WO2024119317A1

WO2024119317A1 - Wireless communication method, and terminal device

Info

Publication number: WO2024119317A1
Application number: PCT/CN2022/136631
Authority: WO
Inventors: 胡奕; 李海涛
Original assignee: Oppo广东移动通信有限公司
Priority date: 2022-12-05
Filing date: 2022-12-05
Publication date: 2024-06-13

Abstract

A wireless communication method, and a terminal device. The method comprises: when a first contention resolution timer during a random access process expires, according to the start time and/or expiration time of the first contention resolution timer, a terminal device determining whether contention resolution fails.

Description

Wireless communication method and terminal device

Technical Field

The embodiments of the present application relate to the field of communications, and specifically to a method and terminal device for wireless communications.

Background technique

In the New Radio (NR) system, a four-step random access process is supported, in which the terminal device starts the contention resolution timer (ra-ContentionResolutionTimer) after sending message 3 (Msg3), and monitors the physical downlink control channel (Physical Downlink Control Channel, PDCCH) to receive message 4 (Msg4) during the running of the ra-ContentionResolutionTimer.

In the Non-Terrestrial Networks (NTN) system, due to the large transmission delay between the terminal device and the network device, in order to avoid invalid PDCCH monitoring caused by starting the ra-ContentionResolutionTimer too early, it is considered to increase the start time of the ra-ContentionResolutionTimer by a delay offset of the round trip time (RTT) between the terminal device and the network device in the NTN system. However, this design will cause the terminal device to be unable to receive the blind retransmission scheduling for the initial transmission of Msg3. However, if the ra-ContentionResolutionTimer is started too early, before the terminal device starts or restarts the ra-ContentionResolutionTimer next time, if the ra-ContentionResolutionTimer times out and does not receive the PDCCH indicating the retransmission of Msg3, the terminal device will think that the contention resolution has failed, affecting the random access efficiency. Therefore, how to perform random access to improve the efficiency of random access is an urgent problem to be solved.

Summary of the invention

The present application provides a wireless communication method and terminal device, which are conducive to improving random access efficiency.

In a first aspect, a wireless communication method is provided, comprising: when a first contention resolution timer in a random access process times out, a terminal device determines whether contention resolution is unsuccessful according to a start time and/or a timeout time of the first contention resolution timer. .

In a second aspect, a wireless communication method is provided, comprising: after successfully receiving a random access response RAR, a terminal device immediately starts a contention resolution timer; and during the running of the contention resolution timer, monitors a physical downlink control channel PDCCH.

In a third aspect, a terminal device is provided for executing the method in the first aspect or its various implementations.

Specifically, the terminal device includes a functional module for executing the method in the above-mentioned first aspect or its various implementation modes.

In a fourth aspect, a terminal device is provided for executing the method in the above-mentioned second aspect or its various implementation modes.

Specifically, the terminal device includes a functional module for executing the method in the above-mentioned second aspect or its various implementation modes.

In a fifth aspect, a terminal device is provided, comprising a processor and a memory, wherein the memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to execute the method in the first aspect or its implementation manners.

In a sixth aspect, a terminal device is provided, comprising a processor and a memory, wherein the memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to execute the method in the second aspect or its implementation manners.

In a seventh aspect, a chip is provided for implementing the method in any one of the first to second aspects or in each of their implementations.

Specifically, the chip includes: a processor, which is used to call and run a computer program from a memory, so that a device equipped with the device executes a method as described in any one of the first to second aspects or their respective implementations.

In an eighth aspect, a computer-readable storage medium is provided for storing a computer program, wherein the computer program enables a computer to execute the method of any one of the first to second aspects or any of their implementations.

In a ninth aspect, a computer program product is provided, comprising computer program instructions, wherein the computer program instructions enable a computer to execute the method in any one of the first to second aspects or any of their implementations.

In a tenth aspect, a computer program is provided, which, when executed on a computer, enables the computer to execute the method in any one of the first to second aspects or in each of their implementations.

Through the above technical solution, when the ra-ContentionResolutionTimer times out, the terminal device can determine whether the contention resolution is unsuccessful based on the start time and/or timeout time of the ra-ContentionResolutionTimer, which is helpful to avoid misjudgment of the contention resolution result, thereby causing the terminal device to retry random access and affecting the efficiency of random access.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1A is a schematic diagram of a communication system architecture provided in an embodiment of the present application.

FIG1B is a schematic diagram of another communication system architecture provided in an embodiment of the present application.

FIG1C is a schematic diagram of another communication system architecture provided in an embodiment of the present application.

FIG2 is a network architecture diagram of NTN based on transparent data satellite.

FIG3 is a network architecture diagram of NTN based on regenerative data satellites.

FIG. 4 is a schematic flow chart of a contention-based four-step random access process.

FIG5 is a schematic diagram of a wireless communication method provided according to an embodiment of the present application.

FIG. 6 is a schematic diagram of a method for determining contention resolution according to an embodiment of the present application.

FIG. 7 is a schematic diagram of another wireless communication method provided according to an embodiment of the present application.

FIG8 is a schematic diagram of a method for starting a contention resolution timer according to an embodiment of the present application.

FIG. 9 is a schematic block diagram of a terminal device provided according to an embodiment of the present application.

FIG10 is a schematic block diagram of another terminal device provided according to an embodiment of the present application.

FIG11 is a schematic block diagram of a communication device provided according to an embodiment of the present application.

FIG. 12 is a schematic block diagram of a chip provided according to an embodiment of the present application.

FIG13 is a schematic block diagram of a communication system provided according to an embodiment of the present application.

Detailed ways

The following will describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. For the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

The technical solutions of the embodiments of the present application can be applied to various communication systems, such as: Global System of Mobile communication (GSM) system, Code Division Multiple Access (CDMA) system, Wideband Code Division Multiple Access (WCDMA) system, General Packet Radio Service (GPRS), Long Term Evolution (LTE) system, Advanced long term evolution (LTE-A) system, New Radio (NR) system, and NR system. Evolved systems, LTE-based access to unlicensed spectrum (LTE-U) systems, NR-based access to unlicensed spectrum (NR-U) systems, non-terrestrial communication networks (NTN) systems, universal mobile telecommunication systems (UMTS), wireless local area networks (WLAN), wireless fidelity (WiFi), fifth-generation communication (5th-Generation, 5G) systems or other communication systems, etc.

Generally speaking, traditional communication systems support a limited number of connections and are easy to implement. However, with the development of communication technology, mobile communication systems will not only support traditional communications, but will also support, for example, device to device (Device to Device, D2D) communication, machine to machine (Machine to Machine, M2M) communication, machine type communication (Machine Type Communication, MTC), vehicle to vehicle (V2V) communication, or vehicle to everything (V2X) communication, etc. The embodiments of the present application can also be applied to these communication systems.

The communication system in the embodiments of the present application can be applied to a carrier aggregation (CA) scenario, a dual connectivity (DC) scenario, or a standalone (SA) networking scenario.

The communication system in the embodiment of the present application can be applied to an unlicensed spectrum, wherein the unlicensed spectrum can also be considered as a shared spectrum; or, the communication system in the embodiment of the present application can also be applied to an authorized spectrum, wherein the authorized spectrum can also be considered as an unshared spectrum.

The embodiments of the present application can be applied to non-terrestrial communication networks (NTN) systems, and can also be applied to terrestrial communication networks (TN) systems.

As an example, the NTN system includes but is not limited to the New Radio NTN (NR-NTN) system and the Internet of Things NTN (IoT-NTN) system. Among them, the IoT-NTN system may include the Narrow Band Internet of Things over NTN (NB-IoT-NTN) system and the enhanced Machine Type Communication over NTN (eMTC-NTN) system.

The embodiments of the present application describe various embodiments in conjunction with network equipment and terminal equipment, wherein the terminal equipment may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication equipment, user agent or user device, etc.

The terminal device can be a station (STATION, ST) in a WLAN, a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA) device, a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal device in the next generation communication system such as the NR network, or a terminal device in the future evolved Public Land Mobile Network (PLMN) network, etc.

In the embodiments of the present application, the terminal device can be deployed on land, including indoors or outdoors, handheld, wearable or vehicle-mounted; it can also be deployed on the water surface (such as ships, etc.); it can also be deployed in the air (for example, on airplanes, balloons and satellites, etc.).

