Methods, apparatus and systems for data transmission, as well as terminals and network devices.

Abstract

In an embodiment of the present disclosure, a data transmission method, apparatus, and system, as well as a terminal and a network device, are provided. The solution includes receiving a paging message issued by a target network device according to a first time period when the current state of the target terminal is an inactive state; and, when the received paging message includes a designated paging record for the target terminal, sending a connection resumption request to the target network device, so as to send a downlink small data packet to the target terminal based on the received connection resumption request, where the designated paging record includes a downlink small data transmission in an inactive state indication, and the connection resumption reason in the connection resumption request is a downlink small data transmission in an inactive state. The technical solution of the embodiment of the present disclosure enables downlink data transmission of a terminal in an inactive state, reducing signaling overhead and time delay consumption in the data transmission process.

Description

Technical Field

[0005]

[0001] Cross - reference to related applications This disclosure is based on Chinese Patent Application No. 202210986742.0 filed on August 17, 2022, and claims the priority thereof. The disclosure of the application is incorporated herein by reference in its entirety.

[0002] This disclosure relates to the field of wireless communication technology, and more particularly, to a method, apparatus, and system for data transmission, as well as a terminal and a network device.

Background Art

[0003] In related technologies, in order for a user equipment (UE) to quickly enter the connected state (RRC_CONNECTED state) for data conversation and to reduce the signaling overhead simultaneously brought about by the UE's movement process and state transition process, a new state, namely the non - active state (i.e., RRC_INACTIVE state), has been introduced. In the RRC_INACTIVE state, the non - access stratum (NAS) of the UE remains in the connected state, but the air - interface connection corresponding to the access stratum (AS) of the UE is temporarily interrupted, which is similar to the idle state (i.e., RRC_IDLE state).

Summary of the Invention

[0004] The objective of the embodiments of this disclosure is to provide a method, apparatus, and system for data transmission, as well as a terminal and a network device, in order to realize downlink data transmission of a terminal in the non - active state and reduce the signaling overhead and time - delay consumption in the data transmission process. The specific technical solutions are as follows.

[0005] Embodiments of the present disclosure provide a data transmission method applicable to a target terminal. The method includes: receiving a paging message issued by a target network device for a first time period when the current state of the target terminal is inactive; sending a reactivation request to the target network device when the received paging message includes a designated paging record of the target terminal, such that the target network device sends a downlink small data packet to the target terminal based on the received reactivation request, the designated paging record includes a mobile-terminated small data transmission instruction, and the reason for reactivating in the reactivation request is a mobile-terminated small data transmission; and receiving a downlink small data packet sent by the target network device.

[0006] Embodiments of the present disclosure also provide a data transmission method applicable to a target network device. The method includes: issuing a paging message to a target terminal in accordance with a second time period, wherein the target terminal is currently in an inactive state; receiving a reactivation request sent by the target terminal, which is sent by the target terminal upon receiving a paging message containing a designated paging record of the target terminal itself, wherein the designated paging record contains a mobile-terminated small data transmission instruction, and the reason for reactivating in the reactivation request is a mobile-terminated small data transmission; and sending downlink small data packets to the target terminal based on the reactivation request so that the target terminal receives downlink small data packets.

[0007] Embodiments of the present disclosure also provide a data transmission device applicable to a target terminal. The device comprises: a first receiving module for receiving paging messages issued by a target network device for a first time period when the current state of the target terminal is inactive; a first sending module for sending a reactivation request to the target network device when the received paging message includes a designated paging record of the target terminal, the first sending module so that the target network device sends downlink small data packets to the target terminal based on the received reactivation request, the designated paging record includes a mobile-terminated small data transmission instruction, and the reason for reactivation in the reactivation request is a mobile-terminated small data transmission; and a second receiving module for receiving downlink small data packets sent by the target network device.

[0008] In some embodiments, a paging message includes a paging record list, which is a list for recording the terminals being paged, and this paging record list includes at least one paging record.

[0009] In some embodiments, a paging record includes at least one of the following: terminal identification information of the terminal being paged, access type, or mobile-terminated small data transmission instruction: terminal identification information includes NAS identification information (ID) assigned to the terminal by the Non-Access Layer (NAS) for core network paging and fully inactive terminal identification information for radio access network (RAN) paging; access type is used to indicate whether the paging message is a paging message initiated by a Protocol Data Unit (PDU) session not accessed by the 3rd Generation Partnership Project (3GPP®); and further, mobile-terminated small data transmission instruction is used to indicate that the paging message is used to trigger a mobile-terminated small data transmission.

[0010] In some embodiments, the paging record further includes a non-conflict access preamble indicating that non-conflict random access to the terminal is initiated.

[0011] In some embodiments, the data transmission device further includes: an analysis module for analyzing each paging record in a paging message received after receiving a paging message issued by a target network device according to a first time period; for each paging record obtained by the analysis, a first determination module for determining that the paging record is a designated paging record of the target terminal if the fully inactive terminal identification information in the paging record matches the fully inactive terminal identification information stored by the target terminal and the paging record includes a mobile-terminated small data transmission instruction; and the fully inactive terminal identification information in the paging record matches the fully inactive terminal identification information stored by the target terminal. target The system includes a second determination module for determining that a paging record is not a designated paging record for a target terminal when it does not match fully inactive terminal identification information stored by the terminal, and / or when the paging record does not contain a mobile-terminated small data transmission instruction.

[0012] In some embodiments, the first sending module is used specifically to send a connection resume request to a target network device based on configured grant (CG) configuration information when the received paging message contains a designated paging record for the target terminal, provided that the target terminal has configured grant (CG) configuration information stored.

[0013] In some embodiments, the first sending module is used in particular to send a resume connection request to a target network device in a conflicting access manner when the target terminal does not store configured grant (CG) configuration information, and when the received paging message includes a designated paging record of the target terminal and the designated paging record does not include a conflict-free access preamble; and to send a resume connection request to a target network device in a conflict-free access manner when the received paging message includes a designated paging record of the target terminal and the designated paging record includes a conflict-free access preamble.

[0014] In some embodiments, the data transmission device further includes a determination module for determining whether a target terminal currently satisfies a preset connection initiation condition before sending a connection resumption request to a target network device, wherein the preset connection initiation condition is that a mobile-terminated small data transmission instruction is received, or that a mobile-terminated small data transmission instruction is received and the downlink reference signal receiving power (RSRP) is greater than a preset threshold; and an implementation module for performing the step of sending a connection resumption request to a target network device when the target terminal satisfies the preset connection initiation condition.

[0015] In some embodiments, the data transmission device further includes an implement module for sending another connection resumption request when another preset connection initiation condition is met, thereby causing the target terminal to send uplink data packets to the target network device after the connection corresponding to another connection resumption request has been reactivated, wherein the other preset connection initiation condition is that the data volume of a radio bearer configured for Mobile Originated Small Data Transmission is below a preset data volume threshold, or the other preset connection initiation condition is that the data volume of a radio bearer configured for Mobile Originated Small Data Transmission is below a preset data volume threshold and the uplink small data transmission resource is enabled.

[0016] In some embodiments, the preset connection initiation condition is the receipt of a mobile-terminated small data transmission instruction; or the receipt of a mobile-terminated small data transmission instruction and Wireless resource control ( RRC (Radio Resource Control) The lower layers below the main layer are Mobile Terminate This can be expressed as indicating that the trigger condition for sending small data has been met.

[0017] In some embodiments, a different preset connection start condition is 、R R C layer A higher layer requested the resumption of the RRC connection. System Information Block Type 1 SIB1 :System Information Block Type 1) This includes a common configuration for small data transmission, a small data transmission configuration is configured, all uplink small data is mapped to the wireless bearer of the small data transmission configuration, and the lower layers below the RRC layer are, Mobile-Originated. This can be expressed as indicating that the trigger condition for sending small data has been met.

[0018] In some embodiments, the data transmission device further comprises: a first start module that starts a timer for detecting the restart process of small data transmission in an inactive state when a target terminal satisfies preset connection start conditions; and a second start module that starts a timer for monitoring the restart process in an inactive state and for sending a timeout indicator to a MAC entity when the target terminal does not satisfy the preset connection start conditions, the timeout indicator being used to indicate a timeout of the configured grant (CG) timing advance timer in the CG configuration information of the small data transmission.

[0019] In some embodiments, the data transmission device further includes a release module for releasing stored configured grant (CG) configuration information when a target terminal moves from the current radio access network (RAN) cell to another RAN cell and initiates a connection reactivation process within the other RAN cell.

[0020] In some embodiments, the resumption request is either a first or second resumption request, and the first transmitting module is used to: select the first resumption request as the resumption request when the SIB1 transmitted by the base station indicates that the resumption request uses a full resume identifier, or select the second resumption request as the resumption request when the received SIB1 does not indicate the use of a full resume identifier; to restore preset security information from stored access layer context information, the preset security information includes radio resource control (RRC) configuration, robust header compression (ROHC) status, stored mapping relationships between quality of service (QoS) flows and data resource bearers (DRBs), base station root keys, and integrity protection keys; and the first transmitting module further uses the Packet Data Convergence Protocol (PDCP) of the SIB1. It is used in particular to reconstruct the Protocol entity; to restore SIB1; to reactivate the configuration associated with the primary cell group and Radio Link Control (RLC) bearer of the PDCP configuration from the access layer context information for each radio bearer configured for mobile-terminated small data transmission, and to reconstruct the PDCP entity of that radio bearer; to reactivate all radio bearers configured for mobile-terminated small data transmission; and to send a connection reactivation request to the target network device.

[0021] In some embodiments, the first and second connection reactivation requests each include a reactivation identifier, a reactivation integrity check code, and a reason for reactivating the connection, wherein the reactivation identifier of the first connection reactivation request is a fully inactive terminal identification information stored by the target terminal, and the reactivation identifier of the second connection reactivation request is a shortened inactive terminal identification information stored by the target terminal, the fully inactive terminal identification information and the shortened inactive terminal identification information are radio network temporary identifier values ​​of the inactive terminal, and are used by the target network to find the anchor point before the terminal entered the inactive state and the access layer context information stored by the anchor point, the fully inactive terminal identification information and the shortened inactive terminal identification information are of different sizes; the reactivation integrity check code is an identification information authentication token for terminal identification information authentication at the base station.

[0022] In some embodiments, the data transmission device further comprises: a third receiving module for receiving a first release message issued by a target network device when the current state of the target terminal is connected, wherein the first release message includes suspension configuration information indicating that the terminal should implement an inactive state configuration; and a first switching module for switching the current state to an inactive state based on the suspension configuration information.

[0023] In some embodiments, the suspension configuration information includes fully inactive terminal identification information, shortened inactive terminal identification information, wireless paging period, wireless notification area information, timer, next-hop chaining count value, and mobile-terminated small data transmission configuration information.

[0024] In some embodiments, the fully inactive state terminal identification information and the shortened inactive state terminal identification information are radio network temporary identifier values of terminals in the inactive state, and are used by the target network side to find the anchor point node before the terminal enters the inactive state and the access layer context information stored by the anchor point node. The fully inactive state terminal identification information and the shortened inactive state terminal identification information have different sizes; the radio paging period is a RAN paging period configured by a radio access network (RAN) side node for a terminal in the inactive state; the radio notification area information includes a cell list and a radio area configuration list. The cell list is a list of cells configured by the RAN area as and the radio area configuration list includes a RAN area code or a RA code of the RAN area; the timer is used to trigger a periodic RAN-based notification area update (RNAU) process in the terminal; the next-hop chaining count value is used to calculate a security key after the connection is resumed; the configuration information for mobile terminated small data transmission is Mobile Terminate at least one of a data radio bearer (DRB) list for small data transmission or Mobile Terminate a signaling radio bearer 2 (SRB2) indication for small data transmission, Mobile Terminate the DRB list for small data transmission indicates the DRB identifier of the small data transmission configuration, Mobile Terminate and the SRB2 indication for small data transmission indicates the presence or absence of SRB2 in the small data transmission configuration of the terminal.

[0025] In some embodiments, the configuration information for mobile terminated small data transmission further includes configured grant (CG) configuration information, and the CG SuccessThe report includes the CG SSB RSRP threshold, the CG Timing Advance Timer, the CG Timing Advance Verification Configuration, and the CG RSRP Variation Threshold, where: the CG SSB RSRP threshold is the reference signal received power (RSRP) threshold selected by the SSB performing small data transmissions based on CG resources; the CG Timing Advance Timer is used for timing synchronization of small data transmissions; the CG Timing Advance Verification Configuration is used for configuring timing advance (TA) verification based on RSRP; and the CG RSRP Variation Threshold is the RSRP threshold for TA verification of small data transmissions.

[0026] In some embodiments, the first switching module: resets Media Access Control (MAC) to release the default MAC cell group configuration; applies suspension configuration information; and, when the suspension configuration information includes CG configuration information, each DRB in the DRB list for inactive small data transmissions Mobile Terminate SRB2 instruction for small data transmission SRB2 in and Mobile TerminateTo determine the DRB and SRB2 during the small data transmission process, to reconstruct the RLC entity for each Radio Link Layer Control Protocol (RLC) bearer in the target terminal configuration, to trigger the Packet Data Convergence Protocol (PDCP) entity, to perform the Session Data Unit (SDU) discard process for the restarted SRB2 and SRB1, to configure the CG resource for small data transmission for the MAC entity, and to indicate that the CG timing advance timer has been started; the current Access Layer Root Key (KgNB) and Integrity Protection Key (KRRCint) of the Radio Resource Control (RRC) signaling, the Robust Header Compression (ROHC) state, the stored mapping rules between the Quality of Service (QoS) flow and the Data Resource Bearer (DRB), the Cell Radio Network Temporary Identifier (C-RNTI) used in the Source Primary Cell (PCell), the cell identifier and physical cell identifier of the Source PCell, and the New Radio Primary Secondary Cell (NR) It is used to store all configuration parameters except for the Service Cell Common Configuration SIB, which includes the Special Cell (SpCell) common configuration in the synchronous reconfiguration message of a PSCell (New Radio Primary Secondary Cell), the parameters in the synchronous reconfiguration message of a PCell, the parameters in the synchronous reconfiguration message of an NR PSCell, the mobility control information of the Secondary Cell Group (SCG) of an E-UTRA PSCell, the Primary Secondary Cell (PSCell) configuration of an EN-DC, and the access layer context information of an inactive terminal; to suspend all SRBs except SRB0 and DRB; to indicate that PDCP suspension should be implemented in the lower layers below the RRC layer for all DRBs; and to switch to an inactive state and perform cell reselection.

[0027] In some embodiments, the data transmission device further comprises a fourth receiving module for receiving a system message broadcast by a target network device, the system message including at least one of downlink transmission frequency information, an initial downlink bandwidth part (BWP), broadcast control channel (BCCH) configuration information, or paging channel (PCCH) configuration information.

[0028] In some embodiments, downlink transmit frequency information is used to indicate the transmit frequency of downlink small data packets; initial downlink BWP is the initial downlink BWP configuration of the primary cell; BCCH configuration information is a configuration related to correcting the passing period of system messages; PCCH configuration information is the default paging period, paging frame number and configuration, the number of paging occasions, and the first physical downlink control channel (PDCCH). The Channel includes monitoring occasions, the default paging period is the default paging period broadcast in system messages, the paging frame number and configuration are used to derive the total number of paging frames and the paging frame offset, the number of paging occasions is used to indicate the number of paging occasions in each paging frame, a paging occasion is a group of PDCCH monitoring occasions consisting of multiple time slots for sending paging control information, and the first PDCCH monitoring occasion is the first PDCCH monitoring occasion to indicate monitoring the paging occasion of a paging frame.

[0029] In some embodiments, the data transmission device includes a third determination module for determining the smaller of the radio paging period and the default paging period as a first time period for receiving paging messages when the target terminal is inactive, wherein the radio paging period is the RAN paging period configured by the radio access network (RAN) side node for the inactive terminal.

[0030] In some embodiments, the connection resumption request further includes an uplink small data packet; a second receiving module is specifically used to receive a downlink small data packet sent by the target network device and feedback information sent by the target network device in response to the uplink small data packet.

[0031] In some embodiments, the data transmission device further comprises a fifth receiving module for receiving a second release message sent by a target network device when the transmission of a downlink small data packet is complete, wherein the second release message includes instruction information indicating a state switch; and a second switching module for switching the current state to an inactive or idle state based on the instruction information.

[0032] Embodiments of the present disclosure also provide a data transmission device applicable to a target network device. The data transmission device comprises: a second dispatch module for issuing paging messages to a target terminal according to a second time period, wherein the target terminal is currently in an inactive state; a sixth receiving module for receiving a reactivation request dispatched by the target terminal, wherein the reactivation request is dispatched by the target terminal upon receiving a paging message containing a designated paging record of the target terminal itself, wherein the designated paging record contains a mobile-terminated small data transmission instruction, and the reason for reactivation in the reactivation request is a mobile-terminated small data transmission; and a third dispatch module for dispatching downlink small data packets to the target terminal based on the reactivation request so that the target terminal receives downlink small data packets.

