499 results about "Constellation" patented technology

The deep joint source channel coding method comprises the following steps: a sending end obtains a first semantic feature of a first image, and performs constellation mapping modulation on the first semantic feature to obtain a first initial constellation point; the sending end extracts semantic information of the first initial constellation point, generates a rotation angle corresponding to the semantic information, and rotates the first initial constellation point according to the rotation angle to obtain a first rotation constellation point; the sending end generates a real part interleaving matrix and an imaginary part interleaving matrix based on the first rotating constellation point and the real part and the imaginary part of the channel state information, resorts the real part and the imaginary part of the symbol sequence respectively and then recombines the real part and the imaginary part into a complex signal to obtain a first interleaving signal; the sending end transmits the first interleaved signal to a receiving end through a fading channel, and the receiving end receives a second interleaved signal; the receiving end performs semantic reconstruction decoding on the second interleaved signal to obtain a second image; or, the receiving end performs semantic classification decoding on the second interlaced signal to obtain a second image category.

The invention relates to the technical field of large-scale constellation task planning, in particular to a large-scale constellation efficient cooperative task planning method based on hierarchical reinforcement learning, which comprises the following steps: constructing a large-scale constellation task planning model; performing end-to-end collaborative planning on a multi-satellite task allocation problem and a single-satellite task scheduling problem based on hierarchical reinforcement learning, including task allocation based on Monte Carlo tree search and task scheduling based on Transform architecture; setting a task distribution model and a task scheduling model, and inputting the task information into a task distribution module to obtain a distribution result; and calculating task scheduling information of each satellite according to the distribution result, inputting the task scheduling information into a task scheduling module, and obtaining a scheduling result through the task scheduling module. According to the method, efficient planning of large-scale constellation tasks is realized, the optimization target can be coupled, the solution complexity is reduced, the global optimality of the solution is ensured, and the solution efficiency is improved.

The invention provides a low-orbit forward scattering detection method and system and a medium. Comprising the steps that a low-orbit forward scattering detection model based on Walker constellation configuration is constructed, each satellite and a receiver form a detection unit, and after an aerial target is excited by a radiation signal of a satellite group {}, if the kth detection unit meets a bistatic angle, according to the Cavalieri principle and a signal-to-noise ratio threshold condition, the kth detection unit meets the bistatic angle; determining a real effective coverage ratio meeting a geometric constraint condition and a detectable elevation threshold meeting a power constraint condition; an effective detection window is formed in the shadow cone unit based on the true effective coverage ratio and the detectable elevation threshold, and low-orbit forward scattering detection is performed. According to the method, the detection performance of the low-orbit forward scattering detection system under the conditions of different satellite numbers, different detection wavelengths and the like is analyzed, and theoretical support is provided for reliable airspace perception of the low-orbit giant constellation forward scattering detection system.

The invention provides a direct communication method and device based on constellations, electronic equipment and a storage medium, and relates to the technical field of satellite communication. The direct communication method based on the constellation provided by the invention comprises the following steps: acquiring position information and historical communication information corresponding to a plurality of target communication areas respectively, and determining a distribution relationship among the plurality of target communication areas based on the plurality of pieces of position information; determining a target satellite screening criterion based on the distribution relationship and the historical communication information; based on a target satellite screening criterion, screening target satellites respectively corresponding to the plurality of target communication areas and applicable beam resources corresponding to the target satellites from the plurality of satellites to be selected; and controlling the target satellite to provide a communication service for the corresponding target communication area based on the applicable beam resources and the generated communication service instruction. The direct connection communication efficiency of the constellation satellites can be improved.

In an example embodiment, a method carried out by an uncrewed aerial vehicle (UAV) may involve receiving a reference map of a cluster of charging pads from a server. The cluster may include a layout of charging pads and fiducial markers distributed across the layout, the reference map representing the layout and fiducial markers. The UAV may fly to the cluster and acquire an image of charging pads and observed fiducial markers near the charging pads. The image may capture an observed constellation of fiducial markers at apparent positions and orientations relative to the charging pads. A reference constellation of fiducial markers at reference positions and orientations relative to reference charging pads may be identified in the reference map. Identities of the reference charging pads and a match of the reference constellation to the observed constellation may be used to disambiguate a particular charging pad from among the charging pads.

