Uplink and downlink scheduling method, apparatus, device, medium, and program product

Abstract

Embodiments of the present application provide uplink and downlink scheduling methods, devices, equipment, media and program products, wherein the uplink and downlink scheduling method comprises: calculating the round-trip delay information of the satellite and the user equipment based on the service area information of the satellite; checking whether the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information conflict based on the time allocation information and the round-trip delay information; if not, scheduling the uplink and downlink at the target time, wherein the time allocation information is used to represent the time when the user equipment performs the scheduling task. By obtaining the service area information of the satellite, calculating the round-trip delay information of the satellite and the user equipment, and checking based on the time allocation information, scheduling conflicts between the uplink and downlink of the user equipment are avoided, thereby effectively improving the time-frequency resource utilization. Resource waste is reduced, the coordination of the uplink and downlink is optimized, and the overall network efficiency is improved.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of satellite communication, and in particular to an uplink and downlink scheduling method, device, equipment, medium and program product. BACKGROUND

[0002] Non-Terrestrial Networks (NTN) extend the coverage of traditional terrestrial cellular networks through satellites and other non-ground facilities, enabling remote areas, oceans and airspace to enjoy communication services. NTN has great potential in emergency response, Internet of Things and global connectivity.

[0003] Although NTN provides wide-area coverage, its time-frequency resource utilization is limited, which is a key bottleneck restricting performance improvement. Due to the long signal propagation delay (RTT) between the satellite and the ground terminal, existing scheduling mechanisms are difficult to efficiently coordinate uplink and downlink resources, resulting in resource waste and potential conflicts.

[0004] Therefore, there is an urgent need for an uplink and downlink scheduling method to improve time-frequency resource utilization. SUMMARY

[0005] In view of this, embodiments of the present application provide an uplink and downlink scheduling method. One or more embodiments of the present application also relate to an uplink and downlink scheduling device, a computing device, a computer-readable storage medium and a computer program product to solve the technical defects in the prior art.

[0006] According to a first aspect of the embodiments of the present application, an uplink and downlink scheduling method is provided, applied to a base station, the base station being deployed on a satellite, comprising:

[0007] calculating round-trip delay information of the satellite and a user equipment based on service area information of the satellite;

[0008] checking whether a first link scheduling time of the user equipment conflicts with a second link scheduling time corresponding to the time allocation information based on the time allocation information and the round-trip delay information, wherein the first link scheduling time and the second link scheduling time are determined based on constraints of link scheduling at a target time;

[0009] if not, scheduling the uplink and downlink at the target time, wherein the time allocation information is used to represent the time of the user equipment performing a scheduling task.

[0010] According to a second aspect of the embodiments of the present application, an uplink and downlink device is provided, applied to a base station, the base station being deployed on a satellite, comprising:

[0011] The computing module is configured to calculate the round-trip delay information of the satellite and the user equipment based on the service area information of the satellite.

[0012] The checking module is configured to check whether the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information conflict based on the time allocation information and the round-trip delay information, wherein the first link scheduling time and the second link scheduling time are determined based on the constraint of performing link scheduling at the target time.

[0013] The scheduling module is configured to schedule the uplink and downlink at the target time if the first link scheduling time and the second link scheduling time do not conflict, wherein the time allocation information is used to represent the time at which the user equipment performs the scheduling task.

[0014] According to a third aspect of the embodiments of the present application, a computing device is provided, comprising:

[0015] a memory and a processor;

[0016] The memory is used to store computer programs / instructions, and the processor is used to execute the computer programs / instructions, which realize the steps of the uplink and downlink method described above.

[0017] According to a fourth aspect of the embodiments of the present application, a computer readable storage medium is provided, which stores computer programs / instructions, which realize the steps of the uplink and downlink method described above when executed by a processor.

[0018] According to a fifth aspect of the embodiments of the present application, a computer program product is provided, comprising computer programs / instructions, which realize the steps of the uplink and downlink method described above when executed by a processor.

[0019] One embodiment of the present application realizes the following: the round-trip delay information of the satellite and the user equipment is calculated based on the service area information of the satellite; whether the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information conflict is checked based on the time allocation information and the round-trip delay information, wherein the first link scheduling time and the second link scheduling time are determined based on the constraint of performing link scheduling at the target time; and the uplink and downlink are scheduled at the target time if the first link scheduling time and the second link scheduling time do not conflict, wherein the time allocation information is used to represent the time at which the user equipment performs the scheduling task. By obtaining the service area information of the satellite, the round-trip delay information of the satellite and the user equipment is calculated, and the checking is performed based on the time allocation information, so as to avoid scheduling conflict of the uplink and downlink of the user equipment, to ensure that the uplink and downlink are not scheduled at the target time and conflict with the existing resource allocation of the user equipment, thereby effectively improving the time-frequency resource utilization rate. The resource waste is reduced, the coordination of the uplink and downlink is optimized, and the overall network efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a schematic diagram of a guard interval and uplink / downlink;

[0021] Figure 2 is a schematic diagram of a round-trip delay calculation method provided by an embodiment of the present application;

[0022] Figure 3 is a flow chart of an uplink / downlink scheduling method provided by an embodiment of the present application;

[0023] Figure 4 is a flow chart of a processing procedure of an uplink / downlink scheduling method provided by an embodiment of the present application;

[0024] Figure 5 is a schematic diagram of another round-trip delay calculation method provided by an embodiment of the present application;

[0025] Figure 6 is a structural schematic diagram of an uplink / downlink scheduling apparatus provided by an embodiment of the present application;

[0026] Figure 7 is a structural block diagram of a computing device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0027] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details presented herein. In other instances, well-known methods have not been described in detail in order to avoid obscuring the present application. Unless otherwise specified, any and all

[0028] The terminology used in this disclosure of one or more embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of one or more embodiments. As used in this disclosure and the appended claims, the singular forms "a," "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0029] It will be understood that, although the terms first, second, etc. can be used herein to describe various information, these terms are not intended to denote a temporal sequence, but are used only to distinguish one piece of information from another. For example, a first can be termed a second, and, similarly, a second can be termed a first, without departing from the scope of one or more embodiments. As used herein, the word "if" can be construed to mean "when" or "in response to determining" or "in response to a determination" depending on the context.

[0030] In addition, it should be noted that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in one or more embodiments of the present application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant laws, regulations and standards of relevant countries and regions, and provide corresponding operation portal for user to choose authorization or refusal.

[0031] Firstly, the terms involved in one or more embodiments of the present application are explained.

[0032] Non-Terrestrial Network: Non-Terrestrial Network, NTN. Non-Terrestrial Network refers to a communication network provided by non-ground infrastructure such as satellites, high-altitude platforms (such as drones or balloons), etc., used to supplement or expand the coverage of traditional terrestrial networks, especially in remote areas, oceans or disaster areas, etc. In scenarios where it is difficult to deploy ground base stations.

[0033] Terrestrial Network: Terrestrial Network, TN. Terrestrial Network refers to a traditional communication network based on ground infrastructure (such as base stations, optical fibers and routers, etc.), widely used in cities and densely populated areas, providing stable and high-speed communication services.

[0034] User Equipment: User Equipment, UE. User Equipment refers to the communication equipment used by end users, such as mobile phones, tablets or Internet of Things devices, used to access the network and realize voice, data and video communication functions.

[0035] Next Generation NodeB: Next Generation NodeB, gNB. Next Generation NodeB is a key infrastructure in 5G network, responsible for providing wireless access services for user equipment, supporting higher data rates, lower latency and wider connectivity capabilities.

[0036] Frequency Division Duplexing: Frequency Division Duplexing, FDD. Frequency Division Duplexing is a communication technology that uses different frequencies to transmit uplink and downlink data simultaneously, enabling two-way communication, suitable for symmetric service scenarios.

[0037] Time Division Duplexing: Time Division Duplexing, TDD. Time Division Duplexing is a communication technology that allocates different time slots on the same frequency to transmit uplink and downlink data respectively, suitable for asymmetric service scenarios, with higher flexibility.

[0038] Evolved Universal Terrestrial Radio Access (E-UTRA): E-UTRA is a wireless access technology in 4G LTE networks that provides higher data rates and lower latency, serving as an important foundation for modern mobile communications.

[0039] Guard Period (GP): Guard Period is a time interval set in time division duplex systems to avoid interference between uplink and downlink, ensuring correct transmission and reception of signals.

[0040] Round-Trip Time (RTT): Round-Trip Time is the time required for a signal to travel from the sender to the receiver and return to the sender, commonly used to measure the latency performance of communication links and is an important parameter for optimizing network scheduling.

[0041] Uplink: Uplink is the communication link from UE to base station or satellite, used to transmit user requests, uploaded data, or other information. It is the core channel from terminal to network in wireless communication systems, often requiring consideration of power limitations and interference management.

[0042] Downlink: Downlink is the communication link from base station or satellite to UE, used to transmit network responses, downloaded data, or other service content. It is the main channel from network to terminal in wireless communication systems, often requiring optimization of resource allocation to improve transmission efficiency and user experience.

