A service flow scheduling method for unmanned aerial vehicle assisted high-speed rail millimeter wave communication scene

Abstract

This invention belongs to the field of mobile communication technology and discloses a service flow scheduling method for high-speed rail millimeter-wave communication scenarios assisted by unmanned aerial vehicles (UAVs). By configuring system parameters such as node location and link parameters, it acquires information such as mobile relay location, candidate link status, and service requirements in real time. It calculates the propagation distance based on the node and mobile relay locations, and uses link parameters to obtain the average load per time slot within a frame. Then, it calculates the minimum number of time slots required for each mobile relay to complete the service through candidate links. Links exceeding the remaining budget of the resource pool are then eliminated to form a feasible candidate set. This scheme can accurately select effective links, avoid resource conflicts and underutilization, and ensure reasonable resource allocation. Based on a scoring system, it selects the optimal link and dynamically updates the candidate set, taking into account both service priority and starvation status. This avoids the problem of high-priority services being squeezed out and weak link services being starved. Furthermore, frame-level cyclic scheduling reduces algorithm complexity and meets the real-time scheduling requirements of high-speed rail scenarios.

Description

Technical Field

[0001] This invention belongs to the field of mobile communication technology, specifically a service flow scheduling method for high-speed rail millimeter-wave communication scenarios assisted by unmanned aerial vehicles (UAVs). Background Technology

[0002] High-speed railway communication systems are important infrastructure for services such as train operation control and on-board monitoring. With the increase in train speed and the variety of services, train-to-ground wireless communication needs to meet requirements such as high throughput and low latency. Millimeter wave communication can provide high capacity support due to its rich spectrum and high transmission rate, while UAV-assisted communication can flexibly supplement the coverage of ground infrastructure.

[0003] Millimeter-wave links are sensitive to obstruction, path loss, and high-speed movement, and are prone to coverage discontinuity issues in areas such as the boundary of base station coverage and mountainous areas. In addition, there are challenges in multi-link selection and limited time slot allocation in UAV-assisted communication, and the differences in the priorities of different services also bring challenges to service assurance.

[0004] Currently, there are two main approaches to address this issue. The first is to rely on ground-based base stations to achieve millimeter-wave coverage along high-speed railways, leveraging the high transmission rates of millimeter waves to meet broadband access demands. The second is to employ drone-assisted communication solutions, deploying drones along railway lines or above areas with weak coverage to maintain line-of-sight propagation with mobile relays on train rooftops, thus filling gaps in ground-based base station coverage and improving service continuity. Furthermore, existing resource scheduling methods often rely on maximizing throughput, minimizing resource requirements, or round-robin fairness to attempt to solve link selection and time slot allocation problems.

[0005] Current technical solutions have several shortcomings, which can be summarized as follows: Existing solutions fail to effectively address the issues of multi-link collaborative scheduling and rational resource allocation in UAV-assisted millimeter-wave communication scenarios for high-speed railways, and cannot fully adapt to differences in service priorities and real-time scheduling requirements. Specifically, simple ground base station coverage cannot guarantee continuity, and UAV-assisted solutions lack joint consideration of ground and air links; scheduling methods do not take service priorities into account, easily leading to high-priority services being squeezed out, and ignoring the starvation problem of weak link services; the algorithm complexity is high, making it difficult to meet frame-level real-time scheduling requirements, and the modeling of resource pool differences is unclear, easily causing resource conflicts or underutilization. Summary of the Invention

