44 results about "Satellite downlink" patented technology

The invention relates to the technical field of low earth orbit satellites, and discloses a method and equipment for improving the signal-to-noise ratio of a low earth orbit satellite signal, and the method comprises the steps: carrying out the multi-dimensional signal collection and processing of a received signal of a low earth orbit satellite downlink, and obtaining a signal tensor model; executing structured decomposition based on the signal tensor model to obtain a channel factor matrix group; performing multi-stage sequential processing according to the channel factor matrix group to obtain low-orbit satellite channel state information; inputting the low-orbit satellite channel state information into an interference identification module for feature extraction and interference type analysis to obtain an interference type and probability distribution thereof; performing multi-dimensional adaptive filtering on the received signal to obtain a target signal; and performing modulation coding and beam forming parameter joint optimization on the target signal and the low-earth-orbit satellite channel state information to obtain a low-earth-orbit satellite communication link, thereby solving the problem of large fluctuation of the signal-to-noise ratio in a satellite rapid moving scene, and realizing balance of power efficiency and anti-interference performance at the same time.

The invention discloses a method for aggregating ocean buoy data, which comprises the following steps of: establishing a space-time correlation model according to the spatial distribution density of buoy clusters and the dynamic characteristics of an ocean environment, and adaptively dividing buoy groups with a data compression cooperative relationship; performing a data-related compression operation within the buoy group; constructing a transmission priority dynamic sorting engine, and calculating a dynamic weight coefficient; performing hierarchical packaging processing on the differential coding data, distributing enhanced forward error correction coding resources for high-priority data, and reserving redundant transmission time slots; the method comprises the following steps: receiving a hierarchical data packet through a low-orbit satellite and executing on-satellite preprocessing, reconstructing an original data stream by using a distributed decoder, and meanwhile, fusing multi-dimensional space-time related data to generate an aggregated data product; and finally, the aggregated data product is transmitted to a ground data center through a satellite downlink. According to the invention, uplink data volume is reduced, disaster monitoring timeliness is improved, ground station processing load is reduced, and system environment adaptability is enhanced.

The invention provides a low-orbit navigation enhanced satellite orbit and clock error integrated determination method, which comprises the following steps that: a low-orbit navigation enhanced satellite carries a GNSS (Global Navigation Satellite System) receiver, can receive a multi-system GNSS satellite navigation signal and can issue a navigation enhanced signal at the same time, a downlink signal and a satellite-borne GNSS receiver clock share the same source, and a deviation exists between the clock error and the clock error of the satellite-borne receiver; the satellite-borne observation data of the low-orbit satellite, the GNSS of the ground station and the observation data of the low-orbit satellite are fused, an observation model for fusion processing is given, and the orbit of the low-orbit navigation enhanced satellite, the receiver clock error and the downlink signal time delay deviation are integrally determined. Unified adjustment and parameter joint calculation of satellite-borne and downlink observation values of the low earth orbit satellite are realized.

The invention discloses a multi-mode joint information source channel coding system for satellite-ground semantic communication. The multi-mode joint information source channel coding system comprises a joint information source channel coder and a decoder, the encoder is used for sequentially performing feature extraction, feature fusion, data cutting and phase modulation operation on input multi-modal data to generate a transmitting signal, and transmitting the transmitting signal to a ground base station through a channel; and the decoder is used for sequentially performing real and virtual part separation, data expansion, feature extraction and modal data recovery operation on the received signal so as to reconstruct multi-modal data. According to the system, public semantic information among multi-modal data can be mined, the time-varying low-signal-to-noise-ratio channel characteristics of a satellite downlink are combined, the information bottleneck theory highly related to data reconstruction quality is used as guidance to optimize a coding space, complex field transmission signals with the high compression ratio are generated in a self-adaptive mode, and the multi-modal multi-domain transmission signals are obtained. The reconstruction quality of the multi-modal data can be ensured, and the bandwidth and the energy consumption overhead of satellite communication can be remarkably reduced.

