Terminal satellite alignment method

Abstract

The invention discloses a satellite alignment method for a terminal. The method comprises the steps that a built-in ephemeris of a terminal, calibration initial time of the terminal and a satellite and a target moment when the terminal is connected to the satellite are acquired, and the built-in ephemeris comprises operation state parameters used for representing that the satellite is in a satellite orbit; determining a first coordinate of the satellite in an orbital coordinate system according to the operation state parameter, the calibration initial time and the target moment; the first coordinate of the satellite in the orbital coordinate system is converted into a second coordinate in a station center sphere coordinate system, and the sphere center in the station center sphere coordinate system is a terminal; and determining relative position information between the terminal and the satellite according to the second coordinate, and adjusting the terminal according to the relative position information. According to the method and the device, the technical problems of long connection time and low efficiency caused by blind search when the handheld terminal initially accesses the satellite are solved.

Description

Technical Field

[0001] This application relates to the field of communications, and more specifically, to a terminal satellite alignment method. Background Technology

[0002] Current methods for aligning handheld terminals with satellite beams rely on measuring the received satellite signal strength during the initial blind search. This involves the handheld terminal repeatedly trying different angles to align with unseen satellites in the sky. Once the received signal strength reaches a threshold, the handheld terminal is considered properly aligned. This blind search method is inefficient, requiring repeated signal strength measurements to determine alignment, resulting in long connection times—potentially a minute or more.

[0003] There is currently no effective solution to the above problems. Summary of the Invention

[0004] This application provides a terminal satellite connection method to at least solve the technical problem of long connection time and low efficiency caused by blind search when a handheld terminal initially connects to a satellite.

[0005] According to one aspect of the embodiments of this application, a terminal satellite alignment method is provided, comprising: acquiring the terminal's built-in ephemeris, the initial calibration time between the terminal and the satellite, and the target time for the terminal to access the satellite, wherein the built-in ephemeris includes parameters for representing the satellite's operational status in its orbit; determining a first coordinate of the satellite in an orbital coordinate system based on the operational status parameters, the initial calibration time, and the target time; transforming the first coordinate of the satellite in the orbital coordinate system to a second coordinate in a station-centered spherical coordinate system, wherein the center of the sphere in the station-centered spherical coordinate system is the terminal; determining the relative position information between the terminal and the satellite based on the second coordinate, and adjusting the terminal based on the relative position information.

[0006] Optionally, the operational status parameters include: the six roots of the satellite orbit; based on the operational status parameters, the initial calibration time, and the target time, determining the first coordinate of the satellite in the orbital coordinate system, including: determining the average angular velocity of the satellite; based on the average angular velocity, the initial calibration time, and the target time, determining the mean anomaly angle of the satellite at the target time; obtaining the eccentricity in the six roots of the satellite orbit, and solving Kepler's equations based on the eccentricity and the mean anomaly angle to obtain the off-anomaly angle; obtaining the semi-major axis of the elliptical orbit in the six roots of the satellite orbit, and determining the first distance between the satellite and the Earth's center based on the semi-major axis, eccentricity, and off-anomaly angle; determining the true anomaly angle based on the eccentricity and the off-anomaly angle; and determining the first coordinate of the satellite in the orbital coordinate system based on the first distance and the true anomaly angle.

[0007] Optionally, the average angular velocity of the satellite is determined by: obtaining the gravitational constant, Earth's mass, and semi-major axis; and determining the average angular velocity of the satellite based on the gravitational constant, Earth's mass, and semi-major axis.

[0008] Optionally, transforming the satellite's first coordinate in the orbital coordinate system to a second coordinate in the station-centered spherical coordinate system includes: transforming the satellite's first coordinate in the orbital coordinate system to a third coordinate in the geocentric inertial coordinate system; transforming the satellite's third coordinate in the geocentric inertial coordinate system to a fourth coordinate in the geocentric Earth-fixed coordinate system; transforming the satellite's fourth coordinate in the geocentric Earth-fixed coordinate system to a fifth coordinate in the station-centered rectangular coordinate system, wherein the origin of the station-centered rectangular coordinate system is the terminal point; and transforming the satellite's fifth coordinate in the station-centered rectangular coordinate system to a second coordinate in the station-centered spherical coordinate system.

[0009] Optionally, the first coordinate of the satellite in the orbital coordinate system is transformed to the third coordinate in the geocentric inertial coordinate system, including: obtaining the longitude of the satellite's ascending node, the satellite's orbital inclination, and the argument of its pericentric point from the operational status parameters; determining the first matrix, the second matrix, and the third matrix based on the longitude of the satellite's ascending node, the satellite's orbital inclination, and the argument of its pericentric point, respectively; and transforming the first coordinate based on the first matrix, the second matrix, and the third matrix to obtain the third coordinate.

[0010] Optionally, the third coordinate of the satellite in the geocentric inertial coordinate system is transformed to the fourth coordinate in the geocentric geofixed coordinate system, including: obtaining the Earth's rotation angular velocity and the Julian time of the target time; determining the fourth matrix based on the Earth's rotation angular velocity and the Julian time of the target time; and transforming the third coordinate based on the fourth matrix to obtain the fourth coordinate.

[0011] Optionally, the fourth coordinate of the satellite in the geocentric coordinate system can be transformed to the fifth coordinate in the station-centered rectangular coordinate system, including: obtaining the Earth's radius, the longitude and latitude of the terminal; determining the station-centered coordinates corresponding to the terminal based on the Earth's radius, the longitude and latitude of the terminal; determining the fifth matrix based on the longitude and latitude of the terminal; and transforming the fourth coordinate based on the fifth matrix and the station-centered coordinate to obtain the fifth coordinate.

[0012] Optionally, the fifth coordinate of the satellite in the station-centered rectangular coordinate system is transformed to the second coordinate in the station-centered spherical coordinate system, including: obtaining the X-axis coordinate, Y-axis coordinate and Z-axis coordinate in the fifth coordinate; determining the radial distance based on the X-axis coordinate, Y-axis coordinate and Z-axis coordinate; determining the first angle based on the Z-axis coordinate and radial distance, and determining the second angle based on the Y-axis coordinate and X-axis coordinate; and determining the second coordinate based on the radial distance, the first angle and the second angle.

[0013] Optionally, determining the relative position information between the terminal and the satellite based on the second coordinates includes: obtaining a first angle in the second coordinates; determining the elevation angle between the terminal and the satellite based on the difference between the right angle and the first angle; determining the second angle as the azimuth angle between the terminal and the satellite when the X-axis coordinate in the fifth coordinates is greater than 0, and determining the sum of the second angle and the angle as the azimuth angle between the terminal and the satellite when the X-axis coordinate in the fifth coordinates is less than 0; and determining the relative position information based on the elevation angle and the azimuth angle.

