Frame structure implementation method based on non-ground network

Abstract

The invention discloses a frame structure implementation method based on a non-terrestrial network, and belongs to the field of non-terrestrial network communication. The method comprises the following steps: an S-gNB broadcasts by using an initial TDD frame structure; after receiving the broadcast, the UE performs random access and reports TA information; the S-gNB divides the UE into different types according to the TA information or the measurement report uploaded by the UE; the measurement report is generated and obtained by the UE according to own measurement control information; the S-gNB determines a configuration scheme of a flexible time slot of the UE according to the type of the UE and the service request information, and issues indication information; and the UE dynamically adjusts the time slot according to the received indication information so as to realize communication between different frame structures and the S-gNB. According to the invention, the TDD frame structure of the UE is dynamically adjusted according to classification, a stable and coherent frame structure switching strategy and a dynamic scheduling strategy adapted to the service requirements of the user are provided, and the NTN is helped to realize efficient TDD frame structure management.

Description

Technical Field

[0001] The present invention relates to the field of non-terrestrial network communications, and in particular to a method for realizing a frame structure based on a non-terrestrial network. Background Art

[0002] The time division duplex (TDD) full-duplex mode has efficient frequency band utilization and dynamic and flexible time slot allocation. It can adapt to the needs of different scenarios and different services in communication, so it has been widely used in terrestrial networks. At present, 3GPP has defined the frequency division duplex (FDD) mode of FR1 in non-terrestrial networks (NTN), but there is no unified discussion result and standard for the TDD mode.

[0003] The terrestrial TDD wireless frame structure needs to have a protection interval that is greater than the round-trip delay. In non-terrestrial networks, the round-trip delay between the satellite and the terminal is significantly larger than that on the ground, and the protection interval of the TDD wireless frame structure accounts for a large proportion, which seriously squeezes the effective time for data transmission in each frame and has low resource utilization. Possible solutions include lengthening the period of the TDD frame structure and combining the original 10ms frame structure period to reduce the proportion of the protection interval, which can improve resource utilization to a certain extent, but the lengthening of the period will also increase the delay of uplink and downlink scheduling. In addition, the existing dynamic time slot adjustment solution has a complex process and lacks a stable and coherent NTN frame structure management strategy, which is relatively inefficient.

[0004] In summary, there is still a lack of efficient NTN TDD frame structure solutions and dynamic scheduling strategies that adapt to users' business needs to improve the air interface efficiency of TDD in scenarios with large round-trip delays such as satellites. It is also necessary to introduce a more stable and coherent TDD frame structure management strategy. Summary of the invention

[0005] In order to solve at least one of the technical problems existing in the prior art to a certain extent, the object of the present invention is to provide a method for realizing a frame structure based on a non-terrestrial network.

[0006] The first technical solution adopted by the present invention is:

[0007] A method for implementing a frame structure based on a non-terrestrial network comprises the following steps:

[0008] The S-gNB uses the initial TDD frame structure for broadcasting;

[0009] After receiving the broadcast, the UE performs random access and reports the TA information;

[0010] The S-gNB classifies the UE into different types according to the TA information or measurement report uploaded by the UE; the measurement report is generated by the UE according to its own measurement control information;

[0011] The S-gNB determines the configuration scheme of the UE flexible time slot according to the UE type and service request information, and issues the indication information;

[0012] The UE dynamically adjusts the time slot according to the received indication information to achieve different frame structures and communicate with the S-gNB.

[0013] Furthermore, the S-gNB classifies the UE into different types according to the TA information uploaded by the UE, including:

[0014] Classify the UE into near-point UE, mid-point UE or far-point UE according to the TA information;

[0015] Among them, UEs whose TA is less than or equal to the first preset time are classified as near-point UEs; UEs whose TA is greater than the first preset time and less than or equal to the second preset time are classified as mid-point UEs; UEs whose TA is greater than the second preset time and less than or equal to the third preset time are classified as far-point UEs; the first preset time < the second preset time < the third preset time.

[0016] It should be noted that in this embodiment, UE is divided into three types: near-point UE, mid-point UE or far-point UE, but the protection scope of the present invention is not limited to this case; for example, for satellites with higher orbits, UE can be divided into four or more categories, and the specific number of types can be divided according to specific circumstances; or for some low-orbit satellites, UE can be directly divided into two categories. In general, the protection scope of the present invention involves the division of UE, and the specific division method should fall within the protection scope of the present invention.

