CN117546588A - Random access method, device, equipment and storage medium - Google Patents

Abstract

The application discloses a random access method, a device, equipment and a storage medium, and relates to the technical field of communication. The method is performed by a terminal device, the method comprising: and stopping the running random access contention resolution timer when receiving a message 3 retransmission instruction, wherein the message 3 retransmission instruction is used for indicating that the message 3 is retransmitted. Based on the scheme provided by the embodiment of the application, the problem that the random access contention resolution timer times out in the period from receiving the indication of the retransmission scheduling of the Msg3 to retransmitting the Msg3 or in the period from transmitting the message 3 to restarting the random access contention resolution timer can be prevented from happening, so that the occurrence of unnecessary contention resolution failure condition is avoided.

Description

Random access method, device, equipment and storage medium Technical Field

The embodiment of the application relates to the technical field of communication, in particular to a random access method, a device, equipment and a storage medium.

Background

In a communication system, a contention-based random access procedure and a non-contention-based random access procedure are supported.

The contention-based random access procedure requires the terminal device to transmit the message 3 (Msg 3) after the terminal device successfully receives the message 2 (Msg 2) as compared to the non-contention-based random access procedure, and the terminal device starts/restarts a timer random access contention resolution timer (ra-contentioresolute) after each transmission of the message 3 and listens to the physical downlink control channel (Physical Downlink Control Channel, PDCCH) during the timer run time to receive the message 4 (Msg 4) to complete the random access contention resolution.

Disclosure of Invention

The embodiment of the application provides a random access method, a device, equipment and a storage medium, which can avoid unnecessary occurrence of a contention resolution failure condition. The technical scheme is as follows:

according to an aspect of embodiments of the present application, there is provided a random access method, which is performed by a terminal device, the method including:

and stopping the running random access contention resolution timer when receiving a message 3 retransmission instruction, wherein the message 3 retransmission instruction is used for indicating that the message 3 is retransmitted.

According to an aspect of embodiments of the present application, there is provided a random access method, the method being performed by a network device, the method comprising:

Transmitting a message 3 retransmission indication to the terminal equipment;

the message 3 retransmission indication is used for indicating to retransmit the message 3, and the terminal equipment stops running random access contention resolution timer under the condition that the message 3 retransmission indication is received.

According to an aspect of embodiments of the present application, there is provided a random access apparatus, including: a timer control module;

the timer control module is configured to stop an running random access contention resolution timer when receiving a message 3 retransmission indication, where the message 3 retransmission indication is used to indicate retransmission of the message 3.

According to an aspect of embodiments of the present application, there is provided a random access apparatus, including: a transmitting module;

the sending module is used for sending a message 3 retransmission instruction to the terminal equipment;

the message 3 retransmission indication is used for indicating to retransmit the message 3, and the terminal equipment stops running random access contention resolution timer under the condition that the message 3 retransmission indication is received.

According to an aspect of embodiments of the present application, there is provided a terminal device including a processor;

The processor is configured to stop an running random access contention resolution timer when receiving a message 3 retransmission indication, where the message 3 retransmission indication is used to indicate retransmission of the message 3.

According to one aspect of embodiments of the present application, there is provided a network device comprising a transceiver;

the transceiver is used for sending a message 3 retransmission instruction to the terminal equipment;

the message 3 retransmission indication is used for indicating to retransmit the message 3, and the terminal equipment stops running random access contention resolution timer under the condition that the message 3 retransmission indication is received.

According to an aspect of the embodiments of the present application, there is provided a computer readable storage medium having stored therein a computer program for execution by a processor to implement the random access method described above.

According to an aspect of the embodiments of the present application, there is provided a chip comprising programmable logic circuits and/or program instructions for implementing the above-described random access method when the chip is running.

According to an aspect of embodiments of the present application, there is provided a computer program product or computer program comprising computer instructions stored in a computer readable storage medium, from which a processor reads and executes the computer instructions to implement the random access method described above.

The technical scheme provided by the embodiment of the application can bring the following beneficial effects:

when receiving the message 3 retransmission instruction, the terminal equipment stops running random access contention resolution timer, so that the problem that the random access contention resolution timer is overtime in the period from receiving the instruction Msg3 retransmission scheduling instruction to retransmitting the Msg3 or the problem that the random access contention resolution timer is overtime in the period from sending the message 3 to restarting the random access contention resolution timer can be prevented, and unnecessary contention resolution failure is avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of a random access procedure provided in an exemplary embodiment of the present application;

fig. 2 is a schematic diagram of a random access procedure provided in an exemplary embodiment of the present application;

FIG. 3 is a schematic diagram of a communication system provided in an exemplary embodiment of the present application;

FIG. 4 is a schematic diagram of a communication system provided in an exemplary embodiment of the present application;

FIG. 5 is a schematic diagram of a communication system provided in an exemplary embodiment of the present application;

fig. 6 is a flowchart of a random access method provided in an exemplary embodiment of the present application;

fig. 7 is a flowchart of a random access method provided in an exemplary embodiment of the present application;

fig. 8 is a schematic diagram of a random access procedure provided in an exemplary embodiment of the present application;

fig. 9 is a schematic diagram of a random access procedure provided in an exemplary embodiment of the present application;

fig. 10 is a block diagram of a random access device provided in an exemplary embodiment of the present application;

fig. 11 is a block diagram of a random access device provided in an exemplary embodiment of the present application;

fig. 12 is a schematic structural diagram of a communication device according to an exemplary embodiment of the present application.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

The network architecture and the service scenario described in the embodiments of the present application are for more clearly describing the technical solution of the embodiments of the present application, and do not constitute a limitation on the technical solution provided in the embodiments of the present application, and those skilled in the art can know that, with the evolution of the network architecture and the appearance of the new service scenario, the technical solution provided in the embodiments of the present application is also applicable to similar technical problems.

Before the technical scheme of the application is introduced, some technical knowledge related to the application is introduced and explained.

Non-terrestrial network (Non-Terrestrial Network, NTN) technology

Currently, the related standards organization is researching NTN technology, which generally provides communication services to terrestrial users by adopting a satellite communication mode. Satellite communications have many unique advantages over terrestrial cellular communication networks. First, satellite communications are not limited by the user region, for example, general land communications cannot cover areas where communication devices cannot be installed, such as oceans, mountains, deserts, etc., or communication coverage is not performed due to rarity of population, while for satellite communications, since one satellite can cover a larger ground, and the satellite can orbit around the earth, theoretically every corner on the earth can be covered by satellite communications. And secondly, satellite communication has great social value. Satellite communication can be covered in remote mountain areas, poor and backward countries or regions with lower cost, so that people in the regions enjoy advanced voice communication and mobile internet technology, and the digital gap between developed regions is reduced, and the development of the regions is promoted. Again, the satellite communication distance is far, and the cost of communication is not obviously increased when the communication distance is increased; and finally, the satellite communication has high stability and is not limited by natural disasters.