[0014] Optionally, after adjusting the terminal based on the relative position information, the method further includes: acquiring a first signal sent by the terminal to the satellite; receiving a second signal sent by the satellite to the terminal based on the first signal, wherein the second signal contains updated information of the operating status parameters; and stopping the updating of the operating status parameters if the difference between the updated information and the original information of the operating status parameters is less than a preset threshold.

[0015] Optionally, the method further includes: when the terminal is placed horizontally and is in communication with the satellite, obtaining the Received Signal Strength Indication (RSSI) corresponding to the downlink signals received by the satellite simultaneously by the two antennas in the terminal, to obtain the left antenna RSSI and the right antenna RSSI; comparing the left antenna RSSI and the right antenna RSSI, and controlling the terminal to rotate towards the antenna with the larger RSSI value, until the difference between the left antenna RSSI and the right antenna RSSI is less than a first threshold; when the terminal is placed vertically, obtaining the Received Signal Strength Indication (RSSI) corresponding to the downlink signals received by the satellite simultaneously by the two antennas in the terminal, to obtain the upper antenna RSSI and the lower antenna RSSI; comparing the upper antenna RSSI and the lower antenna RSSI, and controlling the terminal to rotate towards the antenna with the larger RSSI value, until the difference between the upper antenna RSSI and the lower antenna RSSI is less than a second threshold.

[0016] In this embodiment, by acquiring the terminal's built-in ephemeris, the initial calibration time between the terminal and the satellite, and the target time for the terminal to connect to the satellite, wherein the built-in ephemeris includes parameters representing the satellite's operational status in its orbit; based on the operational status parameters, the initial calibration time, and the target time, the first coordinate of the satellite in the orbital coordinate system is determined; the first coordinate of the satellite in the orbital coordinate system is transformed to a second coordinate in a station-centered spherical coordinate system, wherein the center of the sphere in the station-centered spherical coordinate system is the terminal; the relative position information between the terminal and the satellite is determined based on the second coordinate, and the terminal is adjusted based on the relative position information, thereby achieving the goal of improving the initial docking speed between the terminal and the satellite, thus realizing the technical effect of reducing search time and improving efficiency, and thus solving the technical problem of long connection time and low efficiency caused by blind search when a handheld terminal initially connects to a satellite. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0018] Figure 1 This is a hardware structure block diagram of a computer terminal for implementing a terminal satellite connection method according to an embodiment of this application;

[0019] Figure 2 This is a flowchart of a terminal satellite alignment method according to an embodiment of this application;

[0020] Figure 3 This is a schematic diagram of a transformation from an orbital coordinate system to a geocentric inertial coordinate system according to an embodiment of this application;

[0021] Figure 4 This is a schematic diagram of a transformation from a geocentric inertial coordinate system to a geocentric geofixed coordinate system according to an embodiment of this application;

[0022] Figure 5 This is a schematic diagram of a geocentric coordinate system with a fixed coordinate system according to an embodiment of this application.

[0023] Figure 6 This is a schematic diagram of a dual-antenna RSSI tracking process according to an embodiment of this application;

[0024] Figure 7 This is a schematic diagram of a dual-antenna RSSI tracking principle according to an embodiment of this application;

[0025] Figure 8 This is a schematic flowchart of a satellite beam alignment method based on built-in ephemeris and signal tracking according to an embodiment of this application;

[0026] Figure 9 This is a structural diagram of a terminal satellite tracking device according to an embodiment of this application. Detailed Implementation

[0027] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0028] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0029] First, some nouns or terms that appear in the explanation of the embodiments of this application shall be interpreted as follows:

[0030] The six orbital elements: six parameters necessary to determine the orbit of a celestial body or spacecraft in its Keplerian orbit, including: semi-major axis (a), eccentricity (e), orbital inclination (i), pericentric argument (ω), ascending node longitude (Ω), and true anomaly. .

[0031] Geocentric Inertial Frame (ECI): An inertial coordinate system with the Earth's center of mass as its origin, whose coordinate axes do not rotate with the Earth's rotation. X-axis: Points to the vernal equinox, the intersection of the ecliptic plane and the celestial equator. The vernal equinox is located on the celestial sphere as the Sun crosses the equator from south to north along the ecliptic. Y-axis: Perpendicular to the X-axis, located within the celestial equator plane, and points in the same direction as the Earth's rotation. Z-axis: Perpendicular to both the X and Y axes, pointing towards the Earth's North Pole, i.e., parallel to the Earth's rotation axis.

[0032] Geocentric-Flat (ECEF) coordinate system: A geocentric coordinate system with the Earth's center of mass as its origin. The system rotates with the Earth, so the coordinates of points on the Earth's surface are fixed in this system. X-axis: points to the intersection of the Greenwich Meridian and the equator; Z-axis: coincides with the Earth's axis of rotation and points to the North Pole; Y-axis: perpendicular to the XOZ plane, forming a right-handed coordinate system with the X-axis and Z-axis.

[0033] Station-centered rectangular coordinate system: A local coordinate system with the ground observation station (station) as its origin, commonly used to describe the position of an observed target (such as a satellite or celestial body) relative to the observation station. X-axis: Points to the intersection of the meridian plane and the horizon at the station's location, usually pointing due north; Y-axis: Perpendicular to the ground plane, pointing towards the zenith; Z-axis: Perpendicular to the XOY plane, located on the ground plane, forming a right-handed coordinate system with the X and Y axes, pointing due east.

[0034] Received Signal Strength Indicator (RSSI): Used to measure the strength of wireless signals. It is calculated based on the signal power received by the wireless device. The device converts the received signal strength into a value in dBw or dBm and displays it.

[0035] GNSS (Global Navigation Satellite System) is a space infrastructure that uses multiple satellites to provide users with continuous, real-time positioning, navigation, and timing services. GNSS systems transmit radio signals to receivers on the Earth's surface, which then measure the arrival time of these signals to calculate precise geographical location, speed, and time information.

[0036] LOS (Line-of-Sight): In the fields of communications engineering and wireless signal transmission, LOS usually refers to "line-of-sight path" or "line-of-sight propagation." It describes the propagation method of a wireless signal that can travel directly from the transmitting point to the receiving point without encountering any obstacles.

[0037] Among related technologies, there are two main approaches to aligning a handheld terminal with a satellite beam. One approach involves an initial blind search by the handheld terminal, which requires measuring the strength of the received satellite signal to align itself. Specifically, the handheld terminal continuously tries to switch angles to align with satellites that are not visible in the sky. Once the received signal strength reaches a threshold, the handheld terminal is considered to be aligned. The other approach involves the terminal connecting to the network, where the satellite broadcasts its position data to the handheld terminal. The handheld terminal then calculates the azimuth and elevation angles between itself and the satellite based on its own GNSS data and adjusts the antenna angle accordingly.

