CN113179512B

CN113179512B - Communication method and communication device

Info

Publication number: CN113179512B
Application number: CN202110375420.8A
Authority: CN
Inventors: 强鹂; 杨林平; 范晶; 谭佳瑶; 李濛
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-07-30
Filing date: 2020-07-30
Publication date: 2022-09-09
Anticipated expiration: 2040-07-30
Also published as: CN113179512A

Abstract

A communication method and a communication apparatus are provided, which can be used in the field of communications. The method can comprise the following steps: the terminal equipment selects or reselects from a first cell to a second cell through cells, wherein the radio access technologies of the first cell and the second cell are different; the terminal equipment is in an inactive state in a first cell and reselects to a second cell through the cell; and finishing the registration process initiated by the cell reselection terminal equipment. When the terminal equipment in the inactive state performs cell reselection of different wireless technologies, a registration process or a service request process is initiated for NAS signaling connection recovery. The network device may be caused to update the information in the event that the terminal device changes radio access technology.

Description

Communication method and communication device

The present application is a divisional application of the patent application with application number 202080004626.3 entitled "a communication method and communication device".

Technical Field

The present application relates to the field of communications technologies, and in particular, to a communication method and a communication apparatus.

Background

In current communication systems, a terminal device performs cell selection or reselection based on mobility requirements. In some scenarios, the radio access technology differs between different cells. When the terminal device moves between cells of different radio access technologies, the current information of the terminal device often cannot be updated to the network device in time. This results in communication between the network device and the terminal device consuming more time and more signaling, resulting in wasted resources.

Disclosure of Invention

The application provides a communication method and a communication device, which are used for avoiding asynchronous states of network equipment sides caused by the fact that a wireless access technology is replaced by terminal equipment.

In a first aspect, a communication method is provided, including: the terminal equipment selects or reselects from a first cell to a second cell through cells, wherein the radio access technologies of the first cell and the second cell are different. The radio access technology of the first cell may be a new air interface, and the radio access technology of the second cell may be evolved universal terrestrial radio access, or the radio access technology of the first cell may be evolved universal terrestrial radio access and the radio access technology of the second cell may be a new air interface. The terminal equipment is in an inactive state in the first cell, and is selected or reselected to the second cell through the cell, so that the cell reselection terminal equipment initiates a registration process or a service request process. The terminal device may initiate a registration procedure or a service request procedure in the first cell, or the terminal device may initiate a registration procedure or a service request procedure in the second cell. Wherein, the registration flow and/or the service request flow is used for recovering the non-access stratum signaling connection. The registration flow may include an initial registration flow or a mobile and periodic registration update flow.

The embodiment of the application provides a new condition for initiating a registration procedure or a service request procedure, and when a terminal device in an inactive state performs cell selection or reselection (inter-RAT cell (re-) selection) across a radio access technology, the terminal device initiates the registration procedure or the service request procedure for NAS signaling connection recovery. The network device may be caused to update the information in the event that the terminal device changes radio access technology.

In a possible implementation manner of the first aspect, the initiating, by the terminal device, a registration procedure includes: the terminal device sends first indication information, and the first indication information is used for informing the network device to convert the terminal device into an idle state. Or the terminal device initiates a registration process including: the method comprises the steps that terminal equipment sends first indication information, and the first indication information is used for informing network equipment that the terminal equipment is in an idle state.

The network device may be a core network device or an access network device, the access network device to which the first cell belongs may be referred to as a source access network device S-RAN, and the access network device to which the second cell belongs may be referred to as a target access network device T-RAN. The S-RAN and the T-RAN may access the same core network. The core network device may be a 5G core network, the first cell and the second cell access the 5G core network device, and the exemplary core network device may be an AMF. The first indication information transmitted in the registration procedure may be transmission of the first indication information to the AMF. The terminal device is assigned a registration area in which the first cell and the second cell may be located

In the embodiment of the present application, the terminal device needs to send the state information that is currently in the idle state or the state information that is to be converted into the idle state to the network device. The registration procedure for NAS signaling connection recovery is a procedure in which the terminal device in an idle state can send information to the network device, and a request message in the registration procedure may be used to carry the first indication information. In the embodiment of the application, the terminal device may send the first indication information to the network device by initiating the registration process, and the network device may perform state transition according to the first indication information, so that the terminal device and the network device are synchronously maintained in an idle state. Therefore, the waste of air interface resources in the process of transmitting data/signaling to the terminal equipment by the network equipment is avoided, the transmission delay of downlink data/signaling is reduced, and the problems of data loss or call failure and the like caused by overlong transmission delay are avoided.

In yet another possible implementation manner of the first aspect, the terminal device sends a registration request message, where the registration request message is used to initiate a registration procedure, and the first indication information may be carried in the registration request message. When the registration process is initial registration, the registration request message is an initial registration request message. When the registration process is a mobile registration updating process, the registration request message is a mobile registration updating request message. When the registration process is a periodic update registration process, the registration request message is a periodic update registration request message. The terminal device may also send a service request message, where the service request message is used to initiate a service request procedure, and the service request message carries the first indication information. By using the service request message carrying the first indication information, the terminal device may send the first indication information to the network device in an idle state, so as to notify the network device that the terminal device is in the idle state, or notify the network device to convert the terminal device into the idle state.

In yet another possible implementation manner of the first aspect, the access stratum of the terminal device notifies the non-access stratum of the terminal device to send the first indication information. The terminal equipment comprises an access stratum and a non-access stratum. The non-access layer is a functional layer between the terminal equipment and the core network, and supports the transmission of services and signaling messages between the core network and the terminal equipment. The access stratum is the functional layer between the access network equipment and the user equipment. With respect to the access layer, a non-access layer and layers above it may be referred to as an upper layer(s). The access stratum and its layers below it may be referred to as lower layers(s) with respect to the non-access stratum.

The access stratum may receive system information of the second cell, the system information including at least one of: identification information of the second cell, identification information of a public land mobile network supported by the second cell, or radio access technology information of the second cell. And the access layer perceives that the wireless access technologies of the first cell and the second cell are different according to the system information. Since the access stratum perceives the change of the radio access technology, the terminal device can change itself into an idle state. The access stratum may instruct the non-access stratum to transmit the first indication information. The indication may be by sending indication information or a use reason value. The access layer informs the non-access layer of sending the first indication information through the reason value, and the reason value is used for indicating the reason for the terminal equipment to change the terminal equipment into the idle state to the non-access layer. The cause value may be that the radio access technologies of the first cell and the second cell are different, or the cause value may be expressed as inter-RAT cell (re-) selection performed by the terminal device. In the embodiment of the application, the access layer senses the change of the current RAT through system information, and indicates the non-access layer to send first indication information by adopting the cause value for informing the network equipment that the terminal equipment is in an idle state. The reason value notification mode is simple and easy to realize. And the non-access layer does not need to sense the RAT change by itself, and the non-access layer only needs to send the first indication information according to the notification of the access layer.

In yet another possible implementation manner of the first aspect, the access stratum of the terminal device receives system information of the second cell, where the system information of the second cell includes information of the second cell. Wherein the system information of the second cell comprises at least one of: identification information of the second cell, identification information of a public land mobile network supported by the second cell, or radio access technology information of the second cell. The access stratum of the terminal device may notify the non-access stratum of the terminal device of the reception of the information of the second cell. The terminal equipment can sense that the wireless access technology is changed according to the information of the second cell, so that the non-access layer of the terminal equipment sends the first indication information according to the information of the second cell received by the access layer of the terminal equipment. The terminal device can convert itself into an idle state, and when the terminal device converts itself into the idle state, the first indication information is used for informing the network device that the terminal device is in the idle state. Or the first indication information is used for informing the network equipment to convert the terminal equipment into an idle state.

In the embodiment of the application, the non-access stratum of the terminal device can sense the change of the RAT according to the information of the second cell, and the first indication information can be sent autonomously without the indication of the access stratum.

In yet another possible implementation manner of the first aspect, the network device may be an AMF, and the AMF may perform state synchronization according to the first indication information. The method for the network device to perform state synchronization includes two methods. In one case, when the terminal device is already in the idle state, the network device may perform the following steps for state synchronization:

the AMF deletes the locally stored terminal context information; and the AMF informs the access network equipment to delete the signaling plane connection and the user plane resource between the access network equipment and the terminal equipment. The AMF indicates that the S-RAN terminal equipment to which the first cell belongs has entered an idle state, optionally the S-RAN deletes the context information of the terminal equipment according to the indication, and the AMF informs the UPF to release the resources of the N3 interface through the SMF. N3 is the interface between the access network device and the core network device.

In another case, when the terminal device is still in the connected state, the network device may perform the following steps for state synchronization:

the AMF deletes the locally stored terminal context information; the AMF instructs the terminal equipment to release the NAS connection; and the AMF indicates that the S-RAN terminal equipment to which the first cell belongs enters an idle state, the S-RAN deletes the context information of the terminal equipment according to the indication, and the S-RAN initiates RRC connection release with the terminal equipment. If the access network equipment T-RAN to which the second cell belongs stores the context information of the terminal equipment, the AMF indicates that the T-RAN terminal equipment enters an idle state, optionally the T-RAN deletes the context information of the terminal equipment according to the indication, and/or the T-RAN initiates RRC connection release with the terminal equipment.

In the embodiment of the application, the network device performs state synchronization according to the first indication information and the current state of the terminal device. Therefore, the terminal equipment and the network equipment are simultaneously kept in an idle state, and the waste of air interface resources in the process of signaling transmission is avoided.

A second aspect provides a method of communication, comprising: the terminal equipment selects or reselects from a first cell to a second cell through cells, wherein the first cell and the second cell have different wireless access technologies. The first cell and the second cell have different radio access technologies, the radio access technology of the first cell may be a new air interface, the radio access technology of the second cell may be evolved universal terrestrial radio access, or the radio access technology of the first cell may be evolved universal terrestrial radio access, and the radio access technology of the second cell may be a new air interface. The terminal device is in an inactive state in the first cell and selects or reselects to the second cell through the cell. And finishing cell selection or reselecting the terminal equipment to send an access layer message, wherein the access layer message is used for requesting the release of the wireless resource connection. The first cell and the second cell may be in a registration area allocated by the terminal device.

