Satellite-ground laser communication link availability prediction method, device and system

Abstract

The invention discloses a satellite-ground laser communication link availability prediction method, device and system, and relates to the technical field of communication. The method comprises the following steps: acquiring real-time cloud picture data over a ground optical station through image acquisition equipment; based on the real-time cloud picture data, predicting cloud amount change in a satellite-ground link establishment time period, and obtaining a cloud amount distribution prediction result; on the basis of the satellite orbit related data of the target satellite and the physical position of the ground optical station, calculating to obtain a satellite transit trajectory in the satellite-to-ground link establishment time period; based on the cloud cover distribution prediction result and the satellite transit trajectory, calculating to obtain an availability result of the satellite-ground laser communication link; the availability result is used for generating a satellite-ground laser communication link control decision and a resource scheduling and topological optimization decision of the satellite-ground fusion network. The satellite-to-ground transmission efficiency, the link availability and the overall communication reliability of the satellite-to-ground convergence network can be remarkably improved.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a method, apparatus and system for predicting the availability of satellite-to-ground laser communication links. Background Technology

[0002] With the rapid development of satellite internet, laser communication has become a core technology for space networking, used to achieve high-speed interconnection between satellites and between satellites and the ground.

[0003] Currently, the satellite-to-ground laser communication link scheme involves establishing a laser communication link between the ground optical station and the satellite once the satellite enters the operational range of the ground optical station. The laser communication link is disconnected when the satellite moves beyond the operating range of the ground optical station, or when disturbances such as clouds, fog, or atmospheric turbulence occur.

[0004] Among the aforementioned interference factors, the impact of atmospheric turbulence has been effectively mitigated through existing research such as wavefront compensation techniques and optimization algorithms. However, cloud and fog interference still directly leads to laser communication link interruptions, becoming a key issue restricting the stability of satellite-to-ground communication. Currently, the main solution to cloud and fog interference is to use satellite cloud imagery and weather forecasts to predict cloud and fog conditions in the communication airspace in advance, thereby determining whether to conduct satellite-to-ground tests or service transmissions. However, this solution has significant drawbacks: firstly, long-term predictions from satellite cloud images deviate from actual on-site conditions, making accurate weather forecasting difficult and potentially causing pre-planned satellite-to-ground tests to be unable to proceed normally due to sudden weather changes. Secondly, satellite cloud images cover a wide area and cannot simulate short-term changes in cloud cover, thus failing to accurately determine the availability of the laser communication link within the link-establishable range, significantly reducing the efficiency and reliability of satellite-to-ground transmission. Summary of the Invention

[0005] In view of this, this application provides a method, apparatus, and system for predicting the availability of satellite-to-ground laser communication links. It aims to address the technical problems of existing satellite-to-ground laser communication forecasting schemes based on satellite cloud images, which suffer from deviations between long-term prediction results and actual field conditions, and the inability to simulate short-term cloud cover changes, leading to low satellite-to-ground transmission efficiency and insufficient communication reliability.

[0006] Firstly, this application provides a method for predicting the availability of a satellite-to-ground laser communication link, including: Real-time cloud image data above the ground optical station is acquired using image acquisition equipment.

[0007] Based on real-time cloud map data, cloud cover changes are predicted during the period when satellite-to-ground link establishment is possible, and cloud cover distribution prediction results are obtained.

[0008] The satellite transit trajectory during the period when a satellite-to-ground link can be established is calculated based on the satellite orbit data of the target satellite and the physical location of the ground optical station.

[0009] Based on cloud cover distribution prediction results and satellite transit trajectories, the availability of the satellite-to-ground laser communication link is calculated; the availability results are used to generate control decisions for the satellite-to-ground laser communication link and resource scheduling and topology optimization decisions for the satellite-to-ground fusion network.

[0010] Secondly, this application provides a satellite-to-ground laser communication link availability prediction device, comprising: The cloud acquisition module is configured to acquire real-time cloud image data over the ground optical station through image acquisition equipment.

[0011] The cloud cover prediction module is configured to predict cloud cover changes during the period when satellite-to-ground link establishment is possible based on real-time cloud map data, and obtain cloud cover distribution prediction results.

[0012] The orbit calculation module is configured to calculate the satellite transit trajectory during the period when a satellite-to-ground link can be established, based on the satellite orbit-related data of the target satellite and the physical location of the ground optical station.

[0013] The availability forecast module is configured to calculate the availability of the satellite-to-ground laser communication link based on cloud cover distribution prediction results and satellite transit trajectories. The availability results are used to generate control decisions for the satellite-to-ground laser communication link and resource scheduling and topology optimization decisions for the satellite-to-ground fusion network.

[0014] Thirdly, this application provides a satellite-to-ground laser communication link availability prediction system, comprising at least the satellite-to-ground laser communication link availability prediction device described in the second aspect, a ground optical station control system, a network management center, and a ground optical station; wherein... The satellite-to-ground laser communication link availability prediction device performs the satellite-to-ground laser communication link availability prediction method as described in the first aspect.

[0015] The ground optical station control system is configured to receive availability results sent by the satellite-to-ground laser communication link availability prediction device and generate satellite-to-ground laser communication link control decisions based on the availability results.

[0016] The network control center is configured to receive availability results sent by the satellite-to-ground laser communication link availability prediction device, and to make resource scheduling and topology optimization decisions for the satellite-to-ground integrated network based on the availability results.

[0017] The ground optical station is configured to receive satellite-to-ground laser communication link control decisions from the ground optical station control system and execute link control-related operations based on these decisions.

[0018] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method of the first aspect.

[0019] Fifthly, this application provides an electronic device, including a storage medium, a processor, and a computer program stored on the storage medium and executable on the processor, wherein the processor executes the computer program to implement the method of the first aspect.

[0020] In view of the embodiments described above, this application provides a method, apparatus, and system for predicting the availability of a satellite-to-ground laser communication link. It addresses the technical problems of existing satellite-to-ground laser communication forecasting schemes based on satellite cloud images, which suffer from deviations between long-term predictions and actual field conditions, and the inability to simulate short-term cloud cover changes, leading to low satellite-to-ground transmission efficiency and insufficient communication reliability. This application acquires real-time cloud image data above a ground optical station using an image acquisition device, and predicts cloud cover changes during the period when a satellite-to-ground link can be established based on this real-time cloud image data. Next, based on the target satellite's orbital data and the physical location of the ground optical station, the satellite's transit trajectory during the link-establishment period is calculated. Finally, through the superposition analysis of cloud cover changes and the satellite's transit trajectory during the link-establishment period, accurate prediction of the availability of the satellite-to-ground laser communication link is achieved.

[0021] Because image acquisition equipment features real-time on-site acquisition, it effectively avoids the inherent defects of large long-term prediction deviations in existing solutions, providing accurate on-site data support for cloud cover prediction. Predicting cloud cover changes during the period when satellite-to-ground links can be established based on real-time cloud image data effectively solves the problem of existing solutions being unable to adapt to short-term dynamic changes in cloud cover. Furthermore, by combining this with satellite transit trajectories, accurate prediction of satellite-to-ground laser communication link availability can be achieved. Based on this accurate prediction of satellite-to-ground laser communication link availability, this application can provide a scientific basis for control operations such as acquisition and tracking, link interruption and recovery at ground optical stations, and provide accurate data support for resource scheduling and topology optimization decisions in satellite-to-ground integrated networks. This significantly reduces sudden communication interruptions and data loss caused by cloud and fog interference, and significantly improves satellite-to-ground transmission efficiency, link availability, and the overall communication reliability of satellite-to-ground integrated networks.

[0022] It should be noted that the above content is only a general overview of the technical solution of this application. In order to enable those skilled in the art to clearly understand the core technical means of this application and to accurately implement this solution based on the content disclosed in the specification, the technical details of this application will be described in detail below in conjunction with specific embodiments. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this application and, together with the specification, serve to explain the principles of this application.

