CN118432694A - Satellite communication optimization method and device, computer equipment and storage medium - Google Patents

Abstract

The present invention discloses a satellite communication optimization method and device, computer equipment and storage medium, and relates to the field of satellite communication. A satellite communication optimization method, applied to a satellite base station, includes: obtaining the ephemeris information of a first satellite corresponding to a source cell. Determine whether to trigger switching or reselection based on the ephemeris information of the first satellite. If so, obtain the ephemeris information of each satellite in at least one adjacent satellite, and determine the target cell in at least one first cell based on the ephemeris information of each satellite in at least one adjacent satellite. And, adjust the power of the beam corresponding to the source cell, and/or adjust the power of the beam corresponding to the target cell, so that the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell meets the conditions for triggering switching or reselection. Compared with the existing stock mobile phone satellite communication solutions, the satellite communication optimization method provided by the present invention has the characteristics of timely reselection and switching triggering, and can be controlled on demand.

Description

Satellite communication optimization method and device, computer equipment and storage medium

Technical Field

The present invention relates to the field of satellite communication technology, and in particular to a satellite communication optimization method and device, computer equipment and storage medium.

Background technique

The solution of direct mobile phone connection to satellite communication was deployed commercially in the last century. However, because direct mobile phone connection to satellite communication uses a privatized protocol and the industry is closed, the equipment and system costs are relatively high and it has not been promoted in the public market.

In recent years, mobile phone direct satellite communication has become a global research hotspot and has been gradually promoted to the public. There are currently three main modes, namely satellite and cellular multi-mode terminals, 3GPP NTN protocol compatible with cellular and satellite communications, and satellite communication for existing commercial mobile phones. Among them, the existing commercial mobile phone satellite communication mode does not require changes to the user's mobile phone. It enables ordinary mobile phones to directly connect to satellite communications by enhancing satellites and base stations. This mode does not require the replacement of mobile phones, has a fast service penetration rate, and has a broad potential user space.

In the existing technology, beam staring mode is used to realize satellite communication of existing mobile phones. By enhancing satellites and base stations, the direct satellite communication capability of ordinary mobile phones is realized. However, there are the following problems in switching or reselection:

1. Reselection problem: Because it is aimed at existing mobile phones, the air interface communication protocol of existing mobile phones will not be changed. According to the air interface protocol of existing mobile phones, the reselection rules mainly use the S criterion and the R criterion. The S criterion is easier to meet, but there are problems in the implementation of the R criterion, because the R criterion uses the signal strength difference between the target cell and the current resident cell measured by the terminal. When the difference is greater than a certain threshold and remains for a period of time, reselection can occur. However, the satellite beam coverage is relatively uniform, and the signal strength difference between the target cell and the current resident cell is small. It is difficult to trigger reselection or frequent reselection by directly using the reselection solution for existing terminals.

2. The handover problem is similar to the reselection problem. When the existing mobile phone air interface communication protocol is not changed, based on the existing mobile phone air interface protocol, taking the system handover as an example, the events A1-A5 are mainly used. The trigger condition is that the terminal measures the signal strength of the source cell and the target cell. When the difference in the signal strength of the two cells is greater than a certain threshold and remains for a period of time, the handover can occur. However, the satellite beam coverage is relatively uniform, and the difference in signal strength between the target cell and the source cell is small. It is difficult to trigger the handover directly using the existing terminal handover solution or ping-pong handover problems may occur, affecting service stability.

Summary of the invention

The technical problem to be solved by the present invention is: in the prior art, a beam staring mode is used to realize satellite communication of existing mobile phones, and the direct satellite communication capability of ordinary mobile phones is realized by enhancing satellites and base stations. However, in terms of switching or reselection, there are problems with the implementation of the R criterion during the reselection process and the problem of triggering conditions during the switching process.

In view of the above-mentioned deficiencies of the prior art, the following solutions are provided:

In a first aspect, the present invention provides a satellite communication optimization method, which is applied to a satellite base station, including: obtaining the ephemeris information of a first satellite corresponding to a source cell. Determine whether to trigger switching or reselection based on the ephemeris information of the first satellite. If so, obtain the ephemeris information of each satellite in at least one adjacent satellite, and determine the target cell in at least one first cell based on the ephemeris information of each satellite in at least one adjacent satellite. And, adjust the power of the beam corresponding to the source cell, and/or adjust the power of the beam corresponding to the target cell, so that the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell meets the condition for triggering switching or reselection. Wherein, the source cell is the cell currently providing services to the terminal. Each satellite in at least one adjacent satellite is an adjacent satellite of the first satellite. Any first cell in at least one first cell belongs to a satellite in at least one adjacent satellite.

Optionally, judging whether to trigger switching or reselection according to the ephemeris information of the first satellite includes: obtaining the remaining service time of the first satellite relative to the ground location of the terminal and/or the elevation angle of the first satellite relative to the ground location of the terminal according to the ephemeris information of the first satellite and the ground location of the terminal. And, in response to the remaining service time of the first satellite relative to the ground location of the terminal reaching a preset time threshold value, and/or the elevation angle of the first satellite relative to the ground location of the terminal being lower than a preset elevation angle threshold value, triggering switching or reselection.

Optionally, determining a target cell in at least one first cell according to the ephemeris information of each satellite in at least one adjacent satellite includes: obtaining the remaining service time of each first cell in at least one first cell relative to the ground location of the terminal, and/or the elevation angle of each satellite belonging to each first cell in at least one first cell relative to the ground location of the terminal, according to the ephemeris information of each satellite in at least one adjacent satellite and the ground location of the terminal. Sorting each first cell in at least one first cell according to the order of the remaining service time of each first cell in at least one first cell relative to the ground location of the terminal from most to least and/or according to the order of the elevation angle of each satellite belonging to each first cell in at least one first cell relative to the ground location of the terminal from high to low. And, verifying the availability of each first cell in at least one first cell according to the ranking result of each first cell in at least one first cell, and determining the first cell with availability and the highest ranking in at least one first cell as the target cell.

