WO2023226662A1

WO2023226662A1 - Communication method, communication apparatus and communication system

Info

Publication number: WO2023226662A1
Application number: PCT/CN2023/090307
Authority: WO
Inventors: 单宝堃
Original assignee: 荣耀终端有限公司
Priority date: 2022-05-26
Filing date: 2023-04-24
Publication date: 2023-11-30
Also published as: CN117202373A

Abstract

The present application relates to the field of communications. Disclosed are a communication method, a communication apparatus and a communication system, which are used for reducing the power consumption and transmission delay of a terminal device. The communication method, which is applied to an access network device, comprises: sending feedback indication information to a terminal device, wherein the feedback indication information is used for indicating whether the terminal device performs hybrid automatic repeat request (HARQ) feedback for downlink data and/or downlink signaling of a mobile terminate small data transmission (MT-SDT) service; receiving the downlink data or downlink signaling from a core network element, and sending the downlink data or downlink signaling to the terminal device in a radio resource control (RRC) inactive state; and only when the feedback indication information indicates that the terminal device performs HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, receiving, from the terminal device, the HARQ feedback for the downlink data or downlink signaling.

Description

Communication method, communication device and communication system

This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on May 26, 2022, with application number 202210582947.2 and the application name "Communication method, communication device and communication system", the entire content of which is incorporated herein by reference. Applying.

Technical field

The present application relates to the field of communication, and in particular, to a communication method, communication device and communication system.

Background technique

In traditional cellular network communications (such as communications between mobile phones and access network equipment), hybrid automatic repeat request (HARQ) feedback is generally used to ensure the reliability of data transmission. However, in the mobile terminal (i.e. called) small data transmission (MT-SDT) business, scenarios that do not require high reliability are common, such as downlink periodic signaling and sensors in the Internet of Things. positioning instructions, etc. In this scenario with low reliability requirements, HARQ feedback by the terminal equipment will increase the power consumption of the terminal equipment and the transmission delay of the MT-SDT service.

Contents of the invention

Embodiments of the present application provide a communication method, communication device and communication system for reducing the power consumption and transmission delay of terminal equipment.

In order to achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

In a first aspect, a communication method is provided, which is applied to access network equipment. The method includes: sending feedback indication information to a terminal equipment, and the feedback indication information is used to indicate to the terminal equipment: whether to transmit MT-SDT service for mobile terminal small data Perform hybrid automatic repeat request HARQ feedback on the downlink data and/or downlink signaling; receive downlink data or downlink signaling from the core network element, and send downlink data or downlink signaling to the terminal device in the radio resource control RRC inactive state Order; receive HARQ feedback for downlink data or downlink signaling from the terminal device only when the feedback indication information indicates that the terminal device performs HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service.

In the communication method provided by the embodiment of the present application, the access network device sends feedback indication information to the terminal device. The feedback indication information instructs the terminal device whether to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service. When the When the feedback indication information indicates that the terminal device does not perform HARQ feedback, the terminal device does not perform HARQ feedback for the downlink data or downlink signaling of the MT-SDT service, and the MT-SDT service can end as soon as possible (the access network device sends the RRC release message as soon as possible), This reduces the power consumption of terminal equipment and the transmission delay of MT-SDT services.

In a possible implementation, the method further includes: receiving feedback indication information from the core network element. That is, the core network element and the terminal device negotiate to determine the feedback indication information.

In a possible implementation, the method further includes: receiving feedback tendency information from the terminal device, where the feedback tendency information is used to indicate whether the terminal device is inclined to perform HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service; according to The feedback tendency information determines the feedback instruction information, or sends the feedback tendency information to the core network element, and the feedback tendency information is used by the core network element to determine the feedback instruction information. That is, the access network equipment can The feedback tendency information determines the feedback instruction information, or the core network element determines the feedback instruction information based on the feedback tendency information.

In a possible implementation, if the feedback tendency information indicates that the terminal equipment prefers not to perform HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service, then the feedback indication information indicates that the terminal equipment does not perform HARQ feedback for the MT-SDT service. HARQ feedback is not performed on downlink data and/or downlink signaling; or, if the feedback tendency information indicates that the terminal equipment tends to perform HARQ feedback on the downlink data and/or downlink signaling of the MT-SDT service, the feedback indication information instructs the terminal equipment on HARQ feedback is performed on the downlink data and/or downlink signaling of the MT-SDT service. For example, for MT-SDT services with low reliability requirements such as the transmission of downlink heartbeat packets, the feedback tendency information indicates that the terminal equipment tends not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service to reduce the risk of the terminal equipment. Power consumption; for MT-SDT services with high reliability requirements such as transmission of downlink data and/or downlink signaling, the feedback tendency information indicates that the terminal equipment tends to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service , thereby ensuring reliable transmission of downlink data and/or downlink signaling.

In a possible implementation, the feedback indication information is carried in a paging message, or in a random access response message, or in downlink control information for scheduling downlink data or downlink signaling, or in the RRC release message. The messages carrying feedback indication information can be flexible.

In a possible implementation, the feedback indication information is associated with a signaling resource bearer that transmits downlink signaling, or the feedback indication information is associated with a data resource bearer that transmits downlink data. That is, feedback indication information can be configured for each signaling resource bearer or data resource bearer, making the configuration more flexible.

In a second aspect, a communication method is provided, which is applied to a terminal device. The method includes: receiving feedback indication information from an access network device. The feedback indication information is used to instruct the terminal device: whether to transmit MT-SDT service for mobile terminal small data. Perform hybrid automatic repeat request HARQ feedback on the downlink data and/or downlink signaling; when in the radio resource control RRC inactive state, receive downlink data or downlink signaling from the access network device; only when the feedback indication information indicates that the terminal device When performing HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service, HARQ feedback for the downlink data or downlink signaling is sent to the access network device.

In a possible implementation, the method further includes: determining feedback tendency information according to the reliability requirements of the MT-SDT service. The feedback tendency information is used to indicate whether the terminal device is inclined to downlink data and/or downlink signaling of the MT-SDT service. To perform HARQ feedback; send feedback tendency information to the access network device, and the feedback tendency information is used to determine the feedback indication information.

In a possible implementation, if the feedback tendency information indicates that the terminal equipment prefers not to perform HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service, then the feedback indication information indicates that the terminal equipment does not perform HARQ feedback for the MT-SDT service. HARQ feedback is not performed on downlink data and/or downlink signaling; or, if the feedback tendency information indicates that the terminal equipment tends to perform HARQ feedback on the downlink data and/or downlink signaling of the MT-SDT service, the feedback indication information instructs the terminal equipment on Downlink data and/or downlink signaling of MT-SDT service are carried out HARQ feedback.

In a possible implementation, the method further includes: sending the reliability requirements of the MT-SDT service performed by the terminal equipment to the core network element through the access network equipment, and the reliability requirements are used for the core network element to determine the feedback indication information.

In a possible implementation, if the reliability requirement is low, the feedback indication information instructs the terminal device not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, so as to reduce the power consumption of the terminal device; or , if the reliability requirements are high, the feedback indication information instructs the terminal device to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, thereby ensuring reliable transmission of downlink data and/or downlink signaling.

In the third aspect, a communication method is provided, which is applied to core network elements. The method includes: determining feedback indication information. The feedback indication information is used to instruct the terminal device: whether to transmit downlink data of the MT-SDT service for mobile terminal small data. and/or downlink signaling to perform hybrid automatic retransmission to request HARQ feedback; send feedback indication information to the terminal equipment through the access network equipment, and send downlink data or downlink signaling to the terminal equipment, so that the terminal equipment: only when the feedback indication information Instruct the terminal equipment to send HARQ feedback for the downlink data or downlink signaling to the access network equipment when performing HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service.

In a possible implementation, determining the feedback indication information includes: receiving feedback tendency information from the terminal device through the access network device, where the feedback tendency information is used to indicate the downlink data and/or downlink of the terminal device for the MT-SDT service. Whether the signaling tends to perform HARQ feedback; the feedback indication information is determined based on the feedback tendency information.

In a possible implementation, determining the feedback indication information includes: receiving the reliability requirements of the MT-SDT service performed by the terminal equipment from the terminal equipment through the access network equipment; and determining the feedback indication information according to the reliability requirements.

In a possible implementation, the core network element is a user plane functional network element that sends downlink data, or the core network element is an access management functional network element that sends downlink signaling.

In the fourth aspect, a communication device is provided, including a processor and a transceiver. The transceiver is used to communicate with other communication devices. When the processor executes instructions, the method described in the first aspect and any of its implementation modes is implement.

In the fifth aspect, a communication device is provided, including a processor and a transceiver. The transceiver is used to communicate with other communication devices. When the processor executes instructions, the method described in the second aspect and any of its implementation modes is implement.

In a sixth aspect, a communication device is provided, including a processor and a transceiver. The transceiver is used to communicate with other communication devices. When the processor executes instructions, the method described in the third aspect and any of its implementation modes is implement.