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 A flowchart of a satellite-to-ground laser communication link availability prediction method provided in an embodiment of this application is shown; Figure 2 A flowchart of a satellite-to-ground laser communication link availability prediction method provided in an embodiment of this application is shown; Figure 3 This illustration shows a schematic diagram of the superposition of satellite transit trajectory and cloud cover distribution in a celestial coordinate system according to an embodiment of this application. Figure 4 A flowchart of a satellite-to-ground laser communication link availability prediction method provided in an embodiment of this application is shown; Figure 5 A flowchart of a satellite-to-ground laser communication link availability prediction method provided in an embodiment of this application is shown; Figure 6 A schematic diagram of the structure of a satellite-to-ground laser communication link availability prediction device provided in an embodiment of this application is shown.

[0026] Figure 7 This paper shows a schematic diagram of the structure of a satellite-to-ground laser communication link availability prediction system provided in an embodiment of this application; Figure 8 This paper illustrates an example hardware structure of a satellite-to-ground laser communication link availability prediction device according to an embodiment of this application. Figure 9 A flowchart illustrating an implementation of satellite-to-ground laser communication link control according to an embodiment of this application is shown. Detailed Implementation

[0027] The following is combined Figure 1 The flowchart shown illustrates the execution process of a satellite-to-ground laser communication link availability prediction method. This method includes the following steps S101-S104: S101. Acquire real-time cloud image data through image acquisition equipment.

[0028] The image acquisition equipment is a meteorological observation device (such as a ground-based all-sky imager or wide-angle camera) with a wide viewing angle of 180° to 220°. It is deployed in an unobstructed area around the ground optical station, such as by pole mounting to ensure the integrity of the observation field. The core configuration of this image acquisition equipment includes a hemispherical or fisheye lens, an image acquisition unit, and a built-in image processing module. The hemispherical or fisheye lens can capture visible light images of the entire sky above the ground optical station without blind spots. The image acquisition unit transmits the continuously captured visible light image sequence to the image processing module. The image processing module uses algorithms such as image segmentation and feature extraction to identify cloud areas and clear-sky areas from the visible light images, and extracts key meteorological parameters such as cloud cover, cloud type, cloud trajectory, transmittance, and sunshine duration, ultimately integrating them to form real-time cloud image data reflecting the real-time cloud conditions on site.

[0029] For example, during a pre-set preparation phase before the target satellite enters the link-establishable range of the ground optical station, the image acquisition device (referred to as the imager) is triggered to acquire real-time cloud image data. For instance, if the time when the target satellite enters the link-establishable range of the ground optical station is set as T0, then the pre-set preparation phase is a pre-set duration before T0 (such as 5 minutes). When this pre-set preparation phase is reached (the time corresponding to 5 minutes before T0), the imager is triggered to acquire real-time cloud image data.

[0030] After the imager is activated, it captures real-time images of the sky region above the optical station from a 180° to 220° field of view using its configured fisheye lens or hemispherical mirror, generating a continuous sequence of visible light images. The built-in image processing module then performs noise reduction and enhancement preprocessing on the images. After image preprocessing, a cloud segmentation algorithm is used to distinguish cloud areas from clear-sky areas in the visible light images. Cloud cover is calculated based on pixel ratio statistics, and cloud movement trajectories are tracked using a feature matching algorithm. Simultaneously, key meteorological parameters such as transmittance and sunshine duration are calculated. Finally, the image data and the extracted key meteorological parameters are integrated to form real-time cloud image data containing both image information and key meteorological parameter information.

[0031] S102. Based on real-time cloud map data, predict the cloud cover changes during the period when satellite-to-ground link can be established, and obtain the cloud cover distribution prediction results.

[0032] The satellite-to-ground link establishment period is the time interval from the start time when the target satellite enters the physical link establishment range of the ground optical station to the interruption time when the target satellite goes out of the physical link establishment range.

[0033] For example, if the target satellite enters the physical link establishment range of the ground optical station at 10:15:00 (T0) (elevation angle ≥10°, communication distance ≤1500km) and leaves the range at 10:28:10 (T1), then [T0, T1] (a total of 13 minutes and 10 seconds) is the period during which the satellite-to-ground link can be established. At the time corresponding to 5 minutes before T0 (i.e., 10:10:00), real-time cloud image data is acquired through an imager. After obtaining the real-time cloud image data, the movement, diffusion, or dissipation trend of cloud clusters within the [T0, T1] period, as well as the specific location and percentage changes of the cloud-covered area, are simulated and predicted based on this data. Finally, the predicted cloud cover distribution results, showing the changes in cloud cover over the ground optical station at each moment within the satellite-to-ground link establishment period, are output, providing data support for subsequent link availability prediction.

[0034] S103. The satellite transit trajectory during the period when a satellite-to-ground link can be established is calculated based on the satellite orbital data of the target satellite and the physical location of the ground optical station.

[0035] The target satellite's orbital data includes the number of two rows of satellite roots and its real-time location information. The physical location of the ground optical station includes geographic coordinate data such as latitude, longitude, and altitude.

[0036] For example, firstly, by combining satellite orbital data (based on the two-line root count of the satellite, supplemented by real-time position information when necessary), the satellite's spatial position and motion state within the satellite-to-ground link-establishment period [T0, T1] are predicted. Next, based on the geographical coordinates of the ground optical station (latitude, longitude, altitude, etc.), the pointing relationship between the optical ground station and the satellite is calculated and converted into a corresponding pointing angle sequence. Finally, the satellite trajectory data corresponding to this pointing angle sequence is uniformly adapted with the coordinate system of the cloud cover distribution prediction results to obtain the satellite transit trajectory characterizing the satellite's flight path over the optical ground station during the satellite-to-ground link-establishment period.

[0037] S104. Based on the cloud cover distribution prediction results and the satellite transit trajectory, the availability of the satellite-to-ground laser communication link is calculated.

[0038] The availability results are used to generate decisions for satellite-to-ground laser communication link control and resource scheduling and topology optimization in the satellite-to-ground integrated network. For example, the availability results include the availability status identifier, available duration percentage, and unavailability reasons (e.g., cloud cover) for each stage (moment) within the link-establishment period. Based on these availability results, accurate data can be provided for satellite-to-ground laser communication link control decisions (such as selecting the timing for acquisition and tracking initiation, and planning link interruption and recovery procedures). Simultaneously, data support can be provided for resource scheduling and topology optimization decisions in the satellite-to-ground integrated network (such as adjusting service flow distribution priorities and dynamically updating the network's link topology), helping to improve the stability of satellite-to-ground communication and the overall network transmission efficiency.

[0039] For example, the satellite's transit trajectory is overlaid with the predicted cloud map data corresponding to the cloud cover distribution prediction results to determine the spatial location of the line-of-sight link in the predicted cloud map data. Next, the overlap range and obstruction degree between the line-of-sight link and the cloud-covered area are analyzed to determine whether the laser communication transmission conditions are met at each stage within the satellite-to-ground link establishment period, and based on the determination results, availability results at the corresponding granularity are generated.

[0040] The granularity of the availability results can be at the second, millisecond, or minute level, and can be flexibly adjusted according to the service requirements of satellite-to-ground laser communication (such as real-time performance and transmission capacity) and the system computing power configuration.

[0041] For example, if the target satellite is a low-Earth orbit satellite (with a fast transit speed and a short link establishment window, such as 10-15 minutes), and carries high-precision real-time services such as emergency communications, availability results need to be generated at the second level. For instance, the satellite-to-ground link establishment period [T0, T1] is divided into time slices in units of 1 second. Using a coordinate unification algorithm, the satellite transit trajectory in the celestial coordinate system (including the right ascension and declination coordinates corresponding to each second) is superimposed with the cloud cover distribution prediction results (the cloud coverage pixel matrix corresponding to each second) to accurately locate the pixel range of the line-of-sight link in the predicted sky cloud map per second. Then, through pixel ratio statistics and cloud density analysis, the overlap ratio (e.g., 5%, 35%) and occlusion level (no occlusion, partial occlusion, complete occlusion) between the line-of-sight link and the cloud coverage area within each second are determined. If the overlap ratio is ≤15% and the occlusion level is no occlusion / slight occlusion and the light transmittance is ≥80%, then the laser communication transmission conditions are met for that second and it is marked as "available". Otherwise, it is marked as "unavailable". Finally, a second-level availability result is generated, which includes the availability status per second, the continuous available period, and the reason for unavailability.

