CN112806063A

CN112806063A - Method and device for cell switching

Info

Publication number: CN112806063A
Application number: CN201980066159.4A
Authority: CN
Inventors: 卢前溪; 尤心
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2019-04-30
Filing date: 2019-04-30
Publication date: 2021-05-14
Anticipated expiration: 2039-04-30
Also published as: CN112806063B; WO2020220309A1

Abstract

The application provides a method and equipment for cell switching, which can reduce signaling overhead in the switching process of terminal equipment. The method comprises the following steps: the terminal equipment acquires first information from a system message, wherein the first information is used for the terminal equipment to carry out cell switching.

Description

Method and device for cell switching

Technical Field

The present application relates to the field of communications, and more particularly, to a method and apparatus for cell handover.

Background

A New Radio (NR) system supports cell handover, for example, when a terminal device moves from one cell to another cell, or due to reasons such as adjustment of wireless communication traffic load, activation of operation maintenance, and device failure, in order to ensure communication continuity and service quality, a communication link between the terminal device and a source base station needs to be transferred to a target base station, i.e., a handover procedure is performed.

For a terminal device moving at a high speed, the terminal device needs to perform cell switching frequently. In some scenarios, the motion trajectory of the terminal device is determined, such as a high-speed rail scenario, in which case, the source base station may send the configuration information of the target cell to the terminal device in advance, so that the terminal device can perform handover using the configuration information of the target cell when performing cell handover. However, how to instruct the terminal device to perform cell handover by the source base station is an urgent problem to be solved at present.

Disclosure of Invention

The application provides a method and equipment for cell switching, which can reduce signaling overhead in the switching process of terminal equipment.

In a first aspect, a method for cell handover is provided, including: the terminal equipment acquires first information from a system message, wherein the first information is used for the terminal equipment to carry out cell switching.

In a second aspect, a method for cell handover is provided, including: the network equipment sends a system message to the terminal equipment, wherein the system message comprises first information, and the first information is used for the terminal equipment to carry out cell switching.

In a third aspect, a terminal device is provided, configured to perform the method in the first aspect or each implementation manner thereof.

Specifically, the terminal device includes a functional module for executing the method in the first aspect or each implementation manner thereof.

In a fourth aspect, a network device is provided for performing the method of the second aspect or its implementation manners.

In particular, the network device comprises functional modules for performing the methods of the second aspect or its implementations described above.

In a fifth aspect, a terminal device is provided that includes a processor and a memory. The memory is used for storing a computer program, and the processor is used for calling and running the computer program stored in the memory, and executing the method in the first aspect or each implementation manner thereof.

In a sixth aspect, a network device is provided that includes a processor and a memory. The memory is used for storing a computer program, and the processor is used for calling and running the computer program stored in the memory, and executing the method of the second aspect or each implementation mode thereof.

In a seventh aspect, an apparatus is provided for implementing the method in any one of the first to second aspects or implementations thereof.

Specifically, the apparatus includes: a processor configured to call and run the computer program from the memory, so that the apparatus on which the apparatus is installed performs the method according to any one of the first aspect to the second aspect or the implementation manner thereof.

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

In a ninth aspect, there is provided a computer program product comprising computer program instructions to cause a computer to perform the method of any one of the first to second aspects or implementations thereof.

A tenth aspect provides a computer program that, when run on a computer, causes the computer to perform the method of any one of the first to second aspects or implementations thereof.

Through the technical scheme, the network equipment can send the relevant information for cell switching to the terminal equipment through the system message, so that the network equipment is prevented from sending all the relevant information for cell switching to the terminal equipment through the special signaling, and the expense of the special signaling can be saved.

Drawings

Fig. 1 is a schematic diagram of a wireless communication system to which an embodiment of the present application is applied.

Fig. 2 is a schematic diagram of a contention-based random access procedure according to an embodiment of the present application.

Fig. 3 is a schematic diagram of a non-contention based random access procedure according to an embodiment of the present application.

Fig. 4 is a schematic diagram of a cell handover method according to an embodiment of the present application.

Fig. 5 is a schematic diagram of a handover procedure based on condition triggering according to an embodiment of the present application.

Fig. 6 is a schematic flowchart of a method for cell handover according to an embodiment of the present application.

Fig. 7 is a schematic block diagram of a terminal device according to an embodiment of the present application.

Fig. 8 is a schematic block diagram of a network device according to an embodiment of the present application.

Fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application.

Fig. 10 is a schematic structural diagram of an apparatus provided in an embodiment of the present application.

Fig. 11 is a schematic block diagram of a communication system according to an embodiment of the present application.

Detailed Description

Fig. 1 is a schematic diagram of a system 100 according to an embodiment of the present application.

As shown in fig. 1, the terminal device 110 is connected to a first network device 130 under a first communication system and a second network device 120 under a second communication system, for example, the first network device 130 is a network device under Long Term Evolution (LTE), and the second network device 120 is a network device under New Radio (NR).

The first network device 130 and the second network device 120 may include a plurality of cells.

It should be understood that fig. 1 is an example of a communication system of the embodiment of the present application, and the embodiment of the present application is not limited to that shown in fig. 1.

As an example, a communication system adapted by the embodiment of the present application may include at least a plurality of network devices under the first communication system and/or a plurality of network devices under the second communication system.

For example, the system 100 shown in fig. 1 may include one primary network device under a first communication system and at least one secondary network device under a second communication system. At least one auxiliary network device is connected to the one main network device, respectively, to form a multi-connection, and is connected to the terminal device 110, respectively, to provide a service thereto. In particular, terminal device 110 may establish a connection through both the primary network device and the secondary network device.

Optionally, the connection established between the terminal device 110 and the primary network device is a primary connection, and the connection established between the terminal device 110 and the auxiliary network device is an auxiliary connection. The control signaling of the terminal device 110 may be transmitted through the main connection, and the data of the terminal device 110 may be transmitted through the main connection and the auxiliary connection simultaneously, or may be transmitted through only the auxiliary connection.

As still another example, the first communication system and the second communication system in the embodiment of the present application are different, but the specific category of the first communication system and the second communication system is not limited.

For example, the first communication system and the second communication system may be various communication systems, such as: a Global System for Mobile communications (GSM) System, a Code Division Multiple Access (CDMA) System, a Wideband Code Division Multiple Access (WCDMA) System, a General Packet Radio Service (GPRS), a Long Term Evolution (Long Term Evolution, LTE) System, a Time Division Duplex (TDD), a Universal Mobile Telecommunications System (UMTS), and the like.

The primary network device and the secondary network device may be any access network device.

Optionally, in some embodiments, the Access network device may be a Base Transceiver Station (BTS) in a Global System for Mobile communications (GSM) System or a Code Division Multiple Access (CDMA) System, a Base Station (NodeB, NB) in a Wideband Code Division Multiple Access (WCDMA) System, or an evolved Node B (eNB or eNodeB) in a Long Term Evolution (Long Term Evolution) System.

Optionally, the Access Network device may also be a Next Generation Radio Access Network (NG RAN), or a base station (gNB) in an NR system, or a wireless controller in a Cloud Radio Access Network (CRAN), or the Access Network device may be a relay station, an Access point, a vehicle-mounted device, a wearable device, or a Network device in a Public Land Mobile Network (PLMN) for future evolution, or the like.

In the system 100 shown in fig. 1, the first network device 130 is taken as a main network device, and the second network device 120 is taken as an auxiliary network device.

