A method and related equipment for enhancing communication coverage in non-terrestrial networks

Abstract

This invention discloses a method, apparatus, and storage medium for enhancing communication coverage in non-terrestrial networks. The method includes steps such as determining a target coverage level and physical layer parameter combinations based on service type and relative location information, and generating a coverage enhancement strategy based on the physical layer parameter combinations. This invention enables a cross-layer dynamic coordination of multiple physical layer parameters in a coverage enhancement strategy. This reduces resource conflicts caused by the independent implementation of multiple single physical layer parameter coverage enhancement strategies, alleviates the difficulty of simultaneously meeting different needs with limited wireless resources, and enhances communication stability in non-terrestrial network scenarios. This invention has wide applications in the field of non-terrestrial network communication technology.

Description

Technical Field

[0001] This invention relates to the field of non-terrestrial network communication technology, and in particular to a method and related equipment for enhancing communication coverage in non-terrestrial networks. Background Technology

[0002] In non-terrestrial networks employing advanced wireless communication technologies (such as 5G or 6G), which typically utilize communication satellites for network construction, enhanced communication coverage is essential. This involves employing various optimization techniques to improve satellite signal coverage across geographical areas, service quality, and connection reliability. This addresses signal blind spots, weak coverage, or service interruptions caused by path loss, congestion effects, and resource constraints in satellite communication, thereby expanding the effective service area, improving edge signal quality, and ensuring highly reliable connections. However, due to the high-speed mobility of communication satellites (e.g., LEO orbital speed > 7 km / s) and large satellite-to-ground loopback delays (single-hop delay ≥ 5 ms), edge user terminals are prone to encountering periodic coverage gaps, rendering traditional terrestrial network coverage enhancement mechanisms ineffective. Summary of the Invention

[0003] In view of the technical problems of high latency and limited resources of satellite-to-ground links in non-terrestrial networks, and the poor effectiveness of traditional coverage enhancement mechanisms, the present invention aims to provide a communication coverage enhancement method, apparatus and storage medium for non-terrestrial networks.

[0004] On one hand, embodiments of the present invention include a method for enhancing communication coverage for non-terrestrial networks, the method comprising the following steps:

[0005] To obtain the service types of communication services provided by non-terrestrial networks to user terminals;

[0006] The relative position information between the first base station in the non-terrestrial network and the user terminal is obtained; the first base station is a base station that can establish a communication connection with the user terminal at a future time.

[0007] The target coverage level is determined based on the service type and the relative location information;

[0008] Based on the target coverage level, a combination of physical layer parameters is determined; the combination of physical layer parameters includes one or more physical layer parameters.

[0009] Based on the combination of physical layer parameters, a coverage enhancement strategy is generated;

[0010] Execute the coverage enhancement strategy.

[0011] Further, obtaining the relative position information between the first base station in the non-terrestrial network and the user terminal includes:

[0012] Obtain the ephemeris information of the first base station;

[0013] Based on the ephemeris information, determine the sub-satellite point coordinates and altitude of the first base station at the future time;

[0014] Predict the latitude and longitude of the user terminal at the future time;

[0015] Based on the coordinates, altitude, and latitude and longitude of the satellite nadir point, determine the elevation angle and distance of the first base station relative to the user terminal at a future time;

[0016] The elevation angle and the distance are used as the relative position information.

[0017] Further, determining the target coverage level based on the service type and the relative location information includes:

[0018] Obtain the business priority index corresponding to the business type;

[0019] A first weight, a second weight, and a third weight are defined; the first weight corresponds to the business priority index, the second weight corresponds to the elevation angle, and the third weight corresponds to the distance.

[0020] Based on the first weight, the second weight, and the third weight, the business priority index, the elevation angle, and the distance are weighted and summed.

[0021] The target coverage level is determined based on the weighted summation result, in a positive correlation.

[0022] Further, determining the combination of physical layer parameters based on the target coverage level includes:

[0023] When the target coverage level is high, configure PDCCH repetition to be activated and Msg4 to be configured with the maximum number of repetitions to obtain the physical layer parameter combination.

[0024] When the target coverage level is medium, configure the SSB cycle and configure the triggering of SIB1 repeated linkage to obtain the physical layer parameter combination;

[0025] When the target coverage level is low, configure the SSB cycle to obtain the physical layer parameter combination.

[0026] Further, determining the combination of physical layer parameters based on the target coverage level includes:

[0027] Obtain parameters for multiple candidate physical layers;

[0028] Obtain the conflict level between any two candidate physical layer parameters when performing the aforementioned service type;

[0029] Based on the target coverage level, the conflict level is determined in a negative correlation;

[0030] The combination of physical layer parameters is determined based on the two candidate physical layer parameters having the determined conflict level.

[0031] Furthermore, obtaining the conflict level between any two candidate physical layer parameters when performing the aforementioned service type includes:

[0032] For any two candidate physical layer parameters, obtain the time-domain conflict index, frequency-domain conflict index, and power conflict index between the two candidate physical layer parameters when performing the service type.

[0033] The conflict level is determined based on the time-domain conflict index, the frequency-domain conflict index, and the power conflict index.