[0033] In some embodiments, a paging message includes a paging record list, which is a list for recording the terminals being paged, and this paging record list includes at least one paging record.

[0034] In some embodiments, a paging record includes at least one of terminal identification information for the terminal being paged, an access type, or a mobile-terminated small data transmission instruction: terminal identification information includes NAS identification information (ID) assigned to the terminal by the Non-Access Layer (NAS) for core network paging and fully inactive terminal identification information for radio access network (RAN) paging; access type is used to indicate whether the paging message is a paging message initiated by a protocol data unit (PDU) session not accessed by the Third Generation Partnership Project (3GPP); and mobile-terminated small data transmission instruction is used to indicate that the paging message is used to trigger a mobile-terminated small data transmission.

[0035] In some embodiments, the paging record further includes a non-conflict access preamble indicating that non-conflict random access to the terminal is initiated.

[0036] In some embodiments, the reconnection request is either a first reconnection request or a second reconnection request, the first being sent by the target terminal when an SIB1 sent by the base station indicates that the reconnection request uses a full reconnection identifier, and the second being sent by the target terminal when an SIB1 sent by the base station does not indicate that the reconnection request uses a full reconnection identifier.

[0037] In some embodiments, the first and second connection reactivation requests each include a reactivation identifier, a reactivation integrity check code, and a reason for reactivating the connection, wherein the reactivation identifier of the first connection reactivation request is a fully inactive terminal identification information stored by the target terminal, and the reactivation identifier of the second connection reactivation request is a shortened inactive terminal identification information stored by the target terminal, the fully inactive terminal identification information and the shortened inactive terminal identification information are radio network temporary identifier values ​​of the inactive terminal, and are used by the target network to find the anchor point before the terminal entered the inactive state and the access layer context information stored by the anchor point, the fully inactive terminal identification information and the shortened inactive terminal identification information are of different sizes; the reactivation integrity check code is an identification information authentication token for terminal identification information authentication at the base station.

[0038] In some embodiments, the data transmission device sends a first release message target The system further comprises a fourth transmission module for issuing messages to a terminal, wherein the first release message includes suspension configuration information indicating that the terminal should perform an inactive state configuration, thereby causing the target terminal to switch its current state to an inactive state based on the suspension configuration information.

[0039] In some embodiments, the suspension configuration information includes fully inactive terminal identification information, shortened inactive terminal identification information, wireless paging period, wireless notification area information, timer, next-hop chaining count value, and mobile-terminated small data transmission configuration information.

[0040] In some embodiments, the fully inactive terminal identification information and the abbreviated inactive terminal identification information are wireless network temporary identifier values ​​of the inactive terminal, used by the target network to find the anchor point node before the terminal entered the inactive state and the access layer context information stored by the anchor point node, and the fully inactive terminal identification information and the abbreviated inactive terminal identification information differ in size; the wireless paging period is the RAN paging period configured by the wireless access network (RAN) side node for the inactive terminal; the wireless notification area information includes a cell list and a wireless area configuration list, the cell list being the RAN area as A list of configured cells, the wireless area configuration list is the RAN area code, or the RAN area RA The code includes; the timer is used to trigger a periodic RAN-based notification area update (RNAU) process on the terminal; the next-hop chaining count value is used to calculate the security key after the connection is resumed; the mobile-terminated small data transmission configuration information is used for the inactive small data transmission data resource bearer (DRB) list or Mobile Terminate The DRB list for a small data transmission, which includes at least one of the signaling radio bearer 2 (SRB2) instructions for small data transmissions, indicates the DRB identifier for the small data transmission configuration. Mobile Terminate The SRB2 instruction for small data transmission indicates whether or not SRB2 is enabled in the terminal's small data transmission configuration.

[0041] In some embodiments, the configuration information for mobile-terminated small data transmission further includes configured grant (CG) configuration information, and the CG configuration SuccessThe report includes the CG SSB RSRP threshold, CG Timing Advance Timer, CG Timing Advance Verification Configuration, and CG RSRP Variation Threshold: the CG SSB RSRP threshold is the reference signal received power (RSRP) threshold selected by the SSB performing small data transmissions based on CG resources; the CG Timing Advance Timer is used for timing synchronization of small data transmissions; the CG Timing Advance Verification Configuration is used for configuring timing advance (TA) verification based on RSRP; and the CG RSRP Variation Threshold is the RSRP threshold for TA verification of small data transmissions.

[0042] In some embodiments, the data transmission device further comprises a broadcast module for broadcasting a system message, the system message including at least one of downlink transmission frequency information, initial downlink bandwidth (BWP), broadcast control channel (BCCH) configuration information, or paging channel (PCCH) configuration information.

[0043] In some embodiments, downlink transmit frequency information is used to indicate the transmit frequency of downlink small data packets; initial downlink BWP is the initial downlink BWP configuration of the primary cell; BCCH configuration information is a configuration related to correcting the passing period of system messages; PDCCH configuration information includes the default paging period, paging frame number and configuration, the number of paging occasions, and the first physical downlink control channel (PDCCH) monitoring occasion, the default paging period being broadcast in system messages. The paging period is used to derive the total number of paging frames and the paging frame offset, the number of paging occasions is used to indicate the number of paging occasions in each paging frame, a paging occasion is a group of PDCCH monitoring occasions consisting of multiple time slots for sending paging control information, and the first PDCCH monitoring occasion is the first PDCCH monitoring occasion to indicate monitoring the paging occasions of a paging frame.

[0044] In some embodiments, the data transmission device further comprises a fourth determination module that determines a default paging period as a second time period for sending paging messages.

[0045] In some embodiments, the reconnection request further includes an uplink small data packet, and a third transmission module is used in particular to: generate feedback information for the uplink small data packet and to acquire a downlink small data packet when a reconnection request is received; and to transmit the downlink small data packet and feedback information to a target terminal.

[0046] In some embodiments, the data transmission device further includes a fifth transmission module for sending a second release message to a target terminal when the transmission of a downlink small data packet is complete, the second release message including instruction information indicating a state switch, so that the target terminal switches its current state to an inactive or idle state based on the instruction information.

[0047] Embodiments of this disclosure also provide a data transmission system comprising a target terminal and a target network device. The target terminal is used to carry out any of the above data transmission methods applicable to the target terminal, and the target network device is used to carry out any of the above data transmission methods applicable to the target network device.

[0048] Embodiments of the present disclosure also provide a target terminal comprising a processor, a communication interface, memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus. The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory to perform any of the data transmission methods described above.

[0049] Embodiments of the present disclosure also provide a target network device comprising a processor, a communication interface, memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus. The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory to perform any of the data transmission methods described above.

[0050] Embodiments of this disclosure also provide a computer-readable storage medium that stores a computer program which, when executed by a processor, performs one of the data transmission methods described above.

[0051] Embodiments of this disclosure also provide a computer program product that, when executed on a computer, includes instructions causing the computer to perform one of the data transmission methods described above.

[0052] The embodiments of this disclosure have the following beneficial effects.

[0053] A technical solution provided in embodiments of this disclosure allows a reactivation request to be sent to a target network device when the target terminal is in an inactive state, such that the target terminal receives a paging message containing a designated paging record for the target terminal itself, sent by the target network device, triggering a small data transmission process between the target terminal and the target network device when the terminal is in an inactive state. The target network device can then send downlink small data packets to the target terminal based on the received reactivation request, and the target terminal also receives the downlink small data packets, thereby enabling the downlink small data packet transmission process for the inactive terminal.

[0054] Furthermore, compared to related technologies in which an inactive terminal must switch to a connected state for data transmission, embodiments of the present disclosure introduce a new terminal access type, namely mobile-terminated small data transmission, through a mobile-terminated small data transmission instruction in a designated paging record, so that the terminal can receive downlink small data packets sent by a target network device while in an inactive state. This avoids the signaling overhead and latency consumption resulting from switching from an inactive state to a connected state, improves the transmission efficiency of downlink small data packets, saves signaling overhead for downlink small data packets, and thus effectively reduces signaling overhead and latency consumption in the data transmission process.

[0055] Of course, it is not necessary to achieve all of the above-mentioned benefits simultaneously by implementing any of the products or methods disclosed herein.

[0056] To more clearly illustrate the embodiments of this disclosure or the technical solutions in the prior art, the accompanying drawings that may be used in describing the embodiments or the prior art are briefly presented below. Naturally, the accompanying drawings described below represent only a portion of the embodiments of this disclosure. Those skilled in the art will also be able to obtain other embodiments from these accompanying drawings. [Brief explanation of the drawing]

[0057] [Figure 1] This is a first schematic flowchart of a data transmission method provided by an embodiment of the present disclosure. [Figure 2] This is a second schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 3] This is a third schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 4]This is a fourth schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 5] This is a fifth schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 6] This is a sixth schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 7] This is a schematic flowchart of the connection resumption request transmission method provided by the embodiments of this disclosure. [Figure 8] This is a seventh schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 9] This is an eighth schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 10] This is a ninth schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 11] This is a tenth schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 12] This is an eleventh schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 13] This is a twelfth schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 14] This is a thirteenth schematic flowchart of the data transmission method provided by the embodiments of this disclosure. [Figure 15] This is a signaling diagram of the data transmission process in an inactive state provided by embodiments of this disclosure. [Figure 16] This is a first schematic diagram showing a data transmission device provided by an embodiment of the present disclosure. [Figure 17] This is a second schematic diagram showing a data transmission device provided by an embodiment of the present disclosure. [Figure 18] This is a schematic diagram illustrating a data transmission system provided by embodiments of this disclosure. [Figure 19] This is a schematic diagram showing a target terminal provided by an embodiment of this disclosure. [Figure 20] This is a schematic diagram showing a target network device provided by embodiments of this disclosure. [Modes for carrying out the invention]

[0058] The technical solutions in the embodiments of this disclosure will be described clearly and completely below, together with the accompanying drawings of the embodiments of this disclosure. More precisely, the embodiments described are not all embodiments, but only a selection of the embodiments of this disclosure. Based on the embodiments of this disclosure, all other embodiments that can be obtained by those skilled in the art based on this disclosure are within the scope of this disclosure.

[0059] In related technologies, if a UE in the RRC_INACTIVE state needs to send a small data packet, the UE must first switch from the RRC_INACTIVE state to the RRC_CONNECTED state, meaning the data is sent only after a connection has been established between the network's control plane and user plane. This process results in increased signaling overhead and time delay consumption.

[0060] To solve problems in related technologies, embodiments of the present disclosure provide a data transmission method. As shown in Figure 1, Figure 1 is a first schematic flowchart of the data transmission method provided by embodiments of the present disclosure. The method shown in Figure 1 is applied to a target terminal and includes, in detail, the following steps.

[0061] In step S101, when the current state of the target terminal is inactive, a paging message issued by the target network device is received according to a first time period.

[0062] In step S102, if the received paging message contains a specified paging record of the target terminal, a resume request is sent to the target network device, which then sends downlink small data packets to the target terminal based on the received resume request. The specified paging record contains a mobile-terminated small data transmission instruction, and the reason for resume in the resume request is mobile-terminated small data transmission.

[0063] In step S103, the downlink small data packet sent by the target network device is received.

[0064] In embodiments of this disclosure, the target network device may be a network device such as a base station accessed by a target terminal, and the target terminal may be any terminal (e.g., an electronic device such as a cell phone or tablet) within the network coverage range corresponding to the target network device. Here, the target network device and target terminal are not particularly limited. For ease of understanding, the following description will, for example, assume that the target terminal is a UE and the target network device is a base station of a 5th Generation Mobile Communication Technology (5G) core network, without limiting the results.

[0065] As shown in Figure 1, when the target terminal is in an inactive state, if the target terminal receives a paging message issued by the target network device containing a designated paging record for the target terminal itself, a reactivation request can be sent to the target network device to trigger the small data transmission process between the target terminal and the target network device when the terminal is in an inactive state. At this time, the target network device can send downlink small data packets to the target terminal based on the received reactivation request, and the target terminal also receives the downlink small data packets, thereby enabling the downlink small data packet transmission process for the inactive terminal.

[0066] Furthermore, compared to related technologies in which an inactive terminal must switch to a connected state for data transmission, embodiments of the present disclosure introduce a new terminal access type, namely mobile-terminated small data transmission, through a mobile-terminated small data transmission instruction in a designated paging record, so that the terminal can receive downlink small data packets sent by a target network device while in an inactive state. This avoids the signaling overhead and latency consumption resulting from switching from an inactive state to a connected state, improves the transmission efficiency of downlink small data packets, saves signaling overhead for downlink small data packets, and thus effectively reduces signaling overhead and latency consumption in the data transmission process.

[0067] Embodiments of this disclosure will be described below with reference to specific embodiments.

[0068] In step S101 described above, that is, when the current state of the target terminal is inactive, the paging message sent by the target network device is received according to the first time period.

[0069] In embodiments of the present disclosure, during the terminal's data service transmission process, the terminal may be in one of three states: connected (i.e., RRC_CONNECTED), inactive (i.e., RRC_INACTIVE), or idle (i.e., RRC_IDLE).

[0070] When any terminal accessing the network corresponding to the target network device is in the inactive state described above, the target network device itself cannot recognize the inactive state and therefore considers the terminal to be connected. The target network device can send paging messages to the target terminal, which is considered to be connected, according to a preset time period (recorded as the second time period). In response, the target terminal can receive the paging messages sent by the target network device according to a preset time period (recorded as the first time period).

[0071] In some embodiments, the above paging message may include a paging record list. The paging record list is a list for recording the terminals being paged, and the paging record list includes at least one paging record.

[0072] In some embodiments, each paging record included in the above-described paging message may include at least one of the following: terminal identification information of the paged terminal, access type, or mobile-terminated small data transmission instruction.

[0073] For example, a paging record may include the terminal identification information, access type, or mobile-terminated small data transmission instruction of the paged terminal. In another example, a paging record may include the terminal identification information and access type of the paged terminal, or the terminal identification information and mobile-terminated small data transmission instruction of the paged terminal, or the access type and mobile-terminated small data transmission instruction. In yet another example, a paging record may include the terminal identification information, access type, and mobile-terminated small data transmission instruction of the paged terminal.

[0074] Terminal identification information may include the NAS ID assigned to the terminal by the NAS for core network paging and fully inactive terminal identification information for RAN paging (recorded as Full I-RNTI). The above access type is used to indicate whether the paging message is initiated by a PDU session not accessed by 3GPP. The mobile-terminated small data transmission instruction is used to indicate that the paging message is used to trigger a mobile-terminated small data transmission.

[0075] The Full I-RNTI mentioned above is the terminal identification information for an inactive target terminal. In addition, the above access type may include multiple access types. Depending on the different access type, the reason for reactivating the connection changes during the process in which the RRC connection reactivation process is initiated by the paged terminal corresponding to the paging record.

[0076] Regarding the access type of the paging record mentioned above, the value corresponding to the access type may include the following:

[0077] In the first case, when the value corresponding to the access type is 1 (recorded as access type 1), the terminal is instructed to initiate the RRC connection resumption process, and the reason for resuming the connection is set to Multimedia Priority Service (MPS) priority access.

[0078] In the second case, when the value corresponding to the access type is 2 (recorded as access type 2), the terminal is instructed to initiate the RRC connection reactivation process, and the reason for reactivation is set as Modulation Coding Scheme (MCS) preferred access.

[0079] In the third case, when the value corresponding to the access type is an integer between 11 and 15 (recorded as access types 11 through 15 respectively), the terminal is instructed to initiate the RRC connection resumption process, and the reason for resuming the connection is set to high-priority access.

[0080] In the fourth case, when the value corresponding to the access type is, for example, any integer N between 4 and 10 (recorded as access type N), the terminal is instructed to initiate the RRC connection resumption process, and the reason for resuming the connection is set to mobile terminated small data transmission.

[0081] In the fifth case, if the value corresponding to the access type is a value other than the value corresponding to the access type in the first to fourth cases above, for example, 3, the terminal is instructed to start the RRC connection resumption process, and the reason for resuming the connection is set to downlink access.

[0082] In the cases 1 through 5 described above, when the fourth case is met, the paged terminal corresponding to the paging record begins transmitting small data in the inactive state process. That is, the step of sending a connection resume request to the target network device in step S102 is performed. The value corresponding to the access type in the fourth case described above is set in advance on the terminal and can be set specifically according to user needs, etc., and is not particularly limited here.

[0083] In some embodiments, in addition to the terminal identification information, access type, and mobile-terminated small data transmission instruction described above, each paging record included in the paging message may also include a conflict-free access preamble that instructs the terminal to initiate conflict-free random access.

[0084] When the above paging record includes the above-mentioned no-conflict access preamble, it means that the target network device has assigned the no-conflict access preamble to the paged terminal corresponding to the paging record. In this case, the terminal can initiate no-conflict random access based on the no-conflict access preamble. When the above paging record does not include the above-mentioned no-conflict access preamble, it means that the target network device has not assigned the no-conflict access preamble to the paged terminal corresponding to the paging record, and in this case, the terminal needs to initiate conflicted random access. Conflict-free random access and conflicted random access initiated by terminals can be found in the following explanations and are not specifically explained here.