[0043] In the E-UTRA system, FDD uses a frequency division duplex communication mode, with the same bandwidth used for uplink and downlink transmission, avoiding interference between uplink and downlink.

[0044] In FDD communication networks, UE also needs to use corresponding frequency bands for simultaneous uplink and downlink signal transmission. However, for Ka frequency bands (a specific frequency band in the electromagnetic spectrum), due to the bandwidth of uplink and downlink frequency bands reaching 400MHz, ordinary UE is limited by antenna processing capability and cannot support simultaneous uplink and downlink transmission, so it adopts uplink and downlink time-sharing transmission, i.e., half-duplex scheduling.

[0045] Half-duplex scheduling UE (HD-UE) uses a transmission mode similar to TDD, but unlike TDD, uplink and downlink use different frequency bands, so there is no interference on the channel. The only limitation is that this type of UE cannot schedule uplink and downlink channels simultaneously, while the base station side can schedule uplink and downlink simultaneously.

[0046] 5G ground network follows the design idea of TDD. For HD-UE, the base station needs to reserve GP between sending downlink signals and receiving uplink signals to avoid UE scheduling uplink and downlink channels at the same time. The length of GP is related to the cell radius. The larger the cell radius, the longer the RTT of signal transmission between the base station and the UE, and the longer the time interval that GP needs to reserve. GP needs to cover the RTT and the uplink and downlink switching time of the UE. Referring to Figure 1 illustrated, Figure 1 is a schematic diagram of a guard interval and uplink and downlink, where DL represents downlink scheduling, UL represents uplink scheduling, and GP is a guard interval.

[0047] Compared with TN network, in NTN network, because the UE is far away from the satellite, according to the maximum RTT mode to reserve GP, a longer time needs to be reserved and cannot be scheduled. For example, for a satellite with an orbital height of 600 km, the distance from the UE to the satellite at the edge of the communication range can reach 1200 km. At this time, the maximum RTT time length is (because the round trip is calculated, multiplied by 2 times):

[0048] RTTmax=2*1200*103 / 3*108=8 (ms)

[0049] According to the protocol, the time slot period is configured as an example of 10 ms, and GP reserves 8 ms and cannot do data transmission, which greatly limits the air transmission efficiency of NTN network. However, compared with TN, the minimum distance of UE from gnb cannot be 0, so the actual RTT exists in a range, and GP only needs to cover the RTT in the range, which greatly reduces the length requirement of GP. Still taking the above satellite as an example, the nearest point to the satellite is the near-earth point, and the minimum RTT time length at this time is:

[0050] RTTmin=2*600*103 / 3*108=4 (ms)

[0051] Therefore, GP length needs to cover RTTmax-RTTmin=4 (ms).

[0052] However, for NTN network, the GP length can still be optimized under certain conditions. Generally, the coverage range of a satellite is relatively large, and the coverage range of the satellite needs to be divided into multiple signaling wave positions. In this scenario, only the RTT range under a signaling wave position can be considered. Taking the divided signaling wave position radius of 25 km as an example, referring to Figure 2 illustrated, Figure 2is a schematic diagram of a round trip delay calculation method provided by an embodiment of the present application, S represents a satellite, circle FGH represents a signaling cell on the ground, C is the center of the circle (i.e. the wave position center), F and G are any two points on the circle, the chord length is d, GH is the diameter of the circle passing through G, which is D, s1 is the transmission distance from the satellite to G, and s2 is the transmission distance from the satellite to F.

[0053] The RTT difference between the UE located at G and F is:

[0054]

[0055] Therefore, within the signaling wave position, GP needs to cover 2*25*103 / 3*108=166 (us) of time. It can be seen that the prior art causes waste of uplink and downlink transmission resources.

[0056] In view of the above problems, in the present application, an uplink and downlink scheduling method is provided, and the present application also relates to an uplink and downlink scheduling device, a computing device, a computer readable storage medium, and a computer program product, which are described in detail one by one in the following embodiments.

[0057] Referring to Figure 3 , Figure 3 is a flowchart of an uplink and downlink scheduling method provided by an embodiment of the present application, which specifically includes the following steps.

[0058] Step 302: calculating the round trip delay information between the satellite and the user equipment based on the service area information of the satellite.

[0059] The round trip delay information refers to the total time of signal transmission between the satellite and the user equipment, including the total time of electromagnetic wave transmission from the satellite to the user equipment and then from the user equipment to the satellite. The service area information contains the specific geographic area covered by the satellite and its boundary, which can be used to determine the relative distance of users at different positions in the area.

[0060] In practical applications, the position data of the satellite and the geographic information of the service area are first acquired, which are usually provided by the satellite operator and updated periodically. The system calculates the specific position of the satellite relative to the earth's surface based on the orbital parameters of the satellite. Then, the geographic distribution within the service area is analyzed using geographic information system technology to identify the positions of the near- and far-geodetic point user equipment. For the near-geodetic point user equipment, it is located directly below the satellite and is the closest; while for the edge user equipment, it is located at the boundary of the service area and is the farthest. The system calculates the distance from each user equipment to the satellite based on these position information, and calculates the round-trip delay information based on the propagation speed of the radio signal (the speed of light). Specifically, the system divides the straight-line distance between the satellite and the user equipment by the speed of light to obtain the one-way delay, and then multiplies by 2 to obtain the round-trip delay. For the calculation method in the step, one optional way is to directly use the geometric distance formula for calculation; another optional implementation way is to use a more complex model to consider the influence of atmospheric refraction and other factors on signal propagation, so as to obtain more accurate round-trip delay information.

[0061] In a specific embodiment of the present application, it is assumed that a low-orbit satellite is providing communication services for its covered service area. The service area is a circular area with a radius of 1000 kilometers. The satellite is currently located 350 kilometers above the center of the service area. The system first determines the specific geographic positions of multiple user equipment within the service area, for example, one user equipment is located at the near-geodetic point and another user equipment is located at the far-geodetic point. The system calculates the actual distance from each user equipment to the satellite through spatial geometric calculation based on the three-dimensional coordinates of the satellite and the two-dimensional geographic coordinates of the user equipment. Subsequently, the system uses the speed of light as a reference to calculate the round-trip delay information. For the near-geodetic point user equipment, the round-trip delay is shorter; while for the edge user equipment, due to the longer distance, the round-trip delay is longer. All these calculation results are recorded for subsequent scheduling tasks.

[0062] Further, the round-trip delay information between the satellite and the user equipment is calculated based on the service area information of the satellite, including: acquiring satellite position information, longitude and latitude information of the center of the service area, and size parameters of the service area; determining an angle offset of the user equipment based on the satellite position information, the longitude and latitude information, and the size parameters, wherein the angle offset is an angle between a position offset of the user equipment on the earth's surface projection relative to the center of the service area and the earth's center; calculating a transmission distance based on the angle offset and the satellite position information, and calculating the round-trip delay information between the satellite and the user equipment based on the transmission distance.

[0063] Among them, the satellite position information provides the orbital position of the satellite, and the longitude and latitude information of the center of the service area and the size parameters of the service area describe the specific position and size of the service area.

[0064] In practical applications, the system first acquires the position information of the satellite, the longitude and latitude information of the service area center, and the size parameters of the service area. These information is usually provided by the satellite operator and updated regularly. Based on these data, the system calculates the angular offset of the user equipment relative to the center of the service area, that is, the angle between the position offset of the user equipment on the projection of the earth's surface and the center of the earth. The calculation of the angular offset takes into account the relative position relationship between the actual geographical position of the user equipment and the center point of the service area. Then, the system uses the position information of the satellite and the angular offset to calculate the transmission distance between the user equipment and the satellite. Specifically, the system derives the transmission distance based on the height of the satellite, the relative position of the user equipment, and the radius of the earth, etc. Based on the transmission distance, the system further calculates the round-trip delay information. For the calculation method in step, one optional way is to directly use the geometric distance formula for calculation; another optional implementation way is to use a more complex model to consider the influence of atmospheric refraction on signal propagation, so as to obtain more accurate round-trip delay information.

[0065] In each signaling wave position covered by the satellite, the system calculates the transmission delay range in the wave position. First, the system determines the distance between the satellite and the center point of the service area according to the position information of the satellite and the longitude and latitude information of the center point of the service area. Then, the system calculates the transmission distance of the wave position edge point to determine the minimum and maximum delay. The minimum delay corresponds to the wave position center point, and the maximum delay corresponds to the wave position edge point. By analyzing the geometric relationship between the satellite, the center of the earth and the center point of the service area, the system can derive the transmission distance of the wave position edge point and calculate the round-trip delay (RTT) range accordingly. In order to cope with the RTT change caused by the movement of the satellite, the system converts the RTT range into the time slot value of the scheduling, and respectively expands one time slot in front and behind to ensure the flexibility and reliability of the scheduling.

