Method and system for dynamic allocation of resources for multi-beam low earth orbit satellite uplink communication

Abstract

The application discloses a kind of multi-beam low-orbit satellite uplink communication resource dynamic allocation method and system, the method includes: user management unit senses user access satellite communication network, and sends resource request to uplink resource allocation unit;Uplink resource allocation unit receives resource request, and allocates uplink beam, time slot and channel resource for user, and sends resource allocation result to user management unit and star transmission unit respectively, and user management unit sends the resource allocation result received to user;Star transmission unit is scheduled according to resource allocation result, and specified beam receives the uplink data of user in specified channel and specified time slot.The application has higher resource utilization, supports multiple users on-demand dynamic scheduling satellite uplink beam resource.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of satellite communication, in particular to a resource dynamic allocation method and system for multi-beam low-orbit satellite uplink communication. BACKGROUND

[0002] In a multi-beam satellite communication system, each satellite carries multiple beams, which cover different areas on the ground respectively, and these beams together complete the coverage of the ground visible area of a single satellite. Figure 1 is a typical multi-beam low-orbit satellite communication system schematic diagram, mainly composed of three parts of ground gateway station, low-orbit satellite constellation and user. The ground gateway station is the control and management center of the satellite communication system, manages and controls the entire satellite network, and communicates with the satellite through the feeder link; the low-orbit satellite constellation is composed of a plurality of low-orbit satellites distributed in different orbits connected by inter-satellite links, and has wide area coverage capability; the user is a satellite terminal for mutual communication using satellite resources, and the users realize information intercommunication through the inter-satellite link and the inter-satellite link, and the user sends data to the satellite system through the uplink, and the satellite system accurately and efficiently forwards the user data to the destination user through the downlink. The low-orbit satellite moves at high speed relative to the ground according to its preset orbit, and is configured with a multi-beam antenna, and the coverage area corresponding to a single beam is called a beam position, and the ground area covered by the satellite is called a ground coverage area, which is composed of a plurality of beam positions. The satellite can flexibly schedule the multi-beam resources as needed, so that each beam covers a specified beam position, each beam is relatively independent and has a certain bandwidth resource, and each beam can only point to one beam position at the same time, but multiple beams can cover different beam positions or the same beam position. During the movement of the mobile user, the high-speed movement of the low-orbit satellite relative to the low-orbit satellite can easily cause dynamic changes in the coverage area, and the beam position switching and satellite switching are needed to ensure the whole process communication of the service. The data sending capacity of the user is proportional to the antenna aperture and power amplifier configured by it, and the larger the power amplifier and antenna aperture, the greater the sending rate that can be supported, and the maximum sending rate supported is called the uplink rate limit.

[0003] The satellite uplink communication resource structure based on MF-TDMA (Multi Frequency Time-Division Multiple Access) is as follows Figure 2As shown, all frequency resources are divided into multiple orthogonal frequency channels in the frequency domain, and multiple time slots are divided in the time domain with time frames as the cycle structure, and each time-frequency two-dimensional grid is the basic unit of channel resources. The resource dynamic allocation of multi-beam low-orbit satellite uplink communication mainly faces two technical difficulties. On the one hand, compared with the traditional MF-TDMA, multi-beam low-orbit satellite uplink communication introduces beam resources on the basis of its two-dimensional resource structure, and the system schedulable resources are more abundant, the two-dimensional resource allocation of frequency and time slot rises to the three-dimensional resource optimization scheduling problem of beam, frequency and time slot, the beam resources and time-frequency resources are mutually constrained, and the complexity of resource allocation with the goal of improving resource utilization is significantly increased. On the other hand, the low-orbit satellite communication system itself has high dynamics, including the frequent switching of wave positions caused by the high-speed movement of users relative to the satellite, the random access and exit of a large number of users, etc., which puts forward higher dynamic response ability and flexible adaptability to the uplink communication resource allocation. Therefore, for mobile users who need to initiate business communication at any time, how the satellite system efficiently and reasonably allocates reasonable uplink channel resources from the three-dimensional resources of beam, frequency and time slot has become a key problem to be solved.

[0004] The existing technical solutions mainly include:

[0005] Based on the pre-planned fixed allocation mode: the ground system of the satellite allocates specified beam, frequency and time slot resources for the user according to the user's activity area and application mode through pre-planned mode, and uploads the resource allocation result to the satellite through the feeder and inter-satellite link. The satellite schedules the uplink channel resources for the user according to the uploaded resource allocation result. This mode is simple to allocate and easy to implement on the satellite device, but since the mobile trajectory and real bandwidth demand of each user cannot be accurately predicted in the planning stage, this mode is mainly used to protect a small number of important fixed users, lacks flexibility and dynamic adaptability, has low resource utilization, and cannot provide matching uplink resources for mobile users with random access.

[0006] Polling allocation mode based on beam partition: the satellite system divides the coverage area under the satellite into multiple sub-areas according to the number of available beams, and each beam is responsible for serving multiple wave positions in a single sub-area. During the process of service communication, the satellite schedules the corresponding beam resources for each sub-area, and polls all wave positions in the sub-area in a specific order. Only the users who are polled can send data on the specified uplink beam resources. This allocation mode is simple to operate and suitable for satellite communication systems with a large number of users and a relatively uniform geographical distribution. This method mainly has the following two disadvantages. First, in most cases, users are not evenly distributed in geographical space, and the communication traffic volume and channel resource demand vary greatly among sub-areas and wave positions. In particular, some wave positions do not have users using resources, and users of other wave positions cannot use the resources, which easily causes a large waste of resources and congestion of some wave positions. Second, this mode can cause large uplink service delay when the number of wave positions is large, and cannot guarantee that users with random access can quickly enjoy satellite resources.

[0007] The existing technical solutions have their own limitations. The fixed allocation based on pre-planning has low resource utilization and cannot support user random access. The polling allocation mode based on beam partition has inherent defects such as uneven resource allocation and large delay. Therefore, the existing technical solutions cannot meet the efficient uplink resource allocation needs of multiple mobile users with random access. SUMMARY

[0008] Therefore, the present application provides a resource dynamic allocation method and system for multi-beam low-orbit satellite uplink communication, which has high resource utilization, supports user random access and exit, supports flexible networking of multiple users, and is suitable for resource dynamic allocation of multi-beam low-orbit satellite uplink communication, on the basis of real-time acquisition of user information such as wave position, uplink bandwidth demand and uplink rate limit.