[0017] Furthermore, the measurement control information includes a distance threshold, and different types of UEs have different measurement control information:

[0018] For the far-point UE, the measurement control information includes a first distance threshold; when the far-point UE detects that the distance between the UE and the S-gNB is less than the first distance threshold, the far-point UE triggers uploading of a first measurement report, and after receiving the first measurement report, the S-gNB divides the far-point UE into a midpoint UE;

[0019] For the midpoint UE, the measurement control information includes a first distance threshold and a second distance threshold; when the midpoint UE detects that the distance between the UE and the S-gNB is greater than the first distance threshold, the midpoint UE triggers uploading a second measurement report, and after the S-gNB receives the second measurement report, it classifies the midpoint UE as a far-point UE; when the midpoint UE detects that the distance between the UE and the S-gNB is less than the second distance threshold, the midpoint UE triggers uploading a third measurement report, and after the S-gNB receives the third measurement report, it classifies the midpoint UE as a near-point UE;

[0020] For the near-point UE, the measurement control information includes a second distance threshold; when the near-point UE detects that the distance between the UE and the S-gNB is greater than the second distance threshold, the near-point UE triggers uploading of a fourth measurement report, and after receiving the fourth measurement report, the S-gNB divides the near-point UE into a midpoint UE;

[0021] Among them, the first distance threshold>the second distance threshold.

[0022] Furthermore, when calculating the distance between the UE and the S-gNB, the coordinates corresponding to the S-gNB are obtained through the ephemeris parameters broadcast by SIB19 or the referenceLocation in the D event.

[0023] Furthermore, the initial TDD frame structure includes a downlink time slot, a flexible time slot and an uplink time slot;

[0024] The S-gNB determines a configuration scheme of a UE flexible time slot according to the type of the UE and the service request information, including:

[0025] Allocate a callable flexible time slot to the UE according to the type of the UE;

[0026] If the UE's service request is mainly for downlink, all available flexible time slots are adjusted to downlink time slots; if the UE's service request is mainly for uplink, all available flexible time slots are adjusted to uplink time slots; if the UE's service request has requirements for both uplink and downlink, some of the available flexible time slots are adjusted to uplink time slots, and the other part is adjusted to downlink time slots.

[0027] Further, when the ratio of the number of downlink time slots, flexible time slots and uplink time slots is 2:6:2;

[0028] For the midpoint UE, the maximum number of flexible time slots that can be called is 1; if the service request is mainly for downlink, the first flexible time slot F in its frame structure is adjusted to the downlink time slot D; if the service request is mainly for uplink, the first flexible time slot F in its frame structure is adjusted to the uplink time slot U.

[0029] Further, when the ratio of the number of downlink time slots, flexible time slots and uplink time slots is 2:6:2;

[0030] For near-point UEs, the maximum number of flexible time slots that can be called is 3; if the service request is mainly based on downlink, the first three flexible time slots F in its frame structure are adjusted to downlink time slots D; if the service request is mainly based on uplink, the first three flexible time slots F in its frame structure are adjusted to uplink time slots U.

[0031] Further, when the ratio of the number of downlink time slots, flexible time slots and uplink time slots is 2:6:2;

[0032] For far-point UEs, there is no flexible time slot available, and the S-gNB uses the broadcast frame structure for scheduling without changing the frame structure.

[0033] It should be noted that the time slot ratio of the initial frame structure is not necessarily 2:6:2. Specifically, the number of flexible time slots depends on the maximum access round-trip delay, and the number of uplink and downlink time slots is not limited. In this embodiment, the maximum round-trip delay does not exceed 6ms, so the flexible time slot is 6, so in addition to the ratio of 2:6:2, 3:6:1, 1:6:3, etc. can also be taken. In other embodiments, if the maximum round-trip delay does not exceed 7ms, the flexible time slot value is 7. When the value of the flexible time slot is different, the maximum number of flexible time slots allocated to various similar UEs is also different, such as: the maximum number of flexible time slots allocated to the midpoint UE is not limited to 1, and the maximum number of flexible time slots allocated to the near-point UE is not limited to 3; in some embodiments, flexible time slots can also be allocated to the far-point UE. In summary, it can be seen that the protection scope of the present invention is not limited to the three timeslot ratios of 2:6:2, but also includes other ratios, so other situations should also fall within the protection scope of the present invention.

