Wireless communication method and terminal equipment

Abstract

A wireless communication method and a terminal device, the method comprising: when a first contention resolution timer is overtime in a random access process, the terminal device determining whether contention resolution is unsuccessful according to a starting time and / or an overtime time of the first contention resolution timer.

Description

Wireless communication method and terminal device Technical Field

[0001] The embodiments of the present application relate to the field of communications, and specifically to a method and terminal device for wireless communication. Background Art

[0002] In the New Radio (NR) system, a four-step random access process is supported, in which the terminal device starts a 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 operation of the ra-ContentionResolutionTimer.

[0003] In non-terrestrial networks (NTN) systems, due to the large transmission delay between terminal devices and network devices, in order to avoid invalid PDCCH monitoring caused by prematurely starting the ra-ContentionResolutionTimer, it is considered to increase the start time of the ra-ContentionResolutionTimer by a delay offset equal to 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 no PDCCH indicating the retransmission of Msg3 is received, the terminal device will believe that contention resolution has failed, affecting random access efficiency. Therefore, how to perform random access to improve random access efficiency is an urgent problem that needs to be solved.

[0004] Summary of the Invention

[0005] The present application provides a wireless communication method and terminal device, which are conducive to improving random access efficiency.

[0006] 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 based on a start time and / or a timeout time of the first contention resolution timer.

[0007] In a second aspect, a wireless communication method is provided, comprising: after successfully receiving a random access response RAR, the terminal device immediately starts a contention resolution timer; and during the operation of the contention resolution timer, monitors a physical downlink control channel PDCCH.

[0008] In a third aspect, a terminal device is provided for executing the method in the above-mentioned first aspect or its various implementations.

[0009] Specifically, the terminal device includes a functional module for executing the method in the above-mentioned first aspect or its various implementation modes.

[0010] In a fourth aspect, a terminal device is provided for executing the method in the above-mentioned second aspect or its various implementation modes.

[0011] Specifically, the terminal device includes a functional module for executing the method in the above-mentioned second aspect or its various implementation modes.

[0012] In a fifth aspect, a terminal device is provided, comprising a processor and a memory, wherein the memory is configured to store a computer program, and the processor is configured to call and execute the computer program stored in the memory to perform the method of the first aspect or its respective implementations.

[0013] In a sixth aspect, a terminal device is provided, comprising a processor and a memory, wherein the memory is configured to store a computer program, and the processor is configured to call and execute the computer program stored in the memory to perform the method of the second aspect or its respective implementations.

[0014] In a seventh aspect, a chip is provided for implementing the method in any one of the first to second aspects or their respective implementations.

[0015] Specifically, the chip includes: a processor for calling and running a computer program from a memory, so that a device equipped with the device executes the method in any one of the first to second aspects or their respective implementations.

[0016] In an eighth aspect, a computer-readable storage medium is provided for storing a computer program, which enables a computer to execute the method of any one of the first to second aspects or their respective implementations.

[0017] 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 of any one of the first to second aspects or their respective implementations.

[0018] In a tenth aspect, a computer program is provided, which, when executed on a computer, enables the computer to execute the method of any one of the first to second aspects or their respective implementations.

[0019] 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 conducive to avoiding misjudgment of the contention resolution result, thereby causing the terminal device to need to retry random access, affecting the efficiency of random access. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG1A is a schematic diagram of a communication system architecture provided in an embodiment of the present application.

[0021] FIG1B is a schematic diagram of another communication system architecture provided in an embodiment of the present application.

[0022] FIG1C is a schematic diagram of another communication system architecture provided in an embodiment of the present application.

[0023] Figure 2 is a network architecture diagram of NTN based on transparent data satellite.

[0024] FIG3 is a network architecture diagram of NTN based on regenerative data satellites.

[0025] FIG4 is a schematic flowchart of a four-step contention-based random access process.

[0026] FIG5 is a schematic diagram of a wireless communication method provided according to an embodiment of the present application.

[0027] FIG6 is a schematic diagram of a method for determining contention resolution according to an embodiment of the present application.

[0028] FIG7 is a schematic diagram of another wireless communication method provided according to an embodiment of the present application.

[0029] FIG8 is a schematic diagram of a method for starting a contention resolution timer according to an embodiment of the present application.

[0030] FIG9 is a schematic block diagram of a terminal device provided according to an embodiment of the present application.

[0031] FIG10 is a schematic block diagram of another terminal device provided according to an embodiment of the present application.

[0032] FIG11 is a schematic block diagram of a communication device provided according to an embodiment of the present application.

[0033] FIG12 is a schematic block diagram of a chip provided according to an embodiment of the present application.

[0034] FIG13 is a schematic block diagram of a communication system provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0035] The following will describe the technical solutions in the embodiments of this application in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of the embodiments. With respect to the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0036] 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, NR system evolution system, LTE on unlicensed spectrum (LTE-U) system, NR on unlicensed spectrum (NR-U) system, Non-Terrestrial Networks (NTN) system, Universal Mobile Telecommunication System (UMTS), Wireless Local Area Networks (WLAN), Wireless Fidelity (Wireless Fidelity) system. Fidelity, WiFi), fifth-generation communication (5th-Generation, 5G) system or other communication systems, etc.

[0037] 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 (D2D) communication, machine-to-machine (M2M) 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.

[0038] The communication system in the embodiment of the present application can be applied to a carrier aggregation (CA) scenario, a dual connectivity (DC) scenario, and a standalone (SA) networking scenario.

[0039] The communication system in the embodiment of the present application can be applied to an unlicensed spectrum, where 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, where the authorized spectrum can also be considered as an unshared spectrum.

