CN114727414A

CN114727414A - Data transmission method and related device

Info

Publication number: CN114727414A
Application number: CN202110051718.3A
Authority: CN
Inventors: 张梦晨; 酉春华; 郭英昊
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-01-04
Filing date: 2021-01-14
Publication date: 2022-07-08

Abstract

The embodiment of the application provides a data transmission method, which is applied to a terminal, wherein the terminal is in a non-connection state, and the method comprises the following steps: a terminal obtains a first data packet, wherein the first data packet is packet data; the terminal and the network equipment perform a packet data transmission process; the transmission process of the packet data comprises the steps that a terminal sends a random access preamble, a first data packet and a Radio Resource Control (RRC) request message to network equipment, and the terminal receives an RRC response message sent by the network equipment; in the packet data transmission process, the terminal obtains a second data packet; if the second data packet is packet data, the terminal sends a first Scheduling Request (SR) to the network equipment, wherein the first SR is used for requesting scheduling resources; the terminal receives a first transmission resource scheduled for the terminal by the network equipment in response to the first SR; the terminal sends the second data packet to the network device using the first transmission resource. By adopting the embodiment of the application, the transmission delay of the second data packet can be reduced under the condition that the transmission of the first data packet is not influenced.

Description

Data transmission method and related device

Technical Field

The present application relates to the field of communications technologies, and in particular, to a data transmission method and a related apparatus.

Background

In the communication system, a Radio Resource Control (RRC) layer may be included in a communication protocol stack of the terminal and the network device. There are currently three RRC states for a terminal, namely, an RRC IDLE (RRC IDLE) state, an RRC inactive (RRC INACTIVE) state, and an RRC CONNECTED (RRC CONNECTED) state.

Generally, when a terminal is in an RRC CONNECTED state, data can be transmitted between the terminal and a network device. However, in some scenarios, a terminal in the RRC IDLE state or the RRC INACTIVE state needs to transmit a small data packet, which may be referred to as a small data packet (small data), such as an instant messaging message, a heartbeat packet, and periodic data. And the signaling required for the terminal to enter the RRC CONNECTED state from the RRC IDLE state or RRC INACTIVE state is even larger than small data, thereby causing unnecessary power consumption and signaling overhead for the terminal. In order to avoid the situation, the terminal in the RRC IDLE state or RRC INACTIVE state can transmit the small data in the Random Access (RA) process without entering the RRC CONNECTED state and then transmitting the small data. The above transmission process may be referred to as a Small Data Transmission (SDT).

But with SDT, the terminal may get a new data packet to be transmitted. At this time, the terminal may trigger reporting of a Buffer Status Reporting (BSR) to the network device, but may not report transmission resources of the BSR, and then the terminal may trigger reporting of a scheduling req (scheduling req terminal st, SR) to the network device. However, the network device usually only allocates the SR resource to the terminal in the RRC CONNECTED state, and thus the terminal performing SDT does not report the transmission resource of the SR. At this time, the terminal can only initiate a new RA or SDT to request the network device for scheduling resources, but this may affect the transmission delay of the currently transmitted small data or new data packet. For example, when a new RA or SDT is initiated after the currently performed SDT is finished, the transmission delay of a new packet may be large. Or, stopping the currently performed SDT and directly initiating a new RA or SDT, and the delay of the currently transmitted small data may be large.

Disclosure of Invention

The embodiment of the application discloses a data transmission method and a related device, which can improve the transmission delay of a new data packet without influencing the transmission delay of currently transmitted packet data.

In a first aspect, an embodiment of the present application provides a data transmission method, which is applied to a user equipment terminal, where the terminal is in a non-connected state, and the method includes: the terminal acquires a first data packet, wherein the first data packet is packet data; the terminal and the network equipment perform a packet data transmission process; the small packet data transmission process comprises the steps that the terminal sends a random access preamble, the first data packet and a Radio Resource Control (RRC) request message to the network equipment, and the terminal receives an RRC response message sent by the network equipment; in the packet data transmission process, the terminal obtains a second data packet; if the second data packet is packet data, the terminal sends a first Scheduling Request (SR) to the network equipment, wherein the first SR is used for requesting scheduling resources; the terminal receives a first transmission resource scheduled by the network equipment for the terminal in response to the first SR; and the terminal sends the second data packet terminal to the network equipment by using the first transmission resource.

The packet data is a data packet whose data amount is smaller than a preset threshold (for example, the size of a transmission block indicated by the base station), or a data packet whose data label is packet data, or a data packet whose data type belongs to packet data, and the like. The data packet of the non-small packet data may be referred to as large packet data, and may be a data packet whose data amount is greater than or equal to a preset threshold, or a data packet whose data tag is large packet data, or a data packet whose data type belongs to large packet data, and so on. For example, data of which the data type is a heartbeat packet is packet data, and data of which the data type is a file, video or audio is packet data. The packet data is, for example, an instant messaging message, a heartbeat packet, periodic data, and the like.

Optionally, the process of packet data transmission performed by the terminal and the network device may be replaced by: and the terminal sends a random access preamble for transmitting the packet data or the first data packet to the network equipment. Optionally, the second data packet is obtained by the terminal when the terminal sends the random access preamble to the network device, or obtained by the terminal after the terminal sends the random access preamble to the network device.

In the embodiment of the application, in the process of packet data transmission between the terminal and the network device, the terminal generates the second data packet, and the terminal can timely notify the network device of new packet data arrival through the first SR. In response to the first SR, the network device may dynamically schedule the first transmission resource for the terminal to transmit the second data packet using the first transmission resource. Therefore, the terminal can continuously transmit new packet data in a non-connection state without initiating a new RA or SDT, and unnecessary signaling overhead and power consumption are avoided. Meanwhile, the transmission delay of the second data packet can be reduced under the condition that the transmission delay of the first data packet is not influenced.

In one possible implementation, the first SR is configured to request scheduling resources of the small packet data, and the method further includes: if the second data packet is big packet data, the terminal sends a second SR to the network device, the second SR is used for requesting scheduling resources of the big packet data, and the RRC response message in the small packet data transmission process is sent by the network device in response to the second SR; the terminal enters an RRC connected state in response to the RRC response message; and the terminal sends the second data packet to the network equipment.

In the embodiment of the application, in the process of packet data transmission between the terminal and the network device, the terminal generates the second data packet, and the terminal can timely notify the network device of new arrival of big packet data through the second SR. In response to the second SR, the network device may instruct the terminal to enter an RRC connected state, so that the terminal transmits the second data packet in the RRC connected state. The terminal does not need to initiate a new RA or SDT, thereby saving transmission resources and avoiding unnecessary signaling overhead and power consumption. Meanwhile, the transmission delay of the second data packet can be reduced under the condition that the transmission delay of the first data packet is not influenced.

In one possible implementation, the method further includes: if the second data packet is big packet data, the terminal executes a random access process; the terminal enters an RRC (radio resource control) connection state based on the random access process; and the terminal sends the second data packet to the network equipment.

In one possible implementation manner, the performing, by the terminal and the network device, a random access procedure includes: the terminal interrupts the packet data transmission process and executes the random access process; after the terminal enters an RRC connected state based on the random access process, the method further comprises the following steps: and the terminal sends the first data packet to the network equipment.

In the embodiment of the application, when the terminal and the network device transmit the small packet data, the terminal can interrupt the small packet data process and execute the random access process to request to enter the RRC connection state. After entering a connection state, the terminal transmits the small packet data (namely, the first data packet) and the new big packet data (namely, the second data packet), so that the transmission delay of the big packet data is prevented from being influenced.

In one possible implementation, the method further includes: and under the condition that the terminal does not send BSR resources to the network equipment, the terminal triggers and reports the first SR or the second SR.

In the embodiment of the application, during the packet data transmission process of the terminal and the network device, the terminal generates the second data packet, and the terminal can trigger the report of the BSR. If there is no resource for reporting the BSR, the terminal may trigger the report SR. If the first SR and/or the second SR are configured, the terminal may notify the network device that a new data packet arrives through the first SR and/or the second SR in time, so that the transmission delay of the second data packet is reduced without affecting the transmission delay of the first data packet. If the second data packet is the big packet data and the second SR is not configured, the terminal may perform a random access procedure, thereby entering an RRC connected state to transmit new big packet data, and reducing a transmission delay of the second data packet.

In a possible implementation manner, when the terminal and the network device perform the packet data transmission process, the terminal recovers a data radio bearer DRB for transmitting the packet data and a DRB for transmitting the large packet data.

In a possible implementation manner, the logical channel corresponding to the first SR is a logical channel included in a first DRB, the first DRB is a DRB used for transmitting packet data, the logical channel corresponding to the second SR is a logical channel included in a second DRB, and the second DRB is a DRB used for transmitting packet data.

In a possible implementation manner, when the terminal sends the first SR to the network device, the terminal maintains uplink synchronization; and/or when the terminal sends the second SR to the network equipment, the terminal keeps uplink synchronization.

In the embodiment of the application, the terminal generates the second data packet in the process of packet data transmission by the terminal and the network device. The terminal can timely inform the network equipment of the arrival of a new data packet through the first SR and/or the second SR under the condition of keeping uplink synchronization, thereby reducing multipath interference and improving transmission quality.

In a possible implementation manner, before the terminal and the network device perform the packet data transmission process, the method further includes: the terminal receives a configuration message sent by the network equipment, wherein the configuration message comprises information of the first SR and the second SR; the terminal determines that the information of the first SR and the second SR takes effect; or, before the terminal and the network device perform the packet data transmission process, the method further includes: the terminal receives a configuration message sent by the network equipment, wherein the configuration message comprises information of the first SR and the second SR; the terminal receives an effective message sent by the network equipment, wherein the effective message is used for indicating that the information of the first SR and the second SR takes effect; wherein the information of the first and second SRs includes configuration information of the first and second SRs and resource information of the first and second SRs.

In the embodiment of the application, the mode that the network equipment indicates the configuration information of the first SR and the second SR of the terminal to take effect is flexible, the network equipment can flexibly select the mode for indicating the configuration information to take effect according to the network condition, and the application scene is wider.

In one possible implementation, the method further includes: when a preset condition is met, the terminal releases configuration information of the first SR and the second SR, and/or resource information of the first SR and the second SR; the preset condition comprises at least one of the following conditions: the terminal performs cell reselection, the terminal does not maintain uplink synchronization, the terminal receives an RRC response message sent by the network device, and the RRC response message is used to indicate any one of the following: and the terminal enters an RRC connection state, and the transmission process of the small packet data is finished.

In the embodiment of the application, the terminal can select whether to release the configuration information and/or the resource information of the first SR and the second SR according to actual conditions and requirements, so that unnecessary power consumption is avoided.

In one possible implementation manner, the capability information of the first SR and the second SR is obtained by the network device from a network device to which the terminal is previously connected.

In the embodiment of the application, even if the network device connected to the terminal is switched, the network device newly connected to the terminal can acquire the configuration information of the first SR and the second SR of the terminal from the network device previously connected to the terminal, so that the network device newly connected to the terminal can configure the first SR and the second SR for the terminal. Therefore, the terminal configured with the first SR and the second SR can selectively use the first SR and the second SR to notify the network device that a new data packet arrives according to actual conditions, thereby reducing data transmission delay.

In one possible implementation, the method further includes: the terminal determines a first beam, and the terminal determines the first SR according to the first beam; the first beam is a beam for the terminal to send the first SR to the network device, or a beam corresponding to the first SR, the network device is configured to determine a second beam according to the first SR after receiving the first SR, and the second beam is a beam for the network device to send downlink data to the terminal; or, the terminal determines a first beam, and the terminal determines the second SR according to the first beam; the first beam is a beam for the terminal to send the second SR to the network device, or a beam corresponding to the second SR; the network device is configured to determine a second beam according to the second SR after receiving the second SR, where the second beam is a beam for the network device to send downlink data to the terminal.

In the embodiment of the application, the network device may complete the beam update through the first SR, so as to improve the subsequent transmission quality.

In a second aspect, an embodiment of the present application provides another data transmission method, which is applied to a user equipment terminal, where the terminal is in a non-connected state, and the method includes: the terminal obtains a first data packet; the first data packet is packet data; the terminal and the network equipment perform a packet data transmission process; the small packet data transmission process comprises the steps that the terminal sends a random access preamble, the first data packet and an RRC request message to the network equipment, and the terminal receives an RRC response message sent by the network equipment; in the packet data transmission process, the terminal obtains a second data packet; under the condition that the second data packet is packet data, the terminal sends a first BSR to the network equipment to obtain a first transmission resource scheduled for the terminal by the network equipment in response to the first BSR; and the terminal sends the second data packet to the network equipment by using the first transmission resource.

In the embodiment of the application, during the packet data transmission process of the terminal and the network device, the terminal generates the second data packet, and the terminal can trigger the report of the BSR. The terminal can inform the network device of new packet data arrival in time through the BSR, and the network device can dynamically schedule the first transmission resource for the terminal, so that the terminal uses the first transmission resource to send a new packet, and the terminal can continue to transmit the packet data in a non-connection state. The terminal does not need to initiate a new RA or SDT, thereby saving transmission resources and avoiding unnecessary signaling overhead and power consumption. And reducing the transmission delay of the second data packet under the condition of not influencing the transmission delay of the first data packet.

In one possible implementation, the method further includes: when the second data packet is big packet data, the terminal sends a second BSR to the network equipment, and the terminal receives an RRC response message sent by the network equipment to the terminal in response to the second BSR; and the terminal responds to the RRC response message to enter an RRC connection state, and the terminal sends the second data packet to the network equipment.

In a possible implementation manner, in the above case that the second data packet is packet data, the terminal sends a first BSR to the network device to obtain a first transmission resource that the network device schedules for the terminal in response to the first BSR; the terminal sends the second data packet to the network device by using the first transmission resource, which may be replaced with: under the condition that the second data packet is big packet data, the terminal sends a second BSR to the network equipment, and the terminal receives an RRC response message sent to the terminal by the network equipment in response to the second BSR; and the terminal responds to the RRC response message to enter an RRC connection state, and the terminal sends the second data packet to the network equipment.

In a possible implementation manner, the first BSR includes a first field indicating a transmission resource for acquiring packet data, and the first BSR includes a second field indicating a transmission resource for acquiring large packet data.

In one possible implementation, the first field indicates a first logical channel group, the first logical channel group includes logical channels for transmitting small packet data, and the second field indicates a second logical channel group, the second logical channel group includes logical channels for transmitting large packet data.

Optionally, the first field with the value of the first value indicates that packet data to be transmitted exists, the first field with the value of the second value indicates that packet data to be transmitted does not exist, the second field with the value of the first value indicates that large packet data to be transmitted exists, and the second field with the value of the second value indicates that large packet data to be transmitted does not exist.

In the embodiment of the application, the mode that the BSR indicates that the small packet data or the large packet data to be transmitted exists is flexible, and the application scene is wider.

In a third aspect, an embodiment of the present application provides another data transmission method, which is applied to a user equipment terminal, where the terminal is in a non-connected state, and the method includes: the terminal acquires a first data packet, wherein the first data packet is packet data; the terminal sends a random access preamble to the network equipment; the terminal obtains a second data packet; the terminal sends a third data packet, an RRC request message and first indication information to the network equipment, wherein the first indication information is used for requesting to schedule resources; the third data packet is a data packet with higher priority in the first data packet and the second data packet; the terminal receives a first transmission resource scheduled for the terminal by the network equipment in response to the first indication information; and the terminal sends the second data packet to the network equipment by using the first transmission resource.

In the embodiment of the application, the terminal generates the second data packet in the process of packet data transmission by the terminal and the network device. The terminal can send a third data packet with higher priority in the current packet data transmission process, and timely informs the network equipment of new packet data arrival through the first indication information, so that the influence of the low-priority data packet on the transmission of the high-priority data packet is avoided, and the transmission delay of the low-priority data packet is reduced. In addition, the terminal can continue to transmit the packet data with low priority in the non-connection state without initiating a new RA or SDT, thereby avoiding unnecessary signaling overhead and power consumption.

In a possible implementation manner, the priority of the terminal sending the third data packet is higher than the priority of the terminal sending a BSR, and the sending, by the terminal, the third data packet, the RRC request message, and the first indication information to the network device includes: and under the condition that the terminal does not send the resource of the BSR to the network equipment, the terminal sends the third data packet, the RRC request message and the first indication information to the network equipment.

In a fourth aspect, an embodiment of the present application provides a data transmission method, which is applied to a network device, and the method includes: the network equipment and the terminal in the non-connection state carry out a packet data transmission process; the small packet data transmission process comprises the steps that the network equipment receives a random access preamble, a first data packet and an RRC request message sent by the terminal, and the network equipment sends an RRC response message to the terminal; the first data packet is packet data obtained by the terminal; the network equipment receives a first SR sent by the terminal, wherein the first SR is sent by the terminal when a second data packet is packet data, and the second data packet is obtained by the terminal in the transmission process of the packet data; the network equipment responds to the first SR to schedule first transmission resources for the terminal; and the network equipment receives the second data packet sent by the terminal by using the first transmission resource.