Communication satellites are classified into Low Earth Orbit (LEO) satellites, medium Earth Orbit (MEO) satellites, geosynchronous Orbit (Geostationary Earth Orbit, GEO) satellites, high elliptical Orbit (High Elliptical Orbit, HEO) satellites, and the like according to the Orbit heights. LEO and GEO are the main studies at the present stage.

1、LEO

The low orbit satellite has a height ranging from 500km to 1500km and a corresponding orbit period of about 1.5 hours to 2 hours. The signal propagation delay for single hop communications between users is typically less than 20ms. The maximum satellite visibility time is 20 minutes. The signal propagation distance is short, the link loss is less, and the requirement on the transmitting power of the user terminal equipment is not high.

2、GEO

Geosynchronous orbit satellites have an orbit height of 35786km and a period of 24 hours around the earth. The signal propagation delay for single hop communications between users is typically 250ms.

In order to ensure the coverage of the satellite and improve the system capacity of the whole satellite communication system, the satellite adopts multiple beams to cover the ground, and one satellite can form tens or hundreds of beams to cover the ground; a satellite beam may cover a ground area of several tens to hundreds of kilometers in diameter.

Random access procedure

The random access procedure is mainly triggered by the following events:

Establishing a wireless connection upon initial access of the terminal device: the terminal device switches from the RRC IDLE state (rrc_idle state) to the RRC CONNECTED state (rrc_connected state).

Radio resource control (Radio ResourceControl, RRC) connection re-establishment procedure: so that the terminal device reestablishes the radio connection after the radio link failure.

Cell handover: the terminal device needs to establish uplink synchronization with the new cell.

In rrc_connected state, downLink (DL) data arrives, when UL is in out-of-sync state.

In rrc_connected state, upLink (UL) data arrives when UL is in an out-of-sync state or there is no physical UpLink control channel (Physical Uplink Control Channel, PDCCH) resource for transmitting a scheduling request (Scheduling Request, SR).

SR failure.

Synchronous reconfiguration request from RRC.

The terminal device transitions from the RRC INACTIVE state (rrc_inactive state) to the rrc_connected state.

Time alignment is established during Secondary Cell (SCell) addition.

Request other system messages (System Information, SI).

Beam failure recovery.

In a New air interface (NR), two random access modes are mainly supported, namely a contention-based random access mode and a non-contention-based random access mode.

Fig. 1 is a schematic diagram of a random access procedure provided in an exemplary embodiment of the present application. As shown in fig. 1, the contention-based random access procedure is divided into 4 steps, and the non-contention-based random access procedure is divided into 2 steps. The detailed steps are as follows:

(1) The terminal device sends a message 1 (Msg 1) to the network device.

The terminal device selects a physical random access channel (Physical Random Access Channel, PRACH) resource and transmits the selected random access preamble (preamble) on the selected PRACH. The PRACH resources and random access preamble may be specified by the network device if non-contention based random access. The network device may estimate the uplink Timing (Timing) based on the random access preamble and the scheduling (grant) size required for the terminal device to transmit Msg 3.

(2) The network device sends a random access response (Random Access Response, RAR) to the terminal device.

After the terminal device sends Msg1, a Random Access response time window is opened, and a physical downlink control channel (Physical Downlink Control Channel, PDCCH) scrambled by a Random Access radio network temporary identifier (RA-RNTI) is monitored in the Random Access response time window. Wherein, the RA-RNTI is related to PRACH time-frequency resource used by the terminal equipment for transmitting Msg 1.

After the terminal equipment successfully receives the PDCCH scrambled by the RA-RNTI, the terminal equipment can obtain a physical downlink shared channel (Physical Downlink Shared Channel, PDSCH) scheduled by the PDCCH, wherein the physical downlink shared channel comprises an RAR, and the RAR specifically comprises the following information:

the packet header (sub header) of the RAR includes a back-off indication (Backoff Indicator, BI) for indicating a back-off time of retransmission Msg 1;

a random access preamble identification (Random Access Preamble Identity Document, RAPID) in the RAR, the network device responding to the received preamble identification (preamble index);

the load (payload) of the RAR includes a timing advance group (Timing Advance Group, TAG) for adjusting the uplink timing;

uplink scheduling (UL grant) for scheduling Uplink resource indication of Msg 3;

a Temporary Cell-radio network Temporary identity (TC-RNTI) for scrambling the PDCCH (initial access) of message 4 (Msg 4).

If the terminal device receives a PDCCH scrambled by a random access response-radio network temporary identifier (Random Access Response-Radio Network Temporary Identifier, RAR-RNTI) and the RAR includes a preamble identifier (preamble index) transmitted by itself, the terminal device considers that the random access response is successfully received.

For non-contention based random access, after the terminal device successfully receives message 2 (Msg 2), the random access procedure ends. For contention-based random access, after the terminal device successfully receives Msg2, it is further required to continue transmitting Msg3 and receiving Msg4.

(3) The terminal device transmits Msg3 on the network device scheduling resource.

Msg3 is mainly used to inform the network device what event the random access channel (Random Access Channel, RACH) procedure is triggered by. For example, if the initial access random procedure is performed, the Msg3 carries a terminal identifier (UE ID) and an establishment cause (establishment cause); if the connection state terminal is RRC reestablishment, the connection state terminal identification and the establishment cause are carried.

Msg3 supports hybrid automatic repeat request (Hybrid Automatic Repeat Request, HARQ) retransmissions.

(4) The network device sends Msg4 to the terminal device.

After each transmission of Msg3, the terminal device starts or restarts a random access contention resolution timer (ra-contentioresolute), which monitors a Cell-radio network temporary identity (Cell-Radio Network Temporary Identifier, C-RNTI) or TC-RNTI scrambled PDCCH during operation.

Msg4 has two roles, one is for contention conflict resolution and the second is for the network device to transmit RRC configuration messages to the terminal device. The contention resolution is achieved in two ways: one is the PDCCH schedule scrambled with C-RNTI by Msg4 if the terminal device carries a C-RNTI in Msg3. Another is that if the terminal device does not carry a C-RNTI in the Msg3, such as initial access, then the Msg4 is scheduled with a TC-RNTI scrambled PDCCH, and the conflict resolution is that the terminal device receives the PDSCH of the Msg4 by matching the common control channel service data units (Common Control Channel Service Data Unit, CCCH SDU) in the PDSCH.

For the above-mentioned contention-based random access procedure, after each transmission of Msg3, the terminal device will start/restart a random access contention resolution timer (ra-contentioresolute) and monitor the PDCCH during the running time of the timer to receive Msg4. If the terminal equipment does not receive the C-RNTI or the PDCCH scrambled by the TC-RNTI until the random access contention resolution timer is overtime, the random access is considered to be failed, and the terminal equipment can retransmit the Msg1. When the number of times of sending the Msg1 by the terminal equipment reaches a certain threshold, the terminal equipment indicates to a high layer that the random access problem occurs.