[0038] Of the two methods described above, the terminal blind search method is less efficient, requiring repeated signal strength measurements to determine if the direction is aligned with the satellite, resulting in a longer connection time, potentially a minute or even longer. The terminal alignment method using satellite position information requires the terminal to be already associated with the target satellite, receiving and calculating the initial satellite position information via the downlink. If the terminal is not connected to a satellite or the channel quality is poor, signal demodulation cannot be achieved.

[0039] To address the problems existing in related technologies, this application provides a terminal satellite alignment method, which can be run in... Figure 1 The computer terminal shown is described below.

[0040] The terminal satellite alignment method embodiments provided in this application can be executed in mobile terminals, computer terminals, or similar computing devices. Figure 1 A hardware block diagram of a computer terminal for implementing a terminal-to-star method is shown. Figure 1As shown, the computer terminal 10 may include one or more processors (shown as 102a, 102b, ..., 102n in the figure) (the processor may include, but is not limited to, a microprocessor MCU or a programmable logic device FPGA, etc.), a memory 104 for storing data, and a transmission module 106 for communication functions connected via wired and / or wireless networks. In addition, it may also include: a display, a keyboard, a cursor control device, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of the I / O interface), a network interface, and a BUS bus. Those skilled in the art will understand that... Figure 1 The structure shown is for illustrative purposes only and does not limit the structure of the aforementioned electronic device. For example, computer terminal 10 may also include... Figure 1 The more or fewer components shown, or having the same Figure 1 The different configurations shown.

[0041] It should be noted that the aforementioned one or more processors and / or other data processing circuits are generally referred to herein as "data processing circuits". These data processing circuits may be embodied, in whole or in part, in software, hardware, firmware, or any other combination thereof. Furthermore, the data processing circuits may be a single, independent processing module, or may be integrated, in whole or in part, into any other element within the computer terminal 10. As involved in the embodiments of this application, the data processing circuits serve as a processor control mechanism (e.g., selection of a variable resistor termination path connected to an interface).

[0042] The memory 104 can be used to store software programs and modules of application software, such as the program instructions / data storage device corresponding to the terminal satellite alignment method in this embodiment. The processor executes various functional applications and data processing by running the software programs and modules stored in the memory 104, thereby implementing the aforementioned terminal satellite alignment method. The memory 104 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include memory remotely located relative to the processor, and these remote memories can be connected to the computer terminal 10 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0043] The transmission module 106 is used to receive or send data via a network. Specific examples of the network described above may include a wireless network provided by the communication provider of the computer terminal 10. In one example, the transmission module 106 includes a network interface controller (NIC), which can connect to other network devices via a base station to communicate with the Internet. In another example, the transmission module 106 may be a radio frequency (RF) module, used for wireless communication with the Internet.

[0044] The display can be, for example, a touchscreen liquid crystal display (LCD) that allows the user to interact with the user interface of the computer terminal 10.

[0045] It should be noted here that, in some optional embodiments, the above... Figure 1 The computer terminal shown may include hardware components (including circuitry), software components (including computer code stored on a computer-readable medium), or a combination of both hardware and software components. It should be noted that... Figure 1 This is only one instance of a specific particular instance, and is intended to illustrate the types of components that may exist in the aforementioned computer terminal.

[0046] In the above operating environment, this application provides a terminal satellite connection method embodiment. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Also, although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than that shown here.

[0047] Figure 2 This is a flowchart of a terminal satellite alignment method according to an embodiment of this application, such as... Figure 2 As shown, the method includes the following steps:

[0048] Step S202: Obtain the terminal's built-in ephemeris, the initial calibration time between the terminal and the satellite, and the target time for the terminal to access the satellite. The built-in ephemeris includes parameters representing the satellite's operational status in its orbit.

[0049] In step S202 above, the built-in ephemeris is satellite orbital parameter data pre-stored inside the (handheld) terminal, including the aforementioned operational status parameters, such as the semi-major axis of the elliptical orbit. eccentricity Track inclination Argument of the pericentric point Longitude of ascending node and true near point angle These parameters describe the satellite's motion and position in its orbit. Built-in ephemeris data is typically used by handheld terminals for preliminary satellite positioning without prior communication with the satellite. Since handheld terminals may not receive the latest ephemeris data from the satellite in real time, built-in ephemeris data provides a preliminary position prediction before the terminal establishes contact with the satellite. However, built-in ephemeris data often becomes inaccurate over time because the orbital parameters it is based on may have changed due to various factors such as minor variations in Earth's gravity and solar wind. Therefore, built-in ephemeris data is considered a coarse position prediction.

[0050] Calibration initial time This refers to the starting time point used by the terminal to calculate the satellite's position. Since satellite orbital parameters (such as mean anomaly) change over time, the real-time position calculation of the satellite needs to be based on this initial calibration time. Target time. This refers to the point in time when the handheld terminal intends or needs to establish communication with a satellite. It is set when the handheld terminal begins the satellite search and alignment process, and is used to calculate the satellite's expected position at that moment. The target time can also be called the current time. Using the target time, the handheld terminal can calculate the satellite's orbital coordinates at that moment based on its built-in ephemeris data, thereby guiding the terminal's antenna adjustment to align with the satellite beam.

[0051] Step S204: Determine the first coordinate of the satellite in the orbital coordinate system based on the operating status parameters, calibration initial time, and target time.

[0052] In step S204 above, by combining the operating status parameters, calibration initial time and target time in the built-in ephemeris, the handheld terminal can calculate the coordinates of the satellite relative to the orbital coordinate system at the target time, i.e. the first coordinates mentioned above, through the mathematical model of orbital dynamics, without real-time ephemeris updates.

[0053] Step S206: Transform the first coordinate of the satellite in the orbital coordinate system to the second coordinate in the station-centered spherical coordinate system, where the center of the sphere in the station-centered spherical coordinate system is the terminal.

[0054] In step S206 above, the transformation from the orbital coordinate system to the station-centered sphere coordinate system involves multiple coordinate system transformations. Starting from the satellite's coordinates in the orbital coordinate system, the transformation is gradually made to the station-centered sphere coordinate system centered on the handheld terminal's position, thereby determining the satellite's coordinates in the station-centered sphere coordinate system, i.e., the second coordinates.

[0055] Step S208: Determine the relative position information between the terminal and the satellite based on the second coordinates, and adjust the terminal based on the relative position information.

[0056] In step S208 above, the relative position information includes azimuth and elevation. The azimuth describes the angular distance of the satellite on the horizontal plane relative to true north, while the elevation is the altitude angle of the satellite relative to the horizon where the handheld terminal is located. The relative position information is determined by the second coordinate. Based on the obtained relative position information (i.e., azimuth and elevation), the handheld terminal adjusts its orientation so that the antenna inside the terminal is aligned with the satellite.

[0057] Through steps S202 to S208, the expected position of the satellite is initially determined, thereby accelerating the satellite search process and achieving satellite alignment in the initial stage of establishing communication with the satellite. This achieves the goal of improving the initial docking speed between the terminal and the satellite, thus realizing the technical effects of reducing search time and improving efficiency. It also solves the technical problem of long connection times and low efficiency caused by blind searching when handheld terminals initially connect to satellites. The following is a further explanation.