[0009] The present application discloses a resource dynamic allocation method for multi-beam low-orbit satellite uplink communication, which comprises:

[0010] The user management unit senses the user access to the satellite communication network and sends a resource request to the uplink resource allocation unit. The uplink resource allocation unit allocates uplink beam, time slot and channel resources to the user after receiving the resource request, and sends the resource allocation result to the user management unit and the satellite transmission unit respectively. The user management unit sends the received resource allocation result to the user. The satellite transmission unit schedules the specified beam to receive the uplink data of the user in the specified channel and time slot according to the resource allocation result.

[0011] Further, it further comprises:

[0012] The user management unit senses that a user joins the satellite communication network, sends a resource allocation request to the uplink resource allocation unit, carrying the user's level, wave position, uplink bandwidth requirement and uplink rate limit information; the uplink resource allocation unit receives and allocates uplink beams, time slots and channel resources for the user, and sends the resource allocation result to the user management unit, which receives and sends the uplink resource allocation result to the user through the downlink;

[0013] The user management unit senses that the user's wave position is switched during network operation, sends a resource reallocation request to the uplink resource allocation unit, carrying the user's new wave position information, the uplink resource allocation unit receives, clears the user's original uplink resources, and reallocates uplink resources for the user, and sends the resource allocation result to the user management unit, which receives and sends the uplink resource allocation result to the user through the downlink;

[0014] The user management unit senses that the user exits the satellite communication network, sends a resource release request to the uplink resource allocation unit, which receives and clears the user's original uplink resources.

[0015] Further, the uplink resource allocation unit allocates uplink beams for the user, including:

[0016] Step 11: The uplink resource allocation unit extracts the user's user level and the wave position C u information;

[0017] Step 12: The uplink resource allocation unit calculates the available beam set P of the user;

[0018] Step 13: The uplink resource allocation unit determines whether the available beam set P is empty, if not, go to step 14, otherwise terminate the allocation;

[0019] Step 14: The uplink resource allocation unit calculates the value of the available beam set P representing the load state of each beam according to the current number of coverage wave positions and the equivalent number of users of the beam;

[0020] Step 15: The uplink resource allocation unit determines the user's level, if the user is an important user, go to step 16; if the user is a normal user, go to step 17;

[0021] Step 16: The uplink resource allocation unit determines whether there is an idle reserved beam in the available beam set P, if yes, go to step 112, otherwise go to step 17;

[0022] Step 17: The uplink resource allocation unit determines whether one or more beams in the available beam set P cover the same wave position C u , if yes, go to step 18, otherwise go to step 19;

[0023] Step 18: The uplink resource allocation unit selects the beam with the minimum generation value from the one or more beams in the available beam set P that cover the same wave position C and allocates it to the user, and then goes to step 113 to update the beam resource allocation table; u Step 19: The uplink resource allocation unit determines whether there is a free non-reserved beam in the available beam set P, and if so, goes to step 110, otherwise goes to step 111;

[0024] Step 19: The uplink resource allocation unit determines whether there is a free non-reserved beam in the available beam set P, and if so, goes to step 110, otherwise goes to step 111;

[0025] Step 110: The uplink resource allocation unit selects the beam with the minimum beam number from all the free non-reserved beams in the available beam set P and allocates it to the user, and then goes to step 113 to update the beam resource allocation table;

[0026] Step 111: The uplink resource allocation unit selects the beam with the minimum generation value from the available beam set P and allocates it to the user, and then goes to step 113 to update the beam resource allocation table;

[0027] Step 112: The uplink resource allocation unit selects the beam with the minimum beam number from all the free reserved beams in the available beam set P and allocates it to the user, and then goes to step 113 to update the beam resource allocation table;

[0028] Step 113: The uplink resource allocation unit updates the relevant table entry of the allocated beam in the resource allocation table.

[0029] Further, the step 12 comprises:

[0030] The available beam set P is initialized to be empty, and all the uplink beams b1~bn are traversed according to the user level of the user; B , and the beam that meets the condition is added to the set P; if the user is an important user, if a beam meets the conditions of covering less than Nc wave positions and having less than Nu equivalent users at the same time, the beam is added to the set P; if the user is an ordinary user, if a beam meets the conditions of covering less than Nc wave positions, having less than Nu equivalent users, and being a non-reserved beam at the same time, the beam is added to the set P; wherein Nc and Nu are respectively the upper limit of the number of covered wave positions and the upper limit of the number of equivalent users preset by the system.

[0031] Further, the system presets different upper limits for the number of reserved beams and non-reserved beams, the upper limit of the number of covered wave positions of the reserved beam is preset as Nc1, the upper limit of the number of equivalent users of the reserved beam is preset as Nu1, the upper limit of the number of covered wave positions of the non-reserved beam is preset as Nc2, the upper limit of the number of equivalent users of the non-reserved beam is preset as Nu2, the values of Nc and Nu depend on the number of carriers and the number of time slots of the uplink beam resource, and satisfy Nu2>Nc2≥Nu1>Nc1.

[0032] Further, after the uplink resource allocation unit completes the beam allocation for the user, the uplink bandwidth requirement, the uplink rate limit, the wave position, and the beam allocation result information of the user are extracted, and the time-frequency resource allocation process for the user is started.

[0033] Further, the time-frequency resource allocation process for the user includes:

[0034] Step 21: Calculate the time slot requirement number Si, calculate the same wave position available time slot set and count the time slot number Sp contained in the same wave position available time slot set, calculate the available time slot number of the empty wave position and count the time slot number Sw contained in the empty wave position available time slot set;

[0035] Step 22: The uplink resource allocation unit determines whether Si≤Sp is true, if yes, go to step 23, otherwise go to step 24;

[0036] Step 23: The uplink resource allocation unit selects Si time slots for the user from the same wave position available time slot set u according to the uniformity principle, so that the variance of the time slot number difference of all adjacent time slots selected is minimum; and then go to step 33;

[0037] Step 24: The uplink resource allocation unit determines whether 0<Sp<Si is true, if yes, go to step 25, otherwise go to step 29;

[0038] Step 25: The uplink resource allocation unit determines whether Sw>0 is true, if yes, go to step 26 to determine whether Sw≥Si-Sp is true, otherwise go to step 23;

[0039] Step 26: The uplink resource allocation unit determines whether Sw≥Si-Sp is true, if yes, go to step 27, otherwise go to step 28;

[0040] Step 27: The uplink resource allocation unit selects Si time slots for the user in total, in which all Sp time slots are selected from the same wave position available time slot set, and then Si-Sp time slots are selected from the empty wave position available time slot set according to the uniformity principle, so that the variance of the time slot number difference of all adjacent time slots selected is minimum; and then go to step 33;