In a terrestrial network (Terrestrial Network, TN) system, a random access contention resolution timer starts with the next time symbol after each transmission of Msg3 by the terminal device, the timer duration being configured by the network.

Compared with a TN system, in the NTN system, the Round Trip Time (RTT) of wireless signal transmission between the terminal equipment and the base station is greatly increased, in order to avoid unnecessary PDCCH monitoring of the terminal equipment, a Time offset is introduced on the basis of the original TN for starting a random access contention resolution timer in the NTN system, and based on a relevant NTN standardization conclusion: the time offset is the UE-gNB RTT. Namely: in the NTN system, the terminal device starts or restarts the random access contention resolution timer after finishing transmitting Msg3 each time and going through the RTT duration of the UE-gNB.

Based on the relevant standard protocol, the terminal device will stop the random access contention resolution timer only when Msg4 is received. And in the case of receiving the PDCCH for scheduling the Msg3 retransmission, the random access contention resolution timer is restarted only after the Msg3 retransmission is transmitted. In the NTN system, the starting time of the random access contention resolution timer is delayed by one UE-gNB RTT compared with the TN system, and the original random access contention resolution timer is still continuously operated within the period of time before the random access contention resolution timer is restarted after the terminal equipment transmits the Msg3 retransmission, and the continuous operation time of the timer is at least increased by one UE-gNB RTT compared with the TN system.

It is possible that the originally running random access contention resolution timer has timed out before the moment of restarting the random access contention resolution timer after the terminal device completes the Msg3 retransmission. And based on the relevant standard, if the random access contention resolution timer expires, the terminal device considers that the contention resolution fails, and the terminal device needs to retry the random access. Obviously, in the case of network scheduling of Msg3 retransmissions, the terminal device should continue to monitor the schedule of Msg4 after the Msg3 retransmissions are sent out, but should not consider contention resolution failure early.

For example, as shown in fig. 2, at a time point t1, the terminal device initially transmits Msg3, and starts a random access contention resolution timer at a time point t2 after waiting for the UE-gNB RTT. During the running of the random access contention resolution timer, the terminal device receives a PDCCH at a time point t3, the PDCCH is used for indicating retransmission of the Msg3, the terminal device correspondingly retransmits the Msg3 at a time point t4, and the terminal device restarts the random access contention resolution timer at a time point t5 after waiting for the time of the UE-gNB RTT. And between the time point t4 and the time point t5, the random access contention resolution timer times out, so that the terminal device considers that the contention resolution fails and needs to retry the random access.

In the embodiment of the present application, aiming at the above problem, when the terminal device receives the retransmission indication of the Msg3, the terminal device stops the running random access contention resolution timer, which can prevent the terminal device from timing out of the random access contention resolution timer in the period from receiving the retransmission indication of the Msg3 to retransmitting the Msg3, or from timing out of the random access contention resolution timer in the period from transmitting the retransmission indication of the Msg3 to restarting the random access contention resolution timer, thereby avoiding unnecessary contention resolution failure.

The following describes the technical scheme of the application through several embodiments.

The embodiment of the application can be applied to an NTN system, as shown in fig. 3 and 4, and also can be applied to a TN system, as shown in fig. 5.

Referring to fig. 3, a schematic diagram of an NTN system is shown, in which the communication satellite is a transparent forwarding (transparent payload) satellite. As shown in fig. 3, the NTN system includes: terminal equipment 10, satellites 20, NTN gateway 30, access network equipment 40 and core network equipment 50.

Communication between the terminal device 10 and the access network device 40 may be performed via an air interface, such as the Uu interface. In the architecture shown in fig. 3, the access network device 40 may be deployed on the ground, and uplink and downlink communications between the terminal device 10 and the access network device 40 may be relayed through the satellite 20 and the NTN gateway 30 (typically located on the ground). Taking uplink transmission as an example, the terminal device 10 sends an uplink signal to the satellite 20, the satellite 20 forwards the uplink signal to the NTN gateway 30, the NTN gateway 30 forwards the uplink signal to the access network device 40, and the access network device 40 subsequently sends the uplink signal to the core network device 50. Taking downlink transmission as an example, the downlink signal from the core network device 50 is sent to the access network device 40, the access network device 40 sends the downlink signal to the NTN gateway 30, the NTN gateway 30 forwards the downlink signal to the satellite 20, and the satellite 20 forwards the downlink signal to the terminal device 10.

Referring to fig. 4, a schematic diagram of another NTN system is shown in which the communication satellite is a regenerative forwarding (regenerative payload) satellite. As shown in fig. 4, the NTN system includes: a terminal device 10, a satellite 20, an NTN gateway 30 and a core network device 50.

In the architecture shown in fig. 4, the functionality of the access network device 40 is integrated on the satellite 20, i.e. the satellite 20 is provided with the functionality of the access network device 40. Communication between the terminal device 10 and the satellite 20 may be via an air interface, such as the Uu interface. Communication between the satellite 20 and the NTN gateway 30 (typically located on the ground) may be via a satellite radio interface (Satellite Radio Interface, SRI).

In the architecture shown in fig. 4, taking uplink transmission as an example, the terminal device 10 sends an uplink signal to the satellite 20, the satellite 20 forwards the uplink signal to the NTN gateway 30, and the NTN gateway 30 sends the uplink signal to the core network device 50. Taking downlink transmission as an example, a downlink signal from the core network device 50 is sent to the NTN gateway 30, and the NTN gateway 30 forwards the downlink signal to the satellite 20, and then the satellite 20 forwards the downlink signal to the terminal device 10.

Referring to fig. 5, a schematic diagram of a TN system is shown. As shown in fig. 5, the TN system includes: terminal device 10, access network device 40 and core network device 50.

Communication between the terminal device 10 and the access network device 40 may be performed via an air interface, such as the Uu interface. Taking uplink transmission as an example, the terminal device 10 sends an uplink signal to the access network device 40, and the access network device 40 subsequently sends the uplink signal to the core network device 50. Taking downlink transmission as an example, the downlink signal from the core network device 50 is sent to the access network device 40, and the access network device 40 sends the downlink signal to the terminal device 10.

In the network architecture shown in fig. 3, 4 and 5 described above, the access network device 40 is a device for providing wireless communication services to the terminal device 10. A connection may be established between the access network device 40 and the terminal device 10 so that communication, including interaction of signaling and data, may take place over the connection. The number of access network devices 40 may be plural, and communication between two adjacent access network devices 40 may be performed by wired or wireless means. The terminal device 10 may switch between different access network devices 40, i.e. establish a connection with different access network devices 40.

Taking a cellular communication network as an example, the access network device 40 in the cellular communication network may be a base station. A base station is a device deployed in an access network to provide wireless communication functionality for a terminal device 10. The base stations may include various forms of macro base stations, micro base stations, relay stations, access points, and the like. In systems employing different radio access technologies, the names of base station capable devices may vary, for example in 5G NR systems, called gndeb or gNB. As communication technology evolves, the name "base station" may change. For convenience of description, in the embodiment of the present application, the above-mentioned devices for providing the terminal device 10 with a wireless communication function are collectively referred to as a base station or an access network device.