The invention belongs to the technical field of low earth orbit satellite communication, and particularly relates to a low earth orbit satellite large-scale hopping beam efficient scheduling method and system based on an interference approximation model. According to the method, downlink beam resources of a multi-beam low-orbit satellite are used as research objects, and the problems that in existing large-scale and long-period beam scheduling, the performance evaluation complexity of a beam scheduling strategy is high, and the complexity of a beam scheduling algorithm is rapidly increased along with the increase of variable dimensions are solved. The invention provides low-complexity design and application based on an inter-beam interference approximation model, the inter-beam interference approximation model is introduced from a probability perspective, a rapid performance evaluation method is designed, and a low-complexity scheduling method is designed for two typical low-orbit satellite beam scheduling problems by utilizing an introduced beam activation intensity concept.

The invention discloses a Starlink satellite downlink signal timing synchronization method based on deep learning, and the method comprises the steps: firstly carrying out the segmentation cross-correlation preprocessing of a received signal, and generating a two-dimensional real number feature map with significant spectral line features; then, an improved SS-YOLOv9 network model is constructed and trained, according to the model, in a YOLOv9 infrastructure, a lightweight SimAM saliency attention module is embedded into a backbone network to enhance feature separability, an FAF adaptive feature fusion module is introduced into a path aggregation structure of a neck network to optimize multi-scale feature fusion, and the feature fusion is optimized; precise positioning is realized by adopting a decoupling detection head and a coordinate attention mechanism; and finally decoding bounding box coordinates output by the network into timing synchronization points in original signals. According to the method, the problem that the performance of a traditional method is sharply deteriorated in a severe channel environment is effectively solved, and the method has high precision, high robustness and excellent environmental adaptability.

The application provides a satellite-under device random access method, a satellite, a terminal device and an electronic device. The method comprises the following steps: the satellite respectively sends a power allocation range to at least one terminal device; the terminal device receives the power allocation range sent by the satellite; a check value is determined according to any uplink transmission power in the power allocation range and a current access frequency initiated by the terminal device; the check value is sent to the satellite; the satellite receives the check value respectively sent by at least one terminal device; a device access table is determined according to at least one check value; the device access table is respectively sent to at least one terminal device; the terminal device receives the device access table sent by the satellite; whether the terminal device accesses the satellite is determined according to the device access table. The method can effectively prevent a malicious terminal from forging a legal identity to initiate a random access with multiple frequencies, improve the access rate of a legal terminal, and improve the security performance of satellite-under device random access.

The invention provides a high-mobility platform random access method and system for a low-orbit satellite data chain, and the method comprises the steps: taking a satellite ephemeris and platform navigation information as initial guidance, receiving and analyzing a satellite downlink signal, and carrying out the joint estimation to obtain a space-time frequency parameter; based on the estimated timestamp as a time reference of a frequency hopping pattern, driving a local frequency hopping sequence generator, predicting and verifying the current frequency hopping pattern, and performing frequency offset correction according to the estimated Doppler frequency offset; and in response to successful verification of the frequency hopping pattern, constructing a pre-compensated uplink and starting a frequency hopping pattern tracking loop for fine tuning of the time-space-frequency parameter and the frequency hopping pattern phase, so that the user accesses the low-orbit satellite data link at random and enters steady-state communication. The time-space-frequency alignment problem and the time-varying frequency hopping pattern capturing and tracking problem are synchronously solved, and rapid, reliable and anti-interference random access of the high-mobility platform is achieved.

The invention discloses a monopulse phase comparison tracking signal processing method based on a digital beacon receiver, and relates to the technical field of radio orientation, and the method comprises the steps: carrying out the antenna pointing deviation analysis of a shipborne communication-in-motion antenna according to the predicted ship attitude information in a preset time window, and obtaining a predicted pointing deviation angle sequence; carrying out feature extraction to obtain a directional deviation trend feature, and determining the resolving complexity of four paths of radio frequency signals of the shipborne communication-in-motion antenna; dynamically configuring the phase comparison algorithm processing precision, the filtering processing mode and the signal compensation mechanism of the digital beacon receiver, and generating an adaptive signal resolving process; and according to an adaptive signal resolving process, resolving the continuous wave satellite downlink beacon signal in the preset time window through a digital beacon receiver to obtain a monopulse phase comparison tracking signal, and regulating and controlling the orientation and pitching of the shipborne communication-in-motion antenna in real time. According to the invention, the technical problem of poor radio orientation effect in the prior art is solved.