[0034] The second technical solution adopted by the present invention is:

[0035] A frame structure implementation method based on a non-terrestrial network, applied to an S-gNB, comprises the following steps:

[0036] Use the initial TDD frame structure for broadcasting, so that after receiving the broadcast, the UE performs random access and reports the TA information;

[0037] The UE is classified into different types according to the TA information or measurement report uploaded by the UE; the measurement report is generated by the UE according to its own measurement control information;

[0038] According to the type of UE and service request information, the configuration scheme of the UE flexible time slot is determined, and indication information is issued so that the UE dynamically adjusts the time slot according to the received indication information.

[0039] The third technical solution adopted by the present invention is:

[0040] A method for implementing a frame structure based on a non-terrestrial network, applied to a UE, comprises the following steps:

[0041] After receiving the broadcast signal sent by the S-gNB using the initial TDD frame structure, perform random access and report the TA information, so that the S-gNB allocates the corresponding measurement control information according to the TA information or measurement report uploaded by the UE, and determines the configuration scheme of the UE flexible time slot according to the UE type and service request information, and sends the indication information; the measurement report is generated by the UE according to its own measurement control information;

[0042] After receiving the indication information, the time slot is dynamically adjusted according to the indication information to realize communication with different frame structures.

[0043] The beneficial effects of the present invention are as follows: the present invention classifies UEs according to the TA initially reported by the UE and the type of D event triggered by the UE by introducing a new TDD frame structure management strategy. For UEs of the same type, the sending of their D events and the frame structure switching process can be uniformly managed, which is conducive to achieving smooth and coherent frame structure adjustments. S-gNB can achieve more convenient UE dynamic time slot control and flexibly adjust the uplink and downlink frame structures according to the type of UE and service requirements, and can better meet the different service requirements of different UEs. In addition, compared with the period extension scheme of the conventional NR TDD wireless frame structure and TDD frame structure, it more effectively improves the time slot utilization and does not increase the delay of uplink and downlink scheduling. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the embodiments of the present invention or the drawings of related technical solutions in the prior art are introduced below. It should be understood that the drawings introduced below are only for the convenience of clearly describing some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0045] Figure 1 is a schematic diagram of a TDD frame structure scenario based on a non-terrestrial network in an embodiment of the present invention;

[0046] Figure 2 It is a flowchart of a method for implementing a frame structure based on a non-terrestrial network in an embodiment of the present invention;

[0047] Figure 3 1 is a schematic diagram of data interaction between an S-gNB and a UE in an embodiment of the present invention;

[0048] Figure 4 is a schematic diagram of classification of UEs by the S-gNB in ​​an embodiment of the present invention;

[0049] Figure 5 is a schematic diagram of a midpoint UE flexibly and dynamically adjusting a downlink time slot in an embodiment of the present invention;

[0050] Figure 6 is a schematic diagram of a near-point UE flexibly and dynamically adjusting a downlink time slot in an embodiment of the present invention;

[0051] Figure 7 is a schematic diagram of a midpoint UE flexibly and dynamically adjusting an uplink time slot in an embodiment of the present invention;

[0052] Figure 8 is a schematic diagram of a near-point UE flexibly and dynamically adjusting an uplink time slot in an embodiment of the present invention;

[0053] Fig. 9 It is a schematic diagram of codes for D3 event and D4 event in an embodiment of the present invention. DETAILED DESCRIPTION

[0054] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and are not to be construed as limitations of the present invention. For the step numbers in the following embodiments, they are only provided for the convenience of explanation, and the order between the steps is not limited in any way, and the execution order of each step in the embodiment can be adaptively adjusted according to the understanding of those skilled in the art.

[0055] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0056] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0057] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0058] Terminology explanation:

[0059] S-gNB: Satellite-gNodeB, satellite base station.

[0060] UE: User Equipment, user terminal.

[0061] TA: time advance, time advance.

[0062] NTN: non-terrestrial network.

[0063] TDD: time division duplex.

[0064] In view of the existing technical problems, the present invention aims to introduce the TDD full-duplex mode into NTN. In view of the problems of short effective transmission time and low resource utilization caused by large round-trip delay in NTN scenario, a TDD frame structure implementation scheme based on NTN is proposed. While meeting the needs of ground users and improving resource utilization, the TDD frame structure of UE is dynamically adjusted by classification, and a smooth and coherent frame structure switching strategy and a dynamic scheduling strategy adapted to the business needs of users are provided, which helps NTN to achieve efficient TDD frame structure management.