[0034] Further, determining the conflict level based on the time-domain conflict index, the frequency-domain conflict index, and the power conflict index includes:

[0035] Based on the first weight, set the weights corresponding to the time-domain conflict index and the frequency-domain conflict index;

[0036] Based on the second weight and the third weight, the weight corresponding to the power conflict index is set;

[0037] The time-domain conflict index, the frequency-domain conflict index, and the power conflict index are weighted and summed.

[0038] The conflict level is determined based on the weighted summation result, in a positive correlation.

[0039] Further, executing the coverage enhancement strategy includes:

[0040] Obtain capability indication information reported by the user terminal; the capability indication information indicates the user terminal's support capability for the coverage enhancement strategy.

[0041] When the capability indication information meets the judgment conditions, the coverage enhancement strategy is sent to the first base station;

[0042] Obtain the base station configuration information returned by the first base station; the base station configuration information is generated by the first base station in response to the coverage enhancement strategy;

[0043] The base station configuration information is sent to the second base station and then forwarded to the user terminal; the second base station is the base station currently establishing a communication connection with the user terminal.

[0044] The user terminal is triggered to perform a pre-adjustment based on the base station configuration information;

[0045] The communication connection of the user terminal is switched from the second base station to the first base station.

[0046] On the other hand, embodiments of the present invention also include a computer device, including a memory and a processor, the memory for storing at least one program, and the processor for loading at least one program to execute the communication coverage enhancement method for non-terrestrial networks in the embodiments.

[0047] On the other hand, embodiments of the present invention also include a computer-readable storage medium storing a processor-executable program, which, when executed by a processor, is used to perform the communication coverage enhancement method for non-terrestrial networks in the embodiments.

[0048] The beneficial effects of the present invention are as follows: The communication coverage enhancement method for non-terrestrial networks in the embodiments defines the target coverage level by the core network of the non-terrestrial network through global coordination, based on factors such as service requirements represented by service type and relative position information between user terminals and base stations, and generates the combination of physical layer parameters to be used for coverage enhancement strategy according to the target coverage level. This realizes a coverage enhancement strategy with cross-layer dynamic coordination of multiple physical layer parameters, which helps to reduce resource conflicts caused by the independent implementation of multiple single physical layer parameter coverage enhancement strategies, alleviates the difficulty of limited wireless resources to meet different needs at the same time, and thus enhances communication stability in non-terrestrial network scenarios. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of a non-terrestrial network to which the communication coverage enhancement method for non-terrestrial networks can be applied in the embodiments;

[0050] Figure 2 This is a schematic diagram illustrating the steps of a communication coverage enhancement method for non-terrestrial networks in an embodiment.

[0051] Figure 3 This is a flowchart illustrating steps S601-S606 in the embodiment.

[0052] Figure 4 This is a flowchart illustrating steps S601-S606 in the embodiment. Detailed Implementation

[0053] Terminology Explanation:

[0054] Non-terrestrial Network (NTN) is one of the technological directions for direct satellite connection between mobile phones and satellites.

[0055] SSB: Synchronization Signal Block, which includes the Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), and Physical Broadcast Channel (PBCH), is the basis for time and frequency synchronization when a terminal accesses the network. Each SSB corresponds to a certain period. If the period is fixed (e.g., 5ms), it will be difficult to adapt to the multi-band and multi-scenario requirements of 5G non-terrestrial networks. Therefore, 3GPP introduced a configurable SSB period, that is, the SSB period is a configurable physical layer parameter.

[0056] PDCCH: Physical Downlink Control Channel. If PDCCH repetition is activated, the base station can repeatedly transmit the same PDCCH scheduling information (such as Downlink Control Information, DCI) in multiple consecutive subframes (typical repetition count: 4 / 8 / 16 / 32 times). The user terminal accumulates and decodes the repetitive signals through soft combining, which can improve the signal-to-noise ratio and compensate for path loss. In other words, PDCCH repetition (activated or inactive) is a configurable physical layer parameter.

[0057] Msg4: In 5G / NR-based mobile communication systems, Msg4 is the fourth message in the Contention-Based Random Access (CBRA) procedure. Its core function is to resolve access conflicts among multiple user terminals and confirm the establishment or restoration of RRC connections. In weak signal environments such as non-terrestrial networks, base stations can improve reception success rates by repeatedly transmitting Msg4 to user terminals. The number of repetitions is dynamically configured by SIB or DCI (e.g., indicated by the MCS field of DCI 1_0), thereby compensating for path loss. In other words, the number of Msg4 repetitions is a configurable physical layer parameter.

[0058] Although physical layer coverage enhancement techniques based on physical layer parameters such as SSB, PDCCH, and Msg4 can currently achieve SSB period extension to 160ms, Type-0 PDCCH cross-slot repetition, and Msg4 PDSCH multi-slot transmission, the following problems exist:

[0059] Strategy fragmentation: SSB period, PDCCH repetition, and Msg4 repetition are controlled by different modules, leading to resource conflicts. For example, although a long SSB period can reduce network search energy consumption, if the PDCCH repetition strategy is implemented simultaneously, the long SSB period will collide with the high-frequency PDCCH repetition (20ms period) in the time domain, resulting in 40% of the PDCCH candidate positions being occupied by SSB. Msg4 repetition and SIB1 PDSCH repetition use separate signaling (PBCH vs SIB1), and no joint scheduling window is established, causing the control channel and service channel gains to cancel each other out.

