26 results about "Double star" patented technology

The invention discloses a method for carrying out correlation and orbit determination on a space target based on a double-star optical observation result, and the method comprises the steps: obtaining the observation vectors of two observation stars for a certain space target in the respective visual fields, calculating the shortest distance between the observation vectors, and if the distance is always smaller than a threshold value in a time sequence, determining that the space target does not exist. And if not, determining that the two observation stars observe the same space target, calculating a midpoint of two observation vector common vertical lines of the same space target by the two observation stars as an orbit determination point, and performing orbit determination on the space target based on an orbit determination point sequence. According to the method, a low-cost space-based optical orbit determination mode is adopted, space target association is completed through an algorithm with low calculation cost, target consistency is judged based on observation vector distance constraints, a complex model or a large amount of calculation power is not needed, efficient processing can still be performed when the number of targets is large and the data size is large, and the cost and efficiency advantages are remarkable.

The application discloses a kind of optimal matching double star SAR fusion imaging methods based on CRLB.Global navigation satellite system (GNSS) has the advantages such as all-weather operation and extensive spatial coverage, although the GNSS-R SAR technology for ground synthetic aperture radar (SAR) imaging using reflected signal of GNSS is low in cost and widely used, but because the bandwidth of GNSS signal is limited, its resolution is poor.The application establishes the SAR fusion imaging system model by multiple satellites and a single ground fixed GNSS receiver, explores the interrelation between the ambiguity function of GNSS signal and Fisher information, and deduces the system Cramer-Rao lower bound (CRLB) affected by the geometry configuration of bistatic setting.On this basis, the satellite in the optimal resolution direction for ground target is identified by using CRLB expression, and the imaging results of selected satellite are incoherently fused according to the principle that the included angle between optimal resolution directions is as close to 90 degrees as possible.Through this method, unnecessary redundant imaging processing is avoided, and imaging resources are most reasonably used.The resolution performance of the system is improved in a more efficient way.

An inter-satellite pointing target attitude high-precision real-time online prediction method, first, the ground uses the orbit determination program corrected by on-orbit data observation to generate a double-satellite orbit position and velocity value sequence in a predetermined time period, and samples according to the control period, then for each sampling time, the double-satellite orbit position and velocity is used to establish the local orbit coordinate system, and the component of the target star position vector in the local orbit coordinate system is calculated, the pitch and yaw target attitude angle values are calculated according to the target attitude angle definition, the pitch target angle sequence is linearly averaged and estimated, the average orbit period value and the long-term change rate parameter are calculated, and the modified sequence after deducting the long-term change rate is given, for the pitch target angle correction sequence and the yaw target angle sequence, data of a specified average orbit period number is taken from a specified initial time, the fitting coefficient is calculated, finally the generated fitting coefficient is uploaded to the satellite, and the satellite uses the high-precision fitting determination formula to calculate the inter-satellite pointing target attitude angle online every control period.

The invention discloses a navigation mode transition method, an electronic device and a medium, in a working process of a first navigation mode, geometric angles among a mother satellite, a service spacecraft and space debris are monitored, and when the geometric angles meet a mode switching requirement, the position of a target orbit under a J2000 coordinate system is obtained through double-satellite geometric estimation; and taking the position as an initial position calculated in the second navigation mode, and switching to the second navigation mode. Before the navigation mode is switched, the target orbit position is determined through double-satellite geometric estimation, the single-satellite navigation positioning precision can be rapidly improved, a good initial value is provided for double-satellite angle measurement filtering, and the convergence process is accelerated.

The invention discloses an astronomical experimental device for simulating the photometric change of double food stars, and the device comprises a fixing unit which comprises a supporting part located at the lower part, an angle display part disposed at the top end of the supporting part, and a length display part transversely disposed on the angle display part. The limiting component is arranged on the angle display component, and the angle display component and the length display component are connected in series through the limiting component; the limiting unit comprises a fixing part located on the length display part and an adjusting part arranged below the fixing part. The invention provides a device capable of meeting more use requirements, improving the use efficiency of the device, facilitating the smooth proceeding of experimental work, and providing a device capable of recording the luminosity change and simulating the luminosity change conditions of different stages of a food double-star experiment by controlling the movement and the shielding degree of a star, so that the experimental efficiency of the food double-star experiment is improved. And thus, a scientific research scheme in the aspect of eating double stars in astronomy can be better assisted for working personnel.

