505 results about "Ephemeris" patented technology

The invention relates to a space-ground integrated Beidou high-precision positioning method applied to urban canyons, and belongs to the technical field of navigation positioning. The method comprises the following steps: deploying a pseudo satellite base station, calibrating coordinates of the base station through carrier phase difference, and monitoring the number of Beidou visible satellites; a master pseudo-satellite is determined, timestamps and ephemeris data are broadcasted to slave pseudo-satellites through Beidou short messages, and the slave pseudo-satellites are combined with bidirectional ranging data to correct a local clock to realize high-precision synchronization; receiving Beidou and pseudo-satellite signals by a user terminal, screening effective observation values through a shielding judgment mechanism, substituting the effective observation values into a non-difference observation equation in combination with pseudo-satellite reference difference data, and resolving a fusion result through an elastic coupling mode; and finally, multi-path interference is identified by using pseudo-satellite double antennas, and historical data is called to construct an error model to correct a fusion result. The space-ground integrated positioning of Beidou and pseudo satellites in an urban canyon scene is realized, the centimeter-level positioning precision is stably output, and the high-precision positioning requirements of urban traffic, surveying and mapping and the like are met.

A Beidou / GNSS-based real-time high-precision sea surface measurement method and a buoy, wherein by using free-to-use broadcast ephemeris freely broadcast by GNSS satellites, precise point positioning of China's Beidou satellites, and other high-precision service space signals, real-time centimeter-level element information comprising time, longitude, latitude, water level, wave height, wave period, wave direction, sea surface current velocity and direction, atmospheric water vapor content, and the like can be directly obtained. The information can be stored locally in a buoy or transmitted back by communication, and is suitable for real-time high-precision sea surface measurements in offshore and far-sea scenarios.

The invention provides a regional interference signal detection method and device based on a Beidou router, and the method comprises the steps: obtaining reference broadcast ephemeris data of a network platform and local ephemeris data received by the Beidou router, carrying out the data integrity calculation, and judging whether the local ephemeris data are missing or not; performing same-epoch data comparison on the reference broadcast ephemeris data and the local ephemeris data, and judging whether the local ephemeris data has deception signals or not; calculating a visible satellite integrity rate in a fixed time window based on the observation data of the Beidou router, and judging whether interference signals exist in the observation data or not; analyzing by utilizing the cycle slip ratio and the carrier-to-noise ratio of the observation data, and judging whether interference signals exist in the observation data or not; under the condition that local ephemeris data do not have missing and deception signals and the observation data do not have interference, whether the observation data have the deception signals or not is judged based on pseudo-range single-point positioning and inter-epoch carrier phase difference velocity measurement, and the method can improve the reliability of Beidou signal interference detection.

The invention relates to the technical field of communication networks, in particular to a resource allocation system and method in a satellite-ground fusion network, and the system comprises a satellite-ground topology and channel evolution predictor which is used for obtaining satellite ephemeris, user GNSS positioning and moving vectors, ground base station topology and a real-time CQI / RSRP measurement report; generating future link state information; the business QoE impact and switching cost modeling device is used for calculating transient interruption time of a switching action; generating switching cost information; the continuity risk quantification engine is used for generating continuity risk information containing the link maintaining risk probability, the instantaneous impact collapse probability and the link switching risk probability; the risk evasion type resource decision-making device is used for calculating maintenance link comprehensive cost and switching link comprehensive cost; calculating a dynamic switching damping threshold value; generating risk avoidance decision information; according to the invention, the high-frequency ping-pong switching near the edge state point is effectively inhibited, and the signaling overhead caused by invalid switching is reduced.

The invention provides a GNSS data quality prediction method and device based on a fisheye camera, and a medium, and belongs to the technical field of data processing, and the method comprises the steps: determining the satellite orbit information of a future time period with a to-be-evaluated observation station as a reference point based on ephemeris prediction; according to the fisheye sky image shot at the to-be-evaluated observation station and the satellite orbit information, determining satellite feature data of a future time period and the occlusion porosity of the future time period; respectively inputting the occlusion porosity of the future time period and at least part of satellite feature data of the future time period into a general prediction model and an observation station prediction model corresponding to the observation station to be evaluated for data quality evaluation, and obtaining a first data quality evaluation index and a second data quality evaluation index; and determining a data quality prediction result based on the first data quality evaluation index and the second data quality evaluation index. A general prediction model and an observation station exclusive prediction model are introduced to carry out double-model evaluation, and accurate prediction of GNSS observation data quality is realized.