[0060] Rigid beam management: The SSB beam scanning period (≥80ms) and PDCCH repetition slots (X=1~4) lack a spatiotemporal alignment algorithm, which degrades the spatial isolation of the repetition signal by more than 6dB during satellite attitude maneuvers.

[0061] No service adaptation: Critical services such as emergency calls cannot be prioritized for coverage enhancement;

[0062] Handover interruption: When the satellite is switched, the coverage parameters of the target cell base station are not synchronized, which can easily lead to the failure of user terminal access.

[0063] Analysis of the above technical issues reveals that if multiple different physical layer parameters are used independently for coverage enhancement, policy conflicts may occur. However, if global dynamic coordination of different physical layer parameters such as SSB, PDCCH, SIB1, and Msg4 is achieved, a core network-driven joint control architecture for coverage enhancement can be constructed, enabling stable communication in non-terrestrial network communication scenarios.

[0064] Based on the above principles, this embodiment provides a communication coverage enhancement method for non-terrestrial networks. This communication coverage enhancement method for non-terrestrial networks can be applied to... Figure 1 In the non-terrestrial network shown. (Refer to...) Figure 1 The non-terrestrial network includes an OAM system, a UDM location database, a PCF policy layer, an AMF (Advanced Location Function), gNB1 (first base station), gNB2 (second base station), and a user terminal (UE). The OAM system, UDM location database, PCF policy layer, and AMF belong to the core network, which also includes components such as the SMF (Supervisory Management Function). gNB1 (first base station) and gNB2 (second base station) can be base stations installed on communication satellites or drones, etc. This embodiment uses a communication satellite as an example. The user terminal (UE) can be a user-held mobile phone or other terminal. In this embodiment, unless otherwise specified, the user terminal (UE) can refer to a specific terminal.

[0065] In this embodiment, gNB2 (the second base station) is the base station that the user terminal UE is currently accessing (when or before the execution of the communication coverage enhancement method for non-terrestrial networks), and gNB1 (the first base station) is the base station that the user terminal UE is expected to access at a future time T. gNB1 (the first base station) and gNB2 (the second base station) can be different base stations, meaning that the communication coverage enhancement method for non-terrestrial networks can be applied to coverage enhancement during base station handover; gNB1 (the first base station) and gNB2 (the second base station) can also be the same base station, meaning that the communication coverage enhancement method for non-terrestrial networks can also be applied to coverage enhancement during the process of the user terminal UE continuously connecting to a base station.

[0066] Reference Figure 2 The communication coverage enhancement method for non-terrestrial networks includes the following steps:

[0067] S1. Obtain the service type of communication services provided by the non-terrestrial network to the user terminal;

[0068] S2. Obtain the relative position information between the first base station and the user terminal in the non-terrestrial network;

[0069] S3. Determine the target coverage level based on the business type and relative location information;

[0070] S4. Determine the combination of physical layer parameters based on the target coverage level;

[0071] S5. Generate coverage enhancement strategies based on the combination of physical layer parameters;

[0072] S6. Implement coverage enhancement strategies.

[0073] In this embodiment, steps S1-S6 can be executed by the core network. For example, steps S1-S5 can be executed by the PCF policy layer in the core network, and step S6 can be executed by the AMF in the core network. Specifically, when the PCF policy layer executes steps S1-S5, it can also call the OAM system, UDM location database, and SMF in the core network.

[0074] In step S1, the PCF policy layer can invoke the SMF to detect the service type of the communication service currently provided to the user terminal by the non-terrestrial network. The SMF sends the specific details of the detected service type to the PCF policy layer. In this embodiment, the service type can specifically be eMBB, uRLLC, and mMTC, etc., and their characteristics are shown in Table 1.

[0075] Table 1

[0076] Business type Business flow characteristics Quality of Service (QoS) requirements Coverage priority eMBB Latency <1ms, reliability >99.999% 5 urgent uRLLC Peak speed >1Gbps 3 high mMTC Data packet < 200 bytes 1 Low

[0077] When the PCF policy layer executes step S2, which is to obtain the relative position information between the first base station and the user terminal in the non-terrestrial network, it can call the OAM system to obtain the ephemeris information of gNB1 (the first base station) and determine the sub-satellite point coordinates of gNB1 (the first base station) at a future time T based on the ephemeris information. and height h, where λ sat The longitude of the point beneath the star. The latitude of the point beneath the star.

[0078] When the PCF policy layer executes step S2, which is to obtain the relative position information between the first base station in the non-terrestrial network and the user terminal, it can predict the position of the user terminal UE, or have the user terminal UE report its position at a future time T, expressed as latitude and longitude. After obtaining the coordinates of the sub-satellite point Altitude h and latitude and longitude of user terminal (UE) Then, you can use the formula

[0079]

[0080] Calculate the elevation angle θ and distance d of gNB1 (the first base station) relative to the user terminal UE at a future time T. Here, R is the Earth's radius, a constant. The obtained elevation angle θ and distance d can be used as relative position information representing the relative positional relationship between gNB1 (the first base station) and the user terminal UE.