[0040] The embodiments of the present application can be applied to non-terrestrial networks (NTN) systems, and can also be applied to terrestrial networks (TN) systems.

[0041] As an example, NTN systems include, but are not limited to, New Radio NTN (NR-NTN) systems and Internet of Things NTN (IoT-NTN) systems. The IoT-NTN system can include Narrow Band Internet of Things over NTN (NB-IoT-NTN) systems and Enhanced Machine Type Communication over NTN (eMTC-NTN) systems.

[0042] The embodiments of the present application describe various embodiments in conjunction with network devices and terminal devices, wherein the terminal device 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 device, user agent or user device, etc.

[0043] 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 capabilities, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal device in a next-generation communication system such as an NR network, or a terminal device in a future evolved Public Land Mobile Network (PLMN) network, etc.

[0044] In an embodiment 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 (such as airplanes, balloons and satellites, etc.).

[0045] 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, 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.

[0046] As an example and not a limitation, in the embodiment of the present application, the terminal device may also be a wearable device. Wearable devices may also be called 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 achieve powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include those that are fully functional, large in size, and can achieve complete or partial functions without relying on smartphones, such as smart watches or smart glasses, as well as those 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 smart bracelets and smart jewelry for vital sign monitoring.

[0047] 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 (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.

[0048] As an example and not a 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.

[0049] In an embodiment of the present application, the network device can provide services for a cell, and the terminal device communicates with the network device through the transmission resources used by the cell (for example, frequency domain resources, or spectrum resources). The cell can be a cell corresponding to the network device (for example, a base station). 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.

[0050] For example, Figure 1A is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application. As shown in Figure 1A, the communication system 100 may include a network device 110, which may be a device that communicates with a terminal device 120 (or also referred to as a communication terminal or terminal). The network device 110 may provide communication coverage for a specific geographic area and may communicate with terminal devices located within the coverage area.

[0051] Figure 1A 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.

[0052] For example, FIG1B is a schematic diagram of the architecture of another communication system provided in an embodiment of the present application. Referring to FIG1B , a terminal device 1101 and a satellite 1102 are included, 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 an 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. In 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 area, which is not limited in the embodiments of the present application.

[0053] For example, 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 an 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 each network device 1203 may include other number of terminal devices within its coverage area, which is not limited in the embodiments of the present application.

[0054] It should be noted that Figures 1A-1C are only examples of the system to which this application is applicable. Of course, the method shown in the embodiment of this application can also be applied to other systems, such as 5G communication systems, LTE communication systems, etc., and the embodiment of this application does not make specific limitations on this.

[0055] 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 (MME) and an Access and Mobility Management Function (AMF), but the embodiments of the present application are not limited to this.

[0056] It should be understood that in the embodiments of the present application, a device having a communication function in a network / system may be referred to as a communication device. Taking the communication system 100 shown in FIG1A as an example, the communication device may include a network device 110 and a terminal device 120 having a communication function. The network device 110 and the terminal device 120 may be the specific devices described above and will not be described in detail here. The communication device may also include other devices in the communication system 100, such as a network controller, a mobility management entity, and other network entities, which are not limited in the embodiments of the present application.

[0057] It should be understood that the terms "system" and "network" are often used interchangeably herein. The term "and / or" is simply a description of an association between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " generally indicates that the related objects are in an "or" relationship.

[0058] It should be understood that the "indication" mentioned in the embodiments of this application can be a direct indication, an indirect indication, or an indication of an association. For example, "A indicates B" 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 between A and B.

[0059] In the description of the embodiments of the present application, the term "corresponding" may indicate a direct or indirect correspondence between the two, or an association relationship between the two, or a relationship between indication and being indicated, configuration and being configured, etc.

[0060] In some embodiments of the present application, "predefined" may be implemented by pre-storing corresponding codes, tables, or other methods that can be used to indicate relevant information in a device (e.g., a terminal device or a network device). This application does not limit the specific implementation method. For example, predefined may refer to information defined in a protocol.

[0061] In some embodiments of the present application, the "protocol" may refer to a standard protocol in the field of communications, for example, it may include an LTE protocol, an NR protocol, and related protocols used in future communication systems, and this application does not limit this.

[0062] The main application scenarios of NR include: Enhanced Mobile Broadband (eMBB), Ultra-Reliable and Low Latency Communication (URLLC), and massive machine type of communication (mMTC).

[0063] In the embodiment of the present application, NR can also be deployed independently. In order to reduce air interface signaling and quickly restore wireless connections and data services in the 5G network environment, a new radio resource control (RRC) state is defined, namely the RRC_INACTIVE state. This state is different from the RRC_IDLE and RRC_CONNECTED states.

[0064] In the RRC_IDLE state, mobility is based on cell selection and reselection by 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 no RRC connection exists.

[0065] In the RRC_CONNECTED state, an RRC connection exists, and a device AS context exists between the base station and the terminal. The network knows the terminal's location at the cell level. Mobility is controlled by the network. Unicast data can be transmitted between the terminal and the base station.

[0066] RRC_INACTIVE: Mobility is based on cell selection and reselection of the terminal device. There is a connection between CN and NR. The AS context of the terminal device exists on a certain base station. 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.