The first network device 130 may be an LTE network device and the second network device 120 may be an NR network device. Alternatively, the first network device 130 may be an NR network device and the second network device 120 may be an LTE network device. Or both the first network device 130 and the second network device 120 may be NR network devices. Alternatively, the first network device 130 may be a GSM network device, a CDMA network device, etc., and the second network device 120 may also be a GSM network device, a CDMA network device, etc. Alternatively, the first network device 130 may be a macro base station (Macrocell), and the second network device 120 may be a microcellular base station (Microcell), a picocellular base station (Picocell), a Femtocell base station (Femtocell), or the like.

Optionally, the terminal device 110 may be any terminal device, and the terminal device 110 includes but is not limited to:

via a wireline connection, such as via a Public Switched Telephone Network (PSTN), a Digital Subscriber Line (DSL), a Digital cable, a direct cable connection; and/or another data connection/network; and/or via a Wireless interface, e.g., to a cellular Network, a Wireless Local Area Network (WLAN), a digital television Network such as a DVB-H Network, a satellite Network, an AM-FM broadcast transmitter; and/or means of another terminal device arranged to receive/transmit communication signals; and/or Internet of Things (IoT) devices. A terminal device arranged to communicate over a wireless interface may be referred to as a "wireless communication terminal", "wireless terminal", or "mobile terminal". Examples of mobile terminals include, but are not limited to, satellite or cellular telephones; personal Communications Systems (PCS) terminals that may combine cellular radiotelephones with data processing, facsimile, and data Communications capabilities; PDAs that may include radiotelephones, pagers, internet/intranet access, Web browsers, notepads, calendars, and/or Global Positioning System (GPS) receivers; and conventional laptop and/or palmtop receivers or other electronic devices that include a radiotelephone transceiver. Terminal Equipment may refer to an access terminal, User Equipment (UE), subscriber unit, subscriber station, mobile station, remote terminal, mobile device, User terminal, wireless communication device, User agent, or User Equipment. An access terminal may be a cellular telephone, a cordless telephone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device having 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 5G network, or a terminal device in a future evolved PLMN, etc.

It should be understood that the terms "system" and "network" are often used interchangeably herein.

In this embodiment of the present application, a network device provides a service for a cell, and a terminal device communicates with the network device through a transmission resource (for example, a frequency domain resource or a spectrum resource) used by the cell, where the cell may be a cell corresponding to the network device (for example, a base station), and the cell may belong to a macro base station or a base station corresponding to a Small cell (Small cell), where the Small cell may include: urban cells (Metro cells), Micro cells (Micro cells), Pico cells (Pico cells), Femto cells (Femto cells), and the like, and the small cells have the characteristics of small coverage area and low transmission power, and are suitable for providing high-rate data transmission services.

It should be understood that the method of the embodiments of the present application may be used to transmit various types of services.

For example, the demand for eMBB, which targets users to obtain multimedia content, services and data, is growing very rapidly. For another example, the eMBB may be deployed in different scenarios, such as indoor, urban, rural, etc., and the difference between the capabilities and the requirements of the eMBB is relatively large, so the eMBB may be analyzed in detail in combination with a specific deployment scenario. Also for example URLLC, typical applications of URLLC include: industrial automation, electric power automation, remote medical operation (surgery), traffic safety, and the like. Typical characteristics of mtc include: high connection density, small data volume, insensitive time delay service, low cost and long service life of the module, etc.

In some special scenarios, the terminal device needs to initiate random access to the network device to establish a connection with the network device. There are various events that trigger the terminal device to perform random access, for example, in the initial access process of the terminal device; in the process of rebuilding the terminal equipment; when the terminal equipment has uplink data to be sent but detects uplink desynchronizing; when the terminal equipment has uplink data to be sent but does not have Scheduling Request (SR) resources; under the condition that the terminal equipment needs to carry out cell switching; when the base station has downlink data to be sent but detects that the uplink is out of step.

The random access of the terminal device may include contention-based random access and non-contention-based random access.

The contention-based random access procedure may be as described with reference to fig. 2.

S210, the terminal device transmits a message 1(message1, MSG1) to the network device on the random access channel, and the MSG1 includes the random access preamble. Wherein the MSG1 may be a physical layer message.

S220, after receiving the MSG1, the network device may send the MSG2 on a downlink shared channel (DL-SCH), where the MSG2 may be a Random Access Response (RAR). The MSG2 may be a MAC layer message.

The RAR response carries uplink resource information that can be used and Timing Advance (TA) adjustment of uplink transmission and temporary cell radio network temporary identifier (T-CRNTI), that is, a temporary CRNTI.

Alternatively, the RAR response may be generated by a Media Access Control (MAC) layer of the network device. One MSG2 may correspond to multiple terminal device random access request responses simultaneously.

In S230, the terminal device, upon receiving MSG2, determines whether it belongs to its RAR message, and if it is determined that it belongs to its RAR message, transmits message 3(message3, MSG3) in the uplink resource designated by MSG2, where MSG3 carries the terminal-specific RNTI. The MSG3 may be an RRC layer message.

In step 240, the network device, after receiving the MSG3, may send an MSG4 message to the terminal device. The MSG4 includes contention resolution information and uplink transmission resources allocated by the network device to the terminal device. The MSG4 may be a MAC layer message.

After receiving the MSG4, the terminal device may detect whether the specific RNTI transmitted in the MSG3 is included in the contention resolution message transmitted by the network device. If yes, the random access process of the terminal equipment is indicated to be successful, otherwise, the random access process is considered to be failed. After the random access procedure fails, the terminal device needs to initiate the random access procedure from the first step again.

Alternatively, MSG1 and MSG2 may not use the HARQ mechanism, and MSG3 and MSG4 may use the HARQ mechanism.

If one random access attempt fails, the terminal device may further initiate the next random access attempt until the maximum retransmission times and/or the maximum retransmission time allowed by the network side are reached.

Terminal devices typically perform random access by transmitting a preamble to the network device. If the terminal device fails to perform the current random access after transmitting the preamble for the first time, the terminal device may transmit the preamble for the random access to the network device for a second time, and the transmission power of the preamble for the second time may be the transmission power of the preamble for the first time after the power ramp-up. The step size of the power ramp may be configured by the network device or may be pre-configured in the terminal device.

The non-contention based random access procedure may be as shown in fig. 3, for example.

S310, the network device sends MSG0 to the terminal device, and the MSG0 may include a preamble configuration message for indicating a preamble of the random access. The MSG0 may be a physical layer message.

S320, the terminal device sends MSG1 to the network device, and the MSG1 includes the random access preamble in S310. The MSG1 may be a physical layer message.

S330, the network device sends MSG2 to the terminal device, where MSG2 may be a random access response message. The MSG2 may be a MAC layer message.

In the non-contention based random access process, the terminal device may acquire a resource of non-contention random access through RRC signaling and/or PDCCH signaling, and perform random access on the non-contention random access resource.

The following describes a random access procedure of the terminal device by taking a handover procedure as an example. In the embodiment of the present application, a communication scenario of a handover process is not specifically limited, and for example, the communication scenario may be an LTE system or an NR system.

When a terminal device using network service moves from a source cell to a coverage area of a target cell, or due to reasons such as adjustment of wireless transmission service load, activation of operation maintenance, and device failure, in order to ensure continuity of terminal device communication and quality of service, a communication system needs to transfer a communication link between the terminal device and the source cell to the target cell, that is, to perform a cell handover procedure. The source cell may be understood as a cell to which the terminal device is currently connected, and the target cell may be understood as a cell to which the terminal device is to be handed over.