[0006] This invention provides a service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios, which solves the problems of ineffective multi-link collaborative scheduling and resource allocation, as well as insufficient adaptability and real-time performance.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios includes the following steps: Configure communication system parameters, which include at least: node location, link parameters, frame structure parameters, service priority parameters, starvation threshold, and compensation coefficient; At the beginning of each scheduling frame, obtain the location of each mobile relay, the availability status of each candidate link, the service data volume requirements of each mobile relay, and the corresponding priority weight; The propagation distance is calculated based on the node location and the mobile relay location, and the average intra-frame per-timeslot load of each mobile relay on each candidate link is calculated in combination with the link parameters. Based on the service data volume requirements and the average load per time slot within the frame, calculate the minimum number of time slots required for each mobile relay to complete the service through each candidate link; Link pairs whose minimum number of time slots exceeds the remaining budget of the corresponding resource pool are removed to form a feasible link candidate set; The score of each candidate link in the feasible link candidate set is calculated based on the intra-frame average load per time slot, the minimum number of time slots, and the priority weight. Select the link with the highest score and allocate the minimum number of time slots required, remove the already served mobile trunks and recalculate the candidate set; Update the hunger age of each mobile relay based on the service results, and proceed to the next frame.

[0008] Preferably, the communication system includes a first ground base station, a second ground base station, a drone, and multiple mobile relays installed on the top of the train; wherein, the first link between the first ground base station and the mobile relays and the second link between the drone and the mobile relays share a time slot resource pool, and the third link between the second ground base station and the mobile relays uses another independent time slot resource pool.

[0009] Preferably, the average intra-frame load per time slot is calculated as follows:

[0010] Let M be the number of bits that the i-th mobile relay can carry in the m-th time slot on the k-th link, and M be the number of time slots per frame.

[0011] Preferably, the number of bits that a single time slot can carry is determined by the product of the achievable rate and the time slot length, wherein the achievable rate is calculated as follows:

[0012] in, For bandwidth, For transmission power, For the transmit antenna gain, For receiving antenna gain, For path loss, This represents the small-scale fading coefficient. This represents the noise power spectral density.

[0013] Preferably, the minimum number of time slots is calculated as follows:

[0014] in, To meet business data volume requirements, This represents the average load per time slot within the frame.

[0015] Preferably, the score for each candidate link in the feasible link candidate set is calculated, specifically including: First, the normalized completion efficiency is calculated based on the average load per time slot within the frame and the minimum number of time slots. Then, the priority score is calculated based on the normalized completion efficiency and the priority weight. Finally, when the hunger age of the mobile relay reaches or exceeds the hunger threshold, a compensation coefficient is superimposed on the priority score to obtain the final score.

[0016] Preferably, the normalized completion efficiency is calculated as follows:

[0017] in, The maximum intra-frame average per-slot payload in the feasible candidate set. The minimum number of slots in the feasible candidate set. Let i be the average intra-frame time-slot load of the i-th mobile relay on the k-th link. The minimum number of time slots required for the i-th mobile relay to complete its service on the k$-th link.

[0018] Preferably, the priority score is calculated as follows:

[0019] in, To normalize the completion efficiency, This refers to priority weights.

[0020] Preferably, the final score is calculated as follows:

[0021] in, Rate the priority. For compensation coefficient, For the age of hunger, This is the hunger threshold.

[0022] Preferably, when selecting the link with the highest score to allocate the minimum number of time slots, if multiple candidate links have the same final score, the candidate link with the smaller number of time slots is selected first. If the number of time slots required is still the same, the candidate link with the larger average load per time slot is selected first. The hunger age is updated as follows: after each frame ends, the hunger age of successfully served mobile relays is reset to zero, and the hunger age of unserved mobile relays is incremented by one.

[0023] Compared with existing technologies, this invention has the following advantages: This invention provides a service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios. By configuring system parameters such as node location and link parameters, it obtains information such as mobile relay location, candidate link status, and service requirements in real time. It calculates the propagation distance by combining node and mobile relay locations, and obtains the average load per time slot within a frame by combining link parameters. Then, it calculates the minimum number of time slots required for each mobile relay to complete the service through candidate links. Links exceeding the remaining budget of the resource pool are then eliminated to form a feasible candidate set. This scheme can accurately select effective links, avoid resource conflicts and underutilization, and ensure reasonable resource allocation. Based on scoring, it selects the optimal link and dynamically updates the candidate set, taking into account service priority and starvation status. This avoids the problem of high-priority services being squeezed out and weak link services being starved. At the same time, frame-level cyclic scheduling reduces algorithm complexity and meets the real-time scheduling requirements of high-speed rail scenarios. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a flowchart of a service flow scheduling method for a drone-assisted high-speed rail millimeter-wave communication scenario according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a communication system according to an embodiment of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0028] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0029] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this invention, it should be noted that unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," and "set up" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components.