In a seventh aspect, a computer-readable storage medium is provided, including instructions. When the instructions are run on a communication device, the communication device causes the communication device to perform the method described in the first aspect and any of its implementation modes, or to perform the method as described in the first aspect and any embodiment thereof. The method described in the second aspect and any embodiment thereof, or the method described in the third aspect and any embodiment thereof is performed.

An eighth aspect provides a computer program product containing instructions. When the instructions are run on the above-mentioned communication device, the communication device causes the communication device to execute the method described in the first aspect and any of its implementation modes, or to execute the method as described in the first aspect and any embodiment thereof. The method described in the second aspect and any embodiment thereof, or the method described in the third aspect and any embodiment thereof is performed.

A ninth aspect provides a chip system. The chip system includes a processor for supporting a communication device to implement the functions involved in the above first aspect and any of its embodiments, or to implement the above second aspect and any of its embodiments. The functions involved in one embodiment, or the functions involved in the third aspect and any of its embodiments are realized. In a possible design, the device further includes an interface circuit, which can be used to receive signals from other devices (such as a memory) or to send signals to other devices (such as a communication interface). The chip system may include chips and may also include other discrete devices.

In a tenth aspect, a communication system is provided, including the communication device according to the fourth aspect, the communication device according to the fifth aspect, and the communication device according to the sixth aspect.

For the technical effects of the fourth aspect to the tenth aspect, refer to the technical effects of the first aspect and any embodiment thereof to the third aspect and any embodiment thereof, which will not be repeated here.

Description of the drawings

Figure 1 is a schematic architectural diagram of a communication system provided by an embodiment of the present application;

Figure 2 is a schematic structural diagram of a terminal device provided by an embodiment of the present application;

Figure 3 is a schematic structural diagram of an access network device provided by an embodiment of the present application;

Figure 4 is a schematic structural diagram of a network device provided by an embodiment of the present application;

Figure 5 is a schematic flow chart of a communication method provided by an embodiment of the present application;

Figure 6 is a schematic flow chart of another communication method provided by an embodiment of the present application;

Figure 7 is a schematic flow chart of another communication method provided by an embodiment of the present application;

Figure 8 is a schematic flow chart of yet another communication method provided by an embodiment of the present application;

Figure 9 is a schematic flowchart of yet another communication method provided by an embodiment of the present application;

Figure 10 is a schematic flowchart of yet another communication method provided by an embodiment of the present application;

Figure 11 is a schematic flow chart of yet another communication method provided by an embodiment of the present application;

Figure 12 is a schematic flow chart of yet another communication method provided by an embodiment of the present application;

Figure 13 is a schematic flow chart of yet another communication method provided by an embodiment of the present application;

Figure 14 is a schematic structural diagram of a communication device provided by an embodiment of the present application;

Figure 15 is a schematic structural diagram of a chip system provided by an embodiment of the present application.

Detailed ways

It should be noted that the terms "first", "second", etc. involved in the embodiments of this application are only used for the purpose of distinguishing features of the same type and cannot be understood as indicating relative importance, quantity, order, etc.

The terms “exemplary” or “for example” used in the embodiments of this application are used to represent examples, illustrations or descriptions. Any embodiment or design described herein as "exemplary" or "such as" is not intended to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the words "exemplary" or "such as" is intended to present the concept in a concrete manner.

Figure 1 shows a schematic diagram of the fifth generation (5G) network architecture. Among them, Figure 1 takes the network service architecture of the 5G system as an example to show the interactive relationship between network functions and entities and the corresponding interfaces. The 3rd generation partnership project (3GPP) of the 5G system is based on services The network functions and entities included in the network architecture (service-based architecture, SBA) mainly include: terminal equipment (also called user equipment (UE)) 101, access network (AN)/wireless access network (radio access network, RAN) device 102, user plane function (UPF) network element 103, data network (DN) 104, access management function (AMF) network element 105, session Management function (session management function, SMF) network element 106, authentication server function (AUSF) network element 107, policy control function (PCF) network element 108, application function (AF) network Element 109, network slice selection function (NSSF) network element 110, unified data management (UDM) network element 111, network exposure function (NEF) network element 112 and network storage function (network repository function, NRF) network element 113.

A network function network element can be a network element running on proprietary hardware, a software instance running on proprietary hardware, or a virtual function instantiated on a suitable platform, such as a cloud infrastructure.

The following is a detailed introduction to the main functions of each device.

AN/RAN equipment 102: The AN/RAN equipment 102 may include various forms of base stations, such as: macro base stations, micro base stations (also called "small stations"), distributed unit-control unit (DU) -CU) etc. In addition, the above-mentioned base station can also be a wireless controller in a cloud radio access network (CRAN) scenario, or a relay station, access point, vehicle-mounted device, wearable device or future evolved public land mobile network (public land mobile network). Network equipment in land mobile network (PLMN) network, etc. AN/RAN can also include broadband network gateway (BNG), aggregation switches, non-3GPP access equipment, etc.

The AN/RAN device 102 is mainly responsible for radio resource management, uplink and downlink data classification, and service quality on the air interface side. (quality of service, QoS) management, data compression and encryption, signaling processing with control plane network elements or data forwarding with user plane functional network elements, etc. The embodiments of this application do not limit the specific form and structure of AN/RAN. For example, in systems using different wireless access technologies, the names of devices with base station functions may be different. For example, the base station can be an evolved universal terrestrial radio access network (E-UTRAN) device in LTE, such as an evolved NodeB (eNB or e-NodeB), or it can be a 5G Next generation radio access network (NG-RAN) equipment in the system (such as gNB), etc.

UPF network element 103: Mainly responsible for packet routing and forwarding, as well as QoS processing of user plane data or accounting information statistics. The transmission resources and scheduling functions in the UPF network element 103 that provide services for UEs are managed and controlled by the SMF network element 106.

DN 104: DN 104 is the network used to transmit data. For example: DN 104 can be an operator service network, Internet access or third-party service network, etc.

For AMF network element 105, SMF network element 106, AUSF network element 107, PCF network element 108, AF network element 109, NSSF network element 110, UDM network element 111, NEF network element 112, NRF network element 113 and UDM network element 111 For the introduction of the functions of network elements, etc., you can refer to the explanations and descriptions in conventional technologies and will not be repeated here.

The terminal device 101 may be a device with a wireless transceiver function, and the terminal device 101 may be mobile or fixed. The terminal device 101 can be deployed on land (such as indoor or outdoor, handheld or vehicle-mounted, etc.), on water (such as ships, etc.), or in the air (such as aircraft, balloons, satellites, etc.). The terminal device 101 may be a user equipment (UE), an access terminal, a terminal unit, a subscriber unit (subscriber unit), or a terminal station in a 5G network or a future evolved public land mobile network (PLMN). , mobile station (MS), mobile station, remote station, remote terminal, mobile equipment, wireless communication equipment, terminal agent or terminal device, etc. For example, the terminal device 101 can be a mobile phone, a tablet computer, a laptop, a smart bracelet, a smart watch, a headset, a smart speaker, a virtual reality (VR) device, an augmented reality (AR) device, an industrial control ( Wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in remote medical, wireless terminals in smart grid, and transportation safety Wireless terminals, wireless terminals in smart cities, wireless terminals in smart homes, etc. The embodiment of the present application does not limit the specific type and structure of the terminal device 101.

The following describes the structures of the terminal equipment 101, the access network equipment (ie, AN/RAN equipment) 102, and the network equipment in the core network (for example, the AMF network element and the UPF network element).

Taking the terminal device 101 as a mobile phone as an example, FIG. 2 shows a possible structure of the terminal device 101. The terminal device 101 may include a processor 210, an external memory interface 220, an internal memory 221, a universal serial bus (USB) interface 230, a power management module 240, a battery 241, a wireless charging coil 242, an antenna 1, an antenna 2. Mobile communication module 250, wireless communication module 260, audio module 270, speaker 270A, receiver 270B, microphone 270C, headphone interface 270D, sensor module 280, button 290, motor 291, indicator 292, camera 293, display screen 294 and Subscriber identification module (SIM) card interface 295, etc.

The sensor module 280 may include a pressure sensor, a gyroscope sensor, an air pressure sensor, a magnetic sensor, sensors, acceleration sensors, distance sensors, proximity light sensors, fingerprint sensors, temperature sensors, touch sensors, ambient light sensors, bone conduction sensors, etc.

It can be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on the terminal device 101. In other embodiments of the present application, the terminal device 101 may include more or less components than shown in the figures, or combine some components, or split some components, or arrange different components. The components illustrated may be implemented in hardware, software, or a combination of software and hardware.

The processor 210 may include one or more processing units. For example, the processor 210 may include a central processing unit (CPU), an application processor (AP), a modem processor, a graphics processor ( graphics processing unit (GPU), image signal processor (ISP), controller, memory, video codec, digital signal processor (DSP), baseband processor, and neural network processor ( neural-network processing unit, NPU), etc. Among them, different processing units can be independent devices or integrated in one or more processors. For example, processor 210 may be an application processor AP. Alternatively, the above-mentioned processor 210 can be integrated in a system on chip (SoC). Alternatively, the above-mentioned processor 210 may be integrated in an integrated circuit (IC) chip. The processor 210 may include an analog front end (AFE) and a micro-controller unit (MCU) in an IC chip.