In the embodiments of the present application, the terminal device may be a mobile phone, a tablet computer, a computer with wireless transceiver function, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal device in industrial control, a wireless terminal device in self-driving, a wireless terminal device in remote medical, a wireless terminal device in smart grid, a wireless terminal device in transportation safety, a wireless terminal device in smart city, or a wireless terminal device in smart home, etc. The terminal device involved in the embodiments of the present application may also be referred to as a terminal, a user equipment (UE), an access terminal device, a vehicle-mounted terminal, an industrial control terminal, a UE unit, a UE station, a mobile station, a mobile station, a remote station, a remote terminal device, a mobile device, a UE terminal device, a wireless communication device, a UE agent, or a UE device, etc. The terminal device may also be fixed or mobile.

As an example but not limitation, in the embodiments of the present application, the terminal device may also be a wearable device. Wearable devices may also be referred to as wearable smart devices, which are a general term for wearable devices that are intelligently designed and developed using wearable technology for daily wear, such as glasses, gloves, watches, clothing, and shoes. A wearable device is a portable device that is worn directly on the body or integrated into the user's clothes or accessories. Wearable devices are not only hardware devices, but also powerful functions achieved through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include full-featured, large-sized, and fully or partially independent of smartphones, such as smart watches or smart glasses, as well as devices that only focus on a certain type of application function and need to be used in conjunction with other devices such as smartphones, such as various types of smart bracelets and smart jewelry for vital sign monitoring.

In an embodiment of the present application, the network device may be a device for communicating with a mobile device. The network device may be an access point (AP) in WLAN, a base station (BTS) in GSM or CDMA, a base station (NodeB, NB) in WCDMA, an evolved base station (Evolutional Node B, eNB or eNodeB) in LTE, or a relay station or access point, or a vehicle-mounted device, a wearable device, and a network device (gNB) in an NR network, or a network device in a future evolved PLMN network, or a network device in an NTN network, etc.

As an example and not limitation, in an embodiment of the present application, the network device may have a mobile feature, for example, the network device may be a mobile device. In some embodiments of the present application, the network device may be a satellite or a balloon station. For example, the satellite may be a low earth orbit (LEO) satellite, a medium earth orbit (MEO) satellite, a geostationary earth orbit (GEO) satellite, a high elliptical orbit (HEO) satellite, etc. In some embodiments of the present application, the network device may also be a base station set up in a location such as land or water.

In an embodiment of the present application, a network device can provide services for a cell, and a terminal device communicates with the network device through transmission resources used by the cell (for example, frequency domain resources, or spectrum resources). The cell can be a cell corresponding to a network device (for example, a base station), and the cell can belong to a macro base station or a base station corresponding to a small cell. The small cells here may include: metro cells, micro cells, pico cells, femto cells, etc. These small cells have the characteristics of small coverage and low transmission power, and are suitable for providing high-speed data transmission services.

Exemplarily, FIG1A is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application. As shown in FIG1A, the communication system 100 may include a network device 110, and the network device 110 may be a device that communicates with a terminal device 120 (or referred to as a communication terminal, terminal). The network device 110 may provide communication coverage for a specific geographical area, and may communicate with terminal devices located in the coverage area.

FIG1A exemplarily shows a network device and two terminal devices. In some embodiments of the present application, the communication system 100 may include multiple network devices and each network device may include other number of terminal devices within its coverage area, which is not limited in the embodiments of the present application.

Exemplarily, FIG1B is a schematic diagram of the architecture of another communication system provided in an embodiment of the present application. Please refer to FIG1B, which includes a terminal device 1101 and a satellite 1102, and wireless communication can be performed between the terminal device 1101 and the satellite 1102. The network formed between the terminal device 1101 and the satellite 1102 can also be referred to as NTN. In the architecture of the communication system shown in FIG1B, the satellite 1102 can have the function of a base station, and the terminal device 1101 and the satellite 1102 can communicate directly. Under the system architecture, the satellite 1102 can be referred to as a network device. In some embodiments of the present application, a plurality of network devices 1102 may be included in the communication system, and each network device 1102 may include other number of terminal devices within its coverage range, which is not limited in the embodiments of the present application.

Exemplarily, FIG1C is a schematic diagram of the architecture of another communication system provided in an embodiment of the present application. Referring to FIG1C, it includes a terminal device 1201, a satellite 1202, and a base station 1203. Wireless communication can be performed between the terminal device 1201 and the satellite 1202, and communication can be performed between the satellite 1202 and the base station 1203. The network formed between the terminal device 1201, the satellite 1202, and the base station 1203 can also be referred to as NTN. In the architecture of the communication system shown in FIG1C, the satellite 1202 may not have the function of a base station, and the communication between the terminal device 1201 and the base station 1203 needs to be transferred through the satellite 1202. In this system architecture, the base station 1203 can be referred to as a network device. In some embodiments of the present application, a plurality of network devices 1203 may be included in the communication system, and other number of terminal devices may be included within the coverage range of each network device 1203, which is not limited in the embodiment of the present application.

It should be noted that Figures 1A-1C are only examples of the system to which the present application is applicable. Of course, the method shown in the embodiment of the present application can also be applied to other systems, such as 5G communication systems, LTE communication systems, etc. The embodiment of the present application does not make specific limitations on this.

In some embodiments of the present application, the wireless communication system shown in Figures 1A-1C may also include other network entities such as a mobility management entity (Mobility Management Entity, MME), an access and mobility management function (Access and Mobility Management Function, AMF), etc., but the embodiments of the present application are not limited to this.

It should be understood that the device with communication function in the network/system in the embodiment of the present application can be referred to as a communication device. Taking the communication system 100 shown in FIG. 1A as an example, the communication device may include a network device 110 and a terminal device 120 with communication function, and the network device 110 and the terminal device 120 may be the specific devices described above, which will not be repeated here; the communication device may also include other devices in the communication system 100, such as other network entities such as a network controller and a mobile management entity, which is not limited in the embodiment of the present application.

It should be understood that the terms "system" and "network" are often used interchangeably in this article. The term "and/or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and/or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character "/" in this article generally indicates that the associated objects before and after are in an "or" relationship.

It should be understood that the "indication" mentioned in the embodiments of the present application can be a direct indication, an indirect indication, or an indication of an association relationship. For example, A indicates B, which can mean that A directly indicates B, for example, B can be obtained through A; it can also mean that A indirectly indicates B, for example, A indicates C, and B can be obtained through C; it can also mean that there is an association relationship between A and B.

In the description of the embodiments of the present application, the term "corresponding" may indicate a direct or indirect correspondence between two items, or an association relationship between the two items, or a relationship between indication and being indicated, configuration and being configured, and the like.

In some embodiments of the present application, "predefined" may be implemented by pre-saving corresponding codes, tables or other methods that can be used to indicate relevant information in a device (for example, including a terminal device and a network device), and the present application does not limit the specific implementation method thereof. For example, predefined may refer to those defined in the protocol.

In some embodiments of the present application, the "protocol" may refer to a standard protocol in the communication field, for example, it may include an LTE protocol, an NR protocol, and related protocols used in future communication systems, and the present application does not limit this.

The main application scenarios of NR include: Enhance Mobile Broadband (eMBB), Ultra-Reliable and Low Latency Communication (URLLC), and massive machine type of communication (mMTC).

In the embodiment of the present application, NR can also be deployed independently. In order to reduce air interface signaling and quickly restore wireless connection and data service in 5G network environment, a new radio resource control (RRC) state is defined, namely RRC_INACTIVE (inactive) state. This state is different from RRC_IDLE (idle) and RRC_CONNECTED (connected) states.

In the RRC_IDLE state: mobility is based on the cell selection reselection of the terminal device, paging is initiated by the core network (CN), and the paging area is configured by the CN. There is no terminal device access stratum (AS) context on the base station side, and there is no RRC connection.

In the RRC_CONNECTED state: an RRC connection exists, and a terminal device AS context exists between the base station and the terminal device. The network device knows the location of the terminal device at the specific cell level. Mobility is mobility controlled by the network device. Unicast data can be transmitted between the terminal device and the base station.

RRC_INACTIVE: The mobility is the cell selection reselection based on the terminal device. There is a connection between CN and NR. The AS context of the terminal device exists on a certain base station. The paging is triggered by the Radio Access Network (RAN). The RAN-based paging area is managed by the RAN. The network equipment knows the location of the terminal device based on the RAN paging area level.

