Satellite handover method, electronic device, storage medium, and program product

Abstract

The application provides a satellite switching method, an electronic device, a storage medium and a program product, and relates to the technical field of communication. The method autonomously acquires actual attitude information of a phased array antenna on the terminal side, determines the visibility of each candidate satellite relative to the antenna beam scanning range based on the attitude information in combination with ephemeris information and position information, obtains a satellite set actually visible to the antenna, and reports the satellite set to the network side, so that the network side switching decision is established on the basis of the real communication capability of the terminal rather than the traditional geometric visibility assumption, the situation that the geometric visibility does not match the antenna visibility caused by the non-horizontal installation of the phased array antenna and the continuous attitude changes such as rolling, pitching and yawing in the process of carrier movement is effectively eliminated, the network side selects a satellite that cannot communicate with the terminal as a switching target is avoided, and the switching success rate is effectively improved.

Description

Technical Field

[0001] This application relates to the field of communication technology, and more specifically, to a satellite switching method, electronic device, storage medium, and program product. Background Technology

[0002] In low-Earth orbit (LEO) satellite communication systems, satellites move at high speeds relative to ground terminals, requiring terminals to frequently switch between different satellites to maintain communication link continuity. Existing satellite handover schemes typically employ the following handover process: The terminal first acquires its own location information and reports it to the currently serving satellite; upon receiving the terminal's reported location information, the satellite network, in conjunction with its stored satellite ephemeris data, calculates the visibility of each candidate satellite relative to the terminal's location, selecting a set of visible satellites; the network then chooses one from this set as the target handover satellite; finally, the current serving satellite and the target handover satellite execute a standard inter-satellite handover signaling procedure to complete the communication link transfer.

[0003] In the existing scheme described above, the terminal only reports its location information to the network. The network determines satellite visibility using a geometric visibility criterion: a satellite is considered visible if it is above the terminal's local horizontal plane. This method implicitly assumes that the terminal's receiving antenna plane is approximately parallel to the local horizontal plane, and its normal direction approximately points towards the zenith. Under this assumption, the geometric visibility of the satellite is essentially consistent with the actual coverage visibility of the antenna. Therefore, the handover target selected by the network based on geometric visibility is usually successfully connected to by the terminal, resulting in a high handover success rate.

[0004] However, in certain special scenarios, the above implicit assumptions do not hold true at all, leading to problems with satellite switching based on geometric visibility. For example, in a rocket launch scenario, the phased array antenna plane is mounted flush against the outer surface of the rocket body. Since the rocket body has a cylindrical structure, the phased array antenna plane cannot be mounted horizontally, resulting in a significant deviation between its normal direction and the zenith direction, with tilt angles reaching 30° to 60° or even greater, up to 90°. Furthermore, the rocket experiences continuous attitude changes during flight, such as roll, pitch, and yaw, causing the angle between the antenna plane and the horizontal plane to change dynamically. In the above scenarios, due to the significant and dynamically changing angle between the actual pointing of the antenna and the horizontal plane, two critical situations arise that traditional geometric visibility determination methods cannot handle: Situation 1 is geometrically visible but antenna invisible, that is, although some satellites are above the terminal's horizontal plane (determined to be visible by traditional methods), because the antenna plane is tilted to one side, the elevation angle of the satellite relative to the antenna plane exceeds the antenna beam scanning range, and the terminal cannot actually communicate with it; Situation 2 is geometrically invisible but antenna visible, that is, although some satellites are below the terminal's horizontal plane (determined to be invisible by traditional methods), because the antenna plane is tilted to the other side, the satellite happens to fall within the antenna beam scanning range, and the terminal can actually communicate with it, but traditional methods miss these types of available satellites.

[0005] Because the terminal only reports location information, there is a discrepancy between the geometrically visible satellite set calculated by the network and the actual satellite set visible to the terminal's antenna. For example, when the network selects a satellite as the handover target in scenario one, the terminal cannot establish a communication link on the new satellite, resulting in handover failure. After a handover failure, the terminal needs to wait for a timeout and reselect, causing communication interruption. Summary of the Invention

[0006] The purpose of this application is to provide a satellite switching method, electronic device, storage medium, and program product to improve the problem in the prior art where the geometrically visible satellite set calculated by the network side is inconsistent with the actual antenna visible satellite set of the terminal because the terminal only reports location information.

[0007] In a first aspect, embodiments of this application provide a satellite handover method applied to a satellite communication terminal, wherein the phased array antenna of the satellite communication terminal is mounted on the surface of a mobile carrier, and the method includes: Acquire the attitude information of the phased array antenna, the ephemeris information of each candidate satellite, and the location information of the satellite communication terminal; Based on the attitude information, the ephemeris information, and the position information, the visibility of each candidate satellite relative to the beam scanning range of the phased array antenna is determined, and the set of satellites visible to the antenna is obtained. Send visible satellite information to the currently serving satellite, wherein the visible satellite information includes the set of visible satellites of the antenna, and the currently serving satellite is used to select a target switching satellite from the set of visible satellites of the antenna.

[0008] In the above implementation process, the terminal autonomously acquires the actual attitude information of the phased array antenna, and determines the visibility of each candidate satellite relative to the antenna beam scanning range based on this attitude information combined with ephemeris information and position information. This results in the set of satellites that are actually visible to the antenna and reports it to the network side. This allows the network side to make handover decisions based on the actual communication capabilities of the terminal rather than the traditional geometric visibility assumptions. This effectively eliminates the mismatch between geometric visibility and antenna visibility caused by the phased array antenna not being installed horizontally and by continuous attitude changes such as roll, pitch, and yaw during carrier movement. It also avoids the network side selecting satellites that the terminal cannot communicate with as handover targets, effectively improving the handover success rate.

[0009] Secondly, embodiments of this application provide a satellite handover method applied to a satellite base station, the method comprising: Acquire visible satellite information sent by a satellite communication terminal, wherein the visible satellite information includes the set of visible satellites of the antenna, and the set of visible satellites of the antenna is determined by the satellite communication terminal according to the method provided in the first aspect above; Target switching satellites are selected from the set of visible satellites according to a preset strategy; The process of switching between the current serving satellite and the target switching satellite of the satellite communication terminal is executed.

[0010] Thirdly, embodiments of this application provide an electronic device, including a processor and a memory, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the steps of the method provided in the first or second aspect above are performed.

[0011] Fourthly, embodiments of this application provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, performs the steps of the methods provided in the first or second aspect above.

[0012] Fifthly, embodiments of this application provide a computer program product, including computer program instructions, which, when read and executed by a processor, perform the steps in the methods provided in the first or second aspects above.

