64 results about "Satellite orbit determination" patented technology

A transponder satellite communication navigation positioning system relates to the field of space technology. The system is equipped with a high-precision atomic clock at a ground communication navigation reference station, and the satellite orbit data is given by the satellite orbit determination system; the satellite integrity is given by the monitoring system The data forms the navigation message, and the ranging code composed of pseudo-random codes forms an integrated baseband signal, which is modulated by spread spectrum to form a navigation signal carrier, which is transmitted through the antenna and forwarded by 3 to 9 satellites in a certain geometric distribution in space The device converts the frequency and forwards the downlink, and broadcasts the signal to the coverage area; the ground user terminal receiving device receives the navigation signal carrier, and despreads and demodulates it to obtain the navigation data, thereby determining the position, speed and time of the user terminal receiving device. The invention has the advantages of low investment, guaranteed accuracy, convenient and flexible system maintenance and management, and dual functions of navigation and communication, so that the navigation and positioning accuracy can reach meter-level precision or be better than meter-level precision.

The invention discloses an autonomous synthetic aperture radar (SAR) satellite orbit determination method based on an extended kalman filter and belongs to the technical field of autonomous satellite orbit determination. Due to the adoption of a global positioning system (GPS) which adopts a half-autonomous orbit determination mode, the conventional autonomous satellite orbit determination technology has the problems of low autonomy and low instantaneity. By the orbit determination method, the problems can be solved. The method comprises the following steps of: 1, establishing a satellite motion equation based on orbit dynamics so as to obtain a state equation; 2, establishing an observation equation by taking a distance between an SAR and a ground identification point and a Doppler shiftfrom the SAR to the ground identification point as observation values; 3, establishing a recurrence equation of the extended kalman filter; and 4, thus obtaining state information of a satellite to obtain a position and a speed vector of the satellite. By the method, the orbit determination precision of the satellite is improved; the method has the characteristics of autonomy and instantaneity; and high-precision real-time autonomous orbit determination for low-orbit satellites can be realized.

The invention provides an autonomous orbit determination method based on a satellite borne processor. The method overcomes the difficulty of orbit determination precision divergency for navigation satellite orbit determination under the condition of breaking away from the support of a ground surface station by utilizing inter-satellite ranging, completes multiple steps of precise measurement data conversion among navigation satellites, reduction of different time measurement values, geometric orbit determination, dynamics orbit determination, autonomous ephemeris generation and the like, and achieves the navigation satellite autonomous orbit determination algorithm in breaking away from the support of top pouring of data of the ground surface station. The method not only has no measurement data of the ground surface station, but also has no top pouring data of the ground surface station under the condition of breaking away from the support of the ground surface station; navigation satellite only depends on the interstellar bidirectional measurement result and combines with the 60-day long-term forecast ephemeris prestored on the navigation satellite, and obtains the real-time orbit forecast result of the navigation satellite through the autonomous algorithm of the navigation satellite, and can generate broadcast ephemeris to send.

The invention discloses a GNSS (Global Navigation Satellite System) maneuvering satellite orbit determination method with additional clock error model constraint, comprising the steps of: acquiring observation data of an observation station; 2) eliminating observation data after maneuvering, and performing dynamic precision orbit determination calculation on arc sections before and during maneuvering; 3) extracting estimation values of a satellite clock error before maneuvering, an ambiguity, a receiver clock error during maneuvering, a ZTD (Zenith Tropospheric Delay) and an ISB (Inter-SystemBias) parameter; 4) establishing a clock error forecasting model based on the estimation value of the satellite clock error before maneuvering; 5) fixing the receiver clock error, the ambiguity without cycle slip, the ZTD and the ISB parameter, adding constraint of the clock error forecasting model, and performing orbit determination calculation on a satellite orbit during maneuvering by adoptinga reverse dynamic precision single-point positioning method; and 6) iteratively solving position parameters of the maneuvering satellite at the current epoch until the position parameters are converged, and performing solving at the next epoch. According to the GNSS maneuvering satellite orbit determination method of the invention, through introduction of the satellite clock error forecasting model constraint, the correlation between satellite orbit radial direction and the satellite clock error can be greatly weakened, and the orbit radial direction orbit determination precision of the maneuvering satellite is effectively improved.