Among them, the controller may be the nerve center and command center of the terminal device 101. The controller can generate operation control signals based on the instruction operation code and timing signals to complete the control of fetching and executing instructions.

The processor 210 may also be provided with a memory for storing instructions and data. In some embodiments, the memory in processor 210 is cache memory. This memory may hold instructions or data that have been recently used or recycled by processor 210 . If the processor 210 needs to use the instructions or data again, it can be called directly from the memory. Repeated access is avoided and the waiting time of the processor 210 is reduced, thus improving the efficiency of the system.

In some embodiments, processor 210 may include one or more interfaces. Interfaces can include integrated circuit (inter-integrated circuit, I2C) interface, integrated circuit built-in audio (inter-integrated circuit sound, I2S) interface, pulse code modulation (pulse code modulation, PCM) interface, universal asynchronous receiver and transmitter (universal asynchronous receiver/transmitter (UART) interface, mobile industry processor interface (MIPI), general-purpose input/output (GPIO) interface, subscriber identity module (subscriber identity module, SIM) interface and/ Or USB interface, etc.

It can be understood that the interface connection relationship between the modules illustrated in the embodiment of the present invention is only a schematic explanation and does not constitute a structural limitation on the terminal device 101. In other embodiments of the present application, the terminal device 101 may also adopt different interface connection methods in the above embodiments, or a combination of multiple interface connection methods.

The power management module 240 is used to receive charging input from the charger. The charger may be a wireless charger (such as a wireless charging base of the terminal device 101 or other devices that can wirelessly charge the terminal device 101), or a wired charger. For example, the power management module 240 may receive charging input from a wired charger through the USB interface 230 . The power management module 240 may receive wireless charging input through the wireless charging coil 242 of the electronic device.

The power management module 240 can also provide power for electronic devices while charging the battery 241 . The power management module 240 receives input from the battery 241 and supplies power to the processor 210, internal memory 221, external memory interface 220, display screen 294, camera 293, wireless communication module 260, etc. The power management module 240 is ok Used to monitor the battery capacity, battery cycle times, battery health status (leakage, impedance) and other parameters of the battery 241. In some other embodiments, the power management module 240 may also be provided in the processor 210 .

The wireless communication function of the terminal device 101 can be implemented through the antenna 1, the antenna 2, the mobile communication module 250, the wireless communication module 260, the modem processor and the baseband processor.

Antenna 1 and Antenna 2 are used to transmit and receive electromagnetic wave signals. Each antenna in terminal device 101 may be used to cover a single or multiple communication frequency bands. Different antennas can also be reused to improve antenna utilization. For example: Antenna 1 can be reused as a diversity antenna for a wireless LAN. In other embodiments, antennas may be used in conjunction with tuning switches.

The mobile communication module 250 can provide wireless communication solutions including 2G/3G/4G/5G applied on the terminal device 101. The wireless communication module 260 can provide applications on the terminal device 101 including wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) network), Bluetooth (bluetooth, BT), global navigation satellites Wireless communication solutions such as global navigation satellite system (GNSS), frequency modulation (FM), near field communication (NFC), infrared technology (infrared, IR), etc. In some embodiments, the antenna 1 of the terminal device 101 is coupled to the mobile communication module 250, and the antenna 2 is coupled to the wireless communication module 260, so that the terminal device 101 can communicate with the network and other devices through wireless communication technology.

The terminal device 101 implements display functions through a GPU, a display screen 294, an application processor, and the like. The GPU is an image processing microprocessor and is connected to the display screen 294 and the application processor. GPUs are used to perform mathematical and geometric calculations for graphics rendering. Processor 210 may include one or more GPUs that execute program instructions to generate or alter display information.

The display screen 294 is used to display images, videos, etc. Display 294 includes a display panel. In some embodiments, the terminal device 101 may include 1 or N display screens 294, where N is a positive integer greater than 1.

The terminal device 101 can realize the shooting function through the ISP, camera 293, video codec, GPU, display screen 294, application processor, etc. The ISP is used to process the data fed back by the camera 293. In some embodiments, the ISP may be provided in the camera 293. Camera 293 is used to capture still images or video. In some embodiments, the terminal device 101 may include 1 or N cameras 293, where N is a positive integer greater than 1.

The external memory interface 220 can be used to connect an external memory card, such as a micro SanDisk (Micro SD) card, to expand the storage capacity of the terminal device 101. The external memory card communicates with the processor 210 through the external memory interface 220 to implement the data storage function. Such as saving music, videos, etc. files in external memory card.

Internal memory 221 may be used to store computer executable program code, which includes instructions. The processor 210 executes instructions stored in the internal memory 221 to execute various functional applications and data processing of the terminal device 101 . In addition, the internal memory 221 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, universal flash storage (UFS), etc.

The terminal device 101 can implement audio functions through the audio module 270, the speaker 270A, the receiver 270B, the microphone 270C, the headphone interface 270D, and the application processor. Such as music playback, recording, etc.

The audio module 270 is used to convert digital audio information into analog audio signal output, and is also used to convert analog audio input into digital audio signals. In some embodiments, the audio module 270 may be provided in the processor 210 , or some functional modules of the audio module 270 may be provided in the processor 210 . Speaker 270A, also called "speaker", Used to convert audio electrical signals into sound signals. Receiver 270B, also called "earpiece", is used to convert audio electrical signals into sound signals. Microphone 270C, also called "microphone" or "microphone", is used to convert sound signals into electrical signals. The terminal device 101 may be provided with at least one microphone 270C. The headphone interface 270D is used to connect wired headphones. The headphone interface 270D may be a USB interface 230, or may be a 3.5 mm open mobile terminal platform (OMTP) standard interface or a Cellular Telecommunications Industry Association of the USA (CTIA) standard interface.

The buttons 290 include a power button, a volume button, etc. Key 290 may be a mechanical key. It can also be a touch button. The terminal device 101 can receive key input and generate key signal input related to user settings and function control of the terminal device 101 . The motor 291 can generate vibration prompts. The motor 291 can be used for vibration prompts for incoming calls and can also be used for touch vibration feedback. The indicator 292 may be an indicator light, which may be used to indicate charging status, power changes, or may be used to indicate messages, missed calls, notifications, etc. The SIM card interface 295 is used to connect a SIM card. The SIM card can be inserted into the SIM card interface 295 or pulled out from the SIM card interface 295 to achieve contact and separation from the terminal device 101 . The terminal device 101 can support 1 or N SIM card interfaces, where N is a positive integer greater than 1. The SIM card interface 295 can support SIN (Nano SIM) cards, micro SIM (Micro SIM) cards, SIM cards, etc. In some embodiments, the terminal device 101 uses an embedded SIM (eSIM) card. The eSIM card can be embedded in the terminal device 101 and cannot be separated from the terminal device 101.

Figure 3 shows a possible structure of the access network device 102. The access network device 102 includes a baseband processing unit (baseband unit, BBU) 301, a remote radio unit (remote radio unit, RRU) 302 and an antenna 303 connection , BBU 301 and RRU 302 can be disassembled and used as needed. Among them, the BBU 301 may include a processor 331, a memory 332, and a bus system 333. The processor 331 and the memory 332 of the BBU 301 are connected to each other through the bus system 333. The above-mentioned bus system may be a peripheral component interconnection standard bus or an extended industry standard structure bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of presentation, only one line is used in the figure, but it does not mean that there is only one bus or one type of bus. The RRU 302 may include an RF circuit 334, the RF circuit 334 and the BBU 301 are connected to each other through optical fibers, and the RF circuit 334 and the antenna 303 are connected to each other through a coaxial cable.

Figure 4 shows a possible structure of a network device 400 (such as an AMF network element and a UPF network element) in the core network. The network device 400 may include at least one processor 401, a communication line 402, a memory 403 and at least one communication Interface 404. Communication line 402 may include a path that carries information between the above-mentioned components. The communication interface 404 uses any device such as a transceiver to communicate with other network equipment or access network equipment.

The processor involved in the embodiment of this application may be a chip. For example, it can be a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on chip (SoC), a central processor unit (CPU), Network processor (NP), digital signal processor (DSP), microcontroller unit (MCU), programmable logic device (PLD) or other integrated chips.

The memory involved in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory can be read-only memory (ROM), programmable ROM (PROM), erasable programmable read-only memory (erasable PROM, EPROM), electrically removable memory. Erase programmable read-only memory (electrically EPROM, EEPROM) or flash memory. Volatile memory may be random access memory (RAM), which is used as an external cache. By way of illustration, but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (double data rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous link dynamic random access memory (synchlink DRAM, SLDRAM) ) and direct memory bus random access memory (direct rambus RAM, DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

In the 5G new radio (NR) communication system, in order to improve the efficiency of frequent transmission of small data packets, the concept of RRC_INACTIVE State is introduced at the radio resource control (RRC) level. In the RRC inactive state, the RRC context of the terminal device is suspended on the terminal device side and the access network device side. When there is downlink data or downlink signaling on the network side that needs to be sent to the terminal device, The network side must first instruct the terminal device to trigger the RRC recovery request (RRC_ResumeRequest) process to move from the RRC inactive state to the RRC connected state (RRC_CONNECTED state), and then the terminal device can receive downlink data or downlink signaling from the network side.