The invention relates to a rapid visible time window calculation method for large-scale satellite group cooperation. The method comprises the following steps: establishing an analytic relationship between time and a satellite latitude argument based on a rapid analytic orbit model; calculating a rough moment when the sub-satellite point trajectory of the satellite intersects with the target declination circle; screening potential coverable circles in combination with satellite side sway and a field angle; for each circle, accurately calculating the positive side-looking moment of the satellite to the target by iterating the spherical geometrical relationship; and finally, by taking the moment as a reference, performing forward and backward recursion by using a high-precision model in combination with a dichotomy to determine accurate starting and ending moments of the visible window. According to the method, the defects that a tracking propagation method is high in calculation precision but high in calculation cost can be overcome, and the preprocessing efficiency of a ground or satellite-borne task planning system is improved; meanwhile, the problem of low precision in the prior art is solved, a solution is provided for satellite-borne window calculation of a large-scale satellite group cooperative task planning system, and online and high-precision calculation of single-satellite and satellite group visible windows during large-scale satellite group cooperation is realized.

A wireless communication device configured with approximation schemes utilizing functional fitting in constellation shaping is disclosed. The device is configured to obtain subintervals over which to form piecewise polynomial approximations of a plurality of terms, obtain, utilizing the piecewise polynomial approximations of the plurality of terms, an approximation of a total number of first symbol sequences over a first alphabet having a first alphabet size, each respective symbol sequence of the total number of first symbol sequences having a first symbol sequence length and a first symbol sequence energy, obtain a bit sequence having a bit sequence length, encode the bit sequence, utilizing the approximation of the total number of first symbol sequences, to a second symbol sequence over a second alphabet having a second alphabet size, the second symbol sequence having a second symbol sequence length and a second symbol sequence energy, and transmit the second symbol sequence.

The invention relates to the technical field of satellite signal processing, and discloses a multi-constellation satellite signal intelligent identification and adaptive acquisition method and system. The method comprises the following steps: performing short-time Fourier transform on a received signal to extract a frequency trajectory matrix, calculating a Doppler frequency shift rate and an acceleration, inputting a multi-task neural network in combination with modulation domain characteristics, and outputting constellation category and interference type identification results, when a low-orbit satellite is identified, a carrier frequency deviation track and uncertainty are predicted through a long-short term memory network, the frequency of a numerical control oscillator is adjusted in advance according to a prediction result, a search window and integral time are dynamically set, and corresponding anti-interference strategies are executed for different interference types. And periodically monitoring the signal quality index, and triggering strategy upgrading when the performance improvement rate is lower than a threshold value. According to the invention, the signal capture success rate and tracking stability in a multi-constellation mixed environment are improved.

In a space traffic management system (500), space traffic management devices (100) individually mounted in a plurality of mega-constellation business devices and in a debris removal business device (45) are connected to each other via a communication line (200). The debris removal device (45) performs Active Debris Removal (ADR) against debris formed by a satellite managed by a first mega-constellation business operator. The debris removal device (45) acquires real-time high-accuracy orbital information of a satellite group of a second mega-constellation business operator in a timeframe in which a debris removal satellite, during orbital descent, passes through an orbital altitude region where the satellite group of the second mega-constellation flies, the debris removal satellite passing through the satellite group while ensuring flight safety.

The invention discloses a resource scheduling optimization method for a giant constellation, relates to the technical field of satellite resource allocation of the giant constellation, solves the problem that an existing satellite resource scheduling method is difficult to give consideration to global optimization of time and energy consumption, and aims to improve the execution efficiency of a multi-satellite cooperative task and reduce energy consumption. A real satellite scheduling task is simulated and arranged to obtain satellite data and task data, an evolutionary process of a reinforcement learning guide genetic algorithm is adopted to optimize a task sequence, satellite resource allocation is performed on the optimized task sequence, time and energy consumption of the task sequence are completed, and finally normalization is performed to obtain a comprehensive index. According to the method, a task execution sequence with the minimum time and energy consumption comprehensive index is obtained, so that an optimal scheduling scheme is obtained, and the requirement of satellite scheduling under a giant constellation is met.