The application provides a satellite navigation signal abnormal reason analysis method, establishes a satellite signal transmission channel combination distortion model, generates an ideal signal, and constitutes a combination distortion distortion model library; collects measured satellite downlink signal data to obtain a measured signal quality evaluation result, compares and analyzes the measured signal quality evaluation result with a set evaluation index, finds out a group of the most matched evaluation result data and pre-stored data in the distortion model library; and according to the best matching relationship between the measured satellite signal evaluation result and the distortion model library data, obtains the corresponding satellite signal transmission channel distortion condition. The application can efficiently and credibly give an abnormal signal specific reason analysis result, helps a navigation system to quickly lock the signal abnormal reason, and provides valuable reference and important support for channel distortion compensation and stable operation of the system.

The application discloses a low-orbit satellite navigation enhancement and ground CORS cooperative system and relates to the technical field of satellite navigation positioning, which comprises a space segment, a ground segment and a user segment; the space segment comprises a low-orbit satellite and is used for broadcasting navigation enhancement signals; the ground segment comprises an enhanced CORS network and a star-ground cooperative control center; each ground reference station simultaneously receives GNSS signals and navigation enhancement signals and generates observation data; the star-ground cooperative control center performs precise orbit determination based on low-orbit satellite downlink data and observation data, and uploads star-ground calculation results to the low-orbit satellite to update the generation parameters of the navigation enhancement signals; the user segment comprises a hybrid enhancement receiver, which is used for receiving GNSS signals, navigation enhancement signals and differential data and performing multi-source fusion positioning calculation. The application can improve the low-orbit satellite orbit determination precision, shorten the user initialization time, expand the service coverage, reduce the system construction cost and enhance the integrity guarantee capability.

Embodiments of the present disclosure are directed to systems and methods for enhanced multi-satellite downlink connectivity. Each of two or more extraterrestrial base stations communicate data in a downlink to a single user equipment (UE). Encoding each downlink with a different and orthogonal code permits the re-use of at least partially overlapping frequency resources without intra-channel interference. The separated data streams can be used either to provide additional redundancy when the same data is communicated on each stream or to increase throughput when at least partially different data is communicated on each stream.

The application provides a navigation satellite on-orbit operation main and backup clock frequency drift rate optimal transfer method, comprising: combining satellite-ground two-way ranging observation data, using satellite-ground two-way comparison method to calculate a plurality of main clock difference parameters; through on-orbit navigation satellite downlink engineering telemetry data, obtaining the clock difference parameters of the hot backup clock relative to the main clock; calculating a plurality of hot backup clock difference parameters; in the main and backup clock following state, the phase and frequency of the hot backup clock are equal to the phase and frequency of the main clock and change synchronously with time; after the on-orbit navigation satellite is stably operated, the frequency drift rate of the satellite clock difference data is a constant, the hot backup clock difference parameters are uploaded to the on-orbit navigation satellite storage; when the on-orbit navigation satellite autonomously monitors that the main clock and the hot backup clock are switched, the stored hot backup clock difference parameters are directly and autonomously called to replace the main clock difference parameters as the satellite clock difference data, the satellite clock difference data after switching is compensated, and the frequency drift rate of the satellite clock difference data is corrected.

The application discloses a satellite downlink wireless transmission method, device and equipment and a storage medium, and belongs to the technical field of wireless communication. The method comprises the following steps: acquiring target statistical channel state information between a satellite and a user terminal; determining a target problem by using the target statistical channel state information, wherein the target problem is to maximize the ergodic achievable rate of the user terminal under the constraints of satellite transmission power and unmanned aerial vehicle relay power; updating a transmission covariance matrix and a relay amplification matrix by using an alternating optimization algorithm on the basis of the target problem, so as to obtain an optimized transmission covariance matrix and an optimized relay amplification matrix; and transmitting a signal to the user terminal through the unmanned aerial vehicle relay based on the optimized transmission covariance matrix and the optimized relay amplification matrix. The technical scheme provided by the application can realize downlink wireless transmission in an unmanned aerial vehicle assisted satellite communication system by using statistical channel state information.

