Dynamic beam hopping based interference avoidance method for user backhaul link

Abstract

The present disclosure provides a dynamic beam hopping based user return link interference avoidance method, which relates to the technical field of satellite communication and aims to meet service requirements and maximize the average service satisfaction of user terminals in the case of avoiding interference. The method comprises: obtaining system parameters, user terminal return service requirements and service requirements; for each user terminal, determining the candidate access satellite of the user terminal in the next scheduling period; under the constraint that the user terminal can only send services to its own candidate access satellite in the next scheduling period, determining the access relationship and beam hopping time plan between the user terminal and the target non-geostationary satellite in the next scheduling period according to the service requirements and the user terminal return service requirements; under the constraint of the access relationship and the beam hopping time plan, determining the user resource allocation scheme with the goal of maximizing the average service satisfaction of multiple user terminals accessed by each target non-geostationary satellite.

Description

Technical Field

[0001] This disclosure relates to the field of satellite communication technology, and in particular to an interference avoidance method for user return links based on dynamic beam hopping. Background Technology

[0002] Non-Geostationary Satellite Orbit (NGSO) constellations offer higher communication capacity, lower signal latency, and stronger signal coverage, leading to their rapid development in recent years. However, with the increasing number of NGSO constellations being declared, spectrum resources are becoming increasingly scarce, making frequency coexistence among NGSO constellations an unavoidable reality. Due to limitations in terminal antenna size, user return links are more likely to cause co-channel interference to other NGSO satellite systems. Therefore, under spectrum coexistence conditions, how NGSO network operators can ensure on-demand transmission of return services while avoiding interference to other NGSO satellite systems is a problem worthy of study. Summary of the Invention

[0003] In view of the above problems, this disclosure provides an interference avoidance method for user return links based on dynamic beam hopping, so as to overcome the above problems or at least partially solve the above problems.

[0004] A first aspect of this disclosure provides an interference avoidance method for user return links based on dynamic beam hopping, the method comprising: In each scheduling cycle, system parameters, user terminal return service requirements, and service requirements are acquired; the system parameters include: position information of each target non-geostationary orbit satellite of the target system, position information of each non-geostationary orbit satellite of other systems, position information of each user terminal of the target system, and interference angle threshold; one scheduling cycle includes multiple beam hopping time slots; For each user terminal, if the angle formed by the line connecting the target non-geostationary orbit satellite to the user terminal and the lines connecting the user terminal to each non-geostationary orbit satellite of the other systems is greater than the interference angle threshold, the target non-geostationary orbit satellite is determined as a candidate access satellite for the user terminal in the next scheduling cycle; wherein, the user terminal transmits services to its own candidate access satellite in the next scheduling cycle to achieve interference avoidance of the user's return link; Under the constraint that the user terminal can only transmit services to its own candidate access satellites in the next scheduling cycle, the access relationship and beam hopping time plan between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle are determined based on the service requirements and the user terminal's return service requirements; the service requirements include at least one or more of the following: balancing satellite load, maximizing cell service satisfaction, minimizing average user terminal latency, and maximizing fairness among user terminals: Under the constraints of the access relationship and the hopping beam time schedule, a user resource allocation scheme is determined with the objective of maximizing the average service satisfaction of multiple user terminals accessed by each of the target non-geostationary orbit satellites. The user resource allocation scheme represents the transmit power of each user terminal to each frequency block of each beam of its access satellite in each hopping beam time slot of the next scheduling cycle; wherein, each frequency block of each beam of the target non-geostationary orbit satellite can only be allocated to one user terminal in one hopping beam time slot. The user resource allocation scheme is sent to each target non-geostationary orbit satellite and each user terminal, so that each user terminal can transmit services according to the user resource allocation scheme, and each target non-geostationary orbit satellite can receive services according to the user resource allocation scheme.

[0005] Optionally, the system parameters further include: channel bandwidth, the maximum number of beams of each target non-geostationary orbit satellite, the number of frequency resource blocks for each beam, and the signal-to-noise ratio of the signals transmitted by each user terminal to each frequency block of each beam of each target non-geostationary orbit satellite in each hop beam time slot. Under the constraints of the access relationship and the beam hopping time schedule, the user resource allocation scheme is determined with the objective of maximizing the average service satisfaction of multiple user terminals accessed by each of the target non-geostationary orbit satellites, including: Solve the following first-constraint optimization problem Determine the user resource allocation scheme:

[0006] in, The average service satisfaction of multiple user terminals accessing the target non-geostationary orbit satellite is represented by C1~C6, which represent the constraints respectively. The transmit power of the u-th user terminal in the i-th frequency block of the k-th beam of the n-th target non-geostationary orbit satellite in the t-th hop beam time slot; This characterizes the transmit power of the u-th user terminal in the t-th beam hop time slot to the i-th frequency block of the k-th beam of the n-th target non-geostationary satellite. =1 represents emission. =0 indicates no emission; This characterizes the service satisfaction level of the u-th user terminal throughout the entire scheduling cycle. The channel capacity of the u-th user terminal in the t-th hop beam time slot of the k-th beam of the n-th target non-geostationary orbit satellite is represented by T, where T represents the scheduling period, I is the number of frequency blocks in the k-th beam, and K is the number of beams. B represents the return service requirement of the u-th user terminal; B represents the channel bandwidth. Defined as the beam skipping decision variable for the nth target non-geostationary orbit satellite. =1 indicates that the nth target non-geostationary satellite illuminates the mth cell it covers in the tth hop beam time slot. =0 indicates that the nth target non-geostationary satellite does not illuminate the mth cell it covers in the tth hop beam time slot; Defined as the access relationship variable between the nth target non-geostationary orbit satellite and the uth user. =0 indicates that the u-th user terminal does not connect to the n-th target non-geostationary orbit satellite. =1 indicates that the u-th user terminal accesses the n-th target non-geostationary orbit satellite; This indicates whether the u-th user terminal is located in the m-th cell. =1 indicates that the u-th user terminal is located in the m-th cell. =0 indicates that the u-th user terminal is not located in the m-th cell; It represents the maximum transmit power of the u-th user terminal; it represents the signal-to-interference-plus-noise ratio.

[0007]

[0008] Optionally, when the service demand is to balance satellite load, determining the access relationship and beam hopping time schedule between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle based on the service demand and the user terminal's return service demand includes: With the objective of minimizing the difference between the load of the target non-geostationary orbit satellite with the highest load and the load of the target non-geostationary orbit satellite with the lowest load, the access satellite for each user terminal is determined from the candidate access satellites for each user terminal in the next scheduling cycle, based on the service requirements of each user terminal; wherein, one user terminal accesses one target non-geostationary orbit satellite, and the load of the target non-geostationary orbit satellite is the total service requirements of the accessing user terminal.