The invention discloses a multi-source navigation signal switching and fusion method and a navigation system thereof, and the method comprises the steps: carrying out the quality evaluation of signals from different navigation source GNSS, and determining a main navigation source based on a quality evaluation result; when the quality score of the main navigation source is lower than a preset threshold value or the GNSS observation information meets a preset switching condition, switching between the main navigation source and the standby navigation source is carried out, and smoothing processing is carried out on the new navigation solution and the old navigation solution in the switching process of the main navigation source and the standby navigation source; and performing multi-source data fusion and state estimation on the data of the navigation source GNSS, the inertial measurement unit, the geomagnetic sensor and the air pressure sensor through a filtering algorithm, and outputting a navigation result. According to the navigation system, a plurality of multi-constellation GNSS receiving chips, an inertial measurement unit, a geomagnetic sensor, an air pressure sensor and a micro-control unit are vertically interconnected in a single package through a wafer-level heterogeneous integration process. According to the invention, the positioning precision and robustness in a complex environment can be improved.

The invention discloses a multi-satellite cooperative operation method based on measurement and control link optimization, and relates to the technical field of spaceflight measurement and control and satellite communication optimization, and the method comprises the steps: obtaining the orbital elements of all satellites in a target constellation and the geographic coordinates of ground measurement and control stations, calculating the visible time windows of all satellites and all measurement and control stations, and generating a visible window matrix; constructing a link quality evaluation model to obtain a link quality index; distributing measurement and control time slots by using a weighted optimization algorithm, and generating a time slot distribution matrix; issuing a measurement and control instruction to each satellite and each measurement and control station, acquiring a link quality measured value, and comparing the link quality measured value with a link quality index to obtain a comprehensive link quality deviation value; and when the comprehensive link quality deviation value exceeds a preset threshold value, marking unexecuted measurement and control time slots in the time slot distribution matrix, and redistributing the unexecuted measurement and control time slots to generate an updated time slot distribution matrix, thereby realizing self-adaptive cooperative operation of the multi-satellite measurement and control link. According to the invention, dynamic optimal configuration of multi-satellite measurement and control resources is realized.

The invention discloses a modulation identification method for multi-modal feature fusion based on signal-to-noise ratio guidance, and belongs to the technical field of signal processing driven by artificial intelligence. In order to solve the problems that in an existing modulation recognition technology, single-mode features are not universal, noise is sensitive, performance is reduced in a low signal-to-noise ratio environment, and utilization of complementary information among modes is insufficient due to coarseness of a multi-mode fusion strategy, an original I / Q signal is converted into three modes including a time-frequency graph, a three-dimensional constellation point cloud and an I / Q time sequence; an input signal is dynamically evaluated by utilizing a pre-trained signal-to-noise ratio estimation model, the fusion weight of each modal feature is intelligently adjusted by taking an estimated signal-to-noise ratio value as guide information, adaptive weighted fusion is realized, and finally a modulation type is identified through a classifier. According to the method, the accuracy and robustness of modulation identification in a complex electromagnetic environment are effectively improved, and the method is suitable for wireless communication, frequency spectrum monitoring and Internet of Things equipment authentication.

The invention discloses a space target monitoring constellation configuration optimization method and system considering complex constraints, and belongs to the technical field of aerospace mission design and optimization. The method comprises the following steps: firstly, constructing a discrete orbit modal library meeting regression orbit dynamic resonance conditions; constructing generalized hybrid design variables consisting of integer indexes and real number fine tuning quantities on the basis of the library; establishing an optimization model taking the space volume coverage rate, the maximum revisit time and the system construction cost as targets and taking illumination, dynamics and maneuvering capability as constraints; performing rapid analysis and coarse screening on invalid links through track geometry; and finally, performing global optimization by using an improved non-dominated sorting genetic algorithm to obtain a Pareto optimal constellation configuration set. According to the method, accurate evaluation of the three-dimensional space target coverage efficiency is realized, the physical feasibility and long-term stability of a configuration scheme are ensured, and a high-dimensional multi-target optimization problem is efficiently solved.