[0081] When the PCF policy layer executes step S3, which is to determine the target coverage level based on the service type and relative location information, it can first quantify the service type and relative location information. Specifically, for the service type, the service priority index P(f(QoS)) can be obtained as the quantified data. In this embodiment, the service priority index P can be set to be the same as the QoS requirements in Table 1. For example, for the eMBB service type, its service priority index P equals 3. Regarding the elevation angle θ in the relative location information, since the elevation angle θ is related to the communication loss between the user terminal UE and gNB1 (the first base station) (the smaller the elevation angle θ, the greater the loss), it can be calculated... As quantified data, where θ min Let θ be the minimum possible value; for the distance d in the relative position information, since a larger distance d indicates a larger path loss between the user terminal UE and gNB1 (the first base station), it can be calculated... As quantified data, where d max Let d be the maximum value that d can take.

[0082] When the PCF strategy layer executes step S3, which is to determine the target coverage level based on the service type and relative location information, it can set a first weight α corresponding to the service priority index P, a second weight β corresponding to the elevation angle θ, and a third weight γ corresponding to the distance d. In this embodiment, the second weight β and the third weight γ can generally be set to be equal so that each part of the relative location information has the same weight.

[0083] By performing step S3, the quantified data shown in Table 2 can be obtained.

[0084] Table 2

[0085] factor Quantitative data Weight Recommended values ​​for weights Business type f(QoS) First weight α 0.4 Elevation angle θ g(θ) Second weight β 0.3 Distance d h(d) Third weight γ 0.3

[0086] When the PCF strategy layer executes step S3, which is to determine the target coverage level based on the business type and relative location information, it can use the formula...

[0087] CoverageClass=α·f(QoS)+β·g(θ)+γ·h(d)

[0088] This allows for a weighted summation of the service priority index, elevation angle, and distance. In this embodiment, the result of the weighted summation can be used as the target coverage class, or the target coverage class can be determined in other ways to ensure a positive correlation between the target coverage class and the result of the weighted summation, such as multiplying the result of the weighted summation by a constant ratio to obtain the target coverage class.

[0089] In this embodiment, the target coverage level represents the signal coverage level that gNB1 (first base station) needs to achieve in order to ensure good communication quality between gNB1 (first base station) and the user terminal UE (UE) when the UE is performing a specific service and has specific relative location information with the core network. A higher target coverage level indicates a higher or stronger coverage level.

[0090] In this embodiment, when the PCF policy layer executes step S4, which is to determine the physical layer parameter combination based on the target coverage level, it can determine the physical layer parameter combination corresponding to each value range of the target coverage level by looking up a table. For example, referring to Table 3, when the value of the target coverage level CoverageClass is in the range of 4-5, the target coverage level CoverageClass is a high level. Then, the PCF policy layer will be able to find a specific physical layer parameter combination such as "activate PDCCH repetition and configure the maximum number of repetitions (e.g., 8 times) for Msg4".

[0091] Table 3

[0092]

[0093] In this embodiment, the physical layer parameter combinations in Table 3 (i.e., the specific types, numbers, and values ​​of the physical layer parameters included) can be determined through prior experiments by optimizing the values ​​of different target coverage classes (CoverageClass), thereby forming a fixed correspondence between the different values ​​of the target coverage class. Therefore, through the correspondence in Table 3, the optimized physical layer parameter combinations for the target coverage class can be obtained.

[0094] In this embodiment, the PCF policy layer can also dynamically determine the physical layer parameter combination when executing step S4. Specifically, when the PCF policy layer executes step S4, that is, the step of determining the physical layer parameter combination based on the target coverage level, it can perform the following steps:

[0095] S401. Obtain parameters for multiple candidate physical layers;

[0096] S402. Obtain the conflict level between any two candidate physical layer parameters under the given business type;

[0097] S403. Determine the conflict level negatively correlated with the target coverage level;

[0098] S404. Determine the combination of physical layer parameters based on two candidate physical layer parameters with the determined conflict level.

[0099] In step S401, the candidate physical layer parameters can be any of the physical layer parameters that may appear in Table 3, such as activating PDCCH repetition, configuring the maximum number of repetitions for Msg4, configuring the SSB cycle, configuring the triggering of SIB1 repetition linkage, etc. However, the correspondence between physical layer parameters and specific target coverage level values ​​has not yet been determined.

[0100] In step S402, all any two candidate physical layer parameters are traversed. For each pair of candidate physical layer parameters, the conflict level between the two candidate physical layer parameters is calculated under the business type determined in step S1.

[0101] Specifically, for any two candidate physical layer parameters, the temporal conflict index, frequency domain conflict index, and power conflict index between the two candidate physical layer parameters are obtained under the service type determined in step S1. In this embodiment, the temporal overlap coefficient of the two candidate physical layer parameters can be calculated as the temporal conflict index, the frequency band overlap coefficient of the two candidate physical layer parameters can be calculated as the frequency domain conflict index, and the power saturation of the two candidate physical layer parameters can be calculated as the power conflict index.

[0102] Specifically, this will be illustrated using two candidate physical layer parameters: "configure SSB cycle" and "activate PDCCH repetition." In this embodiment, the formulas are used to illustrate the concepts.

[0103]

[0104] Calculate the time overlap coefficient T overlap As a time-domain conflict indicator, F is used to calculate the frequency band overlap coefficient. overlap As a frequency domain conflict indicator, the power saturation P is calculated. saturation As an indicator of power conflict.