[0009] Optionally, the step of determining the access satellite for each user terminal from the candidate access satellites in the next scheduling cycle, based on the service requirements of each user terminal and with the objective of minimizing the difference between the load of the target non-geostationary orbit satellite with the highest load and the load of the target non-geostationary orbit satellite with the lowest load, includes: Solve the following second-constraint optimization problem Determine the access satellite for each user terminal:

[0010] in, Characterizes the difference between the load of the target non-geostationary orbit satellite with the largest minimum load and the load of the target non-geostationary orbit satellite with the smallest minimum load; ~ Characterize the constraints; Defined as the access relationship variable between the nth target non-geostationary orbit satellite and the uth user. =0 indicates that the u-th user terminal does not connect to the n-th target non-geostationary orbit satellite. =1 indicates that the u-th user terminal accesses the n-th target non-geostationary orbit satellite; Characterizes the payload of the nth target non-geostationary satellite; The u-th user terminal represents the service requirements of the u-th user terminal, and U represents the number of user terminals, u=1,2,……,U; The set of interference representing the nth user terminal; N is the number of target non-geostationary orbit satellites, n=1,2,……,N.

[0011] Optionally, the system parameters may further include: the number of beams, channel bandwidth, and SINR of each of the target non-geostationary orbit satellites; When the service demand is to balance satellite load and maximize service satisfaction in the cell, after determining the access satellite for each user terminal, the method further includes: For each of the target non-geostationary orbit satellites, the target cell where the user terminal accessing the target non-geostationary orbit satellite is located, and the number of the target cells, are determined according to the access relationship. The total service requirements of each target cell are determined by the service requirements of the user terminals accessing the target non-geostationary orbit satellites in each target cell. Based on the channel bandwidth and SINR of the target non-geostationary orbit satellite, Shannon's theorem is used to determine the target channel capacity provided by the target non-geostationary orbit satellite for each target cell in each hop beam slot of the next scheduling cycle. The target channel capacity includes unknown hop beam decision variables, which characterize whether the target non-geostationary orbit satellite illuminates each target cell in each hop beam slot of the next scheduling cycle. Based on the target channel capacity provided by the target non-geostationary satellite for each target cell in each hop beam slot of the next scheduling cycle, and the total service demand of each target cell, the service satisfaction of each target cell in the next scheduling cycle is obtained. When the number of target cells illuminated by the target non-geostationary orbit satellite in each hop beam slot does not exceed the number of beams, the hop beam decision variables are solved with the objective of maximizing the total service satisfaction of the multiple target cells. The total service satisfaction of the multiple target cells is the quotient of the sum of the service satisfaction of each target cell in the next scheduling cycle and the number of target cells. The beam hopping time schedule is determined based on the beam hopping decision variables.

[0012] Optionally, the step of solving the beam hopping decision variables with the objective of maximizing the total service satisfaction of multiple target cells, provided that the number of target cells illuminated by the target non-geostationary satellite in each beam hopping time slot does not exceed the number of beams, includes: Solve the following third-constraint optimization problem Determine the beam hopping decision variables:

[0013] in, This represents maximizing the overall service satisfaction of multiple target cells; ~ Each characterizes a constraint condition; Defined as the beam skipping decision variable for the nth target non-geostationary orbit satellite. =1 indicates that the nth target non-geostationary satellite illuminates the mth target cell it covers in the tth hop beam time slot. =0 indicates that the nth non-geostationary satellite does not illuminate the mth target cell it covers in the t-th hopping beam time slot; M is the number of target cells, m=1,2,...,M; Characterizes the service satisfaction level of the m-th target cell throughout the entire scheduling cycle; Characterizes the channel capacity provided by the nth target non-geostationary orbit satellite in the tth hop beam time slot for the mth target cell it covers; This represents the total service demand of the m-th target cell; The set of target user terminals representing the nth non-geostationary satellite in the mth target cell. B represents the service requirements of the u-th user terminal; B represents the channel bandwidth. The signal-to-interference-plus-noise ratio of the nth target non-geostationary satellite in the t-th hop beam time slot with respect to the mth target cell is represented by T; the scheduling period is represented by K; and the number of beams is represented by K.

[0014] Optionally, the hopping beam timing schedule is: a hopping beam pattern for each hopping beam time slot within a scheduling period, wherein the hopping beam pattern includes: beam pointing, beam frequency, beam bandwidth, and beam transmit power.

[0015] Optionally, the user terminal's backhaul service requirement refers to the bandwidth requirement or service queue length most recently reported by the user terminal through the backhaul link.

[0016] Optionally, sending the user resource allocation scheme to each target non-geostationary orbit satellite and each user terminal includes: The user resource allocation scheme is sent to each target non-geostationary orbit satellite via the uplink feed link, so that the target non-geostationary orbit satellites can transmit the user resource allocation scheme to the user terminal via the downlink user link.

[0017] Optionally, based on the service requirements and the user terminal's return service requirements, the access relationship and beam hopping time schedule between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle are determined, including: A target algorithm is adopted to determine the access relationship and beam hopping time plan between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle based on the service requirements and the user terminal's return service requirements. The target algorithm includes heuristic algorithms, convex optimization algorithms, and machine learning algorithms.

[0018] A second aspect of this disclosure provides an interference avoidance device for a user return link based on dynamic beam hopping, the device comprising: The acquisition module is used to acquire system parameters, user terminal return service requirements, and service requirements in each scheduling cycle. The system parameters include: position information of each target non-geostationary orbit satellite of the target system, position information of each non-geostationary orbit satellite of other systems, position information of each user terminal of the target system, and interference angle threshold. One scheduling cycle includes multiple beam hopping time slots. The first determining module is configured to, for each user terminal, determine the target non-geostationary orbit satellite as a candidate access satellite for the user terminal in the next scheduling cycle if the angle formed by the line connecting the target non-geostationary orbit satellite to the user terminal and the lines connecting the non-geostationary orbit satellites of the other systems to the user terminal is greater than the interference angle threshold. The user terminal then transmits services to its own candidate access satellite in the next scheduling cycle to achieve interference avoidance on the user's return link. The second determining module is used to determine, under the constraint that the user terminal can only transmit services to its own candidate access satellites in the next scheduling cycle, the access relationship and beam hopping time plan between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle, based on the service requirements and the user terminal's return service requirements; the service requirements include at least one or more of the following: balancing satellite load, maximizing cell service satisfaction, minimizing average latency of user terminals, and maximizing fairness among user terminals: The third determining module is used to determine a user resource allocation scheme under the constraints of the access relationship and the hopping beam time schedule, with the objective of maximizing the average service satisfaction of multiple user terminals accessed by each of the target non-geostationary orbit satellites. The user resource allocation scheme represents the transmit power of each user terminal to each frequency block of each beam of its access satellite in each hopping beam time slot of the next scheduling cycle; wherein, each frequency block of each beam of the target non-geostationary orbit satellite can only be allocated to one user terminal in one hopping beam time slot. The transmitting module is used to transmit the user resource allocation scheme to each target non-geostationary orbit satellite and each user terminal, so that each user terminal can transmit services according to the user resource allocation scheme, and each target non-geostationary orbit satellite can receive services according to the user resource allocation scheme.