In one possible implementation, the method further includes: the network equipment receives a second SR sent by the terminal, wherein the second SR is sent by the terminal when the second data packet is big packet data; the RRC response message in the packet data transmission process is sent by the network equipment in response to the second SR, and the RRC response message is used for indicating the terminal to enter an RRC connected state; and the network equipment receives the second data packet sent by the terminal in the RRC connection state.

In one possible implementation, the method further includes: and the network equipment receives the second data packet sent by the terminal in an RRC connection state, wherein the RRC connection state is entered by the terminal in a random access process executed under the condition that the second data packet is big packet data.

In one possible implementation manner, the capability information of the first SR and the second SR is obtained by the network device from a network device to which the terminal is previously connected. In a possible implementation manner, the first SR is determined by the terminal according to a first beam, where the first beam is a beam for the terminal to transmit the first SR to the network device, or a beam corresponding to the first SR, and the method further includes: after receiving the first SR, the network device determines a second beam according to the first SR, where the second beam is a beam for the network device to send downlink data to the terminal; or the like, or, alternatively,

the second SR is determined by the terminal according to a first beam, where the first beam is a beam for the terminal to transmit the second SR to the network device, or a beam corresponding to the second SR, and the method further includes: and after receiving the second SR, the network device determines a second beam according to the second SR, where the second beam is a beam for the network device to send downlink data to the terminal.

In a fifth aspect, an embodiment of the present application provides a data transmission method, which is applied to a network device, and the method includes: the network equipment and the terminal in the non-connection state carry out a packet data transmission process; the small packet data transmission process comprises the steps that the network equipment receives a random access preamble, a first data packet and an RRC request message sent by the terminal, and the network equipment sends an RRC response message to the terminal; the first data packet is packet data obtained by the terminal; the network equipment receives a first BSR sent by the terminal, wherein the first BSR is sent by the terminal when a second data packet is packet data, and the second data packet is obtained by the terminal in the packet data transmission process; the network device scheduling a first transmission resource for the terminal in response to the first BSR; and the network equipment receives the second data packet sent by the terminal by using the first transmission resource.

In a possible implementation manner, the first BSR includes a first field indicating acquisition of transmission resources for packet data, and the first BSR includes a second field indicating acquisition of transmission resources for large packet data.

In a sixth aspect, an embodiment of the present application provides a data transmission method, which is applied to a network device, and the method includes: the network equipment receives a random access preamble sent by the terminal, wherein the random access preamble is sent after the terminal obtains a first data packet, and the first data packet is packet data; the network equipment receives a third data packet, an RRC request message and first indication information sent by the terminal, wherein the first indication information is sent after the terminal obtains a second data packet, and the second data packet is packet data obtained when or after the terminal sends the random access preamble to the network equipment; the third data packet is a data packet with higher priority in the first data packet and the second data packet; the network equipment responds to the first indication information to schedule first transmission resources for the terminal; and the network equipment receives the second data packet sent by the terminal by using the first transmission resource.

In a possible implementation manner, the priority of the terminal for sending the third packet is higher than the priority of the terminal for sending a BSR, and the first indication information is sent by the terminal without sending the BSR as in the case of sending the BSR by the network device.

In a seventh aspect, an embodiment of the present application provides a user equipment terminal, including a transceiver, a processor, and a memory; the memory is configured to store a computer program code, where the computer program code includes a computer instruction, and the processor invokes the computer instruction to enable the user equipment to execute the data transmission method provided in any one implementation manner of the first aspect to the third aspect and the first aspect to the third aspect of the embodiments of the present application.

In an eighth aspect, an embodiment of the present application provides a network device, including a transceiver, a processor, and a memory; the memory is configured to store a computer program code, where the computer program code includes computer instructions, and the processor invokes the computer instructions to cause the network device to execute the data transmission method provided in any one of the fourth aspect to the sixth aspect of the embodiments of the present application and the implementation manners of the fourth aspect to the sixth aspect.

In a ninth aspect, the present application provides a computer storage medium, where a computer program is stored, where the computer program includes program instructions, and the program instructions are used, when executed by a processor, to execute the data transmission method provided in any one implementation manner of the first aspect to the sixth aspect and the first aspect to the sixth aspect of the present application.

In a tenth aspect, an embodiment of the present application provides a computer program product, which, when run on a communication device, causes the communication device to execute the data transmission method provided in any one of the implementation manners of the first aspect to the sixth aspect and the first aspect to the sixth aspect of the present application.

In an eleventh aspect, an embodiment of the present application provides an electronic device, where the electronic device includes a device or a method for performing the method or the method described in any embodiment of the present application. The electronic device is, for example, a chip.

Drawings

The drawings used in the embodiments of the present application are described below.

Fig. 1 is a schematic architecture diagram of a communication system according to an embodiment of the present application;

fig. 2 is a schematic diagram of the architecture of the communication protocol stack of the user plane of a new radio access NR;

fig. 3 is an architectural diagram of the communication protocol stack of the control plane of an NR;

FIG. 4 is a diagram illustrating a transition of a radio resource control RRC state of a user equipment UE;

fig. 5-8 are schematic flow diagrams of some packet data transmission SDTs provided by embodiments of the present application;

fig. 9 is a schematic diagram of a data radio bearer DRB according to an embodiment of the present application;

10-18 are flow diagrams of some data transmission methods provided by embodiments of the present application;

fig. 19 to fig. 20 are schematic flowcharts of some acquiring capability information of a UE according to embodiments of the present application.

Detailed Description

The embodiments of the present application will be described below with reference to the drawings.

In this embodiment of the present application, the network device may be a device for sending or receiving information, and optionally, the network device is an access network device. Such as but not limited to: a base station, a User Equipment (UE), a wireless Access Point (AP), a Transmission and Reception Point (TRP), a relay device, or other network devices having the function of the base station. The base station is a device deployed in a Radio Access Network (RAN) and configured to provide a wireless communication function. The names of the base stations may be different in different wireless access systems. Such as, but not limited to, Base Transceiver Stations (BTS) in global system for mobile communications (GSM) or Code Division Multiple Access (CDMA), Node B (NB) in Wideband Code Division Multiple Access (WCDMA), evolved node B (eNodeB) in Long Term Evolution (LTE), and also fifth generation mobile communication technology (5G), i.e., the next generation base station (G node B, gb) in new radio access (NR), or base stations in other future network systems.

In this embodiment, the terminal may be a device having a wireless communication function, and optionally, the terminal is a UE. In some scenarios, a terminal may also be referred to as a mobile station, an access terminal, a user agent, and/or the like. For example, the terminal is in the form of a handheld device, a wearable device, a computing device, a portable device, or a vehicle-mounted device. For example, the terminal is specifically a device such as a cellular phone, a smart phone, smart glasses, a laptop, a personal digital assistant, or a cordless phone. The following embodiments take a terminal as an example for a UE.

In the present application, the UE obtains the data packet, may generate the data packet for the UE, and may also receive the data packet from other devices for the UE.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a communication system according to an embodiment of the present disclosure. The communication system may be, but is not limited to, GSM, CDMA, Wideband Code Division Multiple Access (WCDMA), time-division code division multiple access (TD-SCDMA), Universal Mobile Telecommunications System (UMTS), LTE, NR, or other future network systems.

As shown in fig. 1, the communication system may include a core network 110, a network device 120, and a UE 130. Where core network 110 may be coupled to at least one network device 120, network device 120 may provide wireless communication services for at least one UE130, and UE130 may be coupled to at least one network device 120 via an air interface. The core network 110 is a key control node in the communication system, and is mainly responsible for signaling processing functions, such as but not limited to functions for implementing access control, mobility management, session management, and the like. Optionally, network device 120 is a base station. At least one base station may constitute a RAN node. In NR, the Core network 110 may be referred to as a 5G Core (5G Core, 5GC)110, and the network device 120 may be referred to as a gNB 120. The NR-RAN node may include at least one gNB120 connected to the 5GC110 through an NG interface, and at least one gNB120 of the NR-RAN node may be connected and communicate through an Xn-C interface. UE130 may connect to gNB120 over a Uu interface.

Core network 110 may send downlink data to UE130 through network device 120, and UE130 may also send uplink data to core network 110 through connected network device 120. It should be noted that the forms and numbers of the core network 110, the network device 120, and the UE130 shown in fig. 1 are only examples, and the embodiment of the present application does not limit this.

For convenience of understanding, in the embodiments of the present application, LTE and/or NR are mainly used as an applied communication system, and a network device is used as a base station for example. The LTE is mature, and descriptions such as the communication protocol stack of the LTE are not described in detail. Next, the communication protocol stack of NR will be mainly explained.

Referring to fig. 2, fig. 2 is a schematic diagram of an NR user plane protocol stack. The user plane protocol stack may include a Physical (PHY) layer, a Media Access Control (MAC) layer, a Radio Link Control (RLC) layer, a Packet Data Convergence Protocol (PDCP) layer, and a Service Data Adaptation Protocol (SDAP) layer.

Referring to fig. 3, fig. 3 is a schematic diagram of an NR control plane protocol stack. The control plane protocol stack may include a PHY layer, a MAC layer, an RLC layer, a PDCP layer, a Radio Resource Control (RRC) layer, a non-access stratum (NAS).

As shown in fig. 2 and 3, the MAC layer may serve a higher layer (e.g., RLC layer) via a Logical Channel (LCH). The logical channels may be classified into a control channel for transmitting control information in a control plane and a traffic channel for transmitting user data in a user plane according to the type of transmission information. The control channel may include, but is not limited to, a Common Control Channel (CCCH) and a Dedicated Control Channel (DCCH). The traffic channel may include, but is not limited to, a Dedicated Traffic Channel (DTCH). The CCCH may exist all the time and may be used by UEs that do not have an RRC connection with the RAN node to transmit information. The DCCH may be used for transmission of dedicated control information between the UE and the RAN node. The DTCH may be used for the transmission of user data between the UE and the RAN node. Generally, DCCH and DTCH do not always exist, but after a base station connected to a UE restores a UE context (UE context), the DCCH and DTCH can be used for communication between the UE and the base station. The UE context includes, but is not limited to, an identifier of a terminal, a Radio Bearer (RB) related configuration, a security encryption related configuration, a quality of service related configuration, and the like. When the base station configures the logical channel for the UE, the base station may simultaneously indicate a Logical Channel Group (LCG) to which the logical channel belongs, that is, the base station knows which LCG each logical channel belongs.

The RB may be a connection format set between the UE and the RAN node and may include the relevant configuration of physical channels, transport channels, and logical channels. The RB may be divided into a Signaling Radio Bearer (SRB) for transmitting control information in the control plane and a Data Radio Bearer (DRB) for transmitting user data in the user plane. A DRB may include an entity of a PDCP layer (PDCP entity), an entity of an RLC layer (RLC entity), and a logical channel.

As shown in fig. 3, the RRC layer may be used to transmit RRC messages between the UE and the base station. For example, but not limited to, an RRC resume request (RRCResumeRequest) in the NR may be used for the UE to request resumption of the already suspended RRC connection, thereby transmitting data with the base station. The RRC layer belongs to an Access Stratum (AS). For the RRC layer, there are currently three RRC states of the UE, which are an RRC IDLE (RRC IDLE) state, an RRC inactive (RRC INACTIVE) state, and an RRC CONNECTED (RRC CONNECTED) state. The UE performs most of the different operations in different RRC states, and the three states of the transition process may specifically refer to the example in fig. 4 below.

Compared with the user plane protocol stack of the LTE, the user plane protocol stack of the NR has an additional SDAP layer, but the architectures of other layers are consistent, and the specific description is similar and will not be repeated. The control plane protocol stack of LTE and the control plane protocol stack of NR have the same architecture, and the specific description of each layer is similar and will not be described again.

It is to be understood that the architecture and the service scenario described in this application are for more clearly illustrating the technical solution of this application, and do not constitute a limitation to the technical solution provided in this application, and it is known to those skilled in the art that as the network architecture evolves and a new service scenario appears, the technical solution provided in this application is also applicable to similar technical problems.

Referring to fig. 4, fig. 4 is a diagram illustrating RRC state transition of a UE. Specifically, when the UE is in the RRC CONNECTED state, an RRC connection exists between the UE and the base station, so that information such as user data can be transmitted and received. The NR-RAN and the UE may keep UE context at the AS layer, the NG-RAN knowing the cell to which the UE belongs. The UE may enter the RRC IDLE state from the RRC CONNECTED state at the direction of the base station. When the UE is in the RRC IDLE state, there is no RRC connection between the UE and the base station. For example, after the UE receives the RRC connection release message sent by the base station, the RRC connection between the UE and the base station may be stopped, and the RAN node may delete the UE context of the UE. When the UE is in an RRC IDLE state, the UE may perform selection of a Public Land Mobile Network (PLMN), cell reselection, system information acquisition, called Paging (Paging) initiated by a 5GC, Discontinuous Reception (DRX) configured by a NAS layer for core network Paging, and the like.

RRC INACTIVE state is the newly added RRC state in NR. Generally, for a UE with infrequent data transmission, the base station usually keeps the UE in state RRC INACTIVE. The UE may also enter RRC INACTIVE state from RRC CONNECTED state at the direction of the base station. For example, after the UE receives an RRC connection release message with a suspend indication sent by the base station, the RRC connection between the UE and the base station may be suspended, but at least one RAN node retains the UE context of the UE. When the UE is in the RRC INACTIVE state, the UE may perform Public Land Mobile Network (PLMN) selection, cell reselection, system information acquisition, called Paging (Paging) initiated by the NG-RAN, RAN-based Notification Area (RNA) managed by the NG-RAN, DRX configured by the NG-RAN for RAN Paging, and the like. The NR-RAN and UE may retain UE context at AS layer, RNA where the UE is known to the NG-RAN.

It is to be appreciated that the UE enters the RRC CONNECTED state from the RRC INACTIVE state faster than it enters the RRC CONNECTED state from the RRC IDLE state. The UE may also enter the RRC IDLE state from the RRC INACTIVE state under the instruction of the base station, and the specific procedure is similar to the above-mentioned entering of the RRC IDLE state from the RRC CONNECTED state.

To enter the RRC CONNECTED state, the UE in the RRC IDLE state or RRC INACTIVE state may perform Random Access (RA), or perform RA in response to a paging message of the base station. The RA may include 4-step random access (4-step-RA) and 2-step random access (2-step-RA). When the UE is not configured with non-contention random access (contention free random access), the UE may initiate a 4-step-RA or a 2-step-RA based on a currently measured Reference Signal Received Power (RSRP) and a relative size of a preset RSRP threshold. For example, the UE may initiate a 2step-RA when the currently measured RSRP is greater than or equal to a preset RSRP threshold. When the currently measured RSRP is less than the preset RSRP threshold, the UE may initiate a 4 step-RA. Wherein, the message sent by the UE to the base station in the third step of 4step-RA may be referred to as message 3, which is abbreviated as msg 3. The message sent by the UE to the base station in the first step of the 2step-RA may be referred to as message a, msgA for short.

Wherein, the msg3 or msgA may comprise RRC message. The RRC messages may be different when the UE is in different RRC states and in different traffic scenarios. For example, if there is a large amount of data transmitted to the base station by the UE in RRC INACTIVE state, the msg3 may include an RRCResumeRequest message to request to resume the RRC connection that has been suspended and to enter an RRC CONNECTED state to transmit data with the base station. It should be noted that, the base station does not only indicate the RRC state of the UE according to the message (e.g., msg3 or msgA) sent by the UE, but also needs to determine the indicated RRC state of the UE by comprehensively considering network conditions such as network congestion, resource scheduling, resource occupation, and the like.

If the UE in the RRC CONNECTED state wants to send uplink data to the network device, it needs to maintain uplink synchronization (TA). If the UE in the RRC CONNECTED state does not obtain uplink synchronization, the UE may initiate an RA to the network device. Wherein, when the Timing Advance Timer (TAT) of the UE keeps running, the UE keeps uplink synchronization. And when the TAT of the UE is overtime, the uplink synchronization of the UE is invalid.

When there is no uplink resource but there is uplink data to be sent to the base station, the UE in the RRC CONNECTED state may trigger a Buffer Status Reporting (BSR) to request the base station to schedule the uplink resource. The BSR may be used to indicate the amount of data currently pending for transmission in a data buffer (buffer) of the UE. The data amount may be different at different times, for example, the UE is a smart phone, and the user may send a message to other users through a social application installed on the UE, but types and numbers of messages sent by the user at different times may be different, sometimes the sent message may be only one text message, and sometimes the sent message may include multiple videos. The size of the BSR that the UE transmits to the base station at different times may also be different. The resource for the UE to send the BSR to the base station (BSR resource for short) may be dynamically scheduled by the base station to the UE.