[0041] Step 28: The uplink resource allocation unit selects Sp+Sw time slots for the user in total, in which all Sp time slots are selected from the same wave position available time slot set, and then all Sw time slots are selected from the empty wave position available time slot set; and then go to step 33;

[0042] Step 29: The uplink resource allocation unit determines whether Sw>0 is true, if yes, go to step 30, otherwise go to step 36 to terminate the allocation;

[0043] Step 30: The uplink resource allocation unit judges whether Sw≥Si is true, if yes, it goes to step 31, otherwise it goes to step 32;

[0044] Step 31: The uplink resource allocation unit selects Si time slots for the user from the set of available time slots of the same beam according to the uniformity principle, so that the variance of the time slot number difference of all adjacent time slots selected is minimum, and then goes to step 33;

[0045] Step 32: The uplink resource allocation unit selects all Sw time slots for the user from the set of available time slots of the same beam, and then goes to step 33;

[0046] Step 33: The uplink resource allocation unit assigns a frequency channel to each time slot selected for the user according to the principle of small frequency channel number, that is, selects the beam b u with the smallest sequence number of the idle frequency channel on the time slot, and then goes to step 34;

[0047] Step 34: The uplink resource allocation unit updates the relevant information under the beam b u in the time-frequency resource allocation table according to the time slot and frequency channel resources selected for the user, and the relevant information includes the beam and the user, and then goes to step 35;

[0048] Step 35: The uplink resource allocation unit outputs the resource allocation result, which contains the beam number, time slot number and frequency channel number information allocated for the user, and sends the resource allocation result to the user management unit and the satellite transmission unit;

[0049] Step 36: The uplink resource allocation unit terminates the resource allocation process for the user, and feeds back to the user management unit that the allocation result is caused by insufficient resources.

[0050] Further, the number of time slots required by the user in the time frame Si is calculated by the following formula:

[0051]

[0052] Wherein, Tf is the time frame length, Ts is the time slot length, Rq is the uplink bandwidth requirement of the user, Rm is the uplink rate limit of the user, and ceil is the upward rounding.

[0053] Further, the set of available time slots of the same beam includes:

[0054] The uplink resource allocation unit calculates the set of available time slots of the same beam b u according to the maintained time-frequency resource allocation table, the beam allocation result of the user and the beam C u of the user:

[0055] Q1 is initialized to be empty, and the beam b uIn each time slot t j , 1≤j≤T, T is a time frame, if the following three conditions are met, time slot t j is added to the same beam available time slot set Q1; the first condition is that beam b u covers beam C j in time slot t u , that is, beam C(b u , t j ) = C u ; the second condition is that there is an idle channel in beam b u in time slot t j , that is, at least one channel U(b u , f k, t j ) is empty, 1≤k≤F; the third condition is that time slot t u in beam b j is not allocated to a user, that is, there is no channel U(b u , f k, t j ) = u, 1≤k≤F; F is the total number of channels corresponding to beam b u .

[0056] Further, the calculation of the available time slots of the empty beam includes:

[0057] The uplink resource allocation unit calculates the empty beam available time slot set of beam b u according to the maintained time-frequency resource allocation table and the beam allocation result of the user:

[0058] The empty beam available time slot set is initialized to be empty, and each time slot t j of beam b j in the allocation period, 1≤j≤T, T is a time frame, if the following two conditions are met, time slot t u is added to the empty beam available time slot set; the first condition is that beam b j does not cover any beam in time slot t u , that is, beam C(b j , t u ) is empty; the second condition is that there is an idle channel in beam b j in time slot t u , that is, at least one channel U(b k, , f j t u ) is empty, 1≤k≤F; F is the total number of channels corresponding to beam b B .

[0059] The application further discloses an uplink resource allocation and scheduling system suitable for a multi-beam low-orbit satellite communication system.

[0060] The user management unit is configured to acquire user information of each user in real time, the user information including a level of the user, a wave position in which each user is located, an uplink bandwidth requirement of each user, and an uplink rate limit of each user, and send a resource allocation request to the uplink resource allocation unit when the user accesses the satellite communication network or re-accesses the satellite communication network after wave position switching, the resource allocation request carrying the level, the wave position, the uplink bandwidth requirement, and the uplink rate limit of the user; the level of the user includes an important user and a common user;

[0061] The uplink resource allocation unit is configured to calculate an available beam set of the user and a generation value representing a load state of each available beam according to the level and the wave position information of the user by using a beam resource allocation table maintained in real time, allocate an uplink beam for the user, update the beam resource allocation table, calculate a time slot requirement number of the user in a time frame according to the uplink bandwidth requirement and the uplink rate limit of the user, and calculate an available time slot set of the user in the same wave position and an available time slot set of the user in an empty wave position according to a maintained time-frequency resource allocation table in sequence, allocate an uplink time slot for the user on the allocated beam, allocate an idle frequency channel for each allocated uplink time slot, and update the time-frequency resource allocation table; after the uplink resource allocation for the user is completed, the resource allocation unit sends a resource allocation result to the user management unit and the satellite transmission unit.

[0062] The user management unit is configured to send the received resource allocation result to the user; and the satellite transmission unit is configured to schedule the designated beam to receive uplink data of the user in a designated time slot and a designated frequency channel according to the resource allocation result.

[0063] Thanks to the above technical solutions, the application has the following advantages:

[0064] 1. The application has higher resource utilization, supports multi-user on-demand dynamic scheduling of satellite uplink beam resources. In the uplink beam resource scheduling, according to the user information such as the number of users accessing the satellite communication network, user wave position, uplink bandwidth demand, uplink rate limit, the uplink beam and time-frequency resources are dynamically allocated. On the one hand, in the beam allocation, for ordinary users, the principle of wave position aggregation is followed, and the newly accessed users are allocated on the same wave position beam as much as possible, which meets the limitation that the beam can only cover one wave position at the same time, better reuses the multi-channel resources in the same beam, avoids the problem of beam resource waste caused by allocating multiple same wave position users in different beams, and at the same time, for the case of multiple same wave position beams, the beam with light load is preferentially selected, which is beneficial to the balanced allocation of beam resources. On the other hand, in the time-frequency resource allocation, the time-frequency resource blocks are strictly allocated according to the user's uplink bandwidth demand and uplink rate limit, which accurately matches the user's demand and ability, and avoids resource waste. In addition, when selecting time-frequency resources for users, the principle of same wave position time slot priority over empty wave position time slot is followed, and multi-user multiplexing of the same time slot resource is realized as much as possible through frequency division, which further improves the resource utilization efficiency. Finally, when allocating frequency channel resources for users, the principle of small serial number is followed, and the allocated frequency is concentrated to the low segment as much as possible, which avoids the fragmentation of frequency resources. Therefore, compared with the prior art, the resource utilization can be greatly improved, and the resource utilization can be improved by at least 1 / 3 under the same network configuration condition.