[0019] A third aspect of this disclosure provides an electronic device, including: a processor; and a memory for storing processor-executable instructions; wherein the processor is configured to execute instructions to implement the interference avoidance method for user return links based on dynamic beam hopping as described in the first aspect.

[0020] A fourth aspect of this disclosure provides a computer-readable storage medium that, when executed by a processor of an electronic device, enables the electronic device to perform an interference avoidance method for a user return link based on dynamic beam hopping, as described in the first aspect.

[0021] The embodiments disclosed herein have the following advantages: In this embodiment, by determining whether the angle between the lines connecting the user terminal to each target non-geostationary orbit satellite and other non-geostationary orbit satellites of other systems is greater than an interference angle threshold, the candidate access satellites for each user terminal in the next scheduling cycle can be determined. The user terminal then transmits services to its own candidate access satellites in the next scheduling cycle, thus achieving interference avoidance on the user's return link. Under the constraint that the user terminal transmits services to its own candidate access satellites in the next scheduling cycle, the determined access relationship and beam hopping time schedule both satisfy interference avoidance. Therefore, interference avoidance can be achieved while fulfilling service requirements. Furthermore, the user resource allocation scheme can be determined with the objective of maximizing the average service satisfaction of multiple user terminals accessed by each of the target non-geostationary orbit satellites. Therefore, interference avoidance is achieved while maximizing the average service satisfaction of user terminals. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments of this disclosure will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a flowchart of the steps of an interference avoidance method for a user return link based on dynamic beam hopping in an embodiment of this disclosure; Figure 2 This is a schematic diagram illustrating the determination of candidate access satellites in an embodiment of this disclosure; Figure 3 This is a schematic diagram illustrating an application scenario of an embodiment of this disclosure. Detailed Implementation

[0024] To make the above-mentioned objectives, features and advantages of this disclosure more apparent and understandable, the disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Given the large number of NGSO satellites and their multi-coverage characteristics, users can simultaneously view multiple satellites, providing greater freedom for satellite access and more options for inter-constellation interference avoidance. Furthermore, leveraging the rapid beamforming capabilities of phased array antennas, users can access satellites on demand and in a time-sharing manner. Simultaneously, facing the rapid changes in network topology caused by the high-speed movement of the NGSO constellation, users can quickly switch between different satellites using beam hopping to select the optimal satellite for interference avoidance. This disclosure, based on the multi-coverage characteristics of NGSO and the flexibility of beam hopping, plans a user satellite access strategy and rationally allocates beam hopping resources to users, achieving interference avoidance and on-demand transmission.

[0026] Reference Figure 1 The diagram illustrates a flowchart of the interference avoidance method for user return links based on dynamic beam hopping, as shown in this embodiment of the present disclosure. Figure 1 As shown, the interference avoidance method for user return links based on dynamic beam hopping can be applied to the operation and control center of the target system, and may specifically include steps S11 to S15.

[0027] Step S11: In each scheduling cycle, obtain system parameters, user terminal return business requirements, and service requirements.

[0028] The system parameters include: position information of each target non-geostationary orbit satellite of the target system, position information of each non-geostationary orbit satellite of other systems, position information of each user terminal of the target system, and interference angle threshold; one scheduling cycle includes multiple hopping beam time slots.

[0029] The target system is the system whose access relationship between non-geostationary orbit satellites and user terminals needs to be determined for the next scheduling cycle. Other systems are any one or more systems different from the target system. To reduce computational load, other systems can be systems whose own satellites collinearly interfere with the target system's satellites. The target non-geostationary orbit satellites are those belonging to the target system, and the user terminals are those belonging to the target system; other non-geostationary orbit satellites are those belonging to other systems.

[0030] The satellite's position information is publicly available, therefore the position information of the target non-geostationary orbit satellites and other non-geostationary orbit satellites can be directly obtained. The target system's operation and control center can directly obtain the position information of each target user terminal.

[0031] The interference angle threshold can be determined in advance based on experience, experiments, etc. If the angle between the lines connecting two non-geostationary satellites and a user terminal is less than the interference angle threshold, then the inter-beam interference between the two non-geostationary satellites will be significant.

[0032] The user terminal backhaul service requirement refers to the bandwidth requirement or service queue length most recently reported by the user terminal through the backhaul link.

[0033] Step S12: For each user terminal, if the angle formed by the line connecting the target non-geostationary orbit satellite to the user terminal and the lines connecting each non-geostationary orbit satellite of the other system to the user terminal is greater than the interference angle threshold, the target non-geostationary orbit satellite is determined as a candidate access satellite for the user terminal in the next scheduling cycle.

[0034] In this process, the user terminal transmits services to its candidate access satellites in the next scheduling cycle to avoid interference on the user's return link.

[0035] Based on the location information of the user terminal and the location information of the target non-geostationary orbit satellite, the connection between the user terminal and the target non-geostationary orbit satellite can be determined; based on the location information of the user terminal and the location information of non-geostationary orbit satellites of other systems, the connection between the user terminal and non-geostationary orbit satellites of other systems can be determined.

[0036] If the angle between the line connecting a user terminal to a target non-geostationary orbit satellite and the line connecting the user terminal to any other system's non-geostationary orbit satellite is less than the interference angle threshold, then interference may occur when the user terminal transmits services to the target non-geostationary orbit satellite.