This invention discloses a near-space target localization method based on dual-satellite imaging, comprising: simultaneously acquiring original observation images of the same target using two low-Earth orbit (LEO) satellites; acquiring the centroid coordinates of the target region in the two original observation images respectively, and performing coarse localization based on the centroid coordinates to obtain the coarse localization point coordinates of the near-space target; performing forward path correction to generate a simulated image of the target observed by the two LEO satellites under the current localization; performing residual correction on the estimated spatial position of the target to obtain the residual-corrected spatial position of the target; and repeating the above steps based on the residual-corrected spatial position in the current iteration until the iteration conditions are met to obtain the precise localization of the target. By constructing a closed-loop technical scheme of "dual-satellite synchronous imaging - coarse localization - non-uniform atmospheric and imaging system effect coupling correction - image centroid comparison - iterative optimization", the accurate inversion of the three-dimensional position of near-space targets can be achieved.

The application provides a method and device for optimal resource allocation decision of star group cooperative observation of space targets. The method comprises: obtaining input parameters, state parameters, constraint parameters and optimization variable parameters; based on the input parameters, the state parameters and the constraint parameters, calculating a benefit coefficient of observation of each target by each satellite, and updating each benefit coefficient based on the optimization variable parameters; calculating a cost coefficient matrix of double-star cooperative observation of targets according to the updated benefit coefficients, and constructing an optimal resource allocation decision model based on the cost coefficient matrix, so as to allocate satellite resources by using the optimal resource allocation decision model. According to the scheme, real-time and rapid optimal solving on the star can be facilitated, so that optimal resource allocation is realized.

This invention relates to a clustering method for observation targets based on continuous observation constraints of two satellites, comprising the following steps: at each moment, determining whether the observation target is physically potentially visible relative to the satellite using off-axis angle constraints and detection distance constraints; when the observation target is physically potentially visible relative to the satellite, using direction vector similarity analysis to extract the spatial nearest neighbor targets of the observation target, constructing a set of satellite line-of-sight candidate directions pointing towards the geometric center of the observation target group; selecting the optimal satellite line-of-sight candidate direction that covers the most observation targets from the set of satellite line-of-sight candidate directions; and setting the sliding window length to seconds, selecting the optimal set of observation targets at each moment within the sliding window, and taking the intersection of all optimal sets of observation targets to select the intersection target group that is always located in the optimal field of view corresponding to the optimal satellite line-of-sight candidate direction within the sliding window as the continuous observation target set.

The application discloses a kind of double-star formation SAR high-keeping imaging method and device, first to the main star raw echo and auxiliary star raw echo of double-star formation SAR system is carried out spectrum pre-filtering processing, filter out the phase error between main and auxiliary images caused by non-overlapping range beam spectrum and azimuth beam spectrum;Establish the relationship equation set of Doppler characteristics and transmission slant range, solve the accurate value of target point and transmission slant range component, calculate main and auxiliary star imaging parameters;Using hyperbolic equivalent method and ECS imaging algorithm, main and auxiliary stars are simultaneously imaged, and high-keeping main and auxiliary star SAR images are obtained simultaneously, to realize double-star integrated SAR imaging.The above-mentioned method and device can realize high-keeping imaging to double-star formation SAR raw echo, reduce development cost and can realize good focusing effect, ensure timeliness, suitable for engineering application double-star SAR data fast imaging processing.

The application discloses a space-based space target trajectory segmentation fitting method based on infrared radiation characteristics, and comprises the following steps: (1) acquiring initial positioning information of a space target in a ground-fixed coordinate system through double-star joint observation; (2) monitoring the infrared radiation intensity of the space target in real time through an infrared sensor, identifying the classification points of the space target in different flight stages according to the infrared radiation intensity and signal-to-noise ratio change, and completing target trajectory segmentation; (3) for different flight stages, the least square method is introduced through an adaptive factor, the trajectory optimization fitting of the space target in the space-based scene is completed, high-precision positioning and tracking are realized, and the motion characteristics of the target are acquired. By using the application, the overfitting or underfitting problems in the traditional method can be reduced, so that the precision and reliability of space-based space target detection and tracking are improved, and the application is suitable for a complex space target observation environment.