Systems and methods are described for generating and implementing return-link satellite communications using a novel 1+N-ary constellation. The 1+N-ary constellation arranges M (e.g., 8) constellation points in a novel formation that increases their distances from each other relative to conventional M-ary modulation schemes by locating an inner constellation point centrally with respect to an I-Q plane and distributing the remaining N (i.e., M=N+1) outer constellation points radially around the inner constellation point. 1+N amplitude and phase-shift keying (APSK) modulation can be used to map symbols to the constellation. Embodiments combine the 1+N APSK modulation with additional features, such as non-Nyquist partial response (NNPR) filtering and / or state of the art low-density parity check (LDPC) coding.

The invention discloses a virtual-real combined sky-ground multi-domain heterogeneous network cooperative computing simulation system and a virtual-real combined sky-ground multi-domain heterogeneous network cooperative computing simulation method. The system comprises a heterogeneous computing power prototype subsystem, a virtual simulation subsystem, a satellite-borne general computing terminal, a programmable network simulator, a heterogeneous resource management subsystem and a simulation verification system interface. Real hardware computing power characteristics are introduced through a physical board card, large-scale expansion is realized through virtual nodes, and authenticity and large-scale performance of simulation are considered; link parameters are generated according to a high-precision orbit dynamics model, and the fidelity of sky-ground network simulation is greatly improved; based on a mixed container arrangement technology, unified management and intelligent scheduling of sky, air and ground heterogeneous resources are realized, and a powerful platform is provided for verifying an advanced cross-domain collaborative algorithm; one set of system can support various simulation verification requirements of networking routing, task unloading, distributed cooperative computing, constellation cluster management and control and the like, and the research and development cost and complexity are reduced.

The invention relates to an unmanned aerial vehicle high-precision positioning method based on micro-centimeter space low-orbit constellation and Beidou PPP-B2b fusion enhancement, and the method comprises the steps: obtaining a precise orbit correction number and a precise clock correction number of a GPS and a BDS system based on a Beidou PPP-B2b signal; calculating a precise orbit and a precise clock error of the GNSS satellite based on the precise orbit correction and the precise clock error correction; on the basis of the precise orbit and the precise clock error of the GNSS satellite, an observation value of a micro-centispace low-orbit satellite is fused, and a GNSS / LEO combined PPP observation model is constructed; and based on extended Kalman filtering, precise point positioning calculation is carried out on the GNSS / LEO combined PPP observation model, and the real-time high-precision position of the unmanned aerial vehicle is obtained. According to the invention, the real-time high-precision position of the unmanned aerial vehicle can be rapidly and stably obtained, and a reliable position reference is provided for autonomous operation of the unmanned aerial vehicle in a network-free environment.

The invention provides a large-scale low-orbit constellation topology construction method and system based on the reliable reachable distance of an optical transceiver and a storage medium, and the method comprises the steps: 1, building an inter-satellite laser link probability evaluation model based on the capturing probability of an aiming-capturing-tracking system and the motion characteristics of satellites; 2, on the basis of the inter-satellite laser link probability evaluation model, constructing a giant satellite network topology evaluation model with inter-satellite link time average stability, satellite hop count and communication time delay as core optimization targets, and outputting a globally optimized laser link connection scheme; and 3, for a laser link connection scheme, proposing a giant constellation network topology design algorithm based on a capture probability, and constructing a constellation topology by adopting a minimum unit of a space symmetric constellation. The method has the beneficial effects that the constellation topology is constructed by adopting the minimum unit of the space symmetric constellation, so that the topological structure is stabilized, the channel gain is improved, the end-to-end delay is shortened, and the average hop count and the variance of the network are reduced.

The invention discloses a dimension-level constellation disassembly transmission method based on high-dimensional constellation selective mapping, and belongs to the technical field of optical fiber communication. The method comprises the steps that a traditional high-dimensional constellation is constructed, the number of constellation points needing to be extracted is determined through an entropy limit adaptive tuning function, then needed constellation points are extracted from the traditional high-dimensional constellation, and a shaped high-dimensional constellation is obtained; performing dimension-level disassembly on the shaped high-dimensional constellation to obtain a low-dimensional constellation set; performing phase conversion on the low-dimensional constellation set, and transmitting the converted low-dimensional constellation set to a channel for transmission in a spherical coordinate And receiving the low-dimensional constellation set at a receiving end, combining and restoring the low-dimensional constellation set into a high-dimensional constellation, and performing corresponding judgment on the high-dimensional constellation to obtain bit data. Part of constellation points are selected from a high-dimensional constellation to carry out data bearing and transmission, and the Euclidean distance between the constellation points is increased to reduce the bit error rate. And a high-dimensional constellation is disassembled into a low-dimensional constellation set for transmission in the form of a spherical coordinate system, so that the bit error rate rise caused by relatively large influence of a channel on transmission is avoided.