[0065] 2. The application has good dynamic adaptability. The uplink resource allocation method proposed in the application dynamically allocates resources according to the real-time sensing of user changes by the user management unit. On the one hand, it can immediately respond to the resource allocation demand of the access user, dynamically allocate reasonable beam and time-frequency resources to it according to the current allocation state of the uplink resource, without static planning resources for it. On the other hand, it can immediately respond to the resource reallocation demand caused by the wave position switching of the user due to relative movement, and can reallocate beam resources for it according to the new wave position, effectively adapting to the relative topology changes of the high-dynamic low-orbit satellite network. In addition, it can also recycle resources in time when the user exits the network at any time, which can be used for resource allocation of subsequent other access users, and has good allocation flexibility. Therefore, compared with the prior art, the application has good dynamic resource allocation capability and can adapt to various dynamic changes of low-orbit satellite network users.

[0066] 3. Good user hierarchical resource guarantee capability. The application distinguishes the levels of users when performing beam allocation, reserves part of beam resources for important users, and the ordinary users cannot use the reserved beams. The important users prefer to use the idle reserved beams, and when the reserved beam resources are insufficient, the important users can share the non-reserved beams with the ordinary users. Different coverage wave bit numbers and equivalent user number upper limits are set for the reserved beams and the non-reserved beams, and the upper limit of the reserved beams is smaller than that of the non-reserved beams, thereby guaranteeing the continuous and stable resource demand of the important users to the greatest extent.

[0067] 4. Low uplink service delay and delay jitter. When allocating time slots to users, the application selects the allocated time slots from the available time slot set according to the uniformity principle, so that the variance of the time slot number difference of all adjacent time slots is minimized. Therefore, when the user transmits uplink data using the time slots, the interval of adjacent time slots is as stable as possible, and the uplink service delay and delay jitter are low. BRIEF DESCRIPTION OF DRAWINGS

[0068] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments described in the embodiments of the application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0069] Figure 1 A typical multi-beam low-orbit satellite communication system schematic diagram;

[0070] Figure 2 A satellite uplink communication resource structure schematic diagram based on MF-TDMA;

[0071] Figure 3 A block diagram of a multi-beam low-orbit satellite uplink communication resource dynamic allocation system;

[0072] Figure 4 A multi-beam low-orbit satellite communication system uplink communication resource structure schematic diagram;

[0073] Figure 5 A block diagram of another multi-beam low-orbit satellite uplink communication resource dynamic allocation system;

[0074] Figure 6 An interaction processing schematic diagram of the user management unit and the uplink resource allocation unit;

[0075] Figure 7 A beam allocation processing flowchart of the uplink resource allocation unit;

[0076] Figure 8 A time-frequency resource allocation processing flowchart of the uplink resource allocation unit;

[0077] Figure 9 Structure diagram of beam resource allocation table maintained for uplink resource allocation unit;

[0078] Figure 10 Structure diagram of time-frequency resource allocation table maintained for uplink resource allocation unit. DETAILED DESCRIPTION

[0079] The present application is further illustrated with reference to the accompanying drawings and embodiments, which are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those skilled in the art shall fall within the scope of protection of the embodiments of the present application.

[0080] Referring to Figure 3 , the satellite uplink communication function is mainly composed of a satellite protocol processing unit and a satellite transmission unit, the satellite transmission unit includes multiple beam receiving units such as beam 1, beam 2, …, and beam B, which are respectively used to receive uplink data sent by users in the coverage area of each beam. The satellite protocol processing unit mainly includes a user management unit and an uplink resource allocation unit, wherein the user management unit is responsible for user management such as network access, network exit, and wave position switching using a user management protocol, and obtains user information such as the level, wave position, uplink bandwidth demand, and uplink rate limit of each user in real time. The uplink resource allocation unit dynamically allocates or releases beam, channel, and time slot resources for users in response to resource allocation or release requests input by the user management unit during network operation, and sends resource allocation result information to the satellite transmission unit and the user management unit.

[0081] Referring to Figure 4 , the resource structure of the uplink communication of the multi-beam low-orbit satellite communication system is shown in the figure. The uplink resource allocation unit divides the B uplink beams b1~b B into two groups, one group is a reserved beam, which is specially allocated to important users; the other group is a non-reserved beam, which can be used by important users and ordinary users. The uplink resource allocation unit divides the total bandwidth of each beam b i into F channels f i1 ~f iF which are orthogonal to each other in the frequency domain, and divides the time frame into T time slots t1~t T in the time domain. Each grid on the beam is called a resource block RB, which is the smallest resource unit that can be allocated by the system.

[0082] Referring to Figure 5 , the user management unit uses a general user management protocol to obtain the level (important user or ordinary user) of each user u1, u2, …, and the wave position C u1 , C u2, …, uplink bandwidth requirement Rq of each user u1 , Rq u2 , …, and uplink rate limit Rm of each user u1 , Rm u2 , …, and sends a resource allocation request to the uplink resource allocation unit, carrying the level, beam, uplink bandwidth requirement and uplink rate limit information of the user u, in the user u's random access to the satellite communication network or beam switching management process, etc. The uplink resource allocation unit first calculates the available beam set of the user u and the value of the available beam set according to the level and beam information of the user u, and updates the beam resource allocation table. Then, the uplink resource allocation unit calculates the number of time slots required by the user u in the time frame according to the uplink bandwidth requirement and uplink rate limit information of the user u, and calculates the available time slot set of the same beam and the available time slot set of the empty beam of the user u according to the maintained time-frequency resource allocation table, and allocates the uplink time slots of the user u in the allocated beam as much as possible to match the bandwidth requirement and as evenly as possible according to the order of the same beam time slot being prior to the empty beam time slot, and allocates the idle frequency channel for each allocated time slot according to the serial number from small to large principle, and updates the time-frequency resource allocation table. The uplink resource allocation unit completes the uplink resource allocation of the user u, and sends the resource allocation result to the user management unit and the satellite transmission unit. The satellite transmission unit schedules the designated beam to receive the uplink data of the user u in the designated time slot and the designated frequency channel according to the resource allocation result.