[0013] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing embodiments of this application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 A flowchart illustrating a satellite handover method provided in this application embodiment; Figure 2 A flowchart of another satellite handover method is provided for embodiments of this application; Figure 3 This application provides a structural block diagram of a satellite switching device according to an embodiment; Figure 4 This is a schematic diagram of the structure of an electronic device for performing a satellite handover method, provided as an embodiment of this application. Detailed Implementation

[0016] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0017] It should be noted that the terms "system" and "network" in the embodiments of this invention can be used interchangeably. "Multiple" refers to two or more; therefore, in the embodiments of this invention, "multiple" can also be understood as "at least two". "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the preceding and following related objects have an "or" relationship.

[0018] It should also be noted that all actions involving the acquisition of signals, information, or data in this application are carried out in compliance with the relevant data protection laws and policies of the country where the application is located, and with the authorization granted by the owner of the relevant device.

[0019] The satellite handover method provided in this application autonomously acquires the actual attitude information of the phased array antenna on the terminal side, and determines the visibility of each candidate satellite relative to the antenna beam scanning range based on the attitude information combined with ephemeris information and position information. This results in a set of satellites that are actually visible to the antenna and reports it to the network side. This allows the network side to make handover decisions based on the actual communication capabilities of the terminal rather than traditional geometric visibility assumptions. This effectively eliminates the mismatch between geometric visibility and antenna visibility caused by the phased array antenna not being installed horizontally and by continuous attitude changes such as roll, pitch, and yaw during carrier movement. It also avoids the network side selecting satellites that the terminal cannot communicate with as handover targets, effectively improving the handover success rate.

[0020] This application provides a satellite handover method applied to a satellite communication terminal, where the phased array antenna is mounted on the surface of a mobile carrier. Phased array antennas are typically conformally mounted to the carrier surface, resulting in a deviation between the antenna's normal direction and the zenith direction. In some special scenarios, such as rocket launches, the mounting plane of the phased array antenna may have a non-zero angle with the horizontal reference plane of the mobile carrier.

[0021] In this context, a satellite communication terminal refers to a communication device mounted on a mobile carrier and capable of communicating with Earth-orbiting satellites. It includes at least a phased array antenna, a radio frequency transceiver unit, and a baseband processing unit. For simplicity, it will be referred to as a terminal in some subsequent embodiments.

[0022] A phased array antenna is an antenna system that achieves beam scanning by controlling the feed phase of each radiating element in the array antenna. Its beam pointing can be changed quickly without relying on mechanical rotation. The beam scanning range is limited by the antenna array element layout and the performance of the phase shifter.

[0023] Mobile carriers refer to platforms that carry satellite communication terminals and are in spatial motion, including but not limited to rockets, missiles, aircraft, drones, ships, or other platforms that undergo attitude changes during operation.

[0024] The horizontal reference plane is the horizontal plane that is perpendicular to the direction of gravity, i.e., the local horizontal plane.

[0025] The antenna mounting plane refers to the geometric abstraction of the plane where the phased array antenna elements are located, and its normal direction is the direction of the antenna beam scanning center axis.

[0026] Please refer to Figure 1 , Figure 1 A flowchart of a satellite handover method provided in this application embodiment, the method including the following steps: Step S110: Obtain the attitude information of the phased array antenna, the ephemeris information of each candidate satellite, and the location information of the satellite communication terminal.

[0027] Because, for example, the phased array antenna of a rocket is installed close to the surface of the rocket body, there is an angle between the antenna plane and the horizontal plane, and the attitude of the rocket changes continuously during flight, only by obtaining the actual spatial attitude of the phased array antenna can we accurately calculate which satellites fall within the antenna beam scanning range.

[0028] Attitude information refers to data used to describe the orientation of a phased array antenna in three-dimensional space, which may include the antenna normal vector, Euler angles, quaternions or other equivalent attitude expressions.

[0029] Ephemeris information refers to data used to describe the orbital status of a satellite, including but not limited to Keplerian orbital elements, two-line orbital elements, or ephemeris parameters broadcast by satellite navigation systems.

[0030] The attitude information of a phased array antenna is used to characterize the actual orientation of the antenna plane in space. Specifically, the antenna normal direction vector can be used as the quantized form of attitude information. This normal direction vector is obtained as follows: the terminal acquires the roll angle, pitch angle, and yaw angle output by the attitude sensors installed on the mobile vehicle, then acquires the installation azimuth angle and installation pitch angle of the phased array antenna on the mobile vehicle, and constructs a coordinate rotation matrix of the array surface coordinate system relative to the navigation coordinate system based on the roll angle, pitch angle, yaw angle, installation azimuth angle, and installation pitch angle, and then obtains the normal direction vector of the phased array antenna based on the coordinate rotation matrix. The attitude information of the phased array antenna includes the normal direction vector.

[0031] This scheme involves several coordinate systems, including the navigation coordinate system, the carrier coordinate system, and the array coordinate system.

[0032] The navigation coordinate system (N-system), also known as ENU (East-North-Up), has its origin at the terminal location, and X... N The axis points geographically east, Y N The axis points north, Z N The axis points towards the zenith and is used to describe the absolute spatial orientation of the carrier and the target.

[0033] The carrier coordinate system (B system) takes the center of mass of the carrier (such as a rocket) as its origin, X B The axis points towards the head of the carrier, Y B The axis points to the right side of the carrier, Z B The axes are determined by the right-hand rule, and each axis is fixed to the carrier to describe the spatial attitude of the carrier itself.

[0034] The array coordinate system (A-frame) has its origin at the center of the antenna plane, and Z... A The axis is the antenna normal direction (beam scanning center direction), X A axis and Y AThe axis lies in the antenna plane and is used to describe the incident azimuth of the satellite signal relative to the antenna plane.

[0035] Roll angle This refers to the carrier rotating around its own longitudinal axis (X). B The angle of rotation of the axis reflects the rolling state of the carrier around the forward direction.

[0036] The pitch angle θ refers to the angle between the longitudinal axis of the carrier and the horizontal plane, such as the angle between the longitudinal axis of the rocket and the horizontal plane, reflecting the degree to which the rocket body pitches up or down.

[0037] Yaw angle It refers to the angle between the projection of the vehicle's longitudinal axis onto the horizontal plane and the northward direction of the navigation coordinate system, reflecting the vehicle's heading in the horizontal plane.

[0038] Installation azimuth angle α inst It is the antenna plane reference direction (e.g., X). A (axis) on carrier X B -Y B Projection on the plane and carrier X B The included angle between the axes is used to determine the circumferential mounting position of the antenna on the carrier.