Optionally, adjusting the power of the beam corresponding to the source cell includes: obtaining a path loss value of the minimum elevation angle of the first satellite. Obtaining a ground-to-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value. Obtaining a target range. And adjusting the power of the beam corresponding to the source cell to the target range. The target range is a range greater than 0 and less than or equal to a first difference, and the first difference is the difference between the path loss value of the minimum elevation angle of the satellite and the ground-to-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value.

Optionally, adjusting the power of the beam corresponding to the target cell includes: enhancing the power of the beam corresponding to the target cell within a preset time period, and/or reducing the data signal power of the target cell to enhance the reference signal power of the target cell.

In a second aspect, the present invention provides an optimization device for satellite communication, which is applied to a satellite base station, and the device includes an ephemeris information acquisition module, a judgment module, a target cell determination module and a power adjustment module. Among them, the ephemeris information acquisition module is configured to: obtain the ephemeris information of the first satellite corresponding to the source cell. The source cell is a cell currently providing services to the terminal. The judgment module is configured to: determine whether to trigger switching or reselection according to the ephemeris information of the first satellite. The target cell determination module is configured to: in response to judging whether to trigger switching or reselection according to the ephemeris information of the first satellite, obtain the ephemeris information of each satellite in at least one adjacent satellite, and determine the target cell in at least one first cell according to the ephemeris information of each satellite in at least one adjacent satellite. Each satellite in at least one adjacent satellite is an adjacent satellite of the first satellite. Any first cell in at least one first cell belongs to a satellite in at least one adjacent satellite. The power adjustment module is configured to: adjust the power of the beam corresponding to the source cell, and/or adjust the power of the beam corresponding to the target cell, so that the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell meets the condition for triggering switching or reselection.

Optionally, the judgment module is configured to: obtain the remaining service time of the first satellite relative to the ground location of the terminal and/or the elevation angle of the first satellite relative to the ground location of the terminal according to the ephemeris information of the first satellite and the ground location of the terminal. And, in response to the remaining service time of the first satellite relative to the ground location of the terminal reaching a preset time threshold value, and/or the elevation angle of the first satellite relative to the ground location of the terminal being lower than a preset elevation angle threshold value, trigger switching or reselection.

Optionally, the target cell determination module is configured to: obtain the remaining service time of each first cell in at least one first cell relative to the ground location of the terminal, and/or the elevation angle of each satellite to which each first cell in at least one first cell belongs relative to the ground location of the terminal, according to the ephemeris information of each satellite in at least one adjacent satellite and the ground location of the terminal. Sort the first cells in at least one first cell in the order of the remaining service time of each first cell in at least one first cell relative to the ground location of the terminal from most to least and/or in the order of the elevation angle of each satellite to which each first cell in at least one first cell belongs relative to the ground location of the terminal from high to low. And, verify the availability of each first cell in at least one first cell according to the sorting result of each first cell in at least one first cell, and determine the first cell in at least one first cell that has availability and is ranked the highest as the target cell.

Optionally, the power adjustment module includes: a first power adjustment unit and/or a second power adjustment unit. Among them, the first power adjustment unit is configured to: obtain the path loss value of the minimum elevation angle of the first satellite. Obtain the ground-to-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value. Obtain a target range, the target range is a range greater than 0 and less than or equal to a first difference, the first difference is the difference between the path loss value of the minimum elevation angle of the satellite and the ground-to-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value. And, adjust the power of the beam corresponding to the source cell to the target range. The second power adjustment unit is configured to: enhance the power of the beam corresponding to the target cell within a preset time period, and/or reduce the data signal power of the target cell to enhance the reference signal power of the target cell.

In a third aspect, the present invention provides a computer device, including a memory and a processor, wherein a computer program is stored in the memory, and when the processor runs the computer program stored in the memory, the processor executes the above-mentioned satellite communication optimization method.

In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the processor executes the above-mentioned satellite communication optimization method.

The satellite communication optimization method and device, computer equipment and storage medium provided by the present invention determine the actual triggering of switching or reselection based on ephemeris information, and determine a cell that can provide network services for a longer time and has better signal strength as a target cell based on the ephemeris information, and then construct a power difference that meets the switching or reselection conditions by adjusting the power corresponding to the source cell and/or adjusting the power corresponding to the target cell, so that the switching or reselection conditions can be constructed in the satellite communication system to solve the problem of abnormal triggering of switching or reselection of existing mobile phones. Compared with the existing satellite communication solutions for existing mobile phones, the satellite communication optimization method provided by the present invention has the characteristics of timely reselection and switching triggering, and can be controlled on demand, which can improve the user service experience and lay the foundation for the future satellite communication networking for existing mobile phones.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of an application scenario of a satellite communication optimization method in an embodiment of the present invention;

FIG2 is a flow chart of a satellite communication optimization method according to an embodiment of the present invention;

FIG3 is a flow chart of another satellite communication optimization method according to an embodiment of the present invention;

FIG4 is a flow chart of another satellite communication optimization method according to an embodiment of the present invention;

FIG5 is a flow chart of another satellite communication optimization method according to an embodiment of the present invention;

FIG6 is a structural diagram of a satellite communication optimization device according to an embodiment of the present invention;

FIG7A is a structural diagram of another satellite communication optimization device according to an embodiment of the present invention;

7B is a structural diagram of another satellite communication optimization device according to an embodiment of the present invention;

FIG7C is a structural diagram of yet another satellite communication optimization device according to an embodiment of the present invention;

FIG8 is a flowchart of a satellite communication optimization device in an example of an embodiment of the present invention;

FIG. 9 is a structural diagram of another computer device in an embodiment of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the technical solution of the present invention, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

It should be understood that the specific embodiments and drawings described herein are only used to explain the present invention rather than to limit the present invention.