The cell handover method of the terminal device in the embodiment of the present application is not particularly limited, for example, the terminal device may perform an intra-site handover, that is, the source cell and the target cell belong to the same base station. For another example, the terminal device may perform handover between base stations, that is, the source cell and the target cell belong to different base stations.

The embodiment of the present application does not limit the interface used for performing cell handover between base stations. For example, the cell handover may be based on an X2 interface or an Xn interface, or may also be based on an S1 interface or an N2 interface.

Taking an Xn interface as an example, the switching process of the terminal device can be divided into the following three stages: handover preparation, handover execution, and handover completion.

The handover preparation may include the terminal device measuring and reporting the link quality, sending a handover request to the source base station, and receiving a handover command sent by the source base station.

The handover execution may include the terminal device performing the handover procedure immediately after receiving the handover command sent by the source base station. For example, the connection with the source cell may be broken and the connection with the target cell may be completed (e.g., performing random access, sending an RRC handover complete message to the target base station, etc.), Serial Number (SN) status transfer, data forwarding, and so on.

The handover completion may include the target cell performing link handover with an access and mobility management function (AMF) and a User Plane Function (UPF), releasing the UE context of the source base station, and the like.

For the NR system, the link switching and releasing the UE context of the source base station may be performed by the AMF and the UPF, and for the LTE system, the link switching and releasing the UE context of the source base station may be performed by the MME. The embodiment of the present application does not specifically limit the applicable system, and may be applied to an LTE system or an NR system.

Specifically, as shown in FIG. 4, the handover preparation phase (401-405) may include:

in 401, the source base station triggers the terminal device to perform neighbor cell measurement, so that the terminal device can perform measurement on the neighbor cell and report the measurement result to the source base station.

In 402, the source base station evaluates the measurement result reported by the terminal device, and determines whether to trigger handover.

In 403, if the source base station decides to trigger handover, it may send a handover request to the target base station.

In 404, after receiving the handover request sent by the source base station, the target base station may start admission according to the service information carried by the source base station, and perform radio resource configuration.

In 405, the target base station sends a handover request acknowledgement message to the source base station, and returns an admission result and radio resource configuration information in the target base station to the source base station. At this point, the handover preparation phase is complete.

In the second phase, the handover execution phases (406-408) may include:

in 406, after receiving the handover request acknowledge message of the target base station, the source base station may trigger the terminal device to perform handover.

In 407, the source base station may forward buffered data, on-going packets, system sequence numbers of the data, etc. to the target base station. Also, the target base station may buffer data received from the source base station

In addition, the terminal equipment can disconnect from the source base station and establish synchronization with the target base station.

In 408, the terminal device synchronizes to the target base station. At this point, the handover execution phase is complete.

In the third stage, the handover completion stage (409 ~ 412) may include:

in 409, the target base station sends a path switch request to a Mobility Management Function (AMF).

In 410, after receiving the path switch request from the target base station, the AMF performs path switch with a User Plane Function (UPF) and clears the path flag of the User Plane of the source base station.

In 411, after the path switch is completed, the AMF may transmit a path switch confirm message to the target base station.

In 412, the target base station sends a terminal device context release message to the source base station, informs the source base station of successful handover, and triggers the source base station to release the terminal device context. At this point, the handover is completed.

The terminal equipment starts a T304 timer immediately after receiving the switching command, starts downlink synchronization to a target cell, acquires Master Information Block (MIB) information of the target cell, and then initiates random access. And allowing a plurality of preamble retransmissions in the random access process until the random access is successful. Further, if the T304 timer expires, which indicates a handover failure, the terminal device may directly trigger the RRC connection reestablishment procedure.

The handover procedure in this way is a completely network controlled handover procedure. However, it is necessary to perform frequent switching for a terminal device moving at a high speed or under a high frequency condition. If the cell switching is performed in the above manner, the terminal device may not be able to send the measurement report or receive the switching command when moving to an area with poor coverage at a high speed, which may cause the terminal device to be unable to perform cell switching, resulting in service interruption and other problems.

The embodiment of the application provides a switching process based on condition triggering, which can avoid the problem that the switching preparation time is too long, and the terminal equipment is too late to switch the cell.

The network device may configure the terminal device with the handover command in advance, and the network device may also allocate the target base station to the terminal device in advance. The handover command may include a condition for triggering the terminal device to perform handover, and when it is detected that the target cell satisfies the handover condition, the terminal device may initiate an access request to the target base station.

The handover trigger condition may be a trigger condition based on signal quality. For example, the handover trigger condition may include the signal quality of the source cell being below a first threshold. The terminal device may perform a cell handover if the terminal device detects that the signal quality of the source cell is below a first threshold. As another example, the handover trigger condition may include a signal quality of the target cell being above a second threshold. The terminal device may perform a handover to the target cell if the terminal device detects that the signal quality of the target cell is above the second threshold. For another example, the handover triggering condition may include that the signal quality of the source cell is lower than a first threshold, and the signal quality of the target cell is higher than a second threshold, and the terminal device may perform handover to the target cell only if both conditions are satisfied.

The first threshold and the second threshold may be the same or different. This is not particularly limited in the embodiments of the present application.

The signal quality of a cell may be characterized by a Reference Signal Receiving Power (RSRP). The terminal device may receive reference signals of the source cell and the target cell, and measure received power of the reference signals to obtain RSRP corresponding to the cells. The larger the RSRP value is, the better the signal quality of the cell is; the smaller the RSRP value, the worse the signal quality of the cell.

The procedure based on conditional switch is described below with reference to fig. 5.

The source base station sends 510 measurement configuration information to the terminal device.

The terminal device sends 520 a measurement report to the source base station.

And 530, the source base station and the target base station exchange switching preparation information.

540, the source base station sends a handover command to the terminal device.

The handover command includes condition information for a cell or a beam.

And 550, synchronizing the terminal equipment with the target base station when the condition is met (the terminal equipment is accessed to the target base station).

However, for a specific handover scenario, such as a high-speed rail scenario, the network device also needs to configure a plurality of target cells in advance to the terminal device. However, for a plurality of terminal devices on a high-speed rail, the network device needs to configure a plurality of target cells to the plurality of terminal devices, respectively. However, the operation track of the terminal device on the high-speed rail is determined, and there is a problem that the network device repeatedly sends the same information to a plurality of terminal devices, and if the network device separately configures a plurality of target cells to a plurality of terminal devices by using dedicated signaling, waste of signaling resources is caused.

Similar problems exist for non-terrestrial network communication systems. For example, for a Low Earth Orbit (LEO) system, since LEO satellites are not stationary with respect to the ground but move at a high speed, the moving speed with respect to the ground can reach 7.75km/s, i.e., 27216km/h, and the moving speed is much higher than that of a general ground or aerial vehicle.

Therefore, for a terminal device that uses a LEO satellite for communication, a problem of satellite switching by the terminal device may be caused due to relative movement between the LEO satellite and the terminal device on the ground. And since the trajectory of the satellite is determined, the trajectory of the terminal device with respect to the LEO satellite is determined according to the principle of relative motion. Therefore, for LEO satellite communication systems, conditional based handover may also be employed to address satellite movement. The LEO satellite may configure other LEO satellites and handover conditions to the terminal device in advance, so that the terminal device may handover to the target LEO satellite when detecting that the handover conditions are satisfied.