[0066] In a specific embodiment of the present application, it is assumed that a low-orbit satellite is providing communication services for its covered service area. The service area is a circular area with a radius of 1000 kilometers. The satellite is currently located 350 kilometers above the center of the service area. The system first determines the specific geographic locations of multiple user devices within the service area, for example, one user device is located in the center of the service area and another user device is located at the edge of the service area. According to the three-dimensional coordinates of the satellite and the two-dimensional geographic coordinates of the user devices, the system calculates the actual distance from each user device to the satellite through spatial geometry. Subsequently, the system uses the speed of light as a reference to calculate the round-trip time delay information. For the user device in the center of the service area, the round-trip time delay is short; while for the user device at the edge of the service area, the round-trip time delay is longer due to the longer distance. All these calculation results are recorded for subsequent scheduling tasks. The system also takes into account the influence of satellite movement, converts the RTT range into scheduling time slots, and appropriately expands the time slot range to ensure the accuracy and flexibility of scheduling.

[0067] Based on this, through accurate calculation of satellite and service area information, the system can accurately determine the round-trip time delay between each user device and the satellite. This accurate time delay information provides key data support for subsequent resource allocation, enabling the system to reasonably arrange the scheduling of uplink and downlink while taking into account the significant propagation delay differences between different user devices, thereby ensuring the reliability and efficiency of communication.

[0068] Step 304: Based on the time allocation information and the round-trip time delay information, check whether the first link scheduling time of the user device and the second link scheduling time corresponding to the time allocation information conflict, wherein the first link scheduling time and the second link scheduling time are determined based on the constraints of link scheduling at the target time.

[0069] Wherein, the time allocation information refers to the specific time-frequency resources allocated by the base station to the user device and its scheduling time, and the round-trip time delay information refers to the total time of signal transmission between the satellite and the user device. The first link scheduling time is the time of the scheduling task (uplink or downlink) of the user device corresponding to the base station side at the current time (UE side), and the second link scheduling time is the time of the scheduling task (downlink or uplink) of the user device corresponding to the base station side in the time allocation information (UE side). The purpose of checking whether the two scheduling times conflict is to ensure that there is no interference between uplink and downlink at the user device side.

[0070] In practical application, the system first acquires time allocation information and round-trip delay information on the base station side. The time allocation information includes specific scheduling tasks (such as uplink or downlink) of each user equipment and the corresponding scheduling time. The system calculates the actual scheduling time on the user equipment side according to these information, taking into account the influence of the round-trip delay. For each user equipment, the system determines the first link scheduling time, that is, the scheduling task time of the corresponding user equipment on the base station side (UE side) at the current time, and determines the second link scheduling time, that is, the other link task time allocated to the user equipment on the base station side (UE side), based on the time allocation information. Next, the system compares the two scheduling times to check whether there is an overlap or conflict. Specifically, the system adds the round-trip delay to the first link scheduling time to obtain the actual receiving or transmitting time on the user equipment side, and compares it with the second link scheduling time. If there is an overlap between the two times, it is considered that the scheduling task is in conflict. For the checking method in the step, an optional way is to introduce a guard interval, that is, to insert a period of time without data transmission between the two scheduling times on the UE side, to avoid potential conflicts.

[0071] In a specific embodiment of the present application, it is assumed that the base station allocates a downlink task to a user equipment at time T1, with a scheduling time of T1, and plans to allocate an uplink task at the same time, with a scheduling time of T2. The system first calculates the actual time of the two scheduling times on the user equipment side, taking into account the influence of the round-trip delay. For example, the transmission delay of the downlink is 50 milliseconds, and the transmission delay of the uplink is also 50 milliseconds. The system adds the downlink delay to the scheduling time T1 on the base station side to obtain the actual receiving time T1' on the user equipment side, and subtracts the uplink delay from T2 to obtain the actual transmitting time T2' on the user equipment side. Then, the system compares T1' and T2' to check whether there is an overlap. If it is found that there is an overlap between T1' and T2', it means that they conflict. If T1 plus the round-trip delay is denoted as T1'', and T2 minus the round-trip delay is denoted as T2'', then comparing T1' and T2' is equivalent to comparing T1'' and T2'' whether they conflict, or comparing T1 and T2'' whether they conflict.

[0072] Further, the time allocation information is time allocation information of the uplink, the first link scheduling time is a time at which the user equipment receives the downlink, and the second link scheduling time is a time at which the user equipment initiates the uplink; based on the time allocation information and the round-trip delay information, the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information are checked for conflict, including: obtaining the time allocation information of the uplink; based on the time allocation information of the uplink and the round-trip delay information, it is checked whether the time corresponding to the target time at which the user equipment receives the downlink and the time at which the user equipment initiates the uplink are in conflict; accordingly, if not, the uplink and downlink are scheduled at the target time, including: if not, the downlink is scheduled at the target time.

[0073] In actual application, the system first obtains time allocation information and round-trip delay information on the base station side. Assuming that the current time slot is n and the round-trip delay is K. The time allocation information includes specific scheduling tasks (such as uplink or downlink) of each user equipment and corresponding scheduling times. The system calculates the actual scheduling time on the user equipment side according to these information, taking into account the influence of the round-trip delay. Specifically, the system sets the first link scheduling time (i.e. the time at which the user equipment receives the downlink) as n+K / 2, because it takes a half of the round-trip delay time for the base station to send downlink data to the user equipment to be received. At the same time, the second link scheduling time (i.e. the time at which the user equipment initiates the uplink) is set as the time at which the base station receives the uplink minus a half of the round-trip delay, i.e. the time at which the base station receives the uplink-K / 2. In order to check whether there is a conflict, the system compares the two times to check whether there is an overlap. For example, the system checks whether n+K and the time at which the base station receives the uplink are in conflict. If there is an overlap between the two times, it is considered that the scheduling task on the UE side is in conflict; if there is no conflict, the uplink or downlink can be scheduled at the target time. For the checking method in the step, an optional way is to introduce a guard interval, i.e. inserting a period of time without data transmission between the two scheduling times of the uplink and the two scheduling times of the downlink, so as to avoid potential conflict.

[0074] In a specific embodiment of the present application, it is assumed that the current time is t = 5 seconds and the round-trip delay is K = 100 milliseconds. The base station allocates a downlink task for a certain user equipment with a scheduling time of t, and plans to allocate an uplink task at the same time, which can be an uplink service scheduling or a periodic scheduling of a public channel. The system determines the time when the base station receives the uplink as T_uplink_receive, which is assumed to be 5.1 seconds. In order to check whether there is a conflict, the system adds the round-trip delay to the time when the base station schedules the downlink, i.e. 5 seconds + 100 milliseconds = 5.1 seconds. Then, the system compares t + K = 5 seconds + 100 milliseconds = 5.1 seconds with the time when the base station receives the uplink T_uplink_receive = 5.1 seconds. Since they are equal, the system judges that there is a potential conflict, so it does not schedule the downlink in this time slot. On the contrary, if the check result shows no conflict, the system will schedule the downlink at the target time. For the uplink scheduling task planned by the base station, according to the protocol requirements, the UE must send uplink scheduling after receiving the downlink UCI, so it does not need to judge the conflict with the service scheduling. However, it still needs to judge whether there is an uplink-downlink conflict with the periodic signal of the public channel. For the uplink target time T_uplink_receive, it is assumed that there is a periodic signal of a downlink public channel with a period of T d , t cd , the system needs to judge whether (T_uplink_receive - K) % T d and t cd exist a potential conflict, where % represents the remainder calculation. If the check result shows a conflict, the system does not schedule the uplink at this time, if there is no conflict, the system will schedule the uplink at the target time.

[0075] Based on this, by accurately calculating and checking the first link scheduling time and the second link scheduling time on the user equipment side, the system can effectively avoid the conflict between the uplink and the downlink. This accurate time management mechanism enables the system to ensure that the task scheduling of different user equipments does not interfere with each other in a complex satellite communication environment, further improving the resource utilization and the overall performance of the network. The system can accurately coordinate the time arrangement of the uplink and the downlink, improving the reliability and efficiency of the communication. In addition, through the detailed check of the target time, the system enhances the adaptability and robustness of the scheduling strategy, ensuring that even in a high-dynamic satellite communication environment, the communication quality can remain efficient.

[0076] Further, the time allocation information of the uplink is a scheduling state index table; obtaining the time allocation information of the uplink comprises: initializing the scheduling state index table based on a target time; setting an identification bit in the scheduling state index table based on a predicted uplink arrival time, wherein the scheduling state index table is used to indicate that there is a scheduling task of the uplink at the time corresponding to the identification bit.

[0077] The scheduling state index table is a data structure used to record whether there is a scheduling task of the uplink at a specific time, and is usually implemented in the form of a bitmap. When the identification bit is "1", it indicates that there is a scheduling task of the uplink at the corresponding time, and when the identification bit is "0", it indicates that there is no scheduling task at the corresponding time. The target time refers to a specific time point at which the system plans to perform scheduling, and the predicted uplink arrival time is the time at which the uplink data arrives at the base station, calculated according to the delay information and the task demand of the user equipment.