It can be understood that, in the absence of conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other.

It can be understood that, for the convenience of description, the drawings of the present invention only show the parts related to the present invention, while the parts irrelevant to the present invention are not shown in the drawings.

It can be understood that each unit and module involved in the embodiments of the present invention may correspond to only one physical structure, or may be composed of multiple physical structures, or multiple units and modules may be integrated into one physical structure.

It can be understood that, in the absence of conflict, the functions and steps marked in the flowcharts and block diagrams of the present invention may occur in an order different from that marked in the drawings.

It is understood that the flowcharts and block diagrams of the present invention illustrate the possible architectures, functions, and operations of the systems, devices, equipment, and methods according to the embodiments of the present invention. Each box in the flowchart or block diagram may represent a unit, module, program segment, or code, which contains executable instructions for implementing the specified functions. Moreover, each box or combination of boxes in the block diagram and flowchart may be implemented by a hardware-based system that implements the specified functions, or may be implemented by a combination of hardware and computer instructions.

It can be understood that the units and modules involved in the embodiments of the present invention can be implemented by software or hardware. For example, the units and modules can be located in a processor.

First, the specific terms involved in the embodiments of the present invention are explained as follows:

1. Satellite ephemeris information

Satellite ephemeris information refers to data describing the satellite's orbit in space. This data includes information such as the satellite's position, speed, attitude, and the parameters and predictions of the satellite's orbit. Ephemeris information is very important for satellite orbit tracking, communication, navigation, and other aspects.

Specifically, the satellite's ephemeris information usually includes the following:

Three-dimensional position of a satellite: describes the specific position of a satellite in space, usually expressed using an Earth-centered inertial coordinate system or an Earth-centered Earth-fixed coordinate system.

Satellite velocity: describes the velocity vector of the satellite in orbit, including velocity magnitude and direction.

Satellite attitude: describes the satellite's attitude angles, including pitch angle, yaw angle, etc.

Satellite orbital parameters: including orbital altitude, orbital inclination, orbital period and other parameters.

Predicted orbit of satellite: Predict the future orbit of the satellite based on historical orbit data and mathematical models.

These ephemeris information are generated and updated by the ground control center or the satellite's own navigation system to ensure the accurate operation and communication of the satellite. Ephemeris information plays a vital role in satellite navigation, communication, remote sensing and other applications.

2. Community

The cells in a satellite communication system are usually called "beams". In a satellite communication system, a beam refers to a directional beam of signals transmitted or received by a satellite, which is used to focus the signal on a specific area or user equipment. Each beam has independent frequency, power, coverage and other parameters, which are used to manage and control the allocation of communication resources.

Therefore, when referring to cells in satellite communication systems, it is usually referring to beams. The division and adjustment of beams can be adjusted according to factors such as user needs and communication quality to optimize the utilization of communication resources and improve communication quality.

Some embodiments of the present invention provide a satellite communication optimization method that can be applied to the scenario shown in FIG. 1 .

Some embodiments of the present invention provide a satellite communication optimization method applied to a satellite base station.

As shown in Figure 1, the arrow indicates the moving direction of the satellite. In the process of the satellite SAT1 moving from a position far away from the terminal UE to the zenith of the terminal UE, the elevation angle α of the satellite SAT1 relative to the ground position of the terminal UE (the angle between the line L1 connecting the satellite SAT and the terminal UE and the tangent L2 of the ground position of the terminal UE) gradually increases and becomes closer and closer to 90°, the communication distance between the cell beam1 and the terminal UE is getting closer and closer, and the signal strength is getting stronger and stronger. Therefore, the cell beam1 can start to provide network services to the terminal UE at a certain moment in this process. As the satellite SAT1 reaches the zenith of the ground position of the terminal UE, the elevation angle α of the satellite SAT1 relative to the ground position of the terminal UE is 90°, the communication distance between the cell beam1 and the terminal UE is the shortest, and the signal strength is the strongest. After satellite SAT1 reaches the zenith of the ground location where the terminal UE is located, the elevation angle α of satellite SAT1 relative to the ground location where the terminal UE is located drops below 90° and gets closer and closer to 0°. Satellite SAT1 will be farther and farther away from the area where the terminal UE is located. As the first satellite SAT1 moves away, the communication distance between cell beam1 and the terminal UE becomes larger and larger, and the signal strength becomes weaker and weaker. In order to ensure the network quality of the terminal UE, it is necessary to find another cell beam2. Compared with cell beam1, cell beam2 has a closer communication distance with the terminal UE and a better signal strength, so that cell beam2 can replace cell beam1 to provide network services for the terminal UE. Satellite SAT2 is the satellite to which cell beam2 belongs.

As shown in FIG. 2 , some embodiments of the present invention provide a satellite communication optimization method applied to a satellite base station. The satellite communication optimization method includes steps 201 to 204 .

Step 201: Acquire ephemeris information of a first satellite corresponding to a source cell.

In step 201, the source cell is a cell currently providing services to the terminal.

Exemplarily, the source cell may be the cell beam1 in FIG. 1 , and the first satellite may be the satellite SAT1 in FIG. 1 .

Step 202: Determine whether to trigger switching or reselection according to the ephemeris information of the first satellite.

It can be understood that, based on the ephemeris information of the first satellite, information such as the operating status and attitude of the first satellite can be obtained, so that it can be determined whether to trigger switching or reselection.