The invention relates to the technical field of spacecraft orbit control and space safety, and discloses a space debris orbit prediction and avoidance method, which comprises the following steps that: a ground computing center screens candidate targets and generates enhanced data packets for uploading; the spaceborne computer combines real-time navigation data to carry out geometric feature screening, and an instant high-risk target list is generated; controlling the star sensor to execute optical observation, and resolving an optical measurement relative orbit state by utilizing displacement superposition and Kalman filtering; selecting a high confidence coefficient or a conservative probability threshold according to the optical measurement state acquisition condition, and generating an avoidance instruction when the collision probability exceeds the limit; and the propulsion system responds to the instruction to execute avoidance, verifies the effect by confirming the semi-major axis variation and executes track recovery by selecting an aircraft. According to the method, the ground-air collaborative screening and shift superposition enhancement technology is adopted, the problems that the low-precision ephemeris false alarm rate is high and the detection capability of a satellite-borne sensor on a dark and weak target is insufficient are solved, and the accuracy of evasion decision making and the execution reliability are improved.

The embodiment of the invention provides a downlink signal sending method and a downlink signal processing method, which are characterized in that a downlink signal is obtained on the satellite side based on a supplementary synchronization sequence, and then time-frequency synchronization is carried out on the terminal equipment side by using the downlink signal from the satellite. In the application, the terminal device can realize time-frequency offset tracking compensation without acquiring satellite ephemeris information and using GNSS (Global Navigation Satellite System) equipment, so that the influence of ephemeris errors and GNSS errors on time-frequency synchronization performance after the terminal device is shut down for a long time is eliminated, and the problem that the time-frequency synchronization performance of the terminal device is influenced in the related technology is solved. The problem of low precision of time-frequency offset tracking compensation in the satellite-ground communication process is solved, and the time-frequency synchronization success rate of satellite-ground communication under the conditions of inaccurate ephemeris and high speed is improved.

The invention discloses a satellite navigation positioning method and device based on scene recognition, electronic equipment and a storage medium, and belongs to the technical field of satellite navigation positioning, and the method comprises the steps: determining the geometric space characteristics of each satellite according to the observation time, the satellite number of each satellite and preset satellite ephemeris information; according to the observation time, the satellite pseudo-range of each satellite and the satellite distance change rate of each satellite, determining the signal quality characteristics of each satellite; determining a satellite observation feature set based on the geometric space features of the satellites and the signal quality features of the satellites; inputting the satellite observation feature set and the satellite signal-to-noise ratio of each satellite into a preset scene recognition model to generate a scene category; and determining the positioning coordinate of the satellite navigation receiver according to the scene category in combination with the satellite signal-to-noise ratio of each satellite and the satellite pseudo-range of each satellite. According to the invention, the problem that satellite navigation positioning is not accurate enough in the prior art can be solved.

The invention discloses a radiation correction method and system for an airborne hyperspectral imager. The radiation correction method and system are used for improving the radiation correction precision in complex weather. The method comprises the following steps: calculating a theoretical sun position based on unmanned aerial vehicle initial coordinates, ephemeris data and atmospheric parameters; performing course and differential compensation on a solar azimuth angle by combining IMU course and wind speed and direction data, performing refraction correction on an elevation angle, and outputting a high-precision sun position parameter; hyperspectral images and irradiance data are synchronously acquired, quaternion interpolation is combined with IMU data to realize space-time alignment, and attitude disturbance is eliminated; a hemispherical space irradiance model is constructed based on alignment data, cloud layer modes (clear sky, thin cloud and thick cloud) are divided according to atmospheric optical thickness variance, and Lambert body proportion correction, a discrete longitudinal standard method or a deep convolutional spectral network are respectively adopted for radiation correction. The method remarkably improves the correction precision and generalization ability, supports large-area image splicing, and is suitable for quantitative application of geological exploration, environment monitoring and the like.