[0105] Among them, T SSB T represents the time slot length required to execute the "Configure SSB Cycle" function alone. PDCCH_rep T represents the time slot length required to execute "Activate PDCCH Repetition" alone. frame The frame length is represented by the calculated temporal overlap coefficient T. overlap This indicates the degree of slot resource conflict that occurs if "Configure SSB Cycle" and "Activate PDCCH Repetition" are executed simultaneously; RB SSB This indicates the number of RBs (Resource Blocks) required to execute the "Configure SSB Cycle" alone. PDCCH_rep This indicates the number of RBs required to execute "Activate PDCCH Repeat" alone. frame The number of RBs in a frame is used to calculate the frequency band overlap coefficient F. overlap This indicates the degree of frequency domain resource conflict that would result from simultaneously executing "Configure SSB Cycle" and "Activate PDCCH Repetition"; P SSB This indicates the base station power required to execute the "Configure SSB Cycle" function alone, P. PDCCH_rep This represents the base station power required to execute "Activate PDCCH Repetition" alone, P max The total power of the base station is represented by the calculated power saturation P. saturation This indicates the degree of power resource conflict that occurs if "Configure SSB Cycle" and "Activate PDCCH Repetition" are executed simultaneously.

[0106] In this embodiment, the time overlap coefficient T can be adjusted. overlap Frequency band overlap coefficient F overlap and power saturation P saturation Perform a weighted summation, and use the result of the weighted summation as the conflict level.

[0107] Specifically, the time overlap coefficient T overlap Frequency band overlap coefficient F overlap and power saturation P saturationThe weights can all be 1, meaning the time overlap coefficient T can be directly calculated. overlap Frequency band overlap coefficient F overlap and power saturation P saturation The sum obtained by adding them together is used as the conflict level.

[0108] In this embodiment, the first weight α can be used as the time overlap coefficient T. overlap (Time Domain Collision Index) and Band Overlap Coefficient F overlap The weights of the (frequency domain conflict index) are determined, with the second weight β (generally equal to the third weight γ) used as the power saturation P. saturation The weights of the (power conflict index) are weighted and summed to obtain the conflict level. The principle behind this is that time-domain conflict indexes and frequency-domain conflict indexes are usually related to service type, so they are given the same weight, i.e., the first weight α; power conflict indexes are usually related to relative position information such as elevation angle and distance, so they are given the same weight, i.e., the second weight β or the third weight γ.

[0109] In step S402, the conflict level between the two candidate physical layer parameters, "configure SSB period" and "activate PDCCH repetition", is calculated. Taking into account the conflicts between the two candidate physical layer parameters in terms of time slot resources, spectrum resources and power resources, it can quantify the size of resource conflicts caused by configuring these candidate physical layer parameters at the same time.

[0110] In step S402, for any other combination of two candidate physical layer parameters, the conflict level between them can be calculated using a similar formula.

[0111] In step S403, the conflict level is determined negatively based on the target coverage level determined in step S3. For example, the higher the target coverage level, the lower the conflict level is determined. In step S404, based on the conflict level determined in step S403, two candidate physical layer parameters with the same or closest conflict level are found as the physical layer parameter combination to be obtained in step S4. Thus, when executing steps S5-S6, a coverage enhancement strategy can be generated and executed based on this physical layer parameter combination.

[0112] In this embodiment, the principle of executing steps S401-S404 is as follows: by executing steps S401-S404, the physical layer parameter combination can be dynamically determined according to factors such as the current service type and the amount of real-time resources. This achieves a different method of obtaining physical layer parameter combinations than the fixed physical layer parameter combinations in Table 3, enabling dynamic adjustment of the coverage enhancement strategy. This is beneficial for finding the physical layer parameter combination with the least conflict to determine the coverage enhancement strategy.

[0113] After executing step S4, which determines the combination of physical layer parameters to be used in a fixed or dynamic manner, the PCF strategy layer executes step S5 to generate a coverage enhancement strategy based on the combination of physical layer parameters.

[0114] Specifically, the PCF policy layer can encapsulate the physical layer parameters determined in step S4 into a policy package CoveragePolicyIE. A new CoveragePolicyEnhancementIE is added to the NGAP protocol, which contains the policy package CoveragePolicyIE, to implement the N2 interface enhancement design.

[0115] The PCF policy layer sends the policy packet CoveragePolicyIE to the AMF, which then executes step S6.

[0116] In this embodiment, when AMF executes step S6, which is the step of executing the coverage enhancement strategy, it can specifically perform the following steps:

[0117] S601. Obtain capability indication information reported by the user terminal;

[0118] S602. If the capability indication information meets the judgment conditions, the coverage enhancement strategy is sent to the first base station;

[0119] S603. Obtain the base station configuration information returned by the first base station;

[0120] S604. Send the base station configuration information to the second base station and forward it to the user terminal;

[0121] S605. Trigger the user terminal to perform pre-adjustment based on the base station configuration information;

[0122] S606. Switch the communication connection of the user terminal from the second base station to the first base station.

[0123] The process of steps S601-S606 is as follows: Figure 3 and Figure 4 As shown.

[0124] Reference Figure 3 In step S601, the user terminal UE can report the capability indication information CoverageCapability in the Msg3 PUSCH via LCID. Specifically, the user terminal UE can send Msg3 PUSCH to gNB2 (the second base station) when it detects a triggering condition (e.g., detecting that the current RSRP < -120dBm or receiving the coverageEnhancementRequest flag in SIB1).