In some scenarios, the non-terrestrial network (NTN) technology has begun to be studied. NTN generally uses satellite communication to provide communication services to ground users. Compared with ground cellular network communication, satellite communication has many unique advantages. First, satellite communication is not limited by the user's geographical location. For example, general land communication cannot cover areas such as oceans, mountains, deserts, etc. where communication equipment cannot be set up or where communication coverage is not provided due to sparse population. For satellite communication, since one satellite can cover a large area of land, and satellites can orbit the earth, in theory every corner of the earth can be covered by satellite communication. Secondly, satellite communication has great social value. Satellite communication can be covered at a low cost in remote mountainous areas, poor and backward countries or regions, so that people in these areas can enjoy advanced voice communication and mobile Internet technology, which is conducive to narrowing the digital divide with developed areas and promoting the development of these areas. Thirdly, satellite communication has a long distance, and the cost of communication does not increase significantly as the communication distance increases; finally, satellite communication has high stability and is not restricted by natural disasters.

Communication satellites are divided into LEO satellites, MEO satellites, GEO satellites, HEO satellites, etc. according to the different orbital altitudes. Currently, the main research is on LEO and GEO.

The altitude range of LEO is 500km~1500km, and the corresponding orbital period is about 1.5 hours~2 hours. The signal propagation delay of single-hop communication between users is generally less than 20ms. The maximum satellite visibility time is 20 minutes. The signal propagation distance is short, the link loss is small, and the transmission power requirement of the user terminal is not high.

The GEO orbit altitude is 35786km, and its rotation period around the earth is 24 hours. The signal propagation delay of single-hop communication between users is generally 250ms.

In order to ensure satellite coverage and improve the system capacity of the entire satellite communication system, satellites use multiple beams to cover the ground. A satellite can form dozens or even hundreds of beams to cover the ground; a satellite beam can cover a ground area with a diameter of tens to hundreds of kilometers.

FIG. 2 and FIG. 3 show two NTN network architectures, wherein FIG. 2 is an NTN network architecture based on transparent forwarding, and FIG. 3 is an NTN network architecture based on regenerative forwarding.

Among them, the NTN network may include the following network elements: one or more gateways, which are used to connect satellites and ground public networks. For NTN networks based on transparent forwarding, the gateway and the satellite communicate through a feeder link, and the satellite and the terminal can communicate through a service link. For NTN networks based on regenerative forwarding, satellites communicate with each other through an interstar link, the gateway and the satellite communicate through a feeder link, and the satellite and the terminal can communicate through a service link.

In transparent forwarding, the satellite only provides the functions of wireless frequency filtering, frequency conversion and amplification. It only provides transparent forwarding of signals and does not change the waveform signal it forwards.

In regeneration and forwarding, the satellite can provide demodulation/decoding, routing/conversion, encoding/modulation functions in addition to the functions of wireless frequency filtering, frequency conversion and amplification. It has some or all functions of a base station.

In the NR system, the random access process is mainly triggered by the following events:

The UE establishes a wireless connection when it initially accesses: the UE changes from the RRC_IDLE state to the RRC_CONNECTED state;

Radio Resource Control (RRC) connection reestablishment process: to enable the UE to reestablish the wireless connection after a radio link failure;

Handover: UE needs to establish uplink synchronization with the new cell;

In the RRC_CONNECTED state, downlink data arrives, and the uplink is out of sync at this time;

In the RRC_CONNECTED state, uplink data arrives, and the uplink is out of sync or there is no PUCCH resource for sending SR

Scheduling Request (SR) failed;

Synchronous reconfiguration request from RRC;

The UE transitions from the RRC_INACTIVE state to the RRC_CONNECTED state;

Establishing time alignment during the SCell addition process;

Request additional system information (System Information, SI);

Beam failure recovery.

In the NR system, a four-step random access process is supported, specifically including the sending process of message 1 (Msg1)-message 4 (Msg4). As an example, as shown in Figure 4, the four-step random access process includes the following steps:

Step 1: The terminal device sends a random access preamble (Preamble, also known as Msg 1) to the network device.

Among them, the random access preamble code may also be called a preamble code, a random access preamble code sequence, a preamble code sequence, etc.

Specifically, the terminal device can select a physical random access channel (PRACH) resource and send the selected preamble on the selected PRACH.

Based on the Preamble, the network device can estimate the uplink timing and the grant size required for the terminal device to transmit Msg3.

Step 2: The network device sends a random access response (Random Access Response, RAR, also known as Msg 2) to the terminal device.

After the terminal device sends the Preamble to the network device, it can open a random access response window (ra-ResponseWindow) and listen to the physical downlink control channel (PDCCH) encrypted with the random access radio network temporary identifier (RA-RNTI) in the ra-ResponseWindow. Among them, RA-RNTI is calculated based on the time-frequency position of the PRACH that sends the Preamble. Therefore, if multiple terminal devices send Preamble on the same RO, the corresponding RARs are multiplexed in the same RAR Media Access Control Protocol Data Unit (MAC PDU). If the terminal successfully receives the RA-RNTI-encrypted PDCCH corresponding to the RO resource that sent the Preamble, including the RAR, the RAR may include the following information:

The RAR subheader contains BI, which is used to indicate the backoff time for retransmitting Msg1;

RAPID in RAR: The network device responds to the received Preamble index;

The RAR payload contains the Timing Advance Group (TAG), which is used to adjust the uplink timing.

Uplink grant (UL grant): used to schedule uplink resource indication of Msg3;

Temporary Cell RNTI (TC-RNTI): used to scramble the PDCCH of Msg4 (initial access).

If the terminal receives a PDCCH scrambled by RAR-RNTI, and the RAR contains the Preamble index sent by itself, the terminal device considers that the random access response has been successfully received.

Step 3, the terminal device sends Msg 3.

Msg 3 is mainly used to notify the network device of the trigger event of the random access. For different random access trigger events, the Msg 3 sent by the terminal device in step 3 may include different contents.

For example, for the RRC connection reestablishment scenario, Msg 3 may include the establishment cause and UE identity.

After sending Msg3, the terminal starts a contention resolution timer (ra-ContentionResolutionTimer), and monitors the PDCCH to receive Msg4 during the running period of the ra-ContentionResolutionTimer.

Step 4: The network device sends a contention resolution message (Msg 4) to the terminal device.

Msg4 has two functions: one is used for contention conflict resolution, and the second is for the network device to transmit the RRC configuration message to the terminal device. There are two ways to resolve contention conflicts:

Method 1: If the terminal device carries C-RNTI in Msg3, Msg4 is scheduled with PDCCH scrambled with C-RNTI.

Method 2: If the terminal device does not carry C-RNTI in Msg3, such as initial access, Msg4 is scheduled with PDCCH scrambled with TC-RNTI. At this time, the conflict is resolved by the UE receiving the PDSCH of Msg4, obtaining the conflict resolution ID, and then matching the conflict resolution ID with the common control channel (CCCH) service data unit (SDU) in Msg 3 to determine whether the conflict is resolved.

From the above random access process, it can be seen that the main purpose of random access is to achieve uplink synchronization between the terminal device and the cell. During the random access process, the network device can know the time when the terminal device sends the Preamble based on the RACH time-frequency resources used by the Preamble received from the terminal device, and thus determine the initial TA of the terminal device based on the sending and receiving time of the Preamble, and inform the terminal device through the RAR.

In the TN system, the terminal device starts the ra-ContentionResolutionTimer immediately after each Msg3 transmission (including initial transmission and retransmission) is completed, and the terminal device monitors the PDCCH during the operation of the ra-ContentionResolutionTimer. The terminal device needs to wait at least one round trip time (RTT) from sending Msg3 to receiving Msg4. Since the signal transmission delay between the network device and the terminal device in the NTN system is much greater than the signal transmission delay between the network device and the terminal device in the TN system, for example, for the GEO scenario, the RTT can be up to 541.46ms. In order to avoid invalid PDCCH monitoring caused by the terminal device starting the ra-ContentionResolutionTimer too early, it is considered to increase the start time of the ra-ContentionResolutionTimer in the NTN system by a delay offset of UE-gNB RTT on the basis of the TN system. However, this design will cause the terminal device to be unable to receive the blind retransmission scheduling for the initial transmission of Msg3.

In order to enable the terminal to monitor the blind scheduling retransmission grant for the initial transmission of Msg3, consider that the terminal starts the ra-ContentionResolutionTimer immediately after completing the initial transmission of Msg3. Since the next time the terminal device starts or restarts the ra-ContentionResolutionTimer is the time when the terminal device completes the initial transmission of Msg3 plus one UE-gNB RTT, it is possible that the original running ra-ContentionResolutionTimer has timed out before the terminal device starts/restarts the ra-ContentionResolutionTimer next time. If the PDCCH indicating the retransmission of Msg3 scrambled by TC-RNTI is not received after the ra-ContentionResolutionTimer is started, the terminal device will consider that the contention resolution has failed, and the terminal device needs to retry random access. After sending the initial transmission of Msg3 and experiencing a UE-gNB RTT delay, the terminal device needs to continue to monitor the scheduling of Msg4, and should not consider that the contention resolution has failed in advance, which affects the random access efficiency. Therefore, how to perform random access to improve the random access efficiency is an urgent problem to be solved.