The invention discloses a multi-satellite service converged communication management control optimization method, which belongs to the technical field of satellite communication networks, and comprises the following steps: acquiring a service priority index and satellite ephemeris data, calculating the relative position between a satellite and a terminal at a future moment, and generating a satellite motion trail prediction result and an interference risk prediction result; and obtaining a load state of the satellite, dynamically calculating a resource allocation weight matrix to switch a satellite link in combination with a service priority index, a satellite motion track prediction result and an interference risk prediction result, and generating a resource allocation instruction and a switching command. According to the method, the resource allocation weight matrix is dynamically calculated by adopting the fusion service priority index, the satellite motion and interference prediction and the satellite load state, and link switching and resource allocation are performed according to the resource allocation weight matrix, so that prospective optimization management and intelligent control of multi-satellite communication resources can be realized, and the continuity and reliability of service fusion communication are improved.

The invention provides a two-line element generation method and orbit prediction method adaptive to an analytic propagation model, and the method comprises the steps: obtaining the historical osculating orbit elements at each epoch moment, and carrying out the orbit element optimization step of a plurality of iteration rounds on each historical osculating orbit element through employing the analytic propagation model, obtaining a target osculating orbital element number at each epoch moment, enabling the historical osculating orbital element number to be the same as the target osculating orbital element number, and performing inversion to obtain an average orbital element number; and extracting each average semi-major axis of each average orbital element, fitting each average semi-major axis by adopting a least square method to obtain a semi-major axis attenuation rate, inverting the semi-major axis attenuation rate to obtain an atmospheric resistance parameter, and equivalently converting the atmospheric resistance parameter into a standard resistance term in two rows of elements to obtain the two rows of elements. According to the method, the problems of inconsistent models, insensitive residual errors, unable physical explanation of parameters and the like in the two-line element generation process can be solved, and the ephemeris extrapolation orbit prediction precision is improved.

The invention discloses a rainstorm ground waterlogging prediction method, device, equipment and product, and relates to the technical field of urban waterlogging prediction.The rainstorm ground waterlogging prediction method comprises the steps that ephemeris and ground observation station data are obtained, the atmospheric moisture delay amount and the high-altitude water vapor conversion factor are calculated respectively, the historical water vapor content is calculated, and the future atmospheric precipitable water amount is predicted; rainfall time distribution data are obtained through rainstorm intensity decomposition; calculating the rainwater overflow amount of the catchment area in combination with the water discharge amount time distribution data of the urban drainage pipe network; and iterative calculation is carried out by using a digital elevation model grid to obtain the waterlogging depth, and waterlogging early warning information is sent out. By constraining the total rainfall amount, the rainfall amount can be effectively constrained by predicting the precipitable water amount based on the satellite ephemeris; the underground pipe network drainage is restrained, and a water flow condition in a pipe channel is simulated by adopting an SWMM model; and finally, the waterlogging accumulated water volume is calculated, constraint verification is carried out on each link of urban waterlogging, and relatively high precision and relatively long timeliness are ensured.

The invention discloses a low-orbit satellite communication terminal power consumption optimization method, and relates to the technical field of satellite mobile communication and wireless communication terminal power consumption management. A candidate set is generated based on satellite ephemeris and shielding information, so that a terminal only scans a limited frequency band, and energy waste caused by full-frequency-band blind scanning is fundamentally avoided; in a dense urban scene, signal interruption is caused by high-rise buildings, and a traditional terminal needs to repeatedly scan to maintain connection, however, a predictive scanning mechanism of the method can activate scanning in advance before signal attenuation and reduce response delay, so that a power consumption curve is smoothed, and a power consumption peak value caused by sudden switching is avoided; secondly, the energy consumption perceptual sorting mechanism dynamically evaluates the power consumption performance of the candidate satellites through historical data and context features, and preferentially selects low-energy-consumption options, so that the scanning process is more targeted.