[0078] In actual application, the system first initializes the scheduling state index table based on the target time. The scheduling state index table is a bitmap array, and its length corresponds to the time unit (such as symbol, time slot or subframe) within the target time range. In the initial state, all bits are set to "0", indicating that no scheduling task has been allocated. Then, for the planned uplink scheduling, the system sets the corresponding identification bit to "1" in the scheduling state index table according to the expected uplink arrival time.

[0079] In a specific embodiment of the present application, it is assumed that the current target time is n, and the system initializes a scheduling state index table with a length of 11, with all initial values being "0". Subsequently, after completing an uplink scheduling with a target receiving time of n+11, the system sets the identification bits one by one according to the RTT of the possible positions of multiple user equipments. For example, the RTT of a certain UE position is 7.5, and since 11-7.5=3.5, the system sets the 3rd and 4th bits in the scheduling state index table to "1". Finally, the scheduling state index table may appear as [0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0], indicating that there may be a conflict between the scheduling task of the uplink and the UE side between n+3 and n+4. This bitmap form of index table not only facilitates quick query, but also efficiently supports subsequent conflict checking and resource allocation operations.

[0080] Based on this, by using the scheduling state index table to record the scheduling task of the uplink, the system can intuitively and efficiently manage time resources. This mechanism not only reduces the computational complexity in the resource allocation process, but also ensures the accuracy and consistency of the scheduling task. The system can quickly identify which time has been occupied, thereby avoiding potential conflicts between uplink and downlink, further improving the flexibility of scheduling and the overall performance of the network.

[0081] Step 306: If no, then schedule the uplink and downlink at the target time, wherein the time allocation information is used to represent the time at which the user equipment performs the scheduling task.

[0082] If the check result shows that the first link scheduling time and the second link scheduling time have no conflict, then the scheduling of the downlink is performed at the target time; if there is a conflict, then no scheduling is performed.

[0083] In actual application, the system first determines whether the scheduling condition is met based on the previous check result, which includes the service scheduling check result and the periodic scheduling check result of the public channel to be executed. If the first link scheduling time and the second link scheduling time have no conflict, the system determines the specific scheduling task at the target time according to the time allocation information. For example, if the task at the target time is downlink scheduling, the system will send downlink data to the user equipment according to the predetermined time allocation information; if the task is uplink scheduling, the system will notify the user equipment to send uplink data at the target time. In this process, the system needs to ensure that all related time-frequency resources have been correctly allocated and the user equipment is ready to receive or send data.

[0084] In a specific embodiment of the present application, it is assumed that the system plans to schedule a downlink task for a user equipment at a certain time, the scheduling DCI is sent at time T0, the target time is T1, and the HARQ (Hybrid Automatic Repeat reQuest) feedback time is T2. After the system confirms through the previous check step that the first link scheduling time and the second link scheduling time of the downlink scheduling corresponding to T0 and T1 have no conflict, and the first link scheduling time and the second link scheduling time of the uplink scheduling corresponding to T2 have no conflict, the system starts to perform the scheduling task. According to the time allocation information, the system sends the downlink DCI through the PDCCH to the UE at time T0, sends the downlink data through the physical downlink shared channel (PDSCH) to the UE at time T1, and prepares the PUCCH (Physical Uplink Control Channel) resource for receiving the uplink HARQ at time T2. At the same time, the system ensures that all necessary resource preparation and mode switching work have been completed within the protection interval before this time. If the check result shows that there is a conflict, the system will not perform the scheduling task at the target time, but will re-plan the scheduling time to ensure that the subsequent task can be successfully performed.

[0085] Further, the round-trip delay information includes a first delay of the near- ground user equipment and a second delay of the far-ground user equipment; based on the uplink time allocation information and the round-trip delay information, the checking whether the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink at the target time are in conflict includes: in the scheduling state index table, determining a first checking interval based on the target time, the first delay and the second delay, wherein the first checking interval represents a potential conflict interval between the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink; checking whether there is an identification bit in the checking interval; accordingly, if not, scheduling the downlink at the target time, including: if there is no identification bit in the first checking interval, scheduling the downlink at the target time.

[0086] The round-trip delay information includes a first delay (minimum delay) of the near-ground user equipment and a second delay (maximum delay) of the far-ground user equipment. The scheduling state index table is a bitmap structure used to record whether there is an uplink scheduling task at a specific time, and the identification bit is "1" indicating that there is an uplink scheduling task at the corresponding time. The first checking interval refers to a time interval determined based on the target time, the first delay and the second delay, which represents a potential conflict interval between the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink.

[0087] In actual application, the system first acquires the time allocation information and the round-trip delay information on the base station side. Assuming that the current target time is n, the round-trip delay information includes a first delay (minimum delay) and a second delay (maximum delay). The system calculates the first checking interval based on these information to check whether the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink at the target time are in conflict. Specifically, the system adds the first delay and the second delay to the target time n to obtain a preliminary time range, and expands this time range to the entire round-trip delay to form the first checking interval. For example, if the first delay is K1 and the second delay is K2, the first checking interval can be represented as [n+K1, n+K2]. Then, the system checks whether there is a position with identification bit "1" in the first checking interval in the scheduling state index table. If there is no position with identification bit "1" in the checking interval, it is considered that there is no conflict; if there is an identification bit "1", there is a potential conflict, and the scheduling strategy needs to be adjusted. For the checking method in the step, one optional way is to check each time slot in the checking interval one by one; another optional implementation way is to check multiple time slots in batches to improve efficiency.

[0088] In a specific embodiment of the present application, it is assumed that the current target time is n=5 seconds, the first time delay K1=40 milliseconds, and the second time delay K2=80 milliseconds. The system initializes a scheduling state index table, and the initial values are all "0". The scheduling state index table is a bitmap structure, and the identification bit "1" indicates that there is an uplink scheduling task at the corresponding time, which is filled by the uplink scheduling. The system first calculates the first check interval, i.e., [5 seconds+40 milliseconds, 5 seconds+80 milliseconds], which is converted into specific time slots. Assuming that each time slot is 1 millisecond, the check interval is [slot40, slot80]. The system checks whether there is an identification bit "1" between slot40 and slot80 in the scheduling state index table. If the identification bits of all these time slots are "0", the system determines that there is no conflict and schedules the downlink at the target time n. Assuming that the scheduling state index table shows that there is an identification bit "1" at slot41, indicating that the time slot has been occupied, the system will further evaluate whether the scheduling strategy needs to be adjusted or a guard interval needs to be inserted to avoid conflict. If the check result shows no conflict, the system will schedule the downlink at the target time.

[0089] Based on this, by accurately calculating the first check interval and checking the identification bits in the scheduling state index table, the system can effectively avoid the conflict between the uplink and downlink. This mechanism not only ensures that the task scheduling of different user equipment does not interfere with each other, but also improves the resource utilization and the overall performance of the network. The system can accurately coordinate the time arrangement of the uplink and downlink, improving the reliability and efficiency of communication.

[0090] Further, after scheduling the downlink, it further includes: obtaining the scheduling information of the uplink corresponding to the downlink; and setting the identification bit in the scheduling state index table.

[0091] The uplink scheduling information refers to the channel resources for control information or data transmission in the uplink that is planned synchronously when the base station allocates resources for the downlink. These channels include PUCCH and PUSCH (Physical Uplink Shared Channel), which are used for HARQ feedback and uplink data transmission, respectively. k1, k2, and koffset are time offset parameters specified according to the 3GPP protocol, which are used to determine the specific scheduling time of the uplink.

[0092] In practical applications, the system first acquires the uplink scheduling information corresponding to the downlink. For example, after scheduling downlink n, the system calculates the time slot (n+k1+koffset) for scheduling PUCCH for HARQ feedback and the time slot (n+k2+koffset) for scheduling PUSCH for uplink data transmission according to the 3GPP protocol. Then, the system checks whether there is a periodic scheduling of downlink common channels at (n+k1+koffset-K) and (n+k2+koffset-K), where K is the round-trip transmission delay, and the checking method is as described above. If the checking result is conflict-free, the system sets the corresponding identification bits in the scheduling state index table. Specifically, the system sets the (k1+koffset)th and (k2+koffset)th positions in the bitmap to "1" as needed to indicate that there is an uplink scheduling task at these times. For the setting method in the step, one optional method is to calculate each time offset one by one and set it separately; another optional implementation method is to process multiple time offsets in batches and update multiple identification bits in the scheduling state index table at one time, thereby improving the efficiency. In addition, after scheduling is completed, the system moves the bitmap forward by one bit and checks whether there is an uplink common channel scheduling task at n+65. If there is, the system sets the identification bits at the corresponding positions according to the requirement.

[0093] In a specific embodiment of the present application, it is assumed that the currently scheduled downlink slot is n=10, k1=4, k2=8, and koffset=2. The system calculates the time slot (n+k1+koffset)=10+4+2=slot16 for scheduling PUCCH for HARQ feedback and the time slot (n+k2+koffset)=10+8+2=slot20 for scheduling PUSCH for uplink data transmission according to the 3GPP protocol. The system initializes a scheduling state index table, and the initial values are all "0". Then, if there is no periodic scheduling conflict of downlink common channels, the system sets the 16th and 20th positions in the bitmap to "1" to indicate that there is an uplink scheduling task at these times. Subsequently, the system moves the bitmap forward by one bit and checks whether there is an uplink common channel scheduling task at n+65=slot75. If the system detects that slot75 needs to schedule PUSCH, the system sets the 75th position in the bitmap to "1". In this way, the system can accurately record all uplink scheduling tasks related to the downlink.