In the embodiment of the application, the terminal device in the inactive state performs inter-radio access technology cell selection or reselection, the terminal device sends a radio resource connection release request message to the network device, and the network device synchronizes the terminal device and the network device to an idle state according to the received request message, so that the state synchronization of the network device and the terminal device is realized, the waste of air interface resources when the network device sends data/signaling to the terminal device is avoided, the downlink data/signaling transmission delay is reduced, and the problems of data loss or call failure and the like caused by the overlong transmission delay are avoided. In one possible implementation form of the second aspect, the access stratum message includes a cause value, and the cause value is related to the terminal device requesting the radio resource connection release. In the embodiment of the application, the access layer of the terminal device may instruct the network device to release the radio resource connection, and the instructing may be in a manner of requesting the network device to release the radio resource connection through the cause value.

In yet another possible implementation manner of the second aspect, the terminal device sends an access stratum message to an access network device to which the first cell belongs, and the access network device to which the first cell belongs performs radio resource connection release according to the access stratum message. The access network device may further notify the core network device to perform N3 resource connection release, so that the terminal device, the access network device, and the core network device are in an idle state synchronously. N3 is the interface between the access network device and the core network device. The terminal device reselecting to the second cell may refer to the terminal device selecting the second cell, but not yet camping on the second cell, and still camping on the first cell. According to the method and the device, the terminal device directly sends the access layer message to the access network device to which the first cell belongs, the access network device to which the first cell belongs directly carries out wireless resource connection release, and the core network device does not need to indicate the access network device to carry out wireless resource connection release. The first cell and the second cell can access the 5G core network equipment.

In a further possible implementation manner of the second aspect, the terminal device is camped on the second cell through cell reselection. At this time, the terminal device sends an access stratum message to the second cell. The terminal device sends an access layer message to the access network device to which the second cell belongs, and the access network device to which the second cell belongs sends a first message to the core network device, where the first message is used to request the core network device to instruct the first cell to perform radio resource connection release. The core network device sends radio resource connection release indication information to the first cell according to the received first message, and the radio resource connection release indication information is used for indicating the access network device to which the first cell belongs to carry out radio resource connection release. The embodiment of the present application provides a method for more flexibly instructing a first cell to perform radio resource connection release, so that a network device and a terminal device are synchronized in an idle state, waste of air interface resources when the network device sends data/signaling to the terminal device is avoided, transmission delay of downlink data/signaling is reduced, and problems of data loss or call failure and the like caused by too long transmission delay are avoided.

A third aspect provides a communication apparatus, where the communication apparatus in an embodiment of the present application may be a terminal device, and the communication apparatus includes: and the processing module is used for reselecting the terminal equipment from a first cell to a second cell through the cells, wherein the wireless access technologies of the first cell and the second cell are different. The radio access technology of the first cell may be a new air interface, and the radio access technology of the second cell may be evolved universal terrestrial radio access, or the radio access technology of the first cell may be evolved universal terrestrial radio access and the radio access technology of the second cell may be a new air interface. And the terminal equipment is in a radio resource control non-activated state in the first cell. The terminal equipment is in an inactive state in the first cell and reselects to the second cell through the cell. The transceiver module of the terminal device is used for sending a registration request message or a service request message, and the registration request message or the service request message is used for initiating a registration process. After completing the cell reselection, the terminal device may initiate a registration procedure or a service request procedure in the first cell, or the terminal device may also initiate a registration procedure or a service request procedure in the second cell. Wherein, the registration flow and/or the service request flow is used for non-access stratum signaling connection recovery. The registration flow may include an initial registration flow or a mobile and periodic registration update flow.

The communication device of the embodiment of the application can initiate a registration process or a service request process based on the new trigger condition. When the terminal equipment in the inactive state performs cell reselection of different wireless technologies, a registration process or a service request process is initiated for NAS signaling connection recovery. The network device may be caused to update the information in the event that the terminal device changes radio access technology.

In a possible implementation manner of the third aspect, a transceiver module of the terminal device sends first indication information in a registration procedure, where the first indication information is used to notify the network device to convert the terminal device into an idle state; or the terminal equipment is converted into an idle state, and the process of initiating the registration by the terminal equipment comprises the following steps: the terminal equipment sends first indication information, and the first indication information is used for informing the network equipment that the terminal equipment is in an idle state.

The network device may be a core network device or an access network device, and the access network to which the first cell belongs and the access network to which the second cell belongs may access the same core network. The core network device may be a 5G core network, the first cell and the second cell access the 5G core network device, and the exemplary core network device may be an AMF. The first indication information transmitted in the registration procedure may be transmission of the first indication information to the AMF. The terminal device is assigned a registration area in which the first cell and the second cell may be located.

In yet another possible implementation manner of the third aspect, the first indication information may be carried in a registration request message. When the registration process is initial registration, the registration request message is an initial registration request message. When the registration process is a mobile registration updating process, the registration request message is a mobile registration updating request message. When the registration process is a periodic update registration process, the registration request message is a periodic update registration request message. The terminal device may also send a service request message, where the service request message is used to initiate a service request procedure, and the service request message carries the first indication information. By using the service request message carrying the first indication information, the terminal device may send the first indication information to the network device in an idle state, so as to notify the network device that the terminal device is in the idle state, or notify the network device to convert the terminal device into the idle state.

In yet another possible implementation manner of the third aspect, the access stratum of the terminal device is configured to notify the non-access stratum of the terminal device to send the first indication information. The terminal equipment comprises an access stratum and a non-access stratum. The non-access layer is a functional layer between the terminal equipment and the core network, and supports the transmission of services and signaling messages between the core network and the terminal equipment. The access stratum is the functional layer between the access network equipment and the user equipment. With respect to the access layer, a layer other than the access layer and above may be referred to as an upper layer(s). The access stratum and its layers below it may be referred to as lower layers(s) with respect to the non-access stratum.

The access stratum may be configured to receive system information of the second cell, the system information including at least one of: identification information of the second cell, identification information of a public land mobile network supported by the second cell, or radio access technology information of the second cell. And the access layer perceives that the wireless access technologies of the first cell and the second cell are different according to the system information. Since the access stratum perceives the change of the radio access technology, the terminal device can change itself into an idle state. The access stratum may instruct the non-access stratum to transmit the first indication information. The indication may be by sending indication information or a use reason value. The access layer can inform the non-access layer of sending the first indication information through the reason value, and the reason value is used for indicating the reason for the terminal equipment to change the terminal equipment into an idle state to the non-access layer. The cause value may be that the radio access technologies of the first cell and the second cell are different, or the cause value may be expressed as inter-RAT cell (re-) selection performed by the terminal device.

In the embodiment of the application, the access layer senses the change of the current RAT through system information, and indicates the non-access layer to send first indication information by adopting the cause value for informing the network equipment that the terminal equipment is in an idle state. The reason value notification mode is simple and easy to realize. And the non-access layer does not need to sense the RAT change by itself, and the non-access layer only needs to send the first indication information according to the notification of the access layer.

In yet another possible implementation manner of the third aspect, the access stratum of the terminal device may be configured to receive system information of the second cell, where the system information of the second cell includes information of the second cell. Wherein the system information of the second cell comprises at least one of: identification information of the second cell, identification information of a public land mobile network supported by the second cell, or radio access technology information of the second cell. The access stratum of the terminal device may be configured to notify the non-access stratum of the terminal device of the reception of the information of the second cell. The terminal device can sense that the wireless access technology is changed according to the information of the second cell, so that the non-access layer of the terminal device sends the first indication information according to the information of the second cell received from the access layer of the terminal device. The terminal device can convert the terminal device into an idle state, and when the terminal device converts the terminal device into the idle state, the first indication information is used for informing the network device that the terminal device is in the idle state. Or the first indication information is used for informing the network equipment to convert the terminal equipment into an idle state.

In the embodiment of the application, the non-access stratum of the terminal device is used for sensing that the RAT is changed according to the information of the second cell, and the first indication information can be sent autonomously without the indication of the access stratum.

In yet another possible implementation manner of the third aspect, the network device may be an AMF, and the AMF may perform state synchronization according to the first indication information. The method for the network device to perform state synchronization includes two methods. In one case, when the terminal device is already in the idle state, the network device may perform the following steps for state synchronization:

and the AMF deletes the terminal context information locally stored by itself. And the AMF informs the access network equipment to release the signaling plane connection and the user plane resource between the access network equipment and the terminal equipment. And the AMF indicates that the S-RAN terminal equipment to which the first cell belongs enters an idle state, and the S-RAN deletes the context information of the terminal equipment according to the indication. The AMF informs the UPF to release the resources of the N3 interface through the SMF.

and the AMF deletes the locally stored terminal context information. The AMF informs the S-RAN to release the signaling plane connection and user plane resources. The AMF instructs the terminal device to release the NAS connection. The AMF indicates that the S-RAN terminal equipment to which the first cell belongs enters an idle state. And the S-RAN deletes the context information of the terminal equipment according to the indication. The S-RAN initiates RRC connection release with the terminal device. If the T-RAN of the access network equipment to which the second cell belongs stores the context information of the terminal equipment, the AMF indicates that the T-RAN terminal equipment enters an idle state, optionally the T-RAN deletes the context information of the terminal equipment according to the indication, and/or the T-RAN initiates RRC connection release with the terminal equipment, and/or the T-RAN initiates user plane resource release with the terminal equipment.

In the embodiment of the application, the network device performs state synchronization according to the first indication information and the current state of the terminal device. Therefore, the terminal equipment and the network equipment are simultaneously kept in an idle state, and the waste of air interface total resources in the process of signaling transmission is avoided.