[0039] Install pitch angle β inst The antenna normal direction is relative to the carrier X. B The angle between the axes, β when the antenna normal points radially towards the carrier. inst =90°, used to determine the degree of tilt of the antenna relative to the longitudinal axis of the carrier.

[0040] A coordinate rotation matrix is ​​a mathematical matrix used to describe the rotational transformation relationship between two coordinate systems. It can be used to transform vector coordinates in one coordinate system to another.

[0041] The normal direction vector is a unit vector perpendicular to the phased array antenna plane. Its direction is the direction of the antenna beam scanning center axis and is the core parameter characterizing the spatial orientation of the antenna.

[0042] Specifically, the terminal can read the roll angle of the mobile carrier in real time through attitude sensors such as inertial navigation systems, inertial measurement units, or attitude heading reference systems installed on the mobile carrier. Pitch angle θ and yaw angle These are motion attitude parameters, which describe the spatial orientation of the vehicle coordinate system relative to the navigation coordinate system.

[0043] Simultaneously, the terminal reads the pre-stored installation parameters of the phased array antenna on the mobile carrier, including the installation azimuth angle α. inst and installation pitch angle β instThese two parameters are determined through precise measurements after the antenna is installed on the carrier and are fixed values. Then, the terminal constructs a rotation matrix between the array coordinate system (A-frame) and the carrier coordinate system (B-frame) based on the installation parameters. ,in and These are the basic rotation matrices around the Y-axis and Z-axis, respectively.

[0044] The terminal constructs a rotation matrix of the carrier coordinate system relative to the navigation coordinate system based on the real-time acquired rocket attitude angles: ,in Let X be the fundamental rotation matrix about the X-axis. Then, multiply the two rotation matrices above to obtain the total rotation matrix of the array coordinate system relative to the navigation coordinate system, i.e., the coordinate rotation matrix: .

[0045] Due to the Z-axis of the array coordinate system A The axis is the normal direction of the antenna plane, and the terminal will rotate the total matrix. With respect to the normal unit vector [0,0,1] T Multiplication, i.e., n array = ·[0,0,1] T The normal direction vector of the phased array antenna is obtained in the navigation coordinate system, and this normal direction vector is the attitude information of the phased array antenna in this embodiment. After the terminal obtains this normal direction vector, it can be used in subsequent steps to transform the direction vectors of each candidate satellite from the navigation coordinate system to the array surface coordinate system in order to determine whether the satellite falls within the antenna beam scanning range.

[0046] In addition, the ephemeris information of each candidate satellite refers to the orbital data of each communication satellite in the satellite network. The terminal can receive it through the downlink broadcast channel of the currently serving satellite or through the data link of the ground control center. The ephemeris information is used to calculate the real-time position of each candidate satellite in space.

[0047] The location information of a terminal refers to its geographical location in space. It can be obtained through satellite navigation receivers (such as GPS (Global Positioning System) / BDS (BeiDou Navigation Satellite System) / GLONASS (Global Navigation Satellite System)) or calculated through an inertial navigation system when navigation signals are limited.

[0048] Step S120: Based on attitude information, ephemeris information and position information, determine the visibility of each candidate satellite relative to the beam scanning range of the phased array antenna, and obtain the set of satellites visible to the antenna.

[0049] Among them, visible satellites refer to satellites whose beams of phased array antennas can effectively cover the direction of the satellite and whose antenna gain can meet the communication link budget requirements.

[0050] In practice, the terminal calculates the position of each candidate satellite in space based on ephemeris information and, combined with its own position information, calculates the direction vector of each candidate satellite relative to the terminal. Then, based on the attitude information of the phased array antenna, the terminal transforms this direction vector into an array coordinate system with the antenna plane as a reference, obtaining the spatial azimuth of each candidate satellite relative to the antenna plane. Finally, the terminal compares the spatial azimuth of each candidate satellite with the beam scanning range of the phased array antenna. When the spatial azimuth of a candidate satellite falls within the beam scanning range, the candidate satellite is determined to be a visible satellite; otherwise, it is determined to be an invisible satellite. The beam scanning range is determined by the hardware capabilities of the phased array antenna, specifically the maximum scanning angle range that the antenna beam can deviate from the normal direction, including the elevation scanning range and the azimuth scanning range.

[0051] The terminal iterates through all candidate satellites and adds all satellites that are determined to be visible to the antenna to the set of visible satellites.

[0052] Step S130: Send visible satellite information to the currently serving satellite.

[0053] The visible satellite information includes the set of satellites visible to the antenna, such as a list of satellite numbers. The currently serving satellite is used to select a target switching satellite from the set of visible satellites. The currently serving satellite is the satellite on which the terminal is currently maintaining a communication link connection, while the target switching satellite is the satellite selected by the network side to take over from the currently serving satellite and continue providing communication services.

[0054] After receiving the information from the visible satellite, the current serving satellite selects a target switching satellite from the set of visible satellites and executes a switching signaling procedure with the target switching satellite to switch the terminal to the target satellite to maintain the continuity of the communication link.

[0055] In the above implementation process, the terminal side autonomously senses the attitude of the phased array antenna and calculates the actual set of satellites visible to the antenna. The visibility determination result is then reported to the network side, so that the handover decision of the network side is based on the actual communication capability of the terminal. This effectively avoids the handover failure problem caused by the antenna installation tilt or changes in the carrier attitude, where the antenna is geometrically visible but not visible, thus improving the handover success rate.

[0056] Based on the above embodiments, in determining the visibility of each candidate satellite relative to the beam scanning range of the phased array antenna, the position vector of each candidate satellite relative to the satellite communication terminal can be calculated first based on ephemeris information and position information. Then, the elevation angle and azimuth angle of each candidate satellite relative to the phased array antenna plane can be calculated based on attitude information and position vector. Finally, the set of visible satellites can be determined from each candidate satellite based on the elevation angle, azimuth angle and the beam scanning range of the phased array antenna.

[0057] First, the terminal calculates the position vector of each candidate satellite relative to the satellite communication terminal based on the acquired ephemeris and position information. Specifically, the terminal calculates the satellite position of each candidate satellite in the Earth-Centered, Earth-Fixed (ECEF) coordinate system based on the ephemeris information of each candidate satellite. This can be achieved using standard orbit extrapolation algorithms (such as analytical methods or numerical integration methods based on Kepler orbital elements) to calculate the spatial position of each candidate satellite in the ECEF. Simultaneously, the terminal obtains its own position P in the ECEF coordinate system through a satellite navigation receiver or inertial navigation system. terminal Then, the terminal calculates the position difference vector between each candidate satellite and its own position based on the satellite positions and the terminal's own position. Then, based on the latitude and longitude of the terminal's location, a coordinate transformation matrix is ​​constructed from the ECEF coordinate system to the terminal's local navigation coordinate system (ENU coordinate system). The position difference vector is transformed into the terminal's navigation coordinate system (ENU) using a coordinate transformation matrix, thus obtaining the position vector of each candidate satellite in the terminal's local ENU coordinate system. This position vector represents the spatial distribution of each candidate satellite relative to the terminal in the east, north, and zenith directions.

