Method for carrying out paging service in NTN NB-IOT network

Abstract

The invention relates to the technical field of communication, and discloses a method for performing paging service in an NTN NB-IOT network, comprising the following steps: S1, a core network acquires and stores terminal position information; s2, the core network calculates a paging time window Tpagi ng according to the terminal position, the base station paging cycle and ephemeris information, and screens out a target base station capable of covering the terminal; s3, the core network calculates the paging sending time of each base station, and selects a proper base station to send a message; s4, the core network calculates paging advance, and base station selection and message sending are completed; and S5, according to the received paging message and the configured parameters, the target base station sends the paging message to the terminal at a specified opportunity of the air interface. By combining intelligent data processing, optimization algorithm design and a distributed computing architecture, an efficient, accurate and safe technical scheme is formed, the response speed is increased, the processing precision is enhanced, human errors are eliminated, and then the working efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and specifically to a method for paging services in an NTN NB-IoT network. Background Art

[0002] Currently, NTN NB-IoT networks are widely used in the field of communication to support the connection of Internet of Things devices under low-power wide-area networks (LPWAN). The paging function of NTN NB-IoT networks is a key technology to ensure that devices can access the network in a timely manner and communicate effectively with base stations. In existing technical solutions, paging services usually rely on traditional centralized network architectures and combine timed scheduling and rule-driven to handle device access and communication. However, most existing paging methods are based on static scheduling strategies, and there will still be certain problems when high-density devices access.

[0003] Although existing NTN NB-IoT paging services support the access of low-power devices to a certain extent, they are insufficient in adaptability in a dynamic environment. With the increase in the number of devices and the change of network requirements, traditional static paging mechanisms are prone to waste of network resources and device access failures. Due to the lack of efficient real-time data analysis and processing capabilities in existing systems, paging conflicts and data loss are more serious when facing high-density devices or bursty traffic, which in turn affects the stability of the network and the reliability of communication. Such problems have a greater impact on paging efficiency and device access experience. Therefore, existing technical solutions need to be further optimized to ensure stability and efficiency in complex environments. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention provides a method for paging services in an NTN NB-IoT network, which solves the problems of paging conflicts, data loss, and insufficient adaptability of traditional paging mechanisms under high-density device access and dynamic environment changes.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A method for paging services in an NTN NB-IoT network, comprising the following steps:

[0006] S1. The core network obtains and stores the location information of the target terminal;

[0007] S2. When the target terminal is in an idle state, the core network calculates the paging time window Tpaging according to the terminal location, the base station paging period, and the ephemeris information, and screens out a set of target base stations that can cover the terminal within the Tpaging time;

[0008] S3. The core network calculates the paging transmission time of each base station based on the target base station set, and selects the base stations that can meet the paging scheduling to send paging messages;

[0009] S4. The core network calculates the paging advance Tmarg i n for each target base station, and completes base station selection and paging message distribution within Tmarg i n;

[0010] S5. The target base station calculates according to the received paging message and the locally configured paging parameters, and sends the paging message to the terminal at a specified time on the air interface.

[0011] Preferably, in step S1, after the terminal accesses the network, the core network obtains the current location information of the target terminal through the location registration information reported by the terminal and through the positioning function, and stores or updates this location information.

[0012] Preferably, in step S1, the core network re-obtains the location information of the terminal according to the new access request and the mobility update request of the target terminal, and replaces the original stored location information.

[0013] Preferably, in step S2, the core network uses the paging parameters of the terminal's current state. If the terminal is in the eDRX mode, it uses the terminal's eDRX high-layer period TeDRX_H as Tpagi ng; if it is in the DRX mode, it uses its DRX period Tdrx as Tpagi ng.

[0014] Preferably, in step S2, the core network combines the Tpagi ng duration, the terminal location, and the satellite ephemeris information to screen out all NTN base stations that can cover the terminal within the Tpagi ng time, and forms a target base station set.

[0015] Preferably, in step S3, the core network calculates the paging effective time period T1pagi ng_n for each base station in the target base station set respectively, and selects the maximum value T1pagi ng_max among them to control the duration of this round of paging.

[0016] Preferably, in step S3, if the terminal has not accessed within the T1pagi ng_max time, the core network re-screens the base station set that does not belong to the target base station set of the previous round, recalculates the corresponding T2pagi ng, and performs a new round of paging distribution on the premise that the sum of the current time and T2pagi ng is less than T1pagi ng_max, and repeats this process until the terminal accesses.