This invention relates to the field of satellite navigation system technology and proposes a method for monitoring the integrity of a satellite navigation system. The method involves the satellite navigation system performing the following actions: receiving bidirectional measurement data from an inter-satellite link and correcting errors; using predicted orbit and predicted clock bias parameters to reduce the bidirectional observation data of the inter-satellite link to determine a first inter-satellite geometric distance and a first relative clock bias; calculating a second inter-satellite geometric distance and a second relative clock bias based on satellite navigation messages; subtracting the second inter-satellite geometric distance and the second relative clock bias from the first inter-satellite geometric distance and the first relative clock bias, respectively, to determine geometric distance residuals and relative clock bias residuals; receiving pseudorange data and phase data of the satellite downlink navigation signal from a ground monitoring station and correcting errors; using satellite navigation messages to calculate the equivalent distance error of the navigation satellite; and determining the integrity status of the satellite payload based on the geometric distance residuals, relative clock bias residuals, and the equivalent distance error of the navigation satellite.

The invention relates to a high-efficiency high-capacity space-based Internet of Things access method, which comprises the following steps of: firstly, assisting a user terminal to perceive a link state by using an on-satellite demodulator, and then dynamically broadcasting the working state of an uplink demodulator through a satellite downlink modulator, so that the link throughput rate of uplink random access is improved. According to the invention, the global terminal position management characteristic of the service operation center of the constellation system is utilized to form the dynamic terminal random sending probability parameter under the coverage of the satellite beam, and the dynamic terminal random sending probability parameter is broadcasted to the user terminal in real time through the satellite, so that the data sending probability parameter of the terminal is dynamically changed, and the throughput rate of user link random access is optimized from the system level.

The invention relates to the technical field of wireless communication, and discloses a single-antenna terminal time-varying arrival angle prediction method based on equivalent and prior information, which comprises the following steps: establishing a motion model of a satellite relative to a terminal, and determining model parameters to be estimated; on the basis of displacement equivalence, signals sent by a satellite at different moments and different positions and received by a fixed single-antenna terminal are equivalent to signals sent by the satellite at the same moment and received by a virtual array antenna terminal, and a single-antenna equivalent array manifold matrix is constructed; according to the constructed equivalent array popular matrix, processing a received signal by using a MUSIC algorithm to obtain signal arrival angle information; performing model fitting on the estimation results of the plurality of different moments and an undetermined satellite motion model through a least square fitting algorithm to obtain a final satellite motion model, and retaining or updating the arrival angle prediction model to obtain a new prediction model of a satellite service period; according to the method, the arrival angle estimation capability of the single-antenna Internet of Things terminal on the high-dynamic satellite downlink signal is improved.

The invention provides a satellite downlink hidden transmission method based on an MIMO (Multiple Input Multiple Output) technology. According to the method, satellite hidden transmission in a mobile scene is supported, the processing complexity of a multi-layer weighted fractional order Fourier transform modulation signal method is reduced, and the real-time performance of synchronous distribution is improved; according to the scheme of the invention, a satellite counts state information by using a slowly varying channel between the satellite and a ground station, dynamically calculates a hidden processing matrix according to a minimum mean square error criterion, and pre-processes to-be-transmitted data in real time, so that the anti-interception and anti-cracking capability of downlink transmission data is improved; a hidden processing matrix is introduced into a satellite transmitting end, mass data are mapped to multiple antennas in parallel to be transmitted out at the same time after space-time hidden processing, and the transmission rate of a system and the anti-interception capability of the data are improved by utilizing spatial multiplexing gain provided by an MIMO technology under the condition that the frequency is the same and the transmitting power is not increased.

A non-terrestrial radio network node may determine a count, or a number, of user equipment being served by, or that are connected to, the node via at least one non-terrestrial beam. The node may analyze the count, or number, with respect to at least one power increase criterion or at least one power decrease criterion. With respect to a baseline / default power allocation, the node may increase or decrease transmission power allocated to a particular non-terrestrial beam if the beam is determined to serve a number of user equipment that exceeds a configured power increase criterion or that is less than a configured power decrease criterion, respectively. The node may increase or decrease transmission power allocated to a non-terrestrial beam according to a configured power change step value. Based on counts of user equipment served by different beams, the node may determine to allocate different transmission power amounts to different beams.