To facilitate understanding of the technical solutions of the embodiments of the present application, the technical solutions of the present application are described in detail below through specific embodiments. The above related technologies can be arbitrarily combined with the technical solutions of the embodiments of the present application as optional solutions, and they all belong to the protection scope of the embodiments of the present application. The embodiments of the present application include at least part of the following contents.

FIG. 5 is a schematic flow chart of a wireless communication method 200 according to an embodiment of the present application. As shown in FIG. 5 , the method 200 includes the following contents:

S210, when the first contention resolution timer (i.e., ra-ContentionResolutionTimer) in the random access process times out, the terminal device determines whether the contention resolution is unsuccessful, or in other words, whether the contention resolution fails, based on the start time and/or timeout time of the first contention resolution timer.

Therefore, in an embodiment of the present application, when the contention resolution timer times out, it is not directly determined that the contention resolution is unsuccessful, but rather it is determined whether the contention resolution is unsuccessful in combination with the start time and/or timeout time of the contention resolution timer. This helps to avoid the problem that before the next start or restart of the contention resolution timer, the last started contention resolution timer has timed out, resulting in a misjudgment of the contention resolution result, so that the terminal device needs to retry random access, affecting the efficiency of random access.

In some embodiments, the cell that the terminal device initiates the random access procedure and wants to access is an NTN cell, or the terminal device is a terminal device in the NTN cell.

In some embodiments, the first contention resolution timer is the contention resolution timer that was most recently started or restarted by the terminal device.

In some embodiments, the start time of the first contention resolution timer refers to the time unit for starting the first contention resolution timer, such as the symbol or time slot for starting the first contention resolution timer, or the absolute time for starting the first contention resolution timer. Similarly, the timeout time of the first contention resolution timer refers to the time unit when the first contention resolution timer times out, such as the symbol or time slot when the first contention resolution timer times out, or the absolute time when the first contention resolution timer times out.

In some embodiments, the start condition of ra-ContentionResolutionTimer may include at least one of the following:

Start condition 1: During the random access process, the terminal device starts the ra-ContentionResolutionTimer immediately after successfully receiving the RAR. Starting the ra-ContentionResolutionTimer based on this condition is conducive to avoiding missing the blind retransmission scheduling for the initial transmission of Msg3, or in other words, it is conducive to the terminal device receiving the blind retransmission scheduling for the initial transmission of Msg3.

For example, the terminal device starts ra-ContentionResolutionTimer at the Mth PDCCH monitoring opportunity after successfully receiving the RAR, where M is a positive integer.

For another example, the terminal device starts ra-ContentionResolutionTimer in the Nth time unit after successfully receiving the RAR, where N is a positive integer.

Optionally, the M is predefined or configured by the network device.

Optionally, N is predefined or configured by the network device.

Optionally, the Nth time unit may be the Nth symbol, the Nth time slot, etc., which is not limited in the present application.

Start condition 2: During the random access process, the terminal device starts the ra-ContentionResolutionTimer immediately after sending the initial transmission of Msg3. Starting the ra-ContentionResolutionTimer based on this condition is conducive to avoiding missing the blind retransmission scheduling for the initial transmission of Msg3, or in other words, it is conducive to the terminal receiving the blind retransmission scheduling for the initial transmission of Msg3.

For example, when the initial transmission of Msg3 does not use repeated transmission, the terminal device immediately starts the ra-ContentionResolutionTimer after sending the first symbol after the initial transmission of Msg3.

For another example, when the initial transmission of Msg3 uses repeated transmission, the terminal device immediately starts the ra-ContentionResolutionTimer at the first symbol after sending all repeated transmissions of Msg3.

Start condition 3: During the random access process, the terminal device starts the ra-ContentionResolutionTimer in the first time unit of the random access process. The first time unit is the time unit after the terminal device sends the initial transmission of message 3 and experiences a first duration, and the first duration is equal to the RTT between the terminal device and the network device.

For example, when the initial transmission of Msg3 does not use repeated transmission, the terminal device starts ra-ContentionResolutionTimer after sending the initial transmission of Msg3 and the first time duration has elapsed.

For another example, when repeated transmission is used for the initial transmission of Msg3, the terminal device starts the ra-ContentionResolutionTimer after sending all repeated transmissions of Msg3 and the first time duration has elapsed.

In some embodiments, the network device may refer to a network device in the NTN system, such as a ground base station, specifically a gNB, and the first duration may be UE-gNB RTT.

In some embodiments, the terminal device may monitor the PDCCH during the running of the ra-ContentionResolutionTimer, for example, monitor the PDCCH indicating the retransmission of Msg3 encrypted by TC-RNTI.

In some embodiments, when the contention resolution timer times out, whether the contention resolution is unsuccessful should be determined based on whether a PDCCH indicating the retransmission of Msg3 with TC-RNTI scrambling is received after the contention resolution timer started in the first time unit is started. Otherwise, it will lead to a misjudgment of the contention resolution, which will cause the terminal device to retry random access, affecting the efficiency of random access.

Therefore, in some embodiments, the S210 includes:

When the first contention resolution timer times out, the terminal device determines whether contention resolution is unsuccessful based on whether the start time of the first contention resolution timer is the time when the RAR is successfully received, or the time when the initial transmission of Msg3 is completed, or whether it is earlier than the first time unit; or

When the first contention resolution timer times out and no PDCCH indicating retransmission of Msg3 encrypted by TC-RNTI is received after the first contention resolution timer is started, the terminal device determines whether the contention resolution is unsuccessful based on whether the start time of the first contention resolution timer is the time when the RAR is successfully received, or whether it is the time when the initial transmission of Msg3 is sent, or whether it is earlier than the first time unit; or

When the first contention resolution timer times out, the terminal device determines whether contention resolution is unsuccessful according to whether the timeout time of the first contention resolution timer is earlier than the first time unit; or

When the first contention resolution timer times out and no PDCCH indicating retransmission of Msg3 encrypted with TC-RNTI is received after the first contention resolution timer is started, the terminal device determines whether the contention resolution is unsuccessful based on whether the timeout time of the first contention resolution timer is earlier than the first time unit.

In some embodiments, the terminal device determines whether contention resolution is unsuccessful according to the start time and/or timeout time of the first contention resolution timer, including:

When the first condition is met, the terminal device does not consider that the contention resolution is unsuccessful, wherein the first condition includes one of the following:

The first contention resolution timer is a contention resolution timer started for the first time in the random access process;

The first contention resolution timer is started before the first time unit in the random access process, wherein the first time unit is a time unit after the terminal device sends the initial transmission of message 3 and experiences a first duration, and the first duration is equal to the round-trip delay RTT between the terminal device and the network device;

The first contention resolution timer times out before a first time unit in the random access process, wherein the first time unit is a time unit after the terminal device sends the initial transmission of message 3 and experiences a first duration, and the first duration is equal to the RTT between the terminal device and the network device;

The first contention resolution timer is started immediately after the terminal device successfully receives the random access response RAR;

The first contention resolution timer is started immediately after the terminal device completes the initial transmission of message 3.

In some embodiments, the contention resolution timer started for the first time in the random access process may be started under the aforementioned start condition 1, or started under the aforementioned start condition 2.

In some embodiments, the first contention resolution timer is started immediately after the terminal device successfully receives the random access response RAR (corresponding to the aforementioned start condition 1), and may include:

The terminal device starts the first contention resolution timer at the Mth PDCCH monitoring opportunity after successfully receiving the RAR; or

The terminal device starts the first contention resolution timer in the Nth time unit after successfully receiving the RAR.

The specific implementation of M, M, and time units refers to the relevant description in the aforementioned start condition 1, which will not be repeated here for the sake of brevity.

In some embodiments, the first contention resolution timer is started immediately after the terminal device sends the initial transmission of message 3 (corresponding to the aforementioned start condition 2), and may include:

If the initial transmission of Msg3 does not use repeated transmission, the first contention resolution timer is started at the first symbol after the terminal device sends the initial transmission of Msg3; or

If the initial transmission of Msg3 uses repeated transmission, the first contention resolution timer is started at the first symbol after the terminal device sends all repeated transmissions of the initial transmission of Msg3.

In some embodiments, the first condition further includes:

After the first contention resolution timer is started, the terminal device does not receive the PDCCH indicating the retransmission of Msg3 encrypted by TC-RNTI.

In some embodiments, the first condition further includes:

The terminal device has the capability of monitoring the blind retransmission scheduling of the initial transmission of message 3; and/or,

The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.