A fourth aspect provides a communication apparatus, which may be a terminal device, including: the processing module is used for reselecting the communication device from a first cell to a second cell through the cell, wherein the wireless access technologies of the first cell and the second cell are different. The first cell and the second cell have different radio access technologies, the radio access technology of the first cell may be a new air interface, the radio access technology of the second cell may be evolved universal land-based radio access, or the radio access technology of the first cell may be evolved universal land-based radio access, and the radio access technology of the second cell may be a new air interface. The terminal equipment is in an inactive state in the first cell and reselects to the second cell through the cell. The communication device further comprises a transceiver module for transmitting an access stratum message, wherein the access stratum message is used for requesting the release of the radio resource connection. The first cell and the second cell may be in a registration area allocated by the terminal device.

In the embodiment of the application, the terminal device in the inactive state performs inter-radio access technology cell reselection, the terminal device sends a radio resource connection release request message to the network device, and the network device synchronizes the terminal device and the network device to an idle state according to the received request message, so that the state synchronization of the network device and the terminal device is realized, the waste of idle resources when the network device sends data/signaling to the terminal device is avoided, the downlink data/signaling transmission delay is reduced, and the problems of data loss or call failure and the like caused by the overlong transmission delay are avoided.

In a possible implementation manner of the fourth aspect, the access stratum may instruct the network device to release the radio resource connection, and the instruction may be a cause value, where the cause value is related to the terminal device requesting the radio resource connection release. According to the method and the device, the access layer of the terminal equipment can request the wireless resource connection release of the network equipment through the reason value, and the indication mode is simple and easy to realize.

In yet another possible implementation manner of the fourth aspect, the transceiver module of the terminal device is configured to send an access stratum message to the access network device to which the first cell belongs, and the access network device to which the first cell belongs performs radio resource connection release according to the access stratum message. The access network device may further notify the core network device to perform N3 resource connection release, so that the terminal device, the access network device, and the core network device are in an idle state synchronously. N3 is an interface between an access network device and a core network device. The terminal device reselecting to the second cell may refer to that the terminal device selects the second cell, but does not yet camp on the second cell, and still camps on the first cell. According to the method and the device, the terminal device directly sends the access layer message to the access network device to which the first cell belongs, the access network device to which the first cell belongs directly carries out wireless resource connection release, and the core network device does not need to indicate the access network device to carry out wireless resource connection release. The first cell and the second cell can access the 5G core network equipment.

In yet another possible implementation manner of the fourth aspect, the terminal device reselects to camp on the second cell through the cell. At this time, the transceiver module of the terminal device is configured to send an access stratum message to the second cell. The terminal device sends an access layer message to the access network device to which the second cell belongs, and the access network device to which the second cell belongs sends a first message to the core network device, where the first message is used to request the core network device to instruct the first cell to perform radio resource connection release. And the core network equipment sends wireless resource connection release indication information to the first cell according to the received first message, and is used for indicating the access network equipment to which the first cell belongs to carry out wireless resource connection release. The embodiment of the application provides a method for more flexibly indicating a first cell to perform wireless resource connection release, so that a network device and a terminal device are in an idle state synchronously, idle resource waste when the network device sends data/signaling to the terminal device is avoided, downlink data/signaling transmission delay is reduced, and problems of data loss or call failure and the like caused by overlong transmission delay are avoided.

A fifth aspect provides a communications apparatus that includes a transceiver to execute instructions for receiving and transmitting information and a processor to perform other steps. In particular, the communication device is configured to perform the method of any of the possible implementations of the first aspect.

A sixth aspect provides a communications apparatus that includes a transceiver to execute instructions for receiving and transmitting information and a processor to perform other steps. In particular, the communication device is configured to perform the method of any possible implementation of the second aspect.

A seventh aspect provides a computer readable storage medium having stored thereon a computer program for execution by a processor to perform the method of any of the possible implementations of the first aspect.

An eighth aspect provides a computer readable storage medium having stored thereon a computer program for execution by a processor to perform a method in any of the possible implementations of the second aspect.

A ninth aspect provides a terminal device comprising a memory for storing instructions and a processor for executing the instructions stored by the memory, and execution of the instructions stored in the memory causes the processor to perform the method of any possible implementation of the first aspect.

A tenth aspect provides a network device comprising a memory for storing instructions and a processor for executing the instructions stored by the memory, and execution of the instructions stored in the memory causes the processor to perform the method of any possible implementation of the second aspect.

An eleventh aspect provides a communication system comprising the communication apparatus of the third aspect.

A twelfth aspect provides a communication system comprising the communication apparatus of the fourth aspect.

A thirteenth aspect provides a computer program product comprising instructions for storing a computer program which, when run on a computer, causes the computer to perform the method of any of the possible implementations of the first aspect described above.

A fourteenth aspect provides a computer program product comprising instructions for storing a computer program which, when run on a computer, causes the computer to perform the method of any possible implementation of the second aspect described above.

Drawings

Fig. 1 is a schematic diagram of a communication system suitable for use in the communication method of the embodiment of the present application;

fig. 2 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 3 is a schematic diagram of an alternative application scenario provided in an embodiment of the present application;

fig. 4 is a flowchart of another communication method provided in an embodiment of the present application;

fig. 5 is a schematic diagram of a communication method according to an embodiment of the present application;

fig. 6 is a flowchart of a communication method according to a second embodiment of the present application;

fig. 7 is a flowchart of a communication method according to a third embodiment of the present application;

fig. 8 is a flowchart of another communication method provided in the third 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 a communication device according to an embodiment of the present application;

fig. 11 is a schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

Hereinafter, some terms in the embodiments of the present application are explained so as to be easily understood by those skilled in the art.

1. The terminal equipment comprises equipment for providing voice for users, equipment for providing data connectivity for users and equipment for providing voice and data connectivity for users. For example, may include a handheld device having wireless connection capability, or a processing device connected to a wireless modem. Or simply terminal. The terminal may communicate with a core network via a Radio Access Network (RAN), exchange voice or data with the RAN, or interact with the RAN. The terminal may include a User Equipment (UE), a wireless terminal, a mobile terminal, a device-to-device communication (D2D) terminal, a vehicle-to-all (V2X) terminal, a machine-to-machine/machine-type communication (M2M/MTC) terminal, an internet of things (IoT) terminal, a subscriber unit (subscriber unit), a subscriber station (subscriber state), a mobile station (mobile state), a remote station (remote state), an access point (access point, AP), a remote terminal (remote terminal), an access terminal (access terminal), a user terminal (user terminal), a user agent (user agent), or a user equipment (user device), etc. May include mobile telephones (or so-called "cellular" telephones), computers with mobile terminals, portable, pocket, hand-held, computer-embedded mobile devices, and the like. May include Personal Communication Service (PCS) phones, cordless phones, Session Initiation Protocol (SIP) phones, Wireless Local Loop (WLL) stations, Personal Digital Assistants (PDAs), and the like. But also limited devices, devices with lower power consumption, or devices with limited storage capacity, or devices with limited computing capacity, etc. Information sensing devices may include bar codes, Radio Frequency Identification (RFID), sensors, Global Positioning Systems (GPS), laser scanners, and the like.

By way of example and not limitation, in the embodiments of the present application, the terminal may also be a wearable device. Wearable equipment can also be called wearable smart device or intelligent wearable equipment etc. is the general term of using wearable technique to carry out intelligent design, develop the equipment that can dress to daily wearing, like glasses, gloves, wrist-watch, dress and shoes etc.. A wearable device is a portable device that is worn directly on the body or integrated into the clothing or accessories of the user. The wearable device is not only a hardware device, but also realizes powerful functions through software support, data interaction and cloud interaction. The generalized wearable smart device includes full functionality, large size, and can implement full or partial functionality without relying on a smart phone, such as: smart watches or smart glasses and the like, and only focus on a certain type of application functions, and need to be used in cooperation with other devices such as smart phones, such as various smart bracelets, smart helmets, smart jewelry and the like for monitoring physical signs.

While the various terminals described above, if located on a vehicle, e.g. placed in or mounted in a vehicle, may be considered as vehicle mounted terminals, e.g. also referred to as on-board units (OBUs).

In the embodiment of the present application, the apparatus for implementing the function of the terminal may be the terminal, or may be a circuit capable of supporting the terminal to implement the function, for example, a circuit that can be applied to a system-on-chip, and the system-on-chip may be installed in the terminal. In the embodiment of the present application, the chip system may be composed of a chip, and may also include a chip and other discrete devices. In the technical solution provided in the embodiment of the present application, a device for implementing a function of a terminal is taken as an example, and the technical solution provided in the embodiment of the present application is described.

2. The network device may include a Radio Access Network (RAN) device, such as a base station (e.g., an access point). It may refer to a device in the access network that communicates with the terminal device through an air interface, or a network device in a vehicle-to-all (V2X) technology is a Road Side Unit (RSU). The base station may be configured to interconvert received air frames and IP packets as a router between the terminal and the rest of the access network, which may include an IP network. The RSU may be a fixed infrastructure entity supporting the V2X application, exchanging messages with other entities supporting the V2X application. The network device may also coordinate attribute management for the air interface. For example, the network device may include an evolved Node B (NodeB or eNB or e-NodeB) in a Long Term Evolution (LTE) system or a long term evolution-advanced (LTE-a) system, or may also include an Evolved Packet Core (EPC), a fifth generation communication technology (5G), a next generation Node B (gNB) in a new radio, NR, system (also referred to as NR system) or include a Centralized Unit (CU) and a Distributed Unit (DU) in a Cloud access network (Cloud radio access network, Cloud RAN) system, which is not limited in this embodiment.

The network device may also include a core network device including, for example, an access and mobility management function (AMF) or the like.

3. Status of terminal device

3.1 RRC Idle State (RRC _ IDLE)

The idle state refers to a state in which the terminal device resides in a cell but the terminal device is not in a random access procedure. The terminal device typically enters an idle state after power-on, or after RRC release.

3.2 RRC CONNECTED State (RRC _ CONNECTED)

The connected state refers to a state where the terminal device is in a state where the RRC release is not performed after the terminal device completes the random access procedure. The terminal equipment can carry out data transmission with the network equipment in a connected state.

When the terminal device is in an idle state, after the terminal device completes a random access process, the state of the terminal device is changed to a connected state.