[0065] An embodiment of the present invention provides a method for implementing a frame structure based on NTN, comprising the following steps:

[0066] Step 1: The S-gNB uses the initial frame structure for broadcasting, the UE performs random access, and reports the initial TA.

[0067] Step 2: The S-gNB classifies the UE into near-point, mid-point, or far-point types based on the TA information initially reported by the UE or the type of D3 or D4 event triggered.

[0068] Step 3: S-gNB prepares different D event measurement control information for different types of UEs. For far-point UEs, the message carries D3 event measurement control information; for midpoint UEs, the message carries both D3 and D4 event measurement control information. For near-point UEs, the message carries D3 event measurement control information.

[0069] Step 4: The S-gNB determines the configuration scheme of the UE's flexible time slot according to the UE type and service request information, and indicates the UE's dynamic time slot adjustment result through DCI format 2_0 or tdd-UL-DL-ConfigDedicated.

[0070] Step 5: Due to the change in location, after the UE triggers the D3 event or the D4 event, it reports the measurement information and returns to execute step 2.

[0071] In some embodiments, the TDD frame structure in the NTN scenario includes downlink time slots, flexible time slots and uplink time slots. The flexible time slots can be configured at the cell level by the RRC parameter TDD-UL-DL-ConfigCommon. It can also be configured at the UE level by TDD-UL-DL-ConfigDedicated. At the same time, the downlink control information DCI can also configure the use of flexible time slots.

[0072] As an optional implementation, the S-gNB divides the UE into three categories according to the timing advance (TA) of the user access, namely, near-point UE, mid-point UE, and far-point UE. It should be noted that this embodiment divides the UE into three categories, but the technical solution of dividing into multiple categories (two or more than three categories) also belongs to the protection scope of the present invention.

[0073] In some embodiments, due to the change in the relative distance between the UE and the S-gNB (Satellite-gNodeB), the UE classification needs to be dynamically adjusted. The UE triggers measurement reporting through the D event, and the S-gNB reclassifies the UE according to the type of event triggered and the current UE classification. To support D event triggering UE type update, new D3 and D4 events are added. Fig. 9 , specifically defined as follows:

[0074] The triggering condition of the D3 event is: the distance between the UE location and referenceLocation-D3 is less than or equal to the threshold distanceThreshFromReference-D3;

[0075] The exit condition of the D3 event is: the distance between the UE location and referenceLocation-D3 is greater than the threshold distanceThreshFromReference-D3;

[0076] The triggering condition of the D4 event is: the distance between the UE location and referenceLocation-D4 is less than or equal to the threshold distanceThreshFromReference-D4;

[0077] The exit condition of the D4 event is: the distance between the UE location and referenceLocation-D4 is greater than the threshold distanceThreshFromReference-D4.

[0078] The above contents are explained in detail below with reference to the accompanying drawings.

[0079] See also Figure 1 : It is a schematic diagram of the applicable scenario of the present invention;

[0080] The present invention is applicable to NTN transparent load architecture and renewable load architecture. S-gNB broadcasts with a fixed TDD frame structure. After receiving the broadcast, multiple UEs distributed on the ground perform random access and report TA information. S-gNB will classify ground UEs into different types according to the TA information of the UE, such as near-point UE, mid-point UE and far-point UE (for satellites with higher orbits, it can be divided into more types). When providing services, S-gNB uniformly plans and dynamically adjusts the frame structure of various types of UEs, so that different types of UEs will use different TDD frame structures and the same type of UEs will use the same TDD frame structure.

[0081] The overall implementation process is as follows Figure 2 , S-gNB uses the initial TDD frame structure for broadcasting, UE performs random access, and reports the initial TA. At the time of initial access, S-gNB will classify UEs according to the TA information reported by UE, including near-point UE, mid-point UE, and far-point UE. For different UE types, different D events will be sent through RRC Reconfiguration messages. At the same time, different types of UEs will also communicate with S-gNB through dynamic time slot adjustment to achieve different frame structures. After the relative position of UE and S-gNB changes, UE triggers D event measurement reporting. S-gNB will reclassify the UE type according to the D event type reported by UE, forming a complete frame structure switching process.