When the UE also has no BSR resource, the UE may trigger a Scheduling Request (SR). The SR is used for the UE in the RRC CONNECTED state to request the base station to schedule the uplink resource. Different from the BSR resource that is dynamically scheduled by the base station to the UE, the resource for transmitting the SR (SR resource for short) is a series of Physical Uplink Control Channel (PUCCH) resources that are pre-configured by the base station to the UE. Different UE have different configured SR resources, and the base station can determine the corresponding UE according to the SR resources used when the UE reports the SR. Also, unlike the size of the BSR, which varies, the size of the SR is generally a fixed 1 bit (bit). The SR is used to indicate that the UE has data to transmit, but cannot indicate a specific amount of data.

When the UE does not have BSR resources but SR resources, the UE may report the SR to the network device on the SR resources, so that the base station schedules the uplink resources to the UE. The time for reporting the SR needs to be within a period configured by the base station for the UE (referred to as an SR period for short). Unless the UE can complete the transmission of data in the buffer of the UE through the uplink resource, the UE may transmit a BSR through the uplink resource instead of sending a newly obtained data packet or a data packet with a higher priority. That is, when the uplink resources are limited, the BSR has a higher priority than the packet.

The network device may configure at least one logical channel for each set of SR configuration configured for the UE, and each logical channel may be mapped with at least one set of SR configuration. Each set of SR configurations may include SR configuration (SchedulingRequestConfig) information and SR resource configuration (SchedulingRequestResourceConfig) information. Wherein, the schedulingRequestConfig includes fields such as: SR configuration Identity (ID) (schedulingRequestId), SR transmission prohibited time (SR-ProhibitTime), SR retransmission maximum number of times (SR-TransMax). The unit of SR-ProhibitTime is millisecond, the UE is forbidden to start timing after reporting the SR, and when the timing duration exceeds SR-ProhibitTime, the UE can report the SR again. And SR-TransMax represents the maximum number of times that the UE can retransmit the SR, the UE can report the SR again under the condition that the forbidden timer is overtime, and if the number of times that the UE reports the SR again is equal to SR-TransMax, the UE can initiate random access.

The SchedulingRequestResourceConfig includes fields such as: SR resource (resource), SR resource id (schedulingrequestid), SR configuration id (schedulingrequestid) using the SR resource, SR period (periodicityAndOffset), and priority (phy-priority index) of the SR resource.

However, if the UE does not have SR resources, the UE needs to initiate an RA to the base station to request scheduling of resources. Or when the SR configured by the base station fails (e.g., TAT times out), the UE needs to initiate an RA to the base station, so as to acquire uplink synchronization.

It can be understood that, in general, if there is uplink data to be sent to the base station by the UE in the RRC IDLE state or RRC INACTIVE state, or the UE in the RRC IDLE state or RRC INACTIVE state receives a Paging (Paging) message sent by the base station, where the Paging message is used for indicating that there is downlink data to be sent to the UE by the base station, the UE needs to perform a random access procedure and enter an RRC CONNECTED state, and transmit data with the base station in the RRC CONNECTED state. However, the above method is more suitable for a case where the amount of data transmitted between the UE and the base station is large. If the transmitted data packet is very small, the data packet can be called small packet data (small data), and signaling required in the process of switching the state of the UE is even larger than the small packet data, thereby causing unnecessary power consumption and signaling overhead of the UE.

In this embodiment of the application, the packet data may be, but is not limited to, a data packet whose data amount is smaller than a preset threshold (for example, the size of a transmission block indicated by the base station), a data packet whose data label is packet data, a data packet whose data type belongs to packet data, and the like. The data packet of the non-small packet data may be referred to as a large packet data, and may be, but is not limited to, a data packet whose data amount is greater than or equal to a preset threshold, a data packet whose data tag is a large packet data, a data packet whose data type belongs to a large packet data, and the like. Wherein, the data tag and/or the data type may be negotiated by the UE and the network device. For example, the data tag may include a large packet of data and a small packet of data. For example, data of which the data type is a heartbeat packet is packet data, and data of which the data type is a file, video or audio is packet data. The packet data is, for example, an instant messaging message, a heartbeat packet, periodic data, and the like.

In the embodiment of the application, the UE in the RRC IDLE state or RRC INACTIVE state (which may be collectively referred to as a non-CONNECTED state in the following description) may transmit the small data during the RA procedure, without entering the RRC CONNECTED state and then transmitting the small data. The transmission process may be referred to as RA-based small packet data transmission (SDT). RA may include 4-step-RA and 2-step-RA, and accordingly, SDT may also include 4-step-RA based SDT (4-step-SDT for short) and 2-step-RA based SDT (2-step-SDT for short). Examples of 4step-SDT are specifically referred to below in FIG. 5 and FIG. 6, and examples of 2step-SDT are specifically referred to below in FIG. 7 and FIG. 8.

It should be noted that the DRBs configured by the base station for the UE may include DRBs for carrying small packet data (abbreviated as SDT DRBs) and DRBs for carrying large packet data (abbreviated as non-SDT DRBs). The UE can initiate the SDT only when the small packet data carried by the SDT DRB arrives, and the UE cannot initiate the SDT if the large packet data carried by the non-SDT DRB arrives. The DRBs described in fig. 5-8 below are all SDT DRBs. When the UE initiates the SDT, the UE context needs to be restored, which may specifically include the SDT DRB, and optionally the non-SDT DRB.

Referring to fig. 5 and fig. 6, fig. 5 is a schematic flow chart of a 4step-SDT under a control plane according to an embodiment of the present application, and fig. 6 is a schematic flow chart of a 4step-SDT under a user plane according to an embodiment of the present application.

As shown in fig. 5, the SDT shown in fig. 5 includes, but is not limited to, the following steps:

s101: the UE sends a random access preamble (random access preamble) to the base station.

S102: in response to the random access preamble, the base station sends a Random Access Response (RAR) to the UE.

S103: based on the resource scheduled by the RAR, the UE sends an RRC request message carrying uplink packet data to the base station.

S104: and the base station sends uplink packet data to the core network.

S105: the base station sends an RRC response message to the UE.

Specifically, when the UE has uplink packet data to send to the base station, the UE may initiate a 4 step-RA. After sending the random access preamble to the base station, the UE may monitor a Physical Downlink Control Channel (PDCCH) within a RAR time window to receive the RAR sent by the base station. If the UE does not receive the RAR sent by the base station within the RAR time window, the UE may determine that RA fails this time. The RAR is configured to schedule an uplink grant (UL grant) for the UE, so that the UE can send msg3 (i.e., the RRC request message) based on the resource scheduled by the RAR, where msg3 carries uplink packet data. For example, the msg3 sent by the UE may be an RRC data early transfer request (RRCEarlyDataRequest) message.

The RRC request messages may be different for UEs in different RRC states and in different traffic scenarios. For example, the msg3 sent by the UE in the RRC IDLE state (optionally, the UE may store UE context such as configuration information for obtaining a key for encrypting uplink packet data at this time) may be an RRC connection request (RRCConnectionRequest) message, an RRC connection recovery request (RRCConnectionResumeRequest) message, an RRCEarlyDataRequest message, an rrcresumererequest message, an RRC setup request (RRCSetupRequest) message, or other RRC messages having the same function but not standardized by the third generation partnership project (3 GPP). The msg3 sent by the UE in state RRC INACTIVE may also be an RRCConnectionRequest message, an rrcconnectionresumerrequest message, an RRCEarlyDataRequest message, an rrcresumrequest message, an RRCSetupRequest message, or other RRC messages with the same functionality but not standardized by 3 GPP.

The uplink packet data can be carried in msg3, carried by SRB and transmitted on CCCH. For example, the uplink packet data may be carried in an NAS layer related IE (such as a dedicated information NAS (dedicatedinfonas) IE) included in the RRCEarlyDataRequest message, and transmitted on the CCCH.

Accordingly, the base station can transmit the uplink packet data to the core network through the msg3 carrying the uplink packet data. For example, the base station may send uplink packet data to the core network by forwarding the NAS layer related IE contained in msg 3. The base station may also send a contention resolution (contention resolution) message to the UE. The content resolution message is actually a content resolution MAC Control Element (CE), and is used to indicate that the UE is currently successfully randomly accessed.

Finally, the base station may send an RRC response message to the UE. In some embodiments, before S105, if the core network has downlink packet data to send to the UE, the core network may send the downlink packet data to the base station. Then, in S105, the base station may send the downlink packet data to the UE through an RRC response message carrying the downlink packet data. Wherein, the downlink packet data can be carried in the RRC response message and transmitted on the CCCH. For example, the RRC response message is an RRC data early transmission complete (RRCEarlyDataComplete) message, and the downlink packet data may be carried in an IE related to the NAS layer included in the RRCEarlyDataComplete message and transmitted on the CCCH.

And if the UE does not receive the RRC response message, the uplink packet data transmission is considered to be unsuccessful. If the UE receives the RRC response message sent by the base station, it can obtain whether the uplink packet data is successfully transmitted according to the RRC response message. For example, if the RRC response message sent by the base station is an RRCEarlyDataComplete message or an RRC connection setup (RRCConnectionSetup) message, the UE may obtain that the uplink packet data transmission is successful according to the RRC response message.

In some embodiments, if the core network does not have a need for further data transmission, the RRC response message may be used to indicate that the UE has successful uplink packet data transmission and indicate that the UE remains in the current non-connected state. For example, the RRC response message is an RRCEarlyDataComplete message, an RRC connection release (RRCConnectionRelease) message, an RRC release (rrcreelease) message, or other RRC messages having the same function but not standardized by 3 GPP. The UE can obtain that the uplink packet data transmission is successful according to the RRC response message.

In some embodiments, if the core network has a need for further data transmission, and the core network may trigger the indication procedure of connection establishment, the RRC response message may be used to indicate that the UE enters the RRC CONNECTED state. For example, the RRC response message is an RRCConnectionSetup message, an RRC connection recovery (rrcconnectionsesume) message, an RRC setup (RRCSetup) message, an RRC recovery (rrcreesume) message, or other RRC messages having the same function but not standardized by 3 GPP. The UE can obtain the successful transmission of the uplink packet data according to the RRC response message.

In some embodiments, the RRC response message is used to indicate that the UE failed to transmit uplink packet data and indicate that the UE remains in a current non-connected state. For example, the RRC response message is an RRC connection reject (RRCConnectionReject) message, an RRC reject (RRCReject) message, or other RRC messages having the same function but not standardized by 3 GPP. The UE may obtain the uplink packet data transmission failure according to the RRC response message.

As shown in fig. 6, the SDT shown in fig. 6 includes, but is not limited to, the following steps:

s201: and the UE sends random access preamble to the base station.

S202: and responding to the random access preamble, and sending the RAR to the UE by the base station.

S203: based on the resources scheduled by the RAR, the UE sends uplink packet data and an RRC request message to the base station.

S204: and the base station recovers the context of the UE and sends uplink packet data to the core network.

S205: the base station sends an RRC response message to the UE.

Specifically, when there is uplink packet data to be sent to the base station, the UE may initiate a 4-step-RA, and in a third step of the 4-step-RA, send msg3 (i.e., RRC request message) and uplink packet data to the base station. For example, the msg3 sent by the UE may be a rrcconnectionresumerrequest message or a rrcresumererequest message. The RRC request message may be different when the UE is in different RRC states and in different service scenarios, which may specifically refer to an example of the RRC request message in fig. 5, and is not described herein again.

The uplink packet data may be carried by a DRB and sent on a logical channel DTCH, the RRC request message may be carried by an SRB and sent on a logical channel CCCH, and the two are multiplexed by the MAC layer into one MAC Protocol Data Unit (PDU) and sent to the base station (the process of multiplexing into one MAC PDU may be referred to as a packet). That is, after receiving the RAR, the UE performs packet packing before sending msg3 and uplink packet data to the base station. And, the data actually transmitted by the UE in S203 is the MAC PDU.

Accordingly, the base station may restore the UE context and send the received uplink packet data to the core network. The base station may also send a content resolution message (i.e., content resolution MAC CE) to the UE to indicate that the UE currently has a successful random access.

Finally, the base station may send an RRC response message to the UE. In some embodiments, before S205, if the core network has downlink packet data to send to the UE, the core network may send the downlink packet data to the base station. Then, in S205, the base station may transmit the downlink packet data to the UE together when transmitting the RRC response message. Wherein, the downlink packet data can be transmitted on DTCH and multiplexed with RRC response message transmitted on DCCH.

And if the UE does not receive the RRC response message, the uplink packet data transmission is considered to be unsuccessful. If the UE receives the RRC response message sent by the base station, the UE may obtain whether the uplink packet data is successfully transmitted according to the RRC response message. For example, the RRC response message sent by the base station may be an RRCConnectionRelease message, an rrcconnectionresponse message, an RRCConnectionSetup message, an rrcelease message, an rrcreesume message, or an RRCSetup message, and the UE may obtain that the uplink packet data transmission is successful according to the RRC response message. For the description of the RRC response message, reference may be specifically made to the description of the RRC response message in fig. 5, which is not described herein again.

Fig. 5 and fig. 6 illustrate an example where the UE performs S101 and/or S201 when there is uplink packet data to be sent to the base station, that is, the UE actively initiates SDT. However, in a specific implementation, there is also a case where the UE passively initiates a transmission process of the packet data under the instruction of the base station, for example, a terminal terminated (MT) EDT (MT-EDT for short) in LTE. The transmission process in this case is similar to the transmission process shown in fig. 5 and 6, with the following differences:

before S101 or S201, when the core network has downlink packet data to send to the UE, the core network may send a paging message to the base station. Optionally, the paging message may carry data size information of downlink packet data. Accordingly, the base station may send a paging message to the UE to cause the UE to initiate a 4 step-RA. For example, the base station may trigger the MT-EDT according to the paging message and send a paging message carrying the MT-EDT indication to the UE, so that the UE triggers the MO-EDT for the MT-EDT. Among them, the difference from the process shown in fig. 5 is: in S103, the RRC request message sent by the UE to the base station may not carry uplink packet data, and optionally, may also carry reason information for triggering MT-EDT. Accordingly, S104 may be changed to receive downlink packet data sent by the core network. In S105, the RRC response message sent by the base station to the UE carries the downlink packet data. The difference from the process shown in fig. 6 is that: in S203, the UE may only send the RRC request message to the base station, and does not send the uplink packet data, and optionally, may also carry reason information for triggering the MT-EDT. Accordingly, S204 may be changed to receive downlink packet data sent by the core network for the base station. S205 may be modified to transmit the RRC response message and the downlink packet data to the UE.

Referring to fig. 7 and 8, fig. 7 is a schematic flow chart of a sub-control plane 2step-SDT according to an embodiment of the present application, and fig. 8 is a schematic flow chart of a sub-user plane 2step-SDT according to an embodiment of the present application.

As shown in fig. 7, the SDT shown in fig. 7 includes, but is not limited to, the following steps:

s301: and the UE sends random access preamble and RRC request message carrying uplink packet data to the base station.

S302: and the base station sends the uplink packet data to the core network.

S303: the base station sends an RRC response message to the UE.

Specifically, when the UE has uplink packet data to send to the base station, the UE may initiate a 2-step-RA, and send a random access preamble and msgA carrying the uplink packet data (i.e., the RRC request message) to the base station in a first step of the 2-step-RA. For example, the msgA sent by the UE may be a RRCResumeRequest message. The RRC request message may be different when the UE is in different RRC states and in different service scenarios, which may specifically refer to the example of the RRC request message in fig. 5 and is not described herein again.

The RRC request message carrying the uplink packet data may be carried in a Physical Uplink Shared Channel (PUSCH) load and may be transmitted on the CCCH.

Correspondingly, the base station may send the uplink packet data to the core network through the msgA, for example, the base station may send the uplink packet data to the core network by forwarding an RRCResumeRequest message carrying the uplink packet data. The base station may also send a content resolution message (i.e., content resolution MAC CE) to the UE to indicate that the UE currently has a successful random access.

Finally, the base station may send an RRC response message to the UE. In some embodiments, before S303, if the core network has downlink packet data to send to the UE, the core network may send the downlink packet data to the base station. Then, in S303, the base station may send the downlink packet data to the UE through an RRC response message carrying the downlink packet data. The downlink packet data may be carried in an RRC response message and transmitted on the CCCH.