[0017] Preferably, in step S4, before sending the paging message, the core network calculates the paging advance of the paging message for each target base station respectively, and the specific formula is as follows:

[0018] T margin = T1 + T2 + T3;

[0019] Among them, T1 is the time required for the core network to calculate the appropriate paging opportunity from the terminal access; T2 is the link transmission delay from the core network initiating the paging message to the target base station receiving the message; T3 is the reserved redundant time for coping with unforeseen factors such as system delay and signal attenuation.

[0020] Preferably, in step S4, the core network associates and matches the terminal location with the satellite ephemeris information to determine the set of satellites that can cover the terminal within the Tpaging time, and further determines the NTN base stations deployed on these satellites as the final target base stations for paging scheduling.

[0021] Preferably, in step S5, the paging parameters include the paging time window PTW, the superframe number HF, the paging frame number PF, and the paging opportunity PO.

[0022] The present invention provides a method for paging services in an NTN NB-IOT network. It has the following beneficial effects:

[0023] 1. By combining intelligent data processing, optimized algorithm design, and a distributed computing architecture, the present invention forms an efficient, accurate, and secure technical solution. First, by using intelligent data processing technology, the system can quickly and real-time analyze massive amounts of data, not only improving the response speed but also enhancing the processing accuracy. Compared with the existing manual data processing methods, this automated data processing method eliminates human errors and improves work efficiency.

[0024] 2. By introducing a distributed computing architecture, the present invention can share the computing tasks among multiple nodes, significantly improving the processing capacity and system stability. Compared with the traditional centralized computing method, the present invention breaks through the computing bottleneck. It not only operates efficiently under high load but also ensures that the system can still respond smoothly under high load, avoiding performance degradation.

[0025] 3. By optimizing the algorithm design, the present invention realizes a more accurate prediction function, significantly enhancing the adaptability of the system in complex environments. Compared with the fixed-rule prediction methods in the prior art, it solves the problem that they cannot be adjusted in a timely manner in a dynamic environment, making the prediction results more in line with actual needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the flowchart of the method steps of the present invention;

[0027] Figure 2 is the schematic diagram of the operation logic of the present invention;

[0028] Figure 3 This is the distribution diagram of the base station, terminal and core network of the present invention. Specific implementation manners

[0029] Next, in combination with the accompanying drawings of the present invention specification, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0030] Please refer to the appended Figure 1 - appended Figure 3 , the embodiments of the present invention provide a method for paging services in an NTN NB-IoT network, including the following steps:

[0031] S1. The core network obtains and stores the location information of the target terminal;

[0032] Specifically, first, after receiving the access request of the target terminal, the core network starts to process the location information of the terminal. In the NB-IoT network, the terminal usually participates in communication in the idle state, and its location data is crucial for the subsequent paging process. Generally, the core network initially obtains the location information reported by the terminal accessing the network. According to different network architectures and communication protocols, the location can be obtained in different ways. In some embodiments, the core network can determine the approximate location of the terminal through the location information report of the terminal, such as using the location information reporting function of the terminal or through the positioning service of the base station. As an option, the core network can also directly obtain the accurate location of the terminal by means of its built-in positioning function. The positioning information can include information such as longitude, latitude, altitude, or location information obtained by other positioning technologies (such as satellite positioning, base station positioning, etc.).

[0033] Specifically, in a possible implementation manner, the core network will confirm the location of the terminal through the location information included in the uplink signaling of the terminal or through other auxiliary means within the network (such as base station ranging, triangulation positioning, etc.). When the terminal accesses the network, it sends the location information of its current location to the core network. After receiving this information, the core network stores the location data of the target terminal in its location management database based on this location information.

[0034] In some embodiments, the core network periodically updates the location information of each terminal. At this time, the location information of the terminal is updated as its location in the network changes. For example, when the terminal moves, the core network receives new location information and replaces the old location data in the storage. It should be noted that this location update strategy ensures the timeliness of the terminal location data, so that in subsequent paging and communication processes, the core network can accurately select a suitable base station for the terminal to communicate.

[0035] In a possible implementation, the core network optimizes the paging process through the update of location information. Especially when the terminal is in different network areas, the core network can timely adjust the selection range of the target base station. In this way, the location information of the terminal not only ensures the accuracy in the paging process, but also improves the utilization efficiency of network resources and avoids unnecessary repeated paging.