3.3 RRC Inactive State (RRC _ INACTIVE)

The inactive state is a state between a connected state and an idle state, and the terminal device in the inactive state maintains a suspended user plane bearer (suspend) of an air interface and a user plane bearer and a control plane bearer (cs bearer) between a Radio Access Network (RAN) and a Core Network (CN). When a terminal device initiates a call or service request, it needs to activate the user plane bearer of the air interface, and reuse the user plane bearer and control plane bearer between the existing RAN-CNs.

4. Cell reselection (Cell Re-Selection)

The network is deployed in individual cells, each cell having its own coverage area. The terminal device will move frequently during the use process, and if the terminal device moves out of the coverage area of the current serving cell and enters a new cell, the terminal device will reselect to reside in the new cell to continue to obtain the service. This is typically done in two ways, and cell reselection may be performed for terminal devices in the idle or inactive state. For the connected terminal device, a switching mode can be used, which is a network side dominant mode, and the terminal device switches to the designated cell according to the instruction issued by the network.

The process of cell reselection can be divided into the following steps:

1) measurement of cell reselection.

The current service cell and the adjacent cells (including cells of same frequency, different frequency and different systems) are measured. The neighbor measurement takes into account two parameters: cell priority, signal quality of the currently camped cell.

2) And judging whether the signals of the adjacent cells meet reselection standards. After the measurement is completed, the cell quality is judged.

3) If yes, starting reselection and receiving the system message of the new cell.

And after the adjacent cells are measured and the cells meeting the residence conditions are determined to exist, trying to reside in a new cell. If not, the current serving cell is remained.

The process of the terminal device trying to camp on the new cell is as follows: searching a target cell, receiving a system message on a new cell after the target cell is searched, and judging whether the new cell can normally reside, for example, judging through the system message of the new cell. And after the system message is received, the terminal equipment resides in a new cell. The terminal device has now reselected to a new cell.

5. Paging (Paging)

The network device may notify the terminal device in the RRC IDLE state (RRC _ IDLE) or the RRC INACTIVE state (RRC _ INACTIVE) to receive a paging message (paging message) through paging, or the network may transmit a short message (short message) to the terminal device in the RRC IDLE state (RRC _ IDLE), the RRC INACTIVE state (RRC _ INACTIVE) or the RRC CONNECTED state (RRC _ CONNECTED) through paging to indicate System Information (SI) update or Tsunami Warning/Commercial Mobile Alert (ETWS/CAMS, easy and Tsunami Warning System/Commercial Mobile Alert Service).

6. Non-Access Stratum signaling Connection Recovery flow (Non-Access Stratum Signalling Connection Recovery, NAS Signalling Connection Recovery)

NAS signaling Connection (NAS signaling Connection) is a signaling Connection between a terminal device And an Access And Mobility Management Function (AMF) through an N1 interface, And is used for NAS signaling exchange between the terminal device And a core network.

The NAS signaling Connection between the terminal device and the AMF may be reflected in two Connection Management States (CMs).

1) Connection management state IDLE (CM-IDLE)

When the terminal equipment is in the CM-IDLE state, no NAS signaling connection exists between the terminal equipment and the AMF.

2) Connection management status connection status (CM-CONNECTED)

When the terminal equipment is in the CM-CONNECTED state, NAS signaling connection through an N1 interface exists between the terminal equipment and the AMF. The terminal equipment keeps RRC connection with a 5G Access Network (NG-RAN) and keeps connection between the Access Network and the AMF, and the terminal equipment is used for 3GPP Access.

The NAS signaling connection recovery procedure is a mechanism initiated by the NAS layer to recover NAS signaling connection when the lower layer indicates "RRC connection failure". The NAS signaling connection recovery procedure may be used by initiating an initial registration procedure, a mobility and a periodic registration update.

7. RAN-based Notification Area (RNA)

RNA is a concept related to RRC _ INACTIVE state, and may cover one cell or multiple cells, but the RNA must be within a registration area configured in a core network, and when an RNA timer of a terminal device expires or the terminal device moves out of an RNA range, the terminal device initiates an RNA update (RANU) procedure.

8. Radio Access Technology (RAT)

The radio access technology, also known as the air interface, is a key issue for wireless communications. It is used to connect the user terminal with the network node through the wireless medium to realize the information transmission between the user and the network. The signals transmitted by the radio channel should follow certain protocols, which constitute the main content of the radio access technology.

The Radio Access technology for the 5G system may include a New Radio (NR), an Evolved Universal Terrestrial Radio Access (E-UTRA), and the like. Common wireless Access technologies of the 4G system may include Long Term Evolution (LTE) technology, Terrestrial Radio Access (UTRA) technology, and the like.

9. Access network Release process (AN Release)

The AN Release procedure is adapted to Release the logical (NG-AP) signaling connection and the associated N3 user plane connection, as well as RAN RRC signaling and resources. The AN Release flow may be initiated by the (R) AN or by the AMF.

The first situation is as follows: RAN-initiated, may include the following steps:

step 1: if there are some confirmed RAN conditions, for example: radio Link Failure (Radio Link Failure), or other RAN internal reasons, the RAN may decide to initiate the terminal device context release in the RAN. In this case, the RAN sends a Context Release Request message (N2 UE Context Release Request) message to the AMF. The purpose of the terminal device context release request procedure is to enable the NG-RAN node to request the AMF to release the logical NG connection associated with the terminal device. The process uses terminal device related signaling.

Step 2: the AMF sends Context Release indication information (N2 UE Context Release Command) to instruct the RAN to Release the terminal device Context.

And step 3: the RAN requests the terminal device to release the RAN connection if the RRC connection between the RAN and the terminal device is not released. The context of the terminal device is deleted once the RAN receives a RAN connection release acknowledgement from the terminal device.

And 4, step 4: the RAN returns a Release Complete message (UE Context Release Complete) to the AMF, carrying the relevant session list.

And 5: the AMF instructs the SMF to notify the UPF to release the interface resources of N3.

Case two: AMF initiation, which may include the following steps:

step 1: due to internal AMF events, including: receiving a service request or a registration request to establish another NAS signaling connection still via the NG-RAN, the AMF sends context release indication information.

After step 1, steps 3 to 5 in the RAN initiation are continued.

10. The technical scheme of the embodiment of the application can be applied to various communication systems, for example: a fifth Generation (5G) system, such as NR, and future communication systems, such as 6G systems, etc.

This application is intended to present various aspects, embodiments or features around a system that may include a number of devices, components, modules, and the like. It is to be understood and appreciated that the various systems may include additional devices, components, modules, etc. and/or may not include all of the devices, components, modules etc. discussed in connection with the figures. Furthermore, a combination of these schemes may also be used.

The network architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not form a limitation on the technical solution provided in the embodiment of the present application, and as a person of ordinary skill in the art knows that along with the evolution of the network architecture and the appearance of a new service scenario, the technical solution provided in the embodiment of the present application is also applicable to similar technical problems.

For the convenience of understanding the embodiments of the present application, a communication system applicable to the embodiments of the present application will be first described in detail by taking the communication system shown in fig. 1 as an example. Fig. 1 shows a schematic diagram of a communication system suitable for the communication method of the embodiment of the present application. As shown in fig. 1, the communication system 100 includes a network device 102 and a terminal device 106, where the network device 102 may be configured with multiple antennas and the terminal device may also be configured with multiple antennas. Optionally, the communication system may further include the network device 104, and the network device 104 may also be configured with multiple antennas. Fig. 1 is a simplified schematic diagram of an example for ease of understanding only, and other network devices or other terminal devices, not shown in fig. 1, may also be included in the communication system.

Network device 102 or network device 104 may also include a number of components related to signal transmission and reception. Such as a processor, modulator, multiplexer, demodulator, demultiplexer, or the like.

In the communication system 100, the network device 102 and the network device 104 may each communicate with a plurality of terminal devices, such as the terminal device 106 shown in the figure. It should be understood that the terminal device communicating with network device 102 and the terminal device communicating with network device 104 may be the same or different. Terminal device 106 shown in fig. 1 may communicate with both network device 102 and network device 104. This is merely illustrative of one possible scenario in which a terminal device may only communicate with network device 102 or network device 104, and is not intended to be limiting.

The following describes embodiments of the present application in detail with reference to the drawings.

First, a registration procedure related to the embodiment of the present application is described, where a terminal device needs to register in a network through the registration procedure to be authorized to obtain a relevant service, including: mobility tracking and reachability. The registration process is a general term of initial registration, mobility and periodic registration update, and the registration process is used for NAS signaling connection recovery.

First, Initial Registration (Initial Registration)

The initial registration is the first registration initiated by the terminal device, and the initial registration process may be used for the terminal device to perform initial registration of a 5G system (5G system, 5GS) service. When the terminal device initiates initial registration, the terminal device may indicate "initial registration" in an Information Element (IE) of the 5G registration type. The terminal device may initiate an initial registration procedure by sending a registration request message to the AMF. Reasons for initiating the initial registration procedure may include the following:

a) when the terminal equipment carries out 5GS service to carry out initial registration;

b) when the terminal equipment carries out emergency service to carry out initial registration;

c) and when the terminal equipment carries out the short message service based on the NAS so as to carry out initial registration.

Second, Mobility and Periodic Registration Update (Registration Procedure for Mobility and Periodic Registration Update)

The flow is used for the terminal equipment to carry out mobility and periodic registration updating of the 5GS service. The process is used for periodic registration update of 5GS service, and is only executed when 3GPP is accessed.

The terminal device may initiate the mobility and periodic registration update procedures by sending a registration request message to the AMF. The mobile and periodic registration update can be divided into a mobile registration update flow and a periodic registration update flow.

The mobile registration update occurs when the terminal device moves from one place to another and a Tracking Area (TA) changes. The result of the mobile registration update is an update of the TA and related parameters.

For periodic registration update, after the terminal device connects to the network, the network initiates a registration request at periodic timer intervals to determine whether the user still exists.

The reasons for initiating mobile and periodic registration updates are also included, for example, when the end device detects entry into a tracking area and is not in the tracking area list previously registered by the end device in the AMF. Or in 5GMM-IDLE mode, when a periodic registration update timer times out, etc.