And if the UE does not receive the RRC response message, the uplink packet data transmission is considered to be unsuccessful. If the UE receives the RRC response message sent by the base station, the UE can obtain whether the transmission of the uplink packet data is successful or not according to the response message. For example, the RRC response message sent by the base station may be an rrcreelease message, an RRCSetup message, or an rrcreesume message, and the UE may obtain that the uplink packet data transmission is successful according to the RRC response message. For the description of the RRC response message, reference may be specifically made to the description of the RRC response message in fig. 5, which is not described herein again.

As shown in fig. 8, the SDT shown in fig. 8 includes, but is not limited to, the following steps:

s401: and the UE sends random access preamble, RRC request message and uplink packet data to the base station.

S402: and the base station recovers the context of the UE and sends uplink packet data to the core network.

S403: the base station sends an RRC response message to the UE.

Specifically, the process of S401 is similar to S301 of fig. 7, except that: in S401, the uplink packet data is not carried in the RRC request message, but is transmitted together with the RRC request message. The RRC request message may be different when the UE is in different RRC states and in different service scenarios, which may specifically refer to an example of the RRC request message in fig. 5, and is not described herein again.

In S401, the RRC request message and the uplink packet data may be carried in a PUSCH payload. And, the uplink packet data can be carried by DRB and sent on the logical channel DTCH, the RRC request message can be carried by SRB and sent on the logical channel CCCH, and the two are multiplexed into one MAC PDU (i.e. packet) by the MAC layer. Then, in S401, the RRC request message and the uplink packet data sent by the UE to the base station are actually MAC PDUs obtained by the above-mentioned grouping.

Finally, the base station may send an RRC response message to the UE. In some embodiments, before S403, if the core network has downlink packet data to send to the UE, the core network may send the downlink packet data to the base station. Then, in S403, the base station may transmit the downlink packet data to the UE together when transmitting the RRC response message. Wherein, the downlink packet data can be transmitted on DTCH and multiplexed with RRC response message transmitted on DCCH.

And if the UE does not receive the RRC response message, the uplink packet data transmission is considered to be unsuccessful. If the UE receives the RRC response message sent by the base station, the UE may obtain whether the uplink packet data is successfully transmitted according to the RRC response message. For example, the RRC response message sent by the base station may be an rrcreelease message, an RRCSetup message, or an RRCResume message, and the UE may obtain that the uplink packet data transmission is successful according to the RRC response message. For the description of the RRC response message, reference may be specifically made to the description of the RRC response message in fig. 5, which is not described herein again.

Fig. 7 and 8 illustrate the case where the UE performs S301 and/or S401 when there is uplink packet data to be sent to the base station, that is, the UE actively initiates a transmission process of the packet data. However, in a specific implementation, there is also a case where the UE passively initiates a transmission process of the packet data under the instruction of the base station. The transmission process in this case is similar to the transmission process shown in fig. 7 and 8, with the following differences:

before S301 or S401, when the core network has downlink packet data to send to the UE, the core network may send a paging message to the base station. Optionally, the paging message may carry data amount information of downlink packet data. Accordingly, the base station may send a paging message to the UE to cause the UE to initiate a 2 step-RA. Among them, the difference from the process shown in fig. 7 is: in S301, the RRC request message sent by the UE to the base station may not carry uplink packet data. The difference from the process shown in fig. 8 is that: in S401, the UE may only send random access preamble and RRC request message to the base station, and does not send uplink packet data. Accordingly, S302 and S402 may be changed to receive downlink packet data sent by the core network for the base station. In S303, the RRC response message sent by the base station to the UE carries the downlink packet data. In S403, the base station sends an RRC response message and downlink packet data to the UE.

Not limited to the RA-based SDT listed above, in a specific implementation, the SDT may also be implemented based on configured resources (configured graphs). That is, the UE in the non-connected state may also send the RRC request message and the uplink packet data to the base station based on the preconfigured uplink resource, or send the RRC request message to the base station and receive the downlink packet data sent by the base station based on the preconfigured uplink resource. The preconfigured uplink resource is, for example, but not limited to, a Preconfigured Uplink Resource (PUR) or a configured resource Type one (CG Type 1).

It can be understood that the base station may not configure the UE with the preconfigured uplink resource, and at this time, the UE in the non-connected state can only perform the RA-based SDT. In the present application, the base station does not configure the UE with the preconfigured uplink resource as an example for explanation, and therefore the SDT in the following embodiment is actually an RA-based SDT.

When the UE and the network device perform SDT, the UE may obtain a new data packet to be transmitted. For example, after S201 and before S205 of fig. 6 above, the UE obtains a new packet. Alternatively, after S401 and before S403 of the above fig. 8, the UE obtains a new packet. At this time, the UE may trigger reporting of the BSR to the network device, but there may be no BSR resource, and then the UE may trigger reporting of the SR to the network device. However, the network device will typically only allocate SR resources to UEs in RRC CONNECTED state, so a UE that is in SDT can only initiate a new RA or SDT to request scheduling resources from the network device. For example, when the new data packet is small packet data, the UE may reinitiate a new SDT, and when the new data packet is large packet data, the UE may reinitiate a new RA.

When the UE initiates a new RA or SDT, it may wait for the end of the currently performed SDT to initiate the new RA or SDT, but the transmission delay of the new data packet is relatively long. Alternatively, the UE may stop the currently ongoing SDT and directly initiate a new RA or SDT, but then the latency of the currently transmitted packet data may be large. Or, the UE may not stop the currently performed SDT and directly initiate a new RA or SDT, but if the new data packet is packet data, unnecessary signaling overhead may also be brought, and transmission delay of the new data packet is affected. That is, the transmission delay of the currently transmitted packet data or new data packet may be large.

The application provides a data transmission method which can be applied to a scene that UE obtains a new data packet when the UE and network equipment are carrying out SDT. The network device may configure, for the UE, an SR applied in a non-connected state, which is referred to as an inactive SR (inactive SR), and specifically may include a first SR and a second SR. When the UE obtains a new data packet, if the UE does not send the resource of the BSR, the UE can trigger the report of the inactive SR, and then the UE can report the inactive SR to the network equipment so that the network equipment can obtain the data transmission requirement of the UE. When the new data packet is packet data, the UE may send a first SR to the network device, and the network device may dynamically schedule uplink resources for the UE according to the first SR, where the uplink resources are used for the UE to send the new data packet to the network device, and the specific flow is as shown in fig. 10 and 12. When the second packet is large packet data, the UE may send a second SR to the network device, and the network device may instruct the UE to enter an RRC CONNECTED state in response to the second SR, and the UE may transmit a new packet in the RRC CONNECTED state, where the specific flow is as shown in fig. 11 and 13 below. Therefore, the UE does not need to initiate a new RA or SDT, unnecessary signaling overhead and power consumption are saved, the transmission delay of a new data packet can be reduced while the delay of currently transmitted packet data is not influenced, and the user experience is good.

The inactive SR may be used for requesting a scheduling resource from the network device by the UE in the non-connected state, and may be a PUCCH resource. The DRBs configured by the network device for the UE may include DRBs for carrying small packet data, i.e., SDT DRBs, and DRBs for carrying large packet data, i.e., non-SDT DRBs. When the UE initiates the SDT, the SDT DRB may be recovered, and optionally, the non-SDT DRB may also be recovered.

The way for the network device to configure inactive SR for the UE may be, but is not limited to, any of the following:

the first method is as follows: when the UE is in RRC CONNECTED state, the network device configures an available inactive SR for a logical channel included in the DRB of the UE, and the available inactive SR can be identified by an inactive SR ID. For example, the network device configures an available inactive SR for logical channel 1 of the UE, and the inactive SR ID of the available inactive SR is 1. And when the UE is in the RRC CONNECTED state, the network device may also configure a plurality of inactive SRs for the UE. Each inactive SR set may include an inactive SR ID. Each inactive SR set may also include schedule request config information and schedule request resource config information, as described above with reference to fig. 4.

The second method comprises the following steps: when the UE is in RRC CONNECTED state, the network device configures an available inactive SR for a logical channel included in the DRB of the UE, and the available inactive SR can be identified by an inactive SR ID. For example, the network device configures an available inactive SR for logical channel 1 of the UE, where the inactive SR ID of the available inactive SR is 1. When the UE enters the non-CONNECTED state from the RRC CONNECTED state or the UE ends the currently performed SDT procedure, the network device may further configure a plurality of inactive SRs sets for the UE through an RRC response message (e.g., an RRC delete message). Each inactive SR set may include an inactive SR ID. Each inactive SR set may also include schedule request config information and schedule request resource config information, as described above with reference to fig. 4.

The third method comprises the following steps: when the UE enters the non-CONNECTED state from the RRC CONNECTED state or the UE ends the current SDT procedure, the network device may further configure a plurality of inactive SRs for the UE through an RRC response message (e.g., an RRC release message). Each inactive SR set may include an ID of a logical channel that can use the inactive SR. Each inactive SR set may further include schedule request config information and schedule request resource config information in fig. 4 above.

In the first and second manners, the available inactive SR of the logical channel configuration included in the SDT DRB may be the first SR, and the available inactive SR of the logical channel configuration included in the non-SDT DRB may be the second SR. Therefore, after receiving the first SR, the network device may determine that the corresponding logical channel is a logical channel included in the SDT DRB, thereby determining that the data to be transmitted by the UE is packet data.

In the third mode, the first SR configured by the network device for the UE includes a logical channel ID that can use the first SR, and the ID of the logical channel that can use the first SR may be an ID of a logical channel included in the SDT DRB. The second SR configured by the network device for the UE includes an ID of a logical channel that can use the second SR, which can be an ID of a logical channel included in the non-SDT DRB.

In this application, the logical channel included in the DRB of the UE and the available inactive SR configured for the logical channel may be referred to as having a bonding relationship, or the inactive SR configured for the UE by the network device and the logical channel that can use the inactive SR may be referred to as having a bonding relationship.

After receiving the first SR, the network device may determine that the logical channel having a binding relationship with the first SR is a logical channel included in the SDT DRB, thereby determining that the data to be transmitted by the UE is packet data. After receiving the second SR, the network device may determine that the corresponding logical channel is a logical channel included in the non-SDT DRB, thereby determining that the data to be transmitted by the UE is large packet data. Examples of the configured first SR and second SR can be seen in fig. 9 below.

Referring to fig. 9, fig. 9 illustrates a diagram of a DRB resumed by a UE when the UE initiates SDT. Fig. 9 illustrates an example in which the UE recovers the SDT DRB and the non-SDT DRB when initiating the SDT, and the inactive SR configured by the network device for the UE includes a first SR and a second SR.

As shown in fig. 9, DRBs that the UE recovers when the UE initiates SDT may include DRBs 1, DRBs 2, DRBs 3, and DRBs 4. Among them, DRBs 1 and DRBs 2 are DRBs for transmitting packet data, i.e., SDT DRBs, and DRBs 3 and DRBs 4 are DRBs for transmitting large packet data, i.e., non-SDT DRBs. The DRB1 may include logical channel 1, the DRB2 may include logical channel 2, and the logical channels having a bonding relationship with the first SR may be logical channel 1 and logical channel 2. Therefore, when a new data packet obtained by the UE is packet data, i.e., the new data packet can be carried through DRBs 1 and DRBs 2, the UE may transmit a first SR to the network device. After receiving the first SR, the network device may determine that the UE has packet data to be transmitted.

Similarly, the DRB3 may include logical channel 3, the DRB3 may include logical channel 4, and the logical channels having a bonding relationship with the second SR may be logical channel 3 and logical channel 4. Therefore, when a new data packet obtained by the UE is large packet data, i.e., the new data packet is carried through the DRB3 and the DRB4, the UE may transmit a second SR to the network device. After receiving the second SR, the network device may determine that the UE has large package data to be transmitted.

In some embodiments, the UE may send the inactive SR to the network device only after determining that the configuration of the inactive SR is in effect. Alternatively, the UE may determine that the inactive SR is valid when receiving the configuration message based on the inactive SR sent by the network device. Optionally, the UE may further determine that the inactive SR is valid when receiving a first validity message sent by the network device to indicate that the inactive SR is valid after receiving the configuration message based on the inactive SR sent by the network device. The first alive message may be Downlink Control Information (DCI), for example, DCI corresponding to RAR sent by the network device or DCI corresponding to content resolution MAC CE sent by the network device. The configuration message based on the inactive SR may be an RRC response message sent by the network device before the UE performs the SDT procedure, and the description of the RRC response message may refer to the description of the RRC response message in fig. 5. For example, the configuration message is an RRCRelease message sent in an SDT procedure performed before the SDT procedure is performed by the UE, or the configuration message is an rrcresum message sent in an RA procedure performed before the RA is performed by the UE.

In some embodiments, the UE may send the inactive SR to the network device only if the UE meets the condition for reporting the inactive SR. The conditions for reporting the inactive SR by the UE include that the UE is performing an SDT procedure and that the UE keeps uplink synchronization. When the UE obtains the second data packet during the SDT process and the UE does not send BSR resources, the inactive SR reporting may be triggered. The UE may send an inactive SR when the UE maintains uplink synchronization. For example, the UE is performing an SDT procedure, but the UE does not have a TA at this time, and then reports an inactive SR to the network device after the UE completes contention resolution and the TAT runs. Or, the UE is performing the SDT procedure, and the current TA of the UE is valid, that is, the TAT is running, and the TA may be obtained by the UE in an RA procedure or an SDT procedure before the SDT procedure, and then the UE may directly report an inactive SR to the network device.

It should be noted that the SDT procedure performed by the UE may include a start of the SDT procedure and an end of the SDT procedure. The UE may send random access preamble to the network device to indicate the start of the SDT procedure, or the UE may send msg3 or msgA to the network device to indicate the start of the SDT procedure. For example, the UE performing S201 or S203 of fig. 6 above indicates the start of the SDT procedure, or the UE performing S401 of fig. 8 above indicates the start of the SDT procedure. It may be that the UE receives the RRC response message sent by the network device to indicate that the SDT procedure is ended, for example, the UE performs S205 of fig. 6 to indicate that the SDT procedure is ended, or the UE performs S403 of fig. 8 to indicate that the SDT procedure is ended.

The present application takes as an example that when the UE sends an inactive SR to the network device, the configuration of the inactive SR is valid and the condition for reporting the inactive SR is satisfied.

Next, a data transmission method in the present application will be described based on some embodiments shown in fig. 1 to 8. The following embodiments take the transmission process of the uplink packet data under the user plane protocol stack as an example for description.

First, a data transmission method when the ongoing SDT of the UE is 4step-SDT will be described.

Referring to fig. 10, fig. 10 is a schematic flowchart of a data transmission method according to an embodiment of the present application. The method may be applied to the communication system shown in fig. 1, and the network device and the UE in the method may be the network device 120 and the UE130 shown in fig. 1. Fig. 10 illustrates an example in which the second packet is packet data. The method includes, but is not limited to, the steps of:

s501: the UE obtains a first data packet.

Specifically, when the first data packet obtained by the UE is the packet data, the UE initiates 4step-SDT, that is, executes S502.

S502: and the UE sends random access preamble to the network equipment.

S503: in response to the random access preamble, the network device sends a RAR to the UE.

S504: based on the resources scheduled by the RAR, the UE sends a first data packet and an RRC request message to the network equipment.

S505: the network device restores the UE context and sends a first data packet to the core network.

Specifically, S502-S505 are identical to S201-S204 of fig. 6, and are not described again.

S506: the network device sends a content resolution message to the UE.

Specifically, the network device sends a content resolution message (i.e., content resolution MAC CE) to the UE to indicate that the UE's current SDT is successful.

The order of S505 and S506 is not limited.

S507: the UE obtains the second data packet.

S508: and when the second data packet is packet data, the UE sends a first SR to the network equipment.

Specifically, the network device may configure the first SR for the UE before S501, that is, configure the binding relationship between the first SR and the logical channel included in the SDT DRB, so that after receiving the first SR, the network device may determine that the UE has the packet data to be transmitted. Specifically, if the second data packet newly obtained by the UE is the packet data carried by the recovered SDT DRB during the 4step-SDT procedure, the UE may trigger reporting of the BSR indicating the packet data carried by the SDT DRB. When the UE does not report the BSR resource of the BSR, the UE may trigger reporting of the first SR, and then the UE may send the first SR to the network device.

In some embodiments, the UE may obtain the second data packet before packetizing the first data packet and the RRC request message (i.e., multiplexing the first data packet and the RRC request message into one MAC PDU at the MAC layer). That is, S507 is after S501 and before S504, and the order of S507 and S502 and S503 is not limited. For example, if the currently performed SDT is the SDT shown in fig. 6, the UE may obtain a new second packet after S201 and before S203 of fig. 6.