The invention relates to a communication network base station deployment method and system based on a bilevel programming model. The communication network base station deployment method based on the bilevel programming model comprises the following steps: generating a plurality of alternative measurement and control stations in a discretization manner in a station distribution area according to a preset station distribution area and a satellite elevation angle threshold value; based on ephemeris data of a target satellite, calculating a visible time window between each alternative measurement and control site and the target satellite, and generating a visible arc segment set; based on a genetic algorithm, M measurement and control stations are iteratively selected from the alternative measurement and control stations to serve as a station combination, and M is a preset station distribution number; according to the communication network base station deployment method and system based on the bilevel programming model, the alternative stations are generated at the grid points by leaving the station distribution area, and the station distribution problem is converted into the permutation and combination problem for selecting the stations. And a nested genetic algorithm is applied to finish specific selection of sites.

The present invention relates to a system for providing power save while transmitting ephemeris data from satellites to telephones / user devices, and reducing the signalling load created by system information.

The invention provides a method and a device used in a node for wireless communication. The method comprises the following steps: a first node determines propagation time delay according to a first parameter; and compensating the sending time of the first data in advance according to the propagation time delay. Wherein the first parameter comprises at least one of the following information: position information of the first node, ephemeris information of a service satellite, public timing advance, parameter effective time, reference signal sending time or an identifier of a track section where the satellite is located.

The present application relates to the field of wireless communications. Provided are a Doppler frequency shift compensation method and apparatus, and a device and a storage medium. The method comprises: acquiring ephemeris information of a satellite; on the basis of the ephemeris information and a first frequency shift value which is estimated using a beam position center, compensating for a synchronization signal block (SSB) within a beam position, and sending a pre-compensated SSB to a terminal; and then, on the basis of a second frequency shift value, which has been updated via interpolation, compensating for an uplink signal and a downlink signal within the beam position, and sending a pre-compensated downlink signal to the terminal. A terminal can perform Doppler frequency shift compensation without relying on GNSS location information, thereby reducing the cost and usage power consumption of the terminal, decreasing the number of times that the terminal performs frequency sweeping in an initial access stage, and shortening the latency for the terminal to access a cell.

The embodiment of the invention provides a bridge monitoring satellite data quality control method based on signal-to-noise ratio grid comparison, and belongs to the technical field of satellites. The method comprises the following steps: carrying out pseudo-range single-point positioning calculation according to an observation value file and a broadcast ephemeris file to obtain observation data of each satellite; performing grid division on the satellite sky map according to a preset elevation angle interval and an azimuth angle interval to obtain a standard grid; on the basis of a standard grid, independently stacking observation data of each observation station to obtain a signal-to-noise ratio grid model corresponding to each observation station; performing preferential fusion according to the signal-to-noise ratio grid models of all the observation stations to obtain a high-quality grid model; performing data comparison on the signal-to-noise ratio grid model of each observation station and the high-quality grid model to obtain an available data area of each observation station; and performing quality control on the current observation data according to the available data area to obtain high-quality data. According to the invention, the observation area which is not subjected to interspersed shielding interference can be identified, and data quality control is realized.

A method and system for low Earth orbit (LEO) satellite multiple access and communication using grating lobes is disclosed. The method may include: acquiring ephemeris data for a plurality of LEO satellites; predicting an orbital trajectory for each of the plurality of LEO satellites based on the ephemeris data; selecting target satellites using the predicted orbital trajectories; adjusting an antenna array to form grating lobes in the directions of the selected target satellites; and transmitting and receiving data with the target satellites using the adjusted antenna array.

The invention provides an inertial navigation aided navigation positioning method and system, and the method comprises the steps: calculating the coordinate of each navigation satellite in an ECEF coordinate system according to the satellite ephemeris of a satellite navigation system; according to the navigation satellite coordinate and the inertial navigation system positioning result, the azimuth angle and the pitch angle of the navigation satellite relative to the optical detection equipment under the ENU coordinate system are solved, and the navigation satellite is tracked; acquiring star maps collected by the optical detection equipment, matching the star maps through a star map recognition algorithm, resolving a coordinate transformation matrix between two continuous frames of star maps, and recognizing fixed stars and satellites in the star maps based on the transformation matrix; converting the identified fixed star in the field of view into an ECEF coordinate system, calculating an observation angular distance between the fixed star and the satellite, and calculating a satellite observation vector in the ECEF coordinate system according to the observation angular distance; and performing error correction on the positioning result of the inertial navigation system based on the satellite observation vector. Through the scheme, the positioning precision of the inertial navigation system can be improved, and the influence of interference deception signals is reduced.