An embodiment of the present application provides a new method for initiating a registration procedure, and fig. 2 is a flowchart of a communication method provided in an embodiment of the present application, and with reference to fig. 2, the method includes:

201: a terminal device selects or reselects from a first cell to a second cell through cells, wherein the first cell and the second cell have different radio access technologies, and the terminal device is in an inactive state in the first cell;

202: the terminal equipment initiates a registration process.

In 201, the terminal device is in an inactive state in the first cell, where the inactive state may refer to a radio resource control inactive state. The inactive state is a state in which: the terminal device remains in the CM-CONNECTED state and the terminal device can move within the RNA region without notifying the NG-RAN. When the terminal device is in the inactive state, the last service access network will retain the context of the terminal device, and the AMF associated with the terminal device and the User Plane Function (UPF) remain connected. When the terminal equipment is seen from the core network, the terminal equipment is in a connected state. When the terminal equipment is in RRC _ INACTIVE, if the last service access network receives the downlink data from UPF or the downlink signaling from AMF, the access network pages the terminal equipment in all cells of RNA, if the cells of RNA belong to adjacent access networks, the access network sends paging information to the corresponding adjacent access nodes through an Xn port. Here, the inactive state may refer to an RRC inactive state, or may be referred to as an RRC inactive instruction in 5G system Mobility Management Connected Mode (5GS Mobility Management Connected Mode with RRC inactive indication).

In the embodiment of the present application, RATs of the first cell and the second cell may be different. Illustratively, the RAT of the first cell may be NR and the RAT of the second cell may be E-UTRA. Or the RAT of the first cell may be E-UTRA and the RAT of the second cell may be NR. Or the RAT of the first cell may be E-UTRA and the RAT of the second cell may be LTE. Or the RAT of the first cell may be NR and the RAT of the second cell may be UTRA. Or the RAT of the first cell may be UTRA and the RAT of the second cell may be NR. Or the first cell may be a 5G RAT and the second cell a 4G RAT. It should be noted that this is merely exemplary.

In this embodiment, the terminal device may refer to from the first cell to the second cell through cell selection or reselection: the terminal equipment performs cell measurement on the first cell, and selects the second cell as a new cell but does not reside. Or, after selecting the second cell as the new cell, the terminal device receives the system information of the second cell, and determines that the second cell can normally camp. Or the terminal equipment determines that the second cell can normally reside and then resides in the second cell. All three cases above can be understood as the terminal device reselecting from a first cell to a second cell through a cell.

In 201, the terminal device may reselect from the first cell to the second cell, and due to the difference between RATs of the first cell and the second cell, the cell reselection at this time may also be referred to as inter-RAT cell reselection (inter-RAT cell re-selection) or inter-RAT cell selection (inter-RAT cell selection). Or that inter-RAT mobility occurred for the UE.

In the embodiment of the present application, when the terminal device in the inactive state performs inter-RAT cell (re-) selection, 202 is further performed.

In 202, the terminal device initiates a registration procedure or a service request procedure (service request procedure) for NAS signaling connection recovery. The registration process includes initial registration, mobile registration update or periodic registration update.

The embodiment of the application provides a new condition for initiating a registration process, and when a terminal device in an inactive state performs inter-RAT cell (re-) selection, the registration process is initiated for NAS signaling connection recovery, so that network devices update information according to different RATs.

Fig. 3 is a schematic diagram of an optional application scenario provided in an embodiment of the present application, and fig. 4 is a flowchart of another communication method provided in the embodiment of the present application, and the another communication method provided in the embodiment of the present application is described with reference to the optional application scenario shown in fig. 3. The method comprises the following steps:

401: the terminal equipment is selected or reselected from a first cell to a second cell through the cells, the wireless access technologies of the first cell and the second cell are different, and the terminal equipment is in an inactive state in the first cell.

In 401, the meaning of the inactive state and the cell reselection is the same as 201, and is not described herein again. Step 401 is described below in conjunction with the application scenario of fig. 3.

The terminal device needs to register with the network device in order to communicate with the network device. When the terminal device registers to the network device, the network device allocates a Registration Area (RA) to the terminal device. The registration Area may also be referred to as a Tracking Area identity list (TAI list), and when the terminal device is about to leave the RA, a mobile registration procedure is initiated to notify the network device of the current location information of the terminal device. The network device may assign a new RA to the terminal device. When the network has downlink data or signaling to be sent to the terminal device, the network pages the terminal device in the RA range. The network device does not consider the difference of RATs when allocating the RA to the terminal device, i.e. there may be multiple RATs within 1 RA.

As shown in fig. 3, the RA range allocated to the terminal device shown in fig. 3 includes a first cell and a second cell, and RATs of the first cell and the second cell are different. Illustratively, the RAT of the first cell may be NR and the RAT of the second cell may be E-UTRA. Or the RAT of the first cell may be E-UTRA and the RAT of the second cell may be NR. Or the RAT of the first cell may be E-UTRA and the RAT of the second cell may be LTE. Or the RAT of the first cell may be NR and the RAT of the second cell may be UTRA. Or the RAT of the first cell may be UTRA and the RAT of the second cell may be NR. It should be noted that this is merely exemplary.

The Access Network to which the first cell belongs may be referred to as a Source Radio Access Network (S-RAN), and the Access Network to which the second cell belongs may be referred to as a Target Radio Access Network (T-RAN). In fig. 3, the S-RAN and the T-RAN may access the same core network, or may be referred to as the first cell and the second cell being connected to the same core network device. For example, the S-RAN and the T-RAN are connected to the same AMF.

In this embodiment, the core network device and the access network device may be collectively referred to as a network device. Here, the core network device is also only illustrated by an AMF, and the core network device in this embodiment may be a 5G core network, and the core network device includes but is not limited to: AMF, User Plane Function (UPF), Authentication service Function (AUSF), Data Network (DN), Unstructured Data Storage Function (UDFS), Network service presentation Function (NEF), Network element Data Repository Function (NF), Network Slice Selection Function (NSSF), Policy Control Function (PCF), process Management Function (SMF), Unified Data Management Function (UDM), Unified Data Repository Function (UDR), or Application layer Function (AF).

The technical scheme provided by the embodiment of the application can be applied to fifth generation, sixth generation and future mobile communication systems. When the technical solution provided in the embodiment of the present application is applicable to a sixth generation and future mobile communication systems, the corresponding network device and terminal device may be devices applicable to the sixth generation and future mobile communication systems.

The terminal device is in an inactive state in the first cell, and if the terminal device passes through an inter-RAT cell (re-) selection to the second cell, the terminal device is changed to an idle state. Here, the Idle state may refer to an RRC Idle state, or may be referred to as a 5G system Mobility Management Idle Mode (5GS Mobility Management Idle Mode, 5GMM-Idle Mode).

402: the terminal equipment initiates a registration process, wherein the initiation of the registration process comprises the following steps: the terminal equipment sends first indication information, wherein the first indication information is used for informing the network equipment that the terminal equipment is in an idle state or informing the network equipment that the terminal equipment is converted into the idle state.

At 402, the terminal device in the inactive state reselects to the second cell with a different RAT and then transitions to the idle state, at this time, the terminal device may send first indication information to the network device in the registration procedure, where the first indication information is used to notify the network device that the terminal device is already in the idle state, or notify the network device to transition the terminal device to the idle state.

In 402, a flow is registered for NAS signaling connection recovery. The registration process includes initial registration, mobile registration update or periodic registration update. The terminal device will change to the idle state when performing inter-RAT cell (re-) selection, and in this embodiment of the present application, the terminal device may send the state information that is currently in the idle state or the state information that is to be changed to the idle state to the network device. The registration procedure for NAS signaling connection recovery is a procedure in which the terminal device in an idle state can send information to the network device, and a request message in the registration procedure may be used to carry the first indication information. In the embodiment of the application, the terminal device may send the first indication information to the network device by initiating the registration process, and the network device may perform state transition according to the first indication information, so that the terminal device and the network device are synchronously maintained in an idle state. Therefore, the waste of air interface resources in the process of transmitting data/signaling to the terminal equipment by the network equipment is avoided, the transmission delay of downlink data/signaling is reduced, and the problems of data loss or call failure and the like caused by overlong transmission delay are avoided.

How to avoid wasting air interface resources in the process of transmitting data/signaling in the embodiment of the present application will be described below:

when the terminal device is changed into or needs to be changed into an idle state, if the network device cannot update the state synchronously, the state information of the terminal device and the state information of the network device are inconsistent. At this time, the process of the network device transmitting the downlink data/signaling to the terminal device is as follows: the AMF sends the data/signaling to the Access Network device, and the Access Network device performs RAN Paging (Radio Access Network Paging) in the RNA range, which results in RAN Paging failure due to inconsistency between the state information of the terminal device and the Network device. The access network equipment reports the Paging failure result to the AMF, the AMF further carries out Core network Paging (Core Net Paging, CN Paging) in the range of the registration area, and when the CN Paging is successful, the AMF sends the data to the terminal equipment. The inconsistency of the state information of the terminal device and the network device may cause that it takes a long time for the downlink data/signaling to be transmitted to the terminal device, and waste the paging signaling and the air interface resource.

If the AMF can timely know the change of the connection state of the terminal equipment, when the AMF transmits downlink data/signaling to the terminal equipment, the AMF can directly carry out CN Paging in the range of the registration area, and when the CN Paging is successful, the AMF sends the data to the terminal equipment.

In the embodiment of the application, when the terminal device performs an inter-RAT cell (re-) selection, the terminal device will be changed to an idle state. The terminal device sends first indication information to the network device through a registration process for indicating that the connection state is about to change or has changed. The network device can perform state transition according to the first indication information, so that the terminal device and the network device synchronously keep an idle state. Therefore, the waste of air interface resources in the process of transmitting data/signaling to the terminal equipment by the network equipment is avoided, the transmission delay of downlink data/signaling is reduced, and the problems of data loss or call failure and the like caused by overlong transmission delay are avoided.

