distance compensation factor; (2-6) performing distance inverse Fourier transform; (2-7) multiplying the result by an azimuth compensation factor; and (2-8) performing azimuth inverse Fourier transform to obtain a compressed SAR image signal. In the method, by imaging the point target under a large squint angle, a good peak-sidelobe ratio and an integral-sidelobe ratio can be obtained; a relatively high spatial resolution can be obtained in the distance direction and azimuth direction by use of the SAR pulse compression technology and the synthetic aperture technology; and moreover, themethod performs distance relocation correction in a time domain, simplifies an echo signal distance model, reduces the two-dimensional coupling quantity, adopts accurate phase unwrapping, realizes accurate correction of the signal and has a relatively high processing speed.

The invention proposes a signal-level fusion networking radar anti-cheating interference method under object signal correlation, and the method can achieve the effective discrimination of false targets generated by different cheating interferences. The method comprises the steps: 1, enabling each junction radar to receive echo data and calculate a corresponding noise power; 2, building slow-time random complex envelope sequences of each point target at a plurality of junction radars; 3, estimating the mean power of each point target at each junction radar; 4, enabling the slow-time random complex envelope sequences of the same point target at the plurality of junction radars to be combined in a paired manner to form a plurality of envelope groups, and estimating a correlation tolerance; 5, calculating a detection threshold range; 6, searching an optimal detection threshold; 7, judging whether the correlation tolerance is greater than the optimal detection threshold or not: judging that the envelope groups pass through false target examination if the correlation tolerance is not greater than the optimal detection threshold, or else, marking two corresponding point targets as false targets; 8, eliminating the false targets.

A metrology system includes a laser, a position sensitive detector array, a first collimator, a second collimator, and a mirror. The position sensitive detector array and the first collimator are positioned at a reference point. The second collimator and the mirror are positioned at a point target at a distance from the reference point. A laser beam is alternately provided to the first collimator and the second collimator by optical fiber. The position sensitive detector array measures position data from a first laser crosshair generated by the first collimator and from a second laser crosshair generated by the second collimator. By alternating the activation of the first collimator and the second collimator it is possible to measure 5 degrees-of-freedom for the point target. A metrology system processing unit provides analog data processing. The metrology system that is suitable for, but not limited to, facilitating active compensation of large spacecraft structures.

The invention relates to a method for deciding an agile satellite earth observation task pretreatment scheme. A new target area decomposition and combination method is provided; a multi-attribute utility function is constructed according to a pretreatment method; task scheduling pretreatment schemes are sorted and selected according to the multi-attribute utility function method; a point target describing method based on 'moment-gesture' and a region target feature describing method based on time gesture vectors are provided; the describing method is utilized to provide a target decomposition and combination method in the pretreatment; for different parameter generating schemes, the optimal treatment scheme is selected through the multi-attribute utility function method.

The invention discloses a passive sensor networking detection multi-target method. A passive sensor networking system carries out intersection positioning by using a direction-finding intersection method according to angle information provided by a sensor; a ghost point is eliminated by using information redundancy static between multiple platforms; subsequently the ghost point is dynamically eliminated by using a virtual flight path tracking technique, so as to realize the accurate positioning and tracking on multiple targets. The method for eliminating the ghost point comprises the steps of: calculating each flight path tracking door; carrying out association processing on point targets (obtained from the intersection positioning) with each grade of flight path files in sequence in accordance with the flight path grades from high grade to low grade; and starting, combining, cutting, branching and deleting the flight path according to the association situation. The passive sensor networking detection multi-target method has the following advantages that target movement characteristics are sufficiently utilized, the ghost point is dynamically eliminated in the target tracking process, the engineering is strong in realizability, and the ghost point can be effectively eliminated under the condition that the targets are dense or measuring noise exists.

The invention discloses an SAR (Synthetic Aperture Radar) image de-noising method based on NSCT (Non-Subsampled Contourlet Transform) domain edge detection and a Bishrink model, mainly solving the problems of scratch effect and detail loss caused by carrying out the SAR image de-noising process by means of non-subsampled contourlet transform. The method comprises the following steps of: carrying out the non-subsampled contourlet transform on a selected SAR image and dividing the image into six layers of sub-band coefficients; keeping the first layer and the second layer of sub-band coefficients invariable and contracting the third to six layers of the sub-band coefficients by using the Bishrink model; reconstructing an image by means of non-subsampled contourlet inverse transform, and detecting an edge of the reconstructed image to carry out mean value filtering on the image subjected to the edge detection to obtain a filtered image; and carrying out non-linear anisotropism dispersion on a difference image obtained by subtracting the input image from the filtered image to obtain a de-noised image. The invention can excellently maintain edge information of the image and point target characteristic information, and can be used for interpretation analysis in the SAR image and pre-processing of image understand.

The invention discloses a moving platform adaptive expansion target tracking system and method based on a laser radar. The system comprises global positioning, local map generation, target detection and identification, motion target classification and adaptive tracking modules, wherein the global positioning module is used for acquiring the real-time position and the motion state information of amoving platform, the local map generation module is used for generating a local map corresponding to the present position according to laser radar data, the target detection and identification moduleis used for carrying out clustering and characteristic extraction processing of the local map at the present time and detecting and identifying a motion target, the motion target classification moduleis used for classifying targets into an expansion target and a point target, and the adaptive tracking module is used for realizing hybrid tracking of the expansion target and the point target at thesame time and realizing same target adaptive tracking model switching at different times. The system is advantaged in that extended target tracking is performed to enhance the target tracking effect,and mobile platform environment perceptual performance and adaptation capability are improved.