[0058] Secondly, based on the attitude information and position vectors obtained above, the terminal calculates the elevation and azimuth angles of each candidate satellite relative to the phased array antenna plane. Specifically, since the beam scanning range of the phased array antenna is defined relative to the normal direction of the antenna plane, only the elevation and azimuth angles calculated in the array plane coordinate system can accurately reflect whether the satellite is within the beam coverage area. Therefore, the terminal first utilizes the acquired phased array antenna attitude information, i.e., the total rotation matrix from the navigation coordinate system to the array plane coordinate system. The position vectors of each candidate satellite are transformed from the ENU coordinate system to the array surface coordinate system to obtain the direction vectors of each candidate satellite in the array surface coordinate system. This direction vector is represented in the array coordinate system as Based on this, for any candidate satellite k, the terminal determines the direction vector based on its Z-axis component in the array coordinate system. With vector magnitude || The ratio of || is used to calculate the elevation angle of the candidate satellite relative to the normal direction of the phased array antenna plane, i.e. The elevation angle reflects the degree to which the satellite's orientation deviates from the antenna's normal direction. A larger elevation angle indicates that the satellite is closer to the antenna's normal direction (i.e., directly above the antenna). When the elevation angle is 90°, the satellite is located in the antenna's normal direction. Simultaneously, the terminal uses the X-axis component of the candidate satellite's orientation vector in the array coordinate system... and Y-axis components The azimuth angle of the satellite relative to the reference direction of the antenna plane is calculated using the arctangent function in the four quadrants. This azimuth angle reflects the direction of the satellite's projection onto the antenna plane.

[0059] Finally, based on the calculated elevation and azimuth angles of each candidate satellite, and the pre-stored phased array antenna beam scanning range parameters, the terminal determines the set of satellites visible to the antenna from among the candidate satellites. The beam scanning range of the phased array antenna is determined by the antenna hardware capabilities, specifically including the maximum scanning elevation angle. and maximum scan azimuth angle (For example, both are ±60°). The terminal's decision logic is as follows: for any candidate satellite k, if the elevation angle is greater than or equal to the first threshold and the absolute value of the azimuth angle is less than or equal to the second threshold, then the candidate satellite is added to the antenna's visible satellite set. The first threshold is determined based on the maximum scanning elevation angle within the beam scanning range, and the second threshold is determined based on the maximum scanning azimuth angle within the beam scanning range.

[0060] The first threshold is the elevation angle threshold, which is the angle threshold used to determine whether a satellite falls within the coverage area of ​​the antenna's elevation beam. Its value can be equal to 90° minus the maximum scanning elevation angle. The elevation angle of the satellite relative to the antenna plane must be greater than or equal to this threshold to ensure that the deviation of the satellite's direction from the antenna's normal direction does not exceed the antenna's maximum scanning capability in the elevation dimension.

[0061] The second threshold is the azimuth threshold, which is an angle threshold used to determine whether a satellite falls within the coverage area of ​​the antenna azimuth beam. Its value can be equal to the maximum scanning azimuth angle. The absolute value of the azimuth angle of the satellite relative to the antenna plane reference direction must be less than or equal to this threshold to ensure that the satellite's direction is within the antenna azimuth scanning boundary.

[0062] The beam scanning range refers to the spatial angular range that a phased array antenna can reach when it achieves beam pointing electronically by controlling the feed phase of each array element. It is determined by the antenna's hardware design parameters (array element layout, phase shifter range, array element spacing, etc.) and usually includes two dimensions: elevation scanning range and azimuth scanning range.

[0063] Maximum scan pitch angle This refers to the maximum elevation angle by which the antenna beam can deviate from the antenna's normal direction, reflecting the antenna's scanning capability in the elevation dimension. The larger this value, the wider the antenna's elevation coverage range; it is typically taken as 60°~75°.

[0064] Maximum scanning azimuth angle This refers to the maximum angle by which the antenna beam deviates from the reference direction in the azimuth direction, reflecting the antenna's scanning capability in the azimuth dimension. The larger this value, the wider the antenna's azimuth coverage area; it is generally taken as ±60° to ±90°.

[0065] Specifically, the terminal is based on the maximum scanning pitch angle. Determine the first threshold =90°- According to the maximum scanning azimuth angle Determine the second threshold (That is, the azimuth threshold is the maximum scanning azimuth itself). When the elevation angle of candidate satellite k... Greater than or equal to the first threshold And the azimuth angle of the satellite The absolute value is less than or equal to the second threshold. When the terminal determines that the spatial azimuth of the candidate satellite falls within the beam scanning range of the phased array antenna, it is considered a visible satellite and is added to the visible satellite set S. vis Conversely, if either of the above two conditions is not met—that is, the elevation angle is less than the first threshold or the absolute value of the azimuth angle is greater than the second threshold—then the candidate satellite is determined to be outside the antenna beam scanning range, belonging to the antenna-invisible satellites, and is not added to the set. The terminal traverses all candidate satellites according to the above determination logic, and includes all satellites that meet the conditions into the antenna-visible satellite set. .

[0066] It should be noted that both of the above conditions must be met simultaneously for the satellite to be visible to the antenna; neither can be omitted. The elevation angle condition ensures that the satellite has a sufficient elevation angle relative to the antenna plane to fall within the beam's elevation coverage area, while the azimuth angle condition ensures that the satellite's azimuth direction within the antenna plane does not exceed the beam's azimuth scanning boundary. For example, the maximum scanning elevation angle of a typical phased array antenna... Taking 60° as an example, the first threshold =30°, meaning the satellite's elevation angle relative to the antenna plane must be at least 30° to be covered by the antenna beam; if the maximum scanning azimuth angle If the elevation angle is 60°, then the satellite's azimuth angle must fall within the range of [-60°, +60°]. When any candidate satellite simultaneously satisfies that its elevation angle is greater than or equal to 30° and its absolute azimuth angle is less than or equal to 60°, the satellite is determined to be a visible satellite.