However, for frequent small data packet transmission scenarios, the signaling overhead is still large. In response to this problem, MT-SDT was subsequently proposed, which allows terminal equipment to directly receive downlink data or downlink signaling in the RRC inactive state, avoiding entering the RRC connected state, thereby further reducing signaling overhead.

For MT-SDT, there are currently two technical solutions: the first is MT-SDT based on random access, which is further divided into MT-SDT based on 4-step random access (Figure 5 (shown in Figure 6) and MT-SDT based on 2-step random access (shown in Figure 6). The second type is MT-SDT based on configuration scheduling, which is further divided into: MT-SDT based on uplink configured grant (UL CG) (as shown in Figure 7) and MT-SDT based on downlink configured grant (UL CG). MT-SDT of DL CG) (as shown in Figure 8).

Specifically, as shown in Figure 5, the MT-SDT process based on 4-step random access includes S101-S109:

S101. The access network device sends random access resource information used in the MT-SDT process based on 4-step random access through a system broadcast message.

The random access resource information used in the MT-SDT process based on 4-step random access includes the MT-SDT-specific preamble and random access channel (RACH) resource information based on 4-step random access. .

The terminal device in the RRC inactive state receives the system broadcast message and obtains the above random access resources.

S102. The core network element sends the downlink data or downlink signaling of the MT-SDT service to the access network device.

Specifically, the AMF network element sends the downlink signaling of the MT-SDT service to the access network device, or the UPF network element sends the downlink data of the MT-SDT service to the access network device.

S103. The access network device sends a paging message to the terminal device to page the terminal device.

The paging message includes the identification of the terminal device and the paging cause, where the paging cause is MT-SDT.

S104. The terminal device in the RRC inactive state sends message 1 to the access network device through RACH resources. (Msg1).

After receiving the paging message, the terminal device in the RRC inactive state initiates the MT-SDT process based on 4-step random access through message 1 (Msg1), and sends the RRC recovery request (RRC_ResumeRequest) message to the access network device. , Message 1 (Msg1) includes a preamble dedicated to MT-SDT based on 4-step random access. Optionally, if there is uplink data, the terminal device in the RRC inactive state can also multiplex the uplink data and the RRC recovery request (RRC_ResumeRequest) message together and send it to the access network device.

It should be noted that message 1 (Msg1) includes a dedicated preamble for MT-SDT based on 4-step random access. This preamble is different from the traditional random access preamble to facilitate access. The network access device provides uplink scheduling (UL grant) for scheduling more uplink resources in message 2 (Msg2) for the terminal device to transmit the RRC recovery request (RRC_ResumeRequest) message (message 3 (Msg3)).

S105. The access network device sends a random access response (RAR) message (message 2 (Msg2)) to the terminal device.

The RAR message includes uplink scheduling (UL grant), which is used to indicate the uplink resources for transmitting the RRC recovery request (RRC_ResumeRequest) message (Message 3 (Msg3)).

S106. The terminal device sends an RRC recovery request (RRC_ResumeRequest) message (Message 3 (Msg3)) to the access network device on the PUSCH resource indicated by the uplink scheduling (UL grant).

S107. The access network device sends downlink data or downlink signaling of the MT-SDT service to the terminal device.

Optionally, the access network device can send downlink data or downlink signaling of the MT-SDT service to the terminal device through message 4 (Msg4).

S108. The terminal device performs HARQ feedback according to the reception status of downlink data or downlink signaling.

If the downlink data or downlink signaling is successfully received, a HARQ acknowledgment (ACK) is sent to the access network device; otherwise, if the downlink data or downlink signaling is not successfully received, a HARQ denial (non- acknowledge, NACK).

Thereafter, the terminal device begins to monitor the physical downlink control channel (PDCCH) in order to perform at least one of the following: if the terminal device feeds back a NACK, monitor whether there is retransmission of downlink data or downlink signaling. Monitor possible new transmissions of downlink data or downlink signaling (i.e. new downlink data or downlink signaling). Monitor the scheduling of the RRC release (RRCRelease) message in order to receive the RRC release (RRCRelease) message.

S109. The access network device sends an RRC release (RRCRelease) message to the terminal device to terminate the MT-SDT process.

The access network device can continue to configure the terminal device to enter the RRC inactive state, or it can configure the terminal device to enter the idle (IDLE) state. In addition, the RRC release (RRCRelease) message may be sent to the terminal device together with the downlink data or downlink signaling (for example, through message 4 (Msg4)) in step S107.

As shown in Figure 6, the MT-SDT process based on 2-step random access includes steps S201-S207:

S201. The access network device sends random access resource information used in the MT-SDT process based on 2-step random access through a system broadcast message.

Random access resource information based on 2-step random access includes MT-SDT dedicated preamble and PUSCH resource information based on 2-step random access, where the PUSCH resource information includes, for example, codeword information, Time domain position, frequency domain position, etc.

The terminal device in the RRC inactive state receives the system broadcast message and obtains random access resources.

S202. The core network element sends downlink data or downlink signaling of the MT-SDT service to the access network device.

S203. The access network device sends a paging message to the terminal device to page the terminal device.

S204. The terminal device in the RRC inactive state sends message A (MsgA) to the access network device through PUSCH resources.

After receiving the paging message, the terminal device in the RRC inactive state initiates the MT-SDT process based on 2-step random access through message A (MsgA), and sends the RRC recovery request (RRC_ResumeRequest) message to the access network device. . Optionally, if there is uplink data, the terminal device in the RRC inactive state can also multiplex the uplink data and the RRC recovery request (RRC_ResumeRequest) message and send it to the access network device.

It should be noted that message A (MsgA) includes an MT-SDT dedicated preamble based on 2-step random access and an RRC recovery request (RRC_ResumeRequest) message.

S205. The access network device sends downlink data or downlink signaling of the MT-SDT service to the terminal device.

Optionally, the access network device can send downlink data or downlink signaling of the MT-SDT service to the terminal device through message B (MsgB).

S206. The terminal device performs HARQ feedback according to the reception status of downlink data or downlink signaling.

For this step, refer to step S108, which will not be described again here.

S207. The access network device sends an RRC release (RRCRelease) message to the terminal device to terminate the MT-SDT process.

The access network device can continue to configure the terminal device to enter the RRC inactive state, or it can configure the terminal device to enter the idle (IDLE) state. In addition, the RRC release (RRCRelease) message may be sent to the terminal device together with downlink data or downlink signaling (optionally, through message B (MsgB)) in step S205.

As shown in Figure 7, the MT-SDT process based on UL CG includes steps S301-S307:

S301. The access network device sends an RRC release (RRCRelease) message to the terminal device in the RRC connected state.

The RRC release (RRCRelease) message is used to release the RRC connection state. The RRC release (RRCRelease) message includes UL CG configuration, such as uplink scheduling (UL grant), resource cycle, etc. Among them, the UL CG resources indicated by the UL CG configuration can only be used in the current cell.

The terminal device receives the RRC release (RRCRelease) message and enters the RRC inactive state.

S302. The core network element sends the downlink data or downlink signaling of the MT-SDT service to the access network device.

S303. The access network device sends a paging message to the terminal device to page the terminal device.

The paging message includes the identification of the terminal device and the paging reason, where the paging reason is MT-SDT.

S304. If there are UL CG resources indicated by the UL CG configuration in the current cell, the terminal device in the RRC inactive state sends an RRC recovery request (RRC_ResumeRequest) message to the access network device according to the UL CG configuration.

After receiving the paging message, the terminal device in the RRC inactive state initiates the MT-SDT process based on the UL CG through the RRC recovery request (RRC_ResumeRequest) message. For example, the terminal device in the RRC inactive state configures the Send an RRC recovery request (RRC_ResumeRequest) message to the access network device on the indicated PUSCH resource. Optionally, if there is uplink data, the terminal device in the RRC inactive state can also multiplex the uplink data and the RRC recovery request (RRC_ResumeRequest) message on the PUSCH resource indicated by the UL CG configuration and send them to the access network device together.

S305. The access network device schedules the physical downlink shared channel (PDSCH) resources through the downlink control information (DCI) in the PDCCH, and sends the downlink MT-SDT service to the terminal device on the PDSCH resources. data or downlink signaling.

S306. The terminal device performs HARQ feedback according to the reception status of downlink data or downlink signaling.

For this step, refer to step S108, which will not be described again here.

S307. The access network device sends an RRC release (RRCRelease) message to the terminal device to terminate the MT-SDT process.

The access network device can continue to configure the terminal device to enter the RRC inactive state, or it can configure the terminal device to enter the idle (IDLE) state. In addition, the RRC release (RRCRelease) message may be sent to the terminal device together with the downlink data or downlink signaling on the PDSCH resource in step S305.