The application relates to a kind of on-orbit calibration methods of low-orbit communication satellite downlink phased array antenna based on CDM, belonging to the field of satellite testing technology.The method takes the pointing measurement and calibration of low-orbit communication satellite downlink phased array antenna as input, and realizes the measurement and calibration of the beam pointing of the downlink phased array antenna through the test and data processing of multiple beams EIRP of the downlink phased array antenna.The method has the functions of calibration signal generation, beam EIRP test, beam three-dimensional directional diagram reconstruction, pointing deviation measurement and beam pointing adjustment.Simulation experiments show that the calibration method designed by the application can effectively reduce the beam pointing deviation of low-orbit communication satellite downlink phased array antenna.

The invention discloses a communication and navigation integrated implementation system and method of a low earth orbit satellite Internet of Things system. The system comprises a low earth orbit satellite module, a ground terminal receiving module, a positioning and parameter calculation module, an access control and compensation module and an uplink communication link establishment module. A positioning measurement signal is introduced into a satellite downlink NB-IoT (Narrow Band Internet of Things) or eMTC (Enhanced Machine Type Communication) signal, so that a ground terminal can simultaneously complete positioning data acquisition, optimal satellite selection and time and frequency compensation of an uplink signal, thereby effectively solving the problems of low access efficiency and difficulty in synchronization and compensation in the prior art. According to the invention, deep fusion of communication and navigation is realized, the access speed and reliability of the low-orbit satellite Internet of Things system are improved, and the method has good application prospect and popularization value.

The application discloses a resource allocation method based on high-orbit satellite demand and low-orbit satellite rate, and is suitable for a downlink orthogonal frequency division multiplexing satellite communication system in which high-orbit satellites and low-orbit satellites coexist. A carrier and power joint allocation model is established based on high-orbit satellite downlink communication demand and maximization of low-orbit satellite downlink rate. The carrier and power joint allocation model is converted into a continuous variable model by using a large M method and a concave-convex process method. A non-convex optimization objective function and constraint condition of the continuous variable model are solved by using the concave-convex process method, and the optimal values of the carrier and power are obtained. The low-orbit satellite downlink rate is maximized under the premise of guaranteeing high-orbit satellite communication demand. Compared with existing methods such as fixed access and branch and bound method, the application method can reduce complexity and improve the low-orbit satellite downlink rate.

The invention discloses a remote sensing satellite downlink data instant service method and system and electronic equipment, and relates to the technical field of remote sensing information engineering or other related technical fields. The method specifically establishes remote sensing information instant service integrating satellite downlink data access, satellite downlink data instant geometric positioning, target information rapid extraction and remote sensing information active service, and comprises the following steps: accessing received remote sensing satellite downlink data, and obtaining the remote sensing satellite downlink data; carrying out geometric correction on the satellite downlink data by adopting a multi-satellite image collaborative uncontrolled geometric positioning strategy to obtain instant geometric positioning data; inputting the real-time geometric positioning data into a deep learning model of predetermined ground object target identification to obtain specific target thematic information; and intelligently pushing a corresponding image content text description corpus generated based on the instant geometric positioning data and the target thematic information to the user, and optimizing an image cognition calculation model by using information fed back by the user, thereby improving the precision of a remote sensing data information service product.

The invention provides a plasma detection data calibration method and device, a medium and electronic equipment. The method comprises the following steps: acquiring a downlink plasma data sequence of a satellite; performing noise separation processing on the plasma data sequence; based on a preset correlation model of plasma data and space environment parameters, according to the space environment parameters when the plasma data sequence is collected, determining target reference values corresponding to the plasma data at all moments of the plasma data sequence; and based on the plasma data of the plasma data sequence at each moment and the target reference value, performing calibration processing on the plasma data to obtain calibrated plasma data. According to the invention, high-quality conversion from original, noisy and environment-interfered observation data to calibration data is realized, and a data foundation is laid for subsequent establishment of an accurate plasma environment model and reliable space weather forecast.