The invention provides a satellite-borne monostatic / bistatic synthetic aperture radar (SAR) bunching imaging combined time sequence construction method and system. The method comprises the following steps: acquiring main and auxiliary satellite parameters; constructing the pulse repetition frequency of the monostatic / bistatic SAR system based on double-star observation geometry; constructing a bunching imaging primary satellite single-base transmitting / receiving time sequence; constructing a beaming imaging mode cosatellite bistatic receiving time sequence; and outputting main and auxiliary satellite transmitting and receiving time sequences. According to the method, a unistatic / bistatic SAR combined time sequence construction method is effectively broken through, multi-constraint PRF combined optimization, bistatic time sequence cooperative fault tolerance and space-variant characteristic source inhibition measures are provided, and the problems of bistatic transceiving separation, time-frequency synchronization, space-variant compensation and the like which cannot be dealt with by a traditional unistatic SAR time sequence construction method are solved; and a set of complete bistatic time sequence construction system is formed, and the engineering practical value is higher.

The application discloses a kind of space laser communication transceiving systems and methods with multi-wavelength self-loop test function, solve the problem that after laser communication load is launched into orbit, existing technology cannot carry out fast on-orbit self-checking to optical communication transceiving subsystem device, module, circuit etc..The application forms self-test loop light path to the transmitted multi-waveband high-speed laser signal by switching the polarization state of high-speed laser signal, using the principle that polarization beamsplitter group reflects S light and transmits P light, before implementing double-star chain building, self-checking test of the star can be realized, and the transmitting light path is not affected, only need to switch laser polarization state, through single byte telemetry data, the on-orbit state of optical communication transceiving subsystem can be judged, under the urgent condition that satellite transit time is short and test steps are many, on-orbit self-checking test can be quickly and effectively completed.

The application discloses a kind of navigation star library construction methods of approximate uniform distribution under small field of view condition, comprising: (1) using VMT algorithm, set threshold to SAO star table is segmented, only keep following navigation star, store in star library StarLib;(2) in star library StarLib, eliminate the navigation star of brightness and position not fixed, star distance value is too small, that is, eliminate variable star and binary star, obtain basic star library (StarLib1);(3) using approximate uniform distribution of spherical spiral reference point, according to the angle distance between reference point and star, star, the combination characteristics of three star density to rough navigation star, obtain preliminary navigation star library (StarLib2) and alternative star library (StarLib3);(4) on the basis of StarLib2, using KernelSVM-SMO from nonlinear distribution StarLib3 star library, select navigation star, calculate the average value of angle distance between selected star and existing navigation star in current field of view, judge whether less than set threshold, to effectively avoid redundant star, obtain final navigation star library (StarLib4).

A kind of double star formation satellite lightweight autonomous task planning and scheduling method based on multi-objective optimization, the method based on on-board constraint, realize the comprehensive performance optimal double star formation satellite autonomous task planning and scheduling, ensure the high-precision inter-satellite pointing and inter-satellite distance keeping during long-term operation of double star.This application takes the distance between double stars and the execution ability of satellite thruster as constraints, establishes a mathematical model of task planning, generates formation reference star scheduling and orbit / attitude control strategy based on multi-optimization objectives, realizes the full autonomy, lightweight, comprehensive performance optimal rapid autonomous task scheduling on board.

The application discloses a double-star fly-around orbit design method and system and electronic equipment. The core algorithm of the method is a new double-star global coverage algorithm improved from a grid point method and a Monte Carlo algorithm, a related coefficient k value range in initial orbit parameters of micro-nano satellites is determined according to micro-nano satellite parameters, double-star global observation fly-around coverage is calculated according to the initial orbit parameters meeting the related coefficient k value range, space station coverage is determined, double-star fly-around configuration coverage characteristics of the whole surface of the space station are analyzed, and the double-star fly-around orbit facing the whole surface observation of the space station is obtained. The application can effectively provide a model, a method and a basic design idea for global patrol monitoring of the surface of the space station.