[0042] If the target satellite is a medium-to-high orbit satellite (with slow transit speed and long link establishment window, such as 30-60 minutes), and carries non-real-time high-capacity data transmission services (such as remote sensing image backhaul), availability results can be generated at the minute level. For example, the time period during which a satellite-to-ground link can be established can be divided into time slices of 1 minute each. The average path of the satellite's transit trajectory and the average state of cloud cover distribution prediction within that minute are superimposed. The overall overlap ratio and obstruction situation of the line-of-sight link within that minute are analyzed. If the overlap ratio is ≤20% and the cumulative available time is ≥40 seconds, then the minute is determined to meet the transmission conditions and is marked as "available". A minute-level availability result containing the available status and available time percentage for each minute is generated, reducing system computing power consumption while ensuring transmission requirements.

[0043] If the satellite-to-ground communication system has sufficient computing power and needs to cope with sudden changes in cloud cover and fog within a very short time (such as instantaneous obstruction caused by severe convective weather), millisecond-level granularity can be adopted. For example, by setting the time slice to 100 milliseconds, high-speed data processing algorithms can be used to perform millisecond-level overlay analysis of satellite trajectory and cloud image data, generating millisecond-level availability results. This provides ground optical stations with more precise link control timing (such as triggering link interruption 500 milliseconds in advance), further reducing the risk of data loss.

[0044] The availability prediction method for satellite-to-ground laser communication links provided in the embodiments of this application will be described in detail below.

[0045] This application also provides an implementation method for predicting cloud cover changes during the satellite-to-ground link-establishment period based on real-time cloud image data, thereby obtaining cloud cover distribution prediction results. The implementation method includes: based on real-time cloud image data, using a preset extrapolation algorithm to dynamically simulate and predict the changes in the movement vector, coverage area, and distribution pattern of cloud clusters during the satellite-to-ground link-establishment period, thereby obtaining cloud cover distribution prediction results.

[0046] For example, the preset extrapolation algorithm includes optical flow extrapolation algorithm, spatiotemporal sequence model, etc.

[0047] Taking optical flow extrapolation as the preset extrapolation algorithm as an example, the visible light image in the real-time cloud image data is first preprocessed to improve the distinction between cloud areas and clear sky areas through noise reduction and image enhancement techniques. Then, optical flow calculation methods such as Lucas-Kanade are used to extract the motion vectors (including movement direction and velocity) of key cloud feature points in the cloud image. Finally, based on these motion vectors, the displacement, diffusion, or dissipation process of cloud clusters during the satellite-to-ground link-establishment period is linearly extrapolated to simulate the coverage area and distribution pattern of cloud clusters at each time point, generating cloud cover distribution prediction results.

[0048] Taking a pre-defined extrapolation algorithm as an example of a spatiotemporal sequence model, this model includes a convolutional layer (Conv), a Long Short-Term Memory (LSTM) network structure, and a Recurrent Convolutional Network (RCN) structure. Using continuously acquired multi-frame real-time cloud image data as input, the spatial features of the cloud clusters (such as shape contours, density distribution, and edge details) are first extracted through the convolutional layer (Conv). Then, the LSTM structure is used to mine the temporal dependencies of cloud cluster movement, capturing the temporal variation patterns between different frames of cloud images. Simultaneously, the RCN is used to enhance the fitting ability of the dynamic changes of the cloud clusters, adapting to complex scenarios such as cloud diffusion and dissipation. Through the collaborative computation of the three-layer network structure, nonlinear predictions are made on the movement trend and coverage changes of the cloud clusters within the chainable time period, outputting the cloud cover distribution prediction results.

[0049] This application also provides an implementation method for calculating the satellite transit trajectory during the satellite-to-ground link-establishable period based on satellite orbital data of the target satellite and the physical location of the ground optical station. For example... Figure 2 As shown, this implementation includes the following steps S201 to S204: S201. Using the two rows of satellite roots of the target satellite as input, the orbital mechanics algorithm is used to predict the spatial position and motion status data of the target satellite during the period when a satellite-to-ground link can be established.

[0050] For example, the HPOP orbital mechanics algorithm is used, combined with correction parameters such as the Earth's gravitational field model and atmospheric drag model, to simulate the satellite's trajectory during the satellite-to-ground link-establishment period [T0, T1], and output the target satellite's three-dimensional spatial coordinates, flight speed, attitude angle, and other motion state data.

[0051] S202. Based on the physical location of the ground optical station and the spatial location and motion state data of the target satellite, calculate the pointing vector required for the ground optical station to align with the target satellite.

[0052] For example, physical location data such as latitude, longitude, and altitude are extracted from the ground optical station (or calibrated in real time by the positioning system). This physical location data is converted into three-dimensional Cartesian coordinates (X0, Y0, Z0). This is then combined with the real-time satellite spatial coordinates (X0, Y0, Z0) output by S201. S ,Y S Z S The pointing vector (X) is calculated using the spatial vector operation formula. S -X0,Y S -Y0,Z S -Z0), this pointing vector represents the spatial direction in which the ground optical station points towards the target satellite.

[0053] S203. Convert the pointing vector into a pointing angle sequence of the ground optical station during the satellite-to-ground link establishment period, and extract the satellite trajectory data corresponding to the pointing angle sequence.

[0054] For example, based on the transformation relationship between the spherical coordinate system and the spatial rectangular coordinate system, the pointing vector obtained by S202 is decomposed into azimuth (AZ) and elevation (EL). Among them, the azimuth is the angle between the projection of the pointing vector on the horizontal plane and the due north direction, and the elevation is the angle between the pointing vector and the horizontal plane.

[0055] Next, based on the time series within the period when a link can be established between the satellite and the ground, a continuous sequence of pointing angles (AZ1, EL1), (AZ2, EL2)...(AZ1, EL1) is generated. n ,EL n And simultaneously extract the satellite trajectory data corresponding to the pointing angle sequence to form a satellite trajectory dataset.

[0056] S204. Convert the satellite trajectory data into a coordinate system consistent with the cloud cover distribution prediction results to obtain the satellite transit trajectory.

[0057] For example, if the cloud cover distribution prediction results are output in celestial coordinates, the satellite trajectory data (three-dimensional rectangular coordinates) extracted by S203 is converted into right ascension and declination coordinates in celestial coordinates using a coordinate transformation algorithm. During the transformation process, correction factors such as Earth's rotation angle, nutation, and precession are introduced to ensure that the spatial reference of the satellite trajectory data is consistent with that of the cloud image data, thus obtaining the continuous flight path of the satellite within the linkable period in celestial coordinates, i.e., the satellite transit trajectory.

[0058] like Figure 3 The diagram illustrates the overlay of satellite transit trajectories and cloud cover distribution in a celestial coordinate system. The observation point at the ground-based optical station is taken as the center of the celestial sphere, the basic circle as the celestial equator, and the North Celestial Pole pointing towards the polar axis. Satellite positions are determined by right ascension (measured eastward along the celestial equator) and declination (measured north / south of the celestial equator), achieving complete spatial consistency with the cloud cover distribution prediction results (with correction factors for Earth's rotation angle, nutation, and precession already incorporated).

[0059] Figure 3 Regions 1 through 4 are cloud-covered areas in the celestial coordinate system. During the time periods T0 to t1 and t2 to T1, the satellite's transit trajectory did not overlap with any cloud-covered areas, and the cloud cover prediction module verified that the cloud thickness during these periods was ≤500 meters (transmittance ≥85%), meeting the energy attenuation requirements for laser communication transmission (attenuation ≤3dB), thus classifying these periods as "usable." The ground optical station can initiate acquisition and tracking in standard mode, using the default laser emission power (e.g., 10W) ​​and transmission rate (e.g., 10Gbps), requiring no additional anti-interference configuration.