The invention provides a railway Beidou satellite signal simulation method and system based on artificial intelligence. The method comprises the steps of obtaining geographic data corresponding to a railway simulation line and ephemeris data corresponding to simulation time; through statistical analysis of geographic data, geographic features such as geometric features, terrain categories, geotechnical engineering parameters, geologic structure parameters, stratigraphic structure parameters and ground feature distribution features of the terrain are obtained; input of a pre-trained artificial intelligence model is obtained based on the geographic features and ephemeris data, so that multi-dimensional analog signal parameters are obtained; and performing navigation message filling by using the ephemeris data to generate a navigation message, and generating a Beidou satellite simulation signal based on the navigation message and the multi-dimensional simulation signal parameters. According to the invention, efficient, accurate and intelligent analog signals can be generated.

The invention discloses an earth-moon translation point orbit spacecraft formation relative motion configuration design and control method, and belongs to the technical field of spacecraft orbit dynamics and control. The method comprises the following steps: firstly, constructing a double-layer dynamic model consisting of a circular restrictive three-body problem model and a high-precision ephemeris model, and defining an orbit amplitude difference and a phase difference as configuration parameters; then, according to different track amplitude difference and phase difference combinations, three types of natural relative motion configurations are set, a periodic track is rapidly generated under a circular restrictive three-body problem model, and multi-circle correction is conducted through a high-precision ephemeris model and two-stage multiple targeting; a hierarchical constraint model is established for a controlled task surrounding a fixed position, a plane and a space, and a control pulse is solved by adopting a two-stage optimization strategy. According to the method, efficient design and stable control of formation configuration in a complex dynamic environment are realized, and the method is suitable for various translation point orbit tasks.

Techniques for supporting non-terrestrial fronthaul network architectures are provided. In one example, a wireless network includes: a satellite comprising a radio unit; a satellite gateway in communication with the satellite; and a distributed unit located on Earth and in communication with the satellite gateway. Using ephemeris data for the satellite and the location of the gateway, maximum and minimum distances between the gateway and the satellite are determined for a time period when the satellite will be in line-of-sight communication with the satellite gateway. Based on the maximum and minimum distances, maximum and minimum propagation times for signals exchanged between the satellite and the gateway during the time period are determined. Using the maximum and minim propagation times, the distributed unit coordinates uplink and downlink transmission windows with the radio unit.

The invention discloses a satellite access method and device, and the method comprises the steps that a terminal device obtains current attitude data, current position data, current antenna pattern data, current ephemeris data and current shielding data of the terminal device, the current ephemeris data comprises ephemeris data of M satellites, and M is an integer greater than 0; searching a target satellite in the M satellites and determining first attitude data according to the current attitude data, the current position data, the current antenna pattern data, the current ephemeris data and the current occlusion data, the first attitude data being a first angle of communication between the terminal device and the target satellite; and accessing the target satellite based on the first attitude data. According to the invention, the satellite can be accessed under the condition that the satellite moves at a high speed, and the transmission time delay is reduced.

Disclosed in the present application are a satellite access method and apparatus, which are applied to the technical field of communications. The method comprises: a terminal device acquiring the current attitude data, the current location data, the current antenna pattern data, the current ephemeris data and the current occlusion data of the terminal device, wherein the current ephemeris data comprises ephemeris data of M satellites, M being an integer greater than 0; on the basis of the current attitude data, the current location data, the current antenna pattern data, the current ephemeris data and the current occlusion data, searching for a target satellite among the M satellites, and determining first attitude data, wherein the first attitude data is a first angle at which the terminal device communicates with the target satellite; and on the basis of the first attitude data, accessing the target satellite. By means of the present application, it is possible to access a satellite when the satellite moves at a high speed, thereby reducing the transmission delay.