[0094] Therefore, by combining the common channel scheduling information and the scheduling state index table, the system can efficiently manage the resource allocation of uplink and downlink. This mechanism not only ensures the timeliness and accuracy of HARQ feedback and uplink data transmission, but also avoids potential resource conflicts.

[0095] Further, the time allocation information is the downlink common channel scheduling information, the first link scheduling time is the time when the user equipment initiates the uplink, and the second link scheduling time is the time when the user equipment schedules the downlink common channel; based on the time allocation information and the round-trip delay information, the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information are checked for conflict, including: obtaining the downlink common channel scheduling information; based on the downlink common channel scheduling information and the round-trip delay information, the time when the user equipment initiates the uplink corresponding to the target time and the time when the user equipment schedules the downlink common channel are checked for conflict; accordingly, if not, the uplink and downlink are scheduled at the target time, including: if not, the uplink is scheduled at the target time.

[0096] The first link scheduling time is the time when the user equipment initiates the uplink, and the second link scheduling time is the time when the user equipment schedules the downlink common channel. Checking whether the two scheduling times conflict is to ensure that there is no interference between the uplink and downlink at the user equipment side.

[0097] In practical applications, the system first obtains the downlink common channel scheduling information. These information is usually generated by the base station according to the network demand and the task request of the user equipment, and contains specific scheduling time and corresponding channel resources. Assuming that the current target time is slot n, the system calculates the time when the user equipment initiates the uplink and the time when the user equipment schedules the downlink common channel based on this time. Then, the system adjusts these times using the round-trip delay information to consider the influence of signal propagation delay. For example, if the downlink common channel scheduling time is n, considering the round-trip delay K1 (minimum delay) and K2 (maximum delay), the time when the user equipment initiates the uplink can be represented as [n - K2, n - K1]. The system checks each time in this interval to ensure that they do not conflict with the scheduling time of the downlink common channel. Specifically, the system maps the downlink common channel scheduling time to the corresponding position in the scheduling state index table, and checks one by one whether there is a position with an identification bit of "1" in this interval. If there is no conflict, the uplink and downlink can be scheduled at the target time; if there is a conflict, the scheduling strategy needs to be adjusted or a guard interval needs to be inserted to avoid the conflict.

[0098] In one embodiment of the present application, it is assumed that the current target time is n=0 seconds, the uplink scheduling time is n=60 milliseconds, the first delay K1 in the round-trip delay information is 40 milliseconds, and the second delay K2 is 80 milliseconds. The system first calculates the time range in which the user equipment initiates the uplink, i.e., [60-80ms, 60-40ms]. Assuming that each time slot is 1 millisecond, the range is converted to [-20, 20]. Since the time slot number cannot be negative, the system adjusts it to [0, 20]. Then, the system checks whether there is a position with an identification bit of "1" between slot0 and slot20 in the scheduling state index table. If the identification bits of all these time slots are "0", the system determines that there is no conflict and schedules the uplink at the target time n. Assuming that the scheduling state index table shows that there is an identification bit of "1" at position 1, indicating that the time slot has been occupied, the system further evaluates whether the scheduling strategy needs to be adjusted or a guard interval needs to be inserted to avoid the conflict. If the check result shows that there is no conflict, the system schedules the uplink at the target time and notifies the user equipment to initiate the uplink at the appropriate time.

[0099] Based on this, by accurately calculating and checking the time at which the user equipment initiates the uplink and the time at which the user equipment schedules the downlink common channel, the system can effectively avoid the conflict between the uplink and the downlink.

[0100] Further, the round-trip delay information includes a first delay of a near-ascending node user equipment and a second delay of a far-ascending node; based on the common channel scheduling information of the downlink and the round-trip delay information, the system checks whether the time at which the user equipment initiates the uplink and the time at which the user equipment schedules the downlink common channel at the target time conflict, including: obtaining a time slot offset parameter, determining the actual scheduling time of the uplink based on the time sequence offset parameter and the target time; in the scheduling state index table, determining a second check interval based on the actual scheduling time, the first delay and the second delay, wherein the second check interval represents a potential conflict interval between the time at which the user equipment initiates the uplink and the time at which the user equipment schedules the downlink common channel; checking whether there is an identification bit representing an existing downlink common channel scheduling in the check interval; accordingly, if not, scheduling the uplink at the target time, including; if there is no identification bit in the second check interval, scheduling the uplink at the target time.

[0101] The scheduling state index table is a bitmap structure, and the identification bit of "1" indicates that there is a scheduling task of the downlink common channel at the corresponding time. The time slot offset parameter is used to calculate the actual scheduling time of the uplink according to the time offset specified in the 3GPP protocol. The second check interval refers to a time interval determined based on the actual scheduling time, the first delay and the second delay, which represents a potential conflict interval between the time at which the user equipment initiates the uplink and the time at which the user equipment schedules the downlink common channel.

[0102] In practical application, the system first acquires the scheduling information of the downlink common channel and the round-trip delay information. Assuming that the current target time is n, and the first delay K1 and the second delay K2 are known. The system acquires the time slot offset parameter koffset, and determines the actual scheduling time of the uplink based on the parameter and the target time n. Specifically, the system calculates that the actual scheduling time of the uplink is (n+koffset). Then, the system adjusts the actual scheduling time by using the first delay K1 and the second delay K2 to form a potential conflict interval (i.e., the second check interval) to consider the influence of signal propagation delay. For example, the second check interval can be expressed as [(n+koffset-K2), (n+koffset-K1)]. The system checks whether there is a position with an identification bit of "1" in the interval in the scheduling state index table, and these identification bits represent the scheduling tasks of the existing downlink common channel. If there is no conflict, the uplink and downlink can be scheduled at the target time; if there is a conflict, the scheduling strategy needs to be adjusted or a guard interval needs to be inserted to avoid the conflict.

[0103] In a specific embodiment of the present application, it is assumed that the current target time is n=60 ms, the first delay K1=40 ms, the second delay K2=80 ms, and the time slot offset parameter koffset=50. The system initializes a scheduling state index table, and the initial values are all "0". The system first calculates that the actual scheduling time of the uplink is (60+50)=110. Then, the system calculates the second check interval according to the first delay and the second delay, i.e., [110-80 ms, 110-40 ms]. Assuming that each time slot is 1 ms, the range is converted to [30, 70]. The system checks whether there is a position with an identification bit of "1" in the scheduling state index table between 30 and 70. If the identification bits of all these time slots are "0", the system determines that there is no conflict, and schedules the uplink at the target time n. Assuming that the scheduling state index table shows that there is an identification bit of "1" at 45, indicating that the time slot has been occupied, the system will further evaluate whether the scheduling strategy needs to be adjusted or a guard interval needs to be inserted to avoid the conflict. If the check result shows that there is no conflict, the system will schedule the uplink at the target time, and notify the user equipment to initiate the uplink at the appropriate time.

[0104] Based on this, by accurately calculating and checking the time at which the user equipment initiates the uplink and the time at which the user equipment schedules the downlink common channel, the system can effectively avoid the conflict between the uplink and the downlink.

[0105] Further, the uplink and downlink scheduling method further comprises: updating the service area information of the satellite every predetermined period; and updating the round-trip delay information based on the updated service area information of the satellite.

[0106] The preset time period refers to a time interval in which the system updates the service area information and the round-trip time information periodically, and the calculation basis is to ensure that the RTT change value caused by the satellite movement or the service area change within the time period is less than 1 slot, so as to avoid scheduling conflicts.

[0107] In actual application, the system first determines a reasonable preset time period T according to the orbit parameters of the satellite and the dynamic characteristics of the service area. The calculation of this time period T is based on the speed of satellite movement, orbit height, and the rotation of the earth and other factors, to ensure that the change of the satellite position within T time does not cause the RTT change to exceed the time length of 1 slot. For example, if the time length of each slot is 1 millisecond, it is necessary to ensure that the change value of the RTT within T time is less than 1 millisecond. Then, the system reacquires the latest service area information of the satellite every preset time period T, including the current position of the satellite, the longitude and latitude of the center point of the service area, and the size parameters of the service area. Based on these updated information, the system recalculates the round-trip time information between the satellite and the user equipment. Specifically, the system rederives the first time delay (minimum time delay) of the near-ascending-point user equipment and the second time delay (maximum time delay) of the far-ascending-point user equipment according to the updated satellite position and service area information. Then, the system applies the updated round-trip time information to subsequent uplink and downlink scheduling tasks to ensure the accuracy and reliability of the scheduling strategy.