[0067] In some scenarios, research is underway into non-terrestrial network (NTN) technology. NTNs typically use satellite communications to provide communications services to users on the ground. Compared to terrestrial cellular networks, satellite communications offer many unique advantages. First, satellite communications are not restricted by user location. For example, conventional terrestrial communications cannot cover areas such as oceans, high mountains, and deserts where communications equipment cannot be deployed or where there is a sparse population. However, satellite communications, on the other hand, can cover a large area with a single satellite and orbit the Earth, so theoretically, every corner of the globe can be covered. Second, satellite communications have significant social value. Satellite communications can provide low-cost coverage in remote mountainous areas and poor, underdeveloped countries or regions, enabling people in these areas to enjoy advanced voice communications and mobile internet technologies, helping to narrow the digital divide with developed regions and promoting their development. Third, satellite communications offer long range, and increasing communication distance does not significantly increase costs. Finally, satellite communications are highly stable and unaffected by natural disasters.

[0068] 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.

[0069] LEO satellites have an altitude range of 500 km to 1500 km, corresponding to an orbital period of approximately 1.5 to 2 hours. Signal propagation delay for single-hop communication between users is typically less than 20 milliseconds, and the maximum satellite visibility time is 20 minutes. The short signal propagation distance and low link loss reduce the transmit power requirements of user terminals.

[0070] The GEO orbit is at an altitude of 35,786 km and revolves around the Earth every 24 hours. The signal propagation delay for single-hop communication between users is typically 250 milliseconds.

[0071] 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.

[0072] FIG2 and FIG3 show two NTN network architectures, wherein FIG2 is an NTN network architecture based on transparent forwarding, and FIG3 is an NTN network architecture based on regenerative forwarding.

[0073] The NTN network can include one or more gateways, which connect satellites to the terrestrial public network. For NTN networks based on transparent forwarding, communication between the gateway and satellite occurs via feeder links, while communication between the satellite and the terminal occurs via service links. For NTN networks based on regenerative forwarding, satellites communicate with each other via intersatellite links, while communication between the gateway and satellite occurs via feeder links, and communication between the satellite and the terminal occurs via service links.

[0074] In transparent forwarding, the satellite only provides the functions of wireless frequency filtering, frequency conversion and amplification. It only provides transparent forwarding of the signal and does not change the waveform signal it forwards.

[0075] In regenerative forwarding, the satellite not only provides wireless frequency filtering, frequency conversion and amplification functions, but also can provide demodulation / decoding, routing / conversion, encoding / modulation functions. It has some or all of the functions of a base station.

[0076] In the NR system, the random access process is mainly triggered by the following events:

[0077] The UE establishes a wireless connection when it initially accesses the network: the UE changes from the RRC_IDLE state to the RRC_CONNECTED state;

[0078] Radio Resource Control (RRC) connection reestablishment process: to enable the UE to reestablish the radio connection after a radio link failure;

[0079] Handover: The UE needs to establish uplink synchronization with the new cell;

[0080] In the RRC_CONNECTED state, downlink data arrives, and the uplink is out of sync.

[0081] In the RRC_CONNECTED state, uplink data arrives, and the uplink is out of sync or there are no PUCCH resources for sending SR.

[0082] Scheduling Request (SR) failed;

[0083] Synchronous reconfiguration request from RRC;

[0084] The UE transitions from the RRC_INACTIVE state to the RRC_CONNECTED state;

[0085] Establishing time alignment during the secondary cell (SCell) addition process;

[0086] Request additional system information (SI);

[0087] Beam failure recovery.

[0088] In the NR system, a four-step random access process is supported, specifically including the sending process of message 1 (Msg1) to message 4 (Msg4). As an example, as shown in Figure 4, the four-step random access process includes the following steps:

[0089] Step 1: The terminal device sends a random access preamble (Preamble, also known as Msg 1) to the network device.

[0090] The random access preamble may also be referred to as a preamble, a random access preamble sequence, a preamble sequence, etc.

[0091] Specifically, the terminal device may select a physical random access channel (PRACH) resource and send a selected preamble on the selected PRACH.

[0092] Based on the Preamble, the network device can estimate the uplink timing and the grant size required for the terminal device to transmit Msg3.

[0093] Step 2: The network device sends a Random Access Response (RAR, also known as Msg 2) to the terminal device.

[0094] After the terminal device sends the Preamble to the network device, it can open a random access response window (ra-ResponseWindow) and monitor the physical downlink control channel (PDCCH) encrypted by the random access radio network temporary identifier (RA-RNTI) within 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 sends the Preamble, including the RAR, the RAR may include the following information:

[0095] The RAR subheader contains BI, which is used to indicate the backoff time for retransmitting Msg1;

[0096] RAPID in RAR: Preamble index received in response from the network device;

[0097] The RAR payload contains a Timing Advance Group (TAG), which is used to adjust the uplink timing.

[0098] Uplink grant (UL grant): used to schedule uplink resource indication of Msg3;

[0099] Temporary Cell RNTI (TC-RNTI): used to scramble the PDCCH of Msg4 (initial access).

[0100] If the terminal receives the 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.

[0101] Step 3: The terminal device sends Msg 3.

[0102] Msg 3 is mainly used to notify the network device of the random access triggering event. For different random access triggering events, the Msg 3 sent by the terminal device in step 3 may include different content.

[0103] For example, for an RRC connection reestablishment scenario, Msg 3 may include the establishment cause and the UE identity.

[0104] 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.

[0105] In step 4, the network device sends a contention resolution message (Msg 4) to the terminal device.

[0106] Msg4 has two functions: one is used for contention conflict resolution, and the second is for the network device to transmit RRC configuration messages to the terminal device. Contention conflict resolution can be done in the following two ways:

[0107] Method 1: If the terminal device carries C-RNTI in Msg3, Msg4 is scheduled using PDCCH scrambled with C-RNTI.