However, the LEO communication system faces more serious problems than a general terrestrial communication system:

1. in time, the movement speed of LEO is higher than that of general vehicles, and reaches the order of 100x, that is, in the same time range, the LEO communication system needs to process 100x movement events.

2. Spatially, the coverage of a LEO satellite is much larger than that of a general cell of a terrestrial network, and the coverage can reach tens or hundreds of kilometers. The number of single-cell users of non-terrestrial networks can reach large values depending on the density of users in the coverage area using LEO satellite communications. Similarly, because of the large range of LEO satellites, there are more terminal devices using the same LEO satellite, and one LEO satellite handles more terminal device movement events.

Therefore, with LEO satellites, since the orbit of the LEO satellite is determined, if the LEO satellite configures a plurality of target LEO satellites to each terminal device separately using dedicated signaling, there is also a problem of repeatedly transmitting the same information to a plurality of terminal devices, and the problem of the LEO communication system is more serious than that of the terrestrial communication system. This results in more wasted signaling because more terminal devices need to be configured with the target LEO satellite at the same time.

Therefore, for the terminal device in a deterministic high-speed moving state, how the network device instructs the terminal device to perform cell handover becomes an urgent problem to be solved at present.

The embodiment of the application provides a method for cell switching, which can reduce signaling overhead in a switching process. As shown in fig. 6, the method includes S610.

S610, the network equipment sends a system message to the terminal equipment, wherein the system message comprises first information, and the first information is used for the terminal equipment to carry out cell switching.

The network device may broadcast the system message to the terminal device, and after receiving the system message, the terminal device may obtain the first information from the system message to perform cell handover. Alternatively, the network device may refer to a source base station.

The first information may include at least one of the following information: configuration information of the candidate target cell, a T304 timer, dedicated configuration information for random access and handover conditions for handover to the candidate target cell.

The candidate target cells may include one target cell or may include a plurality of target cells. The network device may configure one or more target cells to the terminal device in advance to facilitate handover of the terminal device to the target cells.

Candidate target cells may include non-terrestrial network (NTN) cells, such as LEO cells; the candidate target cell may also be a ground network cell, which is not specifically limited in this embodiment of the present application.

The configuration information of the candidate target cell may include at least one of the following information: a relative configuration of an uplink, a relative configuration of a downlink, a Synchronization Signal Block (SSB) relative configuration, and a reference signal relative configuration. The configuration information of the candidate target cell may include configuration information of the primary and secondary cells.

The T304 timer may be started when the terminal device receives the handover command, and the terminal device may initiate random access to the target cell after receiving the handover command. For the switching process based on the condition switching, the T304 timer may also be started when the terminal device determines by itself that the switching condition is satisfied and triggers the switching action. After the T304 timer expires, it indicates that the terminal device fails random access. The T304 timers of different target cells may be the same or different.

The dedicated configuration information for random access is used for the terminal device to initiate random access to the target cell, and the dedicated configuration information for random access of different target cells may be the same or different. The dedicated configuration information for random access may include, for example, a random access preamble or the like.

The handover condition of the candidate target cell may include at least one of the following conditions: the signal quality of the candidate target cell and the position of the terminal device relative to the target cell.

For the cell switching method for the signal quality of the target cell, when the terminal device detects that the signal quality of the target cell meets a certain switching condition, the terminal device may switch to the target cell, and the specific method may refer to the above description, which is not described herein again.

For the situation of the position of the terminal device relative to the target cell, the embodiment of the present application does not specifically limit the handover condition for triggering the handover. For example, the terminal device is handed over to the target cell as soon as it comes within the coverage of the target cell. For another example, the terminal device may enter the range of the target cell and switch to the target cell after being located at the edge of the source cell.

Of course, the handover condition of the candidate target cell may be a combination of the above conditions, for example, when the terminal device performs handover, it is necessary to consider not only the position of the terminal device relative to the target cell, but also determine whether the signal quality of the target cell satisfies the condition.

For a terminal device moving at a high speed, the network device may configure relevant information for cell handover to the terminal device in advance. In the embodiment of the application, the relevant information configured by the network device to the terminal device for cell handover is not configured through dedicated signaling, but part or all of the relevant information can be configured through system messages, so that the overhead of the dedicated signaling can be reduced.

For the terminal devices on a high-speed rail, since the operation trajectories of all the terminal devices are the same, the candidate target cells configured by the network device to the terminal devices may also be the same. For example, the network device may send the same configuration information of the candidate target cell to all the terminal devices through the system message, and does not need to send the same information to each terminal device separately.

For a non-terrestrial communication system, such as a LEO satellite communication system, a LEO satellite can configure the first information to all terminal devices within its coverage area through system messages without repeatedly sending the first information to the terminal devices, which can save signaling overhead.

As an implementation manner, the network device may further send a dedicated signaling to the terminal device, where the dedicated signaling may include at least one of the following information: identification information of the terminal device in the candidate target cell, a T304 timer, special configuration information for random access and a switching condition for switching to the candidate target cell.

The dedicated signaling may be understood as a message sent by the network device to the terminal device in a unicast manner.

The identification information of the terminal device in the candidate target cell may be, for example, a cell radio network temporary identifier (C-RNTI).

The C-RNTI may be a request sent by the target base station to the source base station after the source base station sends a handover request to the target base station, and then the source base station may send the C-RNTI to the terminal device through a dedicated signaling. The C-RNTIs of different terminal devices in the same target base station are different, so that the C-RNTI information sent by the source base station to the terminal device is sent through a special signaling. And when the terminal equipment needs to be switched to the target base station, the terminal equipment can adopt the C-RNTI to carry out random access to the target base station.

The system message and the dedicated signaling may comprise the same information, e.g. may each comprise second information, wherein the second information comprises at least one of the following information: t304 timer, dedicated configuration information for random access and handover condition to candidate target cell. Different information may also be included in the system message and the dedicated signaling, for example, the system message may include configuration information of the candidate target cell, and the dedicated signaling may include identification information of the terminal device in the candidate target cell.

In this embodiment, the network device may broadcast the configuration information of the candidate target cell to the terminal device through the system information, and place the identification information of the terminal device in the candidate target cell in a dedicated signaling to send to the terminal device. For the T304 timer, the dedicated configuration information for random access, and the handover condition for handover to the candidate target cell, the network device may broadcast in the system message to the terminal device, or may send the system message to the terminal device by using the dedicated signaling.

For some information included in both the system message and the dedicated signaling, that is, some information already included in the system message is included in the dedicated signaling, the terminal device may perform cell switching by using the information in the system message, or may perform cell switching by using the information in the dedicated signaling.

As an example, the terminal device may preferentially employ information in the dedicated signaling for cell handover. Assuming that the system message and the dedicated signaling both include the T304 timer, the terminal device preferentially uses the T304 timer in the dedicated signaling for cell handover.

After receiving the system message and the dedicated signaling, the terminal device can perform cell switching according to the information in the dedicated signaling. For information not included in the dedicated signaling, the terminal device may obtain from the system message for cell handover.

As another example, the dedicated signaling may further include first indication information, and the network device may indicate to the terminal device by using the first indication information, where the information in the message is used for cell handover, for example, the first indication information may indicate whether the terminal device needs to perform cell handover based on the information in the system message. Still taking the T304 timer as an example, the system message and the dedicated signaling both include the T304 timer, the network device may further configure first indication information in the dedicated signaling, and if the first indication information indicates that the terminal device performs cell handover based on the T304 timer in the system information, the terminal device makes the T304 timer of the system message perform cell handover; and if the first indication information indicates that the terminal equipment does not perform cell switching based on the T304 timer in the system message or indicates that the terminal equipment performs cell switching based on the T304 timer in the special signaling, the terminal equipment performs cell switching by using the T304 timer in the special signaling.