[0030] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] like Figure 1 As shown, this embodiment of the invention provides a service flow scheduling method for a drone-assisted high-speed rail millimeter-wave communication scenario, including the following steps: S1: Configure communication system parameters, which include at least: node location, link parameters, frame structure parameters, service priority parameters, starvation threshold, and compensation coefficient; S2: At the beginning of each scheduling frame, obtain the location of each mobile relay, the availability status of each candidate link, the service data volume requirements of each mobile relay, and the corresponding priority weight; S3: Calculate the propagation distance based on the node location and the mobile relay location, and combine the link parameters to calculate the average intra-frame per-timeslot load of each mobile relay on each candidate link; S4: Based on the service data volume requirements and the average load per time slot within the frame, calculate the minimum number of time slots required for each mobile relay to complete the service through each candidate link; S5: Remove link pairs whose minimum number of time slots exceeds the remaining budget of the corresponding resource pool to form a feasible link candidate set; S6: Calculate the score for each candidate link in the feasible link candidate set; S7: Select the link with the highest score and allocate the minimum number of time slots required, remove the served mobile trunks and recalculate the candidate set; S8: Update the hunger age of each mobile relay based on the service results, and proceed to the next frame.

[0032] By configuring system parameters such as node location and link parameters, real-time information such as mobile relay location, candidate link status, and service requirements is obtained. Propagation distance is calculated based on node and mobile relay locations, and the average load per time slot within a frame is derived using link parameters. This allows for the calculation of the minimum number of time slots required for each mobile relay to complete its service through candidate links. Links exceeding the remaining budget in the resource pool are then eliminated to form a feasible candidate set. This scheme can accurately select effective links, avoid resource conflicts and underutilization, and ensure reasonable resource allocation. Selecting the optimal link based on a scoring system and dynamically updating the candidate set balances service priority and starvation status, preventing high-priority services from being overwhelmed and weak link services from being starved. Furthermore, frame-level cyclic scheduling reduces algorithm complexity and meets the real-time scheduling requirements of high-speed rail scenarios.

[0033] The detailed steps are as follows: S1: Configure communication system parameters, which include at least: node location, link parameters, frame structure parameters, service priority parameters, starvation threshold, and compensation coefficient; Before configuring the communication system parameters, the frame structure is scheduled first. Each scheduling frame contains a scheduling phase and multiple transmission time slots. Assume the system has a total of There are one train-top mobile relay, with a candidate transmission link number of... . No. The frame includes a length of scheduling phase and There are 1 equal-length transmission time slots, each time slot having a length of 1. Therefore, the frame length is

[0034] For the first The first mobile relay, the first Candidate link, number Frame number Each time slot is defined. Assign variables to time slots.

[0035] like This indicates that the time slot is allocated to the first... The mobile relay and through the first Single link transmission; if , indicating unallocated. Definition This is a frame-level completion variable.

[0036] like , indicating the first The mobile relay in the 1st Frame through the first One link completes the business flow; if , indicating incomplete; The communication system consists of ground base stations, drones, mobile relays on the top of trains, onboard service terminals, and resource scheduling and control modules.

[0037] The ground base stations, including base station 1 and base station 2, are deployed along the high-speed railway line to provide millimeter-wave downlink transmission to mobile relays on the roof of trains.

[0038] Drones are deployed above areas with weak coverage from ground base stations or in transitional areas between adjacent base stations to provide auxiliary downlinks when direct ground links are insufficient. Drones can connect to the ground network via backhaul links and transmit data to trains via drone-mobile relay links.

[0039] Mobile relays are installed on the top of trains to aggregate service flow demands from corresponding carriages or onboard terminals and receive downlink data from ground base stations or drones.