[0125] The CoverageCapability indicator indicates the set of capabilities, representing the user terminal's support capabilities for coverage enhancement strategies. For example, the contents of LCID are shown in Table 4.

[0126] Table 4

[0127] LCID meaning Bit mapping 0x34 Supports SSB=160ms bit0:1 = Support 0x35 Support Msg4 repetition bit1-2: Maximum number of repetitions

[0128] Reference Figure 3 In step S602, the AMF determines whether a coverage enhancement strategy is supported based on the CoverageCapability information. If the determination condition is met, such as the user terminal UE supporting the coverage enhancement strategy, then... Figure 3 After the AMF updates the information in the UDM, it will send the CoveragePolicy obtained in step S5 to gNB2 (the second base station). (Refer to...) Figure 4 The AMF can send the CoveragePolicy to gNB1 (the first base station).

[0129] Reference Figure 4 After receiving the CoveragePolicy sent by AMF, gNB1 (the first base station) and gNB2 (the second base station) parse and execute the CoveragePolicy, for example:

[0130] ① If the CoveragePolicy includes "Configure SSB Period", gNB1 (the first base station) can directly modify the cell-level parameter ssb-PeriodicityServingCe11 to configure the SSB period to a specific value according to the CoveragePolicy.

[0131] ② If the CoveragePolicy includes "Activate PDCCH Repetition" (i.e., pdcchRepetition = true), gNB1 (the first base station) can write a specific value into the reserved bit of PBCH (Physical Broadcast Channel). This value must satisfy the formula a_bar(A) + 7 = 1 (i.e., a_bar(A) = -6), thereby activating the physical layer coverage enhancement process of "PDCCH Repetition".

[0132] ③ If the CoveragePolicy includes "trigger SIB1 repeated linkage" (i.e., sib1Linkage = linked), gNB1 (the first base station) can trigger the joint repeated transmission of Type0-PDCCH and SIB1, thereby triggering the physical layer coverage enhancement process of "SIB1 repeated linkage".

[0133] In this embodiment, refer to Figure 4 After parsing and executing the coverage enhancement policy CoveragePolicy, gNB1 (the first base station) can also generate base station configuration information TargetNTNConfig, execute step S603, and send the base station configuration information TargetNTNConfig to AMF.

[0134] Reference Figure 4 The AMF can execute step S604, sending the base station configuration information TargetNTNConfig to the user terminal UE through gNB2 (the second base station), so that the user terminal UE can pre-configure according to the base station configuration information TargetNTNConfig sent by gNB1 (the first base station) before switching the communication connection to gNB1 (the first base station).

[0135] Specifically, in step S605, the user terminal UE performs the following pre-adjustments based on the received base station configuration information TargetNTNConfig before handover:

[0136] If the target cell SSB period is 160ms, start extended period search in advance;

[0137] Reserve a HARQ soft buffer based on msg4RepFactor.

[0138] After the user terminal (UE) is pre-configured, the AMF can execute step S606. (Refer to...) Figure 4 The AMF can send a handover request to gNB1 (the first base station) and carry the coverage policy in the handover request. After receiving the handover ACK information returned by gNB1 (the first base station), the AMF can send a handover command to gNB2 (the second base station), so that the user terminal UE establishes a communication connection with gNB1 (the first base station) according to the coverage policy, and the user terminal UE disconnects from gNB2 (the second base station), thereby switching the user terminal's communication connection from gNB2 (the second base station) to gNB1 (the first base station).

[0139] In this embodiment, the Handover Command sent by AMF to gNB2 (the second base station) can embed the target cell SSB period and Msg4 configuration, thereby enhancing the handover command.

[0140] In this embodiment, by executing steps S601-S606, the coverage enhancement strategy can be used to optimize the process of the user terminal UE switching from gNB2 (second base station) to gNB1 (first base station), thereby reducing resource conflicts during the base station handover process.

[0141] In this embodiment, by executing steps S1-S6, the core network of the non-terrestrial network, through global coordination, defines the target coverage level based on factors such as service requirements represented by the service type and the relative position information between the user terminal and the base station. It then generates a combination of physical layer parameters to be used in the coverage enhancement strategy based on the target coverage level. This combination of physical layer parameters may include one or more physical layer parameters such as SSB, PDCCH, SIB1, and Msg4, thereby realizing a cross-layer dynamic coordination coverage enhancement strategy using multiple physical layer parameters. This helps reduce resource conflicts caused by the independent implementation of multiple single physical layer parameter coverage enhancement strategies, and alleviates the difficulty of simultaneously meeting different needs with limited wireless resources (such as the needs of resource-intensive applications like "long-cycle identity broadcasting" and "high-frequency command repetition"). This enhances communication stability in non-terrestrial network scenarios. Specifically, it also includes the following technical effects:

[0142] Cross-layer cooperative gain: To address the high latency and resource constraints of satellite-to-ground links, a dynamic resource scheduling algorithm with a long-period SSB (160ms) and high-frequency PDCCH repetition is implemented. Through a time-slot-level symbol resource reuse mechanism, the PDCCH repetition density is increased while ensuring synchronization signal coverage, thereby improving spectral efficiency. This invention overcomes the satellite beam switching latency limitation and maximizes air interface resource utilization.

[0143] Service awareness capabilities: Build a CoverageClass adaptive engine based on QoS levels. For eMBB services, improve the reliability of high-volume transmission; for uRLLC services, enable emergency repeat mode to ensure reduced end-to-end latency of critical commands.