[0108] Method 2: If the terminal device does not carry C-RNTI in Msg3, such as initial access, Msg4 is scheduled with PDCCH scrambled by TC-RNTI. At this time, the conflict is resolved by the UE receiving the PDSCH of Msg4, obtaining the conflict resolution ID, and determining whether the conflict is resolved by matching the conflict resolution ID with the common control channel (CCCH) service data unit (SDU) in Msg 3.

[0109] The random access process described above demonstrates that its primary purpose is to achieve uplink synchronization between the terminal device and the cell. During random access, the network device determines the time the terminal device transmits the preamble based on the RACH time-frequency resources used to receive the preamble from the terminal device. This information then determines the terminal device's initial TA based on the preamble's transmission and reception times, and notifies the terminal device via the RAR.

[0110] In a TN system, a terminal device immediately starts the ra-ContentionResolutionTimer after each Msg3 transmission (including initial and retransmissions). The terminal device monitors the PDCCH during the ra-ContentionResolutionTimer. The terminal device must wait at least one round-trip time (RTT) between sending Msg3 and receiving Msg4. Because the signal transmission delay between the network and the terminal device in an NTN system is much greater than that in a TN system (for example, in a GEO scenario, the RTT can be as long as 541.46 ms), to prevent invalid PDCCH monitoring caused by prematurely starting the ra-ContentionResolutionTimer, the ra-ContentionResolutionTimer start time in the NTN system is considered to be offset by a delay equal to the UE-gNB RTT compared to that in the TN system. However, this design will prevent the terminal device from receiving blind retransmissions scheduled for the initial Msg3 transmission.

[0111] To enable the terminal to monitor the blind scheduling retransmission grant for the initial Msg3 transmission, consider starting the ra-ContentionResolutionTimer immediately after completing the initial Msg3 transmission. Since the terminal next starts or restarts the ra-ContentionResolutionTimer after completing the initial Msg3 transmission plus one UE-gNB RTT, it is possible that the previously running ra-ContentionResolutionTimer will expire before the terminal next starts or restarts the ra-ContentionResolutionTimer. If the terminal does not receive a TC-RNTI-scrambled PDCCH indicating a retransmission of Msg3 after the ra-ContentionResolutionTimer starts, the terminal will consider contention resolution to have failed and must retry random access. After sending the initial Msg3 transmission and experiencing a delay of one UE-gNB RTT, the terminal should resume monitoring for the scheduling of Msg4. It should not prematurely determine that contention resolution has failed, which would affect random access efficiency. Therefore, how to perform random access to improve random access efficiency is an urgent issue that needs to be addressed.

[0112] 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 combined arbitrarily with the technical solutions of the embodiments of the present application as optional solutions, and all of them fall within the scope of protection of the embodiments of the present application. The embodiments of the present application include at least part of the following contents.

[0113] FIG5 is a schematic flow chart of a wireless communication method 200 according to an embodiment of the present application. As shown in FIG5 , the method 200 includes the following contents:

[0114] 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 whether the contention resolution fails, based on the start time and / or timeout time of the first contention resolution timer.

[0115] 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 is beneficial 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.

[0116] In some embodiments, the cell that the terminal device initiates the random access procedure to access is an NTN cell, or the terminal device is a terminal device in an NTN cell.

[0117] In some embodiments, the first contention resolution timer is the contention resolution timer that was most recently started or restarted by the terminal device.

[0118] In some embodiments, the start time of the first contention resolution timer refers to the time unit at which the first contention resolution timer is started, such as the symbol or time slot at which the first contention resolution timer is started, or the absolute time at which the first contention resolution timer is started. Similarly, the expiration time of the first contention resolution timer refers to the time unit at which the first contention resolution timer times out, such as the symbol or time slot at which the first contention resolution timer times out, or the absolute time at which the first contention resolution timer times out.

[0119] In some embodiments, the start condition of the ra-ContentionResolutionTimer may include at least one of the following:

[0120] Start Condition 1: During random access, the terminal device starts the ra-ContentionResolutionTimer immediately after successfully receiving the RAR. Starting the ra-ContentionResolutionTimer based on this condition helps avoid missing blind retransmissions scheduled for the initial Msg3 transmission, or in other words, helps the terminal device receive blind retransmissions scheduled for the initial Msg3 transmission.

[0121] 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.

[0122] 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.

[0123] Optionally, the M is predefined or configured by the network device.

[0124] Optionally, N is predefined or configured by the network device.

[0125] Optionally, the Nth time unit may be the Nth symbol, the Nth time slot, etc., which is not limited in this application.

[0126] Start Condition 2: During random access, the terminal device starts the ra-ContentionResolutionTimer immediately after sending the initial transmission of Msg3. Starting the ra-ContentionResolutionTimer based on this condition helps avoid missing blind retransmissions scheduled for the initial Msg3 transmission, or in other words, helps the terminal receive blind retransmissions scheduled for the initial Msg3 transmission.

[0127] 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.

[0128] For another example, when repeated transmission is used for the initial transmission of Msg3, the terminal device immediately starts the ra-ContentionResolutionTimer at the first symbol after sending all repeated transmissions of Msg3.

[0129] Start condition 3: During a random access procedure, the terminal device starts the ra-ContentionResolutionTimer in the first time unit of the random access procedure. The first time unit is the time unit after the terminal device sends the initial transmission of message 3 and a first duration elapses, where the first duration is equal to the RTT between the terminal device and the network device.

[0130] For example, when repeated transmission is not used for the initial transmission of Msg3, the terminal device starts the ra-ContentionResolutionTimer after sending the initial transmission of Msg3 and the first duration has elapsed.