[0040] The resource scheduling and control module can be deployed on the ground base station side, edge computing node, or centralized control unit to obtain train location, link status, service requirements, and historical service status, and to execute the link selection and time slot allocation algorithm of this invention.

[0041] In this invention, the three candidate links are denoted as follows: Link 1 is the base station 1-mobile relay link, Link 2 is the UAV-mobile relay link, and Link 3 is the base station 2-mobile relay link. Link 1 and Link 2 share the same time slot resource pool, while Link 3 uses an independent time slot resource pool. This resource pool allocation reflects the coupling relationship between UAV-assisted transmission and some ground resources, while ensuring the independent scheduling capability of the other ground base station link.

[0042] S2: At the beginning of each scheduling frame, obtain the location of each mobile relay, the availability status of each candidate link, the service data volume requirements of each mobile relay, and the corresponding priority weight; S3: Calculate the propagation distance based on the node location and the mobile relay location, and combine the link parameters to calculate the average intra-frame per-timeslot load of each mobile relay on each candidate link; This invention takes into account both large-scale path loss and small-scale Ricean fading.

[0043] No. The link is in the 1st Frame number The propagation gain of each time slot is expressed as

[0044] in, For transmission distance, For the first The path loss index of the link. For reference propagation gain.

[0045] The small-scale fading coefficient is expressed as = +

[0046] in, Rice factor, For the line-of-sight component phase, This is the scattering component.

[0047] Therefore, the first The achievable rate of this link in this time slot is =

[0048] in, For bandwidth, For transmission power, For the transmit antenna gain, For receiving antenna gain, For path loss, This represents the small-scale fading coefficient. This represents the noise power spectral density.

[0049] The number of bits that a single time slot can carry is

[0050] Since scheduling decisions are executed once per frame, the average load per time slot within a frame is...

[0051] in Let M be the number of bits that the i-th mobile relay can carry in the m-th time slot on the k-th link, and M be the number of time slots per frame.

[0052] S4: Based on the service data volume requirements and the average load per time slot within the frame, calculate the minimum number of time slots required for each mobile relay to complete the service through each candidate link; set up Indicates the first The mobile relay in the 1st The service data volume requirements of the frame. If through the first... The cumulative data transmitted by the link within this frame Not less than If the business flow is completed, then the business flow is considered complete.

[0053]

[0054] Based on the average intra-frame load per time slot, the minimum number of time slots required to complete this service flow is:

[0055] If the link is unavailable, then let

[0056] in, It is a sufficiently large constant used to represent unreachable or infeasible links.

[0057] S5: Remove link pairs whose minimum number of time slots exceeds the remaining budget of the corresponding resource pool to form a feasible link candidate set; The scheduling objective of this invention is to maximize the number of weighted completed service flows in each frame:

[0058] in, For the first The mobile relay in the 1st The service priority weight of a frame. The higher the weight, the higher the service priority.

[0059] Link 1 and Link 2 share the same resource pool and can serve at most one service flow in any time slot; Link 3 uses an independent resource pool and can serve at most one service flow in any time slot. Each mobile relay can complete a service flow through at most one link in the same frame. The corresponding constraints are:

[0060]

[0061]

[0062] Before each round of scheduling, the system constructs a set of feasible candidates based on the current remaining time slot budget. .set up This represents the remaining time slots in the shared resource pool, corresponding to link 1 and link 2. This represents the remaining time slots in the independent resource pool, corresponding to link 3. The remaining budget for each link is denoted as ,Right now

[0063] The feasible candidate set is

[0064] S6: Calculate the score of each candidate link in the feasible link candidate set based on the average intra-frame load per time slot, the minimum number of time slots, and the priority weight; For each mobile relay-link pair in the candidate set, this invention first defines the normalized completion efficiency:

[0065] in,

[0066]

[0067] This metric reflects both the link transmission capacity and the resource cost required to complete the service. The larger the value, the higher the efficiency of the business flow in that link.