[0058] In the aforementioned terminal-based satellite alignment method, the operational status parameters include: the six orbital roots of the satellite; based on the operational status parameters, the initial calibration time, and the target time, determining the satellite's first coordinates in the orbital coordinate system includes: determining the satellite's average angular velocity; determining the satellite's mean anomaly at the target time based on the average angular velocity, the initial calibration time, and the target time; obtaining the eccentricity from the six orbital roots, and solving Kepler's equations based on the eccentricity and the mean anomaly to obtain the off-anomaly angle; obtaining the semi-major axis of the elliptical orbit from the six orbital roots, and determining the first distance between the satellite and the Earth's center based on the semi-major axis, eccentricity, and off-anomaly angle; determining the true anomaly angle based on the eccentricity and the off-anomaly angle; and determining the satellite's first coordinates in the orbital coordinate system based on the first distance and the true anomaly angle.

[0059] In the above steps, determining the satellite's average angular velocity includes: obtaining the gravitational constant, Earth's mass, and semi-major axis; and determining the satellite's average angular velocity based on the gravitational constant, Earth's mass, and semi-major axis.

[0060] In some embodiments of this application, an orbital coordinate system is established, with the origin located at the Earth's center, the X and Y axes located in the orbital plane, and the Z axis coinciding with the orbital plane normal vector. Determining the satellite's first coordinates in the orbital coordinate system specifically includes the following process:

[0061] (1) Determine the satellite's position at the target time. The angle of the near point :

[0062]

[0063] in, To calibrate the initial time, The average angular velocity of the satellite is expressed in rad / s. The calculation formula is as follows:

[0064]

[0065] in, The semi-major axis represents the elliptical orbit, while the radius represents the circular orbit. The gravitational constant, For Earth mass, .

[0066] (2) Calculate the angle of near point :

[0067] By solving the Kepler equations ,in, Eccentricity This represents the angle of approach. For a circular orbit, it is easy to obtain... .

[0068] (3) Calculate the first distance r from the satellite to the Earth's center:

[0069]

[0070] For a circular orbit .

[0071] (4) Calculate the true anterior angle :

[0072]

[0073] if , .

[0074] (5) Calculate the satellite's first coordinate in the orbital coordinate system:

[0075]

[0076] The first coordinate is the fundamental coordinate for coordinate transformations in all reference frames. By transforming the obtained coordinates using the transformation matrices for different reference frames, the satellite's coordinates in different reference frames can be obtained. When the terminal is not connected to a network, it is generally considered that the terminal cannot accurately obtain satellite coordinate parameters.

[0077] In step S206 of the above-mentioned terminal satellite alignment method, transforming the first coordinate of the satellite in the orbital coordinate system to the second coordinate in the station-centered spherical coordinate system includes: transforming the first coordinate of the satellite in the orbital coordinate system to the third coordinate in the geocentric inertial coordinate system; transforming the third coordinate of the satellite in the geocentric inertial coordinate system to the fourth coordinate in the geocentric geo-fixed coordinate system; transforming the fourth coordinate of the satellite in the geocentric geo-fixed coordinate system to the fifth coordinate in the station-centered rectangular coordinate system, wherein the origin of the station-centered rectangular coordinate system is the terminal; and transforming the fifth coordinate of the satellite in the station-centered rectangular coordinate system to the second coordinate in the station-centered spherical coordinate system.

[0078] In the above steps, the first coordinate of the satellite in the orbital coordinate system is transformed to the third coordinate in the geocentric inertial coordinate system, including: obtaining the longitude of the satellite's ascending node, the satellite's orbital inclination, and the argument of the pericentric point from the operational status parameters; determining the first matrix, the second matrix, and the third matrix based on the longitude of the satellite's ascending node, the satellite's orbital inclination, and the argument of the pericentric point, respectively; and transforming the first coordinate based on the first matrix, the second matrix, and the third matrix to obtain the third coordinate.

[0079] In some embodiments of this application, when transforming the satellite's first coordinates in the orbital coordinate system to the third coordinates in the geocentric inertial coordinate system, without considering the Greenwich Mean Time (GMT) sidereal hour, the orbital coordinate system can be transformed into a central celestial inertial frame through a three-fold direction cosine matrix transformation. The following is combined with... Figure 3 To explain, Figure 3 This is a schematic diagram of a transformation from an orbital coordinate system to a geocentric inertial coordinate system according to an embodiment of this application, as shown below. Figure 3 As shown, during the first transformation, the orbital plane (i.e., the plane of the orbital coordinate system on the XOY axis) rotates around the z-axis of the reference coordinate system (i.e., the geocentric inertial coordinate system). ,in, This is the longitude of the satellite's ascending node, at which point the ascending node coincides with the x-axis of the reference coordinate system; during the second transformation, the orbital plane rotates around the x-axis of the reference coordinate system. ,in, The orbital inclination is the angle at which the positive normal of the orbital plane coincides with the z-axis of the reference coordinate system; during the third transformation, the orbital plane rotates around the z-axis of the reference coordinate system by... ,in, The argument of the pericentric point is where the eccentricity vector coincides with the x-axis of the reference coordinate system. Figure 3 In the diagram, v represents the velocity of the motion, and h represents the ascending axis.

[0080] The specific calculations are as follows:

[0081]

[0082] in:

[0083]

[0084]

[0085]

[0086] in, Describes the first matrix. Represents the second matrix, Represents the third matrix. Indicates the first coordinate. This represents the third coordinate.

[0087] In the above steps, the third coordinate of the satellite in the geocentric inertial coordinate system is transformed to the fourth coordinate in the geocentric geofixed coordinate system, including: obtaining the Earth's rotation angular velocity and the Julian time of the target time; determining the fourth matrix based on the Earth's rotation angular velocity and the Julian time of the target time; and transforming the third coordinate based on the fourth matrix to obtain the fourth coordinate.

[0088] In some embodiments of this application, the origins of the geocentric inertial coordinate system and the geocentric Earth-fixed coordinate system coincide, and there is a relative rotation between the two. The angular velocity points to the Z-axis and rotates from west to east. The Earth's rotation angular velocity is... for rad / s. The following is combined with... Figure 4 To explain, Figure 4 This is a schematic diagram of a transformation from a geocentric inertial coordinate system to a geocentric Earth-fixed coordinate system according to an embodiment of this application. Specifically, the formula for transforming the third coordinate of a satellite in the geocentric inertial coordinate system to the fourth coordinate in the geocentric Earth-fixed coordinate system is as follows:

[0089]

[0090] in, Indicates the fourth coordinate. Julian time indicating the target time This represents the fourth matrix.