[0085] In embodiments of this disclosure, the second time period may be greater than or equal to the first time period in order to reduce the chance that a paged terminal will not receive a paging message issued by a target network device within a given time. That is, the time period for the target network device to issue a paging message is greater than or equal to the time period for the target terminal to receive a paging message. Here, the first and second time periods are not particularly limited.

[0086] With respect to step S102 above, that is, when the received paging message contains a designated paging record of the target terminal, a connection resume request is sent to the target network device, which then sends downlink small data packets to the target terminal based on the received connection resume request. The designated paging record contains a mobile-terminated small data transmission instruction, and the reason for connection resume in the connection resume request is mobile-terminated small data transmission.

[0087] In this step, after receiving the paging message sent by the target network device described above, the target terminal can determine whether the paging message contains the target terminal's own designated paging record. If the paging message contains the target terminal's designated paging record, the designated paging record contains a mobile-terminated small data transmission instruction, and the target terminal can initiate the RRC connection resume process, i.e., the mobile-terminated small data transmission process. At this point, the target terminal can send a connection resume request, i.e., an RRC connection resume request, to the target network device. The determination of the designated paging record can be found in the following explanation and is not specifically explained here.

[0088] In embodiments of this disclosure, the above-mentioned reactivation request records the reactivation reason. Depending on the different access types in the above-mentioned paging record, the reason for sending a reactivation request will also differ when the terminal initiates the RRC reactivation process. For example, in step S102 above, the target terminal initiates a mobile-terminated small data transmission process, in which case the reactivation reason is an inactive downlink (small) data transmission, i.e., a mobile-terminated small data transmission (MT-SDT). When the target network device receives the reactivation request, it may decide to trigger the mobile-terminated small data transmission process depending on the reactivation reason recorded in the reactivation request. In this case, the target network device may send downlink data to the target terminal in the form of downlink small data packets.

[0089] In some embodiments, when the amount of downlink data is less than a first data volume threshold, the target network device can send the downlink data to the target terminal as a single downlink small data packet.

[0090] In another embodiment, when the amount of downlink data exceeds the first data volume threshold, the target network device can divide the downlink data into multiple downlink small data packets, each with a data volume less than or equal to the first data volume threshold, and send each of the resulting downlink small data packets to a target terminal.

[0091] In embodiments of this disclosure, the above data transmission between an inactive target terminal and a target network device is an inactive MT-SDT, and therefore the amount of data in each downlink small data packet sent to the target terminal by the target network device is less than or equal to a first data volume threshold. The above first data volume threshold can be set according to user needs, channel bandwidth, channel bearing capacity, etc. Here, the above first data volume threshold is not particularly limited.

[0092] Depending on the different amounts of downlink data described above, the number of downlink small data packets sent by the target network device to the target terminal may be one or more. The number of downlink small data packets is not particularly limited.

[0093] In some embodiments, if the received paging message does not contain the target terminal's designated paging record, the target terminal can determine that it is not a terminal that was paged by the target network device. In this case, the target terminal does not perform any processing; that is, the target terminal does not send a reactivation request whose reactivation reason is a mobile-terminated small data transmission to the target network device.

[0094] Regarding step S103 above, that is, the downlink small data packet sent by the target network device is received.

[0095] In this step, the target network device sends the downlink small data packets described above to the target terminal, and the target terminal receives those downlink small data packets. Depending on the different amounts of downlink data described above, the number of downlink small data packets received by the target terminal will also vary. The step of the target terminal receiving the downlink small data packets described above will not be described in detail here.

[0096] In some embodiments, the embodiments of the present disclosure also provide a data transmission method according to the method shown in Figure 1. As shown in Figure 2, Figure 2 is a second schematic flowchart of the data transmission method provided by the embodiments of the present disclosure. This method includes the following steps:

[0097] In step S201, when the current state of the target terminal is inactive, a paging message issued by the target network device is received according to a first time period.

[0098] Step S201 described above is the same as step S101 described above.

[0099] In step S202, each paging record in the received paging message is parsed.

[0100] In this step, for each paging record in the received paging message, the target terminal can analyze the information contained in that paging record to determine information such as terminal identification information or access type contained in that paging record.

[0101] In embodiments of this disclosure, the information parsed by the target terminal also changes depending on the different information contained in each paging record. Here, the information parsed in each paging record is not particularly limited.

[0102] In step S203, for each parsed paging record obtained by the parsing, if the fully inactive terminal identification information in this paging record matches the fully inactive terminal identification information stored by the target terminal, and if this paging record contains a mobile-terminated small data transmission instruction, it is determined that this paging record is the designated paging record of the target terminal.

[0103] In embodiments of this disclosure, the target terminal can store fully inactive terminal identification information corresponding to the target terminal. For each parsed paging record obtained by parsing, the target terminal can compare the fully inactive terminal identification information parsed for this paging record (i.e., Full I-RNTI in the paging record) with its stored fully inactive terminal identification information, and determine whether the information parsed for this paging record includes a mobile-terminated small data transmission instruction. Based on the match result and the determination result, it can determine whether this paging record is the designated paging record of the target terminal. The fully inactive terminal identification information stored in the target terminal can be described below and is not specifically described here.

[0104] The above matching results and judgment results include at least the following cases:

[0105] In the first case, the fully inactive terminal identification information in the paging record is the same as the fully inactive terminal identification information stored by the target terminal, and the information parsed from the paging record includes a mobile-terminated small data transmission instruction.

[0106] In the second case, the fully inactive terminal identification information in the paging record is the same as the fully inactive terminal identification information stored by the target terminal, but the information parsed from the paging record does not include the mobile-terminated small data transmission instruction.

[0107] In the third case, the fully inactive terminal identification information in the paging record differs from the fully inactive terminal identification information stored by the target terminal, but the information parsed from the paging record includes a mobile-terminated small data transmission instruction.

[0108] In the fourth case, the fully inactive terminal identification information in the paging record differs from the fully inactive terminal identification information stored by the target terminal, and the information parsed from the paging record does not include mobile-terminated small data transmission instructions.

[0109] In the four cases described above, when the first case is met, the target terminal can determine that the paging record is the designated paging record of the target terminal itself.

[0110] In step S204, the fully inactive terminal identification information in this paging record is target If the paging record does not match the fully inactive state terminal identification information stored by the terminal, and / or if the paging record does not contain a mobile-terminated small data transmission instruction, it is determined that this paging record is not the designated paging record for the target terminal.

[0111] In the four cases shown in step S203 above, if any of the second, third, or fourth cases above is met, the target terminal can determine that this paging record is not the designated paging record of the target terminal itself.

[0112] If a paging message received by a target terminal is determined to contain a paging record that is not a designated paging record for the target terminal itself, the target terminal can determine that the paging message does not contain a designated paging record for the target terminal itself.

[0113] In embodiments of the present disclosure, the target terminal performs step S203 or step S204, respectively, depending on separate matches between fully inactive terminal identification information in each paging record within a paging message and fully inactive terminal identification information stored by the target terminal, and depending on separate cases where each paging record includes a mobile-terminated small data transmission instruction. Herein, performing steps S203 and S204 is not particularly limited.

[0114] In some embodiments, when the paging record in the above-described paging message satisfies the second of the four cases in step S203 above, that is, when the fully inactive terminal identification information in the paging record is the same as the fully inactive terminal identification information stored by the target terminal, but the information parsed from the paging record does not include a mobile-terminated small data transmission instruction, the target terminal can determine that it itself is a terminal that has been paged by the target network device. At this time, the target terminal can initiate the RRC connection reactivation process according to the value corresponding to the access type in the paging message, in the manner shown in the first, second, third, or fifth of the five cases shown in step S101 above. The reactivation reason in the connection reactivation request is the same as the value corresponding to the access type, which is not specifically described here.

[0115] In another embodiment, if the paging record in the above paging message satisfies the third or fourth of the four cases in step S203 above, the fully inactive terminal identification information in the paging record is different from the fully inactive terminal identification information stored by the target terminal, and the target terminal can be determined not to be a terminal that was paged by the target network device itself. In this case, the target terminal does not need to perform any processing.

[0116] Steps S202-S204 above enable the target terminal to accurately determine whether the received paging message contains a specified paging record for the target terminal itself, and if the paging message contains a specified paging record, it can initiate the mobile-terminated small data transmission process, thereby ensuring that the target terminal initiates the downlink small data transmission process.

[0117] In step S205, if the received paging message contains a specified paging record of the target terminal, a resume request is sent to the target network device, which then sends downlink small data packets to the target terminal based on the received resume request. The specified paging record contains a mobile-terminated small data transmission instruction, and the reason for resume in the resume request is mobile-terminated small data transmission.

[0118] In step S206, the downlink small data packet sent by the target network device is received.

[0119] Steps S205 to S206 above are the same as steps S102 to S103 above.

[0120] In some embodiments, the target terminal may store CG configuration information, which refers to configured grant resources configured for small data transmission. The CG configuration information stored in the target terminal can be found in the following description and is not specifically described here.

[0121] In embodiments of the present disclosure, the above-described CG configuration information can be used for configured grant resource configuration during the uplink small data transmission process between the target terminal and the target network device, and can also be used for configured grant resource configuration during the downlink small data transmission process between the target terminal and the target network device.

[0122] In some embodiments, when the target terminal stores CG configuration information in accordance with the method shown in Figure 1, embodiments of the present disclosure also provide a data transmission method. As shown in Figure 3, Figure 3 is a third schematic flowchart of the data transmission method provided by embodiments of the present disclosure. In the method shown in Figure 3, step S102 above is refined into the following step, namely step S1021.

[0123] In step S1021, when the received paging message contains the specified paging record of the target terminal, a connection resume request is sent to the target network device based on the CG configuration information.

[0124] In this step, since the target terminal stores CG configuration information, the target terminal can initiate small data transmission in the inactive state process using the configured grant method based on the CG configuration information stored in the target terminal. That is, the target terminal can configure SDT based on the CG configuration information to configure small data transmission to the target terminal's initial BWP, or to the target terminal's normal uplink (NUL) carrier and supplementary uplink (SUL) carrier.

[0125] In some embodiments, with respect to CG configuration information stored by the target terminal, if the target terminal moves from the current RAN cell to another RAN cell and initiates a connection reactivation process in the other RAN cell, the stored CG configuration information is released. That is, the SDT resources configured by the target terminal based on the CG configuration information are only valid in the cell where the target terminal receives an RRC release message (recorded as a first release message) and transitions to an RRC inactive state. Receiving the first release message can be found in the following explanation and will not be specifically explained here.

[0126] For ease of understanding, let's take the RAN cell where the target terminal is currently located as cell A. At a given moment, as the user moves, the target terminal accesses another RAN cell, for example, cell B. The configured grant (CG) configuration information received and stored by the target terminal in cell A is not used to initiate the connection reactivation process in cell B. The term "cell" above is an abbreviation for base station cell (sometimes referring to cellular cell).

[0127] By step S1021 described above, the target terminal can initiate small data transmission in the inactive state process using the CG configured grant method, based on the CG configuration information stored in the target terminal.

[0128] In some embodiments, when the target terminal does not store the above CG configuration information, embodiments of the present disclosure also provide a data transmission method by the method shown in Figure 2. As shown in Figure 4, Figure 4 is a fourth schematic flowchart of the data transmission method provided by embodiments of the present disclosure. In the method shown in Figure 4, step S102 above is refined into the following steps, namely steps S1022 to S1023.

[0129] In step S1022, if the received paging message contains a specified paging record for the target terminal and the specified paging record does not contain a non-conflict access preamble, the connection resume request is sent to the target network device using a conflict access method.

[0130] In step S1023, if the received paging message contains a specified paging record for the target terminal and the specified paging record contains a conflict-free access preamble, the connection resume request is sent to the target network device using a conflict-free access method.

[0131] In the embodiments of this disclosure, since the target terminal does not store the above-mentioned CG configuration information, the target terminal cannot initiate small data transmission in the inactive state process using the CG configured grant method. In this case, the target terminal can initiate small data transmission in the inactive state process using the random access method.

[0132] When a received paging message contains a specified paging record on the target terminal, the specified paging record may or may not contain the above-mentioned non-conflict access preamble.

[0133] In some embodiments, if the designated paging record does not contain the non-conflict access preamble, the target terminal performs step S1022 above. That is, the target terminal can initiate small data transmission in an inactive state process using a conflict access method.

[0134] In another embodiment, when the designated paging record includes the no-conflict access preamble, the target terminal performs step S1023, i.e., based on the no-conflict access preamble in the designated paging record, to initiate small data transmission in the inactive state process using a no-conflict access method. Specifically, the target terminal can send the no-conflict access preamble to the target network device. The target network device feeds back a random access response message to the target terminal in response to the received no-conflict access preamble. The target terminal then receives the random access response message. The target terminal can obtain uplink synchronization in accordance with the timing synchronization information of the random access response message and send a connection resume request in accordance with the uplink resources allocated by the target network device.

[0135] In steps S1022 and S1023 above, SDT based on Random Access Channel (RACH) may be configured for the terminal's initial BWP, and SDT based on RACH may also be configured for the terminal's NUL carrier and SUL carrier.

[0136] Regarding the RACH-based SDT process described above, the target terminal receives the 2-step RACH resources and / or 4-step RACH resources sent by the target network device for SDT transmission.

[0137] In embodiments of this disclosure, steps S1022 and S1023 are performed depending on whether the designated paging record contains a non-conflicting access preamble, respectively. Herein, performing steps S1022 and S1023 is not particularly limited.

[0138] If the target terminal does not store CG configuration information as a result of steps S1022 and S1023 above, for example, when the target terminal moves from one specific RAN cell to another, small data transmission in the inactive state process can be initiated using different conflict access methods and conflict-free access methods depending on the presence or absence of a conflict-free access preamble in the specified paging record, thereby effectively improving the adaptability of small data transmission in the inactive state.

[0139] In some embodiments, the priority of the above-mentioned small data transmission in an inactive state initiated based on CG configuration information may be higher than the priority of the above-mentioned small data transmission in an inactive state initiated by a random access method. That is, if the target terminal has the above-mentioned CG configuration information stored, the target terminal may preferentially use the method shown in step S1021 above to send a connection resume request to the target network device, regardless of whether the above-mentioned designated paging record contains the above-mentioned non-conflict access preamble.

[0140] In some embodiments, before a connection resumption request is sent to the target network device, it is determined whether the target terminal currently meets the preset connection initiation conditions.

[0141] Here, the preset connection initiation conditions include receiving a mobile-terminated small data transmission instruction, or receiving a mobile-terminated small data transmission instruction and the downlink reference signal received power (RSRP) being greater than a preset threshold.

[0142] In some embodiments, the above preset connection initiation conditions are when a mobile-terminated small data transmission instruction is received, or when a mobile-terminated small data transmission instruction is received and the lower layers below the RRC layer are Mobile Terminate This indicates that the trigger condition for sending small data has been met.

[0143] In some embodiments, if another preset connection initiation condition is met, another connection resume request is sent so that the target terminal sends uplink data packets to the target network device after the connection corresponding to this other connection resume request has been resumed. The other preset connection initiation condition is a mobile... Originated The data volume of a wireless bearer configured for small data transmission is below the preset data volume threshold, or the data volume of a wireless bearer configured for mobile-originated small data transmission is below the preset data volume threshold, and the uplink small data transmission resource is enabled.

[0144] In some embodiments, the above alternative preset connection initiation conditions also include a higher layer above the Radio Resource Control (RRC) layer requesting the resumption of the RRC connection, a System Information Block Type 1 (SIB1) containing a common configuration for small data transmissions, a small data transmission configuration being configured, all uplink small data being mapped to the radio bearers of the small data transmission configuration, and a lower layer below the RRC layer, Mobile-Originated. This can also be expressed as indicating that the trigger condition for sending small data has been met.

[0145] Here, the above-mentioned preset connection initiation conditions and other preset connection initiation conditions are not particularly limited. The above-mentioned preset data volume threshold and preset threshold may be set according to the user's needs, the capacity of the wireless network, etc., and are not particularly limited here.

[0146] In some embodiments, the embodiments of the present disclosure also provide a data transmission method according to the method shown in Figure 1. As shown in Figure 5, Figure 5 is a fifth schematic flowchart of the data transmission method provided by the embodiments of the present disclosure. This method includes the following steps:

[0147] In step S501, when the current state of the target terminal is inactive, a paging message issued by the target network device is received according to a first time period.

[0148] Step S501 described above is the same as step S101 described above.

[0149] In step S502, when the received paging message contains the target terminal's designated paging record, it is determined whether the target terminal currently meets the preset connection initiation conditions. The preset connection initiation conditions are: a mobile-terminated small data transmission instruction is received; or a mobile-terminated small data transmission instruction is received and the downlink RSRP is greater than a preset threshold. In this step, when the paging message received by the target terminal contains the target terminal's own designated paging record, the target terminal can determine whether the target terminal itself meets the preset connection initiation conditions, and if it does, step S503 is performed.