[0108] In a specific embodiment of the present application, it is assumed that the service area currently covered by a low-orbit satellite is a circular area with a radius of 1000 kilometers, and the satellite is located 350 kilometers above the center of the service area. The system sets the preset time period T to 1 second and ensures that the RTT change value caused by the movement of the satellite within 1 second is less than 1 slot (assuming that each slot is 1 millisecond). The system reacquires the latest position information and service area parameters of the satellite every 1 second. For example, at a certain time, the position of the satellite has changed slightly, and the longitude and latitude of the center point of the service area have also shifted. The system recalculates the first time delay of the near-ascending-point user equipment and the second time delay of the far-ascending-point user equipment according to these updated information. It is assumed that the first time delay changes from 40 milliseconds to 42 milliseconds, and the second time delay changes from 80 milliseconds to 83 milliseconds. The system records these updated time delay information and applies it to subsequent scheduling tasks. In this way, the system can timely reflect the changes of the satellite and the service area, and ensure the accuracy of the scheduling strategy.

[0109] Therefore, by periodically updating the service area information and the round-trip time information of the satellite, the system can dynamically adapt to the influence caused by the movement of the satellite and the change of the service area.

[0110] The uplink and downlink scheduling method is applied to the application, the service area information of the satellite is obtained, the round-trip delay information of the satellite and the user equipment is calculated, and the time allocation information is checked, so as to avoid scheduling conflict of the uplink and downlink of the user equipment, ensure that the uplink and downlink scheduling at the target time will not conflict with the existing resource allocation of the user equipment, and effectively improve the utilization rate of time-frequency resources. Reduce resource waste, optimize the coordination of uplink and downlink, and improve the overall network efficiency.

[0111] The following describes the application of the uplink and downlink scheduling method provided by the application to the HD-FDD of the non-terrestrial network (NTN) as an example. Figure 4 The uplink and downlink scheduling method provided by the application is further described in the application of the uplink and downlink scheduling method provided by the application to the HD-FDD of the non-terrestrial network (NTN) as an example. Wherein, Figure 4 is a process flow diagram of an uplink and downlink scheduling method provided by an embodiment of the application, specifically comprising the following steps.

[0112] Step 402: Calculate the transmission delay range in the wave position in each satellite coverage signaling wave position.

[0113] Specifically, referring to Figure 5 , and Figure 5 is a schematic diagram of another round-trip delay calculation method provided by an embodiment of the application. Wherein, O is the earth center, S is the satellite, C is the wave position center point, the great circle in the figure is the cross section of the plane SOC on the earth, D and E are the wave position edge points, A is the intersection of SO on the earth's surface, and ∠SOC is θ, SO length is h, SC distance is s, and the earth radius is r=6371 (km), then in the triangle SOC:

[0114]

[0115] Wherein, s can be calculated according to the satellite position and the wave beam center point latitude and longitude, h is obtained according to the satellite position, and the minimum and maximum delay respectively correspond to the D and E points in Figure 5 , ∠SOD is θ1, and ∠SOE is θ2, then the distance of SD and SE can be expressed as the following formula (1):

[0116] Formula (1)

[0117] θ1 and θ2 can be expressed as the following formula (2):

[0118] Formula (2)

[0119] Or, the range of s i can be calculated by inequality (3) to save the computing resources of the processor:

[0120] Formula (3)

[0121] Both formula (1) and formula (3) are used to calculate the possible distance from the UE to the satellite, and one of them is actually used. Where d is the wave position radius, that is, the length of arc CD or CE, so the RTT range can be calculated by formula (4):

[0122] Formula (4)

[0123] Convert the range of RTT into a scheduled slot value, and extend it by one slot forward and backward respectively to form the interval (K1, K2), which is to deal with the dynamic fluctuations of RTT caused by the high-speed movement of satellites or the change of user equipment position in the satellite communication system. By extending the slot range, it can be ensured that when the RTT changes due to the relative motion between the satellite and the user equipment, the uplink and downlink scheduling conflicts can still be effectively avoided. This design not only improves the robustness of scheduling, but also ensures the stability and reliability of the communication link, while reducing the waste of resources or performance degradation caused by RTT prediction error.

[0124] Step 404: Record the current slot as n, and make a downlink scheduling judgment.

[0125] Specifically, a bitmap is configured for the initial scheduling of half-duplex user equipment (HD-UE), the length of which is determined by the maximum delay within the coverage of the satellite, for example, set to 64. The bitmap takes the current uplink slot as the reference, and is used to identify whether there is uplink scheduling in the future 64 slots. In the initial state, all bit positions are set to 0, indicating that there is no uplink scheduling yet. The purpose of this step is to create an efficient scheduling state index table to dynamically track the future uplink usage and avoid resource conflicts.

[0126] When scheduling the UE downlink, the gNB first checks whether there is uplink scheduling in the future 64 slots based on the current uplink slot. If there is uplink scheduling in a certain slot, the corresponding bit position is set to 1, and the other bit positions remain unchanged. This operation ensures that the bitmap can accurately reflect the resource occupation of the future uplink, providing a reliable basis for subsequent downlink scheduling and avoiding conflicts caused by the time overlap of uplink and downlink.

[0127] Since the signal transmission from the current downlink slot n to the user equipment needs to go through the time delay of RTT, and the RTT is converted into the slot value in the range of (K1, K2), the actual impact is the uplink slot of n+K. In essence, it is to check whether n+K / 2 (the time point when the signal reaches the user equipment) conflicts with the time point -K / 2 (the time point when the user equipment initiates the uplink signal) represented by 1 in the bitmap. In other words, it is to check whether n+K overlaps with the time point represented by 1 in the bitmap, that is, to check whether there is a bit set to 1 in the range of n+K1 to n+K2. If there is a conflict, wait for the next available slot; otherwise, continue the subsequent check. The scheduling slot of the downlink PDSCH is (n+k0), and after the RTT, the impact is the uplink slot of n+k0+K, so it is also necessary to check whether there is a bit set to 1 in the range of n+k0+K1 to n+k0+K2 in the bitmap. If there is a conflict, wait for the next available slot; otherwise, continue the subsequent check. This checking mechanism effectively avoids the uplink and downlink link conflict caused by satellite movement or RTT fluctuation.

[0128] After completing the scheduling check of the downlink slot n, the PUCCH is scheduled at n+k1+koffset for HARQ feedback, and this uplink scheduling affects the downlink slot of n+k1+koffset-K, so it is necessary to check the downlink common channel scheduling state in the range of (n+k1+koffset-K2, n+k1+koffset-K1). In essence, it is to check whether n+k1+koffset-K / 2 (the time when the uplink signal reaches the satellite) conflicts with the downlink common channel scheduling time +K / 2 (the time when the downlink signal reaches the user equipment), that is, to check whether n+k1+koffset-K overlaps with the downlink common channel scheduling time. If there is a conflict, wait for the next available scheduling slot; otherwise, continue the current scheduling. After completing the scheduling, the bit position k1+koffset in the bitmap is set to "1". This step ensures that the bitmap can accurately record the scheduling state of the future possible HARQ feedback, avoiding conflicts between these key operations and other downlink scheduling. k1, k2 and koffsed are all time slot parameters specified by the 3GPP protocol to ensure that the scheduling meets the standard specifications.

[0129] After each scheduling is completed, the bitmap is shifted forward by one bit, and it is checked whether there is an uplink common channel scheduling requirement for the slot of n+65. If there is, the corresponding bit position is set to "1"; otherwise, it is kept as "0". In this way, the bitmap always maintains the scheduling state tracking of the future 64 slots, ensuring the real-time and accuracy of the scheduling decision. This step realizes the dynamic updating of the bitmap, ensuring that it can continuously support subsequent scheduling operations.

[0130] The above steps of downlink check-scheduling are executed in a loop to constantly check the conflict between downlink and uplink, update the bitmap state and complete the scheduling operation. This loop process constitutes the complete scheduling logic, which ensures that the system can efficiently allocate resources in the dynamically changing satellite communication environment, while avoiding the conflict between uplink and downlink, and improving the overall network performance and user experience.

[0131] Step 406: Record the current slot as n, and perform uplink scheduling judgment.

[0132] Specifically, assuming that the uplink service is scheduled at n, the transmission of the UCI signal of the current downlink slot n to the user equipment needs to go through the time delay of RTT, and the conversion of RTT to slot value ranges from K1 to K2, so the actual impact is the uplink slot of n+K. Essentially, it is to check whether n+K / 2 (the time point when the signal reaches the user equipment) conflicts with the time point -K / 2 (the time point when the user equipment initiates the uplink signal) represented by 1 in the bitmap. In other words, it is to check whether n+K overlaps with the time point represented by 1 in the bitmap, i.e. to check whether there is a bit set to 1 within the range of n+K1 to n+K2. The uplink service PUSCH will be actually transmitted at n+k2+koffset. Due to the existence of RTT in satellite communication, the corresponding downlink signal will coincide with the uplink signal at the time point of n+k2+koffset-K. Therefore, it is necessary to check the scheduling state of the downlink common channel within the range of (n+k2+koffset-k2, n+k2+koffset-k1). Essentially, it is to check whether n+k2+koffset-K / 2 (the time when the uplink signal reaches the satellite) conflicts with the scheduling time of the downlink common channel +K / 2+(the time when the downlink signal reaches the user equipment), i.e. to check whether n+k2+koffset-K overlaps with the scheduling time of the downlink common channel. If there is a conflict, wait for the next available scheduling slot; otherwise, continue the current scheduling, and set the k2+koffset position of 1 in the bitmap in step 404. This step ensures that the bitmap can accurately record the scheduling state of the future possible uplink service, and avoid the conflict between these key operations and other downlink scheduling. This checking mechanism ensures that the uplink scheduling does not interfere with the planned downlink common channel resources.