In the embodiment of the present application, as an optional implementation manner, a Service Request procedure (Service Request procedure) may be used instead of the registration procedure. The service request procedure may also be used for NAS signaling connection recovery, and the service request procedure may send a service request message, where the first indication information may be carried in the service request message. In the embodiment of the present application, only the registration process may be replaced by the service request process, and the remaining steps are completely the same and applicable.

Fig. 2 to fig. 4 are general descriptions of technical solutions provided in the embodiments of the present application, and the technical solutions in the embodiments of the present application will be described in detail below with reference to a first embodiment to a third embodiment, where the first embodiment to the third embodiment are based on the ideas of the technical solutions in fig. 2 to fig. 4, and the contents described in fig. 2 to fig. 4 are applicable to the first embodiment to the third embodiment of the present application.

Example one

In the first embodiment of the present application, a terminal device is in an inactive state in a first cell, and goes from the first cell to a second cell through cell selection or reselection, an Access Stratum (AS) of the terminal device receives system information of the second cell, where the system information of the second cell includes RAT information of the second cell. The AS layer reports the system information to a Non-Access Stratum (NAS) of the terminal equipment. At this time, the terminal device knows that inter-RAT cell (re-) selection occurs through the system information of the second cell, that is, RATs of the first cell and the second cell are different. The terminal device executes a registration process, and notifies the network device in the registration process that the state of the terminal device is changed into an idle state at the moment, or notifies the network device to change the state of the terminal device into the idle state.

Fig. 5 is a schematic diagram of a communication method according to an embodiment of the present application, where in fig. 5, a terminal device includes an AS layer and an NAS layer, a T-RAN refers to an access network device to which a second cell belongs, and an AMF is a core network device to which the access network devices of the first cell and the second cell are connected. As shown in fig. 5, the method includes:

501: the terminal equipment is selected or reselected from a first cell to a second cell through the cell, the RAT of the first cell is different from that of the second cell, and the terminal equipment is in an inactive state in the first cell.

501 is the same as 201 or 401 and will not be described further herein.

502: the terminal device receives system information of the second cell.

The terminal device receives system information of the second cell. The terminal device may receive the system information before camping on the second cell or after camping on the second cell. The system information of the second cell may include: identification information of the second cell, identification information of a public land mobile network supported by the second cell, or radio access technology information of the second cell.

In 502, it may be the AS layer of the terminal device that receives the system information, the AS layer being a functional layer between the access network device and the user equipment. The AS layer is responsible for transporting data over the radio connection and managing radio resources. The AS layer of the terminal device may include: a Physical Layer (PHY), a Media Access Control (MAC), a Radio Link Control (RLC), a Packet Data Convergence Protocol (PDCP), and a Radio Resource Control (RRC).

Structures other than the AS layer may be referred to AS a NAS layer, which is a functional layer between the terminal device and the core network. The NAS supports the transmission of traffic and signaling messages between the core network and the terminal devices.

Illustratively, the NAS layer and layers above it may be referred to AS upper layers (upperlayers) with respect to the AS layer. The AS layer and its following layers may be referred to AS lower layers (lower layers) with respect to the NAS layer.

503: and the NAS layer of the terminal equipment sends the first indication information according to the information of the second cell received by the AS layer.

And the AS layer acquires the related information of the second cell through the system information of the second cell, wherein the related information comprises RAT information of the second cell. And the AS layer informs the NAS layer of the information of the second cell. The NAS layer perceives that the RAT is changed according to information of the second cell. The NAS layer also knows at this time that the terminal device is still inactive at this time and is located within the registration area.

504: the terminal device transitions itself to an idle state.

504 is an optional step in the first embodiment of the present application, where the NAS layer senses that the RAT changes according to the information of the second cell, and the terminal device enters an idle state according to a protocol specification. The terminal device may transition itself to the idle state, or may notify the network device to transition the terminal device to the idle state in subsequent steps.

In 504, the terminal device may delete its internal context information, thereby transitioning the connected state to an idle state.

505: the terminal equipment initiates a registration process or a service request process.

In 505, the terminal device may send a registration request message, where the registration request message is used to initiate a registration procedure. When the registration process is initial registration, the registration request message is an initial registration request message. When the registration process is a mobile registration updating process, the registration request message is a mobile registration updating request message. When the registration process is a periodic update registration process, the registration request message is a periodic update registration request message. The terminal device may send a service request message, where the service request message is used to initiate a service request procedure.

The registration request message or the service request message sent by the terminal equipment comprises first indication information. When the terminal device executes 504, the first indication information sent by the terminal device is used for notifying the network device that the terminal device is in an idle state. When the terminal device does not perform 504, the first indication information is used to notify the network device to transition the terminal device to an idle state.

The process of the terminal device initiating the registration procedure is slightly different based on whether the terminal device has performed 504, which will be described separately below.

The first situation is as follows: the terminal device executes 504 and the terminal device transitions itself to an idle state and initiates a registration process.

And the terminal equipment performs inter-RAT cell reselection in an inactive state, if the terminal equipment only selects the second cell, but does not move and reside to the second cell. At this time, the terminal device is changed into an idle state in the first cell, a registration process is initiated in the first cell, and the first indication information is sent to the network device through the registration request message in the registration process, where the terminal device is in the idle state.

The terminal device in the inactive state may also select and move to the second cell and change itself to the idle state. Then, the terminal device may initiate a registration procedure in the second cell, and send the first indication information to notify the network device through the registration request message in the registration procedure, where the terminal device is in an idle state.

Illustratively, the NAS layer of the terminal device initiates a registration procedure to send first indication information to the AMF to notify the AMF that the terminal device is in an idle state at this time. The AMF may keep the network state and the terminal device consistent by initiating AN release, and both the network state and the terminal device transition to AN idle state. The process of performing state synchronization by the AMF according to the first indication information may be:

and the AMF deletes the terminal context information locally stored by itself.

The AMF informs the S-RAN to release signaling plane connection and/or user plane resources. And the AMF indicates that the S-RAN terminal equipment of the access network equipment to which the first cell belongs enters an idle state.

And the S-RAN deletes the context information of the terminal equipment according to the indication.

The S-RAN initiates RRC connection release with the terminal device.

And the AMF indicates that the access network equipment T-RAN terminal equipment to which the second cell belongs enters an idle state.

And the T-RAN deletes the context information of the terminal equipment according to the indication.

The T-RAN initiates RRC connection release with the terminal device. The AMF notifies the UPF to release the resources of the N3 interface through a Session Management Function (SMF). N3 is the interface between the access network device and the core network device.

It should be noted that the process of state synchronization is not limited to the above steps, and the AMF may also perform other actions to synchronize the network device and the terminal device in the idle state. The above steps are also exemplary only and are not required to perform every one of the recited steps.

Case two: the terminal device does not perform 504. The terminal equipment is still in an inactive state after finishing cell reselection, and then initiates a registration process.

In case two, the terminal device performs inter-RAT cell reselection in the inactive state. Similarly to the case, the terminal device may select only the second cell, but does not move to and camp on the second cell. At this time, the terminal device is still in the inactive state, and initiates a registration process in the first cell, and in the registration process, the first indication information is sent through the registration request message to notify the network device to convert the terminal device into the idle state.

The terminal device may also be selected and moved to the second cell. At this time, the terminal device is still in the inactive state, and initiates a registration process in the second cell, and in the registration process, the first indication information is sent through the registration request message to notify the network device to convert the terminal device into the idle state.

Alternatively, the terminal device moves and camps on the second cell. At this time, the terminal device is in a connected state, and initiates a registration procedure in the connected state. And in the registration process, first indication information is sent through a registration request message to inform network equipment to convert the terminal equipment into an idle state.

Illustratively, the NAS layer of the terminal device initiates a registration procedure to send first indication information to the AMF for notifying the AMF to transition the terminal device into an idle state. The network device may convert the terminal device into the idle state by: the AMF makes the terminal device transit to the idle state by initiating AN release, and the network device also transits to the idle state, so that the network state and the terminal device are kept consistent. The process of performing state synchronization by the AMF according to the first indication information may be:

the AMF deletes the locally stored terminal context information;

the AMF informs the S-RAN to release signaling plane connection and/or user plane resources;

the AMF instructs the terminal equipment to release the NAS connection;

the AMF indicates that the access network equipment S-RAN terminal equipment to which the first cell belongs enters an idle state;

the S-RAN deletes the context information of the terminal equipment according to the indication;

S-RAN initiates RRC connection release with terminal equipment;

the AMF indicates that the access network equipment T-RAN terminal equipment to which the second cell belongs enters an idle state;

the T-RAN deletes the context information of the terminal equipment according to the indication;

the T-RAN initiates RRC connection release with the terminal equipment;

the T-RAN releases signaling plane connection and/or user plane resources;

the AMF notifies the UPF to release the resources of the interface of N3 through a Session Management Function (SMF). N3 is the interface between the access network device and the core network device.

It should be noted that the process of state synchronization is not limited to the above steps, and the AMF may also perform other actions to synchronize the network device and the terminal device in the idle state. The above steps are also exemplary only and do not require the performance of every listed step.

In 505, the terminal device initiates a registration procedure for NAS signaling connection recovery, where the NAS signaling is signaling transmitted between the terminal device and the core network. The terminal equipment sends first indication information to a core network in a registration process. And the core network performs state synchronization according to the first indication information.

The AMF may also perform other actions to synchronize the network device and the terminal device in an idle state, which is not limited in this embodiment of the present application.

In the first embodiment of the application, the terminal device performs inter-RAT cell (re-) selection in the inactive state, and the AS layer obtains RAT change through system information of the second cell and reports the RAT change to the NAS layer. The NAS layer initiates a registration process to inform the network equipment that the terminal equipment is in an idle state, or informs the network equipment that the terminal equipment is converted into the idle state. In the second embodiment, the NAS layer senses RAT change through information of the second cell, and notifies the network device by initiating a registration procedure, so as to implement state synchronization between the network device and the terminal device, avoid wasting air interface resources when the network device sends data/signaling to the terminal device, reduce downlink data/signaling transmission delay, and avoid data loss or call failure and other problems caused by too long transmission delay.