[0150] The lower layers below the RRC layer may be a Medium Access Control (MAC) layer, a Physical (PHY) layer, etc. The upper layers above the RRC layer may be any layer above the RRC layer. Here, the above upper and lower layers are not particularly limited.

[0151] In step S503, when the target terminal meets the preset connection initiation conditions, a connection resume request is sent to the target network device, which then sends downlink small data packets to the target terminal based on the received connection resume request. The specified paging record includes a mobile-terminated small data transmission instruction, and the reason for connection resume in the connection resume request is mobile-terminated small data transmission.

[0152] In this step, when the target terminal satisfies the preset connection initiation conditions described above, the target terminal can send a connection resume request to the target network device. The sending of the connection resume request in step S102 above may be specifically referenced and will not be described in detail here.

[0153] In some embodiments, if the target terminal does not meet the above-mentioned preset connection initiation conditions, the target terminal does not need to perform any processing. That is, the above step of sending a connection resumption request is not performed.

[0154] By determining the above preset connection initiation conditions, it is possible to ensure that the target terminal satisfies the conditions for initiating small data transmission in an inactive state, thereby ensuring the success of the small data transmission process in an inactive state between the target terminal and the target network device.

[0155] In step S504, the downlink small data packet sent by the target network device is received.

[0156] Step S504 described above is the same as step S103 described above.

[0157] In some embodiments, the embodiments of the present disclosure also provide a data transmission method according to the method shown in Figure 5. As shown in Figure 6, Figure 6 is a sixth schematic flowchart of the data transmission method provided by the embodiments of the present disclosure. This method includes the following steps:

[0158] In step S601, when the current state of the target terminal is inactive, the paging message sent by the target network device is received according to a first time period.

[0159] In step S602, if the received paging message contains the specified paging record for the target terminal, it is determined whether the target terminal currently meets the preset connection initiation conditions. 。

[0160] In step S603, when the target terminal meets the preset connection initiation conditions, a connection resume request is sent to the target network device, which then sends downlink small data packets to the target terminal based on the received connection resume request. The specified paging record includes a mobile-terminated small data transmission instruction, and the connection resume reason in the connection resume request is mobile-terminated small data transmission.

[0161] Steps S601 to S603 above are the same as steps S501 to S503 above.

[0162] In step S604, when the target terminal meets the preset connection start conditions, the inactive state restart process is initiated. keru Small data transmission Whether it was a failure or not of SurveillanceA timer is started to perform the action.

[0163] Both steps S603 and S604 described above are performed when the target terminal satisfies the preset connection initiation conditions. Here, the order in which steps S603 and S604 are performed is not particularly limited.

[0164] In step S605, the downlink small data packet sent by the target network device is received.

[0165] Step S605 described above is the same as step S504 described above.

[0166] In step S606, if the target terminal does not meet the preset connection initiation conditions, connection A timer is started to monitor the restart process, and a timeout instruction is sent to the MAC entity. The timeout instruction is set in the CG Timing Advance Timer in the CG configuration information for small data transmission. Stop It is used to indicate something.

[0167] By steps S604 and S606 described above, the target terminal can, when the preset connection initiation conditions are met, start a timer to detect the inactive transmission restart process to ensure that no timeout occurs during the inactive transmission restart process, and when the preset connection initiation conditions are not met, start a timer to monitor the inactive restart process to ensure that the inactive restart process is successful.

[0168] In some embodiments, the connection resumption request mentioned above refers to either the first connection resumption request or the second connection resumption request.

[0169] The first and second connection resumption requests described above each include a resumption identifier, a resumption integrity check code, and a reason for resuming the connection.

[0170] The reactivation identifier for the first connection reactivation request is the fully inactive terminal identification information stored by the target terminal, and the reactivation identifier for the second connection reactivation request is the abbreviated inactive terminal identification information stored by the target terminal. The reactivation integrity check code is an identification information authentication token used for terminal identification information authentication at the base station. The fully inactive terminal identification information and the abbreviated inactive terminal identification information are wireless network temporary identifier values ​​of an inactive terminal, and are used by the target network to find the anchor point before the terminal entered the inactive state and the access layer context information stored by the anchor point. The fully inactive terminal identification information and the abbreviated inactive terminal identification information have different sizes.

[0171] In some embodiments, the embodiments of the present disclosure also provide a connection resume request sending method according to the method shown in Figure 1. As shown in Figure 7, Figure 7 is a schematic flowchart of the connection resume request sending method provided by the embodiments of the present disclosure. This method includes the following steps:

[0172] In step S701, if the SIB1 sent by the base station indicates that the reactivation request will use a full reactivation identifier, the first reactivation request is selected as the reactivation request; or if the received SIB1 does not indicate that it will use a full reactivation identifier, the second reactivation request is selected as the reactivation request.

[0173] In this step, the base station of the core network can send SIB1 to the target terminal. The target terminal receives the SIB1. SIB1 contains information indicating a resumption identifier used for connection resumption requests.

[0174] In some embodiments, if the received SIB1 indicates that the resumption identifier in the connection resumption request uses a complete resumption identifier, the target terminal can determine that the resumption identifier in the connection resumption request is the complete inactive terminal identification information stored by the target terminal. In this case, the target terminal can select the first connection resumption request as the connection resumption request.

[0175] In another embodiment, if the received SIB1 does not indicate that the resumption identifier in the connection resumption request uses a full resumption identifier, the target terminal can determine that the resumption identifier in the connection resumption request is the shortened inactive terminal identification information (recorded as Short I-RNTI) stored by the target terminal. In this case, the target terminal can select the second connection resumption request as the connection resumption request.

[0176] In step S702, preset security information is restored from stored access layer context information. The preset security information includes RRC configuration, ROHC status, stored mapping relationships between QoS flows and DRB, base station route key, and integrity protection key.

[0177] In embodiments of this disclosure, the access layer context information described above can be stored in an anchor point. The anchor point reserves the UE context information and the NG connection between the UE-related Access and Mobility Management Function (AMF) and User Plane Function (UPF) for the geodesic network base station (gNB). The NG is a logical interface between the radio access network and the core network.

[0178] In step S703, the PDCP entity is reconstructed for SIB1.

[0179] In step S704, SIB1 is restored.

[0180] In step S705, for each radio bearer configured for mobile-terminated small data transmission, the primary cell group and configuration associated with the RLC bearer of the PDCP configuration are restored from the access layer context information, and the PDCP entity is reconstructed for this radio bearer.

[0181] In step S706, all radio bearers configured for mobile-terminated small data transmission are restarted.

[0182] In step S707, a connection resumption request is sent to the target network device.

[0183] Steps S701 to S707 described above are refinements of the step in step S102 described above, which involves sending a connection resumption request to the target network device.

[0184] In some embodiments, the embodiments of the present disclosure also provide a data transmission method according to the method shown in Figure 1. As shown in Figure 8, Figure 8 is a seventh schematic flowchart of the data transmission method provided by the embodiments of the present disclosure. This method includes the following steps:

[0185] In step S801, when the target terminal's current state is connected, a first release message issued by the target network device is received. The first release message includes suspension configuration information indicating that the terminal is to perform an inactive state configuration.

[0186] In embodiments of this disclosure, in addition to being in an inactive state, the target terminal may also be connected and idle. When the target terminal is connected, the target network device may send an RRC release message (recorded as a first release message) to the target terminal. The target terminal then receives the first release message.

[0187] In some embodiments, the first release message described above may include suspension configuration information. The suspension configuration information is used to indicate that the terminal is performing an inactive state configuration.

[0188] The above suspension configuration information may include fully inactive terminal identification information (i.e., Full I-RNTI above), shortened inactive terminal identification information (i.e., Short I-RNTI above), radio paging period, radio (RAN) notification area information, timer, next-hop chaining count value, and mobile-terminated small data transmission configuration information.

[0189] In some embodiments, the fully inactive terminal identification information and the abbreviated inactive terminal identification information are temporary wireless network identifier values ​​of an inactive terminal, and are used by the target network to find the anchor point node before the terminal entered the inactive state and the access layer context information stored by that anchor point node. The fully inactive terminal identification information and the abbreviated inactive terminal identification information have different sizes. For example, the fully inactive terminal identification information may be 40 bits in size, and the abbreviated inactive terminal identification information may be 24 bits in size. Here, the sizes of the fully inactive terminal identification information and the abbreviated inactive terminal identification information are not particularly limited.

[0190] The above wireless paging period is the RAN paging period configured by the RAN-side node (e.g., base station) for an inactive terminal. The wireless paging period can be 32 wireless frames, 64 wireless frames, 128 wireless frames, 256 wireless frames, etc. Here, the wireless paging period is not particularly limited.

[0191] Wireless (RAN) notification area information includes a list of cells configured as a RAN area and the RAN area code or RA It may include a code (i.e., a wireless area configuration list).

[0192] The timer described above is used to trigger a periodic RNAU process on the terminal.

[0193] The above next-hop chaining count value is used to calculate the security key after the connection is re-established.

[0194] The above configuration information for mobile-terminated small data transmission is: Mobile Terminate DRB list for small data transmission or Mobile Terminate Includes at least one of the SRB2 instructions for small data transmission. Mobile Terminate The DRB list for small data transmissions indicates the DRB identifiers for the small data transmission configuration. Mobile Terminate The SRB2 instruction for small data transmission is used to indicate the presence or absence of an SRB2 in the terminal's small data transmission configuration. SRB stands for Signaling Radio Bearer. For example, the configuration information for mobile-terminated small data transmission is: Mobile Terminate DRB list for small data transmission or Mobile Terminate Includes SRB2 instructions for small data transmission. In another example, configuration information for mobile-terminated small data transmission is: Mobile Terminate DRB list for small data transmission and Mobile Terminate Includes SRB2 instructions for small data transmission.

[0195] Inactive state Mobile TerminateIn the above DRB list for small data transmission, if the sequence size is 0, the target terminal can determine that the network does not have a DRB configured for small data transmission.

[0196] In some embodiments, the above configuration information for mobile-terminated small data transmission may further include CG configuration information. Success The report includes CG SSB RSRP thresholds, CG timing advance timers, CG timing advance verification configurations, and CG RSRP variation thresholds.

[0197] The above CG SSB RSRP thresholds enable small data transmission based on CG resources. SSB (Synchronization Signal and PBCH block) This is the RSRP threshold selected by [the specified method]. The above CG Timing Advance Timer is used for timing synchronization of small data transmissions. The CG Timing Advance Verification configuration is used for TA verification configuration based on RSRP. The above CG RSRP Variation Threshold is the RSRP threshold for TA verification of small data transmissions.

[0198] In some embodiments, when the above-mentioned CG timing advanced verification configuration is not configured in the above-mentioned CG configuration information, the target terminal does not perform the TA verification process based on RSRP.

[0199] In embodiments of this disclosure, with respect to the suspension configuration information described above, when the network redirects the terminal to a carrier frequency between radio access technologies (RATs), or when configuring a Dual Active Protocol Stack (DAPS) bearer for the terminal, the network does not configure the suspension configuration information for the terminal. That is, the first release message described above does not include the suspension configuration information described above.

[0200] In some embodiments, the target terminal can store the suspension configuration information after receiving it. For example, the target terminal can store the Full I-RNTI and Short I-RNTI. Depending on the stored Full I-RNTI and Short I-RNTI, the designated paging record is queried, and a first connection resumption request / second connection resumption request is sent, and so on.

[0201] In step S802, the current state is switched to an inactive state based on the suspension configuration information.

[0202] In the embodiments of this disclosure, after receiving the first release message described above, the target terminal performs the following steps based on the first release message to switch the current state of the target terminal from connected state to inactive state.

[0203] In the first step, the MAC is reset, and the default MAC cell group configuration is released.

[0204] In the second step, the suspension configuration information is applied.

[0205] In the third step, when the CG configuration information is included in the suspension configuration information, Mobile Terminate Each DRB in the DRB list for small data transmission and Mobile Terminate SRB2 instruction for small data transmission SRB2 shown in but, Mobile Terminate The DRB and SRB2 are determined during the small data transmission process; the RLC entity is rebuilt for each RLC bearer in the target terminal configuration; the PDCP entity is triggered to perform the SDU discard process for the restarted SRB2 and SRB1; the small data transmission CG resource is configured for the MAC entity and the CG timing advance timer is started.

[0206] In the fourth step, the current access layer root key (KgNB) and RRC signaling integrity protection key (KRRCint), ROHC status, stored mapping rules between QoS flows and data resource bearers (DRBs), C-RNTI used by the source PCell, cell identifier, physical cell identifier of the source PCell, SpCell common configuration in the NR PSCell synchronous reconfiguration message, PCell synchronous reconfiguration message parameters, NR PSCell synchronous reconfiguration message parameters, E-UTRA PSCell SCG mobility control information, EN-DC PSCell configuration, and all other configuration parameters except the service cell common configuration SIB are stored in the access layer context information of the inactive terminal.

[0207] The SpCell mentioned above is a set of Pcell and PSCell, and can be expressed as SpCell = Pcell + PSCell. EN-DC is E-UTRA NR dual connectivity between a Master Cell Group (MCG) using Universal Terrestrial Radio Access (E-UTRA) and an SCG using New Radio (NR).

[0208] In the fourth step described above, the SpCell common configuration included in the NR PSCell synchronous reconfiguration message, as well as the parameters in the PCell synchronous reconfiguration message, the parameters in the NR PSCell synchronous reconfiguration message, and other configuration parameters other than the SCG mobility control information of the E-UTRA PSCell are all processed according to the configuration conditions in the CG configuration described above, but this will not be explained in detail here.

[0209] In the fifth step, all SRBs except SRB0 and DRB are suspended.

[0210] In the sixth step, all lower layers of the DRB are instructed to implement PDCP suspension, and the lower layers are placed below the RRC layer.

[0211] In the seventh step, the inactive state is switched off and the cell is reselected.

[0212] In the seventh step described above, the target terminal can perform cell reselection according to the relevant standard, for example, the steps in TS38.304. The cell reselection process will not be described in detail here.

[0213] Steps S801 to S802 described above allow the target terminal to switch its current state from connected to inactive in response to the first release message received, thereby facilitating the target terminal to quickly transition from connected to inactive, and also facilitating the process of small data transmission in the inactive state when the target terminal's specified paging record is received later, thereby reducing signaling overhead and delay consumption during the data transmission process.

[0214] In step S803, a system message broadcast by the target network device is received. The system message includes at least one of the following: downlink transmit frequency information, initial downlink BWP, BCCH configuration information, or PCCH configuration information.

[0215] For example, a system message may include downlink transmission frequency information, initial downlink BWP, BCCH configuration information, or PCCH configuration information. In another example, a system message may include downlink transmission frequency information and initial downlink BWP, or BCCH configuration information and PCCH configuration information, or downlink transmission frequency information and BCCH configuration information, or downlink transmission frequency information and PCCH configuration information, or initial downlink BWP and BCCH configuration information, or initial downlink BWP and PCCH configuration information. In yet another example, a system message may include downlink transmission frequency information and initial downlink BWP and BCCH configuration information, or initial downlink BWP, BCCH configuration information, and PCCH configuration information, or downlink transmission frequency information, BCCH configuration information, and PCCH configuration information, or downlink transmission frequency information, initial downlink BWP, and PCCH configuration information. In yet another example, a system message may include downlink transmission frequency information, initial downlink BWP, BCCH configuration information, and PCCH configuration information.

[0216] In this step, the target network device can broadcast a system message within its corresponding network coverage. Each terminal within that network coverage can then receive the system message; that is, the target terminal can receive the system message.

[0217] The above system message may include common downlink configuration information for downlink small data transmission and reception. This common downlink configuration information may include downlink transmission frequency information, initial downlink BWP, BCCH configuration information, and PCCH configuration information.

[0218] The initial downlink BWP described above is the initial downlink BWP configuration of the primary cell (i.e., the PCell described above). The BCCH configuration information described above is the configuration for modifying the passing period of system messages. The PDCCH configuration information includes the default paging period, paging frame number and configuration, the number of paging occasions, and the first PDCCH monitoring occasion.

[0219] The default paging period is the default paging period broadcast in system messages. The paging frame number and configuration are used to derive the total number of paging frames and the paging frame offset. The number of paging occasions is used to indicate the number of paging occasions within each paging frame. A paging occasion is a group of PDCCH monitoring occasions consisting of multiple time slots for sending paging control information. The first PDCCH monitoring occasion is the first PDCCH monitoring occasion that indicates monitoring the paging occasion of a paging frame.

[0220] In the embodiments of this disclosure, the order in which steps S801 to S803 are performed is not particularly limited.

[0221] In step S804, the smaller of the wireless paging period and the default paging period is determined as the first time period for receiving paging messages when the target terminal is inactive. The wireless paging period is the RAN paging period configured by the Radio Access Network (RAN) side node for the inactive terminal.

[0222] In this step, the target terminal obtains the smaller of the default paging period and the wireless paging period, depending on the default paging period in the downlink common configuration information included in the system message and the wireless paging period in the suspension configuration information included in the first release message, and can determine this paging period as the time period for the target terminal to receive the paging message (i.e., the first time period). That is, if the default paging period is less than the wireless paging period, the default paging period is determined as the first time period, and if the default paging period exceeds the wireless paging period, the wireless paging period is determined as the first time period.