[0091] In the above steps, the fourth coordinate of the satellite in the geocentric coordinate system is transformed into the fifth coordinate in the station-centered rectangular coordinate system. This includes: obtaining the Earth's radius, the longitude and latitude of the terminal; determining the station-centered coordinates corresponding to the terminal based on the Earth's radius, the longitude and latitude of the terminal; determining the fifth matrix based on the longitude and latitude of the terminal; and transforming the fourth coordinates based on the fifth matrix and the station-centered coordinates to obtain the fifth coordinates.

[0092] In some embodiments of this application, the station-centered rectangular coordinate system is also called the North-Sky-East coordinate system. The station-centered rectangular coordinate system is defined as follows: the X-axis points north; the Y-axis points to the zenith; and the Z-axis points east. The coordinates of the station center (i.e., the coordinates corresponding to the terminal) are usually represented using a latitude-longitude coordinate system. For ease of calculation, in the embodiments of this application, the influence of the Earth's surface is ignored, and only latitude and longitude are considered. It is assumed that the longitude of the station center (i.e., the terminal) is... Latitude is , Given that the Earth's radius is 6378 km, and considering the Earth as an ideal sphere in this embodiment, the formula for calculating the coordinates of the station center is as follows:

[0093]

[0094] The formula for calculating the satellite's coordinates in the station-centered rectangular coordinate system is as follows:

[0095]

[0096] in, Indicates the fifth coordinate. Represents the fifth matrix. This represents the coordinates of the station center. A schematic diagram showing the conversion from the geocentric coordinate system to the station center rectangular coordinate system is shown below. Figure 5 As shown.

[0097] In the above steps, the fifth coordinate of the satellite in the station-centered rectangular coordinate system is transformed to the second coordinate in the station-centered spherical coordinate system, including: obtaining the X-axis coordinate, Y-axis coordinate and Z-axis coordinate in the fifth coordinate; determining the radial distance based on the X-axis coordinate, Y-axis coordinate and Z-axis coordinate; determining the first angle based on the Z-axis coordinate and radial distance, and determining the second angle based on the Y-axis coordinate and X-axis coordinate; and determining the second coordinate based on the radial distance, the first angle and the second angle.

[0098] In some embodiments of this application, the formulas for transforming from the station-centered rectangular coordinate system to the station-centered spherical coordinate system are as follows:

[0099]

[0100]

[0101]

[0102] in, This represents the X-axis coordinate in the fifth coordinate system. This represents the Y-axis coordinate in the fifth coordinate system. This represents the Z-axis coordinate in the fifth coordinate system. Indicates radial distance. Indicates the first angle. Indicates the second angle. This represents the second coordinate.

[0103] In step S208 of the above-mentioned terminal satellite alignment method, determining the relative position information between the terminal and the satellite based on the second coordinate includes: obtaining the first angle in the second coordinate; determining the elevation angle between the terminal and the satellite based on the difference between the right angle and the first angle; determining the second angle as the azimuth angle between the terminal and the satellite when the X-axis coordinate in the fifth coordinate is greater than 0, and determining the sum of the second angle and the angle as the azimuth angle between the terminal and the satellite when the X-axis coordinate in the fifth coordinate is less than 0; and determining the relative position information based on the elevation angle and the azimuth angle.

[0104] In some embodiments of this application, the formula corresponding to the elevation angle EL between the station center (terminal) and the satellite is as follows:

[0105]

[0106] The formula for calculating the azimuth angle AL between the station center and the satellite is as follows:

[0107]

[0108] Based on the obtained elevation angle EL and azimuth angle AL, the aforementioned relative position information is determined. This relative position information allows for direct alignment with the terminal satellite, significantly improving the antenna gain between the terminal and the satellite.

[0109] In step S208 of the above-mentioned terminal-satellite alignment method, after adjusting the terminal based on the relative position information, the method further includes: acquiring a first signal sent by the terminal to the satellite; receiving a second signal sent by the satellite to the terminal based on the first signal, wherein the second signal contains updated information of the operating status parameters; and stopping the updating of the operating status parameters when the difference between the updated information and the original information of the operating status parameters is less than a preset threshold.

[0110] In some embodiments of this application, after adjusting the terminal to align with the satellite based on relative position information, a communication link is established between the handheld terminal and the satellite. To further improve positioning accuracy and communication quality, the terminal and the satellite update the satellite's operational status parameters through signal interaction, ensuring that the terminal can track the satellite's precise position in real time. The specific steps are as follows:

[0111] 1. The handheld terminal sends an initial signal (i.e., the first signal) to the satellite. This signal can be a connection request signal or a signal containing the terminal's status information. The purpose of sending the first signal is to initiate two-way communication with the satellite so as to receive subsequent updates from the satellite.

[0112] 2. After receiving the first signal from the handheld terminal, the satellite will send a second signal (containing the latest operational status parameters of the satellite) to the terminal via the downlink. These operational status parameters include, but are not limited to, the six orbital elements (semi-major axis, eccentricity, orbital inclination, pericentric argument, ascending node longitude, and true anomaly), as well as other key information such as signal strength and timestamps. The operational status parameters in the second signal sent by the satellite are updated in real time, reflecting the satellite's actual position and status at the current moment (i.e., the target moment) more accurately than the initial or predicted parameters stored in the terminal.

[0113] 3. After receiving the second signal, the handheld terminal compares the updated operational status parameters contained therein with the original operational status parameters stored internally. By calculating the difference between the two, the terminal can assess whether the real-time update of the satellite position parameters significantly affects the predicted position of the satellite.

[0114] 4. If the difference between the updated information (parameters in the second signal received from the satellite) and the original information (operational status parameters stored in the terminal) is less than a preset threshold, it indicates that the actual position of the satellite is very close to the previously predicted position, the satellite's operational status parameters have not changed significantly, or the change has no substantial impact on the terminal's pointing adjustment. In this case, the handheld terminal can stop receiving updates of the operational status parameters from the satellite, i.e., stop updating the operational status parameters, or, after this update, not update the operational status parameters again. This process helps reduce unnecessary data exchange between the terminal and the satellite, saving communication resources. At the same time, because it no longer needs to frequently process and apply new parameter updates, it also reduces the processing burden on the terminal. If the satellite's operational status parameters change again, or the handheld terminal's position or pointing changes, the terminal will restart receiving and processing satellite operational status parameter updates to maintain the stability of the communication link and maximize signal strength.

[0115] During the above process, the handheld terminal initially determines the satellite's location through its built-in ephemeris. Compared with the existing terminal blind search, it can point to the satellite faster and more accurately, improve the initial access speed, and reduce waiting latency.