That is, the first condition may include one of the following conditions:

The first contention resolution timer is a contention resolution timer started for the first time in the random access process, and after the first contention resolution timer is started, the terminal device does not receive a PDCCH indicating retransmission of Msg3 scrambled by TC-RNTI;

The first contention resolution timer is started before the first time unit in the random access process, and after the first contention resolution timer is started, the terminal device does not receive a PDCCH indicating retransmission of Msg3 scrambled by TC-RNTI;

The first contention resolution timer times out before the first time unit in the random access process, and after the first contention resolution timer is started, the terminal device does not receive a PDCCH indicating retransmission of Msg3 scrambled by TC-RNTI;

The first contention resolution timer is started immediately after the terminal device successfully receives the random access response RAR, and after the first contention resolution timer is started, the terminal device does not receive the PDCCH indicating the retransmission of Msg3 scrambled by TC-RNTI;

The first contention resolution timer is started immediately after the terminal device sends the initial transmission of message 3, and after the first contention resolution timer is started, the terminal device does not receive the PDCCH indicating the retransmission of Msg3 encrypted by TC-RNTI.

In some other embodiments, the first condition may include one of the following conditions:

For a terminal device having a blind retransmission scheduling capability of monitoring the initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring the initial transmission of Msg3, the first contention resolution timer is a contention resolution timer started for the first time in the random access process;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, the first contention resolution timer is started before the first time unit in the random access process;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, the first contention resolution timer times out before a first time unit in the random access process;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, the first contention resolution timer is started immediately after the terminal device successfully receives the RAR;

For a terminal device having the capability of monitoring blind retransmission scheduling of initial transmission of Msg3 and/or having the requirement of monitoring blind retransmission scheduling of initial transmission of Msg3, the first contention resolution timer is started immediately after the terminal device sends the initial transmission of Msg3.

In some further embodiments, the first condition may include one of the following conditions:

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, the first contention resolution timer is a contention resolution timer started for the first time in the random access process, and after the first contention resolution timer is started, the terminal device does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, the first contention resolution timer is started before the first time unit in the random access process, and after the first contention resolution timer is started, the terminal device does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, the first contention resolution timer is timed out before the first time unit in the random access process, and after the first contention resolution timer is started, the terminal device does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, the first contention resolution timer is started immediately after the terminal device successfully receives the RAR, and after the first contention resolution timer is started, the terminal device does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3;

For a terminal device having the capability of monitoring blind retransmission scheduling of initial transmission of Msg3 and/or having the need of monitoring blind retransmission scheduling of initial transmission of Msg3, the first contention resolution timer is started immediately after the terminal device sends the initial transmission of Msg3, and after the first contention resolution timer is started, the terminal device does not receive the TC-RNTI encrypted PDCCH indicating the retransmission of Msg3.

When the second condition is met, the terminal device considers that the contention resolution is unsuccessful, wherein the second condition includes one of the following:

After the first contention resolution timer is started, the terminal device does not receive the PDCCH indicating the retransmission of Msg3 scrambled by TC-RNTI, and the first contention resolution timer is not started at the moment when the terminal device successfully receives the RAR;

After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of Msg3 encrypted by TC-RNTI, and the first contention resolution timer is not started at the moment when the terminal device completes the initial transmission of Msg3;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH indicating the retransmission of Msg3 encrypted by TC-RNTI, and the time of starting the first contention resolution timer is no earlier than the first time unit in the random access process, wherein the first time unit is the time unit after the terminal device sends the initial transmission of Msg3 and experiences a first duration, and the first duration is equal to the RTT between the terminal device and the network device;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH indicating the retransmission of Msg3 encrypted by TC-RNTI, and the time when the first contention resolution timer times out is no earlier than the first time unit in the random access process, wherein the first time unit is the time unit when the terminal device sends the initial transmission of Msg3 and experiences the first duration, and the first duration is equal to the RTT between the terminal device and the network device;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH indicating the retransmission of Msg3 scrambled by TC-RNTI, and the first contention resolution timer is not the contention resolution timer started for the first time in the random access process;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH indicating the retransmission of Msg3 scrambled by TC-RNTI, and the terminal device starts the contention resolution timer at the moment of successfully receiving the RAR, and the first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of receiving the RAR;

After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of Msg3 encrypted by TC-RNTI, and the terminal device starts the contention resolution timer at the moment of sending the initial transmission of Msg3. The first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of sending the initial transmission of Msg3.

In some embodiments, the first contention resolution timer is not started at the moment when the terminal device successfully receives the RAR, which may mean that the first contention resolution timer is not started under start condition 1.

For example, the first contention resolution timer is not started at the Mth PDCCH monitoring opportunity after the terminal device successfully receives the RAR.

For another example, the first contention resolution timer is not started at the Nth time unit after the terminal device successfully receives the RAR.

In some embodiments, the first contention resolution timer is not started after the terminal device sends the initial transmission of Msg3, which may mean that the first contention resolution timer is not started under start condition 2.

For example, if the initial transmission of Msg3 does not use repeated transmission, the first contention resolution timer is not started at the first symbol after the terminal device sends the initial transmission of Msg3.

For another example, if the initial transmission of Msg3 uses repeated transmission, the first contention resolution timer is not started at the first symbol after the terminal device sends all repeated transmissions of the initial transmission of Msg3.

In some embodiments, the terminal device starts the contention resolution timer at the moment of successfully receiving the RAR, which may mean that the terminal device starts the contention resolution timer under the aforementioned start condition 1. The specific start method refers to the relevant description in the previous text and will not be repeated here.

In some embodiments, the terminal device starts the contention resolution timer at the moment of sending the initial transmission of Msg3, which means that the terminal device starts the contention resolution timer under the aforementioned start condition 2. The specific start method refers to the relevant description in the previous text and will not be repeated here.

In some embodiments, the second condition further includes:

That is, the second condition may include one of the following conditions:

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, after the first contention resolution timer is started, the terminal device does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3, and the first contention resolution timer is not started at the moment when the terminal device successfully receives a RAR;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, after the first contention resolution timer is started, the terminal device has not received a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3, and the first contention resolution timer is not started at the moment when the terminal device completes sending an initial transmission of Msg3;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, after the first contention resolution timer is started, the terminal device does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3, and the time for starting the first contention resolution timer is no earlier than the first time unit in the random access process;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, after the first contention resolution timer is started, the terminal device does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3, and the time when the first contention resolution timer times out is no earlier than the first time unit in the random access process;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, after the first contention resolution timer is started, the terminal device does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3, and the first contention resolution timer is not a contention resolution timer started for the first time in a random access process;

For a terminal device having a blind retransmission scheduling capability of monitoring an initial transmission of Msg3 and/or having a blind retransmission scheduling requirement of monitoring an initial transmission of Msg3, after the first contention resolution timer is started, the terminal device does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3, and the terminal device starts the contention resolution timer at the moment of successfully receiving the RAR, and the first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of receiving the RAR;

For a terminal device having the capability of monitoring blind retransmission scheduling of initial transmission of Msg3 and/or having the need of monitoring blind retransmission scheduling of initial transmission of Msg3, after the first contention resolution timer is started, the terminal device has not received the TC-RNTI-scrambled PDCCH indicating retransmission of Msg3, and the terminal device starts the contention resolution timer at the moment of sending the initial transmission of Msg3. The first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of sending the initial transmission of Msg3.

In some embodiments, if the second condition is met, the terminal device discards the TC-RNTI.

In conjunction with the example shown in FIG6 , the terminal device starts the ra-ContentionResolutionTimer immediately after sending the initial transmission of Msg3. Specifically, the ra-ContentionResolutionTimer is started at time t1, and the time after UE-gNBRTT from t1 is time t3. The ra-ContentionResolutionTimer times out at time t2, where t2 is earlier than t3, that is, before the next start or restart of the ra-ContentionResolutionTimer, the last started ra-ContentionResolutionTimer has timed out. Since the start time or timeout time of the ra-ContentionResolutionTimer is before time t3, the terminal device does not consider that the contention resolution has failed. Further, at time t3, the terminal device starts or restarts the ra-ContentionResolutionTimer. During the operation of the ra-ContentionResolutionTimer, the terminal device monitors the PDCCH indicating the retransmission of Msg3 encrypted by TC-RNTI, and determines whether the contention resolution is unsuccessful based on the reception of the PDCCH.

In summary, when the ra-ContentionResolutionTimer times out, the terminal device can determine whether the contention resolution is unsuccessful, or in other words, whether the contention resolution fails, according to the start time and/or timeout time of the ra-ContentionResolutionTimer.