[0037] If the angle formed by the line connecting a user terminal to a target non-geostationary orbit satellite and the line connecting the user terminal to any other system's non-geostationary orbit satellite is greater than the interference angle threshold, then the user terminal can transmit services to the target non-geostationary orbit satellite with minimal or no interference. Therefore, the target non-geostationary orbit satellite can be identified as a candidate access satellite for the user terminal in the next scheduling cycle. A user terminal may have multiple candidate access satellites, but a user terminal will only transmit services to one satellite within a scheduling cycle. Therefore, regardless of which candidate access satellite the user terminal selects as the access satellite for the next scheduling cycle, interference avoidance can be achieved.

[0038] Figure 2 This is a schematic diagram illustrating the determination of candidate access satellites in this embodiment of the disclosure. The angle formed by the line connecting the system terminal to the system satellite and the line connecting the system terminal to other system satellites is greater than the interference angle threshold. If the satellite of this system is selected, then it is a candidate access satellite for the terminal of this system. Here, the terminal of this system refers to the user terminal, the satellite of this system refers to the target non-geostationary orbit satellite, and the satellites of other systems refer to the non-geostationary orbit satellites of other systems.

[0039] The method described above, which compares the included angle of the connecting lines with an interference angle threshold to determine candidate access satellites for a user terminal, can be called a beam angle isolation strategy. Optionally, methods including, but not limited to, progressive elevation strategies and beam power control strategies can also be used to determine candidate access satellites for the user terminal in the next scheduling cycle. The progressive elevation strategy can adjust the attitude angle of the non-geostationary orbit satellite to shift the overall coverage area of ​​the non-geostationary orbit satellite, thereby avoiding collinear interference. The beam power control strategy can obtain the interference threshold for the user terminal and adjust the beam power of the non-geostationary orbit satellite to be lower than the interference threshold used for the terminal, thus achieving interference avoidance.

[0040] Step S13: Under the constraint that the user terminal can only send services to its own candidate access satellite in the next scheduling cycle, the access relationship and beam hopping time plan between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle are determined according to the service requirements and the user terminal's return service requirements.

[0041] The service requirements include at least one or more of the following: balancing satellite load, maximizing service satisfaction in the cell, minimizing average latency of user terminals, and maximizing fairness among user terminals.

[0042] Under the constraint that a user terminal can only transmit services to its own candidate access satellites in the next scheduling cycle, the access relationship and beam hopping time plan between the user terminal and the target non-geostationary orbit satellite can be further determined. Determining the access relationship between the user terminal and the target non-geostationary orbit satellite means: when there are multiple candidate access satellites for the user terminal, determining the target non-geostationary orbit satellite for the user terminal to access in the next scheduling cycle from among the multiple candidate access satellites.

[0043] A hopping beam time schedule is a hopping beam pattern for each hopping beam slot within a scheduling period; the hopping beam pattern includes: beam pointing, beam frequency, beam bandwidth, and beam transmit power; a scheduling period includes multiple hopping beam slots, such as dozens or hundreds; a hopping beam slot represents the shortest dwell time of the beam in the cell.

[0044] Different service requirements may arise under different circumstances. Based on these different service requirements, different access relationships and beam hopping time schedules can be determined to meet service requirements while achieving interference avoidance. Service requirements may include, but are not limited to, any one or more of the following: balancing satellite load, maximizing service satisfaction in the cell, minimizing average latency of user terminals, maximizing fairness among user terminals, minimizing the difference between service supply and demand in the cell, and maximizing service throughput.

[0045] When service requirements differ, access relationships and beam hopping schedules can be determined by solving different constrained optimization problems. Optionally, different objective algorithms can be used to determine access relationships and beam hopping schedules based on service requirements and user terminal reverse business requirements. Objective algorithms include, but are not limited to, heuristic algorithms, convex optimization algorithms, and machine learning algorithms. The specific implementation methods of each algorithm can be found in relevant technologies.

[0046] Step S14: Under the constraints of the access relationship and the beam hopping time plan, determine the user resource allocation scheme with the objective of maximizing the average service satisfaction of multiple user terminals accessed by each of the target non-geostationary orbit satellites.

[0047] The user resource allocation scheme represents the transmit power of the user terminal to each frequency block of each beam of its access satellite in each hop beam time slot of the next scheduling cycle; wherein, each frequency block of each beam of the target non-geostationary orbit satellite can only be allocated to one user terminal in one hop beam time slot.

[0048] Under the constraints of access relationships and beam hopping time schedules, the target non-geostationary orbit satellites that each user terminal will access in the next scheduling cycle can be determined, as well as the cells illuminated by each beam of each target non-geostationary orbit satellite in each beam hopping time slot of the next scheduling cycle.

[0049] When a user terminal is illuminated by the beam of a target non-geostationary orbit satellite it is connected to, it can transmit signals to various frequency blocks of that beam. A beam has multiple frequency blocks, and when a user terminal transmits signals to frequency blocks, it can determine which frequency blocks it should transmit to and the transmission power based on different needs. If a user terminal does not transmit to a frequency block, it can be considered that the power of the transmitted signal to that frequency block is 0.

[0050] When determining the user resource allocation scheme, constraints are imposed on two aspects: access relationships and beam hopping time schedules. These constraints are further compounded by other relevant limitations. By addressing these multiple constraints, a user resource allocation scheme that maximizes the average service satisfaction of multiple user terminals accessed by each target non-geostationary orbit satellite can be derived. These limitations include, but are not limited to: each frequency block of each beam of the target non-geostationary orbit satellite can only be allocated to one user terminal in a beam hopping time slot; the transmit power of a user terminal in each frequency block cannot exceed the maximum transmit power of all terminals within that user group; and the transmit power of a user terminal in a beam hopping time slot cannot exceed the maximum transmit power of all terminals within that user group. The user resource allocation scheme can be determined using, but is not limited to, heuristic algorithms, convex optimization algorithms, and machine learning algorithms, under the constraints of access relationships and beam hopping time schedules, with the objective of maximizing the average service satisfaction of multiple user terminals accessed by each target non-geostationary orbit satellite.

[0051] Step S15: Send the user resource allocation scheme to each target non-geostationary orbit satellite and each user terminal.

[0052] Sending the user resource allocation scheme to each target non-geostationary orbit satellite and each user terminal enables each user terminal to transmit services according to the user resource allocation scheme, and enables each target non-geostationary orbit satellite to receive services according to the user resource allocation scheme.

[0053] After the user resource allocation scheme is determined, it can be sent to each target non-geostationary orbit satellite via the uplink feeder link. The target non-geostationary orbit satellites then transmit the user resource allocation scheme to the user terminal via the downlink user link.