[0131] 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.

[0132] In some embodiments, the network device may refer to a network device in an NTN system, such as a ground base station, specifically a gNB, and the first duration may be a UE-gNB RTT.

[0133] In some embodiments, the terminal device may monitor the PDCCH during the running of the ra-ContentionResolutionTimer, for example, monitor the TC-RNTI scrambled PDCCH indicating the retransmission of Msg3.

[0134] 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 encryption 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.

[0135] Therefore, in some embodiments, the S210 includes:

[0136] 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 whether it is the time when the initial transmission of Msg3 is completed, or whether it is earlier than the first time unit; or

[0137] 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

[0138] When the first contention resolution timer times out, the terminal device determines whether contention resolution is unsuccessful based on whether the timeout period of the first contention resolution timer is earlier than the first time unit; or

[0139] 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 timeout time of the first contention resolution timer is earlier than the first time unit.

[0140] In some embodiments, the terminal device determines whether contention resolution is unsuccessful based on the start time and / or timeout time of the first contention resolution timer, including:

[0141] If a first condition is met, the terminal device does not consider contention resolution unsuccessful, wherein the first condition includes one of the following:

[0142] The first contention resolution timer is a contention resolution timer started for the first time during the random access process;

[0143] The first contention resolution timer is started before a first time unit in the random access process, wherein the first time unit is a time unit after the terminal device completes 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;

[0144] 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 completes the initial transmission of message 3 and a first duration has elapsed, and the first duration is equal to the RTT between the terminal device and the network device;

[0145] The first contention resolution timer is started immediately after the terminal device successfully receives the random access response RAR;

[0146] The first contention resolution timer is started immediately after the terminal device completes the initial transmission of message 3.

[0147] 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.

[0148] 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:

[0149] The terminal device starts the first contention resolution timer at the Mth PDCCH monitoring opportunity after successfully receiving the RAR; or

[0150] The terminal device starts the first contention resolution timer in the Nth time unit after successfully receiving the RAR.

[0151] The specific implementation of M, M, and time units refers to the relevant description in the aforementioned starting condition 1, and is not repeated here for the sake of brevity.

[0152] 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:

[0153] If repeated transmission is not used for the initial transmission of Msg3, the first contention resolution timer is started at the first symbol after the terminal device sends the initial transmission of Msg3; or

[0154] If repeated transmission is used for the initial transmission of Msg3, 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.

[0155] In some embodiments, the first condition further includes:

[0156] After the first contention resolution timer is started, the terminal device does not receive the TC-RNTI-scrambled PDCCH indicating the retransmission of Msg3.

[0157] In some embodiments, the first condition further includes:

[0158] The terminal device has the ability to monitor the blind retransmission scheduling of the initial transmission of message 3; and / or,

[0159] The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.

[0160] That is, the first condition may include one of the following conditions:

[0161] 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 retransmission of Msg3;

[0162] 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 retransmission of Msg3;

[0163] The first contention resolution timer times out before the first time unit in the random access procedure, 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;

[0164] 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 TC-RNTI scrambled PDCCH indicating the retransmission of Msg3;

[0165] 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 TC-RNTI encrypted PDCCH indicating the retransmission of Msg3.

[0166] In some other embodiments, the first condition may include one of the following conditions:

[0167] 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 during the random access process;

[0168] 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;

[0169] 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 the first time unit in the random access process;

[0170] 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 started immediately after the terminal device successfully receives the RAR;

[0171] For a terminal device having the capability of monitoring blind retransmission scheduling of the initial transmission of Msg3 and / or having the requirement of monitoring blind retransmission scheduling of the initial transmission of Msg3, the first contention resolution timer is started immediately after the terminal device sends the initial transmission of Msg3.

[0172] In some further embodiments, the first condition may include one of the following conditions:

[0173] 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;

[0174] 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 an Msg3 retransmission;

[0175] 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 expires before the first time unit in the random access procedure, 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;

[0176] 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 an Msg3 retransmission;

[0177] For a terminal device having the capability of blind retransmission scheduling for monitoring the initial transmission of Msg3 and / or having the requirement of blind retransmission scheduling for monitoring the 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.

[0178] In some embodiments, the terminal device determines whether contention resolution is unsuccessful based on the start time and / or timeout time of the first contention resolution timer, including:

[0179] If the second condition is met, the terminal device considers that the contention resolution is unsuccessful, wherein the second condition includes one of the following:

[0180] 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;

[0181] After the first contention resolution timer is started, the terminal device has not received the TC-RNTI scrambled PDCCH indicating the retransmission of Msg3, and the first contention resolution timer is not started at the moment when the terminal device completes the initial transmission of Msg3;

[0182] After the first contention resolution timer is started, the terminal device does not receive the TC-RNTI-scrambled PDCCH indicating the retransmission of Msg3, 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 Msg3 and experiences a first duration, and the first duration is equal to the RTT between the terminal device and the network device;

[0183] After the first contention resolution timer is started, the terminal device does not receive the TC-RNTI-scrambled PDCCH indicating the retransmission of Msg3, and the time when the first contention resolution timer expires 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;

[0184] After the first contention resolution timer is started, the terminal device does not receive a PDCCH indicating retransmission of Msg3 scrambled by TC-RNTI, and the first contention resolution timer is not a contention resolution timer started for the first time in the random access process;

[0185] 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;

[0186] After the first contention resolution timer is started, the terminal device has not received the TC-RNTI encrypted PDCCH indicating the 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.

[0187] 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.

[0188] For example, the first contention resolution timer is not started at the Mth PDCCH monitoring opportunity after the terminal device successfully receives the RAR.