[0082] The signaling process involved in the above process is as follows Figure 3:The UE first needs to complete the initial access. During the initial access, the timing advance information TA will be reported, which is the basis for the S-gNB to initially classify the UE. After the S-gNB completes the UE classification, it will send different RRC Reconfiguration messages to different types of UEs, which carry the measurement control information of the D3 or D4 event and the relevant configuration information of tdd-UL-DL-ConfigDedicated or DCI format 2_0 for flexible time slot adjustment. After successful reception, the UE will inform the S-gNB through the RRC Reconfiguration complete message. After that, different types of UEs will use the adjusted frame structure for services. Due to the change in the relative position of the UE and the S-gNB, the UE triggers the D event and reports the Measurement report carrying the event name eventID. The S-gNB will reclassify the UE according to the eventID of the triggering event. A new RRC Reconfiguration message is sent to the UE, which carries the measurement control information of the D3 or D4 event different from the previous one and the relevant configuration information of tdd-UL-DL-ConfigDedicated or DCI format 2_0 for flexible time slot adjustment. After the S-gNB receives the RRC Reconfiguration Complete message, it is deemed that the adjustment of the new frame structure is completed.

[0083] The overall detailed embodiment is as follows:

[0084] (1) Taking the low-orbit LEO satellite communication scenario with a maximum access round-trip delay of less than 6 ms and a subcarrier spacing of 15 kHz as an example, the S-gNB uses the initial TDD frame structure for broadcasting, in which the number of downlink time slots, flexible time slots, and uplink time slots is in the ratio of 2:6:2; the UE performs random access and reports the initial TA.

[0085] (2) The S-gNB will classify the UE according to the TA information reported by the UE (initial access) or the D event type reported by the measurement.

[0086] The UE classification process is as follows: Figure 4 : During initial access, the S-gNB will classify the UE according to the TA information reported by the UE. Specifically, UEs with a TA less than or equal to 1ms are classified as near-point UEs; UEs with a TA greater than 1ms and less than or equal to 2ms are classified as mid-point UEs; UEs with a TA greater than 2ms and less than or equal to 3ms are classified as far-point UEs;

[0087] If a measurement report triggered by a D3 or D4 event is obtained, the S-gNB will classify the UE according to the type to which the UE currently belongs and the measID of the Measurement Report. Specifically, the conversion of UE types is as follows: Figure 4 As shown, when the far-point UE triggers the D3 event measurement and reporting, that is, the measID is eventD3, the S-gNB classifies the UE as a midpoint UE; when the midpoint UE triggers the D3 event measurement and reporting, that is, the measID is eventD3, the S-gNB classifies the UE as a near-point UE; when the midpoint UE triggers the D4 event measurement and reporting, that is, the measID is eventD4, the S-gNB classifies the UE as a far-point UE; when the near-point UE triggers the D4 event measurement and reporting, that is, the measID is eventD4, the S-gNB classifies the UE as a midpoint UE.

[0088] (3) For different types of UEs, the S-gNB prepares different measurement control information of D events for different types of UEs.

[0089] The reference positions of the D3 and D4 events are the current coordinates of the S-gNB, which can be obtained through the referenceLocation in the D event or through the ephemeris parameter SIB19-r17->ntn-Config-r17->ephemerisInfo-r17 broadcast by SIB19. The distance threshold is set to the distance threshold corresponding to the TA threshold value that distinguishes it from other UEs. The corresponding conversion formula is distanceThreshFromReference=TA thresh *c*10 -3 , where c is the speed of light in m / s, TA thresh It is the TA threshold value, in ms.

[0090] Specifically, for the far-point UE, the message carries the D3 event measurement control information, including eventD3>distanceThreshFromReference-D3 corresponding to the distance threshold set to:

[0091] distanceThreshFromReference=2*c*10 -3 (m)

[0092] For the midpoint UE, the message carries both D3 and D4 event measurement control information. The distance threshold corresponding to eventD3->distanceThreshFromReference-D3 is set to:

[0093] distanceThreshFromReference=1*c*10 -3(m)

[0094] eventD4->distanceThreshFromReference-D4 corresponding distance threshold is set to:

[0095] distanceThreshFromReference=2*c*10 -3 (m)

[0096] For the near-point UE, the message carries the D4 event measurement control information, where the distance threshold corresponding to eventD4->distanceThreshFromReference-D4 is set to:

[0097] distanceThreshFromReference=1*c*10 -3 (m)

[0098] (4) The S-gNB determines the configuration scheme of the UE's flexible time slot according to the UE type and service request information, and indicates the UE's dynamic time slot adjustment result through DCIformat 2_0 or tdd-UL-DL-ConfigDedicated.