The dedicated configuration information for random access and the handover condition for handover to the candidate target cell, if included in the system message and the dedicated signaling, may also be used in the manner described above to determine which message the terminal device should use for handover.

The method provided by the embodiment of the application can be applied to the switching process based on the conditional switching and can also be applied to the switching process based on the unconditional switching.

For the switching mode based on the conditional switching, after receiving the system message sent by the network device, the terminal device may detect the target cell according to the switching condition included in the system message, and when detecting that the target cell satisfies the switching condition, the terminal device may directly initiate random access to the target cell satisfying the condition to switch to the target cell.

For the switching mode based on the unconditional switching, the network equipment can still configure the first information to the terminal equipment through the system message in advance. When the terminal device needs to perform handover, the terminal device may send a handover request to the network device by using a conventional handover manner based on unconditional handover, and the network device may send a handover command to the terminal device, except that the handover command may only include a target cell to which the terminal device should be handed over, and does not need to send configuration information of the target cell to the terminal device. After receiving the handover command, the terminal device may obtain configuration information corresponding to the target cell from the system message according to an indication in the handover command, so as to perform cell handover. This way also the signalling overhead during handover can be saved.

The candidate target cells may include multiple target cells, that is, the system message may include configuration information of multiple candidate target cells, and the network device may indicate to the terminal device through dedicated signaling which target cell configuration information is used to perform handover. For example, second indication information may be included in the dedicated signaling, and the second indication information may be used to instruct the terminal device to switch to a first target cell of the multiple target cells. After receiving the dedicated signaling, the terminal device may perform cell handover according to the relevant information of the first target cell included in the system message and/or the dedicated signaling.

As an example, for the condition-based handover procedure, after receiving the dedicated signaling, the terminal device may first perform handover to the first target cell after the first target cell meets the handover condition according to the handover condition for handover to the first target cell included in the system message and/or the dedicated signaling. When the terminal device is switched to the first target cell, the terminal device may initiate random access to the first target cell according to the relevant information of the first target cell included in the system message and/or the dedicated signaling.

As yet another example, for an unconditional based handover procedure, the terminal device may initiate random access to the first target cell directly according to the relevant information of the first target cell included in the system message and/or the dedicated signaling after receiving the dedicated signaling. The dedicated signaling may be a handover command.

The system message in the embodiment of the present application may be a system message dedicated to handover, for example, the system message may be a system message dedicated to carrying the first information. The system message dedicated for handover may mean that the system message is different from other system messages existing in the protocol, or the system message does not multiplex the existing system messages, but adds a system message dedicated for carrying information used for handover of the terminal device on the basis of the existing system messages.

Alternatively, the system message may be a System Information Block (SIB) message.

The system message may be a system message dedicated to carry the NTN system, that is, the system message may be a system message for a terminal device using the NTN system. Alternatively, the system message may be a system message dedicated to the bearer terrestrial network system, i.e., the system message may be a system message for a terminal device using the terrestrial system.

Before the terminal device receives the system message, the network device may also send the receiving location of the system message to the terminal device. For example, the network device may send, to the terminal device, third indication information, where the third indication information is used to indicate a location of the time domain resource and/or the frequency domain resource that receives the system message, and the location of the time domain resource and/or the frequency domain resource may also be referred to as a configuration parameter of the time domain resource and/or the frequency domain resource. After receiving the third indication information, the terminal device may receive the system message in response at the location of the time domain resource and/or the frequency domain resource indicated by the third indication information.

The configuration parameters of the time domain resources and/or the frequency domain resources may include, for example, Measurement Time Configurations (MTC) of the SSBs.

The third indication information may be used to indicate that the connected terminal device receives the system message.

In the case of a non-terrestrial network communication system, after the terminal device identifies that the cell is an NTN cell (e.g., an LEO cell), it may actively receive system messages after switching to the cell.

The cell in which the terminal device is located before the handover is the first cell, and the system message may be received after the terminal device is connected to the first cell, that is, the terminal device may receive the system message sent by the base station of the first cell according to the third indication information sent by the base station in which the first cell is located after being connected to the first cell.

The first cell is not specifically limited in the embodiments of the present application, as long as the first cell is a cell where the terminal device is located before handover. For example, the first cell may be a cell in which the terminal device is currently located, or the first cell may be any cell in which the terminal device is handed over to a cell in which the terminal device is currently located. That is, the system message received by the terminal device can be used in multiple handover procedures.

For example, the cell in which the terminal device is currently located is cell 1, and the cell in which the terminal device is located before being switched to cell 1 is cell 0. The terminal device needs to switch from the cell 1 to the cell 2 due to high-speed movement, and the terminal device acquires the information related to the cell 2 by using a system message, wherein the system message may be sent by the base station where the cell 1 is located or the base station where the cell 0 is located.

Similarly, the indication information of the positions of the time domain resource and the frequency domain resource of the received system message may be transmitted by the base station in which the cell 1 is located, or may be transmitted by the base station in which the cell 0 is located.

When the network device broadcasts the related information of multiple target cells, the related information of multiple target cells can be placed in the same system message for broadcasting, so that the broadcast signaling overhead can be saved, and the signaling overhead can be further saved. Alternatively, the network device may also use different system messages to broadcast the related information of different target cells, that is, each system message only broadcasts the related information of one target cell, which can provide more flexible network configuration.

The network device in the embodiment of the present application may refer to a source base station, which may also be referred to as a source cell base station, where the source base station may be configured to broadcast a system message to a terminal device, and may also send a dedicated signaling to the terminal device. The network device in the embodiment of the present application may also refer to a target base station, which may also be referred to as a target cell base station, where the target base station may be used for performing random access by a terminal device.

For the sake of easy understanding, the application examples are described in detail below with reference to specific examples.

For a highly mobile terminal device, a cell in which the terminal device is currently located is cell 0, a base station in which cell 0 is located is base station 0, the base station 0 detects that the terminal device is in a high-speed moving state, and an operation track of the terminal device is determined, then the base station 0 can configure a plurality of target cells along the track to the terminal device according to the operation track of the terminal device. The related information of the target cells may be, for example, the first information described above, and the related information of the target cells may be sent to the terminal device through a system message. The base station 0 may further send third indication information to the terminal device, where the third indication information is used to indicate the terminal device to receive the configuration parameters of the time domain resource and/or the frequency domain resource of the system message, and after receiving the third indication information, the terminal device receives the system message on the corresponding time domain resource and/or frequency domain resource.

Assuming that the plurality of target cells may include cell 1 and cell 2, the information related to cell 1 may include information required for handover to cell 1, such as handover conditions that need to be satisfied for handover to cell 1, information required for initiating random access to cell 1, and the like. Similarly, the information related to the cell 2 may include information required to handover to the cell 2, such as a handover condition that needs to be satisfied to handover to the cell 2, information required to initiate random access to the cell 2, and the like. The base station in which the cell 1 is located may be referred to as a base station 1, and the base station in which the cell 2 is located may be referred to as a base station 2.