[0083] Referring to Figure 6 The interaction process between the user management unit and the uplink resource allocation unit is shown in the figure. It mainly includes three resource dynamic allocation interaction situations.

[0084] Situation one: the user management unit senses that the user u joins the satellite communication network, and sends a resource allocation request to the uplink resource allocation unit, carrying the level, beam, uplink bandwidth requirement and uplink rate limit information of the user u. The uplink resource allocation unit receives it and allocates the uplink beam, time slot and frequency channel resources for the user u, and sends the resource allocation result to the user management unit, which receives it and sends the uplink resource allocation result to the user u through the downlink.

[0085] Case 2: The user management unit senses that the user u has switched wave position during network operation, sends a resource reallocation request to the uplink resource allocation unit, carrying the new wave position information of the user, the uplink resource allocation unit receives it, clears the original uplink resource of the user u, and reallocates the uplink resource for the user u, and sends the resource allocation result to the user management unit, which receives it and sends the uplink resource allocation result to the user u through the downlink.

[0086] Case 3: The user management unit senses that the user u exits the satellite communication network, sends a resource release request to the uplink resource allocation unit, which receives it and clears the original uplink resource of the user u.

[0087] Referring to Figure 7 , the beam allocation processing flow of the uplink resource allocation unit is shown in the figure.

[0088] Step 100: The uplink resource allocation unit extracts the user level of the user u and the wave position C u information, starts the beam allocation process for the user u, and goes to step 101 to calculate the available beam set;

[0089] Step 101: The uplink resource allocation unit calculates the available beam set P of the user u, and then goes to step 102 to judge whether P is empty or not;

[0090] The method for calculating the available beam set P of the user u is: first, initialize the available beam set P to be empty, then traverse all the uplink beams b1~b B , and add the qualified beams to the set P. If u is an important user, if a beam satisfies both the conditions of covering wave position number <Nc and equivalent user number <Nu, then add the beam to the set P; if u is an ordinary user, if a beam satisfies all the three conditions of covering wave position number <Nc, equivalent user number <Nu, and the beam being a non-reserved beam, then add the beam to the set P. Wherein, Nc and Nu are respectively the system preset upper limit of the covering wave position number and the upper limit of the equivalent user number. The system presets different upper limits for the reserved beams and the non-reserved beams, the upper limit of the covering wave position number of the reserved beam is preset as Nc1, the upper limit of the equivalent user number of the reserved beam is preset as Nu1, the upper limit of the covering wave position number of the non-reserved beam is preset as Nc2, and the upper limit of the equivalent user number of the non-reserved beam is preset as Nu2. The specific values of Nc and Nu depend on the carrier number and the time slot number of the uplink beam resource, and satisfy Nu2>Nc2≥Nu1>Nc1.

[0091] Step 102: The uplink resource allocation unit judges whether the available beam set P is empty or not, if not, goes to step 103 to calculate the generation value of each beam, otherwise goes to step 113 to terminate the allocation;

[0092] Step 103, the uplink resource allocation unit calculates the value of each beam in the available beam set P according to the current number of coverage wavelets and the number of equivalent users of the beam The smaller the value, the lighter the load of the beam. Wherein, nc is the current number of coverage wavelets of the beam, nu is the current number of equivalent users of the beam, Nc is the upper limit of the number of coverage wavelets of the beam, Nu is the upper limit of the number of equivalent users of the beam, F is the number of frequency channels of the beam, and a is a preset proportion factor of the system, 0 < a < 1. Then go to step 104 to judge the user level;

[0093] Step 104, the uplink resource allocation unit judges the level of user u, if u is an important user, then go to step 105 to judge whether there is an idle reserved beam in P; if u is a common user, then go to step 106 to judge whether there is an existing beam covering the same wavelet C u in P;

[0094] Step 105, the uplink resource allocation unit judges whether there is an idle reserved beam in the available beam set P, if yes, then go to step 111 to select an idle reserved beam to allocate to user u, otherwise go to step 106 to judge whether there is an existing beam covering the same wavelet C u in P;

[0095] Step 106, the uplink resource allocation unit judges whether there is one or more beams covering the same wavelet C u in the available beam set P, if yes, then go to step 107 to select the beam with the smallest value to allocate to user u, otherwise go to step 108 to judge whether there is an idle non-reserved beam in P;

[0096] Step 107, the uplink resource allocation unit selects the beam with the smallest value from one or more beams covering the same wavelet C u in the available beam set P to allocate to user u, and then goes to step 112 to update the beam resource allocation table;

[0097] Step 108, the uplink resource allocation unit judges whether there is an idle non-reserved beam in the available beam set P, if yes, then go to step 109 to select an idle non-reserved beam to allocate to user u, otherwise go to step 110 to select the beam with the smallest value from P to allocate to user u;

[0098] Step 109, the uplink resource allocation unit selects the beam with the smallest beam number from all idle non-reserved beams in the available beam set P to allocate to user u, and then goes to step 112 to update the beam resource allocation table;

[0099] Step 110, the uplink resource allocation unit selects the beam with the minimum value from the available beam set P to allocate to the user u, and then goes to step 112 to update the beam resource allocation table;

[0100] Step 111, the uplink resource allocation unit selects the beam with the minimum beam number from all the idle reserved beams in the available beam set P to allocate to the user u, and then goes to step 112 to update the beam resource allocation table;

[0101] Step 112, the uplink resource allocation unit updates the relevant table entry of the allocated beam in the resource allocation table: U = U ∪ {u}, C = C ∪ {C u}, Z is a system preset parameter, and is an integer greater than 1.

[0102] Step 113, the uplink resource allocation unit terminates the resource allocation process for the user u, and feeds back the allocation result to the user management unit as resource shortage causing the failure of allocation.

[0103] Referring to Figure 8 , the time-frequency resource allocation process of the uplink resource allocation unit is shown in the figure.