[0099] If the UE's service request is mainly for downlink, all available flexible time slots are adjusted to downlink time slots. If the UE's service request is mainly for uplink, all available flexible time slots are adjusted to uplink time slots. If the UE's service request requires both uplink and downlink, some available flexible time slots are adjusted to uplink time slots and the other part are adjusted to downlink time slots.

[0100] For the specific scheduling process, for far-point UEs, since there is no callable flexible time slot, the S-gNB uses the broadcast frame structure for scheduling without changing the frame structure.

[0101] See also Figure 5, for the midpoint UE, the maximum number of flexible time slots that can be called is 1. If the service request is mainly the following behavior, the first flexible time slot in its frame structure can be adjusted to a downlink time slot. Specifically, in the RRC Reconfiguration message, the time slot format of time slot 3 is set to 0 on PDCCH-ServingCellConfig->slotFormatIndicator->slotFormatCombToAddModList->slotFormatCombinations->slotFormats, and the available slotFormatIndicator->sfi-RNTI and slotFormatIndicator->dci-PayloadSize are configured for the UE; or tdd-UL-DL-ConfigDedicated->slotSpecificConfigurationsToAddModList->TDD-UL-DL-SlotConfig->-slotIndex is set to 3, and TDD-UL-DL-SlotConfig->symbols is set to allDownlink, indicating that the UE has completed the time slot configuration.

[0102] See also Figure 6 , for near-point UEs, the maximum number of flexible time slots that can be called is 3. If the service request is mainly the following, the first three flexible time slots F can be adjusted to downlink time slots D in its frame structure. Specifically, in the RRC Reconfiguration message, the slot formats of time slots 3, 4, and 5 are set to 0 on PDCCH-ServingCellConfig->slotFormatIndicator->slotFormatCombToAddModList->slotFormatCombinations->slotFormats, and the available slotFormatIndicator->sfi-RNTI and slotFormatIndicator->dci-PayloadSize are configured for the UE; or tdd-UL-DL-ConfigDedicated->slotSpecificConfigurationsToAddModList->TDD-UL-DL-SlotConfig->slotIndex is set to 3, 4, and 5 respectively, and TDD-UL-DL-SlotConfig->symbols are all set to allDownlink, indicating that the UE has completed the time slot configuration.

[0103] See also Figure 7, for the midpoint UE, the maximum number of flexible time slots that can be called is 1. If the service request is mainly uplink, the first flexible time slot F in its frame structure can be adjusted to the uplink time slot U. Specifically, in the RRC Reconfiguration message, the time slot format of time slot 7 is set to 1 on PDCCH-ServingCellConfig->slotFormatIndicator->slotFormatCombToAddModList->slotFormatCombinations->slotFormats, and the available slotFormatIndicator->sfi-RNTI and slotFormatIndicator->dci-PayloadSize are configured for the UE; or tdd-UL-DL-ConfigDedicated->slotSpecificConfigurationsToAddModList->TDD-UL-DL-SlotConfig->slotIndex is set to 7, and TDD-UL-DL-SlotConfig->symbols is set to allUplink, indicating that the UE has completed the time slot configuration.

[0104] See also Figure 8 For near-point UEs, the maximum number of flexible time slots that can be called is 3. If the service request is mainly uplink, the first three flexible time slots F in its frame structure can be adjusted to uplink time slots U. Specifically, in the RRC Reconfiguration message, the slot formats of time slots 5, 6, and 7 are set to 1 on PDCCH-ServingCellConfig->slotFormatIndicator->slotFormatCombToAddModList->slotFormatCombinations->slotFormats, and the available slotFormatIndicator->sfi-RNTI and slotFormatIndicator->dci-PayloadSize are configured for the UE; or in the RRC high-level configuration tdd-UL-DL-ConfigDedicated->slotSpecificConfigurationsToAddModList, TDD-UL-DL-SlotConfig->slotIndex is set to 5, 6, and 7 respectively, and TDD-UL-DL-SlotConfig->symbols are all set to allUplink, indicating that the UE has completed the time slot configuration.