Exemplarily, the UE no BSR resource may be: the resource scheduled by the RAR is greater than or equal to the sum of the resources for transmitting the third data packet and the RRC request message, but less than the sum of the resources for transmitting the third data packet, the RRC request message and the first BSR. I.e., resources where the UE does not transmit the first BSR. The third data packet may be a data packet with a higher priority in the first data packet and the second data packet, the first BSR may indicate a data amount of a fourth data packet, and the fourth data packet may be a data packet with a lower priority in the first data packet and the second data packet. Note that, in this case, the third packet is actually transmitted in S504. When the priority of the first packet is higher than or equal to the priority of the second packet, S504 transmits the first packet, and when the priority of the first packet is lower than the priority of the second packet, S504 transmits the second packet. At this time, since the uplink resource scheduled by the RAR is limited, the UE may preferentially transmit the small packet data with higher priority, instead of transmitting the BSR. It can be understood that, when the uplink resource scheduled by the network device is limited, the priority of the UE for transmitting the high-priority data packet is higher than the priority of the UE for transmitting the BSR MAC CE.

In some embodiments, the UE may obtain the second data packet after packaging the first data packet and the RRC request message, that is, S507 is after S504, and the order of S507 and S505 and S506 is not limited. For example, if the currently performed SDT is the SDT shown in fig. 6, the UE may obtain a new second packet after S203 and before S205 of fig. 6.

Exemplarily, the UE no BSR resource may be: there is no subsequent transmission (subsequent transmission) in the currently performed SDT, for example, when the UE initiates the current SDT procedure, the resource scheduled by the RAR is greater than or equal to the sum of the resources for transmitting the first data packet and the RRC request message, that is, the UE may complete the transmission of the current first data packet only by one-time msg3 transmission. Therefore, the UE only needs to send the first data packet and the RRC request message in S504, and does not need to carry the second BSR for indicating the subsequent transmission. Since the network device does not receive the second BSR sent by the UE in S504, it may be considered that the UE has no subsequent data transmission requirement after the UE completes transmission of the first data packet. Therefore, the network device will end the SDT procedure (e.g., send an RRC response message to the UE) after completing the transmission of the first data packet, resulting in no resources for the UE to send the third BSR, which may indicate the data amount of the second data packet.

S509: in response to the first SR, the network device allocates a first transmission resource for the UE.

Specifically, the network device may determine, according to the first SR, that the second data packet to be transmitted by the UE is small packet data, and thus may dynamically schedule the first transmission resource for the UE. The first transmission resource is used for the UE to send the second data packet to the network device, i.e. for the UE to perform S510.

The size of the first transmission resource dynamically scheduled by the network device for the UE may depend on the network device, for example, the network device determines the size of the first transmission resource based on the current load status. Or the resource size dynamically scheduled by the network device for the UE satisfies the resource size of the scheduling packet data specified in the SDT process. Optionally, the first transmission resource may also be larger than a resource scheduled for the small packet data specified in the currently performed SDT procedure.

S510: the UE transmits a second data packet to the network device using the first transmission resource.

S511: the network equipment sends a first response message to the UE.

Specifically, S511 is consistent with S205 of fig. 6, and the first response message is the RRC response message in fig. 5, for example, an rrcreelease message, which may specifically refer to the description of fig. 5 and is not described again.

In the method shown in fig. 10, during the SDT process between the UE and the network device, the UE obtains the second data packet, and the UE can notify the network device of the arrival of new packet data in time through the first SR. In response to the first SR, the network device may dynamically schedule the first transmission resource for the UE to cause the UE to transmit the second data packet using the first transmission resource. Therefore, the UE can continuously transmit new packet data in a non-connection state without initiating a new RA or SDT, thereby avoiding unnecessary signaling overhead and avoiding the condition that the UE enters an RRC CONNECTED state to increase power consumption. Meanwhile, the transmission delay of the second data packet can be reduced under the condition that the transmission delay of the first data packet is not influenced.

Referring to fig. 11, fig. 11 is a schematic flowchart of another data transmission method according to an embodiment of the present application. The method may be applied to the communication system shown in fig. 1, and the network device and the UE in the method may be the network device 120 and the UE130 shown in fig. 1. Fig. 11 illustrates an example in which the second packet is a large packet data. The method includes, but is not limited to, the steps of:

s601: the UE obtains a first data packet.

Specifically, when the first data packet obtained by the UE is the packet data, the UE initiates 4step-SDT, that is, executes S602.

S602: and the UE sends random access preamble to the network equipment.

S603: in response to the random access preamble, the network device sends a RAR to the UE.

S604: based on the resources scheduled by the RAR, the UE sends a first data packet and an RRC request message to the network equipment.

S605: the network device restores the UE context and sends a first data packet to the core network.

S606: the network device sends a content resolution message to the UE.

Specifically, S602-S606 are identical to S502-S506 of FIG. 10, and are not described again. The order of S605 and S606 is not limited.

S607: the UE obtains the second data packet.

S608: and when the second data packet is big packet data, the UE sends a second SR to the network equipment.

Specifically, the network device may configure the second SR for the UE before S601, that is, configure the binding relationship between the second SR and the logical channel included in the non-SDT DRB, so that after receiving the second SR, the network device may determine that the large package data to be transmitted exists. Specifically, if the second data packet newly obtained by the UE is big packet data and BSR resources of the BSR are not reported in the 4step-SDT process, the UE may trigger reporting of the second SR, and then the UE may send the second SR to the network.

In some embodiments, the UE may resume SDT DRBs and non-SDT DRBs when it initiates the 4step-SDT shown in FIG. 11. When the newly obtained second data packet is big packet data carried by the non-SDT DRB, the UE may trigger reporting of a BSR indicating the big packet data carried by the non-SDT DRB. When the UE does not report the BSR resource of the BSR, the UE may trigger reporting of the second SR, and then the UE may send the second SR to the network device.

In some embodiments, when the UE initiates 4step-SDT as shown in fig. 11, only SDT DRB may be recovered, and non-SDT DRB may not be recovered. At this time, the BSR triggered and reported by the UE may be used to indicate not only the small packet data carried by the recovered SDT DRB but also the large packet data carried by the non-recovered non-SDT DRB. Therefore, when the newly obtained second data packet is big packet data, the UE may trigger reporting of a BSR indicating big packet data carried by the non-SDT DRB. When the BSR resource of the BSR is not reported, the UE may trigger reporting of the second SR, and then the UE may send the second SR to the network device.

In some embodiments, the UE may obtain the second data packet before the first data packet and the RRC request message are packaged, that is, S607 is after S601 and before S604, and the order of S607 and S602, S603 is not limited. Exemplarily, the UE no BSR resource may be: the resource scheduled by the RAR is greater than or equal to the sum of the resources for transmitting the first data packet and the RRC request message, but less than the sum of the resources for transmitting the first data packet, the RRC request message and the third BSR, i.e. the UE does not transmit the third BSR. Wherein the third BSR may indicate an amount of data of the second packet. At this time, since the uplink resource scheduled by the RAR is limited, the UE may preferentially transmit the currently transmitted packet data, instead of transmitting the BSR.

In some embodiments, the UE may obtain the second data packet after packaging the first data packet and the RRC request message, that is, S607 is after S604, and the order of S607 and S605 and S606 is not limited. An example where the UE does not have BSR resources is as described above in S508 of fig. 10 for the example where the UE obtains the second data packet after packaging the first data packet and the RRC request message.

S609: in response to the second SR, the network device transmits a second response message to the UE.

Specifically, the network device may determine, according to the second SR, that the second data packet to be transmitted by the UE is big packet data, and thus may send the second response message to the UE. The second response message may be an RRC response message for instructing the UE to enter an RRC CONNECTED state. For example, the second response message is an rrcconnectionresponse message, an rrcreesume message, or other RRC message having the same function but not standardized by 3 GPP. The UE may enter the RRC CONNECTED state and then transmit the second packet.

In the method shown in fig. 11, during the SDT process between the UE and the network device, the UE obtains the second data packet, and the UE can notify the network device of the arrival of new big packet data in time through the second SR. In response to the second SR, the network device may instruct the UE to enter an RRC CONNECTED state to cause the UE to transmit the second packet in the RRC CONNECTED state. The UE does not need to initiate a new RA or SDT, so that transmission resources are saved, and unnecessary signaling overhead and power consumption are avoided. Meanwhile, the transmission delay of the second data packet can be reduced under the condition that the transmission delay of the first data packet is not influenced.

Next, a data transmission method when the SDT of the UE is 2step-SDT will be described.

Referring to fig. 12, fig. 12 is a schematic flowchart of another data transmission method according to an embodiment of the present application. The method may be applied to the communication system shown in fig. 1, and the network device and the UE in the method may be the network device 120 and the UE130 shown in fig. 1. Fig. 12 illustrates an example in which the second packet is a packet data. The method includes, but is not limited to, the steps of:

s701: the UE obtains a first data packet.

Specifically, when the first data packet obtained by the UE is the packet data, the UE initiates 2step-SDT, that is, executes S702.

S702: the UE sends random access preamble, RRC request message and first data packet to the network equipment.

S703: the network device restores the context of the UE and sends a first data packet to the core network.

Specifically, S702-S703 are identical to S401-S402 of fig. 8, and are not described in detail.

S704: the network device sends a content resolution message to the UE.

Specifically, the network device sends a content resolution MAC CE to the UE to indicate that the UE's current SDT is successful.

The order of S703 and S704 is not limited.

S705: the UE obtains the second data packet.

S706: and when the second data packet is packet data, the UE sends a first SR to the network equipment.

Specifically, if the second data packet newly obtained by the UE is the packet data carried by the recovered SDT DRB during the 2step-SDT procedure, the UE may trigger reporting of the BSR indicating the packet data carried by the SDT DRB. When the UE does not report the BSR resource of the BSR, the UE may trigger reporting of the first SR, and then the UE may send the first SR to the network device.

It should be noted that, after the UE obtains the second data packet and packages the first data packet and the RRC request message, for example, if the currently performed SDT is the SDT shown in fig. 8, the UE may obtain a new second data packet after S401 and before S403 in fig. 8. That is, the order of S705 and S703, S704 is not limited.

Exemplarily, the UE no BSR resource may be: there is no subsequent transmission (subsequent transmission) of the currently ongoing SDT. For example, the resource for transmitting the packet data of the SDT, which is broadcasted or preconfigured by the network device, is greater than or equal to the sum of the resources for transmitting the random access preamble, the first data packet, and the RRC request message, that is, the UE may complete transmission of the current first data packet only through one msgA transmission. Therefore, the UE only needs to send the random access preamble, the first data packet and the RRC request message in S702, and does not need to carry the second BSR. Since the network device does not receive the second BSR sent by the UE in S702, it may be considered that the UE has no subsequent data transmission requirement after the UE completes transmission of the first data packet. Therefore, the network device will end the SDT procedure (e.g., send an RRC response message to the UE) after completing the transmission of the first data packet, resulting in no resources for the UE to send the third BSR, which may indicate the data amount of the second data packet.

S707: in response to the first SR, the network device allocates a first transmission resource for the UE.

S708: the UE transmits a second data packet to the network device using the first transmission resource.

S709: the network equipment sends a first response message to the UE.

Specifically, S707-S709-is identical to S509-S511 of FIG. 10 above and will not be described in detail.

Referring to fig. 13, fig. 13 is a schematic flowchart of another data transmission method according to an embodiment of the present application. The method may be applied to the communication system shown in fig. 1, and the network device and the UE in the method may be the network device 120 and the UE130 shown in fig. 1. Fig. 13 illustrates an example in which the second packet is a large packet data. The method includes, but is not limited to, the steps of:

s801: the UE obtains a first data packet.

Specifically, when the first data packet obtained by the UE is the packet data, the UE initiates 2step-SDT, that is, executes S802.

S802: the UE sends random access preamble, RRC request message and first data packet to the network equipment.

S803: the network device restores the context of the UE and sends a first data packet to the core network.

S804: the network device sends a content resolution message to the UE.

Specifically, S802-S804 are identical to S702-S704 of FIG. 12, and are not described in detail. The order of S803 and S804 is not limited.

S805: the UE obtains the second data packet.

S806: and when the second data packet is big packet data, the UE sends a second SR to the network equipment.

Specifically, if the second data packet newly obtained by the UE is big packet data and BSR resources of BSR are not reported in the process of performing 2step-SDT, the UE may trigger reporting of the second SR, and then the UE may send the second SR to the network. The UE can recover the DRB as described in S608 in fig. 11. It should be noted that the order of S805 and S803 and S804 is not limited, where the UE obtains the second data packet and packages the first data packet and the RRC request message. The UE without BSR resource example can be seen in the description of S706 of fig. 12 above.

S807: in response to the second SR, the network device transmits a second response message to the UE.

Specifically, S807 is identical to S609 of fig. 11, and is not described again.

In a possible implementation, the network device may also configure the first SR only for the UE. If a new second data packet arrives when the UE performs SDT, the UE may trigger reporting of the BSR. But the UE has no BSR resource, the UE may trigger reporting of inactive SR. When the second data packet is packet data, the UE may send a first SR to the network device, and the network device may dynamically schedule, according to the first SR, a first transmission resource for the UE to send the second data packet to the network device, where the first transmission resource is used by the UE, and the specific flow is as shown in fig. 10 and fig. 11. When the second data packet is big packet data, since the UE does not configure the second SR, that is, does not report the resource of the second SR, the UE may initiate an RA to transmit the second data packet, and the specific flow is as shown in fig. 14 and fig. 15 below.

Fig. 14 illustrates an example of an SDT being performed by the UE being 4step-SDT, and fig. 15 illustrates an example of an SDT being performed by the UE being 2 step-SDT.

Referring to fig. 14, fig. 14 is a schematic flowchart of another data transmission method according to an embodiment of the present application. The method may be applied to the communication system shown in fig. 1, and the network device and the UE in the method may be the network device 120 and the UE130 shown in fig. 1. Fig. 14 illustrates an example in which the second packet is a large packet data. The method includes, but is not limited to, the steps of:

s901: the UE obtains a first data packet.

Specifically, when the first data packet obtained by the UE is the packet data, the UE initiates 4step-SDT, that is, executes S902.

S902: and the UE sends random access preamble to the network equipment.

S903: in response to the random access preamble, the network device sends a RAR to the UE.

S904: based on the resources scheduled by the RAR, the UE sends a first data packet and an RRC request message to the network equipment.

S905: the network device restores the UE context and sends a first data packet to the core network.

S906: the network device sends a content resolution message to the UE.

Specifically, S902-S906 are identical to S502-S506 of FIG. 10, and are not described again. The order of S905 and S906 is not limited.

S907: the UE obtains the second data packet.

S908: and when the second data packet is big packet data, the UE initiates RA.

Specifically, if the second data packet newly obtained by the UE is big packet data in the 4step-SDT process, the UE may trigger reporting of the BSR. However, when the UE does not report BSR resources of the BSR, the UE may trigger the report of inactive SR. However, the UE does not report the SR resource, so the UE may initiate an RA, thereby entering an RRC CONNECTED state to transmit the second packet. The resource for which the UE does not report the SR is, for example but not limited to: the network equipment does not configure the SR for the UE, the network equipment does not configure the inactive SR for the UE, the inactive SR configured for the UE by the network equipment is not effective, and the UE does not keep uplink synchronization.

The RA may be a 4step-RA, and the UE may send a random access preamble to the network device, and send msg3 based on the RAR sent by the network device. The RA may also be a 2step-RA, and the UE may send a random access preamble and msgA to the network device. An example of the UE having no BSR resources may be seen in the description of S608 of fig. 11 above.

In some embodiments, the UE may resume SDT DRBs and non-SDT DRBs when it initiates the 4step-SDT shown in FIG. 14. When the newly obtained second data packet is the big packet data carried by the non-SDT DRB, the UE may trigger reporting of a BSR indicating the big packet data carried by the non-SDT DRB.

In some embodiments, when the UE initiates 4step-SDT as shown in fig. 14, only SDT DRB may be recovered, and non-SDT DRB may not be recovered. At this time, the BSR triggered and reported by the UE may be used to indicate not only the small packet data carried by the recovered SDT DRB, but also the large packet data carried by the non-recovered SDT DRB. Therefore, when the newly obtained second data packet is big packet data, the UE may trigger reporting of a BSR indicating big packet data carried by the non-SDT DRB.

In some embodiments, when the UE initiates 4step-SDT as shown in fig. 14, only SDT DRB may be recovered, and non-SDT DRB may not be recovered. When the UE initiates the 4step-SDT shown in fig. 14, if the second data packet is obtained, at this time, the NAS layer may instruct the RRC layer to send an RRC request message, where the RRC request message may correspond to the second data packet, that is, the RRC request message is sent when the UE requests to transmit the second data packet. That is, the UE may trigger reporting of a BSR indicating an RRC request message carried over the SRB.