It can be understood that, for the first satellite, there may be multiple terminals communicating with the first satellite, and the multiple terminals may all be in a connected state, or the multiple terminals may all be in an idle state, or the multiple terminals may be partially in a connected state and partially in an idle state. Therefore, when the multiple terminals are all in a connected state, only switching can be triggered, that is, each of the multiple terminals is switched to the target cell. When the multiple terminals are all in an idle state, only reselection can be triggered, that is, each of the multiple terminals is reselected to the target cell. When the multiple terminals are partially in a connected state and partially in an idle state, switching and reselection can be triggered, that is, the terminals in the connected state among the multiple terminals are switched to the target cell, and the terminals in the idle state among the multiple terminals are reselected to the target cell.

It can be understood that for a specific terminal, the terminal is in one of the connected state and the idle state, and will not be in both states at the same time. Therefore, for a specific terminal, the first satellite triggers a mode of switching and reselection.

In some embodiments, as shown in FIG. 3 , the implementation method of step 202 includes steps 2021 to 2022 .

Step 2021: Obtain the remaining service time of the first satellite relative to the ground location of the terminal and/or the elevation angle of the first satellite relative to the ground location of the terminal according to the ephemeris information of the first satellite and the ground location of the terminal.

It can be understood that based on the ephemeris information of the first satellite, the orbit, current position information, running speed and other information of the first satellite can be obtained. Therefore, based on the current position information of the first satellite and the ground position of the terminal, it is possible to calculate how long it takes for the first satellite to move from its current position to a position that cannot cover the ground position of the terminal (for example, the horizon of the ground position in the area), that is, the remaining service time of the first satellite relative to the ground position of the terminal.

It can be understood that, as shown in Figure 1, taking the first satellite as satellite SAT1 and the terminal as terminal UE as an example, the current position information of satellite SAT1 can be obtained according to the ephemeris information of satellite SAT1, and the elevation angle α of satellite SAT1 relative to the ground position of terminal UE can be calculated according to the current position information of satellite SAT1 and the ground position of terminal UE.

Step 2022: In response to the remaining service time of the first satellite relative to the ground location of the terminal reaching a preset time threshold, and/or the elevation angle of the first satellite relative to the ground location of the terminal being lower than a preset elevation angle threshold, triggering switching or reselection.

It can be understood that whether to trigger switching or reselection is determined based on the remaining service time of the first satellite relative to the ground location of the terminal and/or the elevation angle of the first satellite relative to the ground location of the terminal.

Exemplarily, as shown in Figure 1, taking the first satellite as satellite SAT1 and the terminal as terminal UE, as the satellite SAT1 moves, the satellite SAT1 will first reach the zenith of the ground position where the terminal UE is located from a ground position far away from the terminal UE. After the satellite SAT1 passes the zenith of the terminal UE, the satellite SAT1 will become farther and farther away from the ground position where the terminal UE is located. By setting a preset time threshold value and/or a preset elevation angle threshold value, switching or reselection can be triggered before the satellite SAT1 is completely unable to communicate with the terminal UE (for example, the satellite SAT1 reaches the horizon of the ground position where the terminal UE is located, and the elevation angle α of the satellite SAT1 relative to the ground position where the terminal UE is located is 0), and the terminal can be transferred to another satellite (for example, satellite SAT2) in time, thereby avoiding the terminal UE suddenly disconnecting the communication with the satellite SAT1 and causing the terminal network to be interrupted.

It can be understood that, in the case of determining to trigger handover or reselection, a target cell needs to be determined to transfer the terminal to the target cell.

Step 203: Acquire ephemeris information of each satellite in at least one adjacent satellite, and determine a target cell in at least one first cell according to the ephemeris information of each satellite in at least one adjacent satellite.

In step 203, each satellite in the at least one neighboring satellite is a neighboring satellite of the first satellite. Any first cell in the at least one first cell belongs to a satellite in the at least one neighboring satellite.

It is understandable that the first satellite may have multiple adjacent satellites, and each satellite may have multiple first cells, so that the target cell can be determined in at least one first cell. According to the ephemeris information of the satellite, the position and speed of the satellite can be determined, so that the target cell can be determined in at least one first cell according to the ephemeris information of each satellite in at least one adjacent satellite.

In some embodiments, as shown in FIG. 4 , step 203 may include steps 2031 to 2033 .

Step 2031: Obtain the remaining service time of each first cell in at least one first cell relative to the ground location of the terminal, and/or the elevation angle of each satellite to which each first cell in at least one first cell belongs relative to the ground location of the terminal, based on the ephemeris information of each satellite in at least one adjacent satellite and the ground location of the terminal.

It can be understood that the specific implementation method of step 2031 is similar to the specific implementation method of step 2021. According to the ephemeris information of each satellite in at least one adjacent satellite, the orbit, current position information, and running speed of each satellite in at least one adjacent satellite can be obtained, so that according to the current position information of each satellite in at least one adjacent satellite and the ground position of the terminal, it can be calculated how long it takes for each satellite in at least one adjacent satellite to move from the current position to a position that cannot cover the ground position of the terminal, that is, the remaining service time of each satellite in at least one adjacent satellite relative to the ground position of the terminal.

It can be understood that the current position information of each satellite in at least one adjacent satellite can be obtained based on the ephemeris information of each satellite in at least one adjacent satellite, and the elevation angle of each satellite in at least one adjacent satellite relative to the ground position of the terminal can be calculated based on the current position information of each satellite in at least one adjacent satellite and the ground position of the terminal, that is, the elevation angle of each satellite belonging to each first cell in at least one first cell relative to the ground position of the terminal.

Step 2032: sort the at least one first cell in the order of the remaining service time of each first cell relative to the ground location of the terminal from most to least and/or in the order of the elevation angles of the satellites belonging to each first cell in the at least one first cell relative to the ground location of the terminal from high to low.

It can be understood that a cell with a longer remaining service time relative to the ground location of the terminal can provide longer service, thereby minimizing the number of terminal-side handovers or reselections. The closer the elevation angle relative to the ground location of the terminal is to 90°, the better the signal for communication between the corresponding cell and the terminal, thereby providing better network services to the terminal.