The invention discloses a satellite-borne laser terminal rotary table pointing zero offset calibration method using double star sensors. Relates to the technical field of spacecraft attitude measurement and pointing control crossing, in particular to a satellite-borne laser terminal rotary table pointing zero offset calibration method using double star sensors. According to the method, a complete attitude transfer chain model is established, inertial attitude data output by a platform star sensor and inertial attitude data output by a terminal star sensor are fused, so that the measurement relative attitude of the terminal star sensor relative to a satellite platform is constructed, and the measurement attitude and a pre-established theoretical attitude chain model are subjected to high-precision alignment; a nonlinear estimation model about the azimuth coding angle zero offset and the pitching coding angle zero offset of the rotary table is constructed, the azimuth and pitching zero offset values of the rotary table can be autonomously estimated in an on-orbit mode with high precision by solving the problem, and finally on-orbit autonomous calibration of the pointing zero offset of the rotary table is achieved. The whole process does not need ground intervention, and the autonomy and long-term stability of satellite pointing control are effectively improved.

The invention provides a design method and device for a double-satellite-following low-ambiguity mixed polarized SAR system, and belongs to the technical field of radars, and the method comprises the steps: transmitting orthogonal circularly polarized waves through two SAR satellites, carrying out the collaborative observation of the same scene, obtaining the polarization information of a static target, and forming a double-satellite-following distributed mixed polarized SAR system; carrying out registration and phase synchronization on a double-star image in the distributed hybrid polarimetric SAR system followed by double satellites to obtain hybrid polarimetric SAR data; and reconstructing a low-ambiguity complete polarization scattering matrix based on the mixed polarization SAR data. According to the invention, the application potential of the polarimetric SAR system is improved, and the defects of low observation breadth, low resolution and low observation range of a complete polarization mode are overcome.

The application provides a method and device for double-star fault identification, electronic equipment and a storage medium, applied to the technical field of satellite navigation, and singular value space vectors and singular value space matrices are obtained by singular value decomposition of an observation coefficient matrix in pseudorange observation. Then, a singular value fault plane is constructed by using the singular value space matrix under double-star fault. Considering the influence of observation noise, whether there is double-star fault can be determined by the angle between the singular value space vector and the singular value fault plane. Through this geometric determination algorithm, the problem of being affected by the identification threshold in double-star fault identification is effectively solved, thereby avoiding the occurrence of missed detection and false alarm.

The invention relates to the technical field of spacecraft attitude determination, and particularly provides a double-star sensor attitude determination method and an attitude determination precision verification method and system.The method comprises the steps that absolute time and trigger time are generated based on a time synchronization signal; acquiring current output data of the two star sensors; comparing the timestamps with the triggering moments, and processing quaternions corresponding to the triggering moments according to different comparison results to obtain time-synchronized target quaternions; calibrating through a theodolite to obtain a first mounting matrix and a second mounting matrix of the first star sensor and the second star sensor to the same reference; and fusing the time-synchronized target quaternion based on the first installation matrix and the second installation matrix to obtain the attitude quaternion after fusion of the double star sensors. According to the double-star-sensor attitude determination method and the attitude determination precision verification method and system, time alignment of cross-equipment data is realized, and independent, repeatable and high-confidence evaluation of measurement precision of the star sensors and fusion algorithms thereof is realized at the same time.

1. The name of the design product: firework base (double star). 2. The use of the design product: for firework base. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view 1.

An inter-satellite pointing target attitude high-precision real-time online prediction method comprises the steps that firstly, an orbit determination program obtained after on-orbit data observation and correction is used on the ground to generate a double-satellite orbit position and speed value sequence in a preset time period, sampling is carried out according to a control period, then a satellite orbit coordinate system is established through the double-satellite orbit position and speed at each sampling moment, and the orbit position and speed value sequence is obtained; calculating a component of a target satellite position vector in an orbital coordinate system of the satellite, calculating a pitching and yawing target attitude angle value according to a target attitude angle definition, performing linear average estimation on a pitching target angle sequence, calculating an average orbital period value and a long-term change rate parameter, and giving a correction sequence after deducting a long-term change rate; and for the pitching target angle correction sequence and the yaw target angle sequence, data of a specified average orbital period number is taken from a specified initial moment, a fitting coefficient is calculated, finally, the generated fitting coefficient is uploaded to a satellite, and a high-precision fitting determination formula is used for calculating the inter-satellite pointing target attitude angle on line in each control period of the satellite.