[0054] By employing the technical solution of this disclosure, the candidate access satellites for each user terminal in the next scheduling cycle can be determined based on whether the angle between the lines connecting the user terminal and each target non-geostationary orbit satellite and each non-geostationary orbit satellite of other systems is greater than an interference angle threshold. The user terminal then transmits services to its own candidate access satellites in the next scheduling cycle, thus achieving interference avoidance of the user's return link. Under the constraint that the user terminal transmits services to its own candidate access satellites in the next scheduling cycle, the determined access relationship and beam hopping time schedule both satisfy interference avoidance. Therefore, interference avoidance can be achieved while fulfilling service requirements. Furthermore, the user resource allocation scheme can be determined with the objective of maximizing the average service satisfaction of multiple user terminals accessed by each of the target non-geostationary orbit satellites. Therefore, interference avoidance is achieved while maximizing the average service satisfaction of user terminals.

[0055] Alternatively, based on the above technical solution, the following first-constraint optimization problem can be solved. This allows us to determine a user resource allocation scheme that maximizes the average service satisfaction of multiple user terminals accessing each target non-geostationary orbit satellite, under the constraints of access relationships and beam hopping time schedules.

[0056]

[0057] in, The average service satisfaction of multiple user terminals accessing the target non-geostationary orbit satellite is represented by C1~C6, which represent the constraints respectively. The transmit power of the u-th user terminal in the i-th frequency block of the k-th beam of the n-th target non-geostationary orbit satellite in the t-th hop beam time slot; This characterizes the transmit power of the u-th user terminal in the t-th beam hop time slot to the i-th frequency block of the k-th beam of the n-th target non-geostationary satellite. =1 represents emission. =0 indicates no emission; This characterizes the service satisfaction level of the u-th user terminal throughout the entire scheduling cycle. The channel capacity of the u-th user terminal in the t-th hop beam time slot of the k-th beam of the n-th target non-geostationary orbit satellite is represented by T, where T represents the scheduling period, I is the number of frequency blocks in the k-th beam, and K is the number of beams. B represents the return service requirement of the u-th user terminal; B represents the channel bandwidth. Defined as the beam skipping decision variable for the nth target non-geostationary orbit satellite. =1 indicates that the nth target non-geostationary satellite illuminates the mth cell it covers in the tth hop beam time slot. =0 indicates that the nth target non-geostationary satellite does not illuminate the mth cell it covers in the tth hop beam time slot; Defined as the access relationship variable between the nth target non-geostationary orbit satellite and the uth user. =0 indicates that the u-th user terminal does not connect to the n-th target non-geostationary orbit satellite. =1 indicates that the u-th user terminal accesses the n-th target non-geostationary orbit satellite; This indicates whether the u-th user terminal is located in the m-th cell. =1 indicates that the u-th user terminal is located in the m-th cell. =0 indicates that the u-th user terminal is not located in the m-th cell; It represents the maximum transmit power of the u-th user terminal; it represents the signal-to-interference-plus-noise ratio.

[0058]

[0059] in, This means that the user terminal can only send signals when it is illuminated by the beam of the accessed satellite; This means that only one user terminal can be assigned to each frequency block of each beam. and This indicates the power constraint of the user terminal.

[0060] Optionally, based on the above technical solution, as an embodiment, when the service demand is to balance satellite load, the step of determining the access relationship and beam hopping time plan between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle according to the service demand and the user terminal's return service demand may include: taking the goal of minimizing the difference between the load of the target non-geostationary orbit satellite with the largest load and the load of the target non-geostationary orbit satellite with the smallest load, and determining the access satellite for each user terminal from the candidate access satellites for each user terminal in the next scheduling cycle according to the service demand of each user terminal; wherein, one user terminal accesses one target non-geostationary orbit satellite, and the load of the target non-geostationary orbit satellite is the total service demand of the accessing user terminal.

[0061] Alternatively, the objective may be to minimize the difference between the load of the target non-geostationary orbit satellite with the highest load and the load of the target non-geostationary orbit satellite with the lowest load, and to determine the access satellite for each user terminal from the candidate access satellites for each user terminal in the next scheduling cycle, based on the service requirements of each target user terminal.

[0062] The following second-constraint optimization problem can be solved. This enables the determination of the access satellite for each user terminal from the candidate access satellites in the next scheduling cycle, while balancing the load of each first non-geostationary orbit satellite.

[0063]

[0064] in, Characterizes the difference between the load of the target non-geostationary orbit satellite with the largest minimum load and the load of the target non-geostationary orbit satellite with the smallest minimum load; The load of the nth target non-geostationary orbit satellite is the sum of the service demands of each user terminal connected to the target non-geostationary orbit satellite; The interference avoidance constraint is defined as follows: if the nth target non-geostationary orbit satellite is in the interference set of the uth user terminal, then the uth user terminal cannot access the nth target non-geostationary orbit satellite. This indicates that a user terminal can only access one target non-geostationary orbit satellite. Defined as the access relationship variable between the nth target non-geostationary orbit satellite and the uth user. =0 indicates that the u-th user terminal does not connect to the n-th target non-geostationary orbit satellite. =1 indicates that the u-th user terminal accesses the n-th target non-geostationary orbit satellite; Characterizes the payload of the nth target non-geostationary satellite; The u-th user terminal represents the service requirements of the u-th user terminal, and U represents the number of user terminals, u=1,2,……,U; The set of interference representing the nth user terminal; N is the number of target non-geostationary orbit satellites, n=1,2,……,N.

[0065] If a target non-geostationary orbit satellite is not a candidate access satellite for a user terminal, then the target non-geostationary orbit satellite is a satellite in the interference set of that user terminal. The number of user terminals, the number of target non-geostationary orbit satellites, etc., are system parameters that can be obtained by the operations control center.

[0066] After the access relationship is determined, the access relationship is sent to each target non-geostationary orbit satellite via the uplink feeder link, and the target non-geostationary orbit satellite transmits the access relationship to the user terminal via the downlink user link.

[0067] As an example, after determining the target non-geostationary orbit satellite served by each user terminal in the next scheduling cycle, the beam hopping time plan of the target non-geostationary orbit satellite can also be determined while maximizing the total service satisfaction of each cell served by each target non-geostationary orbit satellite. The beam hopping time plan is the beam hopping pattern for each beam hopping time slot within a scheduling cycle; the beam hopping pattern includes: beam pointing, beam frequency, beam bandwidth, and beam transmission power; a scheduling cycle includes multiple beam hopping time slots, such as dozens or hundreds; the beam hopping time slot represents the shortest dwell time of the beam in the cell. Specifically, determining the beam hopping time plan of the target non-geostationary orbit satellite may include steps S21 to S26: Step S21: For each of the target non-geostationary orbit satellites, determine the target cell where the user terminal accessing the target non-geostationary orbit satellite is located, and the number of the target cells, based on the access relationship.