The information related to the cell 1 and the information related to the cell 2 may be carried in the same system message, for example, the base station 0 may send the system messages of the cell 1 and the cell 2 to the terminal device by broadcasting a system message. Alternatively, the related information of the cell 1 and the cell 2 may be carried in different system messages, for example, the base station 0 broadcasts the related information of the cell 1 by using the first system message, and broadcasts the related information of the cell 2 by using the second system message.

If the terminal device reaches the edge position of the cell 0 and/or enters the coverage area of the cell 1, the base station 0 may send instruction information instructing to switch to the cell 1 to the terminal device, and the terminal device switches to the cell 1 according to the instruction of the base station 0; or the terminal device may determine that the cell 1 satisfies the handover condition according to the handover condition for handover to the cell 1 in the system information, and then switch to the cell 1. Before switching to the cell 1, the terminal device may acquire the relevant parameter of the cell 1 from the previously acquired system message, and switch to the cell 1 based on the relevant parameter of the cell 1.

Along with the movement of the terminal equipment, the terminal equipment can reach the edge position of the cell 1 and/or enter the coverage range of the cell 2, the base station 1 can send indication information indicating switching to the cell 2 to the terminal equipment, and the terminal equipment can be switched to the cell 1 according to the indication of the base station 1; or the terminal device may also switch to the cell 2 after determining that the cell 2 satisfies the corresponding handover condition according to the handover condition for switching to the cell 2 in the system message sent by the base station 0.

Having described the wireless communication method according to the embodiment of the present application in detail above, an apparatus according to the embodiment of the present application will be described below with reference to fig. 7 to 11, and the technical features described in the method embodiment are applicable to the following apparatus embodiments.

Fig. 7 is a schematic block diagram of a terminal device according to an embodiment of the present application, where the terminal device may be any one of the terminal devices described above, and the terminal device 700 in fig. 7 includes an obtaining unit 710, where:

an obtaining unit 710, configured to obtain first information from a system message, where the first information is used for the terminal device to perform cell handover.

Optionally, the first information includes at least one of the following information: configuration information of the candidate target cell, a T304 timer, dedicated configuration information for random access and handover conditions for handover to the candidate target cell.

Optionally, the terminal device 700 further includes a receiving unit 720, configured to: receiving a dedicated signaling sent by a network device, wherein the dedicated signaling comprises at least one of the following information: identification information of the terminal device in the candidate target cell, a T304 timer, special configuration information for random access and a switching condition for switching to the candidate target cell.

Optionally, the candidate target cell comprises a non-terrestrial network NTN cell.

Optionally, the NTN cells comprise low earth orbit LEO cells.

Optionally, the terminal device 700 further includes a processing unit 730, configured to: and carrying out cell switching according to the information in the special signaling.

Optionally, the system message and the dedicated signaling each include second information, where the second information includes at least one of the following information: t304 timer for dedicated configuration information for random access and handover conditions for handover to a candidate target cell, the terminal device 700 further comprises a processing unit 730 for: and when the cell is switched, the cell is switched according to the second information in the special signaling.

Optionally, the dedicated signaling further includes first indication information, where the first indication information is used to indicate whether the terminal device performs cell handover based on information in the system message.

Optionally, the system message and the dedicated signaling each include second information, where the second information includes at least one of the following information: t304 timer, dedicated configuration information for random access and handover condition to candidate target cell.

Optionally, the candidate target cells include a plurality of target cells, and the dedicated signaling includes second indication information, where the second indication information is used to indicate that the terminal device is switched to a first target cell in the plurality of target cells.

Optionally, the terminal device 700 further includes a processing unit 730, configured to: and switching to the first target cell according to the special signaling and/or the switching condition for switching to the first target cell included in the system information.

Optionally, the terminal device 700 further includes a receiving unit 720, configured to: and receiving third indication information sent by the network equipment, wherein the third indication information is used for indicating the position of the time domain resource and/or the frequency domain resource of the system message.

Optionally, the system message is a system message dedicated to carrying the first information.

Optionally, the system message is a system message dedicated to the NTN system.

Optionally, the cell where the terminal device is located before the handover is the first cell, and the terminal device 700 further includes a receiving unit 720, configured to: receiving the system message after connecting to the first cell.

Fig. 8 is a schematic block diagram of a terminal device according to an embodiment of the present application, where the terminal device may be any one of the terminal devices described above, and the terminal device 800 of fig. 8 includes a sending unit 810, where:

a sending unit 810, configured to send a system message to a terminal device, where the system message includes first information, and the first information is used for the terminal device to perform cell handover.

Optionally, the sending unit 810 is further configured to: sending a special signaling to the terminal equipment, wherein the special signaling comprises at least one of the following information: identification information of the terminal device in the candidate target cell, a T304 timer, special configuration information for random access and a switching condition for switching to the candidate target cell.

Optionally, the NTN cells comprise low earth orbit LEO cells.

Optionally, the dedicated signaling includes first indication information, where the first indication information is used to indicate whether the terminal device performs cell handover based on information in the system message.

Optionally, the candidate target cells include a plurality of target cells, and the dedicated signaling includes second indication information, where the second indication information is used to indicate that the terminal device is handed over to a first target cell in the plurality of candidate cells.

Optionally, the sending unit 810 is further configured to: and sending third indication information to the terminal equipment, wherein the third indication information is used for indicating the position of the time domain resource and/or the frequency domain resource of the system message.

Optionally, the system message is a system message dedicated to the NTN system.

Optionally, the sending unit 810 is further configured to: and after the terminal equipment is connected to the first cell, sending the system message to the terminal equipment.

Fig. 9 is a schematic structural diagram of a communication device 900 according to an embodiment of the present application. The communication device 900 shown in fig. 9 includes a processor 910, and the processor 910 can call and run a computer program from a memory to implement the method in the embodiment of the present application.

Optionally, as shown in fig. 9, the communication device 900 may also include a memory 920. From the memory 920, the processor 910 can call and run a computer program to implement the method in the embodiment of the present application.

The memory 920 may be a separate device from the processor 910, or may be integrated in the processor 910.

Optionally, as shown in fig. 9, the communication device 900 may further include a transceiver 930, and the processor 910 may control the transceiver 930 to communicate with other devices, and specifically, may transmit information or data to the other devices or receive information or data transmitted by the other devices.

The transceiver 930 may include a transmitter and a receiver, among others. The transceiver 930 may further include one or more antennas.

Optionally, the communication device 900 may specifically be a network device in this embodiment, and the communication device 900 may implement a corresponding process implemented by the network device in each method in this embodiment, which is not described herein again for brevity.

Optionally, the communication device 900 may specifically be a mobile terminal/terminal device according to this embodiment, and the communication device 900 may implement a corresponding process implemented by the mobile terminal/terminal device in each method according to this embodiment, which is not described herein again for brevity.

Fig. 10 is a schematic structural view of an apparatus of an embodiment of the present application. The apparatus 1000 shown in fig. 10 includes a processor 1010, and the processor 1010 may call and execute a computer program from a memory to implement the method in the embodiment of the present application.

Optionally, as shown in fig. 10, the apparatus 1000 may further include a memory 1020. From the memory 1020, the processor 1010 may call and execute a computer program to implement the method in the embodiment of the present application.

The memory 1020 may be a separate device from the processor 1010 or may be integrated into the processor 1010.

Optionally, the apparatus 1000 may further comprise an input interface 1030. The processor 1010 may control the input interface 1030 to communicate with other devices or apparatuses, and in particular, may obtain information or data transmitted by other devices or apparatuses.