In some implementations, when the first condition is met, the terminal device does not consider the contention resolution to be unsuccessful.

Optionally, the first condition may include that the start time of the ra-ContentionResolutionTimer is earlier than the time unit corresponding to the terminal device sending the initial transmission of Msg3 plus the UE-gNB RTT.

In some other implementations, when the second condition is met, the terminal device considers that the contention resolution is unsuccessful.

Optionally, the second condition may include that the start time of the ra-ContentionResolutionTimer is no earlier than the time unit corresponding to the terminal device sending the initial transmission of Msg3 plus the UE-gNB RTT.

FIG. 7 is a schematic flow chart of a wireless communication method 300 according to another embodiment of the present application. As shown in FIG. 7 , the method 300 includes the following contents:

S310, after successfully receiving the random access response RAR, the terminal device immediately starts a contention resolution timer;

S320: Monitor a physical downlink control channel PDCCH during the running of the contention resolution timer.

For example, monitoring the TC-RNTI-scrambled PDCCH indicating the retransmission of Msg3 is helpful to avoid missing the monitoring of the PDCCH indicating the blind retransmission scheduling of Msg3.

In some embodiments, the terminal device starts a contention resolution timer at the Mth PDCCH monitoring opportunity after successfully receiving the RAR, where M is a positive integer.

In some embodiments, the terminal device starts a contention resolution timer at the Nth time unit after successfully receiving the RAR, where N is a positive integer.

Optionally, the M is predefined or configured by the network device.

Optionally, N is predefined or configured by the network device.

In some embodiments, the terminal device initiates random access to a first cell, and the first cell supports blind retransmission scheduling of initial transmission of Msg3.

In some embodiments, the terminal device has the ability to monitor the blind retransmission scheduling of the initial transmission of Msg3; and/or,

The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of Msg3.

For example, when the cell that the terminal device wants to access supports blind retransmission scheduling of Msg3 initial transmission, and the terminal device has the ability to monitor the blind retransmission scheduling of Msg3 initial transmission or has the need to monitor the blind retransmission scheduling of Msg3 initial transmission, the terminal device can start the contention resolution timer immediately after successfully receiving the RAR.

In some embodiments, the method 300 further includes:

After the initial transmission of Msg3 is sent and a first duration has elapsed, a contention resolution timer is started or restarted, wherein the first duration is a round-trip time (RTT) between the terminal device and the network device;

During the running of the contention resolution timer, the PDCCH is monitored, for example, the PDCCH indicating the retransmission of Msg3 scrambled by TC-RNTI is monitored, and whether the contention resolution is unsuccessful is determined according to the monitoring result of the PDCCH.

Optionally, when the initial transmission of Msg3 does not use repeated transmission, the terminal device starts or restarts ra-ContentionResolutionTimer after sending the initial transmission of Msg3 and the first time duration has elapsed.

Optionally, in the case where repeated transmission is used for the initial transmission of Msg3, the terminal device starts or restarts ra-ContentionResolutionTimer after sending all repeated transmissions of Msg3 and the first time duration has elapsed.

In some embodiments, the network device may refer to a network device in a TN system, such as a base station, specifically a gNG, and the first duration may be UE-gNB RTT.

As shown in Figure 8, the terminal device starts the ra-ContentionResolutionTimer immediately after successfully receiving the RAR. After the ra-ContentionResolutionTimer is started, it monitors the PDCCH. Further, after sending the initial transmission of Msg3 and experiencing UE-gNBRTT, the ra-ContentionResolutionTimer is started or restarted. During the operation of the ra-ContentionResolutionTimer, the TC-RNTI encrypted PDCCH indicating the retransmission of Msg3 is monitored.

In summary, in the embodiment of the present application, the terminal device immediately starts the ra-ContentionResolutionTimer after successfully receiving the RAR, and further monitors the PDCCH during the operation of the ra-ContentionResolutionTimer, which is beneficial to avoid missing the PDCCH indicating the blind retransmission scheduling of Msg3.

The above text, in combination with Figures 5 to 8, describes in detail the method embodiment of the present application. The following text, in combination with Figures 9 to 13, describes in detail the device embodiment of the present application. It should be understood that the device embodiment and the method embodiment correspond to each other, and similar descriptions can refer to the method embodiment.

Fig. 9 shows a schematic block diagram of a terminal device 400 according to an embodiment of the present application. As shown in Fig. 9, the terminal device 400 includes:

The processing unit 410 is used to determine whether the contention resolution is unsuccessful according to the start time and/or timeout time of the first contention resolution timer when the first contention resolution timer in the random access process times out.

In some embodiments, the processing unit 410 is further configured to:

If the first condition is met, the contention resolution is not considered unsuccessful, wherein the first condition includes one of the following:

The first contention resolution timer is started immediately after the terminal device sends the initial transmission of message 3.

In some embodiments, the first condition further includes:

After the first contention resolution timer is started, the terminal device does not receive the retransmitted physical downlink control channel PDCCH of the indication message 3 scrambled by the temporary cell radio network temporary identifier TC-RNTI.

In some embodiments, the first condition further includes:

In some embodiments, the processing unit 410 is further configured to:

If the second condition is met, the contention resolution is considered unsuccessful, wherein the second condition includes one of the following:

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 scrambled by the TC-RNTI, and the first contention resolution timer is not started at the moment when the terminal device successfully receives the RAR;

After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of the TC-RNTI-scrambled message 3, and the first contention resolution timer is not started at the moment when the terminal device sends the initial transmission of the message 3;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the TC-RNTI-scrambled indication message 3, and the time of starting the first contention resolution timer is no earlier than the first time unit in the random access process, wherein the first time unit is a time unit after the terminal device sends the initial transmission of message 3 and experiences a first duration, and the first duration is equal to the round-trip delay RTT between the terminal device and the network device;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 encrypted by the TC-RNTI, and the time when the first contention resolution timer times out is no earlier than the first time unit in the random access process, wherein the first time unit is the time unit after the terminal device sends the initial transmission of the message 3 and experiences the first duration, and the first duration is equal to the round-trip delay RTT between the terminal device and the network device;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the TC-RNTI scrambled indication message 3, and the first contention resolution timer is not the contention resolution timer started for the first time in the random access process;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 scrambled by the TC-RNTI, and the terminal device starts the contention resolution timer at the moment of successfully receiving the RAR, and the first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of receiving the RAR;

After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of message 3 encrypted by TC-RNTI, and the terminal device starts the contention resolution timer at the moment of sending the initial transmission of message 3. The first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of sending the initial transmission of message 3.

In some embodiments, the second condition further includes:

In some embodiments, the first contention resolution timer is a timer that was last started or restarted by the terminal device.

In some embodiments, the terminal device is a terminal device in a non-terrestrial network NTN cell.

Optionally, in some embodiments, the communication unit may be a communication interface or a transceiver, or an input/output interface of a communication chip or a system on chip. The processing unit may be one or more processors.

It should be understood that the terminal device 400 according to the embodiment of the present application may correspond to the terminal device in the method embodiment of the present application, and the above-mentioned and other operations and/or functions of each unit in the terminal device 400 are respectively for realizing the corresponding processes of the terminal device in the method 200 shown in Figures 5 to 6, which will not be repeated here for the sake of brevity.

FIG10 is a schematic block diagram of a terminal device according to an embodiment of the present application. The terminal device 500 of FIG10 includes:

The processing unit 510 is configured to start a contention resolution timer immediately after successfully receiving the random access response RAR;

The communication unit 520 is configured to monitor a physical downlink control channel PDCCH during the running of the contention resolution timer.

In some embodiments, the processing unit 510 is further configured to:

At the Mth PDCCH monitoring opportunity after successfully receiving the RAR, start the contention resolution timer, where M is a positive integer; or

The contention resolution timer is started at the Nth time unit after the RAR is successfully received, where N is a positive integer.

In some embodiments, the M is predefined or configured by the network device.

In some embodiments, the N is predefined or configured by a network device. 13. The method according to any one of claims 9 to 12, wherein the terminal device initiates random access to a first cell, and the first cell supports blind retransmission scheduling of initial transmission of message 3.

In some embodiments, the terminal device has the ability to monitor the blind retransmission scheduling of the initial transmission of message 3; and/or,

In some embodiments, the processing unit 510 is further configured to:

After the initial transmission of message 3 is sent and a first duration has elapsed, starting or restarting a contention resolution timer, wherein the first duration is a round-trip time (RTT) between the terminal device and the network device;

The communication unit 520 is further configured to: monitor the PDCCH during the running of the contention resolution timer.