The invention discloses a spatial distributed observation method based on irregular region geometric feature sampling, and belongs to the technical field of aerospace. The implementation method comprises the following steps: establishing a coordinate system for describing the motion of the spacecraft; establishing a spacecraft dynamic model under the coordinate system; six initial orbit elements of a satellite can be obtained based on existing low-orbit constellation orbit data, the spatial position is calculated through the orbit elements, and then position components are converted into latitude and longitude coordinates, namely sub-satellite point coordinates; defining vertex coordinates of the polygon, and constructing a planar polygon by connecting the vertex coordinates end to end; discretizing the internal region of the closed polygon; on the basis of the kinetic model, on the basis of the coordinates of the sub-satellite point and the center coordinates of the discrete sampling circle, calculating the characteristic distance from the sampling point in the observation area to the sub-satellite point, and on the basis of the size relationship between the characteristic distance and the radius of the observation view field, judging whether the irregular area can be successfully observed in a preset time constraint interval; therefore, spatial distributed observation is realized.

1. Name of the designed product: candle stand (sun, moon, stars and constellations). 2. Use of the designed product: for lighting tools. 3. Design points of the designed product: in shape. 4. Picture or photo that best shows the design points: perspective view 1.

The application discloses a four-dimensional 4nQAM constellation shaping method and system, and belongs to the technical field of constellation shaping. The method comprises the following steps: taking a coordinate origin as a square center, according to a preset constellation point priority, expanding a to-be-shaped constellation point in a concentric square from an inner layer to an outer layer in progression to obtain a two-dimensional geometric shaping constellation; mapping the two two-dimensional geometric shaping constellations to a four-dimensional space in a quadrature manner to generate a four-dimensional geometric shaping constellation; initializing and layering the four-dimensional geometric shaping constellation to obtain independent bit streams of layers of the constellation; inputting the independent bit streams into a distribution matcher of a corresponding layer to perform probability distribution matching, and obtaining a constellation symbol index sequence of the layer; layering and mapping the constellation symbol index sequence according to different Hamming weights, and performing quadrant fusion with the four-dimensional geometric shaping constellation to obtain a four-dimensional probability shaping constellation. The application not only realizes flexible construction of a 4n-order constellation, but also can adaptively adjust a constellation structure according to different application requirements.

The invention provides a method for constellation time keeping in a free operation state of a satellite-borne atomic clock, and the method comprises the steps: generating an adjustable second time frequency signal through frequency synthesis based on a first time frequency signal outputted by the satellite-borne atomic clock; comparing and measuring the phase difference between the two and sending the phase difference to an inter-satellite link; through inter-satellite measurement and interaction, obtaining a clock error between the second time frequency signals of all satellites, and converting to obtain a clock error between the first time frequency signals of all satellites; and on the basis, a clock difference parameter between the constellation time and the first time-frequency signal is calculated and converted into a clock difference parameter between the constellation time and the second time-frequency signal, a frequency adjustment parameter is generated through a control algorithm, and the second time-frequency signal is controlled to gradually approach the constellation time. The invention further provides a device for constellation time keeping in the free operation state of the satellite-borne atomic clock. Therefore, the free operation requirement and the irregular frequency modulation requirement of the satellite-borne atomic clock under the navigation constellation autonomous time keeping scene can be considered, and the constellation autonomous time keeping precision and the user service performance are improved.