As shown in Figure 8, the MT-SDT process based on DL CG includes steps S401-S407:

S401. The access network device sends an RRC release (RRCRelease) message to the terminal device in the RRC connected state.

The RRC release (RRCRelease) message is used to release the RRC connection state. The RRC release (RRCRelease) message includes DL CG configuration, such as downlink scheduling (DL grant), resource cycle, etc. Among them, the DL CG resources indicated by the DL CG configuration can only be used in the current cell.

S402. The core network element sends the downlink data or downlink signaling of the MT-SDT service to the access network device.

S403. The access network device sends a paging message to the terminal device to page the terminal device.

S404. The access network device sends the downlink data or downlink signaling of the MT-SDT service to the terminal device on the PDSCH resource indicated by the DL CG configuration.

Correspondingly, the terminal equipment in the RRC inactive state receives downlink data or downlink signaling from the access network equipment on the PDSCH resources indicated by the DL CG configuration.

S405. The terminal device performs HARQ feedback according to the reception status of downlink data or downlink signaling.

For this step, refer to step S108, which will not be described again here.

S406. The access network device sends an RRC release (RRCRelease) message to the terminal device to terminate the MT-SDT process.

The access network device can continue to configure the terminal device to enter the RRC inactive state, or it can configure the terminal device to enter the idle (IDLE) state. In addition, the RRC release (RRCRelease) message may be sent to the terminal device together with the downlink data or downlink signaling on the PDSCH resource in step S404.

From the various MT-SDT processes shown in Figures 5 to 8 above, the terminal equipment will perform HARQ feedback (ACK/NACK) after receiving downlink data or downlink signaling. As mentioned above, for MT-SDT services, scenarios with low reliability requirements are common. In such scenarios with low reliability requirements, HARQ feedback by terminal equipment will increase power consumption and transmission delay. Therefore, for the MT-SDT service, the terminal equipment and the access network equipment can negotiate to disable the HARQ feedback function to reduce the performance of the terminal equipment. It should be noted that the HARQ feedback disabling function provided by this application can be applied not only to MT-SDT scenarios, but also to other downlink transmission scenarios to save uplink feedback resources and reduce the power consumption of terminal equipment.

To this end, embodiments of the present application provide a communication method. For the MT-SDT process based on 4-step random access, the core network element (such as AMF network element, UPF network element) determines whether the terminal device performs HARQ feedback and Notify the access network device, and then the access network device instructs the terminal device whether to perform HARQ feedback. As shown in Figure 9, the method includes steps S501-S511:

S501. The core network element (for example, the AMF network element, the UPF network element) determines the feedback indication information.

The feedback indication information is used to indicate whether the terminal equipment performs HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service.

In a possible implementation, the core network element can determine the feedback indication information through negotiation with the terminal device.

For example, the core network element can obtain the registration information, contract information and other information of the terminal equipment from where it comes from, any of which information can include the reliability requirements of the MT-SDT service performed by the terminal equipment, and then the core network element can perform operations based on the terminal equipment. The reliability of the MT-SDT service requires determining the feedback indication information.

For MT-SDT services with high reliability requirements, the core network element determines the feedback indication information to instruct the terminal device to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service; for MT-SDT with low reliability requirements service, the core network element determines that the feedback indication information instructs the terminal device not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service.

For another example, the core network element may receive feedback tendency information from the terminal device through the access network device, and determine the feedback indication information based on the feedback tendency information. The feedback tendency information is used to instruct the terminal device for the downlink data and/or the MT-SDT service. Or whether the downlink signaling tends to perform HARQ feedback. For example, the terminal device at this time may be in the RRC connected state. The terminal device understands the reliability requirements of the MT-SDT service it performs, and the terminal device can determine the feedback tendency information based on the reliability requirements of the MT-SDT service it performs. For example, for MT-SDT services with low reliability requirements such as the transmission of downlink heartbeat packets, the feedback tendency information indicates that the terminal equipment tends not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service to reduce the risk of the terminal equipment. Power consumption; for MT-SDT services with high reliability requirements such as the transmission of downlink control information, the feedback tendency information indicates that the terminal equipment tends to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, thereby ensuring the downlink data and/or reliable transmission of downlink signaling.

If the feedback tendency information indicates that the terminal equipment prefers downlink data and/or downlink signaling for the MT-SDT service, If the feedback tendency information indicates that the terminal device does not perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, the core network element determines that the feedback indication information indicates that the terminal device does not perform HARQ feedback for the MT-SDT service. The downlink data and/or downlink signaling tend to perform HARQ feedback, then the core network element determines that the feedback indication information instructs the terminal device to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service.

In another possible implementation, the core network element can also obtain the usage status of network resources (such as physical uplink control channel (PUCCH) resources), such as the uplink feedback resources of the cell where the terminal device is located. The core network element can determine the feedback indication information based on the usage of the uplink feedback resources in the cell where the terminal device is located.

For example, if the usage ratio of the uplink feedback resources is greater than the threshold, the core network element determines that the feedback indication information instructs the terminal device not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service to save uplink feedback. resources, priority is given to ensuring HARQ feedback of services performed by the terminal equipment in the RRC connected state; otherwise, the core network element determines the feedback indication information to instruct the terminal equipment to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, To ensure reliable transmission of downlink data and/or downlink signaling.

It should be noted that "the core network element determines the feedback indication information based on the usage of the uplink feedback resources in the cell where the terminal device is located" and "the core network element determines the feedback indication information through negotiation with the terminal device" can also be combined The implementation methods are combined, and the two implementation methods can be set with different priorities. When the core network element obtains opposite feedback indication information through the two implementation methods, the feedback indication information determined by the implementation method with a higher priority is allow. For example, assume that the implementation method "the core network element determines the feedback indication information based on the usage of the uplink feedback resources in the cell where the terminal device is located" has a high priority, and "the core network element determines the feedback indication information through negotiation with the terminal device" This implementation has a low priority. When the core network element obtains opposite feedback indication information through these two implementations, the core network element determines the feedback indication based on the usage of the uplink feedback resources in the cell where the terminal device is located. The feedback indication information determined in this way shall prevail.

For example, if the usage ratio of the uplink feedback resources is greater than the threshold, the core network element determines that the feedback indication information instructs the terminal device not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service to save uplink feedback. resources, priority is given to ensuring HARQ feedback of services performed by terminal equipment in the RRC connected state; otherwise, the core network element determines the feedback indication information based on the feedback tendency information or the reliability requirements of the MT-SDT services performed by the terminal equipment. At this time, The feedback indication information may instruct the terminal device to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, or may instruct the terminal device not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service.

To sum up, the core network element can determine the feedback indication information based on the reliability requirements of the MT-SDT service performed by the terminal equipment, or the core network element can determine the feedback indication information based on the feedback tendency information, or the core network element can determine the feedback indication information based on the feedback tendency information. The feedback indication information can be determined based on the usage of uplink feedback resources in the cell where the terminal equipment is located, or the core network element can be based on the reliability requirements of the MT-SDT service performed by the terminal equipment and the usage of uplink feedback resources in the cell where the terminal equipment is located. Determine the feedback indication information, or the core network element may determine the feedback indication information based on the feedback tendency information and the usage of uplink feedback resources in the cell where the terminal device is located.

In addition, it should be noted that step S501 is optional:

In a possible implementation, step S501 can be performed, that is, the core network element (for example, the AMF network element, UPF network element) determines the feedback indication information; and in step S503, the core network element sends the feedback indication information to the access network device; so that in step S504, the access network device obtains the feedback indication from the core network element information.

In another possible implementation, step S501 may not be performed, and in step S503, the core network element does not send feedback indication information to the access network device; so that in step S504, the access network device determines by itself Feedback instructions.

S502. The access network device sends random access resource information used in the MT-SDT process based on 4-step random access through a system broadcast message.

This application does not limit the execution order of steps S501 and S502, that is, step S501 may be executed first and then step S502, or step S502 may be executed first and then step S501.

For other contents of this step, refer to step S101 and will not be described again here.

S503. The core network element sends the downlink data or downlink signaling of the MT-SDT service to the access network device.

Optionally, the core network element sends feedback indication information to the access network device.

When the core network element is an AMF network element, the AMF network element sends the downlink signaling of the MT-SDT service to the access network device, and the feedback indication information can be carried with the signaling resource bearer (SRB) that transmits the downlink signaling. Association, that is, feedback indication information can be configured for each SRB.

When the core network element is a UPF network element, the UPF network element sends the downlink data of the MT-SDT service to the access network equipment, and the feedback indication information can be associated with the data resource bearer (DRB) that transmits the downlink data, that is, Feedback indication information can be configured for each DRB.

S504. The access network device obtains feedback indication information.

In a possible implementation, if the core network element sends feedback indication information to the access network device, the access network device obtains the feedback indication information from the core network element.

In another possible implementation, if the core network element does not send feedback indication information to the access network device, the access network device may receive feedback tendency information from the terminal device and determine the feedback indication information based on the feedback tendency information. , specifically refer to the relevant description of "the core network element determines the feedback indication information based on the feedback tendency information" in step S501, which will not be described again here.