[0223] By steps S803 to S804 described above, the target terminal can determine the time period for receiving paging messages on its own, depending on the paging period included in the system message and the first release message, thereby effectively ensuring that the target terminal can receive paging messages issued by the target network device as much as possible.

[0224] In step S805, when the current state of the target terminal is inactive, a paging message issued by the target network device is received according to a first time period.

[0225] In some embodiments, the first time period described above is the smaller of the wireless paging period in the suspension configuration information and the default paging period in the downlink common configuration information.

[0226] In step S806, if the received paging message contains a specified paging record of the target terminal, a connection resume request is sent to the target network device, which then sends downlink small data packets to the target terminal based on the received connection resume request. The specified paging record contains a mobile-terminated small data transmission instruction, and the reason for connection resume in the connection resume request is mobile-terminated small data transmission.

[0227] In step S807, the downlink small data packet sent by the target network device is received.

[0228] Steps S805 to S807 above are the same as steps S101 to S103 above.

[0229] In some embodiments, the above connection resumption request may also include an uplink small data packet. When the above connection resumption request includes an uplink small data packet, embodiments of the present disclosure also provide a data transmission method according to the method shown in Figure 1. As shown in Figure 9, Figure 9 is an eighth schematic flowchart of the data transmission method provided by embodiments of the present disclosure. This method includes the following steps:

[0230] In step S901, when the current state of the target terminal is inactive, a paging message issued by the target network device is received according to a first time period.

[0231] Step S901 described above is the same as step S101 described above.

[0232] In step S902, if the received paging message contains a designated paging record for the target terminal, a resume request is sent to the target network device, which then sends downlink small data packets to the target terminal based on the received resume request. The designated paging record contains a mobile-terminated small data transmission instruction, and the reason for resume in the resume request is mobile-terminated small data transmission.

[0233] In step S902 above, when the target terminal sends a connection resume request to the target network device, the connection resume request may further include an uplink small data packet. The uplink small data packet is either uplink data or a data packet corresponding to a subpacket obtained by dividing the uplink data. For uplink small data packets, refer to the description of downlink small data packets above, which will not be specifically described here.

[0234] The data volume of the above uplink small data packets may be below the second data volume threshold.

[0235] In embodiments of the present disclosure, when the target network device receives the connection resumption request including the uplink small data packet, in addition to sending the downlink small data packet to the target terminal, the target network device may also generate corresponding feedback information for the uplink small data packet in the connection resumption request and send that feedback information to the target terminal, i.e., send the downlink small data packet to the target terminal together with the feedback information. The generation of the feedback information will not be described in detail here.

[0236] In step S903, the downlink small data packets sent by the target network device and the feedback information sent by the target network device for the uplink small data packets are received.

[0237] In this step, the target network device sends the downlink small data packets to the target terminal, as well as feedback information for the uplink small data packets, so the target terminal receives the downlink small data packets and the feedback information.

[0238] In some embodiments, when the uplink small data packets described above are subpackets corresponding to uplink data, i.e., there are still some uplink small data packets at the target terminal that have not been sent to the target network device. When the target terminal receives feedback information sent by the target network device, the target terminal can send the remaining unsent uplink small data packets to the target network device. The target network device receives the uplink small data packets sent by the target terminal and obtains all the uplink data sent by the target terminal to the target network device.

[0239] In the above embodiment, since there may be two or more remaining untransmitted uplink small data packets, the target terminal transmits only one uplink small data packet in each transmission process during the mobile-originated small data transmission process. The data volume of each uplink small data packet is less than or equal to the second data volume threshold described above.

[0240] The second data volume threshold described above may be greater than or less than the first data volume threshold described above, and may be specifically set by referring to the method for setting the first data volume threshold described above. Here, the second data volume threshold is not particularly limited.

[0241] During the uplink small data transmission process described above, uplink small data packets can be transmitted using small data transmission resources configured by CG configuration information assigned by the target network device, or using uplink time-frequency resources temporarily scheduled by the target network device.

[0242] By carrying the above-mentioned uplink small data packets in the connection resumption request, an inactive uplink data transmission process is realized, avoiding the signaling overhead and latency consumption caused by switching from an inactive state to a connected state, improving the transmission efficiency of uplink small data packets, saving signaling overhead for uplink small data packets, and thereby effectively reducing signaling overhead and latency consumption in the data transmission process.

[0243] In some embodiments, the embodiments of the present disclosure also provide a data transmission method according to the method shown in Figure 1. As shown in Figure 10, Figure 10 is a ninth schematic flowchart of the data transmission method provided by the embodiments of the present disclosure. This method includes the following steps:

[0244] In step S1001, when the current state of the target terminal is inactive, a paging message issued by the target network device is received according to a first time period.

[0245] In step S1002, if the received paging message contains a specified paging record of the target terminal, a connection resume request is sent to the target network device, which then sends downlink small data packets to the target terminal based on the received connection resume request. The specified paging record contains a mobile-terminated small data transmission instruction, and the reason for connection resume in the connection resume request is mobile-terminated small data transmission.

[0246] In step S1003, the downlink small data packet sent by the target network device is received.

[0247] Steps S1001 to S1003 above are the same as steps S101 to S103 above.

[0248] In step S1004, a second release message is received, which was sent by the target network device when the transmission of the downlink small data packet was complete. The second release message contains instruction information indicating a state switch.

[0249] In this step, when the target network device has completed sending the downlink small data packets described above, that is, after sending all downlink small data packets corresponding to the downlink data described above to the target terminal, the target network device can send an RRC release message (recorded as a second release message) to the target terminal. At this point, the target terminal receives the second release message.

[0250] In embodiments of this disclosure, the instruction information in the second release message may be used to indicate that the terminal's current state is to be switched to an inactive state, or, like the suspension configuration information, to indicate that the terminal's current state is to be switched to an idle state. Depending on another state that the target terminal is required to switch to, the instruction information in the second release message may also change. Here, the instruction information in the second release message is not particularly limited.

[0251] In step S1005, the current state is switched to an inactive state or an idle state based on the instruction information.

[0252] In this step, after receiving the second release message described above, the target terminal can perform a state switch based on the instructions in the second release message. For example, the current state can be switched to an inactive or idle state. The state switch process of the target terminal will not be described in detail here.

[0253] In embodiments of this disclosure, after the target terminal is switched to an inactive or idle state in response to the instruction information of the second release message, the target terminal and target network device are no longer able to perform the small data transmission described above in the inactive state. That is, the uplink small data packet transmission and downlink small data packet transmission described above are no longer performed.

[0254] By sending the second release message described above, the RRC connection between the target terminal and the target network device can be disconnected in a timely manner when small data transmission in an inactive state is complete, thereby freeing up system resources.

[0255] In some embodiments, when there are two or more of the downlink small data packets described above, the target network device may send the last downlink small data packet among the downlink small data packets to the target terminal along with the second release message described above, in order to further reduce signaling overhead and latency consumption during the data transmission process.

[0256] In the above embodiment, the second release message is sent after the transmission of the last downlink small data packet corresponding to the downlink data. Furthermore, when the amount of uplink data is greater than that of downlink data, i.e., when the transmission of all downlink small data packets has been completed but the transmission of all uplink small data packets has not been completed, the target network device may send the second release message to the target terminal after receiving the last uplink small data packet. Here, the time for sending the second release message is not particularly limited.

[0257] Based on the same inventive concept, the present disclosure also provides a data transmission method according to the data transmission method provided by embodiments of the present disclosure. As shown in Figure 11, Figure 11 is a schematic flowchart of a tenth data transmission method provided by embodiments of the present disclosure. This method is applied to a target network device and includes, in particular, the following steps.

[0258] In step S1101, a paging message is sent to the target terminal, whose current state is inactive, according to a second time period.

[0259] In this step, the target network device may send paging messages to connected or inactive terminals within the target network device's network coverage, depending on the second time period. At this time, terminals within the target network device's network coverage receive the paging messages. That is, the target terminals receive the paging messages.

[0260] In embodiments of this disclosure, the above-mentioned paging message can be sent in the form of multicast / broadcast or the like. The method of sending the above-mentioned paging message is not particularly limited.

[0261] In some embodiments, the above-described paging message may include a paging record list. The paging record list is a list for recording the terminal being paged, and the paging record list includes at least one paging record.

[0262] In some embodiments, the above-described paging record includes at least one of the following: terminal identification information of the paged terminal, access type, or mobile-terminated small data transmission instruction.

[0263] For example, a paging record may include the terminal identification information, access type, or mobile-terminated small data transmission instruction of the paged terminal. In another example, a paging record may include the terminal identification information and access type of the paged terminal, or the terminal identification information and mobile-terminated small data transmission instruction of the paged terminal, or the access type and mobile-terminated small data transmission instruction. In yet another example, a paging record may include the terminal identification information, access type, and mobile-terminated small data transmission instruction of the paged terminal.

[0264] The terminal identification information includes a NAS ID assigned to the terminal by the NAS for core network paging and complete inactive state terminal identification information for RAN paging. The above access type is used to indicate whether a paging message is initiated by a PDU session not accessed by 3GPP. The mobile terminated small data transmission indication is used to indicate that a paging message is used to trigger mobile terminated small data transmission.

[0265] In some embodiments, the above paging record may further include a contention-free access preamble indicating to the terminal to initiate a contention-free random access.

[0266] In step S1102, a connection resume request sent by the target terminal is received. The connection resume request is sent by the target terminal when a paging message including the target terminal's designated paging record is received. The designated paging record includes a mobile terminated small data transmission indication. The reason for connection resume in the connection resume request is mobile terminated small data transmission.

[0267] In this step, after the target network device sends the above paging message to the target terminal, when the paging message includes the target terminal's designated paging record, the target terminal sends a connection resume request to the target network device with the reason for connection resume being mobile terminated small data transmission. The target network device receives the connection resume request.

[0268] The above designated paging record includes a mobile terminated small data transmission indication. For the description of the designated paging record, reference may be made to the above description and will not be described in particular detail here.

[0269] In step S1103, a downlink small data packet is sent to the target terminal based on the connection resumption request, and thereby the target terminal receives the downlink small data packet.

[0270] In this step, after the target network device receives the connection resumption request sent by the target terminal, since the connection resumption reason in the connection resumption request is mobile terminated small data transmission, the target network device can obtain a downlink small data packet based on the connection resumption reason and send this downlink small data packet to the target terminal. For the description of the downlink small data packet, reference can be made to the above description, and it will not be described in detail here.

[0271] In some embodiments, the above connection resumption request may be a first connection resumption request or a second connection resumption request. The first connection resumption request is sent by the target terminal when the SIB1 sent by the base station indicates that the connection resumption request uses a full resumption identifier, and the second connection resumption request is sent by the target terminal when the SIB1 sent by the base station does not indicate that the connection resumption request uses a full resumption identifier.

[0272] The above first connection resumption request and second connection resumption request each include a resumption identifier, a resumption integrity check code, and a connection resumption reason.

[0273] The reactivation identifier for the first connection reactivation request is the fully inactive terminal identification information stored by the target terminal, and the reactivation identifier for the second connection reactivation request is the abbreviated inactive terminal identification information stored by the target terminal. The fully inactive terminal identification information and the abbreviated inactive terminal identification information are temporary wireless network identifier values ​​of the inactive terminal, and are used by the target network to find the anchor point before the terminal entered the inactive state and the access layer context information stored by the anchor point. The fully inactive terminal identification information and the abbreviated inactive terminal identification information have different sizes. The reactivation integrity check code is an identification information authentication token for terminal identification information authentication at the base station.

[0274] In the first and second connection resume requests described above, the resume identifier is a UE identifier for facilitating UE context information retrieval in the gNB, for example, resumeIdentify in RRCResumeRequest1 of the relevant standard TS38.331. The resume integrity check code described above is a bit string and is an authentication token for UE authentication in the gNB (for example, resume MAC-I in the relevant standard TS38.331). The resume reason described above is a reason for resuming provided by the upper layer or RRC and added in the initial connection resume request. When the UE uses an unknown reason value (for example, MT-SDT in the embodiments of this disclosure), the gNB does not reject the first connection resume request in accordance with the relevant standard, such as resumeCause in TS38.331.

[0275] As shown in Figure 11, when the target terminal is in an inactive state, a reactivation request may be sent to the target network device if the target terminal receives a paging message containing a designated paging record for the target terminal itself issued by the target network device, thereby triggering the small data transmission process between the target terminal and the target network device when the terminal is in an inactive state. In this case, the target network device can send downlink small data packets to the target terminal based on the received reactivation request, and the target terminal also receives the downlink small data packets, thereby enabling the downlink small data packet transmission process for the inactive terminal.

[0276] Furthermore, compared to related technologies in which an inactive terminal must switch to a connected state for data transmission, embodiments of the present disclosure introduce a new terminal access type, namely mobile-terminated small data transmission, through a mobile-terminated small data transmission instruction in a designated paging record, so that the terminal can receive downlink small data packets sent by a target network device while in an inactive state. This avoids the signaling overhead and latency consumption resulting from switching from an inactive state to a connected state, improves the transmission efficiency of downlink small data packets, saves signaling overhead for downlink small data packets, and thus effectively reduces signaling overhead and latency consumption in the data transmission process.

[0277] In some embodiments, embodiments of the present disclosure also provide a data transmission method according to the method shown in Figure 11. As shown in Figure 12, Figure 12 is a schematic flowchart of an eleventh data transmission method provided by embodiments of the present disclosure. This method includes the following steps:

[0278] In step S1201, a first release message is issued to the terminal. The first release message includes suspension configuration information indicating that the terminal should perform an inactive state configuration, thereby causing the target terminal to switch its current state to an inactive state based on that suspension configuration information.

[0279] In this step, the target network device can send an RRC release message (i.e., the first release message described above) to a connected target terminal. The first release message includes suspension configuration information indicating that the terminal should perform an inactive configuration. After receiving the first release message, the target terminal can switch its state according to the suspension configuration information in the first release message, i.e., switch its current state from connected to inactive.

[0280] The above suspension configuration information includes fully inactive terminal identification information, shortened inactive terminal identification information, wireless paging period, wireless notification area information, timer, next-hop chaining count value, and mobile terminated small data transmission configuration information.

[0281] The fully inactive terminal identifier and abbreviated inactive terminal identifier described above are temporary wireless network identifier values ​​for inactive terminals. They are used by the target network to locate the anchor point node before the terminal entered the inactive state, and the access layer context information stored by that anchor point node. The fully inactive terminal identifier and abbreviated inactive terminal identifier have different sizes.

[0282] The wireless paging period refers to the RAN paging period configured by the RAN-side node for inactive terminals.

[0283] The wireless notification area information includes a cell list and a wireless area configuration list. The cell list is a list of cells configured in the RAN area as and the wireless area configuration list includes a RAN area code or a RA code of the RAN area.

[0284] The timer is used to trigger a periodic RNAU process in the terminal.

[0285] The next-hop chaining count value is used to calculate a security key after the connection is resumed.

[0286] The configuration information of mobile-terminated small data transmission Mobile Terminate includes at least one of a DRB list for small data transmission or Mobile Terminate an SRB2 indication for small data transmission. Mobile Terminate The DRB list for small data transmission indicates the DRB identifiers of the small data transmission configuration, Mobile Terminate and the SRB2 indication for small data transmission is used to indicate the presence or absence of SRB2 in the small data transmission configuration of the terminal. For example, the configuration information of mobile-terminated small data transmission Mobile Terminate includes a DRB list for small data transmission or Mobile Terminate an SRB2 indication for small data transmission. In another example, the configuration information of mobile-terminated small data transmission Mobile Terminate includes a DRB list for small data transmission and Mobile Terminate an SRB2 indication for small data transmission.

[0287] In some embodiments, the above configuration information of mobile-terminated small data transmission may further include CG configuration information. The CG Success configuration information includes a CG SSB RSRP threshold, a CG timing advance timer, a CG timing advance verification configuration, and a CG RSRP variation threshold.

[0288] The CG SSB RSRP threshold is the RSRP threshold selected by the SSB performing small data transmissions based on CG resources. The CG Timing Advance Timer is used for timing synchronization of small data transmissions. The CG Timing Advance Verification configuration is used for configuring TA verification based on RSRP. The CG RSRP Variation Threshold is the RSRP threshold for TA verification of small data transmissions.

[0289] Step S1201 described above allows the target terminal to switch its current state from connected to inactive in response to the first release message issued by the target network device, thereby returning the target terminal to the connected state. From inactive state This facilitates quick input and also streamlines the process of sending small data in an inactive state when the specified paging record of the target terminal is received later, thereby reducing signaling overhead and latency consumption during the data transmission process.

[0290] In step S1202, a system message is broadcast. The system message includes at least one of the following: downlink transmit frequency information, initial downlink BWP, BCCH configuration information, and PCCH configuration information.