The invention provides a Beidou PPP-RTK-based low earth orbit satellite space-time reference establishment method. According to the method, an observation equation is established by fully utilizing various error correction information broadcasted by Beidou PPP-RTK service, a navigation satellite precision orbit and a clock difference product; and a low earth orbit satellite space-time reference issolved by adopting a Kalman filtering parameter estimation strategy. Compared with an existing method, the method effectively avoids precision loss caused by resolving the space-time reference of a low earth orbit satellite by only adopting a navigation satellite orbit introduced by broadcast ephemeris and clock error precision difference, and also avoids precision loss caused by the fact that asatellite-borne receiver clock error absorbs various deviation items which are not accurately modeled; and the method has remarkable characteristics and advantages compared with a traditional low-orbit satellite orbit determination and time service method.

The invention discloses a low-orbit constellation system phase keeping method, system and equipment and a storage medium, wherein the method comprises the steps: determining the deviation between an actual semi-major axis and a reference semi-major axis of a satellite and the variation of the deviation along with time according to a reference flat phase angle and an actual flat phase angle of thesatellite; according to the deviation between the actual semi-major axis and the reference semi-major axis of the satellite and the variation of the deviation along with time, determining the orbit maneuvering time and the variation of the semi-major axis of the satellite; and adjusting the phase of the low-orbit constellation system in a satellite phase keeping task period by utilizing the satellite orbit maneuvering time and the semi-major axis variation. The technical scheme provided by the invention can be used for realizing high-precision phase retention of the low-orbit constellation system; under the conditions that the satellite position and speed determination precision is not high and the positioning data sampling rate is low, high-precision phase keeping (the precision requirement such as +/- 0.1 degree) can be achieved, and the requirements of high-precision phase keeping for satellite orbit determination precision and orbit determination data sampling storage are lowered.

The invention provides a technical scheme of simultaneously and precisely tracking a plurality of space objects only based on carrier observation data of ground monitoring equipment driven by an atomic frequency standard for fulfilling the purposes of high-precision orbit determination of regional navigation satellites and precise passive tracking of non-cooperative space objects. The invention designs a parameter evaluation estimation scheme of precise orbit determination only based on carrier phase data and provides a novel carrier phase cycle slip detection and repair method. The method makes full use of priori orbit and prior atomic clock speed information and is suitable for static users. The method is applied to orbit determination processing of an MEO (Medium Earth Orbit) satellite of a COMPASS system and is only based on carrier phase data of 6 regional ground stations, the mean residual of arc length orbit determination results of three days is 0.18m, and the mutual differences of one-day-arc overlap orbit are 0. 61m and 8. 09m in radial direction and three-dimensional position respectively; the mean residual of laser comparison is 0.28m; the mean residual of forecast for 24 hours and laser alignment is 1.34m. Compared with that of the prior art, the orbit determination precision is improved by 1 order.

The invention discloses an onboard GNSS-assisted Beidou navigation satellite orbit determination method, and relates to the technical field of earth observation and navigation. The method, by research of key technologies such as high-precision onboard GNSS tracking station epoch-by-epoch dynamic positioning, onboard GNSS Beidou satellite ambiguity determination, onboard GNSS-assisted Beidou satellite orbit determination, makes full use of the onboard (such as cargo ships and cruise ships in the oceans) GNSS data, optimizes tracking station configuration in BDS orbit determination, and assists precise Beidou navigation satellite orbit determination. The BDS precise orbit determination configuration is greatly enriched and BDS precision orbit system error is weakened because cargo ship onboard device air routes are everywhere in the oceans. Since there are many cruise ship routes, a dynamic location fills in the blank area of the tracking station, provides richer raw data for BDS precision orbit determination, improves the BDS precision orbit accuracy, and provides users with a more accurate track product.