[0144] Seamless handover assurance: An inter-satellite coverage parameter pre-synchronization protocol is designed, which transmits the terminal's historical CoverageClass configuration, SSB periodicity preference, and PDCCH repetition factor to the target satellite before handover via AMF. Combined with ephemeris prediction algorithms, beam pointing compensation values ​​are generated to reduce satellite handover interruption time, ensure service continuity for highly mobile terminals (aviation / maritime), and improve handover success rate.

[0145] The following is a case study of an emergency call from a maritime terminal to illustrate steps S1-S6. In this case:

[0146] Execute step S1 to determine the service type as uRLLC, with a corresponding service priority index P = 5;

[0147] Execute step S2 to determine the altitude of the LEO orbit as h = 1200km, the coordinates of the nadir point as (22.3°N, 113.5°E), and the latitude and longitude of the user terminal UE as (22.2°N, 113.6°E), thereby calculating the elevation angle θ = 28°;

[0148] Execute step S3 to calculate the target coverage level as: CoverageClass = 0.4 × 5 + 0.3 × (1 - 5 / 28) + 0.3 × (1 - 1200 / 2000) = 4.2, thus determining the target coverage level as "High Level".

[0149] Execute step S4 to determine that the combination of physical layer parameters used in the coverage enhancement strategy is "trigger PDCCH repetition + Msg4 maximum repetition";

[0150] By executing steps S5 and S6, and applying the coverage enhancement strategy, the following effects can be achieved:

[0151] ①The PDCCH repetition factor R=4, which reduces the consumption of time-domain resources;

[0152] ② The Msg4 repetition count is 8, which increases the number of HARQ processes;

[0153] ③ End-to-end latency is reduced, thereby meeting the requirements of uRLLC service type.

[0154] A computer program for enhancing communication coverage for non-terrestrial networks as described in this embodiment can be written into a computer device or storage medium. When the computer program is read out and run, the method for enhancing communication coverage for non-terrestrial networks as described in this embodiment is executed, thereby achieving the same technical effect as the method for enhancing communication coverage for non-terrestrial networks in the embodiment.

[0155] It should be noted that, unless otherwise specified, when a feature is referred to as "fixed" or "connected" to another feature, it can be directly fixed or connected to the other feature, or indirectly fixed or connected to the other feature. Furthermore, the descriptions of "upper," "lower," "left," and "right" used in this disclosure are only relative to the relative positional relationships of the components of this disclosure in the accompanying drawings. The singular forms "a," "an," and "the" used in this disclosure are also intended to include the plural forms, unless the context clearly indicates otherwise. Moreover, unless otherwise defined, all technical and scientific terms used in this embodiment have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this embodiment specification is only for describing particular embodiments and is not intended to limit the invention. The term "and / or" as used in this embodiment includes any combination of one or more of the associated listed items.

[0156] It should be understood that although the terms first, second, third, etc., may be used to describe various elements in this disclosure, these elements should not be limited to these terms. These terms are only used to distinguish elements of the same type from each other. For example, a first element may also be referred to as a second element without departing from the scope of this disclosure, and similarly, a second element may also be referred to as a first element. The use of any and all instances or exemplary language (“e.g.,” “such as,” etc.) provided in this embodiment is intended only to better illustrate embodiments of the invention and, unless otherwise required, does not impose a limitation on the scope of the invention.

[0157] It should be recognized that embodiments of the present invention can be implemented or carried out by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer-readable storage medium. The method can be implemented using standard programming techniques—including a non-transitory computer-readable storage medium configured with a computer program, wherein such a storage medium causes the computer to operate in a specific and predefined manner—according to the methods and drawings described in the specific embodiments. Each program can be implemented in a high-level procedural or object-oriented programming language to communicate with the computer system. However, if desired, the program can be implemented in assembly or machine language. In any case, the language can be a compiled or interpreted language. Furthermore, for this purpose, the program can run on a programmed application-specific integrated circuit (ASIC).

[0158] Furthermore, the procedures described in this embodiment can be performed in any suitable order, unless otherwise indicated by this embodiment or otherwise obviously contradictory to the context. The procedures (or variations and / or combinations thereof) described in this embodiment can be executed under the control of one or more computer systems configured with executable instructions, and can be implemented by hardware or a combination thereof as code (e.g., executable instructions, one or more computer programs, or one or more applications) that commonly executes on one or more processors. A computer program includes multiple instructions executable by one or more processors.

[0159] Furthermore, the method can be implemented in any suitable type of computing platform, including but not limited to personal computers, minicomputers, mainframes, workstations, networked or distributed computing environments, standalone or integrated computer platforms, or in communication with charged particle tools or other imaging devices, etc. Aspects of the invention can be implemented as machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, optical read and / or write storage medium, RAM, ROM, etc., such that it is readable by a programmable computer, and when the storage medium or device is read by the computer, it can be used to configure and operate the computer to perform the processes described herein. Furthermore, the machine-readable code, or portions thereof, can be transmitted via wired or wireless networks. The invention of this embodiment includes these and other different types of non-transitory computer-readable storage media when such media comprises instructions or programs that implement the steps above in conjunction with a microprocessor or other data processor. When programmed according to the methods and techniques of the invention, the invention also includes the computer itself.