[0067] Furthermore, in practical implementation, the terminal can optimize the above-mentioned judgment process. For example, before traversing candidate satellites, the terminal can first calculate the elevation angle of the satellite in the navigation coordinate system based on the satellite's position vector relative to the terminal, and pre-select satellites with an elevation angle below 0° (i.e., below the horizontal plane), because these satellites will inevitably be blocked by the Earth and will not be visible, thus eliminating the need for subsequent array coordinate transformation and judgment, thereby reducing the amount of computation. As another example, the terminal can pre-select satellites whose distance exceeds a preset threshold, because their signal propagation loss is too high, and even if the antenna is visible, the communication link budget requirements cannot be met.

[0068] In the above implementation process, firstly, the spatial position vector of each candidate satellite relative to the terminal is calculated based on ephemeris and position information, converting the absolute spatial position of the satellite into a relative azimuth with the terminal as the reference. Then, based on the actual attitude information of the phased array antenna, the position vector is transformed from the navigation coordinate system to the array plane coordinate system, and the elevation and azimuth angles of each satellite relative to the antenna plane are calculated, thereby accurately associating the spatial azimuth of the satellite with the actual orientation of the antenna. Finally, based on the beam scanning range determined by the antenna hardware capabilities, the elevation and azimuth angles are used as the judgment dimensions to accurately select all candidate satellites whose spatial azimuth falls within the antenna beam coverage area to form the antenna visible satellite set. This achieves accurate calculation of the actual coverage area of ​​the antenna, solving the problem of inaccurate judgment caused by relying solely on geometric position for visibility judgment in traditional schemes that ignore antenna attitude. This ensures the accuracy and reliability of the antenna visible satellite set, providing a reliable candidate set basis for subsequent network-side handover decisions and avoiding handover failures caused by selecting actually invisible satellites.

[0069] Based on the above embodiments, the visible satellite information sent by the terminal to the currently serving satellite may include the identification information of each visible satellite in the antenna visible satellite set and auxiliary handover information. The auxiliary handover information includes at least one of the following: the azimuth information of each visible satellite relative to the phased array antenna and the signal quality information of each visible satellite.

[0070] The identification information is used to uniquely identify each visible satellite, enabling the network side to clearly know which satellites are available for handover; the auxiliary handover information provides the network side with a more comprehensive decision-making reference when selecting target handover satellites, helping the network side to comprehensively evaluate the advantages and disadvantages of each candidate satellite from multiple dimensions.

[0071] In the visible satellite information sent by the terminal, the identification information of the set of visible satellites can be specifically in the form of a list of unique numbers of each visible satellite in the network, such as S. vis ={k1,k2,…,k m}, where m is the total number of satellites visible to the antenna. After receiving this list of numbers, the network side can query the ephemeris status, load status, available resources, and other information of each satellite according to the number, thereby performing an initial screening of the target for switching within the set of visible satellites.

[0072] Based on the above, the visible satellite information sent by the terminal may also include auxiliary handover information, which includes at least one of the following types: azimuth information of each visible satellite relative to the phased array antenna, and signal quality information of each visible satellite.

[0073] First, the azimuth information of each visible satellite relative to the phased array antenna. The terminal can report the elevation and azimuth angles of each visible satellite calculated in step S120 as auxiliary information, i.e., in the form of data pairs ( , It provides the spatial azimuth distribution of each satellite in the array coordinate system. This azimuth information allows the network side to predict the spatial positional relationship of each satellite relative to the antenna orientation: the larger the elevation angle, the closer the satellite is to the antenna normal direction, and the higher the signal reception gain is usually; the azimuth angle reflects the degree of satellite offset in the horizontal direction. Combined with the terminal attitude change trend, the network side can infer the direction of signal quality change of each satellite in the future, which helps to select a more sustainable switching target.

[0074] Secondly, signal quality information for each visible satellite. The terminal can measure the downlink signal quality indicators of each visible satellite and report them as auxiliary information. Specifically, this may include one or more metrics such as reference signal received power, reference signal received quality, signal-to-noise ratio, and signal strength indication. The terminal can sequentially measure the signal quality in the direction of each visible satellite through the multi-beam receiving capability of the phased array antenna or through beam scanning, and report the measurement results in the form of data pairs (…). Reported, among which Indicates satellite The signal quality metric. This signal quality information allows the network to directly know the actual communication conditions of each candidate satellite, which helps to select the handover target with the best signal quality and avoid selecting satellites that are within the antenna's visible range but whose signals are blocked or interfered with.

[0075] When reporting, the terminal can flexibly choose the combination of the above auxiliary information based on the uplink channel bandwidth resources and network requirements: In bandwidth-constrained scenarios, the terminal can only report a list of visible satellite numbers, minimizing signaling overhead, and the network can query other information based on the numbers; in bandwidth-sufficient scenarios, the terminal can report a complete combination of numbers, azimuth information, and signal quality information, providing the network with the most comprehensive decision-making basis. The terminal's reporting content configuration can be dynamically adjusted through configuration commands issued by the network to adapt to the needs of different communication scenarios and network strategies.

[0076] Furthermore, the terminal can send the aforementioned auxiliary information along with the identification information of the visible satellite set in the same reporting message, using a type-length-value format to flexibly encode each field, facilitating network-side parsing and expansion. Upon receiving the visible satellite report containing auxiliary handover information, the network side can comprehensively consider multiple factors such as signal quality, spatial orientation, satellite payload, and estimated service duration to optimally select the target handover satellite from the antenna's visible satellite set, achieving a more precise and optimized handover decision.

[0077] In the above implementation process, the visible satellite information reported by the terminal may also include auxiliary handover information such as the azimuth information and / or signal quality information of each visible satellite. The azimuth information enables the network side to know the specific spatial distribution of each satellite within the antenna beam coverage area. Combined with the movement trend of the mobile vehicle, it can predict the future direction of signal quality changes and service continuity of each satellite, thereby selecting target satellites that meet current communication needs and have a longer service duration, reducing frequent handovers. The signal quality information enables the network side to make selections based on measured link data rather than ideal calculations, avoiding evaluation biases caused by factors such as ephemeris errors, obstruction, or interference, and accurately selecting target satellites with the best signal quality.

[0078] Based on the above embodiments, before sending visible satellite information, the terminal first determines whether the preset reporting conditions are met. Only after determining that the reporting conditions are met will the terminal trigger the sending of visible satellite information to the currently serving satellite. The reporting conditions include at least one of the following, and the terminal can use a single condition or a combination of multiple conditions according to the actual configuration.