The invention discloses a satellite orbit determination method for the eccentricity of a frozen orbit. The method comprises the following steps: setting an initial orbit parameter; converting the mean element of an orbit element to an instant element; calculating the orbit element within the service life under the assistance of STK (Satellite Tool Kit) software; performing extreme value processing to extract the eccentricity, and updating the frozen orbit. By adopting the method provided by the invention, the defects of complex calculation and long time during calculation by adopting a high-accuracy calculation method or simple calculation process and low accuracy in a low-accuracy calculation method during determination of the eccentricity of the original frozen orbit are overcome.

The invention discloses a method for predicting the orbit errors of a broadcast ephemeris by using an improved BP neural network, belonging to the technical field of satellite navigation data processing. The method for realizing the invention comprises the follow steps of: data required for predicting orbit error of broadcast ephemeris is collected by use of a BP neural network; the data needed byBP neural network is preprocessed; then the BP neural network model is constructed by using the preprocessed data; then the initial weights and thresholds of BP neural network model are optimized byPSO algorithm; the improved BP neural network model is trained again; finally, using the test data to evaluate the accuracy of the improved BP neural network model, the orbit error of broadcast ephemeris is predicted and compensated. The invention can reduce sensitivity to initial parameters, avoid falling into local minimum value, effectively improve satellite orbit determination accuracy and reduce system-level error of satellite navigation system.

The invention discloses a real-time precise point positioning method based on the satellite clock and R-orbit error mixed estimation. A real-time satellite clock error estimation terminal and a mobile station client terminal are adopted. The method includes that the real-time satellite clock error estimation terminal estimates the satellite clock errors in real time through broadcast Ephesus and regional CORS continuous observation data and transmits to a mobile station through a mobile network rapidly; the mobile station client terminal receives GNSS observation data and acquires and decodes satellite clock error data through the mobile network, and the precise point positioning is performed after data p reprocessing. By the aid of the method, the positioning precision and convergence time of precise point positioning are improved and increased significantly on the basis of the IGS real-time data flow method, the small-scale CORS application is supported, and the limitation that satellite orbit determination requires a large range of ground stations is overcome; a user of the mobile station only receives the real-time satellite clock error correcting data instead of precise orbit data, and the network communication load is reduced.

The invention discloses a satellite orbit determination system inserted in a mobile communication network. The satellite orbit determination system comprises a plurality of mobile communication base stations, a satellite data server and a plurality of mobile users. The satellite data server transmits calculated high-precision orbit parameters to the mobile users; the mobile communication base stations send collected original satellite data to the satellite data server; the satellite data server provides the calculated high-precision orbit parameters for a satellite ground control center; the satellite ground control center transmits satellite orbit correction to navigation geosynchronous satellites and inclined orbit geosynchronous satellites through satellite earth stations. Large-scale distributed mobile communication base stations are utilized to measure the original satellite data, and the satellite data server collects measurement data of the mobile communication base stations through networks, analyzes the measurement data, and calculates orbit parameters of the navigation geosynchronous satellites and the inclined orbit geosynchronous satellites to precisely determine satellite positions, so that the objective of improving accuracy of satellite navigation systems is achieved.

The invention provides a multiple parallel address receiver-based Beidou navigation satellite region orbit determination method. The method comprises the steps of aiming at tracking stations of a China regional network, selecting data of multiple receivers at each station, and generating a medium long reference line and an ultrashort reference line according to the principle of the maximal common view observed quantities; based on single difference data of the medium long reference line and the ultrashort reference line, generating dual difference data to perform primary satellite precise orbit determination, and obtaining an ambiguity floating point solution and an estimation parameter; tracking station coordinates, and adopting different methods to calculate carrier phase ambiguity for reference lines of different lengths; using the generated carrier phase ambiguity to re-perform parameter estimation to calculate a satellite orbit. The Beidou navigation satellite region orbit determination is carried out by using multiple receivers placed in a parallel-address mode, the calculation successful rate of the carrier phase ambiguity can be improved, the value of a carrier phase observation value in the Beidou navigation satellite region orbit determination is improved and the Beidou navigation satellite orbit determination precision is finally improved.