[0036] According to the present invention, after receiving the location information of the terminal, the core network can further perform other additional processing using this location information. For example, when selecting a target base station based on satellite information, the core network can combine satellite ephemeris information to ensure that the selected base station matches the location of the terminal, so as to optimize communication quality and delay.

[0037] Another possible implementation is that when the terminal first accesses the network, the core network first obtains the preliminary location of the terminal through simple positioning means (such as base station identification, access point, etc.). If more accurate location information is needed, the core network can request the terminal to provide more accurate location information, or further confirm the accurate location of the terminal by using advanced positioning technologies (such as multi-base station measurement, GPS positioning, etc.).

[0038] For example, in some cases, the update frequency of the terminal's location information may be dynamically adjusted according to the mobility of the terminal. If the terminal is in a high-speed moving state, the update frequency of the location information may be higher; while when the terminal is in a stationary or low-speed moving state, the update frequency of the location information can be appropriately reduced to reduce the network load.

[0039] Generally speaking, the implementation of step S1 ensures the real-time update and accurate storage of the terminal location information, which provides reliable basic data for base station selection, paging time calculation, etc. in subsequent steps.

[0040] S2. When the target terminal is in the idle state, the core network calculates the paging time window Tpaging according to the terminal location, base station paging cycle and ephemeris information, and screens out the set of target base stations that can cover the terminal within the Tpaging time;

[0041] Specifically, in step S2, the core network calculates the required Tpaging time window based on the terminal location information and ephemeris information obtained in the foregoing steps. The core network determines the final paging time window by combining the paging cycle of the base station, the idle state of the terminal, and the ephemeris information.

[0042] In this embodiment, the core network further filters out those base stations that can cover the terminal within the Tpaging time according to the actual location of the terminal and the current wireless coverage area. In this way, the core network effectively limits the set of base stations that need to participate in paging, thereby optimizing the resource scheduling in the paging process.

[0043] Generally, when the terminal is in the idle state, the core network performs Tpaging calculation according to the preset time slots and periodic scheduling strategies. This calculation not only involves the setting of the time window, but also includes the consideration of the signal coverage range of each base station to ensure that the target terminal can correctly receive the signal when the paging opportunity arrives. Specifically, the core network first combines the terminal location information and the ephemeris data of the base station to evaluate whether each base station has the ability to cover the terminal within the Tpaging time.

[0044] In a possible implementation, the core network uses Tdrx (the DRX cycle of the terminal) and TeDRX_H (the eDRX high-layer cycle of the terminal) as input parameters to accurately calculate Tpaging. If the terminal is in the eDRX mode, the core network calculates Tpaging according to the TeDRX_H cycle. On the contrary, if the terminal is in the traditional DRX mode, Tdrx is used as the calculation basis.

[0045] As an option, the core network can also dynamically adjust the Tpaging value according to the current time and the predicted change in the terminal location. If the terminal moves at a high speed, the core network will increase the flexibility of Tpaging to ensure that the paging time can cover the current location of the terminal.

[0046] Furthermore, the core network matches the current location of the terminal with the corresponding base station location. If the base station cannot cover the terminal within the Tpaging time window, the system will remove the base station from the candidate base station set. Through this mechanism, the core network can ensure that only those base stations with coverage capabilities within the correct time are selected.

[0047] Specifically, the core network evaluates each base station based on a location matching algorithm. The evaluation process takes into account factors such as the antenna direction of the base station, the coverage area, and possible signal attenuation, which will directly affect whether the base station can successfully send a paging message within the Tpaging window.

[0048] In addition, the core network will further adjust the selected set of base stations by combining the real-time status information of the terminal and ephemeris data. If the terminal undergoes a significant change in location, the core network will re-evaluate and screen the base stations to ensure the accuracy and timeliness of paging.

[0049] For example, in some embodiments, the core network performs multiple rounds of screening and calculation according to the foregoing method to ensure that the selected base stations can not only cover the terminal within the calculated Tpaging window, but also effectively meet the access requirements of the terminal in actual situations.

[0050] In this way, the Tpaging calculation method described in this embodiment can dynamically adjust the base station selection strategy, further improve the efficiency of the paging process, and ensure that the terminal can receive the paging message at the optimal time.

[0051] S3. The core network calculates the paging transmission time of each base station based on the target base station set, and selects the base stations that can meet the paging scheduling to send paging messages;

[0052] Specifically, in step S3, the core network further calculates the paging transmission time of each base station based on the target base station set screened in the foregoing steps. By accurately calculating the transmission timing of these base stations, the core network can ensure that paging messages are sent to the terminal at the correct time.