In addition, the terminal device 10 according to the embodiment of the present application may include various handheld devices, vehicle-mounted devices, wearable devices, computing devices or other processing devices connected to a wireless modem, and various forms of User Equipment (UE), mobile Station (MS), terminal devices (terminal devices), and so on. For convenience of description, in the embodiment of the present application, the above-mentioned devices are collectively referred to as a terminal device. In the embodiments of the present application, some places use "UE" to represent "terminal device". In the embodiments of the present application, the "network device" may be an access network device (e.g., a base station) or a satellite.

In addition, taking a 5G NTN system as an example, a plurality of satellites 20 may be included in the NTN system. One satellite 20 may cover a range of ground areas and provide wireless communication services to the terminal devices 10 on that ground area. In addition, the satellites 20 may orbit the earth, and by deploying multiple satellites 20, communication coverage of different areas of the earth's surface may be achieved.

In addition, in the embodiments of the present application, the terms "network" and "system" are commonly used in combination, but those skilled in the art will understand the meaning. The technical solution described in the embodiments of the present application may be applied to a long term evolution (Long Term Evolution, LTE) system, a 5G system, a subsequent evolution system of a 5G NR system, or other communication systems, which is not limited in this application.

Referring to fig. 6, a flowchart of a random access method according to an embodiment of the present application is shown. The method may comprise the steps of:

step 602: the network device sends a message 3 retransmission indication to the terminal device.

In the embodiment of the present application, the terminal device is performing a random access procedure, and the random access procedure is a contention-based random access procedure, which is shown in fig. 1 (a), and will not be described herein.

In the random access process based on competition, after the terminal equipment successfully receives the message 2, the message 3 is sent on the resource scheduled by the network equipment, and the message 3 is information for carrying out competition resolution in the random access process. The information carried in message 3 includes, for example, at least one of the following: terminal identification (UE ID), connection state terminal identification, establishment cause (establishment cause).

In order to guarantee the transmission reliability of message 3, message 3 supports HARQ retransmission. Wherein the message 3 retransmission indication is used for indicating that the message 3 is retransmitted. Illustratively, in the event that the network device does not successfully receive message 3 sent by the terminal device, the network device sends a message 3 retransmission indication to the terminal device. Illustratively, in the event that the network device does not successfully parse message 3 sent by the terminal device, the network device sends a message 3 retransmission indication to the terminal device.

It will be appreciated that before step 602, the terminal device has sent message 3 to the network device, which message 3 may be either an initial transmitted message 3 or a retransmitted message 3. That is, the message 3 retransmission indication is used to instruct the terminal device to retransmit the message 3 that was originally transmitted, or the message 3 retransmission indication is used to instruct the terminal device to retransmit the retransmitted message 3 again.

Step 604: the terminal device receives the message 3 retransmission indication.

The terminal equipment receives the message 3 retransmission indication issued by the network equipment.

Step 606: the terminal device stops the running random access contention resolution timer.

Upon receiving the message 3 retransmission indication, the terminal device stops the running random access contention resolution timer (ra-contentionresolution timer).

The random access contention resolution timer is a timer operated by the terminal device, and during the operation of the timer, the terminal device monitors the PDCCH to receive the message 4 sent by the network device. The random access contention resolution timer is started after the terminal device transmits the message 3, and is thus always in an operating state. If the timer runs out, the terminal device considers that the contention resolution fails and needs to retry random access.

In this embodiment, before step 602, the terminal device sends a message 3, and then starts a random access contention resolution timer, which is then in an operating state. Illustratively, in a TN system, before step 602, the terminal device sends message 3 and starts a random access contention resolution timer in the first symbol (symbol) that follows. Illustratively, in the NTN system, before step 602, the terminal device sends message 3 and starts a random access contention resolution timer for the first symbol after a terminal device-next generation base station round trip transmission time (UE-gNB RTT)/terminal device-evolved base station round trip transmission time (UE-eNB RTT) duration. After receiving the message 3 retransmission indication, the terminal device stops the running random access contention resolution timer if the random access contention resolution timer is still in an operating state.

It can be understood that, because the terminal device stops the running random access contention resolution timer after receiving the message 3 retransmission indication, the random access contention resolution timer will not timeout during the time period from when the terminal device receives the message 3 retransmission indication to when the terminal device restarts the random access contention resolution timer, or during the time period from when the terminal device receives the message 3 retransmission indication to when the terminal device retransmits the message 3, and the terminal device considers that the contention resolution fails, and needs to retry random access.

In summary, according to the technical solution provided in this embodiment, when the terminal device receives the retransmission indication of the message 3, the running random access contention resolution timer is stopped, so that the problem that the random access contention resolution timer times out during the period from receiving the retransmission scheduling indication of the indication Msg3 to retransmitting the Msg3, or during the period from sending the message 3 to restarting the random access contention resolution timer, can be prevented, thereby avoiding the occurrence of unnecessary contention resolution failure.

In the exemplary embodiment, since the network device schedules the terminal device to perform the message 3 retransmission by the message 3 retransmission indication, the terminal device should send the message 3 retransmission after receiving the message 3 retransmission indication, and restart the random access contention resolution timer to continue listening to the scheduling of the message 4.

Referring to fig. 7, a flowchart of a random access method according to an embodiment of the present application is shown. The method may comprise the steps of:

step 702: the terminal device sends a message 3.

The message 3 is illustratively a message 3 originally transmitted by the terminal device, or the message 3 is a message 3 retransmitted by the terminal device.

Step 704: the network device receives message 3.

The network device receives the message 3 sent by the terminal device. The message 3 is illustratively a message 3 originally transmitted by the terminal device, or the message 3 is a message 3 retransmitted by the terminal device.

Step 706: the terminal device starts a random access contention resolution timer.

Since the terminal device transmits the message 3 in step 702, the terminal device needs to start a random access contention resolution timer, during which the PDCCH is monitored to receive the message 4 transmitted by the network device.

In one possible implementation, where the method is applied to an NTN system, step 706 includes:

after the transmission of message 3, the terminal device starts a random access contention resolution timer in the first time domain unit after the second time offset.

The second time offset refers to a time offset value between a time point when the message 3 is transmitted and a time point when the random access contention resolution timer is started.

Optionally, the second time offset includes at least one of: UE-gNB RTT, UE-eNB RTT. It can be appreciated that the second time offset is an RTT value between the terminal device and the network device in the NTN system, and is not limited to the UE-gNB RTT and the UE-eNB RTT as described above as the communication system evolves.

Optionally, the time domain unit includes at least one of: frames, subframes, slots, and symbols. Illustratively, after the message 3 is sent, the terminal device starts a random access contention resolution timer on the first symbol after the second time offset.

In one possible implementation, where the method is applied to a TN system, step 706 includes:

the terminal device starts a random access contention resolution timer in the first time domain unit after the transmission of message 3.