[0079] (1) Periodic Triggered Reporting. The terminal periodically reports visible satellite information according to a preset time interval. The length of this period can be dynamically adjusted according to the flight phase of the mobile vehicle. For example, during the rocket's ascent or reentry phases, when attitude changes drastically, the reporting period is shortened (e.g., 1-2 seconds) to ensure that the network side obtains the latest visible satellite information in a timely manner; during the gliding phase, when attitude is relatively stable, the reporting period is extended (e.g., 5-10 seconds) to save uplink signaling bandwidth. The reporting period can be remotely configured by the ground control center or the network side through commands to adapt to the needs of different mission phases.

[0080] (2) Reporting is triggered in response to the signal strength of the currently serving satellite falling below a preset threshold. The terminal monitors the downlink signal strength (such as Reference Signal Receiving Power (RSRP) or Signal-to-Noise Ratio (SNR)) of the currently serving satellite in real time. When the signal strength is detected to be below the preset threshold, it indicates that the quality of the current communication link is deteriorating and normal communication will soon be impossible, requiring a handover to be triggered as soon as possible. At this time, the terminal immediately triggers the reporting of visible satellite information, sending the latest set of visible satellites to the currently serving satellite to request the network side to initiate the handover process as soon as possible. This reporting method is event-triggered and is not constrained by the periodic reporting cycle, ensuring that the network side obtains the key information required for handover in a timely manner when the link quality deteriorates.

[0081] (3) Reporting is triggered in response to attitude changes of the mobile vehicle exceeding a preset threshold. The terminal monitors the attitude changes of the mobile vehicle in real time through attitude sensors. When the change in attitude angles (roll angle, pitch angle, yaw angle) exceeds the preset threshold, it indicates that the antenna orientation has changed significantly, the visible satellite set may have changed considerably, and the previously reported visible satellite information may no longer be accurate. At this time, the terminal immediately triggers re-reporting, sending the updated visible satellite set to the currently serving satellites to avoid the network side making incorrect switching decisions based on outdated information. For example, reporting can be triggered when the roll angle change rate is greater than 30° / second or the pitch angle change exceeds 5°. This attitude change threshold can be configured according to the specific platform characteristics and communication requirements.

[0082] (4) Reporting is triggered in response to receiving a reporting instruction from the currently serving satellite. After receiving a reporting instruction message sent by the currently serving satellite via downlink signaling, the terminal immediately performs visible satellite information reporting. This method enables the network side to proactively request the terminal to report the latest visible satellite information according to its own scheduling needs. For example, before the network side is preparing to initiate a handover decision, or when the network side detects a change in system status and needs to re-evaluate the handover candidate set, it sends a reporting instruction to the terminal to obtain the latest data.

[0083] The aforementioned reporting conditions can be used individually or in combination. For example, the terminal can use a combination of periodic reporting and signal strength triggering: under normal circumstances, it reports periodically every 5 seconds, and when the signal strength falls below a threshold, it triggers reporting immediately without periodicity. Another example is a combination of attitude change triggering and network indication triggering: the terminal actively reports when its attitude changes significantly, and also responds to active query requests from the network side. The terminal can flexibly adjust the combination of reporting conditions and corresponding parameter thresholds according to network configuration instructions.

[0084] Once the reporting condition is triggered, the terminal reports the visible satellite information, that is, it sends the visible satellite information, including the set of satellites visible to the antenna, to the currently serving satellite. If multiple reporting conditions are met simultaneously, the terminal only needs to perform one report and does not need to send it repeatedly.

[0085] In the above implementation process, by setting reporting conditions, the terminal can avoid unnecessary signaling overhead caused by frequent reporting, and report in a timely manner at critical moments to ensure the timeliness and reliability of handover.

[0086] In conjunction with the above embodiments, please refer to Figure 2 , Figure 2 A flowchart of another satellite handover method provided in this application embodiment, which is applied to a satellite base station, includes the following steps: Step S210: Obtain visible satellite information sent by the satellite communication terminal.

[0087] The visible satellite information includes the antenna visible satellite set, which is determined by the terminal according to the method provided in the above embodiments. That is, the antenna visible satellite set is the set of all antenna visible satellites obtained by the terminal after determining whether each candidate satellite falls within the beam scanning range of the phased array antenna based on the actual attitude information of its own phased array antenna, the ephemeris information of candidate satellites and its own position information.

[0088] In this embodiment, the satellite base station can refer to the currently serving satellite of the satellite communication terminal. After receiving the visible satellite information, the satellite base station parses it to extract the identification information of each satellite in the antenna's visible satellite set, as well as the auxiliary handover information that the terminal can optionally report (such as the azimuth information and signal quality information of each visible satellite). Through this information, the satellite base station learns all the candidate satellites that the terminal can currently communicate with, laying the foundation for subsequent handover target selection.

[0089] Step S220: Select a target satellite from the set of visible satellites according to a preset strategy and switch satellites.

[0090] Since all satellites in the visible satellite set have been determined by the terminal to be actually communicable, any satellite in the set can be a candidate for handover. The satellite base station then selects the optimal target satellite according to a preset strategy. This preset strategy can include any one or a combination of the following: a signal quality priority strategy, which selects the satellite with the best signal quality (e.g., highest RSRP or highest SNR) from the visible satellite set, suitable for scenarios where the terminal's current link quality is poor; a load balancing strategy, which selects the satellite with the lightest load after excluding satellites with loads exceeding a preset threshold, suitable for scenarios with high overall network load; a longest service time strategy, which calculates the remaining visible time of each visible satellite relative to the terminal based on ephemeris information and selects the longest, suitable for scenarios where it is desirable to reduce handover frequency; and a weighted comprehensive strategy, which performs a weighted score based on multiple dimensions such as signal quality, load rate, and service time, selecting the satellite with the highest comprehensive score. The satellite base station can flexibly select an applicable strategy or combination of strategies based on the current network status, auxiliary information reported by the terminal, and system operation strategies to choose the optimal target satellite for handover.

[0091] Step S230: Execute the handover process between the current serving satellite and the target switching satellite of the satellite communication terminal.

[0092] Specifically, during the handover process, the current serving satellite first sends a handover request message to the target handover satellite. This message contains the terminal's context information (such as terminal identifier, service type, and quality of service parameters). Upon receiving the handover request, the target handover satellite performs access control based on its resource availability, reserves corresponding communication resources, and returns a handover confirmation message to the current serving satellite. After receiving the handover confirmation, the current serving satellite sends a handover command to the terminal via downlink signaling. This command contains the target handover satellite's access parameters (such as frequency, time slot, beam ID, and random access preamble).