[0104] Step 200, after the uplink resource allocation unit completes the beam allocation for the user u, the uplink bandwidth demand, the uplink rate limit, the wave position, and the beam allocation result information of the user u are extracted, and the time-frequency resource allocation process for the user u is started, and step 201 is entered to calculate the time slot demand;

[0105] Step 201, the uplink resource allocation unit calculates the number of time slots required by the user u in the time frame according to the uplink bandwidth demand and the uplink rate limit of the user u Tf is the time frame length (s), Ts is the time slot length (s), Rq is the uplink bandwidth demand (bps), Rm is the uplink rate limit (bps), and ceil is the upward rounding. Then step 202 is entered to calculate the available time slot set of the same wave position;

[0106] Step 202, the uplink resource allocation unit calculates the available time slot set Q1 of the same wave position of the beam b u according to the maintained time-frequency resource allocation table, the beam allocation result b u of the user u, and the wave position C u of the user u, and counts the number of time slots Sp contained in Q1. Then step 203 is entered to calculate the available time slot number of the empty wave position;

[0107] Q1 is initialized to be empty, and each time slot t u of the beam b j in the allocation period is traversed, 1≤j≤T, if the following three conditions are met simultaneously, the time slot t jJoin the same-wavelength available time slot set Q1. Condition 1 is beam b u In time slot t j Covering wave position C u , that is, C(b u ,t j )=C u ; Condition 2 is beam b u Time slot t j There is an idle channel on the U(b u ,f k ,t j ) is empty, 1≤k≤F; Condition three is beam b u Time slot t j Not assigned to user u, that is, there is no U(b u ,f k ,t j )=u,1≤k≤F;

[0108] Step 203: The uplink resource allocation unit allocates resources based on the time-frequency resource allocation table maintained and the beam allocation result b of user u. u , calculate beam b u The method is as follows: the set of available time slots Q2 with empty wavelengths is obtained, and the number of time slots Sw contained in Q2 is counted. Then, the process goes to step 204 to determine whether Si≤Sp is established;

[0109] Q2 is initialized to empty and traverses beam b u Each time slot t in the allocation period j , 1≤j≤T, if the following two conditions are met at the same time, then the time slot t j Add the empty beam position available time slot set Q2. Condition 1 is beam b u In time slot t j No wave position is covered, that is, C(b u ,t j ) = empty; condition 2 is beam b u Time slot t j There is an idle channel on the U(b u ,f k ,t j ) is empty, 1≤k≤F;

[0110] In step 204, the uplink resource allocation unit determines whether Si≤Sp is established. If so, it proceeds to step 205 to uniformly select Si time slots from Q1. Otherwise, it proceeds to step 206 to determine whether 0 <Sp<Si是否成立;

[0111] Step 205, the uplink resource allocation unit selects Si time slots for user u from Q1 according to the uniformity principle, so that the variance of the time slot number difference of all adjacent time slots selected is minimum. Then go to step 215 to allocate frequency channel number;

[0112] Step 206, the uplink resource allocation unit judges whether 0 < Sp < Si is true, if yes, go to step 207 to judge whether Sw > 0 is true, otherwise go to step 211 to judge whether Sw > 0 is true;

[0113] Step 207, the uplink resource allocation unit judges whether Sw > 0 is true, if yes, go to step 208 to judge whether Sw ≥ Si - Sp is true, otherwise go to step 205 to select Si time slots from Q1 uniformly;

[0114] Step 208, the uplink resource allocation unit judges whether Sw ≥ Si - Sp is true, if yes, go to step 209 to select all Sp time slots from Q1, and then select Si - Sp time slots from Q2 uniformly, otherwise go to step 210 to select all Sp time slots from Q1, and then select all Sw time slots from Q2;

[0115] Step 209, the uplink resource allocation unit selects Si time slots for user u in total, in which all Sp time slots are selected from Q1, and then Si - Sp time slots are selected from Q2 according to the uniformity principle, so that the variance of the time slot number difference of all adjacent time slots selected is minimum. Then go to step 215 to allocate frequency channel number;

[0116] Step 210, the uplink resource allocation unit selects Sp + Sw time slots for user u in total, in which all Sp time slots are selected from Q1, and then all Sw time slots are selected from Q2. Then go to step 215 to allocate frequency channel number;

[0117] Step 211, the uplink resource allocation unit judges whether Sw > 0 is true, if yes, go to step 212 to judge whether Sw ≥ Si is true, otherwise go to step 218 to terminate the allocation;

[0118] Step 212, the uplink resource allocation unit judges whether Sw ≥ Si is true, if yes, go to step 213 to select Si time slots from Q2 uniformly, otherwise go to step 214 to select all Sw time slots from Q2;

[0119] Step 213, the uplink resource allocation unit selects Si time slots for user u from Q2 according to the uniformity principle, so that the variance of the time slot number difference of all adjacent time slots selected is minimum. Then go to step 215 to allocate frequency channel number;

[0120] Step 214, the uplink resource allocation unit selects all Sw time slots for user u from Q2. Then go to step 215 to allocate channel number;

[0121] Step 215, the uplink resource allocation unit allocates channel number for each time slot selected for user u according to the principle of channel number from small to big, i.e. select beam b u The time slot with the smallest sequence number is allocated to user u. Then go to step 216 to update the time-frequency resource allocation table;

[0122] Step 216, the uplink resource allocation unit updates the beam position and user information in the time-frequency resource allocation table under beam b u according to the selected time slot and channel resource for user u. Then go to step 217 to output the resource allocation result;

[0123] Step 217, the uplink resource allocation unit outputs the resource allocation result, which contains the beam number, time slot number and channel number information allocated for user u, and sends the resource allocation result to the user management unit and the satellite transmission unit.

[0124] Step 218, the uplink resource allocation unit terminates the resource allocation process for user u and feeds back to the user management unit that the allocation result is caused by insufficient resources.

[0125] Referring to Figure 9 , the beam resource allocation table is shown in the figure. The uplink resource allocation unit maintains this beam resource allocation table in real time, which records the allocation identifier, covering beam position and allocation user state information of each beam, for beam allocation process. Among them, the beam allocation identifier indicates whether the current beam is idle, which is initially idle, and will be set to occupied once the allocation user set is non-empty. The beam reservation identifier indicates whether the current beam is a reserved beam or a non-reserved beam, which is pre-set by the system and remains unchanged during the resource allocation process. The allocation user set U indicates which users the current beam is allocated to, which is initially an empty set, and user u will be added to the allocation user set once the beam is allocated to user u. If user u exits the network to release resources or the beam is reallocated due to beam position switching, user u needs to be removed from the allocation user set of the current beam. The covering beam position set C indicates which beam positions the current beam covers, which is equal to the union set of all beam positions of the users in the allocation user set. The equivalent user number nu indicates the number of equivalent users allocated to the current beam, which is initially 0, and needs to be updated according to the level of user u when the beam is allocated to user u or the original resources of user u are cleared.