[0068] The cell where the user terminal accessing the target non-geostationary orbit satellite is located is identified as the target cell, and the number of target cells corresponding to each target non-geostationary orbit satellite can then be obtained.

[0069] Step S22: Determine the total service requirements of each target cell by considering the service requirements of the user terminals accessing the target non-geostationary satellites in each target cell.

[0070] The sum of the service demands of user terminals accessing the target non-geostationary satellite in each target cell is the total service demand for each target cell.

[0071] Step S23: Based on the channel bandwidth and SINR of the target non-geostationary orbit satellite, and the number of hop beam slots included in the next scheduling period, Shannon's theorem is used to determine the target channel capacity provided by the target non-geostationary orbit satellite for each target cell in each hop beam slot of the next scheduling period. The target channel capacity includes unknown hop beam decision variables, which characterize whether the target non-geostationary orbit satellite illuminates each target cell in each hop beam slot of the next scheduling period.

[0072] The number of beams, channel bandwidth, and SINR (Signal to Interference plus Noise Ratio) for each target non-geostationary satellite, as well as the number of hopping beam slots included in the next scheduling cycle, are all system parameters that can be obtained by the operations control center. SINR refers to the ratio of the strength of the received useful signal to the strength of the received interference signal (noise and interference).

[0073] Using Shannon's theorem, based on the channel bandwidth, SINR, number of hop beam slots in the next scheduling period of the target non-geostationary orbit satellite, and whether each hop beam slot of the target non-geostationary orbit satellite illuminates the target cell in the next scheduling period, the target channel capacity provided by each hop beam slot of the target non-geostationary orbit satellite for the target cell in the next scheduling period can be calculated. In this embodiment, the hop beam decision variable is used to characterize whether each hop beam slot of the target non-geostationary orbit satellite illuminates each target cell in the next scheduling period.

[0074] Once the beam-hopping decision variables are solved, the beam-hopping time schedule can be determined. However, since the beam-hopping decision variables are unknown at this point, it is impossible to accurately calculate the target channel capacity provided by the target non-geostationary satellite for the target cell in each beam-hopping time slot of the next scheduling cycle. Nevertheless, based on mathematical knowledge, the target channel capacity, including the unknown beam-hopping decision variables, can be determined.

[0075] Step S24: Based on the target channel capacity provided by the target non-geostationary orbit satellite for each target cell in each hop beam slot of the next scheduling cycle, and the total service demand of each target cell, obtain the service satisfaction of each target cell in the next scheduling cycle.

[0076] The service satisfaction of a target cell is the ratio of the total channel capacity provided by the target non-geostationary orbit satellite to the total service demand of the target cell. Based on the target channel capacity provided by the target non-geostationary orbit satellite for each beam hop time slot in the next scheduling cycle, the total channel capacity provided by the target non-geostationary orbit satellite for the target cell in the next scheduling cycle can be determined. It is understandable that because the target channel capacity at this point includes unknown beam hop decision variables, the determined total channel capacity also includes unknown beam hop decision variables.

[0077] Step S25: When the number of target cells illuminated by the target non-geostationary orbit satellite in each hop beam time slot does not exceed the number of beams, the hop beam decision variables are solved with the objective of maximizing the total service satisfaction of the multiple target cells. The total service satisfaction of the multiple target cells is the quotient of the sum of the service satisfaction of each target cell in the next scheduling cycle and the number of target cells.

[0078] One beam of a target non-geostationary orbit satellite can illuminate one cell. Therefore, in each beam hop time slot, the number of target cells illuminated by the target non-geostationary orbit satellite does not exceed the number of beams of the target non-geostationary orbit satellite.

[0079] The total service satisfaction of multiple target cells in the next scheduling cycle is the quotient obtained by dividing the sum of the service satisfaction of each target cell in the next scheduling cycle by the number of target cells. The service satisfaction of each target cell in the next scheduling cycle is a value carrying unknown beam hopping decision variables. Therefore, the total service satisfaction of multiple target cells carrying unknown beam hopping decision variables in the next scheduling cycle can be determined.

[0080] By taking the constraint that the number of target cells illuminated by the non-geostationary orbit satellite in each hop beam slot does not exceed the number of beams of the non-geostationary orbit satellite, the total service satisfaction of multiple target cells can be solved, and the hop beam decision variables can be solved.

[0081] Step S26: Determine the beam hopping time schedule based on the beam hopping decision variables.

[0082] After determining the beam hopping decision variables, the beam hopping time plan for the next scheduling cycle can be determined. It is understood that the beam hopping time plan includes information such as beam pointing; therefore, the beam hopping time plan for the next scheduling cycle includes the service relationship between each target non-geostationary orbit satellite and each user terminal in the next scheduling cycle.

[0083] Furthermore, when sending the user resource allocation scheme to each target non-geostationary orbit satellite and each user terminal, the beam hopping time plan can be sent to each target non-geostationary orbit satellite and each user terminal at the same time, so that each target non-geostationary orbit satellite can transmit services according to the beam hopping time plan, and each user terminal can receive services according to the beam hopping time plan.

[0084] Reference Figure 3 Sending the hopping beam timing plan to each target non-geostationary orbit satellite and each user terminal means that the ground station connected to the operation and control center transmits the hopping beam timing plan to each target non-geostationary orbit satellite through the uplink feeder link, and the target non-geostationary orbit satellite transmits the hopping beam timing plan to each target non-geostationary orbit satellite through the downlink user link.

[0085] By employing the technical solution of this disclosure, since the target user terminals for each target non-geostationary orbit satellite have been determined, interference avoidance can be guaranteed. The beam hopping decision variables are solved with the objective of maximizing the total service satisfaction of multiple target cells; therefore, maximizing the total service satisfaction of multiple target cells can be achieved while simultaneously achieving interference avoidance.

[0086] Optionally, based on the above technical solution, the beam hopping decision variables can be solved with the objective of maximizing the average of the total service satisfaction of multiple target cells.