The invention discloses a double-star positioning and error analysis inhibition method for a small-view-field star sensor, which comprises the following steps of: firstly, reading measurement data of the small-view-field star sensor, selecting two navigation stars, calculating star vectors of the navigation stars, aligning data of the two navigation stars at different moments to the same moment, resolving a double-star positioning result, converting the double-star positioning result into spherical coordinates, and carrying out error analysis on the spherical coordinates. The unique position of the carrier is determined according to data at the previous moment, and finally effective positioning results are screened through criteria. According to the method, aiming at the characteristics of the small-view-field star sensor, the invalid positioning result caused by error amplification is removed by processing observation navigation star data and fully considering an error amplification mechanism of double-star positioning, so that the confidence coefficient of the double-star positioning result of the small-view-field star sensor is improved.

The application discloses a kind of double star cooperative observation air movement target real-time positioning method, steps are as follows: 1, using target detection and tracking algorithm, respectively from the air movement target sequence image that two optical remote sensing satellites current time simultaneously shoots in detection target's particle coordinates;2, according to optical remote sensing satellite imaging mechanism and air target movement characteristics, constructs air movement target movement track fusion model;3, using movement track sliding solution method: using the particle coordinates of air movement target on two satellite sequence images, constructs standard error equation and iteratively solves air target movement track parameters;4, according to movement track parameters, solves the spatial position and speed of air movement target at current time.The application can eliminate the influence of double star time synchronization error on air movement target positioning accuracy from model itself, realizes the high-precision real-time positioning of double star cooperative observation air movement target.

The application relates to a kind of double-star electromagnetic formation dynamics modeling and control method of port Hamilton system, comprising: defining two slave spacecraft center-of-mass position coordinates in ECI coordinate system and LVLH coordinate system;According to the center-of-mass position coordinates of slave spacecraft, the kinetic energy and potential energy of slave spacecraft in ECI coordinate system are obtained;According to the center-of-mass position coordinates of slave spacecraft and the coordinate transformation matrix, the Lagrangian function L in LVLH coordinate system is obtained;The Euler-Lagrange equation is established, according to Legendre transformation, the generalized momentum coordinates p j are selected, the Hamilton function H is obtained, and the port Hamilton dynamics model is established;An electromagnetic formation controller is designed according to the trajectory tracking passive control method based on interconnection-damping distribution;The electromagnetic satellite formation trajectory tracking magnetic dipole strength control law is obtained according to the electromagnetic formation controller.The application retains the nonlinear term of the system, embodies the inherent dissipation characteristics of the system, can avoid the problem of reducing the accuracy of the system caused by linearization, and ensures the passivity of the system.

The invention discloses a method and a system for identifying cyanobacterial bloom risk based on double-satellite cooperation. The method comprises the following steps: S1, constructing an A-satellite lightweight chromaticity boundary triggering model and a B-satellite refined spectrum risk classification model based on historical data; s2, preprocessing and identifying a target water body area by using an A satellite receiving image, and converting the multispectral reflectivity value of each water body pixel into a CIE chromaticity space to obtain a chromaticity coordinate; judging whether the chromaticity coordinates exceed a preset boundary or not, and if the chromaticity coordinates meet a triggering condition, scheduling a satellite B through an inter-satellite communication link; s3, the satellite B responds to the scheduling instruction, analyzes a task triggering report, obtains an image extraction pixel multi-dimensional feature system, calculates risk scores by using a spectrum risk classification model, grades the risk scores, and outputs an identification result; according to the method, the A star uses the chromaticity boundary triggering model to screen and dispatch the B star, and the B star uses the spectrum risk classification model to perform refined evaluation, so that double-star cooperative identification of the cyanobacterial bloom risk is realized.

The application discloses a kind of on-orbit calibration methods of follow sight measurement error based on GNSS, relative position relationship between two stars is calculated by using double star GNSS differential data, and this is used as the reference value of follow sight measurement calibration, the measurement error of spaceborne follow sight radar is obtained by calculation, and the corresponding relationship between the measurement error of spaceborne follow sight radar and the position of the sun is obtained by further fitting, for ground number correction compensation.The application reduces the influence of follow sight radar measurement system error, improves the precision of follow sight radar on-orbit measurement, and can meet the high-precision relative measurement requirements of close-range double-star companion flying task.