The invention aims at a problem of outer space noncooperative target precise orbit determination, and provides a space-based bearing-only measurement differential evolution one-time precise orbit determination method. In the method, based on thinking of least square batch processing orbit determination, a differential evolution algorithm is used to directly optimize an orbit determination objective function, thus, a situation of misconvergence or convergence errors, which may happen in a solving process of the direct least square batch processing method, can be avoided, moreover, a secondary orbit determination process required by general precise orbit determination is not needed, and an aim of one-time precise orbit determination can be realized. The method provided by the invention constructs a target orbit parameter vector based on an orbital kinetic equation description form, and under the situation of only using angle observation data, accurately solves an orbit spatial position and speed of the target at particular moment. A simulation experiment shows that an angle measurement sequence with precision of 5 seconds of arc is used, effective observation distance is in a range of 5000 kilometers, orbit determination precision of the method is as high as hundreds of meters order of magnitude, and the method can be used for a satellite orbit determination task.

The invention discloses a method and apparatus for satellite orbit determination. The method for satellite orbit determination comprises the steps of obtaining measurement data of a plurality of navigation systems; determining orbit determination data of the satellite orbit determination according to the measurement data of the plurality of navigation systems and weighting coefficients of the plurality of navigation systems; and performing satellite orbit determination according to the orbit determination data. Through the invention, combined orbit determination is conducted by introducing navigation star observation data of different navigation systems, the system completeness of a navigation receiver is improved, the number of available navigation satellites can be substantially increased, and the distribution geometry of the navigation satellites is improved.

The invention provides a navigation satellite multi-satellite orbit determination system and method based on satellite-ground bidirectional clock difference constraint, and the system comprises an error correction unit which is configured to carry out the error correction of the orbit determination pseudo-range observed quantity of different ground monitoring station receivers of a Beidou system according to the satellite clock difference, wherein the satellite clock difference comes from satellite-ground time synchronization based on a radio bidirectional method; and the system further comprises a multi-satellite orbit determination unit which is configured to perform multi-satellite precise orbit determination by using the orbit determination pseudo-range observed quantity corrected by the error correction unit.

The invention discloses an autonomous orbit determination method suitable for an initial launching stage of a low-orbit satellite. Earth magnetic field information measured by a satellite magnetometeris used as an observed quantity, a state equation and an observation equation are used, a recursion formula of state quantities which are a position, a speed and an attitude of a satellite is established under initial conditions, and orbit information is continuously corrected and output through iteration and filtering of multi-point information so that satellite full-magnetic autonomous navigation calculation is realized. The satellite can still calculate more accurate orbit parameters without depending on a GNSS system, and a ground system can ensure that a ground antenna continuously and stably tracks the satellite by using the orbit parameters downloaded by the satellite.

The invention provides a time frequency transmission receiver containing a GNSS common view comparison algorithm, belongs to the field of satellite navigation system receiver time comparison and research, and specifically relates to receiver hardware design. The time frequency transmission receiver containing a GNSS common view comparison algorithm includes a time frequency unit, a radio frequencyunit, a signal processing unit, a monitoring unit, satellite orbit determination, signal propagation delay correction and post processing of data, wherein the common view comparison algorithm includes the steps: establishing a pseudo range observation equation, performing troposphere time delay correction value and earth rotation effect correction value modeling, and performing filtering and postprocessing on the time comparison result in real-time. The time frequency transmission receiver containing a GNSS common view comparison algorithm has the advantages of 1) being easy to implement, carrying out the common view time comparison algorithm, and being able to realize time comparison only by letting the measured receiver to observing one satellite at the same time; and 2) being higher in the accuracy of the time comparison algorithm adding Kalman filtering and RTS post processing, compared with a pure common view time comparison algorithm.