In another possible implementation, the access network device can obtain the usage status of network resources (such as PUCCH resources), such as the usage status of uplink feedback resources in the cell where the terminal device is located. The access network device can obtain the usage status of the network resources (such as PUCCH resources) according to the cell where the terminal device is located. The resource usage determines the feedback indication information. For details, refer to step S501 regarding "the core network element determines the feedback indication information based on the usage of the uplink feedback resource of the cell where the terminal device is located", which will not be described again here.

In addition, similar to step S501, "the access network device determines the feedback indication information based on the usage of the uplink feedback resources in the cell where the terminal device is located" and "the access network device determines the feedback indication information based on the feedback tendency information" can also be combined. Two implementations are combined, and the two implementations can be set with different priorities. When the core network element obtains opposite feedback indication information through these two implementations, the feedback indication information determined by the implementation with a higher priority is used. shall prevail.

For example, if the usage ratio of the uplink feedback resources is greater than the threshold, the access network device determines that the feedback indication information instructs the terminal device not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service to save uplink feedback. resources, priority is given to ensuring HARQ feedback of services performed by terminal equipment in the RRC connected state; otherwise, the access network equipment determines the feedback indication information based on the feedback tendency information. The feedback indication information at this time The terminal equipment may be instructed to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, or the terminal equipment may be instructed not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service.

To sum up, the access network equipment can determine the feedback indication information based on the feedback tendency information, or the access network equipment can determine the feedback indication information based on the usage of uplink feedback resources in the cell where the terminal equipment is located, or the access network equipment can determine the feedback indication information. The feedback indication information is determined based on the feedback tendency information and the usage of uplink feedback resources in the cell where the terminal equipment is located.

It should be noted that step S504 only needs to be executed before the access network device sends feedback instruction information to the terminal device.

S505: The access network device sends a paging message to the terminal device to page the terminal device.

Optionally, the access network device sends feedback indication information to the terminal device, and the feedback indication information may be carried in a paging message.

S506. The terminal device in the RRC inactive state sends message 1 (Msg1) to the access network device through RACH resources.

For this step, refer to step S104, which will not be described again here.

S507. The access network device sends a random access response (RAR) message (message 2 (Msg2)) to the terminal device.

Optionally, the access network device sends feedback indication information to the terminal device, and the feedback indication information can be carried in a RAR message.

For other contents of this step, refer to step S105 and will not be described again here.

S508. The terminal device sends an RRC recovery request (RRC_ResumeRequest) message (Message 3 (Msg3)) to the access network device on the PUSCH resource indicated by the uplink scheduling (UL grant).

S509. The access network device sends downlink data or downlink signaling of the MT-SDT service to the terminal device.

Optionally, the access network device sends feedback indication information to the terminal device, and the feedback indication information may be carried in DCI for scheduling downlink data or downlink signaling.

It should be noted that "the access network device sends feedback instruction information to the terminal device" can be performed in step S505, S507, or S509. That is, the feedback indication information may be carried in a paging message, or may be carried in a RAR message, or may be carried in DCI for scheduling downlink data or downlink signaling.

If the feedback indication information indicates HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, step S510 is executed; otherwise, step S510 is not executed, that is, step S510 is optional.

When step S510 is not performed, the terminal device starts to monitor the PDCCH in order to perform at least one of the following: monitor possible new transmission of downlink data or downlink signaling (ie, new downlink data or downlink signaling). Monitor the scheduling of the RRC release (RRCRelease) message in order to receive the RRC release (RRCRelease) message. When receiving the RRC release (RRCRelease) message, the terminal device switches to the RRC inactive state.

For other contents of step S509, refer to step S107, which will not be described again here.

S510. The terminal device performs HARQ feedback according to the reception status of downlink data or downlink signaling.

For this step, refer to step S108, which will not be described again here.

S511. The access network device sends an RRC release (RRCRelease) message to the terminal device to terminate the MT-SDT process.

For this step, refer to step S109, which will not be described again here.

The embodiment of this application provides another communication method. For the MT-SDT process based on 2-step random access, the core network element (such as AMF network element, UPF network element) determines whether the terminal device performs HARQ feedback and notifies The access network device then instructs the terminal device whether to perform HARQ feedback. As shown in Figure 10, the method includes steps S601-S609:

S601. The core network element (for example, the AMF network element, the UPF network element) determines the feedback indication information.

Similar to step S501, step S601 is optional:

In a possible implementation, step S601 can be performed, that is, the core network element (for example, AMF network element, UPF network element) determines the feedback indication information; and in step S603, the core network element sends the feedback instruction to the access network. The device sends feedback indication information; so that in step S604, the access network device obtains feedback indication information from the core network element.

In another possible implementation, step S601 may not be performed, and in step S603, the core network element does not send feedback indication information to the access network device; so that in step S604, the access network device determines by itself Feedback instructions.

For other contents of this step, refer to step S501 and will not be described again here.

S602. The access network device sends random access resource information used in the MT-SDT process based on 2-step random access through a system broadcast message.

For this step, refer to step S201, which will not be described again here. .

S603. The core network element sends the downlink data or downlink signaling of the MT-SDT service to the access network device.

For this step, refer to step S503, which will not be described again here.

S604. The access network device obtains feedback indication information.

For this step, refer to step S504, which will not be described again here.

S605: The access network device sends a paging message to the terminal device to page the terminal device.

S606. The terminal device in the RRC inactive state sends message A (MsgA) to the access network device through PUSCH resources.

For this step, refer to step S204, which will not be described again here.

S607. The access network device sends downlink data or downlink signaling of the MT-SDT service to the terminal device.

Optionally, the access network device sends feedback indication information to the terminal device, and the feedback indication information can be carried in the DCI of the scheduling message B (MsgB) (that is, it can be carried in the DCI of scheduling downlink data or downlink signaling).

It should be noted that "the access network device sends feedback instruction information to the terminal device" can be performed in step S605 or S607. That is, the feedback indication information may be carried in the paging message, or may be carried in the DCI of the scheduling message B (MsgB) (that is, it may be carried in the DCI of scheduling downlink data or downlink signaling).

If the feedback indication information indicates HARQ feedback, step S608 is executed; otherwise, step S608 is not executed, that is, step S608 is optional.

When step S608 is not performed, the terminal device starts to monitor the PDCCH in order to perform at least one of the following: monitor possible new transmission of downlink data or downlink signaling (ie, new downlink data or downlink signaling). Monitor the scheduling of the RRC release (RRCRelease) message in order to receive the RRC release (RRCRelease) message. When receiving the RRC release (RRCRelease) message, the terminal device switches to the RRC inactive state.

For other contents of step S607, refer to step S205, which will not be described again here.

S608: The terminal device performs HARQ feedback according to the reception status of downlink data or downlink signaling.

For this step, refer to step S108, which will not be described again here.

S609. The access network device sends an RRC release (RRCRelease) message to the terminal device to terminate the MT-SDT process.

For this step, refer to step S207, which will not be described again here.

Embodiments of the present application provide a communication method. For the MT-SDT process based on UL CG, the terminal device sends feedback tendency information to the access network device to indicate whether it is inclined to perform HARQ feedback, and the access network device instructs the terminal device Whether to perform HARQ feedback. As shown in Figure 11, the method includes steps S701-S709:

S701. The terminal device sends feedback tendency information to the access network device.

For example, at this time, the terminal device may be in the RRC connection state, and the terminal device may determine the feedback tendency information according to the reliability requirements of the ongoing MT-SDT service. For details, refer to the relevant description in step S501, which will not be described again here.

Step S701 is optional.

S702. The access network device obtains feedback indication information.

The access network device may determine the feedback indication information based on the feedback tendency information, or the access network device may determine the feedback indication information based on the usage of uplink feedback resources in the cell where the terminal device is located, or the access network device may determine the feedback indication information based on the feedback tendency information and The usage of uplink feedback resources in the cell where the terminal equipment is located determines the feedback indication information. It should be noted that if the access network device does not receive feedback tendency information from the terminal device, the access network device can directly determine the feedback indication information based on the usage of uplink feedback resources in the cell where the terminal device is located. For other contents of this step, refer to the relevant description in step S504 and will not be described again here.

S703. The access network device sends an RRC release (RRCRelease) message to the terminal device in the RRC connected state.

Optionally, the access network device sends feedback indication information to the terminal device, and the feedback indication information may be carried in an RRC release (RRCRelease) message.

For other contents of this step, refer to step S301 and will not be described again here.

S704. The core network element sends the downlink data or downlink signaling of the MT-SDT service to the access network device.

S705: The access network device sends a paging message to the terminal device to page the terminal device.

Optionally, the access network device sends feedback indication information to the terminal device, and the feedback indication information can be carried in the search paging message.

S706. If there are UL CG resources indicated by the UL CG configuration in the current cell, the terminal device in the RRC inactive state sends an RRC recovery request (RRC_ResumeRequest) message to the access network device according to the UL CG configuration.

For this step, refer to step S304, which will not be described again here.