[0053] In this embodiment, the core network calculates for each eligible target base station to determine the specific time at which it can successfully initiate paging within the Tpaging time window. The calculation of this time depends not only on the time parameters of Tpaging, but also on factors such as the current network load, the transmission capacity of the base station, and signal attenuation. Specifically, the paging transmission time of the base station is adjusted according to Tpaging and the coverage range of the base station, and the core network uses this mechanism to ensure that paging messages can be transmitted to the target terminal in a timely and accurate manner.

[0054] Generally, the core network calculates the paging transmission time T of the base station through the following formula send :

[0055] T send = T start +ΔT paging ;

[0056] where, T send is the feasible paging start time calculated by the core network; ΔT paging is the delay required for the base station to send a paging message, including signal propagation delay, base station scheduling delay, etc.

[0057] During the calculation process, the core network not only considers the delay of physical transmission but also makes appropriate adjustments according to factors such as network load to avoid signal overlap or interference.

[0058] As an option, the core network can also be optimized in different network environments. For example, in some high-load scenarios, the core network can preferentially select a base station closer to the terminal to send paging, thereby reducing the signal propagation delay. Specifically, in some embodiments, the core network will select the optimal base station for paging operations according to the relative position relationship between the base station and the terminal. This optimization not only improves the paging efficiency but also effectively avoids paging failures caused by excessive transmission delays of remote base stations.

[0059] In a possible implementation, the core network will also comprehensively consider multiple factors to optimize the paging sending time. In addition to considering the calculation result of Tpaging, the core network may also predict the access time window of the terminal based on historical data, thereby reserving sufficient paging opportunities. This prediction mechanism can help the core network better manage network resources and ensure that all paging operations are completed within a limited time.

[0060] For example, assume that at a certain moment, the core network determines the best time to send a paging message according to the Tpaging time window and the position relationship of the base station. If this time conflicts with the paging sending times of other base stations, the core network will readjust the sending time to avoid conflicts. To this end, the core network will dynamically adjust ΔT_paging to ensure that the paging sending times of each base station are as evenly distributed as possible, thereby reducing conflicts and interference.

[0061] In addition, in some embodiments, the core network can also adjust the paging sending time according to the idle state of the terminal. If the terminal is in a low-power state or has special scheduling requirements, the core network will adapt according to these factors to optimize the paging sending time. In this way, the core network can further improve the accuracy of paging and effectively reduce the occurrence of invalid paging.

[0062] Generally speaking, the core idea of step S3 is to calculate the most suitable paging time based on Tpaging and the coverage area of the base station, so as to ensure that the base station sends a paging message to the target terminal at the appropriate moment. Through this precise calculation process, the core network can greatly improve the success rate of the paging process and reduce resource waste caused by inappropriate timing.

[0063] S4. The core network calculates the paging advance Tmargin for each target base station and completes base station selection and paging message distribution within Tmargin;

[0064] Specifically, in step S4, the core network further calculates the paging advance Tmargin based on the previously calculated paging transmission time and the selection result of the target base station. This advance is a key parameter to ensure that the paging message can be successfully sent to the target base station and transmitted at an appropriate time.

[0065] In this embodiment, the calculation of Tmargin takes into account multiple factors, including the transmission delay of the base station, the update period of ephemeris information, the timeliness of location updates, etc. Specifically, the calculation formula of Tmargin is as follows:

[0066] T margin = T1 + T2 + T3;

[0067] Wherein, T1 is the time required for the core network to calculate the appropriate paging opportunity from the terminal access; T2 is the link transmission delay from the core network initiating the paging message to the target base station receiving the message; T3 is the reserved redundant time to cope with unforeseen factors such as system delay and signal attenuation.

[0068] Generally, the calculation of Tmargin is not just a simple accumulation of time. The core network will dynamically evaluate various changing factors in the network environment and adjust the size of Tmargin accordingly. For example, if the network load is high, the core network may need to increase the redundant time T3 to ensure the reliability of paging. In some high-load network environments, T3 may be appropriately increased to prevent paging failures caused by network congestion.

[0069] Specifically, the reasonable setting of Tmargin can effectively avoid timing conflicts generated during multi-base station coordinated paging. To ensure that the target base station can complete the transmission of the paging message in a timely manner, the core network needs to adjust Tmargin according to the load conditions and propagation conditions of the base station before each round of paging. In this way, the core network can achieve the smooth transmission of the paging message under strict timing control.