[0093] According to the access parameters in the handover command, the terminal establishes downlink synchronization with the target satellite and executes a random access procedure. After successful access, it sends a handover completion confirmation message to the target satellite. Upon receiving the confirmation message, the target satellite notifies the current serving satellite to release the original link resources. The current serving satellite then releases the communication link resources between itself and the terminal, ending the handover process. At this point, the terminal's communication link has been transferred from the original serving satellite to the target satellite, maintaining communication continuity. After handover, the terminal can report an updated set of visible satellites to the target satellite, preparing a candidate list of target satellites for subsequent handovers.

[0094] If an anomaly occurs during the handover process, such as the terminal being unable to access the target satellite, the satellite base station can activate a backup processing mechanism to reselect other satellites from the set of visible satellites and initiate a new handover attempt, or instruct the terminal to re-report the latest visible satellite information.

[0095] In the above implementation process, since the target switching satellite is selected from the set of visible satellites reported by the terminal, and this set is determined based on the actual attitude information of the terminal's phased array antenna, the terminal's antenna beam can effectively cover the direction of the target satellite during the switching process, and the switching success rate and link establishment reliability are fundamentally guaranteed.

[0096] Please refer to the above method embodiments. Figure 3 , Figure 3 This application provides a structural block diagram of a satellite switching device 300, which may be a module, program segment, or code on an electronic device (such as a satellite communication terminal). It should be understood that this device 300 corresponds to the method embodiments described above and is capable of executing the various steps involved in the method embodiments. The specific functions of this device 300 can be found in the description above; to avoid repetition, detailed descriptions are appropriately omitted here.

[0097] Optionally, the device 300 includes: The information acquisition module 310 is used to acquire the attitude information of the phased array antenna, the ephemeris information of each candidate satellite, and the location information of the satellite communication terminal; The visible satellite determination module 320 is used to determine the visibility of each candidate satellite relative to the beam scanning range of the phased array antenna based on the attitude information, the ephemeris information and the position information, so as to obtain the set of visible satellites of the antenna; The information transmission module 330 is used to send visible satellite information to the currently serving satellite, wherein the visible satellite information includes the set of visible satellites of the antenna, and the currently serving satellite is used to select a target switching satellite from the set of visible satellites of the antenna.

[0098] Optionally, the information acquisition module 310 is configured to calculate the position vector of each candidate satellite relative to the satellite communication terminal based on the ephemeris information and the position information; calculate the elevation angle and azimuth angle of each candidate satellite relative to the phased array antenna plane based on the attitude information and the position vector; and determine the set of visible satellites from each candidate satellite based on the elevation angle, the azimuth angle and the beam scanning range of the phased array antenna.

[0099] Optionally, the information acquisition module 310 is configured to add any candidate satellite to the antenna visible satellite set if the elevation angle is greater than or equal to a first threshold and the absolute value of the azimuth angle is less than or equal to a second threshold. The first threshold is determined based on the maximum scanning elevation angle in the beam scanning range, and the second threshold is determined based on the maximum scanning azimuth angle in the beam scanning range.

[0100] Optionally, the information acquisition module 310 is used to calculate the satellite position of each candidate satellite in the geocentric-geocentric coordinate system based on the ephemeris information; determine the terminal position of the satellite communication terminal in the geocentric-geocentric coordinate system based on the position information; calculate the position difference vector of each candidate satellite relative to the satellite communication terminal based on the satellite position and the terminal position; and convert the position difference vector to the navigation coordinate system of the satellite communication terminal through a coordinate transformation matrix to obtain the position vector.

[0101] Optionally, the information acquisition module 310 is used to transform the position vector from the navigation coordinate system to the array coordinate system to obtain the direction vector of each candidate satellite in the array coordinate system; for any candidate satellite, the elevation angle of the candidate satellite relative to the phased array antenna plane is calculated based on the ratio of the Z-axis component of the direction vector of the candidate satellite in the array coordinate system to the vector magnitude; and the azimuth angle of the candidate satellite relative to the phased array antenna plane is calculated based on the X-axis component and Y-axis component of the direction vector of the candidate satellite in the array coordinate system.

[0102] Optionally, the information acquisition module 310 is used to acquire the roll angle, pitch angle, and yaw angle output by the attitude sensor installed on the mobile carrier; acquire the installation azimuth angle and installation pitch angle of the phased array antenna on the mobile carrier; construct a coordinate rotation matrix of the array coordinate system relative to the navigation coordinate system based on the roll angle, the pitch angle, the yaw angle, the installation azimuth angle, and the installation pitch angle; and acquire the normal direction vector of the phased array antenna based on the coordinate rotation matrix, wherein the attitude information includes the normal direction vector.

[0103] Optionally, the visible satellite information includes the identification information of each visible satellite in the antenna's visible satellite set and auxiliary switching information. The auxiliary switching information includes at least one of the following: the azimuth information of each visible satellite relative to the phased array antenna and the signal quality information of each visible satellite.

[0104] Optionally, the information sending module 330 is used to send visible satellite information to the currently serving satellite when it is determined that the reporting conditions are met; The reporting conditions include at least one of the following: Periodically trigger reporting; A report is triggered in response to the signal strength of the currently serving satellite falling below a preset threshold. A report is triggered in response to the change in the attitude of the mobile carrier exceeding a preset threshold; Reporting is triggered in response to receiving a reporting instruction from the currently serving satellite.

[0105] This application also provides another satellite switching device, which may be a module, program segment, or code on an electronic device (such as a satellite base station). It should be understood that this device corresponds to the method embodiments described above and is capable of performing the various steps involved in the method embodiments. The specific functions of this device can be found in the description above, and detailed descriptions are appropriately omitted here to avoid repetition.

[0106] Optionally, the device includes: The information acquisition module is used to acquire visible satellite information sent by the satellite communication terminal. The visible satellite information includes a set of visible satellites visible to the antenna, which is determined by the satellite communication terminal according to the above method. The satellite selection module is used to select a target satellite from the set of satellites visible to the antenna according to a preset strategy; The satellite switching module is used to execute the switching process between the current serving satellite of the satellite communication terminal and the target switching satellite.

[0107] It should be noted that those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0108] Please refer to Figure 4 , Figure 4 This is a schematic diagram of an electronic device for performing a satellite handover method, provided in an embodiment of this application. The electronic device may include: at least one processor 410, such as a CPU; at least one communication interface 420; at least one memory 430; and at least one communication bus 440. The communication bus 440 is used to establish communication between these components. In this embodiment, the communication interface 420 is used for signaling or data communication with other node devices. The memory 430 may be a high-speed RAM or a non-volatile memory, such as at least one disk storage device. Optionally, the memory 430 may also be at least one storage device located remotely from the aforementioned processor. The memory 430 stores computer-readable instructions, which, when executed by the processor 410, cause the electronic device to perform the aforementioned method process.