[0087] Alternatively, based on the above technical solution, the following third-constraint optimization problem can be solved. This allows us to solve for the beam hopping decision variables while ensuring that the number of target cells illuminated by the non-geostationary satellite in each beam hopping time slot does not exceed the number of beams, with the goal of maximizing the total service satisfaction of multiple target cells.

[0088]

[0089] in, This represents maximizing the overall service satisfaction of multiple target cells; The service satisfaction of the m-th target cell during the entire scheduling period is the ratio of the total channel capacity provided by the n-th target non-geostationary satellite to the target cell in each time slot of the scheduling period to the total service demand of the target cell. The total service demand of the m-th target cell is the sum of the service demands of all target user terminals within that target cell; The channel capacity provided by the nth target non-geostationary orbit satellite in the tth hop beam time slot for the mth target cell it covers is represented by Shannon's theorem. The number of target cells that the nth non-geostationary satellite can illuminate in each hop beam time slot does not exceed the number of beams; Defined as the beam skipping decision variable for the nth target non-geostationary orbit satellite. =1 indicates that the nth target non-geostationary satellite illuminates the mth target cell it covers in the tth hop beam time slot. =0 indicates that the nth non-geostationary satellite does not illuminate the mth target cell it covers in the t-th hopping beam time slot; M is the number of target cells, m=1,2,...,M; Characterizes the service satisfaction level of the m-th target cell throughout the entire scheduling cycle; Characterizes the channel capacity provided by the nth target non-geostationary orbit satellite in the tth hop beam time slot for the mth target cell it covers; This represents the total service demand of the m-th target cell; The set of target user terminals representing the nth non-geostationary satellite in the mth target cell. B represents the service requirements of the u-th user terminal; B represents the channel bandwidth. The signal-to-interference-plus-noise ratio of the nth target non-geostationary satellite in the t-th hop beam time slot with respect to the mth target cell is represented by T; the scheduling period is represented by K; the meaning of the remaining characters can be found in the previous text.

[0090] It should be noted that, for the sake of simplicity, the method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of this disclosure are not limited to the described order of actions, because according to the embodiments of this disclosure, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of this disclosure.

[0091] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0092] Those skilled in the art will understand that embodiments of this disclosure can be provided as methods, apparatus, or computer program products. Therefore, embodiments of this disclosure can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, embodiments of this disclosure can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0093] This disclosure describes embodiments of methods, apparatus, electronic devices, and computer program products according to embodiments of this disclosure with reference to flowchart illustrations and / or block diagrams. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0094] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0095] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0096] While preferred embodiments of the present disclosure have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the present disclosure.

[0097] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes the element.

[0098] The interference avoidance method for user return links based on dynamic beam hopping provided in this disclosure has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this disclosure. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this disclosure. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this disclosure. Therefore, the content of this specification should not be construed as a limitation of this disclosure.

Claims

1. An interference avoidance method for user return links based on dynamic beam hopping, characterized in that, The method includes: In each scheduling cycle, system parameters, user terminal return service requirements, and service requirements are acquired; the system parameters include: position information of each target non-geostationary orbit satellite of the target system, position information of each non-geostationary orbit satellite of other systems, position information of each user terminal of the target system, and interference angle threshold; one scheduling cycle includes multiple beam hopping time slots; For each user terminal, if the angle formed by the line connecting the target non-geostationary orbit satellite to the user terminal and the lines connecting the user terminal to each non-geostationary orbit satellite of the other systems is greater than the interference angle threshold, the target non-geostationary orbit satellite is determined as a candidate access satellite for the user terminal in the next scheduling cycle; wherein, the user terminal transmits services to its own candidate access satellite in the next scheduling cycle to achieve interference avoidance of the user's return link; Under the constraint that the user terminal can only transmit services to its own candidate access satellites in the next scheduling cycle, the access relationship and beam hopping time plan between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle are determined based on the service requirements and the user terminal's return service requirements; the service requirements include at least one or more of the following: balancing satellite load, maximizing cell service satisfaction, minimizing average user terminal latency, and maximizing fairness among user terminals: Under the constraints of the access relationship and the hopping beam time schedule, a user resource allocation scheme is determined with the objective of maximizing the average service satisfaction of multiple user terminals accessed by each of the target non-geostationary orbit satellites. The user resource allocation scheme represents the transmit power of each user terminal to each frequency block of each beam of its access satellite in each hopping beam time slot of the next scheduling cycle; wherein, each frequency block of each beam of the target non-geostationary orbit satellite can only be allocated to one user terminal in one hopping beam time slot. The user resource allocation scheme is sent to each target non-geostationary orbit satellite and each user terminal, so that each user terminal can transmit services according to the user resource allocation scheme, and each target non-geostationary orbit satellite can receive services according to the user resource allocation scheme.

2. The method according to claim 1, characterized in that, The system parameters also include: channel bandwidth, the maximum number of beams for each target non-geostationary orbit satellite, the number of frequency resource blocks for each beam, and the signal-to-noise ratio of the signals transmitted by each user terminal to each frequency block of each beam of each target non-geostationary orbit satellite in each hop beam time slot. Under the constraints of the access relationship and the beam hopping time schedule, the user resource allocation scheme is determined with the objective of maximizing the average service satisfaction of multiple user terminals accessed by each of the target non-geostationary orbit satellites, including: Solve the following first-constraint optimization problem Determine the user resource allocation scheme: in, The average service satisfaction of multiple user terminals accessing the target non-geostationary orbit satellite is represented by C1~C6, which represent the constraints respectively. The transmit power of the u-th user terminal in the i-th frequency block of the k-th beam of the n-th target non-geostationary orbit satellite in the t-th hop beam time slot; This characterizes the transmit power of the u-th user terminal in the t-th beam hop time slot to the i-th frequency block of the k-th beam of the n-th target non-geostationary satellite. =1 represents emission. =0 indicates no emission; This characterizes the service satisfaction level of the u-th user terminal throughout the entire scheduling cycle. The channel capacity of the u-th user terminal in the t-th hop beam time slot of the k-th beam of the n-th target non-geostationary orbit satellite is represented by T, where T represents the scheduling period, I is the number of frequency blocks in the k-th beam, and K is the number of beams. B represents the return service requirement of the u-th user terminal; B represents the channel bandwidth. Defined as the beam skipping decision variable for the nth target non-geostationary orbit satellite. =1 indicates that the nth target non-geostationary satellite illuminates the mth cell it covers in the tth hop beam time slot. =0 indicates that the nth target non-geostationary satellite does not illuminate the mth cell it covers in the tth hop beam time slot; Defined as the access relationship variable between the nth target non-geostationary orbit satellite and the uth user. =0 indicates that the u-th user terminal does not connect to the n-th target non-geostationary orbit satellite. =1 indicates that the u-th user terminal accesses the n-th target non-geostationary orbit satellite; This indicates whether the u-th user terminal is located in the m-th cell. =1 indicates that the u-th user terminal is located in the m-th cell. =0 indicates that the u-th user terminal is not located in the m-th cell; Characterizes the maximum transmit power of the u-th user terminal; Characterizes the ratio of signal to interference plus noise.