[0116] In the aforementioned terminal satellite alignment method, the method further includes: when the terminal is placed horizontally and is in communication with the satellite, acquiring the Received Signal Strength Indication (RSSI) corresponding to the simultaneous reception of downlink signals from the satellite by the two antennas in the terminal, obtaining the left antenna RSSI and the right antenna RSSI; comparing the left antenna RSSI and the right antenna RSSI, controlling the terminal to rotate towards the antenna with the larger RSSI value, until the difference between the left antenna RSSI and the right antenna RSSI is less than a first threshold; when the terminal is placed vertically, acquiring the Received Signal Strength Indication (RSSI) corresponding to the simultaneous reception of downlink signals from the satellite by the two antennas in the terminal, obtaining the upper antenna RSSI and the lower antenna RSSI; comparing the upper antenna RSSI and the lower antenna RSSI, controlling the terminal to rotate towards the antenna with the larger RSSI value, until the difference between the upper antenna RSSI and the lower antenna RSSI is less than a second threshold.

[0117] In some embodiments of this application, the handheld terminal needs to adaptively track after accessing the satellite, and the process is as follows: Figure 6 As shown, Figure 6 This is a schematic diagram of a dual-antenna RSSI tracking process according to an embodiment of this application. Since there are horizontal and vertical angular offsets between the terminal and the satellite beam, it is necessary to first place the terminal horizontally, extract the RSSI, adjust the horizontal angle of the terminal by rotation, then place the handheld terminal vertically, extract the RSSI, and adjust the vertical angle of the terminal by rotation, so that the terminal antenna is aligned with the satellite beam in the horizontal direction.

[0118] Figure 7 This is a schematic diagram of a dual-antenna RSSI tracking principle according to an embodiment of this application. The dual-antenna calibration pattern is as follows. Figure 7 As shown. In dual-antenna calibration, the optimal antenna pointing towards the satellite is in the middle of the main beam range of both antennas; because there are two antennas, the coverage area of ​​the main antenna beam is significantly increased, improving the tolerance for satellite beam alignment errors. When the terminal deviates from the antenna beam center, the next terminal rotation direction can be determined simply by comparing the difference in RSSI between the two antennas.

[0119] The specific steps are as follows:

[0120] Step 1: The terminal is horizontally aligned and pointed.

[0121] When the handheld terminal is placed horizontally and in communication with the satellite, both antennas simultaneously receive downlink signals from the satellite. At any given moment, the two antennas can extract two RSSI values, which are recorded as the left antenna RSSI and the right antenna RSSI respectively. These two RSSI values ​​are compared, and the terminal is controlled to rotate towards the antenna with the larger RSSI value to achieve tracking, until the difference in RSSI intensity between the left and right antennas is less than a first threshold. When the difference in RSSI between the left and right antennas is small, the terminal is considered to be horizontally aligned with the satellite beam.

[0122] Step 2: The terminal is vertically aligned for pointing.

[0123] The handheld terminal is placed vertically, transforming the left and right antennas into a top and bottom antenna. The terminal is rotated until the RSSI strength difference between the top and bottom antennas is less than a second threshold. The overall steps are roughly the same as step 1. Specifically, when the terminal is in communication with the satellite, both antennas simultaneously receive the satellite's downlink signal. At any given moment, the two antennas can extract two RSSI values, which are recorded as the top antenna RSSI and the bottom antenna RSSI, respectively. These two RSSI values ​​are compared, and the terminal is controlled to rotate towards the antenna with the larger RSSI value to achieve tracking, until the RSSI strength difference between the top and bottom antennas is less than the second threshold. When the RSSI differences between the top and bottom antennas are small, the terminal is considered to be vertically aligned with the satellite beam.

[0124] Under access conditions, the handheld terminal can track and align the satellite beam based on dual-antenna RSSI, which reduces the terminal's computational workload compared to existing methods that calculate the direction based on satellite ephemeris information. If the LOS path channel is affected by other losses to the beam caused by the atmosphere and buildings, the RSSI-based tracking mode can continuously search for the optimal channel.

[0125] Figure 8 This is a schematic flowchart of a satellite beam alignment method based on built-in ephemeris and signal tracking according to an embodiment of this application, as shown below. Figure 8 As shown, in step 1-1 of embodiment one, the first coordinate of the satellite in the orbital coordinate system is calculated. Through coordinate transformation, in step 1-2, the elevation angle (or elevation angle) and azimuth angle of the satellite in the station-centered spherical coordinate system are calculated. Based on the elevation angle and azimuth angle, the terminal and the satellite are roughly aligned. Based on the communication between the terminal and the satellite, step 1-3 is entered to update the ephemeris and calibrate the handheld terminal's pointing. When the ephemeris needs to be updated, step 1-1 is returned, and steps 1-1 to 1-3 are repeated until the ephemeris update is no longer needed. Then, step 2-1 of embodiment two is executed to calibrate the pointing of the terminal in the horizontal direction, and step 2-2 is executed to calibrate the pointing of the terminal in the vertical direction.

[0126] The terminal satellite alignment method in this embodiment combines ephemeris calculation and power measurement to solve the problems of slow speed and large delay in initial satellite beam alignment of handheld terminals without relying on ephemeris, and to address the issue of poor channel conditions caused by signal reflection, shadow fading, and other factors when handheld terminals rely solely on ephemeris for alignment. This terminal satellite alignment method improves the initial satellite beam alignment speed of handheld terminals and maintains satellite beam tracking during continuous access, thereby comprehensively improving user channel quality, data transmission rate, and service quality.

[0127] Figure 9 This is a structural diagram of a terminal satellite tracking device according to an embodiment of this application, as shown below. Figure 9 As shown, the device includes:

[0128] The acquisition module 90 is used to acquire the terminal's built-in ephemeris, the initial calibration time between the terminal and the satellite, and the target time for the terminal to access the satellite. The built-in ephemeris includes parameters representing the satellite's operational status in its orbit.

[0129] The determination module 92 is used to determine the first coordinate of the satellite in the orbital coordinate system based on the operating status parameters, the initial calibration time, and the target time;

[0130] The conversion module 94 is used to convert the first coordinate of the satellite in the orbital coordinate system to the second coordinate in the station-centered spherical coordinate system, wherein the center of the sphere in the station-centered spherical coordinate system is the terminal.

[0131] The adjustment module 96 is used to determine the relative position information between the terminal and the satellite based on the second coordinates, and to adjust the terminal based on the relative position information.

[0132] By utilizing the acquisition, determination, conversion, and adjustment modules in the aforementioned terminal-satellite docking device, the initial docking speed between the terminal and the satellite is improved, thereby reducing search time and increasing efficiency. This solves the technical problem of long connection times and low efficiency caused by blind searching when handheld terminals initially connect to satellites.

[0133] In the aforementioned determination module, the operating status parameters include: the six roots of the satellite orbit; this determination module is also used to: determine the average angular velocity of the satellite; determine the mean anomaly angle of the satellite at the target time based on the average angular velocity, the initial calibration time, and the target time; obtain the eccentricity in the six roots of the satellite orbit, and solve Kepler's equations based on the eccentricity and the mean anomaly angle to obtain the off-anomaly angle; obtain the semi-major axis of the elliptical orbit in the six roots of the satellite orbit, and determine the first distance between the satellite and the Earth's center based on the semi-major axis, eccentricity, and off-anomaly angle; determine the true anomaly angle based on the eccentricity and the off-anomaly angle; and determine the first coordinate of the satellite in the orbital coordinate system based on the first distance and the true anomaly angle.