Example two

In the second embodiment of the present application, the terminal device is in an inactive state in the first cell, and is configured to select or reselect from the first cell to the second cell through the cell. The difference from the first embodiment is that: in the second embodiment, the terminal device may transition itself to the idle state when completing the cell selection or reselection process. The AS layer of the terminal equipment informs the NAS layer of sending first indication information, wherein the first information carries a reason value, and the reason value is different about the wireless access technologies of the first cell and the second cell. The NAS layer initiates a registration procedure in response to the cause value.

Fig. 6 is a flowchart of a communication method according to a second embodiment of the present application, where fig. 6 shows that a terminal device includes an AS layer and an NAS layer, and a network device takes a core network AMF AS an example. The method comprises the following steps:

601: the terminal equipment reselects from a first cell to a second cell through the cell, the RAT of the first cell is different from that of the second cell, and the terminal equipment is in an inactive state in the first cell.

601 is the same as 201 or 401 and will not be described further herein.

602: the terminal equipment changes itself from an inactive state to an Idle state (RRC-Idle).

The terminal equipment is in an inactive state in the first cell, and performs inter-RAT cell (re-) selection, and the terminal equipment is from the first cell to the second cell. The terminal equipment can delete the context information in the terminal equipment, so that the connection state is converted into an idle state. In the second embodiment, the terminal device may transition itself to the idle state when completing the cell reselection.

In the second embodiment of the present application, before 602, the method may also include: and the AS layer of the terminal equipment receives the system information of the second cell, wherein the system information of the second cell comprises the information of the second cell. Wherein the information of the second cell comprises at least one of: identification information of the second cell, identification information of a public land mobile network supported by the second cell, or radio access technology information of the second cell. Unlike the first embodiment, the AS layer of the terminal device will sense that the RAT is changed according to the information of the second cell. So that the terminal device changes itself from the inactive state to the idle state.

603: optionally, the AS layer of the terminal device notifies the NAS layer of a cause value to send the first indication information, where the cause value is different between the radio access technologies of the first cell and the second cell.

In step 603, when the terminal device transitions to the idle state, the AS layer of the terminal device notifies the NAS layer to send the first indication information. The terminal device may notify the NAS layer of sending the first indication information through the cause value. The cause value is different for RATs of the first cell and the second cell, or the cause value may also be expressed as: the terminal device performs inter-RAT cell (re-) selection. The meaning of the terminal device performing inter-RAT cell (re-) selection is the same as the meaning of the first cell and the second cell different from the RAT, and the meaning is used for indicating the terminal device to reselect to the cell with the different RAT.

The AS layer of the terminal device informs the NAS of the change of the current connection state through the reason value that the RAT is changed. The NAS of the terminal device transmits the first indication information in response to the cause value.

604: the terminal equipment initiates a registration process or a service request process.

The NAS layer of the terminal device can know that the terminal device is already in an idle state at this time according to the notification of the AS layer, and the reason why the terminal device is changed into the idle state is that the terminal device performs inter-RAT cell (re-) selection. The terminal equipment responds to the reason value to initiate a registration process. The terminal equipment registers the request message in the registration process, and the registration request message comprises first indication information. The first indication information is used for informing the network equipment that the terminal equipment is in an idle state. Or the terminal device initiates a service request process, and sends a service request message in the service request process, wherein the service request message comprises the first indication information.

Similar to the embodiment, the terminal device may initiate the registration procedure in the first cell, or may initiate the registration procedure after moving to the second cell.

The network device in step 604 may be an AMF, and the AMF performs state synchronization according to the first indication information. The AMF can keep the network state and the terminal device consistent by initiating AN release, and both the network state and the terminal device are transitioned to AN idle state.

The process of performing state synchronization by the AMF according to the first indication information may be:

the AMF deletes the locally stored terminal context information;

the AMF informs the S-RAN to release the signaling plane connection and/or the user plane resource between the S-RAN and the terminal equipment;

the AMF indicates that S-RAN terminal equipment to which the first cell belongs enters an idle state, and the S-RAN deletes context information of the terminal equipment according to the indication;

the AMF notifies the UPF to release the interface resource of N3 through a Session Management Function (SMF). N3 is the interface between the access network device and the core network device.

In the second embodiment of the application, the terminal device reselects the second cell through the cell to convert the terminal device into an idle state. The AS layer sends a reason value to the NAS layer to indicate the reason for changing the NAS layer into the idle state, the NAS layer responds to the reason value to send first indication information, and the first indication information is used for informing the network equipment that the terminal equipment is in the idle state. In the second embodiment, the NAS layer initiates a registration procedure according to the cause value of the AS layer, and notifies the network device that the current state of the terminal device has changed, so AS to implement state synchronization between the network device and the terminal device, avoid wasting air interface resources when the network device sends data/signaling to the terminal device, reduce downlink data/signaling transmission delay, and avoid problems such AS data loss or call failure caused by too long transmission delay.

EXAMPLE III

The third embodiment of the present application is also applicable to the application scenario in fig. 3. The third embodiment is different from the first and second embodiments in that: the terminal device in the inactive state of the first cell requests RRC connection release (e.g., RRC connection release or RRC release) from the first cell to the second cell through cell selection or reselection by the terminal device through an AS layer message.

For the implementation that the terminal device requests RRC (connection) release through an AS layer message, two modes are provided in the third embodiment of the present application.

The first method is as follows: the terminal device reselects to the second cell but has not camped on the second cell. The terminal device remains connected to the first cell at this time. The terminal device sends an AS message to an S-RAN to which the first cell belongs through an AS layer, wherein the AS message is used for requesting radio resource connection release (RRC connection release or RRC release) from the S-RAN.

The second method comprises the following steps: and the terminal equipment reselects to the second cell and resides in the second cell. The terminal device remains connected to the second cell at this time. And the terminal equipment sends an AS message to the T-RAN to which the second cell belongs through the AS layer, and the T-RAN informs the S-RAN of the first cell to carry out radio resource connection release through the AMF.

The two modes will be separately explained below.

The first method is as follows:

fig. 7 is a flowchart of a communication method provided in a third embodiment of the present application, and as shown in fig. 7, the method includes:

701: the terminal equipment reselects from a first cell to a second cell through the cell, the RAT of the first cell is different from that of the second cell, and the terminal equipment is in an inactive state in the first cell.

The terminal device is in an inactive state in the first cell, where the inactive state may refer to a radio resource control inactive state. The inactive state is a state in which: the terminal device remains in the CM-CONNECTED state and the terminal device can move within the RNA region without notifying the NG-RAN. When the terminal device is in the inactive state, the last serving access network maintains the context of the terminal device and the connection associated with the terminal device with the serving AMF and the User Plane Function (UPF). When the terminal equipment is seen from the core network, the terminal equipment is in a connected state. When the terminal equipment is in RRC _ INACTIVE, if the last service access network receives the downlink data from UPF or the downlink signaling from AMF, the access network pages the terminal equipment in all cells of RNA, if the cells of RNA belong to adjacent access networks, the access network sends paging information to the corresponding adjacent access nodes through an Xn port.

In the third embodiment of the present application, RATs of the first cell and the second cell may be different. Illustratively, the RAT of the first cell may be NR and the RAT of the second cell may be E-UTRA. Or the RAT of the first cell may be E-UTRA and the RAT of the second cell may be NR. Or the RAT of the first cell may be E-UTRA and the RAT of the second cell may be LTE. Or the RAT of the first cell may be NR and the RAT of the second cell may be UTRA. Or the RAT of the first cell may be UTRA and the RAT of the second cell may be NR. . It should be noted that this is merely exemplary.

In the third embodiment of the present application, the terminal device reselecting from the first cell to the second cell through the cell may refer to: the terminal equipment performs cell measurement on the first cell, and selects the second cell as a new cell. Or, after selecting the second cell as the new cell, the terminal device receives the system information of the second cell, and determines that the second cell can normally camp. Or the terminal equipment determines that the second cell can normally reside and then resides in the second cell. One of the three cases described above may be understood as the terminal device reselecting from a first cell to a second cell through a cell.

702: the terminal equipment sends an access layer message, and the access layer message is used for requesting the release of the wireless resource connection. And carrying out inter-RAT cell (re-) selection on the terminal equipment in the non-activated state of the first cell, and reselecting to the second cell to be converted into an idle state. In the third embodiment of the present application, when the terminal device reselects the second cell, the AS message is sent to the S-RAN to which the first cell belongs through the AS layer, and the AS message is used to request radio resource connection release (RRC connection release or RRC release) from the S-RAN. At this time, the terminal device reselecting to the second cell means that the terminal device has selected the second cell but has not camped on the second cell. The terminal device is still camped on the first cell. Thus, the terminal device may send an access stratum message to the first cell for requesting a radio resource connection release.

The AS message may include a cause value, which is related to the terminal device requesting the radio resource connection release.

Although not shown in fig. 7, in the third embodiment of the present application, the S-RAN of the first cell and the T-RAN of the second cell access the same 5G core network device, which is the same as the first embodiment and the second embodiment. The 5G core network device may be an AMF.

And the S-RAN performs state transition on synchronization according to the received AS message. The S-RAN can keep the network state and the terminal equipment consistent by initiating AN release, and the network state and the terminal equipment are both converted into AN idle state. The process of the S-RAN making the state transition according to the AS message may include, but is not limited to, the following steps:

the S-RAN sends a Context Release Request message (N2 UE Context Release Request) to the AMF;

AMF sends Context Release instruction information (N2 UE Context Release Command) to instruct RAN to Release the Context of the terminal equipment; the AMF informs the S-RAN to release the signaling plane connection and/or user plane resources between the S-RAN and the terminal equipment; the S-RAN deletes the context of the terminal equipment; the AMF instructs the SMF to notify the UPF to release the interface resources of N3. N3 is the interface between the access network device and the core network device.

In the first mode of the third embodiment of the present application, a terminal device in AN inactive state performs inter-RAT cell (re-) selection, the terminal device sends AN RRC connection release request message, and AN S-RAN may execute AN release or other procedures according to the received RRC connection release request message, so that the network device and the terminal device are both in AN idle state. Therefore, the state synchronization of the network equipment and the terminal equipment is realized, the waste of air interface resources when the network equipment sends data/signaling to the terminal equipment is avoided, the transmission delay of downlink data/signaling is reduced, and the problems of data loss or call failure and the like caused by overlong transmission delay are avoided.