[0060] During the period from t1 to t2, the satellite's transit trajectory falls entirely within the cloud coverage area of ​​Region 1, and the measured / predicted cloud thickness in Region 1 is ≥1500 meters (transmittance ≤30%). The energy attenuation of the laser signal after absorption and scattering by the cloud layer is ≥20dB, far exceeding the tolerance threshold of the communication link (usually ≤10dB). The line-of-sight link is completely blocked, which is determined to be an "unusable period". The link interruption and data caching process needs to be initiated in advance.

[0061] In some implementations, the current position information of the target satellite is obtained in real time through the BeiDou short message transceiver module; using the satellite's two-line root number and current position information as input, the orbital mechanics algorithm is used to predict the spatial position and motion status data of the target satellite during the period when a satellite-to-ground link can be established.

[0062] The BeiDou short message transceiver module is a communication module deployed based on the short message communication function of the BeiDou satellite navigation system. Its core function is to provide near real-time measured position data support for orbit prediction in satellite-to-ground communication scenarios. It complements the satellite's two-line root data, and by combining measured data with theoretical orbit data, it improves the prediction accuracy of orbit mechanics algorithms for the target satellite's spatial position and motion state.

[0063] For example, firstly, the satellite's two-row root numbers are obtained and input into the orbital mechanics algorithm model as the theoretical orbital basis data. This allows for a preliminary estimation of the satellite's spatial position and motion state changes within the satellite-to-ground link-establishment period [T0, T1]. Simultaneously, the target satellite's current position data is captured in real-time via the BeiDou short message transceiver module. This measured data is compared with the satellite position data initially estimated by the algorithm for the same period, and the deviation is calculated. Based on this deviation, the orbital mechanics algorithm's estimation parameters are dynamically corrected. The corrected algorithm model then accurately predicts the satellite's spatial position and motion state data within the satellite-to-ground link-establishment period, outputting the target satellite's spatial position and motion state data for that period.

[0064] This application also provides an implementation method for calculating the availability of a satellite-to-ground laser communication link based on cloud cover distribution prediction results and satellite transit trajectories, such as... Figure 4 As shown, this embodiment includes the following steps S301 to S303: S301. Overlay the satellite transit trajectory with the predicted cloud map data corresponding to the cloud cover distribution prediction results to obtain the spatial location of the line-of-sight link corresponding to the satellite transit trajectory in the predicted cloud map data.

[0065] For example, firstly, a coordinate unification algorithm is used to align the satellite transit trajectory (including right ascension and declination time-series data) in the celestial coordinate system with the predicted cloud map data (in the same celestial coordinate system) corresponding to the cloud cover distribution prediction results, using a spatial reference. Then, based on graphic overlay technology, the continuous path vector of the satellite transit trajectory is matched point-by-point with the pixel matrix of the predicted cloud map data to determine the pixel coordinate range of the line-of-sight link (the straight communication path between the ground optical station and the satellite) at each moment in the predicted cloud map data, thereby locating its spatial position.

[0066] S302. Based on the spatial location of the line-of-sight link corresponding to the satellite transit trajectory in the predicted cloud image data, determine the overlap analysis results.

[0067] The overlap analysis results characterize the degree of overlap and occlusion between the line-of-sight link corresponding to the satellite's transit trajectory and the cloud-covered area in the predicted cloud image data during the satellite-to-ground link establishment period. For example, the percentage of pixels covered by clouds in the pixel region corresponding to the line-of-sight link (overlap degree, such as 30% overlap, 100% overlap) is calculated using a pixel percentage statistical method. Based on the cloud density parameters of the overlapping pixels (provided by the cloud cover distribution prediction results) and occlusion level classification rules, the occlusion level (such as no occlusion, partial occlusion, complete occlusion) is determined, ultimately forming an overlap analysis result that includes the overlap percentage and occlusion level at each time point.

[0068] S303. Based on the overlap analysis results, determine whether the target satellite and the ground optical station meet the laser communication transmission conditions during the satellite-to-ground link establishment period, and generate availability results.

[0069] The laser communication transmission conditions include, for example, the overlap ratio between the link and the cloud coverage area is ≤ a preset threshold (e.g., 15%) and the occlusion level is “no occlusion” or “slight occlusion” (cloud density ≤ 0.3), while also meeting the minimum transmittance requirement for laser transmission (e.g., transmittance ≥ 80%).

[0070] For example, if the overlap analysis result at a certain moment is "overlap ratio 8%, obstruction level no obstruction, transmittance 85%", then it is determined that the laser communication transmission conditions are met, and the link at that moment is marked as "available". If the overlap ratio at a certain moment is 25%, the obstruction level is partial obstruction, and the transmittance is 72%, then it is determined that the transmission conditions are not met, and the link at that moment is marked as "unavailable". Finally, the judgment results of all moments within the satellite-to-ground link establishment period are integrated to generate an availability result that includes available time period intervals, unavailable time period intervals, the proportion of each interval, and the reasons for unavailability (such as partial or complete obstruction by clouds and fog).

[0071] Furthermore, after obtaining the spatial location of the line-of-sight link corresponding to the satellite transit trajectory in the predicted cloud image data, this application also provides an embodiment for generating availability results at the time slice granularity, such as... Figure 5 As shown, this embodiment includes the following steps S401 to S403: S401. Divide the time period during which a satellite-to-ground link can be established into multiple consecutive time slices.

[0072] For example, time slices can be set to preset time intervals. For instance, 1 second can be used as the unit (to adapt to second-level planning requirements), or it can be adjusted to 0.5 seconds or 2 seconds according to actual communication accuracy requirements. If the satellite-to-ground link establishment period is [T0, T1] (e.g., 10:15:00-10:28:10), then it is divided into 800 consecutive time slices at 1-second intervals (t0=10:15:00, t1=10:15:01, ..., t799=10:28:10), and each time slice corresponds to a unique timestamp identifier.

[0073] S402. Determine the degree of overlap and occlusion between the line-of-sight link corresponding to the satellite transit trajectory and the cloud-covered area in the predicted cloud image data within each time slice, and obtain the overlap analysis results corresponding to each time slice.

[0074] For example, for each time slice ti (i=0 to n, where n is the total number of time slices), the pixel region of the line-of-sight link of the satellite transit trajectory corresponding to that time slice, as well as the pixel data of the cloud-covered area in the cloud cover distribution prediction results of the same period, are extracted. The overlapping pixel ratio is calculated by comparing pixels one by one (e.g., when ti=10:15:03, the overlapping ratio is 6%), and the occlusion level is determined by combining the cloud density parameter (e.g., no occlusion), forming an independent overlap analysis result for each time slice.

[0075] S403. Based on the overlap analysis results corresponding to each time slice, determine whether the target satellite and the ground optical station meet the laser communication transmission conditions within each time slice, and generate availability results at the time slice level.

[0076] For example, for each time slice ti, a determination is made one by one based on the aforementioned laser communication transmission conditions. If the overlap ratio corresponding to ti is ≤15%, the occlusion level is no occlusion / slight occlusion, and the transmittance is ≥80%, then the slice is marked as "available" (identified as 1). Otherwise, it is marked as "unavailable" (identified as 0). Finally, an availability result table is generated with time slices as the smallest unit, including key parameters such as timestamp, availability status identifier, overlap ratio, occlusion level, and transmittance. At the same time, statistical information such as the total number of available time slices, their percentage, and continuous available time periods are output, providing second-level accurate data support for link control decisions.

[0077] After obtaining the availability results of the satellite-to-ground laser communication link, this application can use the availability results to guide the generation of control decisions for the satellite-to-ground laser communication link, as well as resource scheduling and topology optimization decisions for the satellite-to-ground fusion network.