[0134] The aforementioned determining module is also used to obtain the gravitational constant, Earth's mass, and semi-major axis; and based on the gravitational constant, Earth's mass, and semi-major axis, to determine the satellite's average angular velocity.

[0135] The aforementioned conversion module is also used to convert the satellite's first coordinate in the orbital coordinate system to the third coordinate in the geocentric inertial coordinate system; to convert the satellite's third coordinate in the geocentric inertial coordinate system to the fourth coordinate in the geocentric geo-fixed coordinate system; to convert the satellite's fourth coordinate in the geocentric geo-fixed coordinate system to the fifth coordinate in the station-centered rectangular coordinate system, wherein the origin of the station-centered rectangular coordinate system is the terminal; and to convert the satellite's fifth coordinate in the station-centered rectangular coordinate system to the second coordinate in the station-centered spherical coordinate system.

[0136] The aforementioned conversion module is also used to obtain the satellite ascending node longitude, satellite orbital inclination, and pericentric argument from the operating status parameters; determine the first matrix, the second matrix, and the third matrix based on the satellite ascending node longitude, satellite orbital inclination, and pericentric argument, respectively; and convert the first coordinates based on the first matrix, the second matrix, and the third matrix to obtain the third coordinates.

[0137] The aforementioned conversion module is also used to obtain the Earth's rotation angular velocity and the Julian time of the target time; to determine the fourth matrix based on the Earth's rotation angular velocity and the Julian time of the target time; and to convert the third coordinates based on the fourth matrix to obtain the fourth coordinates.

[0138] The aforementioned conversion module is also used to obtain the Earth's radius, the longitude and latitude of the terminal; determine the station center coordinates corresponding to the terminal based on the Earth's radius, the longitude and latitude of the terminal; determine the fifth matrix based on the longitude and latitude of the terminal; and convert the fourth coordinates based on the fifth matrix and the station center coordinates to obtain the fifth coordinates.

[0139] The aforementioned conversion module is also used to obtain the X-axis coordinate, Y-axis coordinate, and Z-axis coordinate in the fifth coordinate system; determine the radial distance based on the X-axis coordinate, Y-axis coordinate, and Z-axis coordinate; determine the first angle based on the Z-axis coordinate and radial distance; determine the second angle based on the Y-axis coordinate and X-axis coordinate; and determine the second coordinate based on the radial distance, the first angle, and the second angle.

[0140] The aforementioned adjustment module is also used to obtain the first angle in the second coordinate system; determine the elevation angle between the terminal and the satellite based on the difference between the right angle and the first angle; determine the second angle as the azimuth angle between the terminal and the satellite when the X-axis coordinate in the fifth coordinate system is greater than 0, and determine the sum of the second angle and the angle as the azimuth angle between the terminal and the satellite when the X-axis coordinate in the fifth coordinate system is less than 0; and determine the relative position information based on the elevation angle and the azimuth angle.

[0141] The aforementioned terminal satellite tracking device also includes an update module 98, which is used to acquire a first signal sent by the terminal to the satellite; receive a second signal sent by the satellite to the terminal based on the first signal, wherein the second signal contains updated information of the operating status parameters; and stop updating the operating status parameters when the difference between the updated information and the original information of the operating status parameters is less than a preset threshold.

[0142] The aforementioned adjustment module is also used to, when the terminal is placed horizontally and is in communication with the satellite, acquire the Received Signal Strength Indication (RSSI) corresponding to the downlink signals received by the satellite simultaneously by the two antennas in the terminal, and obtain the left antenna RSSI and the right antenna RSSI; compare the left antenna RSSI and the right antenna RSSI, and control the terminal to rotate towards the antenna with the larger RSSI value until the difference between the left antenna RSSI and the right antenna RSSI is less than a first threshold; when the terminal is placed vertically, acquire the Received Signal Strength Indication (RSSI) corresponding to the downlink signals received by the satellite simultaneously by the two antennas in the terminal, and obtain the upper antenna RSSI and the lower antenna RSSI; compare the upper antenna RSSI and the lower antenna RSSI, and control the terminal to rotate towards the antenna with the larger RSSI value until the difference between the upper antenna RSSI and the lower antenna RSSI is less than a second threshold.

[0143] It should be noted that, Figure 9 The terminal satellite tracking device shown is used to perform Figure 2 The terminal satellite alignment method shown above is also applicable to this terminal satellite alignment device, and will not be repeated here.

[0144] This application also provides an electronic device, which includes a memory and a processor. The memory stores program instructions, and the processor is connected to the memory to execute program instructions that perform the following functions: acquiring the terminal's built-in ephemeris, the initial calibration time between the terminal and the satellite, and the target time for the terminal to connect to the satellite, wherein the built-in ephemeris includes parameters representing the satellite's operational status in its orbit; determining the first coordinates of the satellite in the orbital coordinate system based on the operational status parameters, the initial calibration time, and the target time; transforming the first coordinates of the satellite in the orbital coordinate system to a second coordinate in a station-centered spherical coordinate system, wherein the center of the sphere in the station-centered spherical coordinate system is the terminal; determining the relative position information between the terminal and the satellite based on the second coordinates, and adjusting the terminal based on the relative position information.

[0145] It should be noted that the aforementioned electronic equipment is used to perform Figure 2 The terminal satellite alignment method shown above is also applicable to this electronic device, and will not be repeated here.

[0146] This application embodiment also provides a non-volatile storage medium, which includes a stored computer program. The device containing the non-volatile storage medium executes the following terminal-satellite alignment method by running the computer program: acquiring the terminal's built-in ephemeris, the initial calibration time between the terminal and the satellite, and the target time for the terminal to connect to the satellite. The built-in ephemeris includes parameters representing the satellite's operational status in its orbit. Based on the operational status parameters, the initial calibration time, and the target time, a first coordinate of the satellite in the orbital coordinate system is determined. The first coordinate of the satellite in the orbital coordinate system is transformed to a second coordinate in a station-centered spherical coordinate system, where the center of the sphere in the station-centered spherical coordinate system is the terminal. The relative position information between the terminal and the satellite is determined based on the second coordinate, and the terminal is adjusted based on the relative position information.

[0147] It should be noted that the aforementioned non-volatile storage media is used for execution. Figure 2 The terminal star-alignment method shown above is also applicable to this non-volatile storage medium, and will not be repeated here.

[0148] This application also provides a computer program product, including computer instructions that, when executed by a processor, implement the steps of the terminal satellite matching method in various embodiments of this application.