The invention provides a satellite orbit determining method and device based on maximum model decomposition. The satellite orbit determining method comprises the steps that based on the KAM principle, a Fourier series expansion model of position coordinates of a satellite is established when the satellite operates on an orbit; according to the descending order of amplitudes, the Fourier series expansion model of the position coordinates is decomposed, and a decomposed similar series expansion model of the position coordinates is obtained; based on the actual observation values of the position coordinates of the satellite when the satellite operates on the orbit, the amplitudes and the corresponding frequencies in the similar series expansion model of the position coordinates are determined; through the similar series expansion model of the position coordinates, the position coordinates of the satellite on the orbit at any moment are predicated. The satellite orbit is determined more rapidly and conveniently by the adoption of the satellite orbit determining method and device based on maximum model decomposition, the satellite orbit determining method and device based on maximum model decomposition is practical, only the frequencies and the amplitudes of the satellite orbit need to be computed and stored in the predication process, storage resources are saved, and the processing efficiency is greatly improved.

The invention discloses a gravity gradient kinematic navigation method introducing pseudo measurement when considering deviations, and belongs to the field of autonomous navigation. The gravity gradient kinematic navigation method comprises the following steps that first, preparatory work is performed, specifically, a relevant calculation formula of the gravity gradient and representation of the gravity gradient in different coordinate systems are given; second, initial parameters of solution are set, data is prepared, and selection of an iterative initial value, a measurement variance and thelike is performed; third, an EGM2008 model is used for calculating a gravity gradient value and a partial derivative matrix of the gravity gradient to the position; fourth, the pseudo measurement isintroduced to construct a kinematic navigation observation model; and 5, a nonlinear least square method is used for iterative solution. Through the steps, the pseudo measurement is introduced, observation information is added, and then a gravity gradient sequential kinematic navigation observation equation considering the measurement deviations is constructed. The dependence on satellite dynamicconstraints in traditional satellite orbit determination application is eliminated, the application of gravity gradient navigation is extended to general objects, and thus greatly the application potential and value of gravity gradient positioning navigation are greatly improved.

The invention discloses a drift scanning camera synchronous satellite real-time orbit determination device. The device comprises a drift scanning CCD camera, wherein the drift scanning CCD camera is connected with a USB data acquisition card which is connected with FPGA programmable logic device, the FPGA programmable logic device is connected with a DSP image processing module which is respectively connected with a display driving module and a hard disc storage module which are used for displaying and storing the calculating result. According to the device, the DSP image processing module can be used for high speed arithmetic of big data, is programmable, and can be used for rapidly completing the large arithmetic amount in the synchronous satellite orbit determination to obtain the orbit determination result in real time, the real-time orbit determination of synchronous satellite is facilitated, furthermore, the structure is simple, the cost is low, and the reliability is high.

The invention relates to the technical field of satellite orbit calculation, in particular to a navigation satellite orbit determination tracking station optimization algorithm, which utilizes indexesto quantitatively analyze the distribution advantages and disadvantages of different tracking stations and the number saturation of orbit determination tracking stations, and provides technical support for selection of satellite orbit determination tracking stations of various navigation systems and site selection of a core reference station. According to the algorithm, the positions and the number of the navigation satellite orbit determination ground tracking stations can be optimized on the premise that no ground tracking station observation data exists, compared with an existing trackingstation distribution optimization algorithm, the calculation efficiency is improved, an optimization algorithm of the number of the tracking stations is added, and meanwhile fusion analysis of multiple types of observation values can be compatible; moreover, the optimization algorithm designed by the invention is universally suitable for different navigation systems, and is also suitable for optimization of the orbit determination tracking station during fusion processing of multiple types of observation values.