[0105] (5) Due to the change in the relative position of the UE and S-gNB, the UE triggers the D event and reports a Measurement report carrying the event name eventID.

[0106] Specifically, when the distance between the far-point UE and the S-gNB coordinates obtained by the configured event-D3->referenceLocation-D3 or the ephemeris parameter SIB19-r17->ntn-Config-r17->ephemerisInfo-r17 broadcasted by SIB19 is less than or equal to the threshold distanceThreshFromReference-D3, the D3 event is triggered. The UE reports the Measurement report with the event name eventID configured as eventD3.

[0107] When the distance between the midpoint UE and the configured event-D3->referenceLocation-D3 or the S-gNB coordinates obtained through the ephemeris parameter SIB19-r17->ntn-Config-r17->ephemerisInfo-r17 broadcasted by SIB19 is less than or equal to the threshold distanceThreshFromReference-D3, the D3 event is triggered. The UE reports the Measurement report with the event name eventID configured as eventD3.

[0108] When the distance between the midpoint UE and the S-gNB coordinates obtained by the configured event-D3->referenceLocation-D4 or the ephemeris parameter SIB19-r17->ntn-Config-r17->ephemerisInfo-r17 broadcasted by SIB19 is greater than the threshold distanceThreshFromReference-D4, the D4 event is triggered. The UE reports the Measurement report with the event name eventID configured as eventD4.

[0109] When the distance between the near UE and the S-gNB coordinates obtained by the configured event-D3->referenceLocation-D4 or the ephemeris parameter SIB19-r17->ntn-Config-r17->ephemerisInfo-r17 broadcasted by SIB19 is greater than the threshold distanceThreshFromReference-D4, the D4 event is triggered. The UE reports the Measurement report with the event name eventID configured as eventD4.

[0110] The UE process that completes the reporting will jump to step (2), and the S-gNB will reclassify the UE.

[0111] In summary, compared with the prior art, the present invention has the following advantages and beneficial effects: compared with the period lengthening scheme of the conventional NR TDD wireless frame structure and the TDD frame structure, it more effectively improves the time slot utilization rate and does not increase the delay of the uplink and downlink scheduling; secondly, by introducing a new TDD frame structure management strategy, the UE is classified according to the TA initially reported by the UE and the type of D event triggered. For UEs of the same type, the sending of their D events and the frame structure switching process can be uniformly managed, which is conducive to achieving smooth and coherent frame structure adjustment. S-gNB can achieve more convenient UE dynamic time slot control and flexibly adjust the uplink and downlink frame structures according to the type of UE and service requirements, which can better meet the different service requirements of different UEs.

[0112] In the above description of this specification, the description with reference to the terms "one embodiment / example", "another embodiment / example" or "certain embodiments / examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0113] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

[0114] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the above embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A method for implementing a frame structure based on a non-terrestrial network, characterized in that: The following steps are involved: The S-gNB uses the initial TDD frame structure for broadcasting; After receiving the broadcast, the UE performs random access and reports the TA information; The S-gNB classifies UEs into different types based on the TA information or measurement reports uploaded by the UEs. The measurement report is generated by the UE according to its own measurement control information; The S-gNB determines the configuration scheme of the UE flexible time slot according to the UE type and service request information, and issues the indication information; The UE dynamically adjusts the time slot according to the received indication information to achieve different frame structures and communicate with the S-gNB.

2. The method for implementing a frame structure based on a non-terrestrial network according to claim 1, characterized in that: The S-gNB According to the TA information uploaded by the UE, the UE is divided into different types, including: Classify the UE into near-point UE, mid-point UE or far-point UE according to the TA information; Among them, UEs whose TA is less than or equal to the first preset time are classified as near-point UEs; UEs whose TA is greater than the first preset time and less than or equal to the second preset time are classified as mid-point UEs; UEs whose TA is greater than the second preset time and less than or equal to the third preset time are classified as far-point UEs; the first preset time < the second preset time < the third preset time.