[0126] Referring to Figure 10The constitution of the time-frequency resource allocation table is shown in the figure. The uplink channel allocation unit maintains the time-frequency resource allocation table in real time, which records the time-frequency resource allocation of each beam and is used in the time-frequency allocation process. Wherein, C(b i , j ) represents the wave position covered by beam b i at time slot t j . Each beam can only cover one wave position at the same time slot, but can cover the same or different wave positions at different time slots. U(b i ,f ik, t j ) represents the user who obtains resource block RB(b i ,f ik, t j ). Different frequency channels of the same time slot on each beam can be allocated to different users for use, but cannot be allocated to the same user for use. C(b i ,t j ) and U(b i ,f ik, t j ) are initially empty. Once RB(b i ,f ik, t j ) is allocated to a user u, U(b i ,f ik, t j ) = u, C(b i ,t j ) = u, and the wave position C u , 1≤i≤B, 1≤j≤T, 1≤k≤F. If resource release or resource reallocation caused by wave position switching due to user u leaving the network occurs during network operation, the uplink channel allocation unit needs to clear all U(b i ,f ik, t j ) originally allocated to the user. C(b i ,t j ) is cleared only when all frequency channels of beam b i at time slot t j are idle.

[0127] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit it. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the present application. Any modification or equivalent replacement without departing from the spirit and scope of the present application should be covered in the protection scope of the claims of the present application.

Claims

1. A method for dynamic resource allocation for multi-beam low-orbit satellite uplink communication, characterized in that: include: The user management unit senses that a user has accessed the satellite communication network and sends a resource request to the uplink resource allocation unit, which carries the user's level, wavelength, uplink bandwidth requirement, and uplink rate limit information. After receiving the resource request, the uplink resource allocation unit allocates uplink beam, time slot, and channel resources to the user and sends the resource allocation results to the user management unit and the onboard transmission unit respectively. The user management unit sends the received resource allocation results to the user via a downlink. The onboard transmission unit schedules the specified beam to receive the user's uplink data on the specified channel and time slot according to the resource allocation results. The uplink resource allocation unit allocates uplink beams to users, including: Step 11: The uplink resource allocation unit extracts the user level and the wave position C of the user u information; Step 12: The uplink resource allocation unit calculates the user's available beam set P; Step 13: The uplink resource allocation unit determines whether the available beam set P is not empty. If it is, it proceeds to step 14; otherwise, the allocation is terminated. Step 14: The uplink resource allocation unit calculates a cost value representing the load status of each beam in the available beam set P based on the number of currently covered beam positions and the number of equivalent users. Step 15: The uplink resource allocation unit determines the level of the user. If the user is an important user, the process proceeds to step 16; if the user is an ordinary user, the process proceeds to step 17. Step 16: The uplink resource allocation unit determines whether there is an idle reserved beam in the available beam set P. If so, the process proceeds to step 112; otherwise, the process proceeds to step 17. Step 17: The uplink resource allocation unit determines whether there are one or more beams in the available beam set P that cover the same beam position C. u If yes, go to step 18, otherwise go to step 19; Step 18: The uplink resource allocation unit covers the same beam position C from the available beam set P u Select the beam with the smallest cost value from one or more beams and assign it to the user, then go to step 113 to update the beam resource allocation table; Step 19: The uplink resource allocation unit determines whether there is an idle non-reserved beam in the available beam set P. If yes, the process proceeds to step 110; otherwise, the process proceeds to step 111. Step 110: The uplink resource allocation unit selects the beam with the smallest beam number from all idle non-reserved beams in the available beam set P and allocates it to the user, then proceeds to step 113 to update the beam resource allocation table; Step 111: The uplink resource allocation unit selects the beam with the smallest cost from the available beam set P and allocates it to the user, then proceeds to step 113 to update the beam resource allocation table; Step 112: The uplink resource allocation unit selects the beam with the smallest beam number from all idle reserved beams in the available beam set P and allocates it to the user, then proceeds to step 113 to update the beam resource allocation table; Step 113: The uplink resource allocation unit updates the relevant entries of the allocated beam in the resource allocation table.

2. The method according to claim 1, characterized in that Also includes: When the user management unit detects that a user has switched wavelengths during network operation, it sends a resource reallocation request to the uplink resource allocation unit, carrying the user's new wavelength information. After receiving the request, the uplink resource allocation unit clears the user's original uplink resources, reallocates uplink resources to the user, and sends the resource allocation result to the user management unit. After receiving the request, the user management unit sends the uplink resource allocation result to the user via the downlink. The user management unit senses that the user has exited the satellite communication network and sends a resource release request to the uplink resource allocation unit. After receiving the request, the uplink resource allocation unit clears the user's original uplink resources.

3. The method according to claim 1, characterized in that The step 12 comprises: Initialize the available beam set P to be empty, and traverse all uplink beams b1~b according to the user level. B , add the beams that meet the conditions to the set P; if the user is an important user, if a beam satisfies both the number of covered wavelets less than Nc and the number of equivalent users less than Nu, then the beam is added to the set P; if the user is an ordinary user, if a beam satisfies both the number of covered wavelets less than Nc, the number of equivalent users less than Nu and the beam is a non-reserved beam, then the beam is added to the set P; where Nc and Nu are the upper limits of the number of covered wavelets and the number of equivalent users preset by the system, respectively.

4. The method according to claim 3, characterized in that The system pre-sets different upper limits for the reserved beams and non-reserved beams respectively. The upper limit of the covered wave positions of the reserved beams is pre-set to Nc1, the upper limit of the equivalent number of users of the reserved beams is pre-set to Nu1, the upper limit of the covered wave positions of the non-reserved beams is pre-set to Nc2, and the upper limit of the equivalent number of users of the non-reserved beams is pre-set to Nu2. The values of Nc and Nu depend on the number of carriers and the number of time slots of the uplink beam resources, satisfying Nu2 > Nc2 ≥ Nu1 > Nc1.

5. The method according to claim 1, wherein After the uplink resource allocation unit completes the beam allocation for the user, it extracts the uplink bandwidth requirement, uplink rate limit, wave position, and beam allocation result information of the user, and starts the time-frequency resource allocation process for the user.