[0291] For example, a system message may include downlink transmission frequency information, initial downlink BWP, BCCH configuration information, or PCCH configuration information. In another example, a system message may include downlink transmission frequency information and initial downlink BWP, or BCCH configuration information and PCCH configuration information, or downlink transmission frequency information and BCCH configuration information, or downlink transmission frequency information and PCCH configuration information, or initial downlink BWP and BCCH configuration information, or initial downlink BWP and PCCH configuration information. In yet another example, a system message may include downlink transmission frequency information, initial downlink BWP and BCCH configuration information, or initial downlink BWP, BCCH configuration information and PCCH configuration information, or downlink transmission frequency information, BCCH configuration information and PCCH configuration information, or downlink transmission frequency information, initial downlink BWP and PCCH configuration information. In yet another example, a system message may include downlink transmission frequency information, initial downlink BWP, BCCH configuration information and PCCH configuration information.

[0292] In this step, the target network device can broadcast a system message within its network coverage. At this time, all terminals within the target network device's network coverage receive the system message; that is, the target terminals mentioned above receive the system message.

[0293] In some embodiments, the downlink transmit frequency information described above is used to indicate the transmit frequency of downlink small data packets. The initial downlink BWP is the initial downlink BWP configuration of the primary cell. The BCCH configuration information is a configuration relating to correcting the passing period of system messages. The PDCCH configuration information includes the default paging period, paging frame number and configuration, the number of paging occasions, and the first PDCCH monitoring occasion.

[0294] The default paging period is the default paging period broadcast in system messages. The paging frame number and configuration are used to derive the total number of paging frames and the paging frame offset. The number of paging occasions is used to indicate the number of paging occasions within each paging frame. A paging occasion is a group of PDCCH monitoring occasions consisting of multiple time slots for sending paging control information. The first PDCCH monitoring occasion is the first PDCCH monitoring occasion that indicates monitoring the paging occasion of a paging frame.

[0295] In embodiments of this disclosure, the order in which steps S1201 and S1202 are performed is not particularly limited.

[0296] In step S1203, the default paging period is determined as a second time period for sending paging messages.

[0297] In embodiments of the present disclosure, the second time period for the target network device to send a paging message may be the radio paging period included in the first release message.

[0298] In step S1204, the paging message is sent to the target terminal, whose current state is inactive, according to the second time period.

[0299] In step S1205, a connection resume request sent by the target terminal is received. The connection resume request is sent by the target terminal when a paging message containing a specified paging record for the target terminal itself is received. The specified paging record contains a mobile-terminated small data transmission instruction. The reason for connection resume in the connection resume request is a mobile-terminated small data transmission.

[0300] In step S1206, a downlink small data packet is sent to the target terminal based on the connection resumption request, and the target terminal receives the downlink small data packet.

[0301] Steps S1204 to S1206 above are the same as steps S1101 to S1103 above.

[0302] In some embodiments, the above connection resumption request may also include an uplink small data packet. When the above connection resumption request includes an uplink small data packet, embodiments of the present disclosure also provide a data transmission method according to the method shown in Figure 11. As shown in Figure 13, Figure 13 is a schematic flowchart of a twelfth data transmission method provided by embodiments of the present disclosure. This method includes the following steps:

[0303] In step S1301, a paging message is sent to the target terminal, whose current state is inactive, according to a second time period.

[0304] Step S1301 described above is the same as step S1101 described above.

[0305] In step S1302, a connection resume request sent by the target terminal is received. The connection resume request is sent by the target terminal when a paging message containing a designated paging record for the target terminal itself is received. The designated paging record contains a mobile-terminated small data transmission instruction. The reason for connection resume in the connection resume request is a mobile-terminated small data transmission.

[0306] In step S1302 described above, the connection resumption request sent by the target terminal to the target network device may further include an uplink small data packet. The uplink small data packet is a data packet that corresponds to the uplink data sent by the target terminal to the target network device, or to multiple subpackets obtained by dividing the uplink data.

[0307] In step S1303, when a connection resumption request is received, feedback information about the uplink small data packet is generated and the downlink small data packet is retrieved.

[0308] In step S1304, downlink small data packets and feedback information are sent to the target terminal.

[0309] In embodiments of the present disclosure, uplink small data packets are added during the connection resumption request so that downlink small data packet transmission is completed while uplink small data packet transmission is being performed, thereby improving data transmission efficiency.

[0310] In some embodiments, the embodiments of the present disclosure also provide a data transmission method according to the method shown in Figure 11. As shown in Figure 14, Figure 14 is a schematic flowchart of a thirteenth data transmission method provided by the embodiments of the present disclosure. This method includes the following steps:

[0311] In step S1401, a paging message is sent to the target terminal, whose current state is inactive, according to a second time period.

[0312] In step S1402, a connection resume request sent by the target terminal is received. The connection resume request is sent by the target terminal when a paging message containing a specified paging record for the target terminal itself is received. The specified paging record contains a mobile-terminated small data transmission instruction. The reason for connection resume in the connection resume request is a mobile-terminated small data transmission.

[0313] In step S1403, a downlink small data packet is sent to the target terminal based on the connection resumption request, and the target terminal receives the downlink small data packet.

[0314] Steps S1401 to S1403 above are the same as steps S1101 to S1103 above.

[0315] In step S1404, when the transmission of the downlink small data packet is complete, a second release message is sent to the target terminal. The second release message contains instruction information indicating a state switch, which the target terminal uses to switch its current state to inactive or idle based on the instruction information.

[0316] In this step, after sending a downlink small data packet to the target terminal, the target network device may send a second release message to the target terminal containing instructional information to indicate that the terminal is performing a state switch. Upon receiving the second release message, the target terminal may switch its current state to inactive or idle depending on the instructional information in the second release message.

[0317] By sending the second release message described above, the target terminal's state can be switched to an inactive or idle state in a timely manner after the mobile terminated small data transmission is complete.

[0318] In some embodiments, to further reduce signaling overhead during the mobile-terminated small data transmission process, when the target network device sends downlink small data packets to a target terminal, if there are two or more downlink small data packets, when the last downlink small data packet is sent, the target network device may add the last downlink small data packet to the second release message and send the last downlink small data packet together with the second release message to the target terminal, provided that the sum of the data volume of the last downlink small data packet and the data volume of the second release message is less than the bearing capacity of the radio channel.

[0319] For ease of understanding, the above process for small data transmission in an inactive state will be explained in conjunction with Figure 15. Figure 15 is a signaling diagram of the data transmission process in an inactive state provided by the embodiments of this disclosure.

[0320] In step S1501, the gNB sends an RRC release message to the UE. The RRC release message contains information about the suspension configuration. Report include.

[0321] The current state of the above UE is the connection state. The above suspension configuration information includes the wireless paging period. The above suspension configuration information may also include CG configuration information.

[0322] In step S1502, the UE switches its current state to an inactive state according to the suspension configuration information in the received RRC release message.

[0323] In step S1503, the gNB broadcasts a system message. The system message contains downlink common configuration information.

[0324] The above downlink common configuration information includes downlink transmit frequency information, initial downlink BWP, BCCH configuration information, and PCCH configuration information. The PCCH configuration information includes information such as the default paging period.

[0325] In step S1504, the gNB sends a paging message to the UE. The paging message includes terminal identification information that matches the fully inactive terminal identification information stored by the UE, and a designated paging record that includes a mobile-terminated small data transmission instruction.

[0326] In this step, the gNB sends the above paging message to the UE, using the above wireless paging period as the time period. In addition, the above designated paging record may also include a non-conflict access preamble.

[0327] In step S1505, the UE receives the paging message sent by the gNB.

[0328] In this step, the UE receives paging messages sent by the target network device, using the smaller of the above-mentioned wireless paging period and default paging period as the time period.

[0329] In step S1506, the UE sends an RRC resumption request to the gNB. The RRC resumption request includes the reason for resumption and the uplink small data packet. The reason for resumption is a mobile-terminated small data transmission.

[0330] The above RRC connection resumption request also includes a value indicating the access type (e.g., access type N above).

[0331] Depending on whether the above RRC release message contains CG configuration information and whether the paging message contains a non-conflict access preamble, the UE may send the above RRC connection resume request in a random access manner or in a configured grant type that matches the CG configuration.

[0332] In step S1506 above, if the target terminal does not have any uplink data to send to the target network device, the above RRC connection resumption request does not include the above uplink small data packet.

[0333] In step S1507, after receiving an RRC connection resumption request, the gNB generates feedback information corresponding to the uplink small data packet and sends the downlink small data packet and feedback information to the UE.

[0334] In step S1508, the UE receives downlink small data packets and feedback information.

[0335] In step S1509, the UE sends an uplink small data packet to the gNB.

[0336] In this step, if there are multiple uplink subpackets corresponding to uplink data, the UE continues to send the remaining unsent uplink subpackets to the gNB after receiving the feedback information described above.

[0337] In step S1510, the gNB sends downlink small data packets to the UE.

[0338] In this step, if there are multiple downlink small data packets corresponding to downlink data, the gNB proceeds to step S1 above. 507 After this is done, downlink small data packets can continue to be sent to the UE.

[0339] In step S1511, the gNB sends an RRC release message to the UE.

[0340] The above RRC release message contains information indicating that the state has been switched.

[0341] When there are multiple downlink small data packets corresponding to the downlink data described above, the RRC release message described above may also include the last downlink small data packet corresponding to the downlink data.

[0342] The uplink small data packets / downlink small data packets in steps S1509-S1511 above are subpackets corresponding to any remaining uplink data / downlink data that has not been sent after the first uplink small data packet / downlink small data packet transmission process. Steps S1509 and S1510 above can be performed multiple times, with only one small data packet being sent at a time.

[0343] In step S1512, the UE switches to an inactive or idle state depending on the received RRC release message.

[0344] In this step, the state of the UE after the switchover also changes depending on the different instruction information in the RRC release message.

[0345] Based on the same inventive concept, the embodiments of the present disclosure also provide a data transmission device according to the data transmission method provided by the embodiments of the present disclosure. As shown in Figure 16, Figure 16 is a first schematic diagram showing a data transmission device provided by the embodiments of the present disclosure. The data transmission device is applied to a target terminal and particularly comprises the following modules:

[0346] The first receiving module 1601 is used to receive paging messages issued by the target network device for a first time period when the current state of the target terminal is inactive.

[0347] The first dispatch module 1602 is used to send a reactivation request to the target network device when the received paging message contains a designated paging record of the target terminal, thereby causing the target network device to send a downlink small data packet to the target terminal based on the received reactivation request, where the designated paging record contains a mobile-terminated small data transmission instruction, and the reactivation reason in the reactivation request is mobile-terminated small data transmission.

[0348] The second receiving module 1603 is used to receive downlink small data packets sent by the target network device.

[0349] In some embodiments, the above-described paging message includes a paging record list, which is a list for recording the terminals being paged, and this paging record list includes at least one paging record.

[0350] In some embodiments, a paging record includes at least one of the following: terminal identification information for the terminal being paged, an access type, or a mobile-terminated small data transmission instruction. Terminal identification information includes a NAS ID assigned to the terminal by the NAS for core network paging and fully inactive terminal identification information for RAN paging; the access type is used to indicate whether the paging message is a paging message initiated by a PDU session not accessed by 3GPP; and the mobile-terminated small data transmission instruction is used to indicate that the paging message is used to trigger a mobile-terminated small data transmission.

[0351] In some embodiments, the paging record further includes a non-conflict access preamble indicating that non-conflict random access to the terminal is initiated.

[0352] In some embodiments, the data transmission device further includes: an analysis module for analyzing each paging record in a paging message received after receiving a paging message issued by a target network device according to a first time period; for each paging record obtained by the analysis, a first determination module for determining that the paging record is a designated paging record of the target terminal if the fully inactive terminal identification information in the paging record matches the fully inactive terminal identification information stored by the target terminal and the paging record includes a mobile-terminated small data transmission instruction; and the fully inactive terminal identification information in the paging record is targetThe system may include a second determination module for determining that this paging record is not the designated paging record for a target terminal when it does not match the fully inactive terminal identification information stored by the terminal, and / or when this paging record does not contain a mobile-terminated small data transmission instruction.

[0353] In some embodiments, the first dispatch module 1602 described above can be used in particular to send a connection resume request to a target network device based on CG configuration information when the received paging message contains a designated paging record of the target terminal, provided that the target terminal has configured grant (CG) configuration information stored.

[0354] In some embodiments, the first dispatch module 1602 described above can be used in particular to send a resume request to a target network device in a conflict access manner when the target terminal does not store configured grant (CG) configuration information, and the received paging message includes a designated paging record of the target terminal and the designated paging record does not include a conflict-free access preamble; and to send a resume request to a target network device in a conflict-free access manner when the received paging message includes a designated paging record of the target terminal and the designated paging record includes a conflict-free access preamble.

[0355] In some embodiments, the data transmission device may further include a determination module for determining whether a target terminal currently satisfies a preset connection initiation condition before sending a connection resume request to a target network device, wherein the preset connection initiation condition is that a mobile-terminated small data transmission instruction is received, or that a mobile-terminated small data transmission instruction is received and the downlink reference signal received power (RSRP) is greater than a preset threshold; and an implementation module for performing the step of sending a connection resume request to a target network device when the target terminal satisfies the preset connection initiation condition.

[0356] In some embodiments, the data transmission device further includes an implement module for sending another connection resumption request when another preset connection initiation condition is met, thereby causing the target terminal to send uplink data packets to the target network device after the connection corresponding to another connection resumption request has been reactivated, wherein the other preset connection initiation condition is that the amount of data on a wireless bearer configured for mobile-originated small data transmission is less than a preset data volume threshold, or the other preset connection initiation condition is that the amount of data on a wireless bearer configured for mobile-originated small data transmission is less than a preset data volume threshold and the uplink small data transmission resource is active.

[0357] In some embodiments, the above preset connection initiation conditions are: a mobile-terminated small data transmission instruction is received; or a mobile-terminated small data transmission instruction is received and the lower layers below the Radio Resource Control (RRC) layer are: Mobile Terminate This can be expressed as indicating that the trigger condition for sending small data has been met.

[0358] In some embodiments, a different preset connection initiation condition is that a higher layer above the Radio Resource Control (RRC) layer requests the resumption of an RRC connection, SIB1 includes a common configuration for small data transmission, a small data transmission configuration is configured, all uplink small data is mapped to the radio bearer of the small data transmission configuration, and a lower layer below the RRC layer... Mobile-Originated. This can be expressed as indicating that the trigger condition for sending small data has been met.

[0359] In some embodiments, the above data transmission device further enters an inactive state when the target terminal satisfies the preset connection initiation conditions. keru Small data transmission Did it fail? of Surveillance It may include a first start module that starts a timer for that purpose.

[0360] The above data transmission device further, connection It may include a second start module that starts a timer for monitoring the process and for sending a timeout instruction to the MAC entity when the target terminal does not meet the preset connection start conditions, the timeout instruction is in the CG configuration information of the small data transmission of the Configured Grant (CG) Timing Advance Timer Stop It is used to indicate something.

[0361] In some embodiments, the data transmission device may further include a release module for releasing stored configured grant (CG) configuration information when a target terminal moves from the current radio access network (RAN) cell to another RAN cell and initiates a connection reactivation process within the other RAN cell.

[0362] In some embodiments, the above connection resumption request is either a first connection resumption request or a second connection resumption request.

[0363] The first transmission module 1602 described above can be used in particular to select a first resumption request as a resumption request when an SIB1 transmitted by a base station indicates that the resumption request uses a full resumption identifier, or to select a second resumption request as a resumption request when the received SIB1 does not indicate the use of a full resumption identifier; and to restore preset security information from stored access layer context information, where the preset security information includes radio resource control (RRC) configuration, robust header compression (ROHC) status, stored mapping relationships between quality of service (QoS) flows and data resource bearers (DRBs), base station root keys, and complete Including a security key; the first transmission module 1602 can further be used to reconstruct the Packet Data Convergence Protocol (PDCP) entities of SIB1; to restore SIB1; for each radio bearer configured for mobile-terminated small data transmission, to reconstruct the configuration associated with the primary cell group of the PDCP configuration and the Radio Link Layer Control Protocol (RLC) bearer from the access layer context information and to reconstruct the PDCP entities of this radio bearer; to restart all radio bearers configured for mobile-terminated small data transmission; and to send a connection restart request to a target network device.

[0364] In some embodiments, the first and second connection reactivation requests described above each include a reactivation identifier, a reactivation integrity check code, and a reason for reactivating the connection, wherein the reactivation identifier of the first connection reactivation request is a fully inactive terminal identification information stored by the target terminal, and the reactivation identifier of the second connection reactivation request is a shortened inactive terminal identification information stored by the target terminal, the fully inactive terminal identification information and the shortened inactive terminal identification information are radio network temporary identifier values ​​of the inactive terminal, and are used by the target network to find the anchor point before the terminal entered the inactive state and the access layer context information stored by the anchor point, the fully inactive terminal identification information and the shortened inactive terminal identification information are of different sizes; the reactivation integrity check code is an identification information authentication token for terminal identification information authentication at the base station.