[0160] A computer program can be applied to input data to perform the functions of this embodiment, thereby transforming the input data to generate output data stored in non-volatile memory. The output information can also be applied to one or more output devices, such as a display. In a preferred embodiment of the invention, the transformed data represents physical and tangible objects, including specific visual depictions of physical and tangible objects generated on the display.

[0161] The above are merely preferred embodiments of the present invention. The present invention is not limited to the above-described embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention, as long as they achieve the technical effects of the present invention by the same means, should be included within the scope of protection of the present invention. Within the scope of protection of the present invention, the technical solutions and / or implementation methods can have various modifications and variations.

Claims

1. A method for enhancing communication coverage in non-terrestrial networks, characterized in that, The communication coverage enhancement method for non-terrestrial networks includes: To obtain the service types of communication services provided by non-terrestrial networks to user terminals; The relative position information between the first base station in the non-terrestrial network and the user terminal is obtained; the first base station is a base station that can establish a communication connection with the user terminal at a future time. The target coverage level is determined based on the service type and the relative location information; Based on the target coverage level, a combination of physical layer parameters is determined; the combination of physical layer parameters includes one or more physical layer parameters. Based on the combination of physical layer parameters, a coverage enhancement strategy is generated; Execute the coverage enhancement strategy; The step of obtaining the relative position information between the first base station in the non-terrestrial network and the user terminal includes: Obtain the ephemeris information of the first base station; Based on the ephemeris information, determine the sub-satellite point coordinates and altitude of the first base station at the future time; Predict the latitude and longitude of the user terminal at the future time; Based on the coordinates, altitude, and latitude and longitude of the satellite nadir point, determine the elevation angle and distance of the first base station relative to the user terminal at a future time; The elevation angle and the distance are used as the relative position information; Determining the target coverage level based on the service type and the relative location information includes: Obtain the business priority index corresponding to the business type; A first weight, a second weight, and a third weight are defined; the first weight corresponds to the business priority index, the second weight corresponds to the elevation angle, and the third weight corresponds to the distance. Based on the first weight, the second weight, and the third weight, the business priority index, the elevation angle, and the distance are weighted and summed. The target coverage level is determined based on the weighted summation result, in a positive correlation.

2. The communication coverage enhancement method for non-terrestrial networks according to claim 1, characterized in that, The step of determining the physical layer parameter combination based on the target coverage level includes: When the target coverage level is high, configure PDCCH repetition to be activated and Msg4 to be configured with the maximum number of repetitions to obtain the physical layer parameter combination. When the target coverage level is medium, configure the SSB cycle and configure the triggering of SIB1 repeated linkage to obtain the physical layer parameter combination; When the target coverage level is low, configure the SSB cycle to obtain the physical layer parameter combination.

3. The communication coverage enhancement method for non-terrestrial networks according to claim 1, characterized in that, The step of determining the physical layer parameter combination based on the target coverage level includes: Obtain parameters for multiple candidate physical layers; Obtain the conflict level between any two candidate physical layer parameters when performing the aforementioned service type; Based on the target coverage level, the conflict level is determined in a negative correlation; The combination of physical layer parameters is determined based on the two candidate physical layer parameters having the determined conflict level.

4. The communication coverage enhancement method for non-terrestrial networks according to claim 3, characterized in that, The acquisition of the conflict level between any two candidate physical layer parameters when performing the aforementioned service type includes: For any two candidate physical layer parameters, obtain the time-domain conflict index, frequency-domain conflict index, and power conflict index between the two candidate physical layer parameters when performing the service type. The conflict level is determined based on the time-domain conflict index, the frequency-domain conflict index, and the power conflict index.

5. The communication coverage enhancement method for non-terrestrial networks according to claim 4, characterized in that, Determining the conflict level based on the time-domain conflict index, the frequency-domain conflict index, and the power conflict index includes: Based on the first weight, set the weights corresponding to the time-domain conflict index and the frequency-domain conflict index; Based on the second weight and the third weight, the weight corresponding to the power conflict index is set; The time-domain conflict index, the frequency-domain conflict index, and the power conflict index are weighted and summed. The conflict level is determined based on the weighted summation result, in a positive correlation.

6. The communication coverage enhancement method for non-terrestrial networks according to any one of claims 1-5, characterized in that, The execution of the coverage enhancement strategy includes: Obtain capability indication information reported by the user terminal; the capability indication information indicates the user terminal's support capability for the coverage enhancement strategy. When the capability indication information meets the judgment conditions, the coverage enhancement strategy is sent to the first base station; Obtain the base station configuration information returned by the first base station; the base station configuration information is generated by the first base station in response to the coverage enhancement strategy; The base station configuration information is sent to the second base station and then forwarded to the user terminal; the second base station is the base station currently establishing a communication connection with the user terminal. The user terminal is triggered to perform a pre-adjustment based on the base station configuration information; The communication connection of the user terminal is switched from the second base station to the first base station.

7. A computer device, characterized in that, It includes a memory and a processor, the memory being used to store at least one program, and the processor being used to load at least one program to execute the communication coverage enhancement method for non-terrestrial networks as described in any one of claims 1-6.

8. A computer-readable storage medium storing a processor-executable program, characterized in that, The processor-executable program, when executed by the processor, is used to perform the communication coverage enhancement method for non-terrestrial networks as described in any one of claims 1-6.

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