It should be understood that the terminal device 500 according to the embodiment of the present application may correspond to the terminal device in the method embodiment of the present application, and the above-mentioned and other operations and/or functions of each unit in the terminal device 500 are respectively for realizing the corresponding processes of the terminal device in the method 300 shown in Figures 7 to 8, which will not be repeated here for the sake of brevity.

Fig. 11 is a schematic structural diagram of a communication device 600 provided in an embodiment of the present application. The communication device 600 shown in Fig. 11 includes a processor 610, and the processor 610 can call and run a computer program from a memory to implement the method in the embodiment of the present application.

Optionally, as shown in Fig. 11, the communication device 600 may further include a memory 620. The processor 610 may call and run a computer program from the memory 620 to implement the method in the embodiment of the present application.

The memory 620 may be a separate device independent of the processor 610 , or may be integrated into the processor 610 .

Optionally, as shown in FIG. 11 , the communication device 600 may further include a transceiver 630 , and the processor 610 may control the transceiver 630 to communicate with other devices, specifically, may send information or data to other devices, or receive information or data sent by other devices.

The transceiver 630 may include a transmitter and a receiver. The transceiver 630 may further include an antenna, and the number of the antennas may be one or more.

Optionally, the communication device 600 may specifically be a network device of an embodiment of the present application, and the communication device 600 may implement the corresponding processes implemented by the network device in each method of the embodiment of the present application, which will not be described in detail here for the sake of brevity.

Optionally, the communication device 600 may specifically be a mobile terminal/terminal device of an embodiment of the present application, and the communication device 600 may implement the corresponding processes implemented by the mobile terminal/terminal device in each method of the embodiment of the present application, which will not be described in detail here for the sake of brevity.

Fig. 12 is a schematic structural diagram of a chip according to an embodiment of the present application. The chip 700 shown in Fig. 12 includes a processor 710, and the processor 710 can call and run a computer program from a memory to implement the method according to the embodiment of the present application.

Optionally, as shown in Fig. 12, the chip 700 may further include a memory 720. The processor 710 may call and run a computer program from the memory 720 to implement the method in the embodiment of the present application.

The memory 720 may be a separate device independent of the processor 710 , or may be integrated into the processor 710 .

Optionally, the chip 700 may further include an input interface 730. The processor 710 may control the input interface 730 to communicate with other devices or chips, and specifically, may obtain information or data sent by other devices or chips.

Optionally, the chip 700 may further include an output interface 740. The processor 710 may control the output interface 740 to communicate with other devices or chips, and specifically, may output information or data to other devices or chips.

Optionally, the chip can be applied to the network device in the embodiments of the present application, and the chip can implement the corresponding processes implemented by the network device in each method of the embodiments of the present application. For the sake of brevity, they will not be repeated here.

Optionally, the chip can be applied to the mobile terminal/terminal device in the embodiments of the present application, and the chip can implement the corresponding processes implemented by the mobile terminal/terminal device in the various methods of the embodiments of the present application. For the sake of brevity, they will not be repeated here.

It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

FIG13 is a schematic block diagram of a communication system 900 provided in an embodiment of the present application. As shown in FIG13 , the communication system 900 includes a terminal device 910 and a network device 920 .

Among them, the terminal device 910 can be used to implement the corresponding functions implemented by the terminal device in the above method, and the network device 920 can be used to implement the corresponding functions implemented by the network device in the above method. For the sake of brevity, they will not be repeated here.

It should be understood that the processor of the embodiment of the present application may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method embodiment can be completed by the hardware integrated logic circuit in the processor or the instruction in the form of software. The above processor can be a general processor, a digital signal processor (Digital Signal Processor, DSP), an application specific integrated circuit (Application Specific Integrated Circuit, ASIC), a field programmable gate array (Field Programmable Gate Array, FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware decoding processor to perform, or it can be performed by a combination of hardware and software modules in the decoding processor. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

It can be understood that the memory in the embodiment of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and 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.

It should be understood that the above-mentioned memory is exemplary but not restrictive. For example, the memory in the embodiment of the present application may also be static random access memory (static RAM, SRAM), dynamic random access memory (dynamic RAM, 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 (synch link DRAM, SLDRAM) and direct memory bus random access memory (Direct Rambus RAM, DR RAM), etc. That is to say, the memory in the embodiment of the present application is intended to include but not limited to these and any other suitable types of memory.

An embodiment of the present application also provides a computer-readable storage medium for storing a computer program.

Optionally, the computer-readable storage medium can be applied to the network device in the embodiments of the present application, and the computer program enables the computer to execute the corresponding processes implemented by the network device in the various methods of the embodiments of the present application. For the sake of brevity, they are not repeated here.

Optionally, the computer-readable storage medium can be applied to the mobile terminal/terminal device in the embodiments of the present application, and the computer program enables the computer to execute the corresponding processes implemented by the mobile terminal/terminal device in the various methods of the embodiments of the present application. For the sake of brevity, they are not repeated here.

An embodiment of the present application also provides a computer program product, including computer program instructions.

Optionally, the computer program product can be applied to the network device in the embodiments of the present application, and the computer program instructions enable the computer to execute the corresponding processes implemented by the network device in the various methods of the embodiments of the present application. For the sake of brevity, they are not repeated here.

Optionally, the computer program product can be applied to the mobile terminal/terminal device in the embodiments of the present application, and the computer program instructions enable the computer to execute the corresponding processes implemented by the mobile terminal/terminal device in the various methods of the embodiments of the present application. For the sake of brevity, they are not repeated here.

The embodiment of the present application also provides a computer program.

Optionally, the computer program can be applied to the network device in the embodiments of the present application. When the computer program runs on a computer, the computer executes the corresponding processes implemented by the network device in the various methods of the embodiments of the present application. For the sake of brevity, they are not described here.

Optionally, the computer program can be applied to the mobile terminal/terminal device in the embodiments of the present application. When the computer program is run on a computer, the computer executes the corresponding processes implemented by the mobile terminal/terminal device in the various methods of the embodiments of the present application. For the sake of brevity, they are not repeated here.

Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

In the several embodiments provided in the present 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 schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

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

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

A wireless communication method, comprising:

When the first contention resolution timer in the random access process times out, the terminal device determines whether contention resolution is unsuccessful based on the start time and/or timeout time of the first contention resolution timer.
The method according to claim 1 is characterized in that the terminal device determines whether the contention resolution is unsuccessful according to the start time and/or timeout time of the first contention resolution timer, comprising:

When the first condition is met, the terminal device does not consider that the contention resolution is unsuccessful, wherein the first condition includes one of the following:

The first contention resolution timer is a contention resolution timer started for the first time in the random access process;

The first contention resolution timer is started before the first time unit in the random access process, wherein the first time unit is a time unit after the terminal device sends the initial transmission of message 3 and experiences a first duration, and the first duration is equal to the round-trip delay RTT between the terminal device and the network device;

The first contention resolution timer times out before a first time unit in the random access process, wherein the first time unit is a time unit after the terminal device sends the initial transmission of message 3 and experiences a first duration, and the first duration is equal to the RTT between the terminal device and the network device;

The first contention resolution timer is started immediately after the terminal device successfully receives the random access response RAR;

The first contention resolution timer is started immediately after the terminal device completes the initial transmission of message 3.
The method according to claim 2, characterized in that the first condition further comprises:

After the first contention resolution timer is started, the terminal device does not receive the retransmitted physical downlink control channel PDCCH of the indication message 3 scrambled by the temporary cell radio network temporary identifier TC-RNTI.
The method according to claim 2 or 3, characterized in that the first condition further comprises:

The terminal device has the capability of monitoring the blind retransmission scheduling of the initial transmission of message 3; and/or,

The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.
The method according to any one of claims 1 to 4, characterized in that the terminal device determines whether the contention resolution is unsuccessful according to the start time and/or timeout time of the first contention resolution timer, comprising:

When the second condition is met, the terminal device considers that the contention resolution is unsuccessful, wherein the second condition includes one of the following:

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 scrambled by the TC-RNTI, and the first contention resolution timer is not started at the moment when the terminal device successfully receives the RAR;

After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of the TC-RNTI-scrambled message 3, and the first contention resolution timer is not started at the moment when the terminal device sends the initial transmission of the message 3;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the TC-RNTI-scrambled indication message 3, and the time of starting the first contention resolution timer is no earlier than the first time unit in the random access process, wherein the first time unit is a time unit after the terminal device sends the initial transmission of message 3 and experiences a first duration, and the first duration is equal to the round-trip delay RTT between the terminal device and the network device;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 encrypted by the TC-RNTI, and the time when the first contention resolution timer times out is no earlier than the first time unit in the random access process, wherein the first time unit is the time unit after the terminal device sends the initial transmission of the message 3 and experiences the first duration, and the first duration is equal to the round-trip delay RTT between the terminal device and the network device;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the TC-RNTI scrambled indication message 3, and the first contention resolution timer is not the contention resolution timer started for the first time in the random access process;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 scrambled by the TC-RNTI, and the terminal device starts the contention resolution timer at the moment of successfully receiving the RAR, and the first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of receiving the RAR;