[0078] In some embodiments, availability results are sent to the ground optical station control system; the availability results are used to guide the ground optical station control system to generate satellite-to-ground laser communication link control decisions, and the satellite-to-ground laser communication link control decisions are used to control the ground optical station to perform link control related operations.

[0079] Among them, the control decisions for satellite-to-ground laser communication links include decisions on link establishment timing, acquisition and tracking parameter configuration, link maintenance strategy, early link termination, link reconstruction triggering, and communication mode switching.

[0080] For example, availability results may include core information such as the availability status (available / unavailable) of each time slice within the satellite-to-ground link-establishment period [T0, T1], the start / end timestamps of consecutive available periods, the occlusion level and estimated recovery time of unavailable periods, and the transmittance threshold. After receiving this availability result information, the ground optical station control system, combining the ground optical station's hardware performance parameters (such as laser emission power adjustment range and acquisition / tracking response speed) with a pre-set link control rule base, generates refined control decisions adapted to different link states. For continuous available time periods (e.g., time slice t0-t80, corresponding to 0-80 seconds, with an availability status marked as "available," transmittance ≥88%, and no obstruction), decisions are made regarding link establishment timing and acquisition / tracking parameter configuration. For example, the acquisition / tracking system is warmed up 2 seconds before t0, the antenna pointing accuracy is preset to ±0.1°, the laser emission unit is triggered at t0 to perform satellite alignment and link establishment operations, the standard communication mode is used to maintain link stability, and the tracking bandwidth is set to 50Hz to adapt to the satellite's motion trajectory.

[0081] For available periods with slight occlusion (e.g., time slice t200-t260, corresponding to 200-260 seconds, with an availability status of "available," transmittance of 70%-80%, and occlusion level of "slight occlusion"), communication mode switching decisions and link maintenance strategy decisions are generated. For example, an anti-occlusion coded modulation mode (e.g., LDPC encoding) is enabled, increasing the laser emission power by 20% while reducing the data transmission rate to 75% of the original rate, maintaining the normal operation of the acquisition and tracking system, and offsetting the signal attenuation caused by occlusion by dynamically adjusting the tracking gain.

[0082] For unavailable periods of complete blockage (such as time slice t350-t420, corresponding to seconds 350-420, with an availability status of "unavailable," a blockage level of "complete blockage," and an estimated recovery time of t421), a link early interruption decision is generated. For example, a data caching mechanism is activated at time t345 to save the current communication session state and untransmitted data fragments, and the laser emitting unit is shut down in advance at time t348, adjusting the optical antenna to a low-power standby pose to avoid equipment wastage and invalid tracking.

[0083] For the recovery phase following the end of the unavailable period (e.g., estimated recovery time t421, corresponding to time slice t421-t500, where the availability status changes from "unavailable" to "available" and transmittance recovers to 85%), a link reconstruction trigger decision is generated. For example, at time t420, the link reconstruction preparation process is initiated, the acquisition and tracking system is woken up and historical alignment parameters are loaded, and at time t421, the antenna is triggered to quickly point to the target satellite trajectory, the link reconstruction operation is performed, and the data transmission session is simultaneously restored.

[0084] For available periods with intermittent obstruction (e.g., time slice t600-t650, corresponding to 600-650 seconds, with availability status indicators alternating between "available" and "unavailable," and obstruction level of "intermittent slight obstruction"), link maintenance strategy decisions and dynamic adjustment decisions for acquisition and tracking parameters are generated. For example, while maintaining the communication mode, the anti-interference threshold of the acquisition and tracking system is increased by 30%, the tracking bandwidth is dynamically adjusted to switch between 30Hz and 60Hz, and real-time signal quality monitoring is initiated. When the signal-to-noise ratio falls below a preset threshold (e.g., 10dB), a temporary data retransmission mechanism is activated to ensure communication continuity.

[0085] The above-mentioned satellite-to-ground laser communication link control decision-making can achieve precise link management, ensure communication stability, and reduce equipment wear and tear.

[0086] In some embodiments, availability results are reported to the network management center; the availability results are used to guide the network management center in making resource scheduling and topology optimization decisions for the satellite-ground integrated network.

[0087] Among them, the resource scheduling and topology optimization decisions of the space-ground converged network include: traffic diversion scheduling, dynamic allocation of transmission bandwidth, on-demand scheduling of relay nodes, dynamic adjustment of link priorities, dynamic updating of the entire network topology, optimization of routing protocol parameters, planning of network redundant paths, and temporary shielding of low-availability links.

[0088] For example, availability results may include core information such as the availability status identifier, availability duration percentage, link quality score (e.g., predicted signal attenuation, estimated bit error rate), distribution of unavailable periods, and obstruction level for each time slice within the satellite-to-ground link establishment period [T0, T1]. After receiving this availability result, the network management center, in conjunction with the current network-wide service load, service priority levels (e.g., emergency communication is level one, normal data transmission is level two), and the real-time status of each satellite-to-ground link and inter-satellite link, performs refined resource scheduling and topology optimization operations. In the business flow diversion and scheduling, if the available time of a certain satellite-to-ground link (such as link A) is only 38%, and it carries the emergency command data transmission requirements of the first priority, the network control center will analyze the status of other satellite-to-ground links during the same period and find that the available time of link B is 91% and the current load rate is only 45%. Then, the emergency business flow of link A will be diverted to link B in advance, while the bandwidth of the available time of link A will be reserved for the transmission of non-real-time data of the second priority (such as environmental monitoring data) to ensure uninterrupted transmission of high-priority services.

[0089] Transmission bandwidth is dynamically allocated. For high-availability links (such as link C) with an availability time of 89% and a link quality score of ≥85, if there is a large-capacity remote sensing image backhaul demand across the entire network, the network management center will dynamically adjust the transmission bandwidth of this link from the default 10Gbps to 20Gbps to improve data transmission efficiency. For links with an availability time of 55% and intermittent obstruction (such as link D), the bandwidth will be maintained at 5Gbps to avoid wasting bandwidth resources.

[0090] Relay nodes are scheduled on demand. If the availability of the direct satellite-to-ground link (such as link E) between a ground optical station and the target satellite in a certain area is only 29% (due to dense cloud cover in the area), the network control center can query the inter-satellite link status and find that the low-Earth orbit relay satellite F has a high availability inter-satellite / satellite-to-ground link (availability ≥ 80%) with both the target satellite and the ground optical station. Then, relay satellite F is scheduled as a relay node to build an indirect communication path of "target satellite - relay satellite F - ground optical station" to ensure continuous service transmission.

[0091] The entire network topology is dynamically updated. Based on the availability of each satellite-to-ground link, the network control center updates the network topology map in real time. Links with availability ≥80% are marked as "preferred links" and assigned high routing weights; links with availability 30%-80% are marked as "backup links"; and links with availability <30% are marked as "temporarily unavailable links" and temporarily removed from the current active topology. Simultaneously, the updated topology information is pushed to all nodes (satellites and ground optical stations) to ensure that each node forwards data based on the latest topology status.

[0092] Routing protocol parameters were optimized. For satellite-to-ground links marked as "backup links" (such as link G), which are subject to slight obstruction during their available time, causing signal fluctuations, the network management center shortened the OSPF routing protocol Hello message sending interval for the corresponding link from 10 seconds to 3 seconds and the link failure judgment time from 40 seconds to 15 seconds. This ensures that the route can converge quickly when the link state changes abruptly, reducing data forwarding latency.

[0093] Network redundancy path planning: If a core ground optical station in a key area relies on only one satellite-to-ground link (such as link H) to communicate with the satellite, and the availability of this link accounts for 62% of the time, there is a risk of single point of failure. Based on the availability results of surrounding ground optical stations, the network control center plans a redundant path of "core ground station - surrounding ground station - satellite". When link H enters an unavailable period, it automatically switches to the redundant path to transmit data, ensuring communication continuity.