[0109] Understandable. Figure 4 The structure shown is for illustrative purposes only; the electronic device may also include components that are more advanced than those shown. Figure 4 The more or fewer components shown, or having the same Figure 4 The different configurations shown. Figure 4 The components shown can be implemented using hardware, software, or a combination thereof.

[0110] This application provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it performs the method process executed by the electronic device in the above method embodiments.

[0111] This embodiment discloses a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions, and when the program instructions are executed by a computer, the computer can perform the methods provided in the above-described method embodiments.

[0112] In summary, the embodiments of this application provide a satellite handover method, electronic device, storage medium, and program product. The terminal autonomously acquires the actual attitude information of the phased array antenna and, based on this attitude information combined with ephemeris and position information, determines the visibility of each candidate satellite relative to the antenna beam scanning range. This yields a set of satellites actually visible to the antenna and reports it to the network side. This ensures that the network side's handover decision is based on the terminal's actual communication capabilities rather than traditional geometric visibility assumptions. This effectively eliminates the mismatch between geometric visibility and antenna visibility caused by the phased array antenna's non-horizontal installation and continuous attitude changes such as roll, pitch, and yaw during carrier movement. It also avoids the network side selecting satellites that the terminal cannot communicate with as handover targets, effectively improving the handover success rate.

[0113] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0114] Furthermore, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0115] Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0116] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0117] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A satellite handover method, characterized in that, Applied to a satellite communication terminal, wherein the phased array antenna of the satellite communication terminal is mounted on the surface of a mobile carrier, the method includes: Acquire the attitude information of the phased array antenna, the ephemeris information of each candidate satellite, and the location information of the satellite communication terminal; Based on the attitude information, the ephemeris information, and the position information, the visibility of each candidate satellite relative to the beam scanning range of the phased array antenna is determined, and the set of satellites visible to the antenna is obtained. Send visible satellite information to the currently serving satellite, wherein the visible satellite information includes the set of visible satellites of the antenna, and the currently serving satellite is used to select a target switching satellite from the set of visible satellites of the antenna.

2. The method according to claim 1, characterized in that, The step of determining the visibility of each candidate satellite relative to the beam scanning range of the phased array antenna based on the attitude information, the ephemeris information, and the position information, to obtain the set of satellites visible to the antenna, includes: Based on the ephemeris information and the position information, calculate the position vector of each candidate satellite relative to the satellite communication terminal; Based on the attitude information and the position vector, calculate the elevation angle and azimuth angle of each candidate satellite relative to the phased array antenna plane; Based on the elevation angle, the azimuth angle, and the beam scanning range of the phased array antenna, the set of visible satellites is determined from each candidate satellite.

3. The method according to claim 2, characterized in that, The step of determining the set of visible satellites from each candidate satellite based on the elevation angle, the azimuth angle, and the beam scanning range of the phased array antenna includes: For any candidate satellite, if the elevation angle is greater than or equal to a first threshold and the absolute value of the azimuth angle is less than or equal to a second threshold, then the candidate satellite is added to the set of visible satellites of the antenna. The first threshold is determined based on the maximum scanning elevation angle in the beam scanning range, and the second threshold is determined based on the maximum scanning azimuth angle in the beam scanning range.

4. The method according to claim 2, characterized in that, The step of calculating the position vector of each candidate satellite relative to the satellite communication terminal based on the ephemeris information and the position information includes: Calculate the satellite position of each candidate satellite in the geocentric-geo-fixed coordinate system based on the ephemeris information; The location of the satellite communication terminal in the geocentric-ground-fixed coordinate system is determined based on the location information. Calculate the position difference vector of each candidate satellite relative to the satellite communication terminal based on the satellite position and the terminal position; The position difference vector is transformed to the navigation coordinate system of the satellite communication terminal using a coordinate transformation matrix to obtain the position vector.

5. The method according to claim 2, characterized in that, The step of calculating the elevation and azimuth angles of each candidate satellite relative to the phased array antenna plane based on the attitude information and the position vector includes: The position vector is transformed from the navigation coordinate system to the array coordinate system to obtain the direction vector of each candidate satellite in the array coordinate system; For any candidate satellite, the elevation angle of the candidate satellite relative to the phased array antenna plane is calculated based on the ratio of the Z-axis component of the direction vector of the candidate satellite in the array coordinate system to the vector magnitude. Based on the X-axis and Y-axis components of the direction vector of the candidate satellite in the array coordinate system, the azimuth angle of the candidate satellite relative to the phased array antenna plane is calculated.

6. The method according to claim 1, characterized in that, Obtaining the attitude information of the phased array antenna includes: The roll angle, pitch angle, and yaw angle output by the attitude sensors installed on the mobile carrier are obtained. Obtain the installation azimuth and elevation angles of the phased array antenna on the mobile carrier; Based on the roll angle, pitch angle, yaw angle, installation azimuth angle, and installation pitch angle, construct the coordinate rotation matrix of the array coordinate system relative to the navigation coordinate system; The normal direction vector of the phased array antenna is obtained based on the coordinate rotation matrix, and the attitude information includes the normal direction vector.

7. The method according to claim 1, characterized in that, The visible satellite information includes the identification information of each visible satellite in the antenna visible satellite set and auxiliary switching information. The auxiliary switching information includes at least one of the following: the azimuth information of each visible satellite relative to the phased array antenna and the signal quality information of each visible satellite.

8. The method according to claim 1, characterized in that, Sending visible satellite information to the currently serving satellite includes: When it is determined that the reporting conditions are met, visible satellite information is sent to the currently serving satellite; The reporting conditions include at least one of the following: Periodically trigger reporting; A report is triggered in response to the signal strength of the currently serving satellite falling below a preset threshold. A report is triggered in response to the change in the attitude of the mobile carrier exceeding a preset threshold; Reporting is triggered in response to receiving a reporting instruction from the currently serving satellite.

9. A satellite handover method, characterized in that, Applied to satellite base stations, the method includes: Acquire visible satellite information sent by a satellite communication terminal, wherein the visible satellite information includes a set of visible satellites visible to the antenna, and the set of visible satellites visible to the antenna is determined by the satellite communication terminal according to any one of claims 1-8; Target switching satellites are selected from the set of visible satellites according to a preset strategy; The process of switching between the current serving satellite and the target switching satellite of the satellite communication terminal is executed.

10. An electronic device, characterized in that, It includes a processor and a memory, the memory storing computer-readable instructions that, when executed by the processor, perform the method as described in any one of claims 1-9.

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 performs the method as described in any one of claims 1-9.

12. A computer program product, characterized in that, It includes computer program instructions, which, when read and executed by a processor, perform the method as described in any one of claims 1-9.

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