[0189] For another example, the first contention resolution timer is not started at the Nth time unit after the terminal device successfully receives the RAR.

[0190] 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.

[0191] For example, if repeated transmission is not used in the initial transmission of Msg3, the first contention resolution timer is not started at the first symbol after the terminal device sends the initial transmission of Msg3.

[0192] For another example, if repeated transmission is used for the initial transmission of Msg3, 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.

[0193] 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 is described in the previous text and will not be repeated here.

[0194] 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 is described in the previous text and will not be repeated here.

[0195] In some embodiments, the second condition further includes:

[0196] The terminal device has the ability to monitor the blind retransmission scheduling of the initial transmission of message 3; and / or,

[0197] The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.

[0198] That is, the second condition may include one of the following conditions:

[0199] 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;

[0200] For a terminal device having a blind retransmission scheduling capability and / or a blind retransmission scheduling requirement for 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 the initial transmission of Msg3;

[0201] 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 of starting the first contention resolution timer is no earlier than the first time unit in the random access process;

[0202] 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 an Msg3 retransmission, and the time when the first contention resolution timer expires is no earlier than the first time unit in the random access process;

[0203] 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 the contention resolution timer started for the first time in the random access process;

[0204] 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;

[0205] For a terminal device having the capability of monitoring blind retransmission scheduling of the initial transmission of Msg3 and / or having the requirement of monitoring blind retransmission scheduling of the initial transmission of Msg3, after the first contention resolution timer is started, the terminal device has not received the TC-RNTI-scrambled PDCCH indicating the 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.

[0206] In some embodiments, if the second condition is met, the terminal device discards the TC-RNTI.

[0207] In conjunction with the example shown in Figure 6 , the terminal device immediately starts the ra-ContentionResolutionTimer after sending the initial transmission of Msg3. Specifically, the ra-ContentionResolutionTimer is started at time t1, and the time elapsed from t1 to UE-gNBRTT 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 previously started ra-ContentionResolutionTimer has timed out. Because the start time or timeout time of the ra-ContentionResolutionTimer is before time t3, the terminal device does not consider contention resolution to have failed. Furthermore, at time t3, the terminal device starts or restarts the ra-ContentionResolutionTimer. While the ra-ContentionResolutionTimer is running, the terminal device monitors the TC-RNTI-scrambled PDCCH indicating the retransmission of Msg3 and determines whether contention resolution has failed based on the reception of this PDCCH.

[0208] In summary, when the ra-ContentionResolutionTimer times out, the terminal device can determine whether contention resolution is unsuccessful, or in other words, whether contention resolution has failed, based on the start time and / or timeout time of the ra-ContentionResolutionTimer.

[0209] In some implementations, when the first condition is met, the terminal device does not consider the contention resolution to be unsuccessful.

[0210] 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.

[0211] In some other implementations, when the second condition is met, the terminal device considers that the contention resolution is unsuccessful.

[0212] 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.

[0213] FIG7 is a schematic flow chart of a wireless communication method 300 according to another embodiment of the present application. As shown in FIG7 , the method 300 includes the following contents:

[0214] S310, after successfully receiving the random access response RAR, the terminal device immediately starts a contention resolution timer;

[0215] S320: Monitor a physical downlink control channel PDCCH while the contention resolution timer is running.

[0216] 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.

[0217] 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.

[0218] 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.

[0219] Optionally, the M is predefined or configured by the network device.

[0220] Optionally, N is predefined or configured by the network device.

[0221] Optionally, the Nth time unit may be the Nth symbol, the Nth time slot, etc., which is not limited in this application.

[0222] In some embodiments, the terminal device initiates random access to a first cell, and the first cell supports blind retransmission scheduling of an initial transmission of Msg3.

[0223] In some embodiments, the terminal device has the ability to monitor the blind retransmission scheduling of the initial transmission of Msg3; and / or,

[0224] The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of Msg3.

[0225] 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.

[0226] In some embodiments, the method 300 further includes:

[0227] After the initial transmission of Msg3 is completed and a first duration has elapsed, starting or restarting the contention resolution timer, wherein the first duration is the round-trip time (RTT) between the terminal device and the network device;

[0228] While the contention resolution timer is running, the PDCCH is monitored, for example, the PDCCH indicating the retransmission of Msg3 scrambled by TC-RNTI is monitored, and whether contention resolution is unsuccessful is determined based on the monitoring result of the PDCCH.

[0229] Optionally, when repeated transmission is not used for the initial transmission of Msg3, the terminal device starts or restarts ra-ContentionResolutionTimer after sending the initial transmission of Msg3 and the first time duration has elapsed.

[0230] 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.

[0231] 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 a UE-gNB RTT.

[0232] 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. Furthermore, after sending the initial transmission of Msg3 and experiencing UE-gNBRTT, it starts or restarts the ra-ContentionResolutionTimer. During the operation of the ra-ContentionResolutionTimer, it monitors the PDCCH indicating the retransmission of Msg3 encrypted by TC-RNTI.

[0233] 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.

[0234] 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.

[0235] FIG9 shows a schematic block diagram of a terminal device 400 according to an embodiment of the present application. As shown in FIG9 , the terminal device 400 includes:

[0236] The processing unit 410 is configured to determine whether contention resolution is unsuccessful based on the start time and / or timeout time of the first contention resolution timer when the first contention resolution timer times out during the random access process.