[0094] For low-availability links, if the availability of a satellite-to-ground link (such as link I) remains below 30% for three consecutive task cycles, the network management center will determine that the link does not currently have stable communication conditions and will temporarily block it, no longer assigning new business tasks to it. At the same time, a link maintenance alarm will be triggered, notifying the operation and maintenance personnel to check the regional weather conditions or equipment status. The link will be reactivated after its availability recovers to above 30%.

[0095] The resource scheduling and topology optimization decisions of the aforementioned space-ground converged network ensure continuous transmission of high-priority services, achieve efficient utilization of network resources, and enhance the stability and anti-interference capabilities of the space-ground converged network.

[0096] Furthermore, this embodiment provides a satellite-to-ground laser communication link availability prediction device 600, such as... Figure 6 As shown, the device includes a cloud cover acquisition module 610, a cloud cover prediction module 620, a track calculation module 630, and an availability forecast module 640. Among them: The cloud data acquisition module 610 is configured to acquire real-time cloud image data through an image acquisition device.

[0097] The cloud cover prediction module 620 is configured to predict cloud cover changes during the period when satellite-to-ground link establishment is possible based on real-time cloud map data, and obtain cloud cover distribution prediction results.

[0098] The orbit calculation module 630 is configured to calculate the satellite transit trajectory during the period when a satellite-to-ground link can be established based on the satellite orbit-related data of the target satellite and the physical location of the ground optical station.

[0099] The availability prediction module 640 is configured to calculate the availability results of the satellite-to-ground laser communication link based on the cloud cover distribution prediction results and the satellite transit trajectory; the availability results are used to generate control decisions for the satellite-to-ground laser communication link and resource scheduling and topology optimization decisions for the satellite-to-ground fusion network.

[0100] In some embodiments, the cloud cover prediction module 620 is further configured to dynamically simulate and predict the changes in the motion vector, coverage area, and distribution pattern of cloud clusters during the satellite-to-ground link-establishment period based on real-time cloud map data and a preset extrapolation algorithm, thereby obtaining cloud cover distribution prediction results.

[0101] In some embodiments, the orbit calculation module 630 is further configured to use the satellite two-row roots of the target satellite as input and employ orbital mechanics algorithms to predict the spatial position and motion state data of the target satellite during the period when a satellite-to-ground link can be established.

[0102] Based on the physical location of the ground optical station and the spatial location and motion data of the target satellite, the pointing vector required for the ground optical station to align with the target satellite is calculated.

[0103] The pointing vector is converted into a pointing angle sequence of the ground optical station during the satellite-to-ground link establishment period, and the satellite trajectory data corresponding to the pointing angle sequence is extracted.

[0104] The satellite trajectory data is converted into a coordinate system consistent with the cloud cover distribution prediction results to obtain the satellite transit trajectory.

[0105] In some embodiments, the orbit calculation module 630 is also configured to acquire the current position information of the target satellite in real time through the BeiDou short message transceiver module.

[0106] Using the satellite's two rows of roots and current position information as input, the orbital mechanics algorithm is used to predict the target satellite's spatial position and motion status data during the period when a satellite-to-ground link can be established.

[0107] In some embodiments, the availability prediction module 640 is further configured to overlay the satellite transit trajectory with the predicted cloud map data corresponding to the cloud cover distribution prediction result to obtain the spatial location of the line-of-sight link corresponding to the satellite transit trajectory in the predicted cloud map data.

[0108] Based on the spatial location of the line-of-sight link corresponding to the satellite transit trajectory in the predicted cloud image data, the overlap analysis results are determined. The overlap analysis results characterize the degree of overlap and occlusion between the line-of-sight link corresponding to the satellite transit trajectory and the cloud-covered area in the predicted cloud image data during the period when a satellite-to-ground link can be established.

[0109] Based on the overlap analysis results, it is determined whether the target satellite and the ground optical station meet the laser communication transmission conditions during the satellite-to-ground link establishment period, and availability results are generated.

[0110] In some embodiments, the availability forecast module 640 is further configured to divide the satellite-to-ground link-establishment period into multiple consecutive time slices.

[0111] Within each time slice, the degree of overlap and occlusion between the line-of-sight link corresponding to the satellite transit trajectory and the cloud-covered area in the predicted cloud image data is determined, and the overlap analysis results corresponding to each time slice are obtained.

[0112] Based on the overlap analysis results corresponding to each time slice, it is determined whether the target satellite and the ground optical station meet the laser communication transmission conditions within each time slice, and availability results are generated at the time slice level.

[0113] In some embodiments, the apparatus further includes an interaction and reporting module 650 configured to send availability results to a ground optical station control system; the availability results are used to guide the ground optical station control system to generate satellite-to-ground laser communication link control decisions, which are used to control the ground optical station to perform link control-related operations.

[0114] In some embodiments, the interaction and reporting module 650 is further configured to report availability results to the network management center; the availability results are used to guide the network management center in making resource scheduling and topology optimization decisions for the satellite-ground converged network.

[0115] It should be noted that other corresponding descriptions of the functional units involved in the satellite-to-ground laser communication link availability prediction device provided in this embodiment can be found in the description of the satellite-to-ground laser communication link availability prediction method in the above embodiments, and will not be repeated here.

[0116] Furthermore, this embodiment provides a satellite-to-ground laser communication link availability prediction system, such as... Figure 7 As shown, the system includes a satellite-to-ground laser communication link availability prediction device 700, a ground optical station control system 710, a network management center 720, and a ground optical station 730.

[0117] The satellite-to-ground laser communication link availability prediction device 700 performs any of the embodiments described in the satellite-to-ground laser communication link availability prediction method.

[0118] In some embodiments, the satellite-to-ground laser communication link availability prediction device 700 includes the cloud cover acquisition module 610, cloud cover prediction module 620, orbit calculation module 630, availability prediction module 640, interaction and reporting module 650, and BeiDou short message transceiver module 701, all found in the satellite-to-ground laser communication link availability prediction device 600 described above. The cloud cover acquisition module 610, cloud cover prediction module 620, orbit calculation module 630, availability prediction module 640, and interaction and reporting module 650 have already been described in the above embodiments and will not be repeated here. The BeiDou short message transceiver module 701 is an optional module in the satellite-to-ground laser communication link availability prediction device 600, achieving physical connection and data interaction with the device 600 through a standardized communication interface. In the device 700, it is directly integrated as a core functional module into the device hardware platform, forming a collaborative architecture with the existing modules such as the cloud cover acquisition module 610 and cloud cover prediction module 620.

[0119] like Figure 8As shown, the hardware structure of the satellite-to-ground laser communication link availability prediction device 700 includes a wide-angle camera (such as an imager) 810, an electronics board 820, a BeiDou short message transceiver device 830, and an external interface 840. The wide-angle camera 810 corresponds to the cloud cover acquisition module 610, which uses a 180°-220° wide-angle fisheye lens or hemispherical mirror to capture real-time visible light images of the entire area above the ground optical station 730. The built-in image processing unit extracts meteorological parameters such as cloud cover, cloud trajectory, and transmittance, generating current cloud image data and transmitting it to the electronics board 820.

[0120] Electronics board 820 is the core computing unit of device 700, integrating a high-performance processor and storage module. It houses the core algorithm logic for cloud cover prediction module 620, orbit calculation module 630, and availability prediction module 640, with the following specific functions: The system connects to the cloud cover acquisition module (wide-angle camera 810) to receive visible light images of the entire area above the ground optical station 730, as well as meteorological parameters such as cloud cover, cloud trajectory, and transmittance. Through algorithms such as optical flow extrapolation and ConvLSTM-RCN spatiotemporal sequence model, it completes dynamic simulation and prediction of cloud movement vectors, coverage range, and distribution patterns within the satellite-to-ground link-established period [T0, T1], and outputs refined cloud cover distribution prediction results.