Optionally, the time domain unit includes at least one of: frames, subframes, slots, and symbols. Illustratively, the terminal device starts a random access contention resolution timer on the first symbol after the message 3 is sent.

In addition, the embodiment of the present application does not limit the implementation sequence of step 704 and step 706. Illustratively, in the NTN system, step 704 is performed first, the network device receives the message 3 first, then step 706 is performed, and the terminal device restarts the random access contention resolution timer. Illustratively, in the TN system, step 706 is performed first, the terminal device starts a random access contention resolution timer first, step 704 is performed, and the network device receives the message 3 again.

Step 708: the network device sends a message 3 retransmission indication to the terminal device.

Optionally, the message 3 retransmission indication is carried in the PDCCH.

Optionally, the PDCCH is scrambled by TC-RNTI. That is, the network device schedules the terminal device to retransmit the message 3 through the TC-RNTI scrambled PDCCH.

Step 710: the terminal device receives the message 3 retransmission indication.

The terminal equipment receives the message 3 retransmission indication issued by the network equipment. Optionally, the message 3 retransmission indication is carried in the PDCCH. Optionally, the PDCCH is scrambled by TC-RNTI.

Step 712: the terminal device stops the running random access contention resolution timer.

Upon receiving the message 3 retransmission indication, the terminal device stops starting the running random access contention resolution timer in step 706. It can be appreciated that since the terminal device stops the running random access contention resolution timer, the terminal device does not have to continue PDCCH monitoring.

Step 714: the terminal device sends a retransmitted message 3.

For example, since the network device schedules the terminal device to perform Msg3 retransmission through the message 3 retransmission indication, the terminal device transmits Msg3 retransmission on the time-frequency domain resource scheduled by the message 3 retransmission indication after receiving the message 3 retransmission indication.

Step 716: the network device receives the retransmitted message 3.

The network device receives the message 3 retransmitted by the terminal device.

Step 718: the terminal device restarts the random access contention resolution timer.

Since the terminal device transmitted the retransmitted message 3 in step 714, the terminal device needs to restart the random access contention resolution timer, and during the operation of the restarted random access contention resolution timer, it resumes listening to the PDCCH to receive the message 4 transmitted by the network device.

In the embodiment of the application, the method is applicable to an NTN system; alternatively, the provided method is applicable to NTN systems and TN systems. That is, the operation of stopping the running random access contention resolution timer is only applicable to the NTN system after receiving the message 3 retransmission indication, or is applicable to both the NTN system and the TN system after receiving the message 3 retransmission indication.

The NTN system refers to a communication system that provides services to the ground user by using a satellite communication manner, as shown in fig. 3 and fig. 4, and the TN system refers to a communication system that provides services to the ground user by not using a satellite communication manner, as shown in fig. 5, which is not described herein.

In one possible implementation, where the method is applied to an NTN system, step 718 includes:

after sending the retransmitted message 3, the terminal device restarts the random access contention resolution timer in the first time domain unit after the first time offset.

Wherein the first time offset refers to a time offset value between a time point when the message 3 is retransmitted and a time point when the random access contention resolution timer is restarted. Optionally, the first time offset is the same as the second time offset, or the first time offset is different from the second time offset.

Optionally, the first time offset includes at least one of: UE-gNB RTT, UE-eNB RTT. It can be appreciated that the first time offset is an RTT value between the terminal device and the network device in the NTN system, and is not limited to the UE-gNB RTT and the UE-eNB RTT as described above as the communication system evolves.

Optionally, the time domain unit includes at least one of: frames, subframes, slots, and symbols. Illustratively, after retransmitting message 3, the terminal device restarts the random access contention resolution timer at the first symbol after the first time offset.

In one possible implementation, where the method is applied to a TN system, step 718 includes:

the terminal device restarts the random access contention resolution timer in the first time domain unit after the retransmission message 3 is transmitted.

Optionally, the time domain unit includes at least one of: frames, subframes, slots, and symbols. Illustratively, the terminal device restarts the random access contention resolution timer the first symbol after retransmitting message 3.

In addition, the embodiment of the present application does not limit the implementation sequence of step 716 and step 7118. Illustratively, in the NTN system, step 716 is performed first, the network device receives the retransmitted message 3 first, then step 718 is performed, and the terminal device restarts the random access contention resolution timer. Illustratively, in the TN system, step 718 is performed first, the terminal device restarts the random access contention resolution timer first, step 716 is performed, and the network device receives the retransmitted message 3.

In summary, according to the technical solution provided in this embodiment, when the terminal device receives the retransmission indication of the message 3, the running random access contention resolution timer is stopped, so that the problem that the random access contention resolution timer times out during the period from receiving the retransmission scheduling indication of the indication Msg3 to retransmitting the Msg3, or during the period from sending the message 3 to restarting the random access contention resolution timer, can be prevented, thereby avoiding the occurrence of unnecessary contention resolution failure.

Meanwhile, according to the technical scheme provided by the embodiment, after receiving the retransmission instruction of the message 3, the terminal equipment retransmits the transmitted message 3, and restarts the random access contention resolution timer to continue monitoring the scheduling of the message 4, so that the continuous execution of the random access process is ensured.

Meanwhile, in the technical scheme provided in this embodiment, since the network device will not send the schedule of the message 4 until the terminal device restarts the random access contention resolution timer at the time point when the terminal device receives the retransmission indication of the message 3, the terminal device stops the running random access contention resolution timer when receiving the retransmission indication of the message 3, and the terminal device will not perform unnecessary PDCCH monitoring, thereby achieving the effect of saving power.

The random access method provided in the present application above is exemplarily described with reference to fig. 8.

As shown in fig. 8, in the NTN system, at a time point t1, the terminal device initially transmits Msg3, and after waiting for the time of the UE-gNB RTT, starts a random access contention resolution timer at a time point t 2.

During the running of the random access contention resolution timer, the terminal device receives a PDCCH scrambled by the TC-RNTI at a time point t3, the PDCCH being used for indicating retransmission of Msg3, and stops the running random access contention resolution timer at the time point t 3.

At the time point t4, the terminal equipment sends retransmission of the Msg3, waits for the RTT of the UE-gNB after the retransmission of the Msg3 is sent, and restarts the random access contention resolution timer at the time point t 5.

As shown in fig. 8, at the time point from t3 to t5, since the random access contention resolution timer corresponding to the previous Msg3 has stopped running, the problem of timeout of the random access contention resolution timer does not occur, so that unnecessary contention resolution failure is avoided, and unnecessary PDCCH monitoring is not performed, thereby achieving the effect of saving power.

The random access method provided in the present application above is exemplarily described with reference to fig. 9.

As shown in fig. 9, in the TN system, at a time point t1, the terminal device initially transmits Msg3, and then starts a random access contention resolution timer.

During the running of the random access contention resolution timer, the terminal device receives a PDCCH scrambled by the TC-RNTI at a time point t2, the PDCCH being used for indicating retransmission of Msg3, and stops the running random access contention resolution timer at the time point t 2.