[0237] In some embodiments, the processing unit 410 is further configured to:

[0238] If the first condition is met, the contention resolution is not considered unsuccessful, wherein the first condition includes one of the following:

[0239] The first contention resolution timer is a contention resolution timer started for the first time during the random access process;

[0240] The first contention resolution timer is started before a first time unit in the random access process, wherein the first time unit is a time unit after the terminal device completes 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;

[0241] 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 completes the initial transmission of message 3 and a first duration has elapsed, and the first duration is equal to the RTT between the terminal device and the network device;

[0242] The first contention resolution timer is started immediately after the terminal device successfully receives the random access response RAR;

[0243] The first contention resolution timer is started immediately after the terminal device completes the initial transmission of message 3.

[0244] In some embodiments, the first condition further includes:

[0245] 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.

[0246] In some embodiments, the first condition further includes:

[0247] The terminal device has the ability to monitor the blind retransmission scheduling of the initial transmission of message 3; and / or,

[0248] The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.

[0249] In some embodiments, the processing unit 410 is further configured to:

[0250] If the second condition is met, the contention resolution is considered unsuccessful, wherein the second condition includes one of the following:

[0251] 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 started at the moment when the terminal device successfully receives the RAR;

[0252] After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of the TC-RNTI-scrambled indication 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;

[0253] 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;

[0254] 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 when the first contention resolution timer expires 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;

[0255] 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 procedure;

[0256] 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 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;

[0257] After the first contention resolution timer is started, the terminal device has not received the PDCCH indicating the retransmission of the TC-RNTI encrypted indication message 3, 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.

[0258] In some embodiments, the second condition further includes:

[0259] The terminal device has the ability to monitor the blind retransmission scheduling of the initial transmission of message 3; and / or,

[0260] The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.

[0261] In some embodiments, the first contention resolution timer is the timer that was last started or restarted by the terminal device.

[0262] In some embodiments, the terminal device is a terminal device in a non-terrestrial network (NTN) cell.

[0263] Alternatively, 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.

[0264] 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 embodiment of the method 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. For the sake of brevity, they will not be repeated here.

[0265] 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:

[0266] The processing unit 510 is configured to start a contention resolution timer immediately after successfully receiving the random access response RAR;

[0267] The communication unit 520 is configured to monitor a physical downlink control channel PDCCH during the running of the contention resolution timer.

[0268] In some embodiments, the processing unit 510 is further configured to:

[0269] At the Mth PDCCH monitoring opportunity after successfully receiving the RAR, start the contention resolution timer, where M is a positive integer; or

[0270] The contention resolution timer is started at the Nth time unit after the RAR is successfully received, where N is a positive integer.

[0271] In some embodiments, the M is predefined or configured by the network device.

[0272] 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 the initial transmission of Message 3.

[0273] In some embodiments, the terminal device has the capability to monitor the blind retransmission scheduling of the initial transmission of message 3; and / or,

[0274] The terminal device has a need to monitor the blind retransmission scheduling of the initial transmission of message 3.

[0275] In some embodiments, the processing unit 510 is further configured to:

[0276] After the initial transmission of message 3 is completed 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;

[0277] The communication unit 520 is further configured to: monitor the PDCCH while the contention resolution timer is running.

[0278] In some embodiments, the terminal device is a terminal device in a non-terrestrial network (NTN) cell.

[0279] Alternatively, 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.

[0280] 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 embodiment of the method 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. For the sake of brevity, they will not be repeated here.

[0281] Figure 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 Figure 11 includes a processor 610, which can call and run a computer program from a memory to implement the method in the embodiment of the present application.

[0282] Optionally, as shown in FIG11 , the communication device 600 may further include a memory 620. The processor 610 may call and execute a computer program from the memory 620 to implement the method in the embodiment of the present application.

[0283] The memory 620 may be a separate device independent of the processor 610 , or may be integrated into the processor 610 .

[0284] Optionally, as shown in FIG11 , 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, to send information or data to other devices, or to receive information or data sent by other devices.

[0285] The transceiver 630 may include a transmitter and a receiver. The transceiver 630 may further include an antenna, and the number of antennas may be one or more.

[0286] Optionally, the communication device 600 may specifically be a network device in an embodiment of the present application, and the communication device 600 may implement the corresponding processes implemented by the network device in each method in the embodiment of the present application. For the sake of brevity, they will not be repeated here.

[0287] Optionally, the communication device 600 may specifically be a mobile terminal / terminal device in 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 in the embodiment of the present application. For the sake of brevity, they will not be repeated here.

[0288] Figure 12 is a schematic structural diagram of a chip according to an embodiment of the present application. The chip 700 shown in Figure 12 includes a processor 710, which can call and run a computer program from a memory to implement the method according to the embodiment of the present application.

[0289] Optionally, as shown in FIG12 , the chip 700 may further include a memory 720 , wherein the processor 710 may call and execute a computer program from the memory 720 to implement the method in the embodiment of the present application.

[0290] The memory 720 may be a separate device independent of the processor 710 , or may be integrated into the processor 710 .

[0291] 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.

[0292] 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.

[0293] 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.

[0294] 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.

[0295] 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.

[0296] 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 .

[0297] 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.

[0298] It should be understood that the processor of the embodiments of the present application may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method embodiment can be completed by hardware integrated logic circuits in the processor or software instructions. The above processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The various methods, steps, and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in the embodiments of the present application can be directly embodied as being executed by a hardware decoding processor, or can be executed by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium mature in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, 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.

[0299] It is understood that the memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may 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 may 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 random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct RAM bus random access memory (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.

[0300] It should be understood that the above-mentioned memories are exemplary but not restrictive. For example, the memories in the embodiments of the present application may also be static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct RAM RAM (DR RAM), etc. In other words, the memories in the embodiments of the present application are intended to include, but are not limited to, these and any other suitable types of memories.