Exemplarily, two weight coefficients may be set. In the process of sorting each of the at least one first cell according to the order of the remaining service time of each of the at least one first cell relative to the ground location of the terminal from most to least and according to the order of the elevation angles of the satellites belonging to each of the at least one first cell relative to the ground location of the terminal from high to low, the remaining service time of each of the at least one first cell relative to the ground location of the terminal and the elevation angles of the satellites belonging to each of the at least one first cell relative to the ground location of the terminal are multiplied by the corresponding weight coefficients, so as to sort each of the at least one first cell.

Step 2033: Verify the availability of each first cell in the at least one first cell according to the ranking result of each first cell in the at least one first cell, and determine the first cell in the at least one first cell that has availability and is ranked highest as the target cell.

It can be understood that before determining the target cell, it is necessary to determine the availability of each first cell in at least one first cell. Exemplarily, the resource availability of the first cell ranked first is obtained through the Xn interface of the satellite base station corresponding to the source cell and the target base station corresponding to the first cell ranked first. If it is unavailable, the first cell ranked second is selected according to the ranking, and so on.

Step 204: adjust the power of the beam corresponding to the source cell, and/or adjust the power of the beam corresponding to the target cell, so that the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell meets the conditions for triggering switching or reselection.

In some embodiments, as shown in FIG. 5 , in step 204 , the method for adjusting the power of the beam corresponding to the source cell includes steps 2041 to 2044 .

Step 2041: Obtain the path loss value of the minimum elevation angle of the first satellite.

It can be understood that, as shown in FIG1 , taking the first satellite as satellite SAT1 and the terminal as terminal UE as an example, the smaller the elevation angle of satellite SAT1 relative to the ground position of terminal UE, the farther the terminal UE is from satellite SAT1, and the longer the signal transmission path, the greater the path loss, and thus, a maximum loss value can be artificially set to limit the power range of the source cell. Exemplarily, when the constellation design of the first satellite is initially performed, the minimum elevation angle supported by the first satellite is determined, so that the path loss value of the minimum elevation angle of the first satellite can be set as the maximum loss value.

Exemplarily, the signal propagation distance may be determined according to the minimum elevation angle of the first satellite, and the path loss value Pathlossmax at the minimum elevation angle of the first satellite may be calculated according to the signal propagation distance and the wavelength of the signal.

Step 2042: Obtain the ground-to-space loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value.

Exemplarily, the signal propagation distance can be determined according to a preset elevation angle threshold value, and the ground-to-space loss value Pathloss1 when the elevation angle of the coverage area of the first satellite is the preset elevation angle threshold value can be calculated according to the signal propagation distance and the signal wavelength.

Step 2043: Get the target range.

In step 2043, the target range is a range greater than 0 and less than or equal to a first difference, where the first difference is the difference between the path loss value at the minimum elevation angle of the satellite and the ground-to-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value.

Exemplarily, the target range is the interval (0, Pathlossmax-Pathloss1].

Step 2044: adjust the power of the beam corresponding to the source cell to the target range.

It can be understood that the power of the beam corresponding to the source cell is adjusted to the interval (0, Pathlossmax-Pathloss1], that is, the power of the beam corresponding to the source cell can be reduced, so that the difference between the power of the beam corresponding to the target cell and the reduced power of the beam corresponding to the source cell may meet the conditions for triggering switching or reselection.

In some embodiments, in step 204, the method for implementing adjusting the power of the beam corresponding to the target cell includes: enhancing the power of the beam corresponding to the target cell within a preset time period, and/or reducing the data signal power of the target cell to enhance the reference signal power of the target cell.

It can be understood that enhancing the power of the beam corresponding to the target cell within a preset time period, and/or reducing the data signal power of the target cell to enhance the reference signal power of the target cell, may refer to temporarily enhancing the power of the beam corresponding to the target cell for a period of time after triggering movement or reselection, and/or reducing the data signal power of the target cell to enhance the reference signal power of the target cell.

Exemplarily, the satellite corresponding to the target cell can reserve a power margin for the beam corresponding to the target cell to meet the temporary enhancement of the target cell signal, and release the power when the switching or reselection is completed. The terminal side mainly measures the reference signal power when switching or reselecting, so that the reference signal power can be enhanced by reducing the data power, and the data and reference signal power can be restored when the switching or reselection is completed.

It can be understood that if after the power of the beam corresponding to the source cell is reduced, the difference between the power of the beam corresponding to the target cell and the reduced power of the beam corresponding to the source cell still does not meet the conditions for triggering switching or reselection, the power of the beam corresponding to the target cell can be enhanced so that the difference between the enhanced power of the beam corresponding to the target cell and the reduced power of the beam corresponding to the source cell meets the conditions for triggering switching or reselection.

Exemplarily, the power of the beam corresponding to the target cell may be adjusted first. If, after adjusting the power of the beam corresponding to the target cell, the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell meets the condition for triggering switching or reselection, the power of the beam corresponding to the source cell may not be adjusted. However, if, after adjusting the power of the beam corresponding to the target cell, the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell still does not meet the condition for triggering switching or reselection, the power of the beam corresponding to the source cell may be adjusted again so that the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell meets the condition for triggering switching or reselection.

Exemplarily, the power of the beam corresponding to the source cell and the power of the beam corresponding to the target cell may also be adjusted simultaneously, thereby speeding up the process of triggering switching or reselection.