[0121] The system receives the current position information of the target satellite transmitted by the Beidou short message transceiver device 830, combines the satellite's two-line roots with the physical position data such as latitude, longitude, and altitude of the ground optical station 730, and predicts the satellite's spatial position and motion state within [T0,T1] using orbital mechanics algorithms such as HPOP. It calculates the pointing vector of the ground station aligned with the satellite and converts it into a sequence of azimuth and elevation angles. After coordinate system adaptation, it generates the satellite's transit trajectory.

[0122] The cloud cover distribution prediction results are overlaid with the satellite transit trajectory, and the overlap and obstruction level between the line-of-sight link and the cloud coverage area are analyzed by time slice (second / millisecond level). The laser communication transmission conditions at each time period are determined to determine whether they are met. Finally, the link availability results containing core information such as availability status, availability duration percentage, and reasons for unavailability are generated, providing data support for subsequent link control decisions and network optimization.

[0123] The Beidou short message transceiver device 830 is responsible for receiving real-time measured data of the target satellite's current position and transmitting it to the electronics board 820.

[0124] The external interface 840 includes a data transmission interface (such as Ethernet, PCIe) and a control interface, which are used to realize the communication and interaction between the device 700 and the ground optical station control system 710 and the network management and control center 720, push availability results to the corresponding terminals, and receive external control commands (such as mission planning commands and parameter configuration commands) to ensure the coordinated operation of the device and external systems.

[0125] The ground optical station control system 710 is configured to receive availability results sent by the satellite-to-ground laser communication link availability prediction device and generate satellite-to-ground laser communication link control decisions based on the availability results.

[0126] Network Control Center 720 is configured to receive availability results sent by the satellite-to-ground laser communication link availability prediction device, and to perform resource scheduling and topology optimization decisions for the satellite-to-ground converged network based on the availability results.

[0127] Ground optical station 730 is configured to receive satellite-to-ground laser communication link control decisions from ground optical station control system 710 and perform link control-related operations based on the satellite-to-ground laser communication link control decisions.

[0128] In some embodiments, the above-described methods, apparatus, and systems for predicting the availability of satellite-to-ground laser communication links are combined with... Figure 7 The system structure is shown. An implementation process for satellite-to-ground laser communication link control is introduced, such as... Figure 9 As shown, the implementation process includes: (1) Space-to-ground mission planning.

[0129] The Network Control Center 720, taking into account network communication needs, cloud image forecasts, satellite orbit characteristics, and the geographical location of the ground optical station 730, comprehensively plans the needs for establishing satellite-to-ground links in the near future, formulates a mission plan, and distributes it to the satellite and the ground optical station 730.

[0130] (2) The chain establishment time is determined.

[0131] Based on the mission requirements of the network control center 720, the ground optical station 730 calculates the transit time of the target satellite and the feasibility of establishing a link, and carries out preliminary preparations for establishing a link. Finally, the start time of establishing the link is determined to be T0, and the time when the satellite actively interrupts the link after it goes out of the link establishment range is T1. The time period during which the satellite and ground can establish a link is [T0, T1].

[0132] (3) Cloud map data collection.

[0133] During the preparation period from 5 minutes before T0 to T0, the cloud acquisition module 610 captures real-time cloud image data of the airspace of the ground optical station 730 through the image acquisition device and transmits it to the cloud prediction module 620.

[0134] (4) Cloud cover distribution prediction.

[0135] The cloud cover prediction module 620 first performs threshold extraction and color feature processing on the received real-time cloud image data, and generates standardized cloud cover images using models such as U-NET. Then, based on multiple sets of cloud images, it performs feature recognition and matching to extract cloud cluster motion vectors. Using methods such as optical flow extrapolation and the ConvLSTM-RCN spatiotemporal sequence model, it dynamically simulates and extrapolates cloud cover changes within the [T0, T1] time period to obtain refined cloud cover distribution prediction results. Subsequently, the cloud cover prediction module 620 sends the cloud cover distribution prediction results to the availability forecast module 640.

[0136] (5) Calculation of satellite transit trajectory.

[0137] The orbit calculation module 630 takes the satellite two-line roots (TLE) as the basic input. If the BeiDou short message transceiver module 701 is configured, real-time satellite orbit data can be acquired simultaneously as a supplement. The orbit data is extrapolated to the [T0, T1] time interval, and the satellite's geographic coordinate system position is unified to the target coordinate system through coordinate transformation. The pointing vector of the ground optical station 730 aligned with the satellite is calculated and converted into the azimuth and elevation angle sequence (AZ1, EL1) - (AZn, ELn) during link establishment. The J2 model, HPOP and other orbital mechanics algorithms are used to ensure prediction accuracy, and finally the satellite transit trajectory is generated. Subsequently, the orbit calculation module 630 sends the satellite transit trajectory to the availability prediction module 640. (6) Link availability analysis.

[0138] The availability forecast module 640 overlays the satellite transit trajectory with the predicted sky cloud image corresponding to the cloud cover distribution prediction results, and analyzes the overlap and obstruction level between the line-of-sight link and the cloud-covered area by time slice. It generates the link availability results for the time period [T0, T1]. Subsequently, the availability results are sent to the interaction and reporting module 650.

[0139] (7) Link control decision support.

[0140] The interaction and reporting module 650 pushes the availability results to the optical station control system 710 to guide it in preparing for communication in advance. During unavailable periods, the link interruption process is planned in advance, and the link reconstruction and communication restoration operations are initiated immediately after the cloud and fog area is passed to ensure the accuracy of link control.

[0141] (8) Network resource scheduling and topology optimization.

[0142] The interaction and reporting module 650 simultaneously reports the availability results to the network management center 720, providing data support for the iterative planning of the entire network link. The network management center 720 can prepare for service flow distribution in advance. For example, when a site has an available microwave link, data can be switched to the microwave link 5 seconds before the laser communication link is interrupted to ensure the continuity of service transmission.

[0143] Based on the satellite-to-ground laser communication link availability prediction method shown in the above embodiments, this embodiment also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the method shown in the above embodiments.

[0144] Based on the methods shown in the above embodiments, this embodiment also provides a computer program product on which a computer program is stored, and when the computer program product is executed by a processor, it implements the methods shown in the above embodiments.

[0145] Based on this understanding, the technical solution of this application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, portable hard drive, etc.). The storage medium includes several instructions to cause a computer device (such as a personal computer, server, or network device, etc.) to execute the methods of the various embodiments of this application.

[0146] The storage medium may also include an operating system and a network communication module. The operating system is a program that manages the hardware and software resources of the aforementioned physical device, supporting the operation of information processing programs and other software and / or programs. The network communication module is used to enable communication between the various components within the storage medium, as well as communication with other hardware and software in the information processing physical device.

[0147] Based on the method shown in the above embodiments, and Figure 6 To achieve the above objectives, as illustrated in the virtual device embodiment, this application also provides an electronic device. This electronic device includes a storage medium and a processor; the storage medium stores a computer program; the processor executes the computer program to implement the method shown in the above embodiment.

[0148] Optionally, the aforementioned electronic device may also include a user interface, a network interface, a camera, radio frequency (RF) circuitry, sensors, audio circuitry, a Wi-Fi module, etc. The user interface may include a display screen, input units such as a keyboard, etc., and optionally, a USB interface, a card reader interface, etc. Optionally, the network interface may include standard wired interfaces, wireless interfaces (such as Wi-Fi interfaces), etc.

[0149] Those skilled in the art will understand that the physical device structure provided in this embodiment does not constitute a limitation on the physical device, and may include more or fewer components, or combine certain components, or have different component arrangements.

[0150] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented using software plus necessary general-purpose hardware platforms, or it can be implemented through hardware. This application addresses the technical problems of existing satellite cloud image-based ground-to-space laser communication forecasting schemes, such as deviations between long-term prediction results and actual field conditions, and the inability to simulate short-term cloud cover changes, leading to low satellite-to-space transmission efficiency and insufficient communication reliability. This application uses image acquisition equipment to collect real-time cloud image data above a ground optical station and predicts cloud cover changes during the satellite-to-space link establishment period based on the real-time cloud image data. Then, based on the target satellite orbital data and the physical location of the ground optical station, the satellite transit trajectory during the link establishment period is calculated. Finally, through the superposition analysis of cloud cover changes and satellite transit trajectories during the satellite-to-space link establishment period, accurate prediction of the availability of the satellite-to-space laser communication link is achieved.