[0133] According to the 3GPP protocol, koffset>K, so n+k2+koffset-K>n. This indicates that the actual transmission time of the uplink service is always later than the current scheduling time n, thereby avoiding direct overlap in time with the scheduled downlink service. Therefore, in this case, the influence of the scheduled downlink service on uplink scheduling does not need to be considered, and only the conflict that may be caused by downlink common channel scheduling needs to be focused on. This design simplifies the scheduling logic while ensuring the coordination of uplink and downlink and the efficiency of resource allocation.

[0134] Step 408: Periodically perform RTT update calculation.

[0135] Specifically, due to the movement of the satellite, the RTT will change over time, so it is necessary to periodically perform RTT calculation to ensure the accuracy of scheduling. The standard for setting the calculation period T is that the change of RTT within this period will not cause the corresponding slot value to change by more than 1 slot, so that the fluctuation of RTT within each period will not affect the accurate scheduling of uplink and downlink, thereby avoiding resource conflict or scheduling failure caused by inaccurate RTT estimation, and ensuring the stability and reliability of the communication system. This periodic update mechanism can dynamically adapt to the influence of satellite movement and maintain the best state of network performance.

[0136] Corresponding to the method embodiments described above, the application also provides uplink and downlink scheduling device embodiments, Figure 6 is a structural schematic diagram of an uplink and downlink scheduling device provided by an embodiment of the application. As shown in the figure, Figure 6 the device comprises:

[0137] The calculation module 602 is configured to calculate the round-trip time information of the satellite and the user equipment based on the service area information of the satellite;

[0138] The verification module 604 is configured to verify whether the first link scheduling time of the user equipment conflicts with the second link scheduling time corresponding to the time allocation information based on the time allocation information and the round-trip time information;

[0139] The scheduling module 606 is configured to schedule the uplink and downlink at the target time if not, wherein the time allocation information is used to represent the time at which the user equipment performs the scheduling task.

[0140] Optionally, the computing module 602 is further configured to acquire satellite position information, longitude and latitude information of a center of a service area, and size parameters of the service area; determine an angle offset of the user equipment based on the satellite position information, the longitude and latitude information, and the size parameters, wherein the angle offset is an angle between a position offset of the user equipment relative to the center of the service area projected on the surface of the earth and a center of the earth; calculate a transmission distance based on the angle offset and the satellite position information, and calculate the round-trip delay information between the satellite and the user equipment based on the transmission distance.

[0141] Optionally, the time allocation information is time allocation information of the uplink, the first link scheduling time is a time at which the user equipment receives the downlink, and the second link scheduling time is a time at which the user equipment initiates the uplink; accordingly, the checking module 604 is further configured to acquire the time allocation information of the uplink; check whether a time at which the user equipment receives the downlink corresponding to the target time and a time at which the user equipment initiates the uplink corresponding to the target time conflict based on the time allocation information of the uplink and the round-trip delay information; accordingly, the scheduling module 606 is further configured to, if not, schedule the downlink at the target time.

[0142] Optionally, the time allocation information of the uplink is a scheduling state index table; accordingly, the checking module 604 is further configured to initialize the scheduling state index table based on the target time; set an identification bit in the scheduling state index table based on the predicted uplink arrival time, wherein the scheduling state index table is used to indicate that there is a scheduling task of the uplink at a time corresponding to the identification bit.

[0143] Optionally, the round-trip delay information includes a first delay of a near-ascending node user equipment and a second delay of a far-ascending node; accordingly, the checking module 604 is further configured to determine a first checking interval in the scheduling state index table based on the target time, the first delay, and the second delay, wherein the first checking interval represents a potential conflict interval of a time at which the user equipment receives the downlink and a time at which the user equipment initiates the uplink; check whether there is an identification bit in the checking interval; accordingly, the scheduling module 606 is further configured to, if there is no identification bit in the first checking interval, schedule the downlink at the target time.

[0144] Optionally, the checking module 604 is further configured to acquire common channel scheduling information of the uplink corresponding to the downlink; set an identification bit in the scheduling state index table based on the common channel scheduling information.

[0145] Optionally, the time allocation information is common channel scheduling information of the downlink, the first link scheduling time is a time at which the user equipment initiates the uplink, and the second link scheduling time is a time at which the user equipment schedules the downlink common channel; accordingly, the checking module 604 is further configured to obtain the common channel scheduling information of the downlink; based on the common channel scheduling information of the downlink and the round-trip delay information, check whether the time at which the user equipment initiates the uplink corresponding to the target time and the time at which the user equipment schedules the downlink common channel conflict; accordingly, the scheduling module 606 is further configured to, if not, schedule the uplink at the target time.

[0146] Optionally, the round-trip delay information includes a first delay of a near-ascending node user equipment and a second delay of a far-ascending node; accordingly, the checking module 604 is further configured to obtain a time slot offset parameter, determine an actual scheduling time of the uplink based on the time sequence offset parameter and the target time; in the scheduling state index table, determine a second checking interval based on the actual scheduling time, the first delay and the second delay, wherein the second checking interval represents a potential conflict interval of the time at which the user equipment initiates the uplink and the time at which the user equipment schedules the downlink common channel; check whether there is an identification bit representing an existing downlink common channel scheduling in the checking interval; accordingly, the scheduling module 606 is further configured to, if there is no identification bit in the second checking interval, schedule the uplink at the target time.

[0147] Optionally, the uplink and downlink scheduling device further includes a delay updating module configured to update the service area information of the satellite every preset period; update the round-trip delay information based on the updated service area information of the satellite.

[0148] Applied to the uplink and downlink scheduling device, first, the calculation module 602 calculates the round-trip delay information of the satellite and the user equipment based on the service area information of the satellite, ensuring accurate understanding of the actual propagation delay of different user equipment. Then, the checking module 604 uses these round-trip delay information and time allocation information to check whether the first link scheduling time of the user equipment and the second link scheduling time conflict, thereby avoiding potential interference between the uplink and downlink. If the checking result shows no conflict, the scheduling module 606 schedules the uplink and downlink at the target time, ensuring that the scheduling at this time does not conflict with the existing resource allocation of the user equipment. Effectively improve the time-frequency resource utilization, reduce resource waste, and optimize the coordination of the uplink and downlink, improve the overall network efficiency.

[0149] The above is a schematic scheme of the uplink and downlink scheduling device of the embodiment. It should be noted that the technical scheme of the uplink and downlink scheduling device and the technical scheme of the uplink and downlink scheduling method described above belong to the same concept, and the technical scheme of the uplink and downlink scheduling device which is not described in detail can be referred to the description of the technical scheme of the uplink and downlink scheduling method.

[0150] Figure 7 A structural block diagram of a computing device 700 according to an embodiment of the present application is shown. The components of the computing device 700 include, but are not limited to, a memory 710 and a processor 720. The processor 720 is connected to the memory 710 through a bus 730, and a database 750 is used to store data.

[0151] The computing device 700 also includes an access device 740, which enables the computing device 700 to communicate via one or more networks 760. Examples of these networks include the Public Switched Telephone Network (PSTN), a Local Area Network (LAN), a Wide Area Network (WAN), a Personal Area Network (PAN), or a combination of communication networks such as the Internet. The access device 740 can include one or more of any type of network interface (e.g., a network interface card (NIC)) such as a IEEE 802.11 Wireless Local Area Network (WLAN) wireless interface, a Worldwide Interoperability for Microwave Access (Wi-MAX) interface, an Ethernet interface, a Universal Serial Bus (USB) interface, a cellular network interface, a Bluetooth interface, a Near Field Communication (NFC).

[0152] In an embodiment of the present application, the above-mentioned components of the computing device 700 and other components not shown in the Figure 7 may be connected to each other, for example, through a bus. It should be understood that Figure 7 The structural block diagram of the computing device shown is only for the purpose of example, and is not a limitation on the scope of the present application. Those skilled in the art can add or replace other components as needed.

[0153] The computing device 700 can be any type of stationary or mobile computing device, including a mobile computer or mobile computing device (e.g., a tablet computer, a personal digital assistant, a laptop computer, a notebook computer, a netbook, etc.), a mobile phone (e.g., a smartphone), a wearable computing device (e.g., a smart watch, smart glasses, etc.), or other type of mobile device, or a stationary computing device such as a desktop computer or a personal computer (PC). The computing device 700 can also be a mobile or stationary server.