In a satellite communication optimization method provided by an embodiment of the present invention, the actual triggering of switching or reselection is determined based on ephemeris information, and a cell that can provide network services for a longer time and has better signal strength is determined as a target cell based on the ephemeris information, and then a power difference that meets the switching or reselection conditions is constructed by adjusting the power corresponding to the source cell and/or adjusting the power corresponding to the target cell, so that the conditions for switching or reselection can be constructed in the satellite communication system to solve the problem of abnormal triggering of switching or reselection of existing mobile phones. Compared with the existing satellite communication solutions for existing mobile phones, the satellite communication optimization method provided by an embodiment of the present invention has the characteristics of timely reselection and switching triggering, and can be controlled on demand, which can improve user service experience and lay the foundation for the future satellite communication networking for existing mobile phones.

Some embodiments of the present invention provide a satellite communication optimization device, which is applied to a satellite base station. As shown in FIG. 6 , the optimization device 600 includes an ephemeris information acquisition module 601 , a judgment module 602 , a target cell determination module 603 and a power adjustment module 604 .

The ephemeris information acquisition module 601 is configured to: acquire the ephemeris information of the first satellite corresponding to the source cell. The source cell is the cell currently providing services to the terminal.

The determination module 602 is configured to determine whether to trigger switching or reselection according to the ephemeris information of the first satellite.

In some embodiments, the judgment module 602 is configured to: obtain the remaining service time of the first satellite relative to the ground location of the terminal and/or the elevation angle of the first satellite relative to the ground location of the terminal according to the ephemeris information of the first satellite and the ground location of the terminal. And, determine whether to trigger switching or reselection according to the remaining service time of the first satellite relative to the ground location of the terminal and/or the elevation angle of the first satellite relative to the ground location of the terminal. In response to the remaining service time of the first satellite relative to the ground location of the terminal reaching a preset time threshold, and/or the elevation angle of the first satellite relative to the ground location of the terminal being lower than a preset elevation threshold, switching or reselection is triggered.

The target cell determination module 603 is configured to: in response to determining that a handover or reselection is triggered according to the ephemeris information of the first satellite, obtain the ephemeris information of each satellite in at least one adjacent satellite, and determine the target cell in at least one first cell according to the ephemeris information of each satellite in at least one adjacent satellite. Each satellite in at least one adjacent satellite is an adjacent satellite of the first satellite. Any first cell in at least one first cell belongs to a satellite in at least one adjacent satellite.

In some embodiments, the target cell determination module 603 is configured to: obtain the remaining service time of each first cell in at least one first cell relative to the ground location of the terminal, and/or the elevation angle of each satellite to which each first cell in at least one first cell belongs relative to the ground location of the terminal, according to the ephemeris information of each satellite in at least one adjacent satellite and the ground location of the terminal. Sort the first cells in at least one first cell in the order of the remaining service time of each first cell in at least one first cell relative to the ground location of the terminal from most to least and/or in the order of the elevation angle of each satellite to which each first cell in at least one first cell belongs relative to the ground location of the terminal from high to low. And, verify the availability of each first cell in at least one first cell according to the sorting result of each first cell in at least one first cell, and determine the first cell in at least one first cell that has availability and is ranked the highest as the target cell.

The power adjustment module 604 is configured to: adjust the power of the beam corresponding to the source cell, and/or adjust the power of the beam corresponding to the target cell, so that the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell meets the conditions for triggering switching or reselection.

In some embodiments, as shown in FIGS. 7A to 7C , the power adjustment module 604 includes a first power adjustment unit 6041 and/or a second power adjustment unit 6042 .

The first power adjustment unit 6041 is configured to: obtain the path loss value of the minimum elevation angle of the first satellite. Obtain the ground-to-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value. Obtain a target range, the target range is a range greater than 0 and less than or equal to a first difference, the first difference is the difference between the path loss value of the minimum elevation angle of the satellite and the ground-to-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value. And, adjust the power of the beam corresponding to the source cell to the target range. And/or

The second power adjustment unit 6042 is configured to: enhance the power of the beam corresponding to the target cell within a preset time period, and/or reduce the data signal power of the target cell to enhance the reference signal power of the target cell.

The specific scheme and beneficial effects of a satellite communication optimization device 700 provided in some embodiments of the present invention can be referred to the relevant description of a satellite communication optimization method provided in some embodiments of the present invention, which will not be repeated here.

The following is an example to illustrate a satellite communication optimization device provided by some embodiments of the present invention.

The idea of this example is to optimize the air interface switching or reselection process of the mobile phone direct satellite communication application mode using the existing commercial mobile phone direct satellite communication, and propose a satellite communication optimization device. The main purpose is to solve the problem that the existing mobile phone air interface protocol is difficult to trigger switching/reselection using RSRP measurement. The optimization device is deployed at the satellite base station, and jointly judges the attributes of the cell (target cell or source cell) based on the ephemeris information and the area to be covered, helps the terminal find a suitable target cell, and simulates the triggering conditions of ground switching or reselection by controlling the beam signal strength difference, and constructs the switching or reselection triggering conditions supported by the existing mobile phones through beam power adjustment.

On the one hand, the optimization device obtains the ephemeris information of the satellite constellation from the satellite base station, which is used to calculate the satellite trajectory serving the satellite base station in real time, and uses the optimization device to perform calculations and judgments. On the other hand, the optimization device controls the transmission power of the corresponding beam of the satellite base station according to the judgment result, and constructs the triggering condition of switching or reselection to trigger the terminal to reselect or switch.

In this example, the detailed workflow of the optimization device is shown in FIG8 . The start judgment refers to: starting the judgment on whether to trigger switching or reselection. The optimization device obtains the ephemeris information of the satellite through the base station (the base station uses the network management platform) to obtain the motion state of the satellite serving the satellite base station, which includes the elevation angle, the remaining service time, etc. When the current service satellite passes the top and gradually moves away from the coverage area (always staring at the area, and the communication distance gradually increases after passing the top) and reaches the threshold value, the switching or reselection of the target satellite beam selection is triggered, where the threshold can be the remaining service time or the elevation angle reaching a certain angle. The optimization device determines whether to trigger switching or reselection, and the judgment method can be obtained by calculating the relative position of the satellite through the ephemeris information. For example, the constellation satellite passes the top for N seconds, and the switching or reselection is triggered when M seconds are left, that is, the threshold value of the remaining service time is set to M seconds, where N is greater than or equal to M, and N and M are both positive numbers. For example, a threshold value for triggering elevation angle may be set, and switching or reselection may be triggered when the elevation angle of the coverage area is lower than the set elevation angle threshold value.