After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of message 3 encrypted by TC-RNTI, and the terminal device starts the contention resolution timer at the moment of sending the initial transmission of message 3. The first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of sending the initial transmission of message 3.
The method according to claim 5, characterized in that the second condition further comprises:

The terminal device has the capability of monitoring the blind retransmission scheduling of the initial transmission of message 3; and/or,

The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.
The method according to any one of claims 1-6 is characterized in that the first contention resolution timer is the timer that was most recently started or restarted by the terminal device.
The method according to any one of claims 1-7 is characterized in that the terminal device is a terminal device in a non-terrestrial network NTN cell.
A wireless communication method, comprising:

After successfully receiving the random access response RAR, the terminal device immediately starts the contention resolution timer;

During the running of the contention resolution timer, a physical downlink control channel PDCCH is monitored.
The method according to claim 9 is characterized in that the terminal device immediately starts a contention resolution timer after successfully receiving a random access response RAR, comprising:

The terminal device starts the contention resolution timer at the Mth PDCCH monitoring opportunity after successfully receiving the RAR, where M is a positive integer; or

The terminal device starts a contention resolution timer at the Nth time unit after successfully receiving the RAR, where N is a positive integer.
The method according to claim 10 is characterized in that M is predefined or configured by the network device.
The method according to claim 10 is characterized in that N is predefined or configured by the network device.
The method according to any one of claims 9-12 is characterized in that the terminal device initiates random access to the first cell, and the first cell supports blind retransmission scheduling of the initial transmission of message 3.
The method according to any one of claims 9 to 13, characterized in that

The terminal device has the capability of monitoring the blind retransmission scheduling of the initial transmission of message 3; and/or,

The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.
The method according to any one of claims 9 to 14, characterized in that the method further comprises:

After the initial transmission of message 3 is sent and a first duration has elapsed, starting or restarting a contention resolution timer, wherein the first duration is a round-trip time (RTT) between the terminal device and the network device;

While the contention resolution timer is running, the PDCCH is monitored.
The method according to any one of claims 9 to 15 is characterized in that the terminal device is a terminal device in a non-terrestrial network NTN cell.
A terminal device, characterized by comprising:

The processing unit is used to determine whether contention resolution is unsuccessful according to the start time and/or timeout time of the first contention resolution timer when the first contention resolution timer in the random access process times out.
The terminal device according to claim 17, characterized in that the processing unit is further used for:

If the first condition is met, the contention resolution is not considered unsuccessful, wherein the first condition includes one of the following:

The first contention resolution timer is a contention resolution timer started for the first time in the random access process;

The first contention resolution timer is started before the first time unit in the random access process, wherein the first time unit is a time unit after the terminal device sends the initial transmission of message 3 and experiences a first duration, and the first duration is equal to the round-trip delay RTT between the terminal device and the network device;

The first contention resolution timer times out before a first time unit in the random access process, wherein the first time unit is a time unit after the terminal device sends the initial transmission of message 3 and experiences a first duration, and the first duration is equal to the RTT between the terminal device and the network device;

The first contention resolution timer is started immediately after the terminal device successfully receives the random access response RAR;

The first contention resolution timer is started immediately after the terminal device completes the initial transmission of message 3.
The terminal device according to claim 18, wherein the first condition further comprises:

After the first contention resolution timer is started, the terminal device does not receive the retransmitted physical downlink control channel PDCCH of the indication message 3 scrambled by the temporary cell radio network temporary identifier TC-RNTI.
The terminal device according to claim 18 or 19, characterized in that the first condition further comprises:

The terminal device has the capability of monitoring the blind retransmission scheduling of the initial transmission of message 3; and/or,

The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.
The terminal device according to any one of claims 17 to 20, characterized in that the processing unit is further used for:

If the second condition is met, the contention resolution is considered unsuccessful, wherein the second condition includes one of the following:

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 scrambled by the TC-RNTI, and the first contention resolution timer is not started at the moment when the terminal device successfully receives the RAR;

After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of the TC-RNTI-scrambled message 3, and the first contention resolution timer is not started at the moment when the terminal device sends the initial transmission of the message 3;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 encrypted by the TC-RNTI, and the time of starting the first contention resolution timer is no earlier than the first time unit in the random access process, wherein the first time unit is the time unit after the terminal device sends the initial transmission of the message 3 and experiences the first duration, and the first duration is equal to the round-trip delay RTT between the terminal device and the network device;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 encrypted by the TC-RNTI, and the time when the first contention resolution timer times out is no earlier than the first time unit in the random access process, wherein the first time unit is the time unit after the terminal device sends the initial transmission of the message 3 and experiences the first duration, and the first duration is equal to the round-trip delay RTT between the terminal device and the network device;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the TC-RNTI scrambled indication message 3, and the first contention resolution timer is not the contention resolution timer started for the first time in the random access process;

After the first contention resolution timer is started, the terminal device does not receive the PDCCH of the retransmission of the indication message 3 scrambled by the TC-RNTI, and the terminal device starts the contention resolution timer at the moment of successfully receiving the RAR, and the first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of receiving the RAR;

After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of message 3 encrypted by TC-RNTI, and the terminal device starts the contention resolution timer at the moment of sending the initial transmission of message 3. The first contention resolution timer is not the contention resolution timer started by the terminal device at the moment of sending the initial transmission of message 3.
The terminal device according to claim 21, characterized in that the second condition further comprises:

The terminal device has the capability of monitoring the blind retransmission scheduling of the initial transmission of message 3; and/or,

The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.
The terminal device according to any one of claims 17-22 is characterized in that the first contention resolution timer is the timer that was most recently started or restarted by the terminal device.
The terminal device according to any one of claims 17-23 is characterized in that the terminal device is a terminal device in a non-terrestrial network NTN cell.
A terminal device, characterized by comprising:

A processing unit, configured to start a contention resolution timer immediately after successfully receiving a random access response RAR;

The communication unit is used to monitor the physical downlink control channel PDCCH during the operation of the contention resolution timer.
The terminal device according to claim 25, characterized in that the processing unit is further used for:

At the Mth PDCCH monitoring opportunity after successfully receiving the RAR, start the contention resolution timer, where M is a positive integer; or

The contention resolution timer is started at the Nth time unit after the RAR is successfully received, where N is a positive integer.
The terminal device according to claim 26 is characterized in that M is predefined or configured by the network device.
The terminal device according to claim 26 is characterized in that N is predefined or configured by the network device.
The terminal device according to any one of claims 25-28 is characterized in that the terminal device initiates random access to a first cell, and the first cell supports blind retransmission scheduling of initial transmission of message 3.
The terminal device according to any one of claims 25 to 29, characterized in that:

The terminal device has the capability of monitoring the blind retransmission scheduling of the initial transmission of message 3; and/or,

The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.
The terminal device according to any one of claims 25 to 30, characterized in that the processing unit is further used for:

After the initial transmission of message 3 is sent and a first duration has elapsed, starting or restarting a contention resolution timer, wherein the first duration is a round-trip time (RTT) between the terminal device and the network device;

The communication unit is further configured to: monitor the PDCCH during the running of the contention resolution timer.
The terminal device according to any one of claims 25-31 is characterized in that the terminal device is a terminal device in a non-terrestrial network NTN cell.
A terminal device, characterized in that it comprises: a processor and a memory, the memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to execute the method as described in any one of claims 1 to 8, or the method as described in any one of claims 9 to 16.
A chip, characterized in that it comprises: a processor, used to call and run a computer program from a memory, so that a device equipped with the chip executes the method as described in any one of claims 1 to 8, or the method as described in any one of claims 9 to 16.
A computer-readable storage medium, characterized in that it is used to store a computer program, wherein the computer program enables a computer to execute the method according to any one of claims 1 to 8, or the method according to any one of claims 9 to 16.
A computer program product, characterized in that it comprises computer program instructions, wherein the computer program instructions enable a computer to execute the method according to any one of claims 1 to 8, or the method according to any one of claims 9 to 16.
A computer program, characterized in that the computer program enables a computer to execute the method according to any one of claims 1 to 8, or the method according to any one of claims 9 to 16.