S707. The access network device schedules PDSCH resources through the DCI in the PDCCH, and sends downlink data or downlink signaling of the MT-SDT service to the terminal device on the PDSCH resources.

Optionally, the access network device sends feedback indication information to the terminal device, and the feedback indication information can be carried in the DCI (that is, it can be carried in the DCI that schedules downlink data or downlink signaling).

If the feedback indication information indicates HARQ feedback, step S708 is executed; otherwise, step S708 is not executed, that is, step S708 is optional.

When step S708 is not performed, the terminal device starts to monitor the PDCCH in order to perform at least one of the following: monitor possible new transmission of downlink data or downlink signaling (ie, new downlink data or downlink signaling). Monitor the scheduling of the RRC release (RRCRelease) message in order to receive the RRC release (RRCRelease) message. When receiving the RRC release (RRCRelease) message, the terminal device switches to the RRC inactive state.

S708: The terminal device performs HARQ feedback according to the reception status of downlink data or downlink signaling.

For this step, refer to step S108, which will not be described again here.

S709. The access network device sends an RRC release (RRCRelease) message to the terminal device to terminate the MT-SDT process.

For this step, refer to step S307, which will not be described again here.

Embodiments of the present application provide a communication method. For the MT-SDT process based on DL CG, the terminal device sends feedback tendency information to the access network device to indicate whether it is inclined to perform HARQ feedback, and the access network device indicates whether the terminal device is Perform HARQ feedback. As shown in Figure 12, the method includes steps S801-S808:

S801. The terminal device sends feedback tendency information to the network device.

For this step, refer to step S701, which will not be described again here.

S802. The access network device obtains feedback indication information.

For this step, refer to step S702, which will not be described again here.

S803. The access network device sends an RRC release (RRCRelease) message to the terminal device in the RRC connected state.

Optionally, the access network device sends feedback indication information to the terminal device. The feedback indication information may be carried in an RRC release (RRCRelease) message, for example, in the DL CG configuration carried in the RRC release (RRCRelease) message.

For other contents of this step, refer to step S401 and will not be described again here.

S804. The core network element sends the downlink data or downlink signaling of the MT-SDT service to the access network device.

S805: The access network device sends a paging message to the terminal device to page the terminal device.

S806. The access network device sends downlink data or downlink signaling of the MT-SDT service to the terminal device on the PDSCH resource indicated by the DL CG configuration.

If the feedback indication information indicates HARQ feedback, step S807 is executed; otherwise, step S807 is not executed, that is, step S807 is optional.

When step S807 is not performed, the terminal device starts to monitor the PDCCH in order to perform at least one of the following: monitor possible new transmission of downlink data or downlink signaling (ie, new downlink data or downlink signaling). Monitor the scheduling of the RRC release (RRCRelease) message in order to receive the RRC release (RRCRelease) message. When receiving the RRC release (RRCRelease) message, the terminal device switches to the RRC inactive state.

S807. The terminal device performs HARQ feedback according to the reception status of downlink data or downlink signaling.

For this step, refer to step S108, which will not be described again here.

S808: The access network device sends an RRC release (RRCRelease) message to the terminal device to terminate the MT-SDT process.

For this step, refer to step S406, which will not be described again here.

To sum up, the embodiment of the present application provides another communication method, which summarizes the communication methods shown in Figures 9 to 12. As shown in Figure 13, the communication method includes S1301-S1306:

S1301. The core network element (for example, the AMF network element, the UPF network element) determines the feedback indication information.

In a possible implementation, the terminal device determines the feedback tendency information according to the reliability requirements of the MT-SDT service being carried out, and sends it to the access network device. The core network element receives the feedback tendency information from the terminal device through the access network device, and determines the feedback indication information based on the feedback tendency information. If the feedback tendency information indicates that the terminal equipment tends not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, then the feedback indication information indicates that the terminal equipment does not perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service. Perform HARQ feedback; or, if the feedback tendency information indicates that the terminal equipment is inclined to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, the feedback indication information indicates that the terminal equipment is inclined to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service. Or downlink signaling for HARQ feedback.

In another possible implementation, the terminal equipment sends the reliability requirements of the MT-SDT service performed by the terminal equipment to the core network element through the access network equipment, and the core network element receives the reliability requirements from the terminal equipment through the access network equipment. The reliability requirements of the MT-SDT service performed by the terminal equipment, and the feedback indication information is determined based on the reliability requirements. If the reliability requirements are low, the feedback indication information instructs the terminal equipment not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service; or, if the reliability requirements are high, the feedback indication information instructs the terminal equipment to perform HARQ feedback for the MT-SDT service. HARQ feedback is performed on the downlink data and/or downlink signaling of the SDT service.

After the core network element determines the feedback indication information, it can send it to the access network device, and then the access network device sends the feedback indication information to the terminal device.

Step S1301 is optional. Please refer to steps S501 and S601 for this step, which will not be described again here.

S1302. The core network element sends the downlink data or downlink signaling of the MT-SDT service to the access network device.

For this step, please refer to steps S503, S603, S704, and S804, which will not be described again here.

S1303. The access network device obtains feedback indication information.

The access network device may obtain the feedback indication information from the core network element, or the access network device may determine the feedback indication information based on the feedback tendency information. For this step, refer to steps S504, S604, S702, and S802, which will not be described again here.

S1304. The access network device sends feedback instruction information to the terminal device.

For this step, refer to steps S505, S507, S509, S605, S607, S703, S705, S707, S803, and S805, which will not be described again here.

It should be noted that at this time, the terminal device may be in the RRC connected state or the RRC inactive state.

S1305. The access network device sends downlink data or downlink signaling of the MT-SDT service to the terminal device in the RRC inactive state.

For this step, please refer to steps S509, S607, S707, and S806, which will not be described again here.

It should be noted that this application does not require the execution order of step S1304 and step S1305, that is, step S1304 may be executed first and then step S1305, or step S1305 may be executed first and then step S1304.

S1306. When the feedback indication information instructs the terminal device to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, the terminal device sends HARQ feedback for the downlink data or downlink signaling to the access network device. Otherwise, no Send HARQ feedback for downlink data or downlink signaling to the access network device.

For this step, refer to steps S108, S509, S607, S707, and S806, which will not be described again here.

It can be understood that in each of the above embodiments, the methods and/or steps implemented by the terminal device can also be implemented by components (such as chips or circuits) of the terminal device. The methods and/or steps implemented by the access network device may also be implemented by components (such as chips or circuits) of the access network device. The methods and/or steps implemented by the core network element can also be implemented by components (such as chips or circuits) of the core network element.

An embodiment of the present application also provides a communication device. The communication device may be the terminal device in the above method embodiment, or a device including the above terminal device, or a chip or functional module in the terminal device. Alternatively, the communication device may be the access network device in the above method embodiment, or a device including the above access network device, or a chip or functional module in the access network device. Alternatively, the communication device may be the core network element in the above method embodiment, or a device including the above core network element, or a chip or functional module within the core network element. Thus realizing the various methods mentioned above.

In order to realize the above functions, the communication device includes hardware structures and/or software modules corresponding to each function. Those skilled in the art can easily realize that the present application can be implemented in the form of hardware or a combination of hardware and computer software with the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein. Whether a certain function is performed by hardware or by computer software driving the hardware depends on the specific application of the technical solution. and design constraints. Skilled artisans may implement the described functionality using different methods for each specific application, but such implementations should not be considered beyond the scope of this application.

Embodiments of the present application can divide the communication device into functional modules according to the above method embodiments. For example, functional modules can be divided into corresponding functional modules, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or software function modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical function division. In actual implementation, there may be other division methods.

Embodiments of the present application also provide a communication device, which may be the terminal equipment, access network equipment or core network element described above. As shown in Figure 14, the communication device 140 includes a processor 1401, a memory 1402 and a transceiver 1403. The processor 1401 is coupled to the memory 1402 and the transceiver 1403. The transceiver 1403 is used to support the communication device to communicate with other communication devices. When the communication device is a terminal device, the processor of the communication device may be the processor 210 shown in Figure 2, the memory of the communication device may be the internal memory 221 shown in Figure 2, and the transceiver of the communication device It may be the mobile communication module 250 and/or the wireless communication module 260 shown in FIG. 2 . When the communication device is an access network device, the processor of the communication device may be the processor 331 shown in Figure 3, and the memory of the communication device may be the memory 332 shown in Figure 3. The transceiver of the communication device The device may be the RF circuit 334 shown in Figure 3. When the communication device is a core network element, the processor of the communication device may be the processor 401 shown in Figure 4, and the memory of the communication device may be the memory 403 shown in Figure 4. The transceiver of the communication device The device may be the communication interface 404 shown in Figure 4. When the processor executes the computer program or instructions in the memory, the methods corresponding to the terminal equipment, access network equipment or core network elements in Figures 5 to 13 are executed.