Evaluating the beam coverage status means that after the decision triggers handover or reselection, multiple candidate cells (beams) are provided according to the constellation ephemeris information and sorted according to the set rules, which may be the longest overhead time or the shortest communication distance, etc. As shown in Figure 1, SAT1 and SAT2 pass through the target area in the direction of movement, and it can be known from the ephemeris that beam1 is the source cell and beam2 is the target cell.

The optimization device obtains the operating status of the surrounding satellites through the base station. It also evaluates the corresponding indicators of the neighboring satellites corresponding to the trigger threshold, sorts the cells of the neighboring satellites (according to the remaining service time or pitch angle, etc.), and after determining the appropriate cell, further determines the availability of the target cell. Through the Xn interface between the source base station and the target base station, it obtains the resource availability of the corresponding cell of the target base station. If it is unavailable, the second target satellite is selected according to the sorting, and so on. In this way, the best target cell can be determined.

The value of beam power control is to evaluate the power adjustment range of each beam after determining the target cell and the source cell. For the target cell, the network side (base station side) determines the current beam power adjustable (increase) range based on the power limit allocated by the satellite to the beam; for the source cell, the path loss difference can be calculated based on the system design minimum elevation angle and the elevation angle when triggering switching or reselection, which is the power adjustment (reduction) range of the source cell.

Power reduction is mainly used to trigger the source cell of the switching or reselection conditions. The Pathlossmax value is introduced, which is the path loss corresponding to the minimum elevation angle of the satellite. The minimum elevation angle is defined as the angle between the user-satellite connection line and the ground tangent. The smaller the angle, the farther the user is from the satellite, and the greater the path loss. Usually, the minimum elevation angle supported is determined during constellation design. This is the maximum loss within the satellite's service range (the ground-to-air distance is the farthest at this time, and the terminal receiving power is the lowest under the same satellite transmission power). Pathloss1 is the ground-to-air path loss when triggering switching or reselection. The value range should be between the minimum elevation angle Pathlossmax and the 90 elevation angle Pathloss. Then the power reduction range is (0, Pathlossmax-Pathloss1], which means that the power of the source cell should be adjusted to this range.

If the power reduction of the source beam (cell) still cannot meet the received power difference required by the switching or reselection triggering criteria, the power of the target beam (cell) can be further increased.

The power increase is mainly used for the power of the target satellite cell (beam) selected by the device. There are many ways to increase the power. First, the satellite reserves power margin for the beam to trigger switching or reselection to meet the temporary enhancement of the target cell signal, and releases the power when the switching or reselection is completed. Second, the terminal triggers switching or reselection mainly to measure the reference signal power. The reference signal power can be enhanced by reducing the data power, and the data and reference signal power are restored when the switching or reselection is completed.

Downlink power control, reduce the source cell transmit power with a set step size, or increase the target cell transmit power, construct the received signal strength difference, meet the switching or reselection triggering conditions, and thus trigger switching or reselection. For reselection, meet Rn>Rs, and keep the reselection decision timer length; for switching, meet EventA triggering conditions, and keep the switching decision timer length. Trigger switching or reselection, and complete user migration after meeting the reselection or switching conditions. If the cell resources are limited or faulty, you can try in sequence according to the cell ranking generated when starting the judgment, and finally find the target cell.

This example is aimed at direct satellite communication for existing mobile phones. A set of devices set on the base station side is designed to optimize the switching or reselection process and improve the user switching or reselection performance. Based on the switching or reselection characteristics of existing mobile phones, this example adopts a method in which the network side determines the timing of switching or reselection, and the network side constructs the switching or reselection triggering conditions. This method can solve the problem of abnormal triggering of switching or reselection of existing mobile phones. This example uses ephemeris information to assist the network side in calculating and determining the switching or reselection time point to serve ordinary commercial mobile phones.

Some embodiments of the present invention provide a computer device. As shown in FIG. 9 , the computer device 900 includes a memory 901 and a processor 902. The memory 901 stores a computer program. When the processor 902 runs the computer program stored in the memory 901, the processor 902 executes the above-mentioned satellite communication optimization method.

The specific scheme and beneficial effects of a computer device provided by some embodiments of the present invention can be referred to the relevant description of a satellite communication optimization method provided by some embodiments of the present invention, which will not be repeated here.

Some embodiments of the present invention provide a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the processor executes the above-mentioned satellite communication optimization method.

The specific scheme and beneficial effects of a computer-readable storage medium provided by some embodiments of the present invention can be referred to the relevant description of a satellite communication optimization method provided by some embodiments of the present invention, which will not be repeated here.

It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims (11)

1. An optimization method for satellite communication, which is applied to a satellite base station, comprises the following steps:

acquiring ephemeris information of a first satellite corresponding to a source cell; the source cell is a cell currently providing service for the terminal;

Judging whether to trigger switching or reselection according to the ephemeris information of the first satellite; if yes, acquiring the ephemeris information of each satellite in at least one adjacent satellite, and determining a target cell in at least one first cell according to the ephemeris information of each satellite in the at least one adjacent satellite; each satellite of the at least one adjacent satellite is an adjacent satellite to the first satellite; any one of the at least one first cell belongs to one of the at least one adjacent satellites; and

And adjusting the power of the beam corresponding to the source cell and/or adjusting the power of the beam corresponding to the target cell so that the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell meets the condition of triggering handover or reselection.