[0149] This application also provides a computer program that, when executed by a processor, implements the steps of the terminal satellite matching method in various embodiments of this application.

[0150] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0151] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0152] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0153] 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 units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0154] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0155] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard drive, magnetic disk, or optical disk.

[0156] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A terminal satellite alignment method, characterized in that, include: The terminal's built-in ephemeris, the initial calibration time between the terminal and the satellite, and the target time for the terminal to access the satellite are obtained. The built-in ephemeris includes parameters representing the satellite's operational status in its orbit. Based on the operating status parameters, the calibration initial time, and the target time, determine the first coordinate of the satellite in the orbital coordinate system; The first coordinate of the satellite in the orbital coordinate system is transformed to the second coordinate in the station-centered spherical coordinate system, wherein the center of the sphere in the station-centered spherical coordinate system is the terminal. The relative position information between the terminal and the satellite is determined based on the second coordinates, and the terminal is adjusted based on the relative position information.

2. The method according to claim 1, characterized in that, The operational status parameters include: the number of six orbital elements of the satellite; based on the operational status parameters, the calibration initial time, and the target time, determining the first coordinate of the satellite in the orbital coordinate system includes: Determine the average angular velocity of the satellite; Based on the average angular velocity, the initial calibration time, and the target time, determine the mean anomaly angle of the satellite at the target time; Obtain the eccentricity from the six roots of the satellite orbit, and solve the Kepler equation based on the eccentricity and the mean anomaly to obtain the off-anomaly angle; Obtain the semi-major axis of the elliptical orbit from the six elements of the satellite orbit, and determine the first distance between the satellite and the Earth's center based on the semi-major axis, the eccentricity, and the anomalous angle; The true anterior angle is determined based on the eccentricity and the deviated anterior angle. Based on the first distance and the true anomaly angle, the first coordinates of the satellite in the orbital coordinate system are determined.

3. The method according to claim 2, characterized in that, Determining the average angular velocity of the satellite includes: Obtain the gravitational constant, Earth's mass, and the semi-major axis; The average angular velocity of the satellite is determined based on the gravitational constant, the Earth's mass, and the semi-major axis.

4. The method according to claim 1, characterized in that, Transforming the satellite's first coordinates in the orbital coordinate system to its second coordinates in the station-centered sphere coordinate system includes: Transform the satellite's first coordinates in the orbital coordinate system to its third coordinates in the geocentric inertial coordinate system; Transform the satellite's third coordinate in the geocentric inertial coordinate system to its fourth coordinate in the geocentric-ground-fixed coordinate system; The fourth coordinate of the satellite in the geocentric coordinate system is transformed to the fifth coordinate in the station-centered rectangular coordinate system, wherein the origin of the station-centered rectangular coordinate system is the terminal. Transform the fifth coordinate of the satellite in the station-centered rectangular coordinate system to the second coordinate in the station-centered spherical coordinate system.

5. The method according to claim 4, characterized in that, Transforming the satellite's first coordinates in the orbital coordinate system to its third coordinates in the geocentric inertial coordinate system includes: Obtain the satellite's ascending node longitude, orbital inclination, and pericentric argument from the operational status parameters; The first matrix, the second matrix, and the third matrix are determined based on the longitude of the satellite's ascending node, the satellite's orbital inclination, and the argument of its pericenter, respectively. The first coordinates are transformed based on the first matrix, the second matrix, and the third matrix to obtain the third coordinates.

6. The method according to claim 4, characterized in that, Transforming the satellite's third coordinate in the geocentric inertial coordinate system to its fourth coordinate in the geocentric Earth-fixed coordinate system includes: Obtain the Earth's rotational angular velocity and the Julian time at the target time; The fourth matrix is ​​determined based on the Earth's rotational angular velocity and the Julian time at the target time; The third coordinates are transformed based on the fourth matrix to obtain the fourth coordinates.

7. The method according to claim 4, characterized in that, Transforming the satellite's fourth coordinate in the geocentric coordinate system to its fifth coordinate in the station-centered rectangular coordinate system includes: Obtain the Earth's radius, the longitude and latitude of the terminal; Based on the Earth's radius, the longitude and latitude of the terminal, determine the station center coordinates corresponding to the terminal; The fifth matrix is ​​determined based on the longitude and latitude of the terminal; The fourth coordinates are transformed based on the fifth matrix and the station center coordinates to obtain the fifth coordinates.

8. The method according to claim 4, characterized in that, Transforming the satellite's fifth coordinate in the station-centered rectangular coordinate system to its second coordinate in the station-centered spherical coordinate system includes: Obtain the X-axis, Y-axis, and Z-axis coordinates from the fifth coordinate system; The radial distance is determined based on the X-axis coordinate, the Y-axis coordinate, and the Z-axis coordinate; A first angle is determined based on the Z-axis coordinate and the radial distance, and a second angle is determined based on the Y-axis coordinate and the X-axis coordinate. The second coordinate is determined based on the radial distance, the first angle, and the second angle.

9. The method according to claim 8, characterized in that, Determining the relative position information between the terminal and the satellite based on the second coordinates includes: Obtain the first angle in the second coordinate system; The elevation angle between the terminal and the satellite is determined based on the difference between the right angle and the first angle; If the X-axis coordinate in the fifth coordinate system is greater than 0, the second angle is determined to be the azimuth angle between the terminal and the satellite; if the X-axis coordinate in the fifth coordinate system is less than 0, the sum of the second angle and the straight angle is determined to be the azimuth angle between the terminal and the satellite. The relative position information is determined based on the elevation angle and the azimuth angle.

10. The method according to claim 1, characterized in that, After adjusting the terminal based on the relative position information, the method further includes: Acquire the first signal sent by the terminal to the satellite; The terminal receives a second signal sent by the satellite to the terminal based on the first signal, wherein the second signal contains update information of the operating status parameters; If the difference between the updated information and the original information of the running status parameters is less than a preset threshold, the updating of the running status parameters shall be stopped.

11. The method according to claim 1, characterized in that, The method further includes: When the terminal is placed horizontally and is in communication with the satellite, the Received Signal Strength Indication (RSSI) corresponding to the downlink signal received by the two antennas in the terminal simultaneously from the satellite is obtained, thus obtaining the left antenna RSSI and the right antenna RSSI. Compare the RSSI of the left antenna and the RSSI of the right antenna, and control the terminal to rotate towards the antenna with the larger RSSI value until the difference between the RSSI of the left antenna and the RSSI of the right antenna is less than a first threshold. When the terminal is placed vertically, the Received Signal Strength Indication (RSSI) corresponding to the downlink signal received by the satellite by the two antennas in the terminal is obtained, and the upper antenna RSSI and the lower antenna RSSI are obtained. The upper antenna RSSI and the lower antenna RSSI are compared, and the terminal is controlled to rotate towards the antenna with the larger RSSI value until the difference between the upper antenna RSSI and the lower antenna RSSI is less than a second threshold.

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