The UE-initiated RA may be, but is not limited to, any one of the following requests:

the first condition is as follows: the UE may initiate an RA to the network device after waiting for the end of the currently ongoing SDT. That is, when the UE receives the RRC response message sent by the network device, the UE may determine that the current SDT is finished, and the description of the RRC response message may refer to the description of the RRC response message in fig. 5. For example, after S906, the UE receives the rrcreelease message sent by the network device, and then the UE may determine that the currently performed SDT is ended, and may directly initiate an RA. Thereby avoiding affecting the transmission delay of the currently transmitted first data packet.

Case two: the UE may end the currently ongoing SDT and initiate an RA directly to the network device. For example, the UE no longer listens to DCI sent by the network device, and the DCI is used for the network device to schedule a RAR or RRC response message in response to the random access preamble. Alternatively, the UE is performing 4 step-based RA. After the UE sends the random access preamble to the network device, the msg3 and the first packet are no longer sent to the network device. After the currently performed SDT is finished, the UE may directly initiate an RA, so as to enter an RRC CONNECTED state to transmit the first packet and the second packet. Thereby avoiding affecting the transmission delay of the new large packet data (i.e., the second data packet).

Case three: the UE may not stop the currently ongoing SDT, i.e., initiate an RA to the network device while the SDT is ongoing. For example, the UE is performing SDT based on 4step RA. After the UE sends the msg3 and the first data packet to the network device, the UE obtains a new second data packet before receiving an RRC response message sent by the network device. At this time, the UE may directly send the random access preamble to the network device, i.e., initiate 4step-RA, or send the random access preamble and msgA to the network device, i.e., initiate 2 step-RA. Thereby avoiding affecting the transmission delay of the new large packet data (i.e., the second data packet).

The order of S907 and S902, S903, S904, S905, and S906 is not limited, that is, S907 may be after S901 and before S908.

Referring to fig. 15, fig. 15 is a schematic flowchart of another data transmission method according to an embodiment of the present application. The method may be applied to the communication system shown in fig. 1, and the network device and the UE in the method may be the network device 120 and the UE130 shown in fig. 1. Fig. 15 illustrates an example in which the second packet is a large packet data. The method includes, but is not limited to, the steps of:

s1001: the UE obtains a first data packet.

Specifically, when the first data packet obtained by the UE is the packet data, the UE initiates 2step-SDT, that is, executes S1002.

S1002: the UE sends random access preamble, RRC request message and first data packet to the network equipment.

S1003: the network device restores the UE context and sends a first data packet to the core network.

S1004: the network device sends a content resolution message to the UE.

Specifically, S1002-S1004 is identical to S702-S704 of FIG. 12, and will not be described again. The order of S1003 and S1004 is not limited.

S1005: the UE obtains the second data packet.

S1006: and when the second data packet is big packet data, the UE initiates RA.

Specifically, S1006 is similar to S908 of fig. 14, and refer to the description of S908 of fig. 14 specifically, at this time, the UE without BSR resource example may refer to the description of S706 of fig. 12 above.

The order of S1005, S1002, S1003, and S1004 is not limited, and S1005 may be after S1001 and before S1006.

Not limited to the above-mentioned cases, in a specific implementation, if the UE and the network device obtain a new second packet when performing SDT and there is no resource for transmitting the second packet, the UE may also directly trigger reporting of an inactive SR, such as the first SR and the second SR. When the condition of reporting the inactive SR is satisfied, the UE may send the inactive SR to the network device. The condition for reporting the inactive SR may refer to the inactive SR and the description of the UE sending the first SR or the second SR to the network device in fig. 10 to 13.

In a possible implementation manner, when the UE and the network device perform 4step-SDT, the UE obtains new packet data (i.e. a second packet) before the first packet and the RRC request message are packaged, and the UE may carry the first indication information when sending msg3 to request the network device to schedule resources. In some embodiments, the UE obtains the second data packet, and the UE may first trigger reporting of the BSR, and if there is no resource for transmitting the BSR, the UE may carry the first indication information when sending the msg 3. The description of the resource for which the UE does not transmit BSR can be referred to the above description of the resource for which the UE does not transmit BSR in S508 of fig. 10 and S706 of fig. 12. A specific example of the process can be seen in fig. 16 below.

The first indication information may indicate that the UE has data to be transmitted, and optionally, the first indication information may indicate that the UE has packet data to be transmitted. In the SDT process, msg3 sent by the UE is actually MAC PDU obtained by the MAC layer. One MAC PDU may include a plurality of MAC sub-PDUs (sub-PDUs). Each MAC sub pdu may correspond to a MAC sub header (sub header), and the content included in each MAC sub pdu may be represented by the corresponding MAC sub header. For example, each MAC subheader may correspond to one MAC SDU (Service Data Unit) or one MAC CE. The network device may obtain the contents and the indicated function included in the MAC sub PDU through the MAC sub header in the MAC PDU. The MAC subheader may include fields such as: a Logical Channel Identity (LCID), a reserved bit (R), a field L and a field F for indicating the length of the MAC SDU or the MAC CE, and the like. The first indication information may be represented by a MAC subheader in the MAC PDU, and specific examples are as follows:

for example, the first indication information may be represented by a MAC subheader corresponding to a MAC SDU indicating the RRC request message.

Optionally, the first indication information may be represented by an LCID included in the MAC subheader, and a value of the LCID is a new value. The RRC request message is transmitted on the CCCH, that is, the LCID included in the MAC subheader corresponding to the RRC request message is the LCID of the CCCH. For example, the LCID included in the MAC subheader generally takes a value of 0, and 0 is the LCID of the logic channel CCCH. If the LCID value is 0, the network device may default that the UE does not have data to be transmitted. If the value of the LCID is not 0, for example, 35, the network device may determine that the UE has data to be transmitted.

Alternatively, the first indication information may be represented by a reserved bit in the MAC subheader. For example, when the reserved bit is 0, the network device may determine that the UE does not have data to be transmitted, and when the reserved bit is 1, the network device may determine that the UE has data to be transmitted.

In example two, the first indication information may be represented by a MAC subheader indicating a MAC SDU of a logical channel corresponding to the DRB.

Optionally, the first indication information may be represented by an LCID included in the MAC subheader, and a value of the LCID is a new value. For example, the LCID included in the MAC subheader generally has a value of 1 to 32, and the LCID has a positive integer. If the LCID value is any one of values 1 to 32, the network device may default that the UE does not have data to be transmitted. If the value of the LCID is not any one of values 1 to 32, for example, 38, the network device may determine that the UE has data to be transmitted.

In a specific implementation, the first indication information may also be represented by a MAC subheader of a MAC SDU of a logical channel corresponding to another DRB, and the application does not limit the specific representation of the first indication information.

Referring to fig. 16, fig. 16 is a schematic flowchart of another data transmission method according to an embodiment of the present application. The method may be applied to the communication system shown in fig. 1, and the network device and the UE in the method may be the network device 120 and the UE130 shown in fig. 1. Fig. 16 illustrates an example in which the second packet is a packet data. The method includes, but is not limited to, the steps of:

s1101: the UE obtains a first data packet.

Specifically, when the first data packet obtained by the UE is the packet data, the UE initiates 4step-SDT, that is, executes S1102.

S1102: and the UE sends random access preamble to the network equipment.

S1103: in response to the random access preamble, the network device sends a RAR to the UE.

Specifically, S1102-S1103 are identical to S201-S202 of fig. 6, and are not described again.

S1104: the UE obtains the second data packet.

S1105: and based on the resource scheduled by the RAR, the UE sends a third data packet, an RRC request message and first indication information to the network equipment.

Specifically, the UE may package the third data packet and the RRC request message to obtain the MAC PDU, where the third data packet may be a data packet with a higher priority in the first data packet and the second data packet. The UE obtains new packet data (i.e., the second data packet) before the group package. The UE may determine the content included in the MAC PDU according to the RAR scheduled resources.

And if the resource scheduled by the RAR is larger than the sum of the resources for transmitting the third data packet and the RRC request message but smaller than the sum of the resources for transmitting the third data packet, the RRC request message and the first BSR. The first BSR may indicate a data amount of a fourth packet, and the fourth packet may be a packet with a lower priority from among the first packet and the second packet. At this time, the UE may determine that the third packet is included in the transmitted MAC PDU without including the first BSR, thereby preventing the fourth packet of low priority from affecting the transmission of the third packet of high priority. In the above situation, the UE does not transmit the resource of the first BSR, and the UE may carry the first indication information in the MAC PDU during the packet packing, so as to notify the network device that a new packet arrives. The first indication information may be for the UE to request scheduling resources from the network device.

Illustratively, the third data packet is a first data packet and the fourth data packet is a second data packet. In S1105, the UE may send the first packet with a higher priority instead of sending the BSR indicating the data amount of the second packet, so as to avoid affecting transmission of the high-priority packet of the current SDT by the newly obtained low-priority packet.

S1106: the network equipment sends a content resolution message to the UE to indicate that the current SDT of the UE is successful.

S1107: in response to the first indication information, the network equipment allocates a second transmission resource for the UE.

Specifically, the network device may determine that the UE has packet data to be transmitted according to the first indication information in the MAC PDU, and dynamically schedule the second transmission resource for the UE. The second transmission resource is used for the UE to send a fourth data packet to the network device, i.e. for the UE to perform S1108.

The size of the second transmission resource dynamically scheduled by the network device for the UE may depend on the network device, for example, the network device may determine the size of the second transmission resource based on the current load status. Or, the resource size dynamically scheduled by the network device for the UE may satisfy the resource size of the scheduling packet data specified in the SDT process. Optionally, the second transmission resource is larger than a resource scheduled for the packet data specified in the currently performed SDT procedure.

S1108: the UE transmits a fourth data packet to the network device using the second transmission resource.

S1109: the network equipment sends a first response message to the UE.

Specifically, S1109 is the same as S205 of fig. 6, and the first response message is the RRC response message in fig. 5, for example, an rrcreelease message, which may specifically refer to the description of fig. 5 and is not repeated.

In some embodiments, when the UE and the network device perform 4step-SDT, if a new second data packet is obtained and the second data packet is packet data, the UE may trigger reporting of the BSR. If the second data packet is obtained by the UE before the first data packet and the RRC request message are packaged, and the UE does not report resources of the BSR, the UE may execute the process shown in fig. 16. If the second data packet is obtained by the UE after the first data packet and the RRC request message are packaged, and the UE does not report resources of the BSR, the UE may execute the procedure shown in fig. 10.

Without being limited to the above-listed cases, in a specific implementation, if the UE obtains the packet data, the UE may initiate 4-step-SDT or 2-step-SDT. Moreover, the UE may send the first indication information shown in fig. 16 together when sending msg3 or msgA, so that resources may report BSR or transmit new data when new data arrives subsequently, instead of initiating RA or SDT again, thereby avoiding unnecessary signaling overhead and power consumption and reducing data transmission delay.

In the method shown in fig. 16, if the UE obtains new packet data during the SDT process, the UE may trigger reporting of the BSR. If no BSR resource is reported, the UE can send a third data packet with higher priority in the current SDT process, and timely notify the network equipment of new packet data arrival through the first indication information carried in the msg3, so that the influence of the low-priority data packet on the transmission of the high-priority data packet is avoided, and the transmission delay of the low-priority data packet is reduced. In addition, the UE can continuously transmit the packet data with low priority in a non-connection state without initiating a new RA or SDT, thereby avoiding unnecessary signaling overhead and power consumption.

In a specific implementation, if the second packet newly obtained when the UE and the network device perform SDT is big packet data, the UE may also notify the network device of the arrival of the new packet in time through the first indication information carried in msg3 to request the network device to schedule resources. Optionally, the UE obtains the second data packet, the UE may trigger reporting of the BSR first, and if there is no resource for transmitting the BSR, the UE may carry the first indication information when sending the msg 3. The description that the UE does not transmit the BSR resource may be referred to as the description that the UE does not transmit the BSR resource in S608 in fig. 11 and S706 in fig. 12. This is not a limitation of the present application.

Not limited to the above-mentioned cases, in a specific implementation, the resource scheduled by the RAR may also be greater than the sum of the resources for transmitting the first data packet, the second data packet, and the RRC request message, and the UE may send the first data packet, the second data packet, and the RRC request message to the network device based on the resource scheduled by the RAR.

Or, the resource scheduled by the RAR may also be greater than the sum of the resources for transmitting the third data packet, the RRC request message, and the first BSR, that is, the UE has BSR resources for reporting the first BSR, so the UE may send the third data packet, the RRC request message, and the first BSR to the network device based on the resource scheduled by the RAR. The first BSR may indicate an amount of data of the fourth packet. The network device may synthesize the scheduling resources according to the first BSR, for example, may dynamically schedule the second transmission resource for the UE, so that the UE transmits the fourth data packet to the network device based on the second transmission resource.

In a possible implementation manner, when the UE and the network device perform SDT, a new data packet is obtained, and the UE may trigger reporting of the BSR. If the UE has resources to report the BSR, the UE may send the BSR to the network device. And the network equipment determines that the data to be transmitted by the UE is big packet data or small packet data according to the reported BSR, so that the network equipment can conveniently and comprehensively schedule resources for the UE. The flow example is shown in fig. 17 and fig. 18 below, and fig. 17 and fig. 18 illustrate an example where the ongoing SDT of the UE is 4 step-SDT.

The BSR sent by the UE is actually BSR MAC CE obtained by the MAC layer. The BSR MAC CE may be a short BSR MAC CE (short BSR MAC CE) or a short truncated BSR MAC CE (short truncated BSR MAC CE), and the included fields may be referred to in table 1 below; it may also be a long BSR MAC CE (long BSR MAC CE), or a long truncated BSR MAC CE (long truncated BSR MAC CE), and the included fields may be as shown in table 2 below.

TABLE 1 fields included in a short BSR MAC CE or a short truncated BSR MAC CE

LCG ID

buffer size (size)

The field LCG ID may include an identifier of an LCG reported by the UE, that is, an identifier of an LCG having data to be transmitted. The length of the field LCG ID is 3 bits. The field buffer size is used for indicating the data volume to be transmitted in the LCG reported by the UE.

TABLE 2 fields included in Long BSR MAC CE or Long truncated BSR MAC CE

Wherein, the field LCGi is used for indicating whether the logical channel group i has data to be transmitted. The positive integer i can identify a logical channel group, and the value range of i is greater than or equal to 0 and less than or equal to 7. The value of the field LCGi is that the first value indicates that the logical channel group i has data to be transmitted, and the value is that the second value identifies that the logical channel i does not have data to be transmitted. For example, LCG1 is used to indicate whether logical channel group 1 has data to transmit. When the field LCGi is 1, it indicates that there is data to be transmitted in the logical channel group i, and indicates that the BSR includes the amount of data to be transmitted in the logical channel group i. When the field LCGi is 0, it indicates that there is no data to be transmitted in the logical channel group i.

The field buffer size j is used for indicating the data amount to be transmitted in the jth LCG with the data to be transmitted. For example, if j is 3, LCG0, LCG1, and LCG3 are all 1, and LCG2, LCG4, LCG5, LCG6, and LCG7 are all 0. Thus, buffer size1 is used to indicate the amount of data to be transmitted in logical channel group 0, buffer size2 is used to indicate the amount of data to be transmitted in logical channel group 1, and buffer size3 is used to indicate the amount of data to be transmitted in logical channel group 3.

As can be seen from the above description, the BSR MAC CE reported by the UE is reported in an LCG manner, that is, the BSR MAC CE is used to indicate the amount of data to be transmitted in at least one LCG, and may be referred to as the BSR MAC CE to indicate the at least one LCG for short. The network device may obtain the data amount to be transmitted in the at least one LCG through the BSR MAC CE, but may not obtain the data amount to be transmitted in each logical channel included in each LCG.

In this application, when the network device configures the logical channel for the UE, the logical channel included in the SDT DRB and the logical channel included in the non-SDT DRB may be placed in different LCGs. That is, the LCG of the logical channel included in the at least one SDT DRB may be configured as a first LCG, and the LCG of the logical channel included in the at least one non-SDT DRB may be configured as a second LCG. At this time, the first LCG can be said to be the LCG corresponding to the SDT DRB, and the second LCG is said to be the LCG corresponding to the non-SDT DRB. It is understood that the logical channels in the first LCG are used for transmitting small packets of data and the logical channels in the second LCG are used for transmitting large packets of data. The first LCG and the second LCG are each at least one LCG.

Illustratively, the network device may configure the first LCG and the second LCG for the UE through an RRC response message (e.g., an rrcreelease message). Or the network device may configure the first LCG and the second LCG for the UE when the UE is in the RRC CONNECTED state.

After receiving the BSR MAC CE sent by the UE, the network device may determine the first LCG or the second LCG of the indicated LCG, that is, determine that the data to be transmitted in the indicated LCG is small packet data or large packet data. When the LCG indicated by the BSR MAC CE is the first LCG, the network device may determine that the data to be transmitted by the UE is the packet data. When the LCG indicated by the BSR MAC CE is the second LCG, the network device may determine that the data to be transmitted by the UE is large packet data.