3. A method for implementing a frame structure based on a non-terrestrial network according to claim 2, characterized in that: The measurement control information includes a distance threshold, and different types of UEs have different measurement control information: For the far-point UE, the measurement control information includes a first distance threshold; when the far-point UE detects that the distance between the UE and the S-gNB is less than the first distance threshold, the far-point UE triggers uploading of a first measurement report, and after receiving the first measurement report, the S-gNB divides the far-point UE into a midpoint UE; For the midpoint UE, the measurement control information includes a first distance threshold and a second distance threshold; When the midpoint UE detects that the distance between the UE and the S-gNB is greater than the first distance threshold, the midpoint UE triggers uploading a second measurement report. After receiving the second measurement report, the S-gNB classifies the midpoint UE as a far-point UE. When the midpoint UE detects that the distance between the UE and the S-gNB is less than the second distance threshold, the midpoint UE triggers uploading a third measurement report. After receiving the third measurement report, the S-gNB classifies the midpoint UE as a near-point UE. For the near-point UE, the measurement control information includes a second distance threshold; when the near-point UE detects that the distance between the UE and the S-gNB is greater than the second distance threshold, the near-point UE triggers uploading of a fourth measurement report, and after receiving the fourth measurement report, the S-gNB divides the near-point UE into a midpoint UE; Among them, the first distance threshold>the second distance threshold.

4. The method for realizing a frame structure based on a non-terrestrial network according to claim 3, characterized in that: When calculating the distance between the UE and the S-gNB, the coordinates of the S-gNB are obtained through the ephemeris parameters broadcast by SIB19 or the referenceLocation in the D event.

5. The method for implementing a frame structure based on a non-terrestrial network according to claim 1, characterized in that: The initial TDD frame structure includes a downlink time slot, a flexible time slot and an uplink time slot; The S-gNB determines a configuration scheme of a UE flexible time slot according to the type of the UE and the service request information, including: Allocate a callable flexible time slot to the UE according to the type of the UE; If the UE's service request is mainly for downlink, all available flexible time slots are adjusted to downlink time slots; if the UE's service request is mainly for uplink, all available flexible time slots are adjusted to uplink time slots; if the UE's service request has requirements for both uplink and downlink, some of the available flexible time slots are adjusted to uplink time slots, and the other part is adjusted to downlink time slots.

6. A method for implementing a frame structure based on a non-terrestrial network according to claim 5, characterized in that: When the ratio of the number of downlink timeslots, flexible timeslots and uplink timeslots is 2:6:2; For the midpoint UE, the maximum number of flexible time slots that can be called is 1; if the service request is mainly for downlink, the first flexible time slot F in its frame structure is adjusted to the downlink time slot D; if the service request is mainly for uplink, the first flexible time slot F in its frame structure is adjusted to the uplink time slot U.

7. The method for realizing a frame structure based on a non-terrestrial network according to claim 5, characterized in that: When the ratio of the number of downlink timeslots, flexible timeslots and uplink timeslots is 2:6:2; For near-point UEs, the maximum number of flexible time slots that can be called is 3; if the service request is mainly based on downlink, the first three flexible time slots F in its frame structure are adjusted to downlink time slots D; if the service request is mainly based on uplink, the first three flexible time slots F in its frame structure are adjusted to uplink time slots U.

8. The method for implementing a frame structure based on a non-terrestrial network according to claim 5, characterized in that: When the ratio of the number of downlink timeslots, flexible timeslots and uplink timeslots is 2:6:2; For far-point UEs, there is no flexible time slot available, and the S-gNB uses the broadcast frame structure for scheduling without changing the frame structure.

9. A method for implementing a frame structure based on a non-terrestrial network, characterized in that: Applied to S-gNB, including the following steps: The initial TDD frame structure is used for broadcasting, so that after receiving the broadcast, the UE performs random access and reports TA information; the UE is divided into different types according to the TA information or measurement report uploaded by the UE; the measurement report is generated by the UE according to its own measurement control information; According to the type of UE and service request information, the configuration scheme of the UE flexible time slot is determined, and indication information is issued so that the UE dynamically adjusts the time slot according to the received indication information.

10. A method for implementing a frame structure based on a non-terrestrial network, characterized in that: Applied to UE, including the following steps: After receiving the broadcast signal sent by the S-gNB using the initial TDD frame structure, perform random access and report the TA information, so that the S-gNB allocates the corresponding measurement control information according to the TA information or measurement report uploaded by the UE, and determines the configuration scheme of the UE flexible time slot according to the UE type and service request information, and sends the indication information; the measurement report is generated by the UE according to its own measurement control information; After receiving the indication information, the time slot is dynamically adjusted according to the indication information to realize communication with different frame structures.

Images