This invention relates to an uplink power control method and control device for a satellite communication system. The uplink power control method for the satellite communication system includes: S100, acquiring the downlink signal strength P0 of the satellite under clear sky weather conditions; S200, at t i Continuously measure the signal strength P of the satellite downlink under severe weather conditions i S300, based on P0 and P i Calculate the downlink signal attenuation value Ad i S400 divides the uplink frequency band into multiple sub-bands, according to Ad... i Calculate the signal attenuation value Au for each uplink sub-band. ki S500, according to Au ki Adjust the compensation attenuation value A of the corresponding sub-band ki This can effectively reduce uplink power compensation errors in satellite communication systems and improve the control accuracy of uplink power.

The invention discloses a Ka-frequency-band rain-attenuation-resistant uplink power rapid compensation method based on AGC, and relates to the field of communication and measurement and control. The system is composed of a satellite, a ground station receiving link, a ground station transmitting link, baseband equipment and a ground station monitor. According to the invention, a relation model of downlink signal rain attenuation and uplink signal power compensation is created by using the change of the satellite downlink signal receiving AGC level, and when the downlink signal changes due to the influence of the rain and snow antenna, the ground station can monitor the change condition in real time, measure and calculate the uplink power compensation parameter in real time and adjust the uplink power, so that the power compensation accuracy is improved. And the uplink of the satellite is always in a good working state. According to the invention, the problem that the uplink of the Ka frequency band of the ground station is influenced or interrupted in rainy and snowy days can be solved. According to the invention, rapid compensation adjustment of uplink power can be realized, the adjustment precision is high, the adjustment time is controlled below the second level, and the method also has the characteristics of practical and concise design scheme, strong universality, reliable control mode, high timeliness and the like.

This invention discloses an optimization method for a terrestrial integrated planetary-terrestrial cellless network, belonging to the field of wireless communication. The invention constructs an optimization problem for a terrestrial integrated planetary-terrestrial cellless network with maximum sum rate (MSR) and maximum minimum fairness (MMF) as optimization objectives. By adopting maximum sum rate as the optimization objective, spectral efficiency is maximized while meeting the TU / ES service quality requirements of each terminal user. By employing maximum minimum fairness in beamforming design, the fairness of the terrestrial cellless network is guaranteed, maximizing the total rate of the satellite downlink multicast network. The stability of beamforming is ensured by introducing constant modulus constraint CR1, and service fairness among users is guaranteed by fairness constraint CR2. This invention transforms the MSR-based joint precoding problem into an equivalent quadratic constrained quadratic programming (QCQP) problem through fractional programming, alternating optimization, and successive convex approximation methods. An ADMM-based algorithm is used to optimize the terrestrial integrated planetary-terrestrial cellless network, significantly reducing the computational complexity of the optimization.

The application discloses a kind of low-orbit satellite signal frequency estimation method and system based on Kalman neural network, mainly solve the problem of low frequency estimation precision and poor robustness in non-cooperative high dynamic scene in prior art.The scheme is: initialization parameter, generate carrier wipe-off signal to wipe off received signal carrier, calculate the remaining frequency estimation value, and obtain the measurement value by observation;Build an end-to-end network model including high dynamic feature extraction unit, two-layer gated recurrent unit, self-attention fusion unit and constrained output unit;The network model is supervised and trained using the measurement value and state estimation increment;The measurement value and state estimation increment are input into the trained network, and the Kalman gain prediction value is output, the state posteriori estimation value at the current time is calculated as the input for the next time cycle update, to realize continuous online high-precision estimation of satellite signal frequency.The application can realize real-time, robust and high-precision estimation of low-orbit satellite downlink signal frequency, and can be used for non-cooperative satellite navigation and positioning.

The invention discloses a downlink data sending system for space navigation, which starts from improving the efficiency of a measurement and transmission integrated downlink channel, adopts an FPGA (Field Programmable Gate Array) to realize a data scheduling technology, completes the distribution of downlink caches of five kinds of data according to a data address specified by CPU (Central Processing Unit) software, and opens the real-time read-write address of each cache to the CPU software. And meanwhile, the FPGA provides five data downlink proportion control registers for the CPU software, and the data downlink proportion is controlled by the CPU software, so that the functions of flexible configuration and balanced transmission of telemetering and data transmission downlink are realized, the consumption of a satellite hardware interface on computer FPGA interface resources is reduced, and the utilization rate of a whole satellite downlink channel is improved.