At the time point t3, the terminal device sends retransmission of the Msg3, and immediately restarts the random access contention resolution timer after the retransmission of the Msg3 is sent.

As shown in fig. 9, at the time point from t2 to t3, since the random access contention resolution timer corresponding to the previous Msg3 has stopped running, the problem of timeout of the random access contention resolution timer does not occur, so that unnecessary contention resolution failure is avoided, and unnecessary PDCCH monitoring is not performed, thereby achieving the effect of saving power.

It will be appreciated that the above method embodiments may be implemented alone or in combination, and are not limited in this application.

The following are device embodiments of the present application, which may be used to perform method embodiments of the present application. For details not disclosed in the device embodiments of the present application, please refer to the method embodiments of the present application.

Referring to fig. 10, a block diagram of a random access device according to an embodiment of the present application is shown. The device has the function of realizing the method example of the terminal equipment side, and the function can be realized by hardware or can be realized by executing corresponding software by hardware. The device may be the terminal device described above, or may be provided in the terminal device. As shown in fig. 10, the apparatus 1000 may include: a timer control module 1002;

The timer control module 1002 is configured to stop the running random access contention resolution timer when receiving a message 3 retransmission indication, where the message 3 retransmission indication is used to indicate retransmission of the message 3.

In an alternative embodiment, the apparatus is adapted for use in an NTN system;

or alternatively, the first and second heat exchangers may be,

the device is suitable for the NTN system and the TN system.

In an alternative embodiment, the apparatus further comprises: a transmitting module;

the sending module is configured to send the retransmitted message 3;

the timer control module 1002 is configured to restart the random access contention resolution timer.

In an alternative embodiment, in case the apparatus is applied to the NTN system;

the timer control module 1002 is configured to restart the random access contention resolution timer after the retransmission of the message 3 is sent, in a first time domain unit after a first time offset.

In an alternative embodiment, the first time offset includes at least one of: UE-gNB RTT, UE-eNB RTT.

In an alternative embodiment, in the case where the apparatus is applied to the TN system;

The timer control module 1002 is configured to restart the random access contention resolution timer in a first time domain unit after the retransmission of the message 3 is sent.

In an alternative embodiment, the apparatus further comprises: a transmitting module;

the sending module is used for sending the message 3;

the timer control module 1002 is configured to start the random access contention resolution timer.

In an alternative embodiment, in the case where the apparatus is applied to an NTN system;

the timer control module 1002 is configured to start the random access contention resolution timer after the message 3 is sent, in a first time domain unit after a second time offset.

In an alternative embodiment, the second time offset is the same as the first time offset;

or alternatively, the first and second heat exchangers may be,

the second time offset is different from the first time offset, which is the time offset that the device experiences to restart the random access contention resolution timer after having sent the message 3 of retransmission.

In an alternative embodiment, the second time offset includes at least one of:

UE-gNB RTT、UE-eNB RTT。

In an alternative embodiment, in the case where the apparatus is applied to a TN system;

the timer control module 1002 is configured to start the random access contention resolution timer in a first time domain unit after the message 3 is sent.

In an alternative embodiment, the time domain unit includes at least one of: frames, subframes, slots, and symbols.

In an alternative embodiment, the message 3 retransmission indication is carried in the PDCCH.

In an alternative embodiment, the PDCCH is scrambled by a TC-RNTI.

Referring to fig. 11, a block diagram of a random access device according to an embodiment of the present application is shown. The device has the function of realizing the method example of the network equipment side, and the function can be realized by hardware or can be realized by executing corresponding software by hardware. The apparatus may be the network device described above, or may be provided in the network device. As shown in fig. 11, the apparatus 1100 may include: a transmitting module 1102;

the sending module 1102 is configured to send a message 3 retransmission indication to a terminal device;

the message 3 retransmission indication is used for indicating to retransmit the message 3, and the terminal equipment stops running random access contention resolution timer under the condition that the message 3 retransmission indication is received.

In an alternative embodiment, the apparatus is adapted for use in an NTN system;

or alternatively, the first and second heat exchangers may be,

the device is suitable for the NTN system and the TN system.

In an alternative embodiment, the apparatus further comprises: a receiving module;

the receiving module is configured to receive the retransmitted message 3 after sending the retransmission indication of the message 3 to the terminal device.

In an alternative embodiment, the apparatus further comprises: a receiving module;

the receiving module is configured to receive the message 3 before sending the message 3 retransmission indication to the terminal device.

In an alternative embodiment, the message 3 retransmission indication is carried in the PDCCH.

In an alternative embodiment, the PDCCH is scrambled by a TC-RNTI.

It should be noted that, when the apparatus provided in the foregoing embodiment performs the functions thereof, only the division of the respective functional modules is used as an example, in practical application, the foregoing functional allocation may be performed by different functional modules according to actual needs, that is, the content structure of the device is divided into different functional modules, so as to perform all or part of the functions described above.

The specific manner in which the various modules perform the operations in the apparatus of the above embodiments have been described in detail in connection with the embodiments of the method, and will not be described in detail herein.

Referring to fig. 12, a schematic structural diagram of a communication device (terminal device or network device) according to an embodiment of the present application is shown. The communication device may include: a processor 1201, a receiver 1202, a transmitter 1203, a memory 1204, and a bus 1205.

The processor 1201 includes one or more processing cores, and the processor 1201 executes various functional applications and performs random access by running software programs and modules.

The receiver 1202 and the transmitter 1203 may be implemented as one transceiver 1206, and the transceiver 1206 may be a communication chip.

The memory 1204 is connected to the processor 1201 by a bus 1205.

The memory 1204 may be used for storing a computer program, and the processor 1201 is used for executing the computer program to implement the steps performed by the terminal device in the above-described method embodiment.

Further, the memory 1204 may be implemented by any type or combination of volatile or nonvolatile memory devices including, but not limited to: random-Access Memory (RAM) and Read-Only Memory (ROM), erasable programmable Read-Only Memory (EPROM), electrically erasable programmable Read-Only Memory (Electrically Erasable Programmable Read-Only Memory, EEPROM), flash Memory or other solid state Memory technology, read-Only optical disk (Compact Disc Read-Only Memory, CD-ROM), high density digital video disk (Digital Video Disc, DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices.

When the communication device is implemented as a terminal device, the processor 1201 and the transceiver 1206 in the embodiments of the present application may perform the steps performed by the terminal device in any of the methods shown in fig. 6 to 7, which are not described herein.

In one possible implementation, when the communication device is implemented as a terminal device,

the processor 1201 is configured to stop the running random access contention resolution timer when receiving a message 3 retransmission indication, where the message 3 retransmission indication is used to indicate that the message 3 is retransmitted.

Optionally, the method is applicable to NTN systems;

or alternatively, the first and second heat exchangers may be,

the method is applicable to the NTN system and the TN system.

Optionally, the transceiver 1206 is configured to send the retransmitted message 3 after receiving the message 3 retransmission indication;

the processor 1201 is configured to restart the random access contention resolution timer.