[0068] To introduce service priority, this invention further defines a priority scheduling score:

[0069] because Weight The larger the index The smaller the value, the weaker the compression on the original completion efficiency. Therefore, high-priority services can still maintain strong competitiveness even when the link conditions are slightly worse.

[0070] S7: Select the link with the highest score and allocate the minimum number of time slots required, remove the served mobile trunks and recalculate the candidate set; To prevent some mobile relays from being unavailable for extended periods due to poor link conditions or a large number of required time slots, this invention maintains a starvation age for each mobile relay. This indicates that the mobile relay is in the _____. The number of consecutive frames that have not been served before the current frame. Based on the hunger age, the final scheduling score is...

[0071] in, The hunger threshold, To fix the fair compensation coefficient, This is an indicator function.

[0072] In each round of allocation, the system from Select the candidate pair with the highest final score:

[0073] If multiple candidate pairs have the same score, the one with the highest score is selected. Smaller; if still the same, choose the smaller one. Larger one. Select candidate pair. Then, assign it Each time slot, parallel

[0074] like Then update the shared resource pool:

[0075] like Then update the independent resource pool:

[0076] After allocation is complete, served mobile relays are removed from the candidate set, and the set is updated again based on the remaining budget. This process continues until the candidate set is empty or all resource pools have no available budget.

[0077] S8: Update the hunger age of each mobile relay based on the service results, and proceed to the next frame.

[0078] After the current frame ends, update the starvation age based on whether the mobile relay was successfully served:

[0079] The system outputs the link selection result, time slot allocation result, service completion result, and hunger age for the next frame in the current frame. A weighted hunger rate can be further calculated to monitor system fairness.

[0080] in The smaller the value, the lower the proportion of unserved weighted services, and the better the system's service continuity for differentiated services.

[0081] Compared with existing technologies, this patent has the following technical advantages: 1) Improve the continuity of millimeter-wave communication coverage on high-speed railways. This invention utilizes UAV-assisted links to compensate for link gaps in transitional areas or areas with weak coverage of ground base stations, enabling mobile relays to still obtain services through air links when ground links are insufficient.

[0082] 2) Achieve integrated scheduling for multi-link selection and time slot allocation. This invention does not select links or allocate time slots separately, but rather incorporates three types of links—base station 1, UAV, and base station 2—into a unified candidate set and makes joint decisions based on the constraints of shared resource pools and independent resource pools.

[0083] 3) Improve the guarantee capability of high-priority services. This invention constructs a priority scheduling score in the form of a weighted index, so that high-priority services have a higher chance of scheduling under the same or similar completion efficiency, thus making them more suitable for differentiated service scenarios such as train control, status monitoring and emergency services.

[0084] 4) Alleviating the starvation problem of long-term unserved service flows. This invention records the number of consecutive unserved frames through a starvation age and introduces a compensation term after reaching a threshold, so that weak link or high resource demand service flows are not ignored for a long time, taking into account both priority and long-term fairness.

[0085] 5) Reduced online scheduling complexity. This invention transforms complex time-slot-level mixed integer optimization into an iterative scheduling process based on the required number of time slots at the frame level. It eliminates the need to solve a global integer programming problem each time, making it suitable for online implementation in high-speed railway rapid movement scenarios.

[0086] 6) Resource pool constraints are closer to actual systems. This invention explicitly distinguishes the shared time slot resource pools of base station 1—mobile relay link and UAV—mobile relay link, as well as the independent resource pool of base station 2—mobile relay link, which can avoid resource conflicts and improve resource utilization efficiency.

[0087] 7) Simulation results show that the proposed scheme outperforms the representative baseline scheduling method in terms of the number of weighted completed business flows, the ability to complete high-priority business flows, and the weighted hunger rate. Under the default settings, the number of weighted completed business flows is increased by approximately 22% and 83% respectively compared to the maximum flow scheduling and the unmanned drone scheme.