[0365] In some embodiments, the data transmission device may further include: a third receiving module for receiving a first release message issued by a target network device when the current state of the target terminal is connected, wherein the first release message includes suspension configuration information indicating that the terminal should implement an inactive state configuration; and a first switching module for switching the current state to an inactive state based on the suspension configuration information.

[0366] In some embodiments, the above suspension configuration information may include fully inactive terminal identification information, shortened inactive terminal identification information, wireless paging period, wireless notification area information, timer, next-hop chaining count value, and mobile-terminated small data transmission configuration information.

[0367] In some embodiments, the fully inactive terminal identification information and the abbreviated inactive terminal identification information are wireless network temporary identifier values ​​of an inactive terminal, used by the target network to find the anchor point node before the terminal entered the inactive state and the access layer context information stored by the anchor point node, and the fully inactive terminal identification information and the abbreviated inactive terminal identification information are of different sizes.

[0368] The wireless paging cycle mentioned above refers to the RAN paging cycle configured by the RAN node for inactive terminals.

[0369] The above wireless notification area information includes a cell list and a wireless area configuration list, and the cell list is the RAN area. as A list of configured cells, the wireless area configuration list is the RAN area code, or the RAN area RA Includes code.

[0370] The timer described above is used to trigger a periodic RAN-based notification area update (RNAU) process on the terminal.

[0371] The above next-hop chaining count value is used to calculate the security key after the connection is re-established.

[0372] The above configuration information for mobile-terminated small data transmission is: Mobile Terminate Small data transmission data resource bearer (DRB) list or Mobile Terminate Includes at least one of the small data transmission signaling radio bearer 2 (SRB2) instructions, Mobile Terminate The DRB list for small data transmissions shows the DRB identifiers for the small data transmission configuration. Mobile Terminate The SRB2 instruction for small data transmission indicates whether or not SRB2 is enabled in the terminal's small data transmission configuration.

[0373] In some embodiments, the above configuration information for mobile-terminated small data transmission is configured grant (CG) configuration Success The report further includes CG configuration information, which includes CG SSB RSRP thresholds, CG timing advance timers, CG timing advance verification configurations, and CG RSRP variation thresholds.

[0374] The above CG SSB RSRP threshold is the reference signal received power (RSRP) threshold selected by the SSB performing small data transmission based on CG resources.

[0375] The above-mentioned CG Timing Advance Timer is used for timing synchronization of small data transmissions.

[0376] The above CG timing advance verification configuration is used for timing advance (TA) verification configurations based on RSRP.

[0377] The CG RSRP fluctuation threshold mentioned above is the RSRP threshold for TA verification of small data transmissions.

[0378] In some embodiments, the first switching module: resets Media Access Control (MAC) to release the default MAC cell group configuration; applies suspension configuration information; and when the suspension configuration information includes CG configuration information, Mobile Terminate Each DRB in the DRB list for small data transmission and Mobile Terminate SRB2 instruction for small data transmission SRB2 shown in and Mobile TerminateTo determine the DRB and SRB2 during the small data transmission process, to reconstruct the RLC entity for each Radio Link Layer Control Protocol (RLC) bearer in the target terminal configuration, to trigger the Packet Data Convergence Protocol (PDCP) entity, to perform the session data unit (SDU) discard process for the restarted SRB2 and SRB1, to configure the CG resource for small data transmission for the MAC entity, and to indicate that the CG timing advance timer has been started; the current Access Layer Root Key (KgNB) and Integrity Protection Key (KRRCint) of the Radio Resource Control (RRC) signaling, the Robust Header Compression (ROHC) state, the stored mapping rules between the Quality of Service (QoS) flow and the Data Resource Bearer (DRB), the Cell Radio Network Temporary Identifier (C-RNTI) used in the Source Primary Cell (PCell), the Cell Identifier and Physical Cell Identifier of the Source PCell, and the new Radio Primary Secondary Cell (NR It is used to store all configuration parameters except for the Service Cell Common Configuration SIB, which includes the Special Cell (SpCell) common configuration in the PSCell synchronous reconfiguration message, the parameters in the PCell synchronous reconfiguration message, the parameters in the NR PSCell synchronous reconfiguration message, the mobility control information of the E-UTRA PSCell secondary cell group (SCG), the EN-DC primary secondary cell (PSCell) configuration, and the access layer context information of inactive terminals; to suspend all SRBs except SRB0 and DRB; to indicate that PDCP suspension should be implemented in the lower layers below the RRC layer for all DRBs; and to switch to an inactive state and perform cell reselection.

[0379] In some embodiments, the data transmission device may further include a fourth receiving module for receiving a system message broadcast by a target network device, the system message including at least one of downlink transmission frequency information, initial downlink bandwidth (BWP), broadcast control channel (BCCH) configuration information, or paging channel (PCCH) configuration information.

[0380] In some embodiments, the downlink transmission frequency information described above is used to indicate the transmission frequency of downlink small data packets.

[0381] The initial downlink BWP shown above is the initial downlink BWP configuration for the primary cell.

[0382] The BCCH configuration information described above is related to modifying the passing cycle of system messages.

[0383] The above PDCCH configuration information includes the default paging period, paging frame number and configuration, the number of paging occasions, and the first physical downlink control channel (PDCCH) monitoring occasion. The default paging period is the default paging period broadcast in system messages; the paging frame number and configuration are used to derive the total number of paging frames and the paging frame offset; the number of paging occasions is used to indicate the number of paging occasions in each paging frame; a paging occasion is a group of PDCCH monitoring occasions consisting of multiple time slots for sending paging control information; and the first PDCCH monitoring occasion is the first PDCCH monitoring occasion indicating that the paging occasion of a paging frame is being monitored.

[0384] In some embodiments, the data transmission device may include a third determination module for determining the smaller of the wireless paging period and the default paging period as a first time period for receiving paging messages when the target terminal is inactive, wherein the wireless paging period is the RAN paging period configured by the radio access network (RAN) side node for the inactive terminal.

[0385] In some embodiments, the above connection resumption request also includes an uplink small data packet.

[0386] The second receiving module 1603 described above can be used in particular to receive downlink small data packets sent by the target network device and feedback information sent by the target network device for uplink small data packets.

[0387] In some embodiments, the data transmission device may further include a fifth receiving module for receiving a second release message sent by a target network device when the transmission of a downlink small data packet is complete, wherein the second release message includes instruction information indicating a state switch; and a second switching module for switching the current state to an inactive or idle state based on the instruction information.

[0388] Based on the same inventive concept, the embodiments of the present disclosure also provide a data transmission device according to the data transmission method provided by the embodiments of the present disclosure. As shown in Figure 17, Figure 17 is a second schematic diagram showing a data transmission device provided by the embodiments of the present disclosure. The data transmission device is applied to a target network device and specifically comprises: a second transmission module 1701 for issuing paging messages to a target terminal according to a second time period, wherein the target terminal is currently in an inactive state; a sixth reception module 1702 for receiving a reactivation request sent by the target terminal, wherein the reactivation request is sent by the target terminal upon receiving a paging message containing a designated paging record of the target terminal itself, wherein the designated paging record contains a mobile-terminated small data transmission instruction, and the reason for reactivation in the reactivation request is a mobile-terminated small data transmission; and a third transmission module 1703 for sending downlink small data packets to the target terminal based on the reactivation request so that the target terminal receives downlink small data packets.

[0389] In some embodiments, the above-described paging message includes a paging record list, which is a list for recording the terminals being paged, and this paging record list includes at least one paging record.

[0390] In some embodiments, the above-described paging record includes at least one of the following: terminal identification information of the terminal being paged, access type, or mobile-terminated small data transmission instruction.

[0391] The above terminal identification information includes the NAS ID assigned to the terminal by the NAS for core network paging and the fully inactive terminal identification information for RAN paging. The access type is used to indicate whether the paging message is a paging message initiated by a PDU session not accessed by 3GPP. The mobile-terminated small data transmission instruction is used to indicate that the paging message is used to trigger a mobile-terminated small data transmission.

[0392] In some embodiments, the above-described paging record further includes a non-conflict access preamble indicating that non-conflict random access to the terminal is initiated.

[0393] In some embodiments, the above-mentioned reconnection request is either a first reconnection request or a second reconnection request, the first being sent by the target terminal when an SIB1 sent by the base station indicates that the reconnection request uses a full reconnection identifier, and the second being sent by the target terminal when an SIB1 sent by the base station does not indicate that the reconnection request uses a full reconnection identifier.

[0394] In some embodiments, the first connection resumption request and the second connection resumption request described above each include a resumption identifier, a resumption integrity check code, and a reason for connection resumption.

[0395] The reactivation identifier for the first connection reactivation request is the fully inactive terminal identification information stored by the target terminal, and the reactivation identifier for the second connection reactivation request is the abbreviated inactive terminal identification information stored by the target terminal. The fully inactive terminal identification information and the abbreviated inactive terminal identification information are temporary wireless network identifier values ​​of the inactive terminal, and are used by the target network to find the anchor point before the terminal entered the inactive state and the access layer context information stored by the anchor point. The fully inactive terminal identification information and the abbreviated inactive terminal identification information have different sizes. The reactivation integrity check code is an identification information authentication token for terminal identification information authentication at the base station.

[0396] In some embodiments, the data transmission device described above sends a first release message target It may further include a fourth transmission module for issuing to a terminal, the first release message being, target The system includes suspension configuration information indicating that an inactive state configuration should be implemented on the terminal, thereby causing the target terminal to switch its current state to an inactive state based on the suspension configuration information.

[0397] In some embodiments, the above suspension configuration information includes fully inactive terminal identification information, shortened inactive terminal identification information, wireless paging period, wireless notification area information, timer, next-hop chaining count value, and mobile-terminated small data transmission configuration information.

[0398] In some embodiments, the fully inactive terminal identification information and the abbreviated inactive terminal identification information are wireless network temporary identifier values ​​of an inactive terminal, used by the target network to find the anchor point node before the terminal entered the inactive state and the access layer context information stored by the anchor point node, and the fully inactive terminal identification information and the abbreviated inactive terminal identification information are of different sizes.

[0399] The wireless paging period mentioned above refers to the RAN paging period configured by the RAN-side node for inactive terminals.

[0400] The above wireless notification area information includes a cell list and a wireless area configuration list. The cell list is the RAN area. as This is a list of configured cells, and the radio area configuration list includes the RAN area code, or the RA code of the RAN area.

[0401] The timer described above is used to trigger a periodic RNAU process on the terminal.

[0402] The above next-hop chaining count value is used to calculate the security key after the connection is re-established.

[0403] The above configuration information for mobile-terminated small data transmission is: Mobile Terminate Small data transmission data resource bearer (DRB) list or Mobile Terminate Includes at least one of the small data transmission signaling radio bearer 2 (SRB2) instructions, Mobile Terminate The DRB list for small data transmissions shows the DRB identifiers for the small data transmission configuration. Mobile Terminate The SRB2 instruction for small data transmission indicates whether or not SRB2 is enabled in the terminal's small data transmission configuration.

[0404] In some embodiments, the above configuration information for mobile-terminated small data transmission is configured grant (CG) configuration Success The report further includes CG configuration information, which includes CG SSB RSRP thresholds, CG timing advance timers, CG timing advance verification configurations, and CG RSRP variation thresholds.

[0405] The CG SSB RSRP thresholds mentioned above are the RSRP thresholds selected by SSBs that perform small data transmissions based on CG resources.

[0406] The above-mentioned CG Timing Advance Timer is used for timing synchronization of small data transmissions.

[0407] The above CG timing advanced verification configuration is used for TA verification configurations based on RSRP.

[0408] The CG RSRP fluctuation threshold mentioned above is the RSRP threshold for TA verification of small data transmissions.

[0409] In some embodiments, the data transmission device may further include a broadcast module used to broadcast system messages. The system messages include at least one of downlink transmission frequency information, initial downlink BWP, BCCH configuration information, or PCCH configuration information.

[0410] In some embodiments, the downlink transmission frequency information described above is used to indicate the transmission frequency of downlink small data packets.

[0411] The initial downlink BWP shown above is the initial downlink BWP configuration for the primary cell.

[0412] The BCCH configuration information described above is related to modifying the passing cycle of system messages.

[0413] The above PDCCH configuration information includes the default paging period, paging frame number and configuration, number of paging occasions, and first PDCCH monitoring occasion, wherein the default paging period is the default paging period broadcast in system messages; the paging frame number and configuration are used to derive the total number of paging frames and the paging frame offset; the number of paging occasions is used to indicate the number of paging occasions in each paging frame; a paging occasion is a group of PDCCH monitoring occasions consisting of multiple time slots for sending paging control information; and the first PDCCH monitoring occasion is a first PDCCH monitoring occasion indicating that the paging occasions of a paging frame are being monitored.

[0414] In some embodiments, the data transmission device may further include a fourth determination module that determines a default paging period as a second time period for sending paging messages.

[0415] In some embodiments, the above connection resumption request also includes an uplink small data packet.

[0416] The third transmission module 1703 described above can be used in particular to generate feedback information for uplink small data packets and to acquire downlink small data packets when a connection resumption request is received; and to transmit downlink small data packets and feedback information to a target terminal.

[0417] In some embodiments, the data transmission device may further include a fifth transmission module used to send a second release message to a target terminal when the transmission of a downlink small data packet is complete, the second release message including instruction information indicating a state switch, thereby causing the target terminal to switch its current state to an inactive or idle state based on the instruction information.

[0418] An apparatus provided by embodiments of this disclosure may send a reactivation request to a target network device so as to trigger a small data transmission process between the target terminal and the target network device when the terminal is inactive, if the target terminal receives a paging message containing a designated paging record for the target terminal itself sent by the target network device while the terminal is inactive. The target network device may then send downlink small data packets to the target terminal based on the received reactivation request, and the target terminal may also receive the downlink small data packets, thereby enabling the downlink small data packet transmission process for the inactive terminal.

[0419] Furthermore, compared to related technologies in which an inactive terminal must switch to a connected state for data transmission, embodiments of the present disclosure introduce a new terminal access type, namely mobile-terminated small data transmission, through a mobile-terminated small data transmission instruction in a designated paging record, so that the terminal can receive downlink small data packets sent by a target network device while in an inactive state. This avoids the signaling overhead and latency consumption resulting from switching from an inactive state to a connected state, improves the transmission efficiency of downlink small data packets, saves signaling overhead for downlink small data packets, and thus effectively reduces signaling overhead and latency consumption in the data transmission process.

[0420] Based on the same inventive concept, the embodiments of the present disclosure also provide a data transmission system according to the data transmission method provided by the embodiments of the present disclosure. As shown in Figure 18, Figure 18 is a second schematic diagram showing the data transmission system provided by the embodiments of the present disclosure. The system shown in Figure 18 comprises a target terminal 1801 and a target network device 1802.

[0421] The target terminal 1801 described above is used to carry out the method shown in Figures 1 to 10.

[0422] The target network device 1802 described above is used to carry out the method shown in Figures 11 to 14.

[0423] A system provided by embodiments of this disclosure may send a reactivation request to a target network device when the target terminal is inactive, so as to trigger a small data transmission process between the target terminal and the target network device when the target terminal is inactive, if the target terminal receives a paging message containing a designated paging record for the target terminal itself sent by the target network device. The target network device may then send downlink small data packets to the target terminal based on the received reactivation request, and the target terminal may also receive the downlink small data packets, thereby enabling the downlink small data packet transmission process for the inactive terminal.

[0424] Furthermore, compared to related technologies in which an inactive terminal must switch to a connected state for data transmission, embodiments of the present disclosure introduce a new terminal access type, namely mobile-terminated small data transmission, through a mobile-terminated small data transmission instruction in a designated paging record, so that the terminal can receive downlink small data packets sent by a target network device while in an inactive state. This avoids the signaling overhead and latency consumption resulting from switching from an inactive state to a connected state, improves the transmission efficiency of downlink small data packets, saves signaling overhead for downlink small data packets, and thus effectively reduces signaling overhead and latency consumption in the data transmission process.

[0425] Based on the same inventive concept, the embodiments of the present disclosure also provide a target terminal according to the data transmission method provided by the embodiments of the present disclosure. As shown in Figure 19, the target terminal comprises a processor 1901, a communication interface 1902, a memory 1903, and a communication bus 1904. The processor 1901, the communication interface 1902, and the memory 1903 communicate with each other via the communication bus 1904.

[0426] Memory 1903 is used to store computer programs.

[0427] The processor 1901 is used to perform the following steps when executing a computer program stored in memory 1903: receiving a paging message issued by a target network device for a first time period when the current state of the target terminal is inactive; sending a reactivation request to the target network device when the received paging message contains a designated paging record of the target terminal, thereby causing the target network device to send a downlink small data packet to the target terminal based on the received reactivation request, wherein the designated paging record contains a mobile-terminated small data transmission instruction, and the reason for reactivation in the reactivation request is a mobile-terminated small data transmission; and receiving the downlink small data packet sent by the target network device.