2. The method of optimizing satellite communications according to claim 1, wherein said determining whether to trigger a handoff or reselection based on ephemeris information of the first satellite comprises:

acquiring the residual service duration of the first satellite relative to the ground position of the terminal and/or the elevation angle of the first satellite relative to the ground position of the terminal according to the ephemeris information of the first satellite and the ground position of the terminal; and

And triggering switching or reselection in response to the residual service duration of the first satellite relative to the ground position of the terminal reaching a preset time threshold value and/or the elevation angle of the first satellite relative to the ground position of the terminal being lower than a preset elevation angle threshold value.

3. The method of optimizing satellite communications according to claim 1 or 2, wherein said determining a target cell in at least one first cell based on ephemeris information of each of said at least one neighboring satellites comprises:

Acquiring the residual service duration of each first cell in the at least one first cell relative to the ground position of the terminal according to the ephemeris information of each satellite in the at least one adjacent satellite and the ground position of the terminal, and/or the elevation angle of each satellite in the at least one first cell relative to the ground position of the terminal;

Sorting the first cells in the at least one first cell according to the order of the remaining service duration of the first cells in the at least one first cell from more to less relative to the ground position of the terminal and/or according to the order of the elevation angle of the satellite of the first cells in the at least one first cell from higher to lower relative to the ground position of the terminal; and

And verifying the availability of each first cell in the at least one first cell according to the sequencing result of each first cell in the at least one first cell, and determining the first cell with the availability and the forefront sequencing in the at least one first cell as the target cell.

4. The method of optimizing satellite communications according to claim 1, wherein said adjusting the power of the beam corresponding to the source cell comprises:

Acquiring a path loss value of the minimum elevation angle of the first satellite;

Acquiring a ground-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value;

Acquiring a target range, wherein the target range is a range which is larger than 0 and smaller than or equal to a first difference value, and the first difference value is a difference value between a path loss value of the minimum elevation angle of the satellite and a ground-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value; and

And adjusting the power of the beam corresponding to the source cell into the target range.

5. The method of optimizing satellite communications according to claim 1, wherein said adjusting the power of the beam corresponding to the target cell comprises:

And enhancing the power of a beam corresponding to the target cell in a preset period, and/or reducing the data signal power of the target cell to enhance the reference signal power of the target cell.

6. An optimization apparatus for satellite communications, applied to a satellite base station, the apparatus comprising:

an ephemeris information acquisition module configured to: acquiring ephemeris information of a first satellite corresponding to a source cell; the source cell is a cell currently providing service for the terminal;

A judgment module configured to: judging whether to trigger switching or reselection according to the ephemeris information of the first satellite;

a target cell determination module configured to: responding to the judgment of triggering switching or reselection according to the ephemeris information of the first satellite, acquiring the ephemeris information of each satellite in at least one adjacent satellite, and determining a target cell in at least one first cell according to the ephemeris information of each satellite in the at least one adjacent satellite; each satellite of the at least one adjacent satellite is an adjacent satellite to the first satellite; any one of the at least one first cell belongs to one of the at least one adjacent satellites; and

A power adjustment module configured to: and adjusting the power of the beam corresponding to the source cell and/or adjusting the power of the beam corresponding to the target cell so that the difference between the power of the beam corresponding to the target cell and the power of the beam corresponding to the source cell meets the condition of triggering handover or reselection.

7. The optimization device for satellite communication according to claim 6, wherein the judgment module is configured to: acquiring the residual service duration of the first satellite relative to the ground position of the terminal and/or the elevation angle of the first satellite relative to the ground position of the terminal according to the ephemeris information of the first satellite and the ground position of the terminal; and triggering switching or reselection in response to the remaining service duration of the first satellite relative to the ground position of the terminal reaching a preset time threshold value and/or the elevation angle of the first satellite relative to the ground position of the terminal being lower than a preset elevation angle threshold value.

8. The optimization device for satellite communication according to claim 6 or 7, wherein the target cell determination module is configured to: acquiring the residual service duration of each first cell in the at least one first cell relative to the ground position of the terminal according to the ephemeris information of each satellite in the at least one adjacent satellite and the ground position of the terminal, and/or the elevation angle of each satellite in the at least one first cell relative to the ground position of the terminal; sorting the first cells in the at least one first cell according to the order of the remaining service duration of the first cells in the at least one first cell from more to less relative to the ground position of the terminal and/or according to the order of the elevation angle of the satellite of the first cells in the at least one first cell from higher to lower relative to the ground position of the terminal; and verifying the availability of each first cell in the at least one first cell according to the sequencing result of each first cell in the at least one first cell, and determining the first cell with the availability and the forefront sequencing in the at least one first cell as the target cell.

9. The optimization device for satellite communication according to claim 7, wherein the power adjustment module comprises:

A first power adjustment unit configured to: acquiring a path loss value of the minimum elevation angle of the first satellite; acquiring a ground-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value; acquiring a target range, wherein the target range is a range which is larger than 0 and smaller than or equal to a first difference value, and the first difference value is a difference value between a path loss value of the minimum elevation angle of the satellite and a ground-air loss value when the elevation angle of the coverage area of the first satellite is a preset elevation angle threshold value; and adjusting the power of a beam corresponding to the source cell into the target range; and/or

A second power adjustment unit configured to: and enhancing the power of a beam corresponding to the target cell in a preset period, and/or reducing the data signal power of the target cell to enhance the reference signal power of the target cell.

10. A computer device comprising a memory and a processor, the memory having stored therein a computer program, which when executed by the processor performs the method of optimizing satellite communication according to any one of claims 1 to 5.

11. A computer-readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, performs the optimization method of satellite communication according to any one of claims 1 to 5.