Illustratively, in fig. 9 above, DRBs 1 and DRBs 2 are SDT DRBs for transporting small packet data, and DRBs 3 and DRBs 4 are non-SDT DRBs for transporting large packet data. Logical channel 1 included in DRB1 and logical channel 2 included in DRB2 may both belong to the first LCG, assuming that the first LCG is logical channel group 2. Logical channel 3 included in DRB3 and logical channel 4 included in DRB3 may both belong to the second LCG, assuming that the second LCG is logical channel group 3. If the BSR MAC CE sent by the UE indicates the logical channel group 2 and does not indicate the logical channel group 3, for example, the BSR MAC CE is a short BSR MAC CE, and the LCG ID of the BSR MAC CE includes the identifier of the logical channel group 2. Or, the BSR MAC CE is long BSR MAC CE, LCG2 of the BSR MAC CE is 1, and LCG3 is 0. Then, the network device may determine, according to the BSR MAC CE sent by the UE, that the logical channel group 2 has packet data to be transmitted, and the amount of data to be transmitted in the logical channel group 2.

Referring to fig. 17, fig. 17 is a schematic flowchart of another data transmission method according to an embodiment of the present application. The method may be applied to the communication system shown in fig. 1, and the network device and the UE in the method may be the network device 120 and the UE130 shown in fig. 1. The method includes, but is not limited to, the steps of:

s1201: the UE obtains a first data packet.

Specifically, when the first data packet obtained by the UE is the packet data, the UE initiates 4step-SDT, that is, executes S1202.

S1202: and the UE sends random access preamble to the network equipment.

S1203: in response to the random access preamble, the network device sends a RAR to the UE.

Specifically, S1202-S1203 are identical to S201-S202 of fig. 6, and are not described again.

S1204: the UE obtains the second data packet.

S1205: based on the resources scheduled by the RAR, the UE sends a first data packet, an RRC request message and a third BSR to the network equipment.

Specifically, when the UE obtains the second data packet, the UE may trigger reporting of the BSR. For example, the BSR may be triggered by a second packet, or the BSR may be a BSR that has been triggered during a current UE-initiated SDT procedure. When the resource scheduled by the RAR is less than the sum of the resources for transmitting the first data packet, the RRC request message, and the second data packet, but greater than or equal to the sum of the resources for transmitting the first data packet, the RRC request message, and the third BSR, that is, the UE has a resource for reporting the third BSR, the UE may perform S1205. The third BSR may indicate an amount of data of the second packet. If the second data packet is small packet data, the LCG indicated in the third BSR is a first LCG corresponding to the SDT DRB, and if the second data packet is large packet data, the LCG indicated in the third BSR is a second LCG corresponding to the non-SDT DRB.

S1206: the network equipment sends a content resolution message to the UE to indicate that the current random access of the UE is successful.

S1207: in response to the third BSR, the network device allocates the first transmission resource to the UE or sends a second response message to the UE.

Specifically, if the LCG indicated by the third BSR is the first LCG corresponding to the SDT DRB, the network device may determine that the UE has the packet data to be transmitted. The network device may dynamically schedule a first transmission resource for the UE, where the first transmission resource is used for the UE to transmit the second data packet, which may be described in S510-S511 of fig. 10. If the LCG indicated by the third BSR is the second LCG corresponding to the non-SDT DRB, the network device may determine that the UE has the large packet data to be transmitted. The network device may send a second response message to the UE to instruct the UE to enter an RRC CONNECTED state. The UE may enter the RRC CONNECTED state and then transmit the second packet.

It should be noted that the UE may obtain the second data packet before the RRC request message and the first data packet are packaged, that is, the sequence of S1204, S1202 and S1203 is not limited.

Referring to fig. 18, fig. 18 is a schematic flowchart of another data transmission method according to an embodiment of the present application. The method may be applied to the communication system shown in fig. 1, and the network device and the UE in the method may be the network device 120 and the UE130 shown in fig. 1. The method includes, but is not limited to, the steps of:

s1301: the UE obtains a first data packet.

Specifically, when the first data packet obtained by the UE is the packet data, the UE initiates 4step-SDT, that is, executes S1302.

S1302: and the UE sends random access preamble to the network equipment.

S1303: in response to the random access preamble, the network device sends a RAR to the UE.

Specifically, S1302-S1303 are identical to S201-S202 of fig. 6, and are not described again.

S1304: based on the resources scheduled by the RAR, the UE sends an RRC request message, a first data packet and a fourth BSR to the network equipment.

Specifically, when the UE initiates the 4step-SDT shown in fig. 18, reporting of the fourth BSR may be triggered. For example, when the UE obtains the first packet, the NAS layer instructs the RRC layer to send an RRC request message, which may be applied to the 4step-SDT shown in fig. 18, that is, corresponding to the first packet. At this time, the UE may trigger reporting of a fourth BSR indicating an RRC request message carried over the SRB.

Exemplarily, when the resource scheduled by the RAR is smaller than the sum of the resources for transmitting the first packet and the RRC request message, the UE cannot complete transmission of the first packet through one msg3 transmission, and thus, the UE may transmit the first part of data in the first packet and the fourth BSR in S1304. The first data packet is the second part of data except the first part of data. The fourth BSR may indicate a data amount of the second portion of data.

S1305: the network device restores the UE context and sends a first data packet to the core network.

S1306: the network device sends a content resolution message to the UE.

Specifically, S1305-S1306 is identical to S505-S506 of FIG. 10, and will not be described in detail. The order of S1305 and S1306 is not limited.

S1307: in response to the fourth BSR, the network device allocates a third transmission resource for the UE.

Specifically, the third transmission resource is used for the UE to perform a subsequent transmission. For example, the network device dynamically schedules a third transmission resource for the UE, so that the UE transmits the second part of data in the first data packet by using the third transmission resource.

S1308: the UE obtains the second data packet.

S1309: the UE transmits a third BSR to the network device using the third transmission resource.

Specifically, when the UE obtains the second data packet, the second data packet may trigger reporting of the third BSR. The network device has already dynamically scheduled the third transmission resource for the UE, and since the priority of reporting the BSR is higher than the priority of reporting the service data, the UE can preferentially send the third BSR using the third transmission resource after obtaining the third transmission resource. That is, when the UE has resources to report the third BSR, the UE may send the third BSR to the network device using the third transmission resources. If the second data packet is small packet data, the LCG indicated in the third BSR is a first LCG corresponding to the SDT DRB, and if the second data packet is large packet data, the LCG indicated in the third BSR is a second LCG corresponding to the non-SDT DRB.

S1310: in response to the third BSR, the network device allocates a first transmission resource to the UE or sends a second response message to the UE.

Specifically, S1310 is identical to S1207 of fig. 17, and will not be described again.

It should be noted that the UE may obtain the second data packet after the RRC request message is packaged with the first data packet, that is, the sequence of S1308 and S1305, S1306, and S1307 is not limited.

It is understood that the procedure of 2step-SDT is similar to the procedure of fig. 18 above, except that in 2step-SDT, the fourth BSR is transmitted together with msgA, and will not be described again.

In some embodiments, in the case that the UE and the network device obtain a new second data packet during SDT, if the UE has no BSR resource, the UE may perform the procedures shown in fig. 10 to fig. 16. If the UE has BSR resources, the UE may perform the procedures shown in fig. 17-18.

In a specific implementation, when the UE in the RRC CONNECTED state obtains a data packet, reporting the BSR may also be triggered. When the UE has resources to report the BSR, the UE may send, to the network device, the BSR indicating that there is big packet data to be transmitted or LCG with small packet data to be transmitted, which may be specifically referred to the description of the BSR. The network device may comprehensively schedule transmission resources according to the reported BSR, which may specifically refer to the description of S1207 in fig. 17.

In the methods shown in fig. 17 and fig. 18, when the UE and the network device perform SDT, the UE obtains the second data packet, and the UE may trigger reporting of the BSR. The UE can inform the network equipment of the arrival of a new data packet in time through the BSR, and inform the network equipment of the new data packet as big data packet or small data packet through the BSR with different contents. When the new data packet is packet data, the network device may dynamically schedule the first transmission resource for the UE, so that the UE sends the new data packet using the first transmission resource, that is, the UE may continue to transmit the packet data in the non-connected state. And when the new data packet is big packet data, the network equipment indicates the UE to enter an RRC connected state so that the UE sends the big packet data in the RRC connected state. The UE does not need to initiate a new RA or SDT, so that transmission resources are saved, and unnecessary signaling overhead and power consumption are avoided. Meanwhile, the transmission delay of the second data packet is reduced under the condition that the transmission delay of the first data packet is not influenced.

In one possible implementation, the network equipment to which the UE is connected may change as the UE is mobile. Assume that the network device to which the UE is originally connected is the first device, and the first device configures an inactive SR (i.e., the first SR, and optionally the second SR) for the UE. The network device to which the UE is connected changes, i.e. switches from the first device to the second device. The second device may exchange messages with the first device through the Xn interface, thereby acquiring the UE context information and capability information of the UE. The capability information of the UE may include whether the UE supports inactive SR. In a specific implementation, the second device may interact with the first device through the Xn interface to obtain inactive SR configuration information, inactive SR resource configuration information, and the like of the UE. Specific flow examples are shown in fig. 19 to 20 below.

Referring to fig. 19, fig. 19 illustrates a flowchart for acquiring capability information of a UE. The method may be applied to the communication system shown in fig. 1, and the first device and the second device in the method may be the network device 120 shown in fig. 1, and the UE may be the UE130 shown in fig. 1. The method includes, but is not limited to, the steps of:

s1401: the UE obtains a first data packet.

S1402: the UE sends an RRC request message and a first data packet to the second device.

Specifically, when the first data packet obtained by the UE is packet data, the UE initiates SDT. For example, if the SDT is 4step-SDT, S1402 is a step of transmitting msg 3. Or the SDT is 2step-SDT, S1402 is a step of transmitting msgA.

Prior to S1401, the method further comprises: the UE is connected with the first equipment, and the UE cancels the connection with the first equipment and is connected with the second equipment. That is, the network device to which the UE is connected may be handed off from the first device to the second device.

S1403: the second device transmits a retrieve UE context request (retrieve UE context request) message to the first device.

Specifically, the retrieve UE context request message may be used to request to acquire UE context information and capability information of the UE. The capability information of the UE may include whether the UE supports inactive SR.

Illustratively, a first Information Element (IE) is newly added to the retrieve UE context request message, and the first IE is used to request to acquire capability information of the UE. And when the values of the first IE are different, the first IE is used for indicating whether the capability information of the UE is requested to be acquired or not. For example, the first IE has a value of 0 or 1, or a value of true or false. The value of 1 or true indicates that the capability information of the UE is requested to be acquired, and the value of 0 or false indicates that the capability information of the UE is not requested to be acquired. Without being limited thereto, whether to request to acquire the capability information of the UE may also be indicated by whether to carry the first IE. When the retrieve UE context request message carries the first IE, the request for acquiring the capability information of the UE is shown, and when the first IE is not carried, the request for acquiring the capability information of the UE is shown.

S1404: the first device transmits a retrieve UE context response (retrieve UE context response) message to the second device.

Specifically, the retrieve UE context response message may include UE context information and capability information of the UE. The retrieve UE context response message may be a message that is sent to the second device when the first device acquires the UE context information of the UE.

Illustratively, a second IE is newly added to the retrieve UE context request message. And when the values of the second IE are different, the second IE is used for indicating whether the UE supports inactive SR. For example, the second IE takes a value of 0 or 1, or takes a value of true or false. The value of 1 or true indicates that the UE supports inactive SR, and the value of 0 or false indicates that the UE does not support inactive SR. Without being limited thereto, whether the UE supports inactive SR may also be indicated by whether the second IE is carried. When the retrieve UE context request message carries the second IE, the UE supports the inactive SR, and when the second IE is not carried, the UE does not support the inactive SR.

S1405: after obtaining the UE context of the UE, the second device performs a path switch (path switch) process with the core network.

S1406: the second device sends the first data packet to the core network.

Specifically, the second device acquires the UE context information and the capability information of the UE according to the retrieve UE context request message. After the second device obtains the context information of the UE, the second device may perform a path switch with the core network, and the subsequent second device may forward the data packet sent by the UE to the core network.

S1407: the second device sends a first response message to the UE.

Specifically, the first response message is an RRC response message, such as an rrcreelease message, which can be specifically referred to the description of the RRC response message in fig. 5 above. In some embodiments, if the first device acquires that the UE supports inactive SR, the second device may configure the inactive SR for the UE through the first response message (e.g., the first SR and the second SR).

S1408: the second device sends a UE context release (UE context release) message to the first device.

Specifically, the second device requests the first device to release the UE context of the UE through a UE context release message. After the first device releases the UE context, the first device cannot forward the data sent by the UE to the core network.

Referring to fig. 20, fig. 20 is a schematic diagram illustrating another flow for acquiring capability information of a UE. The method may be applied to the communication system shown in fig. 1, and the first device and the second device in the method may be the network device 120 shown in fig. 1, and the UE may be the UE130 shown in fig. 1. The method includes, but is not limited to, the steps of:

s1501: the UE obtains a first data packet.

S1502: the UE sends an RRC request message and a first data packet to the second device.

S1503: the second device transmits a retrieve UE context request message to the first device.

Specifically, S1501 to S1503 coincide with S1401 to S1403 of fig. 19 above, and are not described in detail.

S1504: the first device sends a retrieve UE context failure message to the second device.

Specifically, the retrieve UE context failure message may include capability information of the UE. The retrieve UE context failure message may be a message sent to the second device when the first device cannot acquire the UE context information of the UE, and optionally, the retrieve UE context failure message may include a reason why the acquisition of the UE context information fails. The example of whether the retrieve UE context failure message indicates that the UE supports the inactive SR is similar to the example of whether the retrieve UE context request message indicates that the UE supports the inactive SR in S1404 of fig. 19, and is not described again.

S1505: the second device sends the first data packet to the first device.

S1506: the first device sends a first data packet to a core network.

Specifically, the second device may acquire capability information (e.g., inactive SR information) of the UE according to a retrieve UE context failure message. If the second device cannot recover the UE context of the UE, the second device cannot forward the first data packet sent by the UE to the core network. In this case, the second device may send the first data packet to the first device to cause the first device to forward the first data packet to the core network.

S1507: the second device sends a first response message to the UE.

Specifically, the first response message is an RRC response message, such as an rrcreelease message, which can be specifically referred to the description of the RRC response message in fig. 5 above.

In a possible implementation manner, the UE may release an inactive SR configured for the UE by the network device, and specifically may release configuration information of the inactive SR and/or resource configuration information of the inactive SR. The description of the configuration information and the resource configuration information can be referred to the description of the SR configuration information and the SR resource configuration information in fig. 4 above. The case where the UE releases inactive SR includes, for example and without limitation: the UE performs cell reselection, and receives an RRC response message (for example, an rrcreelease message) sent by the network device, where the uplink synchronization is not maintained (that is, the TAT is not kept running), and so on. After receiving the RRC response message, the UE may enter an RRC CONNECTED state, but not limited to, determine that the SDT procedure is ended, and the like. The RRC response message is specifically described above with reference to the RRC response message in fig. 5.

For example, when the UE does not perform cell reselection or handover a connected network device, if the UE satisfies the above-mentioned condition of releasing the UE inactive SR, only the resource configuration information of the inactive SR may be released, but not the configuration information of the inactive SR. Alternatively, the UE may release the configuration information of the inactive SR and the resource configuration information of the inactive SR.

Illustratively, when the UE performs cell reselection or switches a connected network device, the UE may release the configuration information of the inactive SR and the resource configuration information of the inactive SR.

In one possible implementation, the inactive SR configured by the network device for the UE may include multiple sets of resources for transmitting the inactive SR, which are referred to as inactive SR resources for short. And, each inactive SR resource set may correspond to at least one beam (beam). Or the inactive SR configured by the network device for the UE may include configuration of multiple sets of inactive SRs, which is abbreviated as inactive SR configuration. And, each inactive SR configuration set may correspond to at least one beam. When the UE sends an inactive SR to the network device, the network device may determine, according to an inactive SR resource or an inactive SR configuration (e.g., SR configuration ID) corresponding to the inactive SR, that at least one beam corresponding to the inactive SR is a beam with better quality for the UE to currently receive downlink data, thereby implementing beam update of the UE in the non-connected state. The subsequent network device may transmit downlink data to the UE based on the at least one beam. The UE does not need to report Reference Signal Receiving Power (RSRP) of the beam to the network device, and the network device can acquire the beam with better quality of the downlink data currently received by the UE, thereby reducing unnecessary signaling overhead and power consumption.