[0070] As an option, the core network can combine the idle period of the terminal, the load conditions of the base station, and other network parameters to adjust the value of Tmargin in real time. For example, during idle periods, the response speed of the terminal is faster, and Tmargin can be set to a smaller value; while during high-load or high-traffic periods, Tmargin should be appropriately increased to ensure the stability of signal transmission.

[0071] In a possible implementation, the calculation of Tmargin is not limited to the physical layer latency, but also includes the scheduling delay of the protocol stack. These delays mainly come from the signaling interaction process between the core network and the base station. For example, the synchronization mechanism between the terminal and the base station, the configuration of radio interface parameters, etc. In these embodiments, Tmargin will be considered as a composite parameter, depending not only on the latency of physical transmission, but also taking into account various additional delays in the network protocol stack.

[0072] For example, in some embodiments, if the terminal is in different eDRX modes, the core network may adjust the size of Tmargin according to the terminal's eDRX cycle TeDRX_H. Since the terminal is in a deep sleep state in the eDRX mode, the transmission of paging messages may be affected. Therefore, the core network needs to reserve more time for such situations to ensure the success of paging.

[0073] Furthermore, the calculation of Tmargin should also consider the update frequency of ephemeris information. In some cases, the delay of ephemeris update may cause a deviation in the time window of paging messages. Therefore, the core network will also adjust Tmargin in a timely manner according to the timeliness of ephemeris update to ensure the accuracy of paging timing.

[0074] In addition, in some embodiments, if the distance to the target base station is far or it is in the edge area of the network, the value of Tmargin may increase accordingly. This is because the transmission latency of long-distance signals is long and may be affected by strong signal attenuation. By appropriately increasing Tmargin, the core network can ensure that the remote base station can also send paging messages within the predetermined time.

[0075] After completing the calculation of Tmargin, the core network will complete the final selection of the base station according to the calculated result and send the paging message to the target base station within Tmargin. The successful completion of this process is the key to ensuring that the terminal can receive the paging message in time.

[0076] S5. The target base station calculates and sends a paging message to the terminal at a specified timing on the radio interface according to the received paging message and the locally configured paging parameters.

[0077] Specifically, in step S5, the target base station calculates the accurate transmission timing of the paging message according to the paging message sent by the core network in the previous step and in combination with the locally configured paging parameters. This calculation process is the key to the successful sending of the paging message from the base station to the terminal.

[0078] In this embodiment, the target base station calculates the specific transmission time based on parameters such as the paging time window (Tpaging), hyperframe number (HF), paging frame number (PF), and paging occasion (PO) in the received paging message. The task of the base station is to ensure that the paging message is sent within an appropriate time window so that the terminal can successfully receive the message.

[0079] Generally, the target base station combines the instructions from the core network and its local configuration and uses the following formula to calculate the specific paging transmission time:

[0080] T send = T current + ΔT paging ;

[0081] Where, T current is the current time of the base station; ΔT paging is the transmission delay of the paging message, including the scheduling delay of the base station, signal propagation delay, etc.

[0082] In this formula, the base station first obtains the current system time T current , and then calculates the specific transmission time according to the paging occasion parameters sent by the core network. The calculation of ΔT paging usually includes the signaling transmission delay from the core network to the base station and the scheduling delay of the base station for the air interface.

[0083] Specifically, the base station needs to dynamically adjust the transmission time of the paging message according to multiple parameters. For example, if the base station is far from the terminal or in the edge area of the network, ΔT_paging may increase. This is because a longer distance usually causes signal attenuation or propagation delay, so the base station needs to reserve more time to send the paging message before the scheduled time.

[0084] As an option, the base station also adjusts the paging occasion according to the idle period and DRX mode of the terminal. If the terminal is in a deep sleep state (such as in the eDRX mode), the base station may increase the waiting time to ensure that the paging message can reach the terminal smoothly and be correctly received.

[0085] Specifically, if the terminal is in the eDRX mode, the base station will calculate an adjusted transmission time according to the DRX parameters and eDRX period of the terminal, which can avoid missing the paging message due to the terminal being in a deep sleep state.

[0086] In a possible implementation, the base station may also adjust the calculation of the paging occasion according to air interface parameters (such as PTW, HF, PF, PO). Each parameter has a direct impact on the transmission time of the paging message. For each round of paging, the base station accurately calculates the message transmission time according to these parameters, so as to ensure that the message can cover all target terminals.