Optionally, the apparatus 1000 may further comprise an output interface 1040. The processor 1010 may control the output interface 1040 to communicate with other devices or apparatuses, and in particular, may output information or data to other devices or apparatuses.

Optionally, the apparatus may be applied to the network device in the embodiment of the present application, and the apparatus may implement the corresponding process implemented by the network device in each method in the embodiment of the present application, and for brevity, details are not described here again.

Optionally, the apparatus may be applied to the mobile terminal/terminal device in the embodiment of the present application, and the apparatus may implement the corresponding process implemented by the mobile terminal/terminal device in each method in the embodiment of the present application, and for brevity, no further description is given here.

It should be understood that the apparatuses mentioned in the embodiments of the present application may be a chip, and the chip may also be referred to as a system on chip, a system on chip or a system on chip.

Fig. 11 is a schematic block diagram of a communication system 1100 provided in an embodiment of the present application. As shown in fig. 11, the communication system 1100 includes a terminal device 1110 and a network device 1120.

The terminal device 1110 may be configured to implement the corresponding function implemented by the terminal device in the foregoing method, and the network device 1120 may be configured to implement the corresponding function implemented by the network device in the foregoing method, which is not described herein again for brevity.

It should be understood that the processor of the embodiments of the present application may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the above method embodiments may be performed by integrated logic circuits of hardware in a processor or instructions in the form of software. The Processor may be a general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, or discrete hardware components. The various methods, steps, and logic blocks disclosed in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in a memory, and a processor reads information in the memory and completes the steps of the method in combination with hardware of the processor.

It will be appreciated that the memory in the embodiments of the subject application can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The non-volatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable PROM (EEPROM), or a flash Memory. Volatile Memory can be Random Access Memory (RAM), which acts as external cache Memory. By way of example, but not limitation, many forms of RAM are available, such as Static random access memory (Static RAM, SRAM), Dynamic Random Access Memory (DRAM), Synchronous Dynamic random access memory (Synchronous DRAM, SDRAM), Double Data Rate Synchronous Dynamic random access memory (DDR SDRAM), Enhanced Synchronous SDRAM (ESDRAM), Synchronous link SDRAM (SLDRAM), and Direct Rambus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

It should be understood that the above memories are exemplary but not limiting illustrations, and for example, the memories in the embodiments of the present application may also be Static Random Access Memory (SRAM), dynamic random access memory (dynamic RAM, DRAM), Synchronous Dynamic Random Access Memory (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (enhanced SDRAM, ESDRAM), Synchronous Link DRAM (SLDRAM), Direct Rambus RAM (DR RAM), and the like. That is, the memory in the embodiments of the present application is intended to comprise, without being limited to, these and any other suitable types of memory.

The embodiment of the application also provides a computer readable storage medium for storing the computer program.

Optionally, the computer-readable storage medium may be applied to the network device in the embodiment of the present application, and the computer program enables the computer to execute the corresponding process implemented by the network device in each method in the embodiment of the present application, which is not described herein again for brevity.

Optionally, the computer-readable storage medium may be applied to the mobile terminal/terminal device in the embodiment of the present application, and the computer program enables the computer to execute the corresponding process implemented by the mobile terminal/terminal device in each method in the embodiment of the present application, which is not described herein again for brevity.

Embodiments of the present application also provide a computer program product comprising computer program instructions.

Optionally, the computer program product may be applied to the network device in the embodiment of the present application, and the computer program instructions enable the computer to execute corresponding processes implemented by the network device in the methods in the embodiment of the present application, which are not described herein again for brevity.

Optionally, the computer program product may be applied to the mobile terminal/terminal device in the embodiment 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 methods in the embodiment of the present application, which are not described herein again for brevity.

The embodiment of the application also provides a computer program.

Optionally, the computer program may be applied to the network device in the embodiment of the present application, and when the computer program runs on a computer, the computer is enabled to execute the corresponding process implemented by the network device in each method in the embodiment of the present application, and for brevity, details are not described here again.

Optionally, the computer program may be applied to the mobile terminal/terminal device in the embodiment of the present application, and when the computer program runs on a computer, the computer is enabled to execute the corresponding process implemented by the mobile terminal/terminal device in each method in the embodiment of the present application, which is not described herein again for brevity.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

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

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. With regard to such understanding, the technical solutions of the present application may be essentially implemented or contributed to by the prior art, or may be implemented in a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to perform all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

A method for cell handover, comprising:

the terminal equipment acquires first information from a system message, wherein the first information is used for the terminal equipment to carry out cell switching.
The method of claim 1, wherein the first information comprises at least one of the following information: configuration information of the candidate target cell, a T304 timer, dedicated configuration information for random access and handover conditions for handover to the candidate target cell.
The method according to claim 1 or 2, characterized in that the method further comprises:

the terminal equipment receives a special signaling sent by network equipment, wherein the special signaling comprises at least one of the following information: identification information of the terminal device in the candidate target cell, a T304 timer, special configuration information for random access and a switching condition for switching to the candidate target cell.
The method of claim 3, wherein the candidate target cell comprises a non-terrestrial network (NTN) cell.
The method of claim 4, wherein the NTN cells comprise low earth orbit LEO cells.
The method according to any one of claims 3-5, further comprising:

and the terminal equipment performs cell switching according to the information in the special signaling.
The method according to any of claims 3-6, wherein second information is included in both the system message and the dedicated signaling, the second information comprising at least one of: a T304 timer for dedicated configuration information for random access and handover conditions for handover to a candidate target cell, the method further comprising:

and when the terminal equipment carries out cell switching, carrying out cell switching according to the second information in the special signaling.
The method according to any of claims 3-5, wherein the dedicated signaling further comprises first indication information, and the first indication information is used for indicating whether the terminal device performs cell switching based on information in the system message.
The method according to any of the claim 8, wherein the system message and the dedicated signaling each comprise second information, and the second information comprises at least one of the following information: t304 timer, dedicated configuration information for random access and handover condition to candidate target cell.
The method according to any of claims 3-9, wherein the candidate target cells comprise a plurality of target cells, and wherein second indication information is included in the dedicated signaling, the second indication information being used to indicate the terminal device to handover to a first target cell of the plurality of target cells.
The method of claim 10, further comprising:

and the terminal equipment is switched to the first target cell according to the special signaling and/or the switching condition for switching to the first target cell included in the system information.
The method according to any one of claims 1-11, further comprising:

and the terminal equipment receives third indication information sent by network equipment, wherein the third indication information is used for indicating the position of the time domain resource and/or the frequency domain resource of the system message.
The method according to any of claims 1-12, wherein the system message is a system message dedicated to carrying the first information.
The method according to any of claims 1-13, wherein the system message is a system message dedicated to the NTN system.
The method according to any of claims 1-14, wherein the cell in which the terminal device was located before the handover is the first cell, the method further comprising:

and the terminal equipment receives the system message after connecting to the first cell.
A method for cell handover, comprising:

the network equipment sends a system message to the terminal equipment, wherein the system message comprises first information, and the first information is used for the terminal equipment to carry out cell switching.
The method of claim 16, wherein the first information comprises at least one of the following information: configuration information of the candidate target cell, a T304 timer, dedicated configuration information for random access and handover conditions for handover to the candidate target cell.
The method according to claim 16 or 17, further comprising:

the network equipment sends a special signaling to the terminal equipment, wherein the special signaling comprises at least one of the following information: identification information of the terminal device in the candidate target cell, a T304 timer, special configuration information for random access and a switching condition for switching to the candidate target cell.
The method of claim 18, wherein the candidate target cell comprises a non-terrestrial network (NTN) cell.
The method of claim 19, wherein the NTN cells comprise low earth orbit LEO cells.
The method according to any of claims 18-20, wherein a first indication information is included in the dedicated signaling, and the first indication information is used to indicate whether the terminal device performs cell handover based on information in the system message.
The method of claim 21, wherein the system message and the dedicated signaling each comprise second information, and wherein the second information comprises at least one of the following information: t304 timer, dedicated configuration information for random access and handover condition to candidate target cell.
The method according to any of claims 18-22, wherein the candidate target cells comprise a plurality of target cells, and wherein second indication information is included in the dedicated signaling, the second indication information being used to indicate the terminal device to handover to a first target cell of the plurality of candidate cells.
The method according to any one of claims 16-23, further comprising:

and the network equipment sends third indication information to the terminal equipment, wherein the third indication information is used for indicating the position of the time domain resource and/or the frequency domain resource of the system message.
The method according to any of claims 16-24, wherein the system message is a system message dedicated to carrying the first information.
The method according to any of claims 16-25, wherein the system message is a system message dedicated to the NTN system.
The method according to any of claims 16-26, wherein the cell in which the terminal device was located before the handover is the first cell, the method further comprising:

and the network equipment sends the system message to the terminal equipment after the terminal equipment is connected to the first cell.
A terminal device, comprising:

an obtaining unit, configured to obtain first information from a system message, where the first information is used for the terminal device to perform cell handover.
The terminal device of claim 26, wherein the first information comprises at least one of the following information: configuration information of the candidate target cell, a T304 timer, dedicated configuration information for random access and handover conditions for handover to the candidate target cell.
The terminal device according to claim 28 or 29, wherein the terminal device further comprises a receiving unit configured to:

receiving a dedicated signaling sent by a network device, wherein the dedicated signaling comprises at least one of the following information: identification information of the terminal device in the candidate target cell, a T304 timer, special configuration information for random access and a switching condition for switching to the candidate target cell.
The terminal device of claim 30, wherein the candidate target cell comprises a non-terrestrial network (NTN) cell.
The terminal device of claim 31, wherein the NTN cell comprises a low earth orbit LEO cell.
The terminal device according to any of claims 30-32, wherein the terminal device further comprises a processing unit configured to:

and carrying out cell switching according to the information in the special signaling.
The terminal device according to any of claims 30-33, wherein the system message and the dedicated signaling each comprise second information, the second information comprising at least one of the following information: a T304 timer, configured to randomly access the dedicated configuration information and handover conditions for handover to the candidate target cell, where the terminal device further includes a processing unit, configured to:

and when the cell is switched, the cell is switched according to the second information in the special signaling.
The terminal device according to any of claims 30-32, wherein the dedicated signaling further comprises first indication information, and the first indication information is used to indicate whether the terminal device performs cell handover based on information in the system message.
The terminal device of claim 35, wherein the system message and the dedicated signaling each include second information, and wherein the second information includes at least one of the following information: t304 timer, dedicated configuration information for random access and handover condition to candidate target cell.
The terminal device according to any of claims 30-36, wherein the candidate target cells comprise a plurality of target cells, and wherein second indication information is included in the dedicated signaling, the second indication information being used to indicate the terminal device to handover to a first target cell of the plurality of target cells.
The terminal device according to claim 37, wherein the terminal device further comprises a processing unit configured to:

and switching to the first target cell according to the special signaling and/or the switching condition for switching to the first target cell included in the system information.
The terminal device according to any of claims 28-38, wherein the terminal device further comprises a receiving unit configured to:

and receiving third indication information sent by the network equipment, wherein the third indication information is used for indicating the position of the time domain resource and/or the frequency domain resource of the system message.
A terminal device according to any of claims 28-39, characterised in that the system message is a system message dedicated to carrying the first information.
The terminal device according to any of claims 28-40, wherein the system message is a system message dedicated to the NTN system.
The terminal device according to any of claims 28-41, wherein the cell in which the terminal device was located before handover is the first cell, and the terminal device further comprises a receiving unit configured to:

receiving the system message after connecting to the first cell.
A network device, comprising a transmitting unit configured to:

and sending a system message to the terminal equipment, wherein the system message comprises first information, and the first information is used for the terminal equipment to carry out cell switching.
The network device of claim 43, wherein the first information comprises at least one of: configuration information of the candidate target cell, a T304 timer, dedicated configuration information for random access and handover conditions for handover to the candidate target cell.
The network device of claim 43 or 44, wherein the sending unit is further configured to:

sending a dedicated signaling to the terminal device, where the dedicated signaling includes second information, and the second information includes at least one of the following information: identification information of the terminal device in the candidate target cell, a T304 timer, special configuration information for random access and a switching condition for switching to the candidate target cell.
The network device of claim 45, wherein the candidate target cell comprises a non-terrestrial network (NTN) cell.
The network device of claim 46, wherein the NTN cells comprise Low Earth Orbit (LEO) cells.
The network device according to any of claims 45-47, wherein the dedicated signaling comprises first indication information, and the first indication information is used to indicate whether the terminal device performs cell handover based on information in the system message.
The network device of claim 48, wherein the system message and the dedicated signaling each comprise second information, and wherein the second information comprises at least one of the following information: t304 timer, dedicated configuration information for random access and handover condition to candidate target cell.
The network device of any one of claims 45-49, wherein the candidate target cells comprise a plurality of target cells, and wherein second indication information is included in the dedicated signaling, the second indication information being used to indicate the terminal device to handover to a first target cell of the plurality of candidate cells.
The network device of any of claims 43-50, wherein the sending unit is further configured to:

and sending third indication information to the terminal equipment, wherein the third indication information is used for indicating the position of the time domain resource and/or the frequency domain resource of the system message.
The network device of any of claims 43-51, wherein the system message is a system message dedicated to carrying the first information.
The network device of any of claims 43-52, wherein the system message is a system message dedicated to an NTN system.
The network device of any of claims 43-53, wherein the sending unit is further configured to:

and after the terminal equipment is connected to the first cell, sending the system message to the terminal equipment.
A terminal device, comprising: a processor and a memory for storing a computer program, the processor being configured to invoke and execute the computer program stored in the memory to perform the method of any of claims 1 to 15.
A network device, comprising: a processor and a memory for storing a computer program, the processor being configured to invoke and execute the computer program stored in the memory to perform the method of any of claims 16 to 27.
An apparatus, comprising: a processor for calling and running a computer program from a memory to cause a device in which the apparatus is installed to perform the method of any one of claims 1 to 15.
An apparatus, comprising: a processor for invoking and running a computer program from a memory, causing an apparatus in which the apparatus is installed to perform the method of any of claims 16-27.
A computer-readable storage medium for storing a computer program which causes a computer to perform the method of any one of claims 1 to 15.
A computer-readable storage medium for storing a computer program which causes a computer to perform the method of any one of claims 16 to 27.
A computer program product comprising computer program instructions for causing a computer to perform the method of any one of claims 1 to 15.
A computer program product comprising computer program instructions for causing a computer to perform the method of any one of claims 16 to 27.
A computer program, characterized in that the computer program causes a computer to perform the method according to any of claims 1-15.
A computer program, characterized in that the computer program causes a computer to perform the method according to any of claims 16 to 27.