[0151] Because image acquisition equipment features real-time on-site acquisition, it effectively avoids the inherent defects of large long-term prediction deviations in existing solutions, providing accurate on-site data support for cloud cover prediction. Predicting cloud cover changes during the period when satellite-to-ground links can be established based on real-time cloud image data effectively solves the problem of existing solutions being unable to adapt to short-term dynamic changes in cloud cover. Furthermore, by combining this with satellite transit trajectories, accurate prediction of satellite-to-ground laser communication link availability can be achieved. Based on this accurate prediction of satellite-to-ground laser communication link availability, this application can provide a scientific basis for control operations such as acquisition and tracking, link interruption and recovery at ground optical stations, and provide accurate data support for resource scheduling and topology optimization decisions in satellite-to-ground integrated networks. This significantly reduces sudden communication interruptions and data loss caused by cloud and fog interference, and significantly improves satellite-to-ground transmission efficiency, link availability, and the overall communication reliability of satellite-to-ground integrated networks.

[0152] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0153] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for predicting the availability of a satellite-to-ground laser communication link, characterized in that, include: Real-time cloud image data over the ground optical station is acquired using image acquisition equipment; Based on the real-time cloud map data, cloud cover changes are predicted during the period when satellite-to-ground link can be established, and cloud cover distribution prediction results are obtained. The satellite transit trajectory during the satellite-to-ground link establishment period is calculated based on the satellite orbital data of the target satellite and the physical location of the ground optical station. Based on the cloud cover distribution prediction results and the satellite transit trajectory, the availability results of the satellite-to-ground laser communication link are calculated; the availability results are used to generate control decisions for the satellite-to-ground laser communication link and resource scheduling and topology optimization decisions for the satellite-to-ground fusion network.

2. The method according to claim 1, characterized in that, The real-time cloud image data includes visible light images of the entire airspace above the ground optical station, as well as spatial distribution information of meteorological parameters extracted from the visible light images; The prediction of cloud cover changes during the satellite-to-ground link establishment period based on the real-time cloud image data, to obtain cloud cover distribution prediction results, includes: Based on the real-time cloud map data, the movement vector, coverage area and distribution pattern changes of cloud clusters during the time period when satellite-to-ground link can be established are dynamically simulated and predicted using a preset extrapolation algorithm, and the cloud distribution prediction results are obtained.

3. The method according to claim 1 or 2, characterized in that, The satellite orbit-related data includes the number of roots in two rows of the satellite; The satellite transit trajectory during the satellite-to-ground link-establishable period is calculated based on the target satellite's orbital data and the physical location of the ground optical station, including: Using the two rows of satellite roots of the target satellite as input, the spatial position and motion state data of the target satellite during the period when the satellite-to-ground link can be established are predicted using an orbital mechanics algorithm; Based on the physical location of the ground optical station and the spatial location and motion state data of the target satellite, the pointing vector required for the ground optical station to align with the target satellite is calculated; The pointing vector is converted into a pointing angle sequence of the ground optical station during the satellite-to-ground link establishment period, and the satellite trajectory data corresponding to the pointing angle sequence is extracted; The satellite trajectory data is converted into a coordinate system consistent with the cloud cover distribution prediction results to obtain the satellite transit trajectory.

4. The method according to claim 3, characterized in that, The satellite orbit-related data includes the current position information of the target satellite; The method further includes: The current location information of the target satellite is obtained in real time through the Beidou short message transceiver module; Using the satellite root number of the target satellite and the current position information as input, the orbital mechanics algorithm is used to predict the spatial position and motion status data of the target satellite during the period when the satellite-to-ground link can be established.

5. The method according to claim 1 or 2, characterized in that, The availability result of the satellite-to-ground laser communication link is calculated based on the cloud cover distribution prediction result and the satellite transit trajectory, including: The satellite transit trajectory is superimposed with the predicted cloud map data corresponding to the cloud cover distribution prediction result to obtain the spatial location of the line-of-sight link corresponding to the satellite transit trajectory in the predicted cloud map data. Based on the spatial location of the line-of-sight link corresponding to the satellite transit trajectory in the predicted cloud image data, the overlap analysis results are determined; the overlap analysis results characterize the degree of overlap and occlusion between the line-of-sight link corresponding to the satellite transit trajectory and the cloud-covered area in the predicted cloud image data during the satellite-to-ground link establishment period. Based on the overlap analysis results, it is determined whether the target satellite and the ground optical station meet the laser communication transmission conditions during the satellite-to-ground link establishment period, and the availability result is generated.

6. The method according to claim 5, characterized in that, After obtaining the spatial location of the line-of-sight link corresponding to the satellite transit trajectory in the predicted cloud image data, the method further includes: The time period during which a satellite-to-ground link can be established is divided into multiple consecutive time slices; Within each time slice, determine the degree of overlap between the line-of-sight link corresponding to the satellite transit trajectory and the cloud-covered area in the predicted cloud image data, as well as the degree of occlusion, to obtain the overlap analysis results corresponding to each time slice; Based on the overlap analysis results corresponding to each time slice, it is determined whether the target satellite and the ground optical station meet the laser communication transmission conditions within each time slice, and an availability result with the time slice as the granularity is generated.

7. The method according to claim 1 or 2, characterized in that, After calculating the availability of the satellite-to-ground laser communication link, the method further includes: The availability result is sent to the ground optical station control system; the availability result is used to guide the ground optical station control system to generate the satellite-to-ground laser communication link control decision, and the satellite-to-ground laser communication link control decision is used to control the ground optical station to perform link control related operations.

8. The method according to claim 1 or 2, characterized in that, After calculating the availability of the satellite-to-ground laser communication link, the method further includes: The availability results are reported to the network control center; the availability results are used to guide the network control center in making resource scheduling and topology optimization decisions for the satellite-ground integrated network.

9. A satellite-to-ground laser communication link availability prediction device, characterized in that, include: The cloud acquisition module is configured to acquire real-time cloud image data over the ground optical station through image acquisition equipment; The cloud cover prediction module is configured to predict cloud cover changes during the period when satellite-to-ground link can be established based on the real-time cloud map data, and obtain cloud cover distribution prediction results. The orbit calculation module is configured to calculate the satellite transit trajectory during the satellite-to-ground link-establishment period based on the satellite orbit-related data of the target satellite and the physical location of the ground optical station. The availability forecast module is configured to calculate the availability result of the satellite-to-ground laser communication link based on the cloud distribution prediction result and the satellite transit trajectory; the availability result is used to generate control decisions for the satellite-to-ground laser communication link and resource scheduling and topology optimization decisions for the satellite-to-ground fusion network.

10. A satellite-to-ground laser communication link availability prediction system, characterized in that, It includes at least the satellite-to-ground laser communication link availability prediction device, ground optical station control system, network management center, and ground optical station as described in claim 9; wherein, The satellite-to-ground laser communication link availability prediction device performs the satellite-to-ground laser communication link availability prediction method as described in any one of claims 1-8; The ground optical station control system is configured to receive availability results sent by the satellite-to-ground laser communication link availability prediction device, and generate satellite-to-ground laser communication link control decisions based on the availability results. The network control center is configured to receive availability results sent by the satellite-to-ground laser communication link availability prediction device, and generate resource scheduling and topology optimization decisions for the satellite-to-ground fusion network based on the availability results. The ground optical station is configured to receive satellite-to-ground laser communication link control decisions from the ground optical station control system and to perform link control-related operations based on the satellite-to-ground laser communication link control decisions.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 8.

12. An electronic device comprising a storage medium, a processor, and a computer program stored on the storage medium and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of any one of claims 1 to 8.

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