3. The method according to claim 1, characterized in that, When the service demand is to balance satellite load, determining the access relationship and beam hopping time schedule between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle based on the service demand and the user terminal's return service demand includes: With the objective of minimizing the difference between the load of the target non-geostationary orbit satellite with the highest load and the load of the target non-geostationary orbit satellite with the lowest load, the access satellite for each user terminal is determined from the candidate access satellites for each user terminal in the next scheduling cycle, based on the service requirements of each user terminal; wherein, one user terminal accesses one target non-geostationary orbit satellite, and the load of the target non-geostationary orbit satellite is the total service requirements of the accessing user terminal.

4. The method according to claim 3, characterized in that, The objective is to minimize the difference between the load of the target non-geostationary orbit satellite with the highest load and the load of the target non-geostationary orbit satellite with the lowest load. Based on the service requirements of each user terminal, the method determines the access satellite for each user terminal from the candidate access satellites for the next scheduling cycle, including: Solve the following second-constraint optimization problem Determine the access satellite for each user terminal: in, Characterizes the difference between the load of the target non-geostationary orbit satellite with the largest minimum load and the load of the target non-geostationary orbit satellite with the smallest minimum load; ~ Characterize the constraints; Defined as the access relationship variable between the nth target non-geostationary orbit satellite and the uth user. =0 indicates that the u-th user terminal does not connect to the n-th target non-geostationary orbit satellite. =1 indicates that the u-th user terminal accesses the n-th target non-geostationary orbit satellite; Characterizes the payload of the nth target non-geostationary satellite; The u-th user terminal represents the service requirements of the u-th user terminal, and U represents the number of user terminals, u=1,2,……,U; The set of interference representing the nth user terminal; N is the number of target non-geostationary orbit satellites, n=1,2,……,N.

5. The method according to claim 3, characterized in that, The system parameters also include: the number of beams, channel bandwidth, and SINR for each of the target non-geostationary orbit satellites; When the service demand is to balance satellite load and maximize service satisfaction in the cell, after determining the access satellite for each user terminal, the method further includes: For each of the target non-geostationary orbit satellites, the target cell where the user terminal accessing the target non-geostationary orbit satellite is located, and the number of the target cells, are determined according to the access relationship. The total service requirements of each target cell are determined by the service requirements of the user terminals accessing the target non-geostationary orbit satellites in each target cell. Based on the channel bandwidth and SINR of the target non-geostationary orbit satellite, Shannon's theorem is used to determine the target channel capacity provided by the target non-geostationary orbit satellite for each target cell in each hop beam slot of the next scheduling cycle. The target channel capacity includes unknown hop beam decision variables, which characterize whether the target non-geostationary orbit satellite illuminates each target cell in each hop beam slot of the next scheduling cycle. Based on the target channel capacity provided by the target non-geostationary satellite for each target cell in each hop beam slot of the next scheduling cycle, and the total service demand of each target cell, the service satisfaction of each target cell in the next scheduling cycle is obtained. When the number of target cells illuminated by the target non-geostationary orbit satellite in each hop beam slot does not exceed the number of beams, the hop beam decision variables are solved with the objective of maximizing the total service satisfaction of the multiple target cells. The total service satisfaction of the multiple target cells is the quotient of the sum of the service satisfaction of each target cell in the next scheduling cycle and the number of target cells. The beam hopping time schedule is determined based on the beam hopping decision variables.

6. The method according to claim 5, characterized in that, The method for solving the beam hopping decision variables, with the objective of maximizing the total service satisfaction of multiple target cells, under the condition that the number of target cells illuminated by the target non-geostationary satellite in each beam hopping time slot does not exceed the number of beams, includes: Solve the following third-constraint optimization problem Determine the beam hopping decision variables: in, This represents maximizing the overall service satisfaction of multiple target cells; ~ Each characterizes a constraint condition; Defined as the beam skipping decision variable for the nth target non-geostationary orbit satellite. =1 indicates that the nth target non-geostationary satellite illuminates the mth target cell it covers in the tth hop beam time slot. =0 indicates that the nth non-geostationary satellite does not illuminate the mth target cell it covers in the t-th hopping beam time slot; M is the number of target cells, m=1,2,...,M; Characterizes the service satisfaction level of the m-th target cell throughout the entire scheduling cycle; Characterizes the channel capacity provided by the nth target non-geostationary orbit satellite in the tth hop beam time slot for the mth target cell it covers; This represents the total service demand of the m-th target cell; The set of target user terminals representing the nth non-geostationary satellite in the mth target cell. B represents the service requirements of the u-th user terminal; B represents the channel bandwidth. The signal-to-interference-plus-noise ratio of the nth target non-geostationary satellite in the t-th hop beam time slot with respect to the mth target cell is represented by T; the scheduling period is represented by K; and the number of beams is represented by K.

7. The method according to claim 1, characterized in that, The hopping beam timing schedule is: the hopping beam pattern for each hopping beam time slot within a scheduling period, and the hopping beam pattern includes: beam pointing, beam frequency, beam bandwidth and beam transmission power.

8. The method according to claim 1, characterized in that, The user terminal backhaul service requirement refers to the bandwidth requirement or service queue length most recently reported by the user terminal through the backhaul link.

9. The method according to claim 1, characterized in that, Sending the user resource allocation scheme to each target non-geostationary orbit satellite and each user terminal includes: The user resource allocation scheme is sent to each target non-geostationary orbit satellite via the uplink feed link, so that the target non-geostationary orbit satellites can transmit the user resource allocation scheme to the user terminal via the downlink user link.

10. The method according to claim 1, characterized in that, Based on the service requirements and the user terminal's return service requirements, determine the access relationship and beam hopping time schedule between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle, including: A target algorithm is adopted to determine the access relationship and beam hopping time plan between the user terminal and the target non-geostationary orbit satellite in the next scheduling cycle based on the service requirements and the user terminal's return service requirements. The target algorithm includes heuristic algorithms, convex optimization algorithms, and machine learning algorithms.

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