[0087] For example, if multiple terminals are within the range of the same base station, the base station will calculate different paging times for each terminal and avoid interference by coordinating time slots. This time slot coordination can be adjusted based on the idle period of the terminal, the paging time window, and the resource status of the base station.

[0088] For example, if the base station finds that the DRX cycle of a certain terminal is different from that of other terminals, the base station will adjust the paging time to ensure that paging is performed during the idle period of the terminal. This adjustment mechanism can effectively reduce paging conflicts and improve the success rate of paging.

[0089] By this method, the base station can not only ensure the accuracy of the paging occasion, but also improve the utilization efficiency of network resources and avoid waste of resources. Especially in the case of high network load, the base station needs to flexibly adjust the transmission time according to the time slot scheduling and the idle state of the terminal to maximize the system performance.

[0090] In some embodiments, the base station can also adjust the transmission power of paging according to the current network state and transmission quality. If the network signal strength is insufficient or there is interference, the base station may increase the transmission power to ensure that the paging message can cover the terminal.

[0091] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for paging service in an NTN NB-IOT network, characterized in that, It includes the following steps: S1. The core network obtains and stores the location information of the target terminal; S2. When the target terminal is in the idle state, the core network calculates the paging time window Tpaging based on the terminal location, base station paging cycle, and ephemeris information, and filters out the set of target base stations that can cover the terminal within the Tpaging time; S3. The core network calculates the paging transmission moment of each base station based on the set of target base stations, and selects the base stations that can meet the paging scheduling to send paging messages; S4. The core network calculates the paging advance amount Tmargin for each target base station, and completes the base station selection and paging message distribution within Tmargin; S5. The target base station calculates according to the received paging message and the locally configured paging parameters, and sends the paging message to the terminal at the specified timing on the air interface.

2. The method for performing a paging service in an NTN NB-IoT network according to claim 1, wherein In step S1, after the terminal accesses the network, the core network obtains the current location information of the target terminal through the location registration information reported by the terminal and through the positioning function, and stores or updates this location information.

3. A method for paging service in an NTN NB-IoT network according to claim 1, characterized in that, In step S1, the core network re-obtains the location information of the terminal according to the new access request and mobile update request of the target terminal, and replaces the original stored location information.

4. A method for paging service in an NTN NB-IoT network according to claim 1, characterized in that, In step S2, according to the paging parameters of the current state of the terminal, if the terminal is in the eDRX mode, the eDRX high-layer period TeDRX_H of the terminal is used as Tpaging; if it is in the DRX mode, its DRX period Tdrx is used as Tpaging.

5. A method for paging service in an NTN NB-IoT network according to claim 1, characterized in that, In step S2, the core network combines the Tpaging duration, terminal location, and satellite ephemeris information to filter out all NTN base stations that can cover the terminal within the Tpaging time, forming a set of target base stations.

6. A method for paging service in an NTN NB-IoT network according to claim 1, characterized in that, In step S3, the core network calculates the paging effective time period T1paging_n of each base station for the set of target base stations respectively, and selects the maximum value T1paging_max among them to control the duration of this round of paging.

7. A method for paging service in an NTN NB-IoT network according to claim 1, characterized in that, In step S3, if the terminal still has not accessed within the T1paging_max time, the core network re-filters the set of base stations that do not belong to the set of target base stations in the previous round, recalculates the corresponding T2paging, and performs a new round of paging distribution on the premise that the sum of the current moment and T2paging is less than T1paging_max, repeating this process until the terminal accesses.

8. A method for paging service in an NTN NB-IoT network according to claim 1, characterized in that In step S4, before sending the paging message, the core network calculates the advance amount of the paging message for each target base station respectively, and the specific formula is as follows: T margin = T1 + T2 + T3; Where, T1 is the time required for the core network to calculate the appropriate paging timing from the terminal access; T2 is the link transmission delay from the core network initiating the paging message to the target base station receiving the message; T3 is the reserved redundant time for dealing with unforeseen factors such as system delay and signal attenuation.

9. A method for paging service in an NTN NB-IOT network according to claim 1, characterized in that, In the step S4, the core network performs associated matching through the terminal location and satellite ephemeris information, determines the set of satellites that can cover the terminal within the Tpaging time, and further determines the NTN base stations deployed on the satellites as the final target base stations for paging scheduling.

10. A method for paging service in an NTN NB-IoT network according to claim 1, characterized in that, In the step S5, the paging parameters include a paging time window PTW, a superframe number HF, a paging frame number PF, and a paging occasion PO.

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