The application discloses a kind of based on low-orbit giant constellation dynamic inter-satellite communication visibility calculation method, comprising the following steps: obtaining the latest TLE ephemeris data of two satellites under a certain constellation, based on TLE ephemeris data and specific epoch, the spatial position of two satellites is calculated using SGP4 orbit prediction model;Then the inter-satellite line-of-sight visibility between two satellites is calculated, and the result is characterized as a Boolean quantity;Utilize the optical power budget function based on inter-satellite laser link establishment, carry out received optical power budget;The azimuth and elevation of communication antenna under satellite body coordinate system are calculated;Finally, the visibility result of two satellites is calculated, the specific communication antenna number of satellite is determined, and the constellation inter-satellite visibility matrix is established.The application discloses a kind of based on low-orbit giant constellation dynamic inter-satellite communication visibility calculation method, constellation scale and calculation speed have higher flexibility and computing performance, inter-satellite visibility calculation is more in line with actual satellite communication scene.

A computer-implemented method is provided for acquiring a set of x unique tracking constellations in a predefined 3D space, each constellation for a corresponding wearable tracking device used to track a wearer in a 3D environment. Each unique tracking constellation includes a predefined number n tracking objects. A set of y discrete available locations is defined for locating the tracking objects within the predefined 3D space. A minimum number m of tracking objects is defined, wherein the minimum number is less than or equal to the predefined number n of tracking objects. For each unique tracking constellation, a unique discrete available location from the set of y discrete available locations is assigned to each tracking object of the tracking constellation to acquire the unique tracking constellation. The assigned location for any minimum number m of tracking objects in each unique tracking constellation is unique within the set of x unique tracking constellations.

The application relates to the technical field of satellite laser communication. The application discloses an intersatellite laser communication in-orbit calibration method, device, satellite and system, which can realize parallel initiation and cooperative execution of multi-satellite calibration tasks and improve the networking efficiency of a large-scale constellation. The method comprises the following steps: acquiring visible state information of each satellite in an intersatellite laser communication system; based on the visible state information of all satellites in the intersatellite laser communication system, performing calibration processing on all satellites in the intersatellite laser communication system in a parallel calibration mode to obtain a first final calibration result; judging whether all satellites complete calibration based on the first final calibration result to obtain a first judgment result; in the case that the first judgment result is that not all satellites complete calibration, performing calibration processing on all uncalibrated satellites in a cooperative calibration mode to obtain a second final calibration result; and the second final calibration result is used for reflecting that all satellites have completed calibration.

A space traffic management device (100) mounted in a mega-constellation business device (41) specifies one to a plurality of representative satellites from a mega-constellation satellite group flying on orbits having the same nominal orbital altitude, and has quasi-real-time high-accuracy orbital information of the representative satellite and orbital information relative values of constituent satellites other than the representative satellite, relative to the representative satellite. The space traffic management device (100) shares the quasi-real-time high-accuracy orbital information of the representative satellite and the orbital information relative values of the constituent satellites relative to the representative satellite, with the space traffic management devices (100) mounted in a plurality of business devices.

The present application relates to the field of wireless communications, is applied to an integrated sensing and communication system, and particularly relates to a communication method and apparatus, and a readable storage medium. The method comprises: a communication apparatus generates and send first information, wherein the first information is used for indicating a probability of one or more constellation points of constellation shaping, and the probability of the constellation point of constellation shaping is obtained after joint optimization of communication performance and sensing performance. The present application can simultaneously support communication and sensing, and can improve the sensing performance while taking into account the communication performance.

The application discloses a kind of multi-star on-orbit cooperation observation task planning method and system, by designing heuristic initial solution generation strategy, roulette selection algorithm based on Boltzmann selection probability, adaptive crossover operator and mutation operator based on population dispersion degree, stop condition based on population convergence coefficient, from initial solution, selection operator, crossover operator, mutation operator, stop condition etc. Various angles improve the genetic algorithm for multi-star cooperative observation task planning, compared with the genetic algorithm based on circle next cross, variation, significantly improve the execution benefit of observation task and the observation number of target point, construct the scheduling system of constellation cloud computing system, reach the purpose of on-orbit cooperation multi-star efficient execution observation task.

The invention provides a communication method and device between low-orbit constellations, and belongs to the technical field of universe navigation. According to the method, the stability of communication between the first target constellation and the second target constellation is ensured by alternately executing the first link switching strategy used for establishing the communication link with the longest communication link duration time and the second link switching strategy used for establishing the communication link with the least communication link switching times; therefore, stable communication among different LEO constellations can be realized, and the information resource integration efficiency of the low-orbit satellite internet is improved.