As shown in Figure 15, an embodiment of the present application also provides a chip system. The chip system 60 includes at least one processor 601 and at least one interface circuit 602 . At least one processor 601 and at least one interface circuit 602 may be interconnected by wires. The processor 601 is used to support the communication device to implement various functions or steps performed by the terminal device or the access network device in the above method embodiments, such as the methods shown in Figures 5 to 13. At least one interface circuit 602 can be used to obtain data from other devices. (such as a memory) receives a signal, or sends a signal to other communication devices (such as a communication interface). The chip system may include chips and may also include other discrete devices.

Embodiments of the present application also provide a computer-readable storage medium. The computer-readable storage medium includes instructions. When the instructions are run on the above-mentioned communication device, the communication device causes the communication device to perform the above-mentioned method embodiment by the terminal device or the access network. Each function or step performed by the device, for example, performs the methods shown in Figures 5-13.

Embodiments of the present application also provide a computer program product including instructions. When the instructions are run on the above-mentioned communication device, the communication device is caused to perform various functions or steps performed by the terminal equipment or the access network equipment in the above-mentioned method embodiments. For example, the methods shown in Figures 5 to 13 are executed.

Regarding the technical effects of communication devices, chip systems, computer-readable storage media, and computer program products, refer to the technical effects of the previous method embodiments.

It should be understood that in the various embodiments of the present application, the size of the sequence numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its functions and internal logic, and should not be used in the embodiments of the present application. The implementation process constitutes any limitation.

Those of ordinary skill in the art can appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented with electronic hardware, or a combination of computer software and electronic hardware. These skills Whether it can be implemented in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each specific application, but such implementations should not be considered beyond the scope of this application.

Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, devices and modules described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be described again here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of modules is only a logical function division. In actual implementation, there may be other division methods. For example, multiple modules or components may be combined or can be integrated into another device, or some features can be ignored, or not implemented. On the other hand, the coupling or direct coupling or communication connection between each other shown or discussed may be through some interfaces, indirect coupling or communication connection of devices or modules, which may be in electrical, mechanical or other forms.

The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located on one device, or they may be distributed to multiple devices. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional module in each embodiment of the present application can be integrated in one device, or each module can exist physically alone, or two or more modules can be integrated in one device.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using a software program, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transferred from a website, computer, server, or data center Transmission to another website, computer, server or data center through wired (such as coaxial cable, optical fiber, Digital Subscriber Line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be accessed by a computer or include one or more data storage devices such as servers and data centers that can be integrated with the medium. The available media may be magnetic media (eg, floppy disk, hard disk, magnetic tape), optical media (eg, DVD), or semiconductor media (eg, Solid State Disk (SSD)), etc.

The above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application. should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

A communication method, characterized in that it is applied to access network equipment, and the method includes:

Send feedback indication information to the terminal device, where the feedback indication information is used to indicate to the terminal device: whether to perform hybrid automatic repeat request HARQ feedback for downlink data and/or downlink signaling of the mobile terminal small data transmission MT-SDT service;

Receive the downlink data or the downlink signaling from the core network element, and send the downlink data or the downlink signaling to the terminal device in the radio resource control RRC inactive state;

Only when the feedback indication information indicates that the terminal device performs HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, receive HARQ for the downlink data or the downlink signaling from the terminal device. feedback.
The method according to claim 1, further comprising:

Receive the feedback indication information from the core network element.
The method according to claim 1, further comprising:

Receive feedback tendency information from the terminal device, where the feedback tendency information is used to indicate whether the terminal device is inclined to perform HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service;

The feedback indication information is determined according to the feedback tendency information, or the feedback tendency information is sent to the core network element, and the feedback tendency information is used by the core network element to determine the feedback indication information.
The method according to claim 3, characterized in that:

If the feedback tendency information indicates that the terminal device prefers not to perform HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service, then the feedback indication information indicates that the terminal device does not perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service. No HARQ feedback is performed on data and/or downlink signaling; or,

If the feedback tendency information indicates that the terminal equipment is inclined to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, then the feedback indication information indicates that the terminal equipment is intended to perform HARQ feedback for the downlink data of the MT-SDT service. and/or downlink signaling for HARQ feedback.
The method according to any one of claims 1 to 4, characterized in that the feedback indication information is carried in a paging message, or in a random access response message, or in scheduling the downlink data. Or in the downlink control information of the downlink signaling, or carried in the RRC release message.
The method according to any one of claims 1 to 5, characterized in that the feedback indication information is associated with a signaling resource bearer that transmits the downlink signaling, or the feedback indication information is associated with a signaling resource bearer that transmits the downlink signaling. The data is associated with the data resource that carries it.
A communication method, characterized in that it is applied to a terminal device, and the method includes:

Receive feedback indication information from the access network device. The feedback indication information is used to indicate to the terminal device whether to perform Hybrid Automatic Repeat Request HARQ for the downlink data and/or downlink signaling of the mobile terminal small data transmission MT-SDT service. feedback;

When in the Radio Resource Control (RRC) inactive state, receive the downlink data or the downlink signaling from the access network device;

Only when the feedback indication information indicates that the terminal device performs HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, the downlink data or the downlink signaling is sent to the access network device. HARQ feedback.
The method according to claim 7, further comprising:

Determine feedback tendency information according to the reliability requirements of the MT-SDT service, and the feedback tendency information is used to indicate whether the terminal device is inclined to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service;

Send feedback tendency information to the access network device, where the feedback tendency information is used to determine the feedback indication information.
The method according to claim 8, characterized in that:

If the feedback tendency information indicates that the terminal device prefers not to perform HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service, then the feedback indication information indicates that the terminal device does not perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service. No HARQ feedback is performed on data and/or downlink signaling; or,

If the feedback tendency information indicates that the terminal equipment is inclined to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, then the feedback indication information indicates that the terminal equipment is intended to perform HARQ feedback for the downlink data of the MT-SDT service. and/or downlink signaling for HARQ feedback.
The method according to claim 7, further comprising:

The access network device sends the reliability requirements of the MT-SDT service performed by the terminal device to the core network element, and the reliability requirements are used by the core network element to determine the feedback indication information.
The method according to claim 10, characterized in that:

If the reliability requirement is low, the feedback indication information instructs the terminal device not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service; or,

If the reliability requirement is high, the feedback indication information instructs the terminal device to perform HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service.
A communication method, characterized in that it is applied to core network elements, and the method includes:

Determine feedback indication information, the feedback indication information is used to instruct the terminal device: whether to perform hybrid automatic repeat request HARQ feedback for downlink data and/or downlink signaling of the mobile terminal small data transmission MT-SDT service;

The access network device sends the feedback indication information to the terminal device, and sends the downlink data or the downlink signaling to the terminal device, so that the terminal device: only when the feedback indication information indicates When the terminal device performs HARQ feedback on the downlink data and/or downlink signaling of the MT-SDT service, it sends HARQ feedback on the downlink data or the downlink signaling to the access network device.
The method according to claim 12, characterized in that the determining feedback indication information includes:

Feedback tendency information from the terminal device is received through the access network device. The feedback tendency information is used to indicate whether the terminal device is inclined to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service. ;

The feedback indication information is determined based on the feedback tendency information.
The method according to claim 13, characterized in that:

If the feedback tendency information indicates that the terminal device prefers not to perform HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service, then the feedback indication information indicates that the terminal device does not perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service. No HARQ feedback is performed on data and/or downlink signaling; or,

If the feedback tendency information indicates that the terminal equipment is inclined to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service, then the feedback indication information indicates that the terminal equipment is inclined to perform HARQ feedback for the MT-SDT service. HARQ feedback is performed on the downlink data and/or downlink signaling of the service.
The method according to claim 12, characterized in that the determining feedback indication information includes:

Receive, through the access network device, the reliability requirements of the MT-SDT service performed by the terminal device from the terminal device;

The feedback indication information is determined according to the reliability requirement.
The method according to claim 15, characterized in that:

If the reliability requirement is low, the feedback indication information instructs the terminal device not to perform HARQ feedback for the downlink data and/or downlink signaling of the MT-SDT service; or,

If the reliability requirement is high, the feedback indication information instructs the terminal device to perform HARQ feedback for downlink data and/or downlink signaling of the MT-SDT service.
The method according to any one of claims 12 to 16, characterized in that the core network element is a user plane functional network element that sends the downlink data, or the core network element is a user plane function that sends the downlink data. Signaling access management function network element.
A communication device, characterized in that it includes a processor and a transceiver. The transceiver is used to communicate with other communication devices. When the processor executes instructions, the method according to any one of claims 1-6 be executed.
A communication device, characterized in that it includes a processor and a transceiver. The transceiver is used to communicate with other communication devices. When the processor executes instructions, the method according to any one of claims 7-11 be executed.
A communication device, characterized in that it includes a processor and a transceiver. The transceiver is used to communicate with other communication devices. When the processor executes instructions, the method according to any one of claims 12-17 be executed.
A computer-readable storage medium, characterized in that it includes instructions that, when the instructions are run on a communication device, cause the communication device to perform the method according to any one of claims 1 to 6, or to perform the following: The method according to any one of claims 7-11, or performing the method according to any one of claims 12-17.
A communication system, characterized by comprising the communication device according to claim 18, the communication device according to claim 19 and the communication device according to claim 20.