Optionally, in case the method is applied to the NTN system, the processor 1201 is configured to restart the random access contention resolution timer in a first time domain unit after the retransmission of the message 3 is sent.

Optionally, the first time offset includes at least one of:

UE-gNB RTT、UE-eNB RTT。

optionally, in case the method is applied to the TN system, the processor 1201 is configured to restart the random access contention resolution timer in a first time domain unit after the message 3 is sent.

Optionally, the transceiver 1206 is configured to send the message 3 before receiving the message 3 retransmission indication;

the processor 1201 is configured to start the random access contention resolution timer.

Optionally, in case the method is applied to an NTN system, the processor 1201 is configured to start the random access contention resolution timer after the transmission of the message 3 by a first time domain unit after a second time offset.

Optionally, the second time offset is the same as the first time offset;

or alternatively, the first and second heat exchangers may be,

the second time offset is different from the first time offset, and the first time offset is the time offset that the terminal device has restarted the random access contention resolution timer after sending the retransmitted message 3.

Optionally, the second time offset includes at least one of:

UE-gNB RTT、UE-eNB RTT。

Optionally, in case the method is applied to a TN system, the processor 1201 is configured to start the random access contention resolution timer in a first time domain unit after the message 3 is sent.

Optionally, the time domain unit includes at least one of: frames, subframes, slots, and symbols.

Optionally, the message 3 retransmission indication is carried in a PDCCH.

Optionally, the PDCCH is scrambled by TC-RNTI.

When the communication device is implemented as a network device, the transceiver 1206 in the embodiments of the present application may perform the steps performed by the network device in any of the methods shown in fig. 6 to 7, which are not described herein.

In one possible implementation, when the communication device is implemented as a network device,

the transceiver 1206 is configured to send a message 3 retransmission indication to a terminal device;

the message 3 retransmission indication is used for indicating to retransmit the message 3, and the terminal equipment stops running random access contention resolution timer under the condition that the message 3 retransmission indication is received.

Optionally, the method is applicable to NTN systems;

or alternatively, the first and second heat exchangers may be,

the method is applicable to the NTN system and the TN system.

Optionally, the transceiver 1206 is configured to receive the retransmitted message 3 after sending the message 3 retransmission indication to the terminal device.

Optionally, the transceiver 1206 is configured to receive the message 3 before sending the message 3 retransmission indication to the terminal device.

Optionally, the message 3 retransmission indication is carried in a PDCCH.

Optionally, the PDCCH is scrambled by TC-RNTI.

The embodiment of the application also provides a computer readable storage medium, wherein the storage medium stores a computer program, and the computer program is used for being executed by a processor of a terminal device to realize the random access method of the terminal device side, or is used for being executed by a processor of a network device to realize the random access method of the network device side.

Alternatively, the computer-readable storage medium may include: read-Only Memory (ROM), random-Access Memory (RAM), solid state disk (Solid State Drives, SSD), or optical disk, etc. The random access memory may include resistive random access memory (Resistance Random Access Memory, reRAM) and dynamic random access memory (Dynamic Random Access Memory, DRAM), among others.

The embodiment of the application also provides a chip, which comprises a programmable logic circuit and/or program instructions and is used for realizing the random access method of the terminal equipment side when the chip runs on the terminal equipment or the random access method of the network equipment side when the chip runs on the network equipment.

The embodiment of the application also provides a computer program product or a computer program, which comprises computer instructions, wherein the computer instructions are stored in a computer readable storage medium, a processor of the terminal device reads and executes the computer instructions from the computer readable storage medium to realize the random access method of the terminal device side, or a processor of the network device reads and executes the computer instructions from the computer readable storage medium to realize the random access method of the network device side.

It should be understood that, in the embodiments of the present application, the "indication" may be a direct indication, an indirect indication, or an indication having an association relationship. For example, a indicates B, which may mean that a indicates B directly, e.g., B may be obtained by a; it may also indicate that a indicates B indirectly, e.g. a indicates C, B may be obtained by C; it may also be indicated that there is an association between a and B.

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

References herein to "a plurality" means two or more. "and/or", describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate: a exists alone, A and B exist together, and B exists alone. The character "/" generally indicates that the context-dependent object is an "or" relationship.

In addition, the step numbers described herein are merely exemplary of one possible execution sequence among steps, and in some other embodiments, the steps may be executed out of the order of numbers, such as two differently numbered steps being executed simultaneously, or two differently numbered steps being executed in an order opposite to that shown, which is not limited by the embodiments of the present application.

Those skilled in the art will appreciate that in one or more of the examples described above, the functions described in the embodiments of the present application may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, these functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.

The foregoing description of the exemplary embodiments of the present application is not intended to limit the invention to the particular embodiments disclosed, but on the contrary, the intention is to cover all modifications, equivalents, alternatives, and alternatives falling within the spirit and scope of the invention.

Claims (45)

1. A random access method, the method being performed by a terminal device, the method comprising:

   and stopping the running random access contention resolution timer when receiving a message 3 retransmission instruction, wherein the message 3 retransmission instruction is used for indicating that the message 3 is retransmitted.
2. The method of claim 1, wherein the step of determining the position of the substrate comprises,

   the method is suitable for a non-ground communication network NTN system;

   or alternatively, the first and second heat exchangers may be,

   the method is suitable for the NTN system and the ground communication network TN system.
3. The method according to claim 1 or 2, characterized in that after receiving the message 3 retransmission indication, the method further comprises:

   transmitting the retransmitted message 3;

   restarting the random access contention resolution timer.
4. A method according to claim 3, wherein, in the case where the method is applied to an NTN system, the restarting the random access contention resolution timer comprises:

   After the retransmission of the message 3 is sent, the random access contention resolution timer is restarted in the first time domain unit after a first time offset.
5. The method of claim 4, wherein the first time offset comprises at least one of:

   terminal equipment-next generation base station round trip transmission time UE-gNB RTT, terminal equipment-evolved base station round trip transmission time UE-eNB RTT.
6. A method according to claim 3, wherein, in case the method is applied to a TN system, the restarting the random access contention resolution timer comprises:

   restarting the random access contention resolution timer in the first time domain unit after the retransmission of the message 3 is transmitted.
7. The method according to any of claims 1 to 6, characterized in that before receiving the message 3 retransmission indication, the method further comprises:

   sending the message 3;

   and starting the random access contention resolution timer.
8. The method according to claim 7, wherein in case the method is applied to an NTN system, the starting the random access contention resolution timer comprises:

   After the message 3 is sent, the random access contention resolution timer is started in the first time domain unit after the second time offset.
9. The method of claim 8, wherein the step of determining the position of the first electrode is performed,

   the second time offset is the same as the first time offset;

   or alternatively, the first and second heat exchangers may be,

   the second time offset is different from the first time offset, and the first time offset is the time offset that the terminal device has restarted the random access contention resolution timer after sending the retransmitted message 3.
10. The method of claim 8, wherein the second time offset comprises at least one of:

    UE-gNB RTT、UE-eNB RTT。
11. the method according to claim 7, wherein in case the method is applied to a TN system, the starting the random access contention resolution timer comprises:

    starting the random access contention resolution timer in the first time domain unit after the transmission of the message 3.
12. The method according to claim 4 or 6 or 8 or 11, wherein the time domain unit comprises at least one of:

    frames, subframes, slots, and symbols.
13. The method according to any one of claims 1 to 12, wherein,

    the message 3 retransmission indication is carried in a physical downlink control channel PDCCH.
14. The method of claim 13, wherein the step of determining the position of the probe is performed,

    the PDCCH is scrambled by a temporary cell-radio network temporary identity TC-RNTI.
15. A random access method, the method performed by a network device, the method comprising:

    transmitting a message 3 retransmission indication to the terminal equipment;

    the message 3 retransmission indication is used for indicating to retransmit the message 3, and the terminal equipment stops running random access contention resolution timer under the condition that the message 3 retransmission indication is received.
16. The method of claim 15, wherein the step of determining the position of the probe is performed,

    the method is suitable for a non-ground communication network NTN system;

    or alternatively, the first and second heat exchangers may be,

    the method is suitable for the NTN system and the ground communication network TN system.
17. The method according to claim 15 or 16, characterized in that after said sending of the message 3 retransmission indication to the terminal device, the method further comprises:

    and receiving the retransmitted message 3.
18. The method according to any of the claims 15 to 17, characterized in that before said sending of the message 3 retransmission indication to the terminal device, the method further comprises:

    The message 3 is received.
19. The method according to any one of claims 15 to 18, wherein,

    the message 3 retransmission indication is carried in a physical downlink control channel PDCCH.
20. The method of claim 19, wherein the step of determining the position of the probe comprises,

    the PDCCH is scrambled by a temporary cell-radio network temporary identity TC-RNTI.
21. A random access device, the device comprising: a timer control module;

    the timer control module is configured to stop an running random access contention resolution timer when receiving a message 3 retransmission indication, where the message 3 retransmission indication is used to indicate retransmission of the message 3.
22. The apparatus of claim 21, wherein the device comprises a plurality of sensors,

    the device is suitable for a non-ground communication network NTN system;

    or alternatively, the first and second heat exchangers may be,

    the device is suitable for the NTN system and the ground communication network TN system.
23. The apparatus according to claim 21 or 22, characterized in that the apparatus further comprises: a transmitting module;

    the sending module is configured to send the retransmitted message 3;

    the timer control module is configured to restart the random access contention resolution timer.
24. The apparatus of claim 23, wherein in the case that the apparatus is applied to an NTN system;

    The timer control module is configured to restart the random access contention resolution timer after the retransmission of the message 3 is sent, in a first time domain unit after a first time offset.
25. The apparatus of claim 24, wherein the first time offset comprises at least one of:

    terminal equipment-next generation base station round trip transmission time UE-gNB RTT, terminal equipment-evolved base station round trip transmission time UE-eNB RTT.
26. The apparatus according to claim 23, wherein in case the apparatus is applied to a TN system;

    the timer control module is configured to restart the random access contention resolution timer in a first time domain unit after the retransmission of the message 3 is sent.
27. The apparatus according to any one of claims 21 to 26, further comprising: a transmitting module;

    the sending module is used for sending the message 3;

    the timer control module is configured to start the random access contention resolution timer.
28. The apparatus of claim 27, wherein in the case where the apparatus is applied to an NTN system;

    The timer control module is configured to start the random access contention resolution timer after the message 3 is sent and after a first time domain unit after a second time offset.
29. The apparatus of claim 28, wherein the device comprises a plurality of sensors,

    the second time offset is the same as the first time offset;

    or alternatively, the first and second heat exchangers may be,

    the second time offset is different from the first time offset, which is the time offset that the device experiences to restart the random access contention resolution timer after having sent the message 3 of retransmission.
30. The apparatus of claim 28, wherein the second time offset comprises at least one of:

    UE-gNB RTT、UE-eNB RTT。
31. the apparatus according to claim 27, wherein in case the apparatus is applied to a TN system;

    the timer control module is configured to start the random access contention resolution timer in a first time domain unit after the message 3 is sent.
32. The apparatus of claim 24 or 26 or 28 or 31, wherein the time domain unit comprises at least one of:

    frames, subframes, slots, and symbols.
33. The apparatus according to any one of claims 21 to 32, wherein,

    the message 3 retransmission indication is carried in a physical downlink control channel PDCCH.
34. The apparatus of claim 33, wherein the device comprises a plurality of sensors,

    the PDCCH is scrambled by a temporary cell-radio network temporary identity TC-RNTI.
35. A random access device, the device comprising: a transmitting module;

    the sending module is used for sending a message 3 retransmission instruction to the terminal equipment;

    the message 3 retransmission indication is used for indicating to retransmit the message 3, and the terminal equipment stops running random access contention resolution timer under the condition that the message 3 retransmission indication is received.
36. The apparatus of claim 35, wherein the device comprises a plurality of sensors,

    the device is suitable for a non-ground communication network NTN system;

    or alternatively, the first and second heat exchangers may be,

    the device is suitable for the NTN system and the ground communication network TN system.
37. The apparatus according to claim 35 or 36, characterized in that the apparatus further comprises: a receiving module;

    the receiving module is configured to receive the retransmitted message 3 after sending the retransmission indication of the message 3 to the terminal device.
38. The apparatus according to any one of claims 35 to 37, further comprising: a receiving module;

    the receiving module is configured to receive the message 3 before sending the message 3 retransmission indication to the terminal device.
39. The apparatus according to any one of claims 35 to 38, wherein,

    the message 3 retransmission indication is carried in a physical downlink control channel PDCCH.
40. The apparatus of claim 39, wherein the device comprises,

    the PDCCH is scrambled by a temporary cell-radio network temporary identity TC-RNTI.
41. A terminal device, characterized in that the terminal device comprises a processor;

    the processor is configured to stop an running random access contention resolution timer when receiving a message 3 retransmission indication, where the message 3 retransmission indication is used to indicate retransmission of the message 3.
42. A network device, the network device comprising a transceiver;

    the transceiver is used for sending a message 3 retransmission instruction to the terminal equipment;

    the message 3 retransmission indication is used for indicating to retransmit the message 3, and the terminal equipment stops running random access contention resolution timer under the condition that the message 3 retransmission indication is received.
43. A computer readable storage medium, characterized in that the storage medium has stored therein a computer program for execution by a processor for implementing the random access method according to any of claims 1 to 20.
44. A chip comprising programmable logic circuits and/or program instructions for implementing the random access method of any one of claims 1 to 20 when the chip is operating.
45. A computer program product or computer program comprising computer instructions stored in a computer readable storage medium, from which a processor reads and executes the computer instructions to implement the random access method according to any of claims 1 to 20.