[0428] Based on the same inventive concept, the embodiments of the present disclosure also provide a target network device according to the data transmission method provided by the embodiments of the present disclosure. As shown in Figure 20, the target terminal comprises a processor 2001, a communication interface 2002, a memory 2003, and a communication bus 2004. The processor 2001, the communication interface 2002, and the memory 2003 communicate with each other via the communication bus 2004.

[0429] Memory 2003 is used to store computer programs.

[0430] The processor 2001 is used to perform the following steps when executing a computer program stored in memory 2003: a step of issuing a paging message to a target terminal according to a second time period, wherein the target terminal is currently in an inactive state; a step of receiving a reactivation request sent by the target terminal, which is sent by the target terminal upon receiving a paging message containing a designated paging record of the target terminal itself, wherein the designated paging record contains a mobile-terminated small data transmission instruction, and the reason for reactivation in the reactivation request is a mobile-terminated small data transmission; and a step of sending downlink small data packets to the target terminal based on the reactivation request so that the target terminal receives downlink small data packets.

[0431] Depending on the embodiments of the target terminal and target network device provided by the embodiments of this disclosure, a reactivation request may be sent to the target network device when the target terminal is in an inactive state, such that the target terminal receives a paging message containing a designated paging record for the target terminal itself, sent by the target network device, triggering a small data transmission process between the target terminal and the target network device when the terminal is in an inactive state. The target network device may then send downlink small data packets to the target terminal based on the received reactivation request, and the target terminal also receives the downlink small data packets, thereby enabling the downlink small data packet transmission process for the inactive terminal.

[0432] Furthermore, compared to related technologies in which an inactive terminal must switch to a connected state for data transmission, embodiments of the present disclosure introduce a new terminal access type, namely mobile-terminated small data transmission, through a mobile-terminated small data transmission instruction in a designated paging record, so that the terminal can receive downlink small data packets sent by a target network device while in an inactive state. This avoids the signaling overhead and latency consumption resulting from switching from an inactive state to a connected state, improves the transmission efficiency of downlink small data packets, saves signaling overhead for downlink small data packets, and thus effectively reduces signaling overhead and latency consumption in the data transmission process.

[0433] The communication buses of the target terminals and target network devices mentioned above may be Peripheral Component Interconnect (PCI) buses or Extended Industry Standard Architecture (EISA) buses, etc. Communication buses can be divided into address buses, data buses, control buses, etc. For convenience of representation, buses are shown only with thick lines in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0434] The communication interface is used for communication between the target terminal, the target network device, and other devices.

[0435] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk memory. In some embodiments, the memory may also be at least one storage device located away from the aforementioned processor.

[0436] The above-mentioned processor may be a general-purpose processor comprising a central processing unit (CPU) or a network processor (NP), or it may be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate device or transistor logic device, or a discrete hardware component.

[0437] Based on the same inventive concept, the embodiments of the present disclosure also provide a computer-readable storage medium that stores a computer program which, when executed by a processor, performs the steps of the data transmission method of any of the embodiments described above.

[0438] Based on the same inventive concept, the embodiments of the present disclosure also provide a computer program product that, when executed on a computer, includes instructions causing the computer to perform any of the data transmission methods of the embodiments described above.

[0439] The embodiments described above can be implemented entirely or partially by software, hardware, firmware, or any combination thereof. When implemented in software, the embodiments can be implemented entirely or partially in the form of a computer program product. A computer program product includes one or more computer instructions. When the computer program instructions are loaded into a computer and executed, the processes or functions according to the embodiments of this disclosure are generated, entirely or partially. The computer may be a general-purpose computer, a dedicated computer, a computer network, or other programmable device. Computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, radio, microwave, etc.) from one website, computer, server, or data center to another website, computer, server, or data center. The computer-readable storage medium may be any available medium accessible by a computer or by a data storage device such as a server or data center, which includes one or more available media integrators. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state disks (SSDs)).

[0440] It should be noted that terms indicating relationships, such as “first” and “second” in this specification, are used merely to distinguish one entity or action from another, and do not necessarily require or suggest any actual relationship or order between these entities or actions. Furthermore, the terms “comprising,” “containing,” or any other variant thereof, cover non-exclusive inclusion, thereby including not only those elements but also other elements not explicitly enumerated, or elements specific to such process, method, item, or device. Unless further limited, an element defined by the phrase “comprising…” does not preclude the presence of additional identical elements in a process, method, item, or device that comprises that element.

[0441] The various embodiments described herein are described in relation to each other, and any identical or similar parts between the different embodiments can be referenced to one another. Each embodiment focuses on the differences from the other embodiments. In particular, the descriptions of embodiments such as apparatus, systems, target terminals, target network devices, computer-readable storage media, and computer program products are relatively simple, as they are substantially similar to the method embodiments, and relevant parts can be referenced to the descriptions of the method embodiments.

[0442] The foregoing describes only preferred embodiments of the Disclosure and does not limit the scope of protection of the Disclosure. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the Disclosure must also be included within the scope of protection of the Disclosure.

Claims

1. A data transmission method applicable to a target terminal, Receiving paging messages issued by a target network device according to a first time period when the current state of the target terminal is inactive, Sending a reconnection request to the target network device when the received paging message includes a designated paging record of the target terminal, wherein the designated paging record includes a mobile-terminated small data transmission instruction, and the reason for reconnection in the reconnection request is a mobile-terminated small data transmission. Receiving downlink small data packets sent by the aforementioned target network device, A data transmission method that includes this.

2. A data transmission method applied to a target terminal, Receiving paging messages issued by a target network device according to a first time period when the current state of the target terminal is inactive, Sending a reconnection request to the target network device when the received paging message includes a mobile-terminated small data transmission instruction and a lower layer below the Radio Resource Control (RRC) layer indicates that the trigger condition for mobile-terminated small data transmission is met, wherein the reason for reconnection in the reconnection request is mobile-terminated small data transmission. Receiving downlink small data packets sent by the aforementioned target network device, A data transmission method that includes this.

3. The data transmission method according to claim 1 or 2, wherein the paging message includes a paging record list, the paging record list includes at least one paging record, the paging record includes at least one of terminal identification information of the terminal being paged, an access type, or the mobile-terminated small data transmission instruction.

4. After receiving the paging message issued by the target network device, the data transmission method: This involves analyzing each paging record within the received paging message, For each paging record obtained through analysis, The data transmission method according to claim 1, further comprising determining that the fully inactive terminal identification information in the paging record matches the fully inactive terminal identification information stored by the target terminal, and that the paging record is the designated paging record of the target terminal if the paging record includes the mobile terminated small data transmission instruction.

5. If the target terminal stores configured grant (CG) configuration information, then when the received paging message includes the designated paging record of the target terminal, sending a connection resume request to the target network device is: The data transmission method according to claim 1, further comprising sending the connection resumption request to the target network device based on the CG configuration information when the received paging message includes the designated paging record of the target terminal.

6. Before sending the connection resumption request to the target network device, the data transmission method: Determining whether the target terminal currently satisfies preset connection initiation conditions, wherein the preset connection initiation conditions are that the mobile terminated small data transmission instruction is received, or that the preset connection initiation conditions are that the mobile terminated small data transmission instruction is received and the lower layers below the Radio Resource Control (RRC) layer indicate that the trigger conditions for mobile terminated small data transmission are met, wherein the trigger conditions include the downlink reference signal received power (RSRP) being greater than a preset threshold. When the target terminal satisfies the preset connection initiation conditions, the connection resumption request is sent to the target network device. The data transmission method according to claim 1 or 2, further comprising:

7. The further includes sending another connection restart request when another preset connection start condition is met, thereby causing the target terminal to send uplink data packets to the target network device after the connection corresponding to another connection restart request has been restarted, wherein the other preset connection start condition is that a higher layer above the RRC layer requests the restart of an RRC connection, a System Information Block Type 1 (SIB1) includes a common configuration for small data transmission, a small data transmission configuration is configured, and all uplink small data is sent to the wireless bearer of the small data transmission configuration. The data transmission method according to claim 1 or 2, wherein the layer is ripped and the lower layers below the RRC layer indicate that a trigger condition for mobile-originated small data transmission is met, the trigger condition being that the amount of data of a wireless bearer configured for mobile-originated small data transmission is less than a preset data volume threshold, or the amount of data of the wireless bearer configured for mobile-originated small data transmission is less than the preset data volume threshold and the uplink small data transmission resource is enabled.

8. The aforementioned connection resumption request is either a first connection resumption request or a second connection resumption request. Sending a connection resumption request to the target network device is: A data transmission method according to claim 1 or 2, comprising selecting the first connection resumption request as the connection resumption request when the SIB1 transmitted by the base station indicates that the connection resumption request uses a full resumption identifier, or selecting the second connection resumption request as the connection resumption request when the received SIB1 does not indicate the use of the full resumption identifier.

9. Sending a connection resumption request to the target network device is: For each radio bearer configured for mobile-terminated small data transmission, the configuration associated with the primary cell group and the Radio Link Layer Control Protocol (RLC) bearer in the PDCP configuration is reconstructed from the access layer context information. Restarting all radio bearers configured for the aforementioned mobile-terminated small data transmission, Sending the aforementioned connection resumption request to the target network device, It further includes, The first connection resumption request and the second connection resumption request each include a resumption identifier, a resumption integrity check code, and the reason for resuming the connection, The restart identifier for the first connection restart request is the fully inactive terminal identification information stored by the target terminal, the restart identifier for the second connection restart request is the abbreviated inactive terminal identification information stored by the target terminal, the fully inactive terminal identification information and the abbreviated inactive terminal identification information are the wireless network temporary identifier values ​​of the inactive terminal, and are used by the target network to find the anchor point before the terminal entered the inactive state and the access layer context information stored by the anchor point, the fully inactive terminal identification information and the abbreviated inactive terminal identification information are of different sizes, and The data transmission method according to claim 8, wherein the restart integrity check code is an identification information authentication token for terminal identification information authentication at the base station.

10. When the current state of the target terminal is a connected state, the data transmission method is: Receiving a first release message issued by the target network device, wherein the first release message includes suspension configuration information indicating that an inactive state configuration is to be implemented on the terminal, and the suspension configuration information includes fully inactive terminal identification information, shortened inactive terminal identification information, wireless paging period, wireless notification area information, timer, next-hop chaining count value, and mobile terminated small data transmission configuration information. Based on the suspension configuration information, the current state is switched to the inactive state, The data transmission method according to claim 1 or 2, further comprising:

11. The fully inactive terminal identification information and the abbreviated inactive terminal identification information are wireless network temporary identifier values ​​of the inactive terminal, and are used by the target network to find the anchor point node before the terminal entered the inactive state and the access layer context information stored by the anchor point node, and the fully inactive terminal identification information and the abbreviated inactive terminal identification information have different sizes. The aforementioned wireless paging period refers to the RAN paging period configured by the wireless access network (RAN) side node for the inactive terminal. The wireless notification area information includes a cell list and a wireless area configuration list, the cell list is a list of cells configured as a RAN area, and the wireless area configuration list includes a RAN area code or the RA code of the RAN area. The timer is used to trigger a periodic RAN-based notification area update (RNAU) process in the terminal. The aforementioned next-hop chaining count value is used to calculate the security key after the connection is resumed, and also, The data transmission method according to claim 10, wherein the configuration information for the mobile terminated small data transmission includes at least one of a data resource bearer (DRB) list for the mobile terminated small data transmission or a signaling radio bearer 2 (SRB2) instruction for the mobile terminated small data transmission, the DRB list for the mobile terminated small data transmission indicates a DRB identifier for the small data transmission configuration, and the SRB2 instruction for the mobile terminated small data transmission indicates whether or not the terminal has an SRB2 for the small data transmission configuration.

12. The configuration information for mobile-terminated small data transmission further includes configured grant (CG) configuration information, the CG configuration information includes a CG SSB RSRP threshold, a CG timing advance timer, a CG timing advance verification configuration, and a CG RSRP variation threshold. The CG SSB RSRP threshold is a reference signal received power (RSRP) threshold selected by the SSB that performs small data transmission based on CG resources. The aforementioned CG timing advance timer is used for timing synchronization of small data transmissions. The aforementioned CG timing advance verification configuration is used for timing advance (TA) verification configurations based on RSRP, and, The data transmission method according to claim 10, wherein the CG RSRP fluctuation threshold is the RSRP threshold for TA verification of small data transmission.

13. Switching the current state to the inactive state based on the suspension configuration information is: This involves resetting Media Access Control (MAC) and releasing the default MAC cell group configuration. Applying the aforementioned suspension configuration information, When the suspension configuration information includes CG configuration information, the following are indicated: determining each DRB in the DRB list for mobile-terminated small data transmission and the SRB2 indicated in the SRB2 instruction for mobile-terminated small data transmission as the DRB and SRB2 during the mobile-terminated small data transmission process; reconstructing the RLC entity for each Radio Link Layer Control Protocol (RLC) bearer in the target terminal configuration; triggering the Packet Data Convergence Protocol (PDCP) entity to perform the session data unit (SDU) discard process for the restarted SRB2 and SRB1; configuring the CG resources for small data transmission for the MAC entity; and starting the CG timing advance timer. The current access layer root key (KgNB) and integrity protection key (KRRCint) of the radio resource control (RRC) signaling, the robust header compression (ROHC) state, the stored mapping rules between the quality of service (QoS) flow and the data resource bearer (DRB), the cell radio network temporary identifier (C-RNTI) used in the source primary cell (PCell), the cell identifier and physical cell identifier of the source PCell, the special cell (SpCell) common configuration in the synchronous reconfiguration message of the New Radio Primary Secondary Cell (NR PSCell), the parameters in the synchronous reconfiguration message of the PCell, the parameters in the synchronous reconfiguration message of the NR PSCell, E-UTRA The system stores all other configuration parameters except for the Service Cell Common Configuration SIB, which includes the mobility control information of the secondary cell group (SCG) of the PSCell, the primary and secondary cell (PSCell) configuration of the EN-DC, and the access layer context information of the inactive terminal. To suspend all SRBs except SRB0 and DRB, This indicates that PDCP suspension will be implemented in all lower layers of the DRB, wherein the lower layer is below the RRC layer, and the PDCP suspension will be implemented in the lower layer. Switching to the aforementioned inactive state and performing cell reselection, The data transmission method according to claim 11, including the method described in claim 11.

14. The system further includes receiving a system message broadcast by the target network device, the system message including at least one of downlink transmission frequency information, initial downlink bandwidth (BWP), broadcast control channel (BCCH) configuration information, or paging channel (PCCH) configuration information. The downlink transmission frequency information is used to indicate the transmission frequency of the downlink small data packet. The aforementioned initial downlink BWP is the initial downlink BWP configuration of the primary cell. The BCCH configuration information is a configuration relating to correcting the passing period of the system message, The data transmission method according to claim 1 or 2, wherein the PDCCH configuration information includes a default paging period, a paging frame number and configuration, a number of paging occasions, and a first physical downlink control channel (PDCCH) monitoring occasion, the default paging period being the default paging period broadcast in the system message, the paging frame number and configuration being used to derive the total number of paging frames and the paging frame offset, the number of paging occasions being used to indicate the number of paging occasions within each paging frame, the paging occasion being a group of PDCCH monitoring occasions consisting of multiple time slots for sending paging control information, and the first PDCCH monitoring occasion being a first PDCCH monitoring occasion indicating monitoring the paging occasion of a paging frame.

15. The data transmission method according to claim 1 or 2, further comprising determining the smaller of the wireless paging period and the default paging period as the first time period for receiving the paging message when the target terminal is in the inactive state, wherein the wireless paging period is the RAN paging period configured by the wireless access network (RAN) side node for the inactive terminal, and the default paging period is the default paging period broadcast in a system message.

16. The aforementioned connection resumption request further includes an uplink small data packet, Receiving downlink small data packets sent by the aforementioned target network device is: A data transmission method according to claim 1 or 2, comprising receiving the downlink small data packet sent by the target network device and feedback information sent by the target network device in response to the uplink small data packet.

17. Receiving a second release message sent by the target network device when the transmission of the downlink small data packet is completed, wherein the second release message includes instruction information indicating a state switch. Based on the instruction information, the current state is switched to the inactive state or idle state. The data transmission method according to claim 1 or 2, further comprising:

18. A data transmission method applicable to a target network device, Issuing a paging message to a target terminal according to a second time period, wherein the target terminal is currently in an inactive state when issuing the paging message. Receiving a connection resume request sent by the target terminal, wherein the connection resume request is sent by the target terminal upon receiving the paging message which includes a designated paging record of the target terminal itself, the designated paging record which includes a mobile-terminated small data transmission instruction, and the reason for resuming the connection in the connection resume request is a mobile-terminated small data transmission. Based on the aforementioned connection resumption request, a downlink small data packet is sent to the target terminal. A data transmission method, including the transmission method.

19. Memory for storing computer programs, A processor that executes the computer program stored in the memory to perform the data transmission method described in claim 1 or 2, Communication interface, A target terminal comprising a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus.

20. Memory for storing computer programs, A processor that executes the computer program stored in the memory to perform the data transmission method described in claim 18, Communication interface, A target network device comprising a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus.

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