[0088] See Table 1 for an explanation of patent terminology. Table 1 Explanation of Patent Terminology

[0089] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0090] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A service flow scheduling method for a drone-assisted high-speed rail millimeter-wave communication scenario, characterized in that, Includes the following steps: Configure communication system parameters, which include at least: node location, link parameters, frame structure parameters, service priority parameters, starvation threshold, and compensation coefficient; At the beginning of each scheduling frame, obtain the location of each mobile relay, the availability status of each candidate link, the service data volume requirements of each mobile relay, and the corresponding priority weight; The propagation distance is calculated based on the node location and the mobile relay location, and the average intra-frame per-timeslot load of each mobile relay on each candidate link is calculated in combination with the link parameters. Based on the service data volume requirements and the average load per time slot within the frame, calculate the minimum number of time slots required for each mobile relay to complete the service through each candidate link; Link pairs whose minimum number of time slots exceeds the remaining budget of the corresponding resource pool are removed to form a feasible link candidate set; The score of each candidate link in the feasible link candidate set is calculated based on the intra-frame average load per time slot, the minimum number of time slots, and the priority weight. Select the link with the highest score and allocate the minimum number of time slots required, remove the already served mobile trunks and recalculate the candidate set; Update the hunger age of each mobile relay based on the service results, and proceed to the next frame.

2. The service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenario according to claim 1, characterized in that, The communication system includes a first ground base station, a second ground base station, a drone, and multiple mobile relays installed on the top of the train; wherein, the first link between the first ground base station and the mobile relays and the second link between the drone and the mobile relays share a time slot resource pool, and the third link between the second ground base station and the mobile relays uses another independent time slot resource pool.

3. The service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenario according to claim 1, characterized in that, The calculation method for the average intra-frame load per time slot is as follows: Let M be the number of bits that the i-th mobile relay can carry in the m-th time slot on the k-th link, and M be the number of time slots per frame.

4. A service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios according to claim 3, characterized in that, The number of bits that a single time slot can carry is determined by the product of the achievable rate and the time slot length. The achievable rate is calculated as follows: in, For bandwidth, For transmission power, For the transmit antenna gain, For receiving antenna gain, For path loss, This represents the small-scale fading coefficient. This represents the noise power spectral density.

5. A service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios according to claim 1, characterized in that, The minimum number of time slots is calculated as follows: in, To meet business data volume requirements, This represents the average load per time slot within the frame.

6. A service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios according to claim 1, characterized in that, Calculate the score for each candidate link in the feasible link candidate set, specifically including: First, the normalized completion efficiency is calculated based on the average load per time slot within the frame and the minimum number of time slots. Then, the priority score is calculated based on the normalized completion efficiency and the priority weight. Finally, when the hunger age of the mobile relay reaches or exceeds the hunger threshold, a compensation coefficient is superimposed on the priority score to obtain the final score.

7. A service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios according to claim 6, characterized in that, The method for calculating normalized completion efficiency is as follows: in, The maximum intra-frame average per-slot payload in the feasible candidate set. The minimum number of slots in the feasible candidate set. Let i be the average intra-frame time-slot load of the i-th mobile relay on the k-th link. The minimum number of time slots required for the i-th mobile relay to complete its service on the k$-th link.

8. A service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios according to claim 6, characterized in that, The priority score is calculated as follows: in, To normalize the completion efficiency, This refers to priority weights.

9. A service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios according to claim 1, characterized in that, The final score is calculated as follows: in, Rate the priority. For compensation coefficient, For the age of hunger, This is the hunger threshold.

10. A service flow scheduling method for UAV-assisted high-speed rail millimeter-wave communication scenarios according to claim 1, characterized in that, When selecting the link with the highest score to allocate the minimum number of time slots, if multiple candidate links have the same final score, the candidate link with the smaller number of time slots is selected first. If the number of time slots required is still the same, the candidate link with the larger average load per time slot is selected first. The hunger age is updated as follows: after each frame ends, the hunger age of successfully served mobile relays is reset to zero, and the hunger age of unserved mobile relays is incremented by one.

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