It can be understood that, in conjunction with the SDTs shown in fig. 5-8, the case where the first data packet transmitted in the ongoing SDT is the downlink packet data is similar to the case where the first data packet is the uplink data packet.

Illustratively, assume that the UE and the network device are performing 4step-SDT, and the first data packet of the SDT transmission is downlink packet data. If the UE obtains a new second packet before sending msg3, e.g., after S201 and before S203 as shown in fig. 6 above. When the second packet is small packet data, the UE may send the second packet directly in msg 3. The UE may trigger reporting of the BSR. When the second data packet is large packet data, if there is BSR resource, the UE may report BSR, and the specific procedure may refer to fig. 17 to fig. 18. If there is no BSR resource, the UE may trigger reporting of the inactive SR, and if there is a resource sending the inactive SR, the UE may send a second SR to the network device, and the specific process may be as shown in fig. 11. If there is no resource to send the inactive SR, the UE may initiate a new RA, and the specific procedure may refer to fig. 14 above.

If the UE obtains a new second packet after sending msg3, e.g., after S203 and before S205 as shown in fig. 6 above. The UE may trigger reporting of the BSR. When the second data packet is packet data, if BSR resources exist, the UE may report BSR, and the specific process may refer to fig. 17 to fig. 18. If there is no BSR resource, the UE may trigger reporting of an inactive SR, and if there is a resource sending the inactive SR, the UE may send a first SR to the network device, and the specific process may be as shown in fig. 10. When the second data packet is large packet data, if there is BSR resource, the UE may report BSR, and the specific procedure may refer to fig. 17 to fig. 18. If there is no BSR resource, the UE may trigger reporting of the inactive SR, and if there is a resource sending the inactive SR, the UE may send a second SR to the network device, and the specific process may be as shown in fig. 11. If there is no resource to send the inactive SR, the UE may initiate a new RA, and the specific procedure may refer to fig. 14 above.

Illustratively, assume that the UE and the network device are performing 2step-SDT, and the first data packet of the SDT transmission is downlink packet data. If the UE obtains a new second data packet, for example, after S401 and before S403 shown in fig. 8. The UE may trigger reporting of the BSR. If there is BSR resource, the UE may report BSR, and the specific procedure may refer to fig. 17 to fig. 18. If there is no BSR resource, the UE may trigger reporting of inactive SR. When the second data packet is packet data, if there is a resource for sending an inactive SR, the UE may send the first SR to the network device, and the specific process may refer to fig. 12 above. When the second data packet is big packet data, if there is a resource for sending an inactive SR, the UE may send the second SR to the network device, and the specific process may refer to fig. 13 above. If there is no resource to send the inactive SR, the UE may initiate a new RA, and the specific procedure may refer to fig. 15 above.

In this application, when the UE and the network device are performing SDT, an example of a scenario in which the UE obtains a new packet is as follows:

for example, the first UE and the second UE may be smartphones, and the first UE and the second UE may both install social applications. The network device may be connected to an application server of the social application, but is not limited thereto, and the network device may be the application server of the social application. The first UE in the non-connected state can receive a first operation of a user based on a social application, and the first operation is used for sending first text information input by the user to the second UE. The first text information is a first data packet, and the first data packet is packet data. The first UE may initiate an RA-based SDT to the network device to send the first data packet to the network device, where the network device sends the first data packet to an application server of the social application, and then the application server of the social application sends the first data packet to the second UE. When the first UE performs the SDT based on the RA, the first UE receives a second operation of the user based on the social application, and the second operation is used for sending second text information input by the user to the second UE. The second text message is a second data packet, and the second data packet is also packet data. At this time, reporting of the BSR may be triggered, but there is no BSR resource, and reporting of the inactive SR may be triggered, so that the first UE may send the first SR to the network device. The network device may dynamically schedule uplink resources for the first UE in response to the first SR. The UE may send the second data packet to the network device based on the uplink resource, and the network device sends the second data packet to the application server of the social application, and then the application server of the social application sends the second data packet to the second UE.

Or when the first UE performs the SDT based on the RA, the first UE receives a third operation of the user based on the social application, and the third operation is used for sending the video file to the second UE. The video file is the second data packet, and the second data packet is big packet data. The first UE may send a second SR to the network device, and the network device may instruct the first UE to enter an RRC CONNECTED state in response to the second SR. Alternatively, the first UE may initiate a new RA to the network device to enter the RRC CONNECTED state. And the first UE in the RRC CONNECTED state sends the second data packet to the network equipment, the network equipment sends the second data packet to an application server of the social application, and the application server of the social application sends the second data packet to the second UE.

In example two, the UE is a smart band, and the UE may be installed with an application (referred to as a health application for short) for recording exercise data or health data. The network device may be connected to an application server of the health application, but is not limited thereto, and the network device may be an application server of the health application. When the user uses the UE, the UE in the unconnected state may periodically send the positioning information to the network device, where the positioning information is the first data packet. The first data packet is packet data. The UE may initiate an RA-based SDT to the network device to send the first data packet to the network device. However, when the UE performs the above-mentioned RA-based SDT, the UE receives a third operation of the user based on the health application, where the third operation is used to upload exercise data or health data of the user to an application server of the health application. The exercise data or health data of the user is the second data packet, and the second data packet is the big packet data. At this time, reporting of the BSR may be triggered, but there is no BSR resource, and reporting of the inactive SR may be triggered, so that the first UE may send the second SR to the network device. The network device may instruct the first UE to enter an RRC CONNECTED state in response to the second SR. Alternatively, the first UE may initiate a new RA to the network device to enter the RRC CONNECTED state. And the first UE in the RRC CONNECTED state sends the second data packet to the network equipment, and the network equipment sends the second data packet to an application server of the health application.

Not limited to the above-mentioned application scenarios, in a specific implementation, if the UE is a smart phone, the packet data is, for example: instant messaging messages, push messages of the application program, heartbeat packets of the application program, and indication messages that the application program remains active. If the UE is not a smart phone, for example, the UE is a wearable device such as a smart band or a smart watch, the packet data is, for example, positioning information periodically sent. For example, the UE is a sensor such as a temperature sensor or a pressure sensor or is in an industrial wireless sensor network, and the packet data is, for example, a detection signal (e.g., a temperature value or a pressure value) that is periodically transmitted or triggered to be transmitted. For example, the UE is a smart meter such as a smart meter or is in a smart meter network, and the packet data is, for example, a reading sent periodically.

One of ordinary skill in the art will appreciate that all or part of the processes in the methods of the above embodiments can be implemented by hardware associated with a computer program that can be stored in a computer-readable storage medium, and when executed, can include the processes of the above method embodiments. And the aforementioned storage medium includes: various media that can store computer program code, such as read-only memory (ROM) or Random Access Memory (RAM), magnetic or optical disks, etc.

Claims

1. A data transmission method, applied to a terminal, wherein the terminal is in a non-connected state, the method comprising:

the terminal obtains a first data packet, wherein the first data packet is packet data;

the terminal and the network equipment perform a packet data transmission process; the transmission process of the small packet data comprises the steps that the terminal sends a random access preamble, the first data packet and a Radio Resource Control (RRC) request message to the network equipment, and the terminal receives an RRC response message sent by the network equipment;

in the packet data transmission process, the terminal obtains a second data packet;

if the second data packet is packet data, the terminal sends a first Scheduling Request (SR) to the network equipment, wherein the first SR is used for requesting scheduling resources;

the terminal receives a first transmission resource scheduled by the network equipment for the terminal in response to the first SR;

and the terminal sends the second data packet to the network equipment by using the first transmission resource.

2. The method of claim 1, wherein the first SR is used to request scheduling resources for the packet data, the method further comprising:

if the second data packet is big packet data, the terminal sends a second SR to the network device, the second SR is used for requesting scheduling resources of the big packet data, and the RRC response message in the small packet data transmission process is sent by the network device in response to the second SR;

the terminal enters an RRC connected state in response to the RRC response message;

and the terminal sends the second data packet to the network equipment.

3. The method of claim 1, wherein the method further comprises:

if the second data packet is big packet data, the terminal executes a random access process;

the terminal enters an RRC connection state based on the random access process;

and the terminal sends the second data packet to the network equipment.

4. The method of claim 3, wherein the terminal and the network device perform a random access procedure comprising: the terminal interrupts the packet data transmission process and executes the random access process;

after the terminal enters an RRC connected state based on the random access process, the method further comprises the following steps: and the terminal sends the first data packet to the network equipment.

5. The method of claim 2, wherein the method further comprises:

and under the condition that the terminal does not send BSR resources to the network equipment, the terminal triggers and reports the first SR or the second SR.

6. The method according to any of claims 1-3, wherein when the terminal and the network device perform the small packet data transmission procedure, the terminal recovers Data Radio Bearers (DRBs) for transmitting small packet data and DRBs for transmitting large packet data.

7. The method of claim 2, wherein the logical channel corresponding to the first SR is a logical channel included in a first DRB, the first DRB is a DRB for transmitting small packet data, the logical channel corresponding to the second SR is a logical channel included in a second DRB, and the second DRB is a DRB for transmitting large packet data.

8. The method of claim 2, wherein the terminal maintains uplink synchronization when the terminal sends the first SR to the network device, and/or wherein the terminal maintains uplink synchronization when the terminal sends the second SR to the network device.

9. The method of claim 2, wherein before the terminal and the network device perform the packet data transmission procedure, the method further comprises: the terminal receives a configuration message sent by the network equipment, wherein the configuration message comprises information of the first SR and the second SR; the terminal determines that the information of the first SR and the second SR is effective; or the like, or, alternatively,

before the terminal and the network device perform the packet data transmission process, the method further includes: the terminal receives a configuration message sent by the network equipment, wherein the configuration message comprises information of the first SR and the second SR; the terminal receives an effective message sent by the network equipment, wherein the effective message is used for indicating that the information of the first SR and the second SR takes effect;

wherein the information of the first and second SRs includes configuration information of the first and second SRs and resource information of the first and second SRs.

10. The method of claim 9, wherein the method further comprises:

when a preset condition is met, the terminal releases configuration information of the first SR and the second SR, and/or resource information of the first SR and the second SR; the preset condition comprises at least one of the following conditions: the terminal performs cell reselection, the terminal does not maintain uplink synchronization, the terminal receives an RRC response message sent by the network device, and the RRC response message is used to indicate any one of the following: and the terminal enters an RRC connection state, and the transmission process of the small packet data is finished.

11. The method of claim 2, wherein the capability information of the first SR and the second SR is acquired by the network device from a network device to which the terminal has previously connected.

12. The method of claim 1, wherein the method further comprises: the terminal determines a first beam, and the terminal determines the first SR according to the first beam; the first beam is a beam for the terminal to send the first SR to the network device, or a beam corresponding to the first SR; the network device is configured to determine a second beam according to the first SR after receiving the first SR, where the second beam is a beam for the network device to send downlink data to the terminal; or the like, or, alternatively,

the method further comprises the following steps: the terminal determines a first beam, and the terminal determines the second SR according to the first beam; the first beam is a beam for the terminal to send the second SR to the network device, or a beam corresponding to the second SR; the network device is configured to determine a second beam according to the second SR after receiving the second SR, where the second beam is a beam for the network device to send downlink data to the terminal.

13. A data transmission method, applied to a terminal, wherein the terminal is in a non-connected state, the method comprising:

the terminal obtains a first data packet; the first data packet is packet data;

the terminal and the network equipment perform a packet data transmission process; the small packet data transmission process comprises the steps that the terminal sends a random access preamble, the first data packet and an RRC request message to the network equipment, and the terminal receives an RRC response message sent by the network equipment;

under the condition that the second data packet is packet data, the terminal sends a first BSR to the network equipment to obtain a first transmission resource scheduled for the terminal by the network equipment in response to the first BSR;

14. The method of claim 13, wherein the first BSR includes a first field indicating transmission resources for acquiring small packet data, and wherein the first BSR includes a second field indicating transmission resources for acquiring large packet data.

15. The method of claim 14, wherein the first field indicates a first logical channel group including logical channels for transmitting small packet data, and wherein the second field indicates a second logical channel group including logical channels for transmitting large packet data.

16. A data transmission method, applied to a terminal, wherein the terminal is in a non-connected state, the method comprising:

the terminal acquires a first data packet, wherein the first data packet is packet data;

the terminal sends a random access preamble to the network equipment;

the terminal obtains a second data packet;

the terminal sends a third data packet, an RRC request message and first indication information to the network equipment, wherein the first indication information is used for requesting to schedule resources; the third data packet is a data packet with higher priority in the first data packet and the second data packet;

the terminal receives a first transmission resource scheduled for the terminal by the network equipment in response to the first indication information;

17. The method of claim 16, wherein the terminal sends the third packet with a higher priority than the terminal sends a BSR, and wherein the terminal sends the third packet, the RRC request message, and the first indication information to the network device, comprising:

and under the condition that the terminal does not send the resource of the BSR to the network equipment, the terminal sends the third data packet, the RRC request message and the first indication information to the network equipment.

18. A data transmission method, applied to a network device, the method comprising:

the network equipment and the terminal in the non-connection state carry out a packet data transmission process; the small packet data transmission process comprises the steps that the network equipment receives a random access preamble, a first data packet and an RRC request message sent by the terminal, and the network equipment sends an RRC response message to the terminal; the first data packet is packet data obtained by the terminal;

the network equipment receives a first SR sent by the terminal, wherein the first SR is sent by the terminal when a second data packet is packet data, and the second data packet is obtained by the terminal in the transmission process of the packet data;

the network equipment responds to the first SR to schedule first transmission resources for the terminal;

and the network equipment receives the second data packet sent by the terminal by using the first transmission resource.

19. The method of claim 18, wherein the method further comprises:

the network equipment receives a second SR sent by the terminal, wherein the second SR is sent by the terminal when the second data packet is big packet data; the RRC response message in the packet data transmission process is sent by the network equipment in response to the second SR, and the RRC response message is used for indicating the terminal to enter an RRC connected state;

and the network equipment receives the second data packet sent by the terminal in the RRC connection state.

20. The method of claim 18, wherein the method further comprises:

and the network equipment receives the second data packet sent by the terminal in an RRC connection state, wherein the RRC connection state is entered by the terminal in a random access process executed under the condition that the second data packet is big packet data.

21. The method according to any of claims 18-20, wherein when the terminal and the network device perform the small packet data transmission procedure, the terminal recovers the data radio bearer DRB for transmitting small packet data and the DRB for transmitting large packet data.

22. The method of claim 19, wherein the logical channel corresponding to the first SR is a logical channel included in a first DRB, the first DRB is a DRB for transmitting small packet data, the logical channel corresponding to the second SR is a logical channel included in a second DRB, and the second DRB is a DRB for transmitting large packet data.

23. A data transmission method, applied to a network device, the method comprising:

the network equipment and the terminal in the non-connection state carry out a packet data transmission process; the packet data transmission process comprises the steps that the network equipment receives a random access preamble, a first data packet and an RRC request message sent by the terminal, and the network equipment sends an RRC response message to the terminal; the first data packet is packet data obtained by the terminal;

the network equipment receives a first BSR sent by the terminal, wherein the first BSR is sent by the terminal when a second data packet is packet data, and the second data packet is obtained by the terminal in the packet data transmission process;

the network device scheduling a first transmission resource for the terminal in response to the first BSR;

24. The method of claim 23, wherein the first BSR includes a first field indicating transmission resources for acquiring small packet data, and wherein the first BSR includes a second field indicating transmission resources for acquiring large packet data.

25. The method of claim 24, wherein the first field indicates a first logical channel group including logical channels for transmitting small packet data, and wherein the second field indicates a second logical channel group including logical channels for transmitting large packet data.

26. A data transmission method, applied to a network device, the method comprising:

the network equipment receives a random access preamble sent by the terminal, wherein the random access preamble is sent after the terminal obtains a first data packet, and the first data packet is packet data;

the network equipment receives a third data packet, an RRC request message and first indication information sent by the terminal, wherein the first indication information is sent after the terminal obtains a second data packet, and the second data packet is packet data obtained when or after the terminal sends the random access preamble to the network equipment; the third data packet is a data packet with higher priority in the first data packet and the second data packet;

the network equipment responds to the first indication information to schedule first transmission resources for the terminal;

27. A user equipment comprising a transceiver, a processor and a memory for storing a computer program, the processor invoking the computer program for performing the method of any one of claims 1-17.

28. A network device comprising a transceiver, a processor and a memory for storing a computer program, the processor invoking the computer program for performing the method of any one of claims 18-26.

29. A computer storage medium, characterized in that the computer storage medium stores a computer program which, when executed by a processor, implements the method of any of claims 1-17 or the method of any of claims 18-26.