6. The method according to claim 5, characterized in that The time-frequency resource allocation process for the user includes: Step 21: Calculate the number of required time slots Si, calculate the available time slot set of the same wave position and count the number of time slots Sp included in the available time slot set of the same wave position, calculate the available time slots of the empty wave position and count the number of time slots Sw included in the available time slot set of the empty wave position; Step 22: The uplink resource allocation unit determines whether Si ≤ Sp holds. If so, it proceeds to Step 23; otherwise, it proceeds to Step 24; Step 23: The uplink resource allocation unit selects Si time slots for the user from the available time slot set of the same wave position according to the uniformity principle, such that the variance of the differences in the time slot numbers of all selected adjacent time slots is minimized; then it proceeds to Step 33; Step 24: The uplink resource allocation unit determines whether 0 < Sp < Si holds. If so, it proceeds to Step 25; otherwise, it proceeds to Step 29; Step 25: The uplink resource allocation unit determines whether Sw > 0 holds. If so, it proceeds to Step 26 to determine whether Sw ≥ Si - Sp holds; otherwise, it proceeds to Step 23; Step 26: The uplink resource allocation unit determines whether Sw ≥ Si - Sp holds. If so, it proceeds to Step 27; otherwise, it proceeds to Step 28; Step 27: The uplink resource allocation unit selects a total of Si time slots for the user, where all Sp time slots are selected from the available time slot set of the same wave position, and then Si - Sp time slots are selected from the available time slot set of the empty wave position according to the uniformity principle, such that the variance of the differences in the time slot numbers of all selected adjacent time slots is minimized; then it proceeds to Step 33; Step 28: The uplink resource allocation unit selects a total of Sp + Sw time slots for the user, where all Sp time slots are first selected from the available time slot set of the same wave position, and then all Sw time slots are selected from the available time slot set of the empty wave position; then it proceeds to Step 33; Step 29: The uplink resource allocation unit determines whether Sw > 0 holds. If so, it proceeds to Step 30; otherwise, it proceeds to Step 36 to terminate the allocation; Step 30: The uplink resource allocation unit determines whether Sw ≥ Si holds. If so, it proceeds to Step 31; otherwise, it proceeds to Step 32; Step 31: The uplink resource allocation unit selects Si time slots for the user from the available time slot set of the empty wave position according to the uniformity principle, such that the variance of the differences in the time slot numbers of all selected adjacent time slots is minimized, and then it proceeds to Step 33; Step 32: The uplink resource allocation unit selects all Sw time slots for the user from the available time slot set of the empty wave position, and then it proceeds to Step 33; Step 33: The uplink resource allocation unit allocates channels for each time slot selected for the user according to the principle of channel number from small to large, that is, selects beam b u The idle channel with the smallest sequence number in the time slot is allocated to the user, and then the process goes to step 34; Step 34: The uplink resource allocation unit updates the time-frequency resource allocation table for beam b according to the time slot and channel resources selected for the user. u The relevant information includes the wave position and the user, and then proceeds to step 35; Step 35: The uplink resource allocation unit outputs the resource allocation result, which includes the beam number, time slot number, and channel number information allocated to the user, and sends the resource allocation result to the user management unit and the onboard transmission unit; Step 36: The uplink resource allocation unit terminates the resource allocation process for the user and feeds back to the user management unit the allocation result indicating that insufficient resources make allocation impossible.

7. The method according to claim 6, characterized in that The number of time slots Si required by the user in the time frame is calculated using the following formula: Where Tf is the time frame length, Ts is the time slot length, Rq is the user's uplink bandwidth requirement, Rm is the user's uplink rate limit, and ceil is rounded up.

8. The method according to claim 6, characterized in that The calculating of the available time slot set of the same wavelength position includes: The uplink resource allocation unit allocates resources based on the time-frequency resource allocation table, the user's beam allocation result and the user's beam position C. u , calculate beam b u The set of available time slots with the same wavelength: The available time slot set of the same wave position is initialized to empty, and the beam b is traversed u Each time slot t in the allocation period j , 1≤j≤T, T is the time frame, if the following three conditions are met at the same time, then the time slot t j Join the same wavelength available time slot set; condition 1 is beam b u In time slot t j Covering wave position C u , that is, wave position C(b u ,t j )=C u ; Condition 2 is beam b u Time slot t j There is an idle channel on the network, that is, there is at least one channel U(b u ,f k ,t j ) is empty, 1≤k≤F; Condition three is beam b u Time slot t j Not allocated to the user, that is, there is no channel U(b u ,f k ,t j )=u,1≤k≤F;f k is beam b u Corresponding to the kth channel, F is beam b u The total number of corresponding channels.

9. The method according to claim 6, characterized in that The calculating of the number of available time slots of empty wave positions includes: The uplink resource allocation unit calculates beam b according to the maintained time-frequency resource allocation table and the user's beam allocation result. u The set of available time slots with empty wavelengths is: The available time slot set of empty beam positions is initialized to empty, and the beam b is traversed. u Each time slot t in the allocation period j , 1≤j≤T, T is the time frame, if the following two conditions are met at the same time, then the time slot t j Add the empty wave position available time slot set; condition 1 is beam b u In time slot t j No wave position is covered, that is, wave position C(b u ,t j ) is empty; condition 2 is beam b u Time slot t j There is an idle channel on the network, that is, there is at least one channel U(b u ,f k ,t j ) is empty, 1≤k≤F; f k is beam b u Corresponding to the kth channel, F is beam b u The total number of corresponding channels.

10. A dynamic resource allocation system for multi-beam low-orbit satellite uplink communications, characterized in that: include: The user management unit is used to obtain user information of each user in real time, including the user's level, the wave position of each user, the uplink bandwidth requirement of each user, and the uplink rate limit of each user. When the user accesses the satellite communication network randomly or re-accesses the satellite communication network after wave position switching, the user management unit sends a resource allocation request to the uplink resource allocation unit, carrying the user's level, wave position, uplink bandwidth requirement and uplink rate limit information. The user level includes important users and ordinary users. The uplink resource allocation unit is used to calculate the user's available beam set and the cost value representing the load status of each available beam based on the user's level and beam position information using the beam resource allocation table maintained in real time, allocate uplink beams to the user, update the beam resource allocation table, calculate the number of time slots required by the user in the time frame based on the user's uplink bandwidth requirement and uplink rate limit information, and calculate the user's co-wave position available time slot set and empty wave position available time slot set in sequence based on the maintained time-frequency resource allocation table, allocate uplink time slots to the user on the allocated beam in the order of co-wave position time slots taking precedence over empty wave position time slots, allocate idle channels to each allocated uplink time slot, and update the time-frequency resource allocation table; after completing the uplink resource allocation for the user, the resource allocation result is sent to the user management unit and the onboard transmission unit; The user management unit is used to send the received resource allocation result to the user; The onboard transmission unit schedules the designated beam to receive the user's uplink data in the designated channel and time slot according to the resource allocation result.

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