The invention relates to an IRNSS navigation signal simulation generation method and system based on parameter compensation, and the method comprises the steps: receiving original signal data outputted by an IRNSS navigation receiver, and receiving a target machine position coordinate and a velocity vector; analyzing the navigation message to extract ephemeris parameters, and calculating the real-time position and velocity vector of the satellite; calculating a Doppler frequency compensation value and a pseudo code time delay compensation value; according to the pseudo code time delay compensation value and a preset target simulation coordinate, modifying a signal emission time field in the navigation message, generating a simulation navigation message frame, carrying out forward error correction coding processing, generating a coding symbol sequence, and carrying out modulo-two addition operation on the coding symbol sequence and a pre-generated PRN pseudo code sequence to obtain a baseband spread spectrum signal; generating an intermediate frequency carrier signal according to the Doppler frequency compensation value and the carrier phase; and modulating the baseband spread spectrum signal to the intermediate frequency carrier signal, and outputting an intermediate frequency analog signal. According to the invention, the concealment of signal simulation and the success rate of capturing the analog signal by the target receiver can be improved.

Techniques for supporting non-terrestrial fronthaul network architectures are provided. In one example, a wireless network system includes: a satellite comprising a radio unit; a distributed unit located on Earth that manages the radio unit; and a satellite gateway in communication with the distributed unit and the satellite. The satellite gateway is configured to: receive ephemeris data for the satellite; initiate a sequence of clock synchronization transmissions between the radio unit and the satellite gateway; and determine, using the ephemeris data and a location of the satellite gateway, a first propagation time for a first clock synchronization transmission and a second propagation time for a second clock synchronization transmission. Based on the propagation times, the satellite gateway generates and transmits a clock synchronization correction factor that the radio unit will use to determine an offset between clock signals of the radio unit and the distributed unit.

The invention discloses an NTN condition switching method based on dynamic elevation weighting, and belongs to the technical field of wireless communication, and the method comprises the steps: obtaining D1 / T1 event configuration information and satellite ephemeris of a service satellite and a target satellite from an NR network; the position of the user equipment is obtained, and satellite elevation angles of the service satellite and the target satellite are calculated in combination with satellite ephemeris; acquiring the satellite signal quality RSRP of the service satellite and the target satellite, and performing dynamic weighting based on the satellite elevation angle, the satellite type and the path loss; and performing A3 event verification according to the position of the user equipment, the dynamic weighting result and the D1 / T1 event configuration information, and if an A3 event is satisfied, initiating a process of switching to a target satellite. On the basis of a D1 / T1 event, a switching decision is optimized by combining dynamic elevation weighting with a satellite type and path loss characteristics, the limitation of pure position / time triggering is solved, and the switching effect is improved.

A non-terrestrial radio network node receives, and transmits to a user equipment, ephemeris system information block priority configuration information. The non-terrestrial node determines parameter value change(s) corresponding to an upcoming ephemeris system information block occasion group with respect to a previous / preceding occasion group. The non-terrestrial node assigns, and transmits to the user equipment, an assigned priority, corresponding to the upcoming group, that is based on the determined parameter value change(s) or a rate of change corresponding thereto. From the priority configuration information, the user equipment determines a worst-case parameter value(s) of parameter range(s) corresponding to the assigned priority. The user equipment may determine to avoid receiving updated ephemeris information via an upcoming group occasion if the worst-case parameter value(s) does / do not exceed a configured corresponding asynchronization criterion and may instead transmit uplink traffic during upcoming group occasions.

A communication method and a related apparatus. In the method, on the basis of a reference signal reception timing difference between a first cell and a second cell, ephemeris information of a first satellite and ephemeris information of a second satellite, a terminal may calculate position information of the terminal. In this way, for terminals that lack a GNSS positioning capability or terminals that are currently unable to acquire the positions thereof by means of GNSS signals, positioning of the terminals can be realized. In addition, the first satellite and the second satellite in the present application are communication satellites, and compared with the signal strength of GNSS signals transmitted by GNSS satellites, the signal strength of positioning reference signals transmitted by the first and second satellites in the present application is stronger. Therefore, the positioning reference signals are less susceptible to environmental interference, thereby facilitating an improvement in the accuracy of terminal positioning.