[0154] The processor 720 is configured to execute instructions of a computer program to implement the steps of the above-described uplink and downlink scheduling method.

[0155] Each of the embodiments of the present application is described in a progressive manner, and the same or similar parts among the embodiments can be referred to each other. Each of the embodiments mainly describes the difference from other embodiments. In particular, the computing device embodiment is basically similar to the uplink and downlink scheduling method embodiment, and thus the description is relatively simple, and the relevant parts can be referred to the description of the uplink and downlink scheduling method embodiment.

[0156] An embodiment of the present application further provides a computer readable storage medium storing computer programs / instructions, which are executed by a processor to implement the steps of the above-described uplink and downlink scheduling method.

[0157] Each of the embodiments of the present application is described in a progressive manner, and the same or similar parts among the embodiments can be referred to each other. Each of the embodiments mainly describes the difference from other embodiments. In particular, the computer readable storage medium embodiment is basically similar to the uplink and downlink scheduling method embodiment, and thus the description is relatively simple, and the relevant parts can be referred to the description of the uplink and downlink scheduling method embodiment.

[0158] An embodiment of the present application further provides a computer program product including computer programs / instructions, which are executed by a processor to implement the steps of the above-described uplink and downlink scheduling method.

[0159] The above is a schematic scheme of the computer program product of the embodiment. It should be noted that the technical scheme of the computer program product and the technical scheme of the above-described uplink and downlink scheduling method belong to the same concept, and the details of the technical scheme of the computer program product which are not described in detail can be referred to the description of the technical scheme of the above-described uplink and downlink scheduling method.

[0160] The above described particular embodiments of the application. Other embodiments are within the scope of the following claims. In some cases, the actions or steps recited in the claims can be performed in a different order and still accomplish the desired results. Additionally, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve the desired results. In certain implementations, multitasking and parallel processing can be advantageous or necessary.

[0161] The computer readable medium can include any entity or apparatus capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, software distribution medium, etc.

[0162] It should be noted that, for the foregoing method embodiments, the acts described can be performed in a different order and still achieve the desired results. Additionally, some acts can be performed simultaneously or omitted, and still achieve the desired results. Furthermore, some acts can be performed by different entities than those described, and still achieve the desired results.

[0163] In the above embodiments, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0164] The above disclosed preferred embodiments of the present application are only used to help explain the present application. Alternative embodiments do not describe all the details, nor limit the application to the specific embodiments described. Obviously, according to the content of the embodiments of the present application, many modifications and changes can be made. The present application selects and describes these embodiments in order to better explain the principles and practical applications of the embodiments of the present application, so that those skilled in the art can well understand and utilize the present application. The present application is limited by the claims and their full scope and equivalents.

Claims

1. An uplink and downlink scheduling method, characterized by, Applied to a base station, the base station is deployed on a satellite, comprising: Obtaining satellite position information, longitude and latitude information of the center of the service area and size parameters of the service area; Based on the satellite position information, the longitude and latitude information and the size parameters, the angle offset of the user equipment is determined, wherein the angle offset is the angle between the position offset of the user equipment relative to the center of the service area on the earth surface projection and the earth center; Based on the angle offset and the satellite position information, the transmission distance is calculated, and the round trip delay information between the satellite and the user equipment is calculated based on the transmission distance; Based on the time allocation information and the round trip delay information, it is verified whether the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information conflict, wherein the first link scheduling time and the second link scheduling time are determined based on the constraint of link scheduling at the target time, the time allocation information is a scheduling state index table, and the scheduling state index table is a bitmap data structure used to record whether there is a scheduling task at a specific time. The length of the bitmap data corresponds to the time unit within the target time range; If not, schedule uplink and downlink at the target time, wherein the time allocation information is used to represent the time of the user equipment performing scheduling tasks.

2. The method of claim 1, wherein, The time allocation information is the time allocation information of the uplink, the first link scheduling time is the time when the user equipment receives the downlink, and the second link scheduling time is the time when the user equipment initiates the uplink. Based on the time allocation information and the round trip delay information, it is verified whether the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information conflict, comprising: Obtaining the time allocation information of the uplink; Based on the time allocation information of the uplink and the round trip delay information, it is verified whether the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink corresponding to the target time conflict; Correspondingly, if not, schedule downlink at the target time. The time allocation information of the uplink is a scheduling state index table; the time allocation information of the uplink is obtained, comprising:

3. The method of claim 2, wherein, Based on the target time, initialize the scheduling state index table; Based on the predicted uplink arrival time, set the identification bit in the scheduling state index table, wherein the scheduling state index table is used to indicate that there is a scheduling task of the uplink at the time corresponding to the identification bit. The round trip delay information includes the first delay of the near satellite lower point user equipment and the second delay of the far satellite lower point; based on the time allocation information of the uplink and the round trip delay information, it is verified whether the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink corresponding to the target time conflict, comprising:

4. The method of claim 3, wherein, ​ In the scheduling state index table, a first check interval is determined based on the target time, the first time delay and the second time delay, wherein the first check interval represents a potential conflict interval between a time when the user equipment receives the downlink and a time when the user equipment initiates the uplink; It is checked whether there is an identification bit in the check interval; Correspondingly, if not, the downlink is scheduled at the target time, including: If there is no identification bit in the first check interval, the downlink is scheduled at the target time.

5. The method of claim 4, wherein, After the downlink is scheduled, it further includes: Obtaining common channel scheduling information of the uplink corresponding to the downlink; Based on the common channel scheduling information, an identification bit is set in the scheduling state index table.

6. The method of claim 1, wherein, The time allocation information is the common channel scheduling information of the downlink, the first link scheduling time is the time when the user equipment initiates the uplink, and the second link scheduling time is the time when the user equipment schedules the downlink common channel; based on the time allocation information and the round-trip time delay information, it is checked whether the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information conflict, including: Obtaining common channel scheduling information of the downlink; Based on the common channel scheduling information of the downlink and the round-trip time delay information, it is checked whether the time when the user equipment initiates the uplink corresponding to the target time and the time when the user equipment schedules the downlink common channel conflict; Correspondingly, if not, the uplink and downlink are scheduled at the target time, including: If not, the uplink is scheduled at the target time.

7. The method of claim 6, wherein, The round-trip time delay information includes a first time delay of a near-ground user equipment and a second time delay of a far-ground user equipment; based on the common channel scheduling information of the downlink and the round-trip time delay information, it is checked whether the time when the user equipment initiates the uplink corresponding to the target time and the time when the user equipment schedules the downlink common channel conflict, including: Obtaining a time slot offset parameter, determining an actual scheduling time of the uplink based on the time sequence offset parameter and the target time; In the scheduling state index table, a second check interval is determined based on the actual scheduling time, the first time delay and the second time delay, wherein the second check interval represents a potential conflict interval between the time when the user equipment initiates the uplink and the time when the user equipment schedules the downlink common channel; It is checked whether there is an identification bit representing an existing downlink common channel scheduling in the check interval; Correspondingly, if not, the uplink is scheduled at the target time, including: If there is no identification bit in the second check interval, the uplink is scheduled at the target time.

8. The method of claim 1, wherein, It further includes: Every preset period, the service area information of the satellite is updated; Based on the updated service area information of the satellite, the round-trip time delay information is updated.

9. An uplink and downlink scheduling apparatus characterized by comprising: Applied to a base station, the base station is deployed on a satellite, including: The computing module is configured to acquire satellite position information, longitude and latitude information of a service area center, and size parameters of the service area; determine an angle offset of a user equipment based on the satellite position information, the longitude and latitude information, and the size parameters, wherein the angle offset is an angle between a position offset of the user equipment relative to the service area center projected on the surface of the earth and the earth center; calculate a transmission distance based on the angle offset and the satellite position information, and calculate round-trip delay information between the satellite and the user equipment based on the transmission distance; The checking module is configured to check whether a first link scheduling time of the user equipment and a second link scheduling time corresponding to time allocation information conflict based on the time allocation information and the round-trip delay information, wherein the first link scheduling time and the second link scheduling time are determined based on a constraint of link scheduling at a target time, the time allocation information is a scheduling state index table, the scheduling state index table is a bitmap data structure used to record whether there is a scheduling task at a specific time, and a length of the bitmap data corresponds to a time unit within a target time range. The scheduling module is configured to schedule uplink and downlink at the target time if the answer is no, wherein the time allocation information is used to represent a time at which the user equipment performs a scheduling task.

10. A computing device, comprising: Comprising: a memory and a processor; The memory is used to store computer programs / instructions, and the processor is used to execute the computer programs / instructions, which realize the steps of the uplink and downlink scheduling method in any one of claims 1-8 when executed by the processor.

11. A computer readable storage medium, characterized in that, It stores computer programs / instructions, which realize the steps of the uplink and downlink scheduling method in any one of claims 1-8 when executed by the processor.

12. A computer program product, characterised in that, It comprises computer programs / instructions, which realize the steps of the uplink and downlink scheduling method in any one of claims 1-8 when executed by the processor.

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