[0301] An embodiment of the present application also provides a computer-readable storage medium for storing a computer program.

[0302] 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.

[0303] 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 will not be repeated here.

[0304] An embodiment of the present application also provides a computer program product, including computer program instructions.

[0305] 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.

[0306] 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 will not be repeated here.

[0307] The embodiment of the present application also provides a computer program.

[0308] 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.

[0309] Optionally, the computer program can be applied to the mobile terminal / terminal device in the embodiments of the present application. When the computer program runs on the 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 will not be repeated here.

[0310] Those skilled 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 beyond the scope of this application.

[0311] Those skilled in the art will 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.

[0312] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, 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.

[0313] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0314] 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.

[0315] 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, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0316] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A wireless communication method, characterized in that: include: When the first contention resolution timer in the random access process times out, the terminal device determines whether the contention resolution is unsuccessful based on the start time and / or timeout time of the first contention resolution timer.

2. The method according to claim 1, characterized in that 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: If a first condition is met, the terminal device does not consider contention resolution 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 during the random access process; The first contention resolution timer is started 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 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 completes the initial transmission of message 3 and a first duration has elapsed, 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.

3. The method according to claim 2, characterized in that The first condition also 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.

4. The method according to claim 2 or 3, characterized in that The first condition also includes: The terminal device has the ability to monitor 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.

5. The method according to any one of claims 1 to 4, characterized in that 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: If 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 TC-RNTI scrambled indication message 3, 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 TC-RNTI-scrambled indication message 3, and the time when the first contention resolution timer expires 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 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 procedure; 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 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 the TC-RNTI encrypted indication message 3, 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.

6. The method according to claim 5, characterized in that The second condition also includes: The terminal device has the ability to monitor 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.

7. The method according to any one of claims 1 to 6, characterized in that The first contention resolution timer is the timer that was most recently started or restarted by the terminal device.

8. The method according to any one of claims 1 to 7, characterized in that The terminal device is a terminal device in a non-terrestrial network NTN cell.

9. A wireless communication method, characterized in that: include: 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.

10. The method according to claim 9, characterized in that After successfully receiving the random access response RAR, the terminal device immediately starts a contention resolution timer, including: 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.

11. The method according to claim 10, characterized in that M is predefined or configured by the network device.

12. The method according to claim 10, characterized in that N is predefined or configured by the network device.

13. The method according to any one of claims 9 to 12, 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.

14. The method according to any one of claims 9 to 13, characterized in that The terminal device has the ability to monitor 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.

15. 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 completed 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.

16. The method according to any one of claims 9 to 15, characterized in that The terminal device is a terminal device in a non-terrestrial network NTN cell.

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

18. The terminal device according to claim 17, characterized in that The processing unit 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 a contention resolution timer started for the first time during the random access process; The first contention resolution timer is started 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 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 completes the initial transmission of message 3 and a first duration has elapsed, 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.

19. The terminal device according to claim 18, characterized in that The first condition also 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.

20. The terminal device according to claim 18 or 19, characterized in that: The first condition also includes: The terminal device has the ability to monitor 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.

21. The terminal device according to any one of claims 17 to 20, characterized in that: The processing unit 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 TC-RNTI scrambled indication message 3, 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 TC-RNTI-scrambled indication message 3, and the time when the first contention resolution timer expires 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 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 procedure; 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 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 the TC-RNTI encrypted indication message 3, 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.

22. The terminal device according to claim 21, characterized in that The second condition also includes: The terminal device has the ability to monitor 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.

23. The terminal device according to any one of claims 17 to 22, characterized in that: The first contention resolution timer is the timer that was most recently started or restarted by the terminal device.

24. The terminal device according to any one of claims 17 to 23, characterized in that: The terminal device is a terminal device in a non-terrestrial network NTN cell.

25. A terminal device, characterized in that: include: a processing unit, configured to start a contention resolution timer immediately after successfully receiving a random access response RAR; The communication unit is configured to monitor a physical downlink control channel (PDCCH) during the operation of the contention resolution timer.

26. The terminal device according to claim 25, characterized in that The processing unit is further configured to: At the Mth PDCCH monitoring opportunity after successfully receiving the RAR, the contention resolution timer is started, 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.

27. The terminal device according to claim 26, characterized in that M is predefined or configured by the network device.

28. The terminal device according to claim 26, characterized in that N is predefined or configured by the network device.

29. The terminal device according to any one of claims 25 to 28, 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.

30. The terminal device according to any one of claims 25 to 29, characterized in that: The terminal device has the ability to monitor 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.

31. The terminal device according to any one of claims 25 to 30, characterized in that: The processing unit is further configured to: After the initial transmission of message 3 is completed 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.

32. The terminal device according to any one of claims 25 to 31, characterized in that: The terminal device is a terminal device in a non-terrestrial network NTN cell.

33. A terminal device, characterized in that: include: A processor and a memory, the memory being used to store a computer program, the processor being used to call and run the computer program stored in the memory to perform the method according to any one of claims 1 to 8, or the method according to any one of claims 9 to 16.

34. A chip, characterized in that: include: A processor, configured to call and execute a computer program from a memory, so that a device equipped with the chip executes the method according to any one of claims 1 to 8, or the method according to any one of claims 9 to 16.

35. A computer-readable storage medium, characterized in that Used to store a computer program, wherein the computer program causes 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.

36. A computer program product, characterized in that The method comprises computer program instructions, which cause 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.

37. A computer program, characterized in that The computer program causes 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.

Images