The second method comprises the following steps:

fig. 8 is a flowchart of another communication method provided in the third embodiment of the present application, and as shown in fig. 8, the method includes:

801: the terminal equipment reselects from a first cell to a second cell through the cell, the RAT of the first cell is different from that of the second cell, and the terminal equipment is in an inactive state in the first cell.

801 are the same as 701 and will not be described in detail here.

802: and the terminal equipment sends an access layer message to the second cell, wherein the access layer message is used for requesting the release of the wireless resource connection.

In 802, unlike 702, the terminal device reselecting to the second cell means that the terminal device has camped on the second cell. The terminal device is in a connected state in the second cell. At this time, the terminal device sends an access stratum message to the T-RAN to which the second cell belongs, and the access stratum message is used for requesting release of radio resource connection with the first cell.

803: and the second cell sends a first message to the AMF, wherein the first message is used for requesting the AMF to indicate the first cell to carry out radio resource connection release.

And the T-RAN to which the second cell belongs sends a first message to the AMF according to the received AS message, and requests the AMF to indicate the first cell to carry out radio resource connection release.

804: the AMF transmits RRC connection release indication information.

The AMF sends indication information to the S-RAN according to the first message, and the indication information is used for indicating the S-RAN to carry out radio resource connection release.

And the S-RAN synchronously performs state transition according to the received RRC connection release indication information. The S-RAN can keep the network state and the terminal equipment consistent by initiating AN release, and the network state and the terminal equipment are both converted into AN idle state. The process of the S-RAN making the state transition according to the AS message may include, but is not limited to, the following steps:

the S-RAN sends a Context Release Request message (N2 UE Context Release Request) to the AMF; AMF sends Context Release instruction information (N2 UE Context Release Command) to instruct RAN to Release the terminal device Context; the AMF informs the S-RAN to release the signaling plane connection and/or user plane resources between the S-RAN and the terminal equipment; the S-RAN deletes the context of the terminal equipment; the AMF instructs the SMF to notify the UPF to release the interface resource of N3. N3 is an interface between an access network device and a core network device.

It should be noted that the process of state synchronization is not limited to the above steps, and other actions may be performed to synchronize the network device and the terminal device in the idle state. The above steps are also exemplary only and do not require the performance of every listed step.

The foregoing describes a method for communication in an embodiment of the present application, and hereinafter, a device for communication in various embodiments of the present application will be described. For example, the apparatus may employ the method shown in embodiment one to embodiment three. The device is based on the same technical conception, and because the principles of solving the problems of the method and the device are similar, the implementation of the device and the method can be mutually referred, and repeated parts are not described again.

The embodiment of the present application provides a communication apparatus for performing the actions performed by the terminal device in the first embodiment and the second embodiment. The communication device includes: a processing module, configured to reselect the communication device from a first cell to a second cell through a cell, where radio access technologies of the first cell and the second cell are different, and the communication device is in a radio resource control inactive state in the first cell;

and the transceiver module is used for sending a registration request message to initiate a registration process.

The communication device provided by the embodiment of the application performs inter-RAT cell (re-) selection in an inactive state to initiate a registration process for NAS signaling connection recovery. The communication device in the embodiment of the application can enable the network equipment to update the information under the condition that the RATs are different.

The communication apparatus provided in this embodiment may also be configured to execute the method in any possible implementation manner of the first embodiment and the second embodiment, and specific content may be partial content of the action executed by the terminal device in the first embodiment and the second embodiment, which is not described herein again.

The embodiment of the present application provides a communication apparatus, which is configured to perform the actions performed by the terminal device in the third embodiment. The communication device includes: a processing module, configured to reselect the communication device from a first cell to a second cell through a cell, where radio access technologies of the first cell and the second cell are different, and the communication device is in a radio resource control inactive state in the first cell.

A receiving and sending module, configured to send an access stratum message, where the access stratum message is used to request radio resource connection release.

The terminal device provided in the embodiment of the present application sends AN RRC connection release request message to the network device when the terminal device is in AN inactive state inter-RAT cell (re-) selection, and the network device may execute AN release or other procedures according to the received RRC connection release request message, so that the network device and the terminal device are both in AN idle state. Therefore, the state synchronization of the network equipment and the terminal equipment is realized, the waste of air interface resources when the network equipment sends data/signaling to the terminal equipment is avoided, the transmission delay of downlink data/signaling is reduced, and the problems of data loss or call failure and the like caused by overlong transmission delay are avoided.

The communication apparatus provided in this embodiment may also be configured to execute the method in any one of the three possible implementation manners of the embodiment, and specific contents may be contents of a part of the action executed by the terminal device in the method in the third embodiment, which are not described herein again.

Fig. 9 is a schematic diagram of a simplified communication apparatus for easy understanding and illustration, and in fig. 9, the communication apparatus is exemplified by a terminal device. As shown in fig. 9, the communication device includes a processor, a memory, a radio frequency circuit, an antenna, and an input-output device. The processor is mainly used for processing communication protocols and communication data, controlling the terminal equipment, executing software programs, processing data of the software programs and the like. The memory is used primarily for storing software programs and data. The radio frequency circuit is mainly used for converting baseband signals and radio frequency signals and processing the radio frequency signals. The antenna is mainly used for receiving and transmitting radio frequency signals in the form of electromagnetic waves. Input and output devices, such as touch screens, display screens, keyboards, etc., are used primarily for receiving data input by a user and for outputting data to the user. It should be noted that some kinds of terminal devices may not have input/output devices.

When data needs to be sent, the processor performs baseband processing on the data to be sent and outputs baseband signals to the radio frequency circuit, and the radio frequency circuit performs radio frequency processing on the baseband signals and sends the radio frequency signals to the outside in the form of electromagnetic waves through the antenna. When data is transmitted to the terminal equipment, the radio frequency circuit receives radio frequency signals through the antenna, converts the radio frequency signals into baseband signals and outputs the baseband signals to the processor, and the processor converts the baseband signals into the data and processes the data. For ease of illustration, only one memory and processor are shown in FIG. 9. In an actual end device product, there may be one or more processors and one or more memories. The memory may also be referred to as a storage medium or a storage device, etc. The memory may be provided independently of the processor, or may be integrated with the processor, which is not limited in this embodiment.

In the embodiment of the present application, the antenna and the rf circuit having the transceiving function may be regarded as a transceiving module of the communication device, and the processor having the processing function may be regarded as a processing module of the communication device. As shown in fig. 9, the communication apparatus includes a transceiver module 901 and a processing module 902. A transceiver module may also be referred to as a transceiver, a transceiving device, etc. A processing module may also be referred to as a processor, a processing board, a processing device, etc. Optionally, a device in the transceiver module 901 for implementing a receiving function may be regarded as a receiving module, and a device in the transceiver module 901 for implementing a sending function may be regarded as a sending module, that is, the transceiver module 901 includes a receiving module and a sending module. A transceiver module may also sometimes be referred to as a transceiver, transceiving circuitry, or the like. A receiving module may also sometimes be referred to as a receiver, or receiving circuitry, etc. The transmitting module may also sometimes be referred to as a transmitter, or a transmitting circuit, etc.

It should be understood that the transceiver module 901 is configured to perform the transmitting operation and the receiving operation on the terminal device side in the above method embodiment, and the processing module 902 is configured to perform other operations besides the transceiving operation on the terminal device in the above method embodiment.

For example, in one implementation, the transceiver module 901 is configured to perform a receiving operation at the terminal device side in 202 in fig. 2, and/or the transceiver module 901 is further configured to perform other transceiving steps at the terminal device side in this embodiment of the present application. The processing module 902 is configured to execute 201 in fig. 2, and/or the processing module 902 is further configured to execute other processing steps on the terminal device side in this embodiment of the present application.

For another example, in another implementation manner, the transceiver module 901 is configured to perform a receiving operation at the terminal device side in 402 in fig. 4, and/or the transceiver module 902 is further configured to perform other transceiving steps at the terminal device side in this embodiment of the present application. The processing module 902 is configured to execute 401 in fig. 4, and/or the processing module 902 is further configured to execute other processing steps on the terminal device side in this embodiment of the present application.

For another example, in another implementation manner, the transceiver module 901 is configured to perform the receiving operation at the terminal device side in 502 and 503 in fig. 5, and/or the transceiver module 902 is further configured to perform other transceiving steps at the terminal device side in this embodiment of the present application. The processing module 902 is configured to execute 501, 504, and 505 in fig. 5, and/or the processing module 902 is further configured to execute other processing steps on the terminal device side in this embodiment of the present application.

For another example, in another implementation manner, the transceiver module 901 is configured to perform a receiving operation at the terminal device side in 603 in fig. 6, and/or the transceiver module 902 is further configured to perform other transceiving steps at the terminal device side in this embodiment of the present application. The processing module 902 is configured to execute 601, 602, and 604 in fig. 6, and/or the processing module 902 is further configured to execute other processing steps on the terminal device side in this embodiment.

For another example, in another implementation manner, the transceiver module 901 is configured to perform a receiving operation at the terminal device side in 702 in fig. 7, and/or the transceiver module 902 is further configured to perform other transceiving steps at the terminal device side in this embodiment of the present application. The processing module 902 is configured to execute 701 in fig. 7, and/or the processing module 902 is further configured to execute other processing steps on the terminal device side in this embodiment of the present application.

For another example, in another implementation manner, the transceiver module 901 is configured to perform receiving operations on the terminal device side in 802, 803, and 804 in fig. 8, and/or the transceiver module 902 is further configured to perform other transceiving steps on the terminal device side in this embodiment of the present application. The processing module 902 is configured to execute 801 in fig. 8, and/or the processing module 902 is further configured to execute other processing steps on the terminal device side in the embodiment of the present application.

When the communication device is a chip-like device or circuit, the chip device may include a transceiver module and a processing module. The transceiver module can be an input-output circuit and/or a communication interface; the processing module is a processor or a microprocessor or an integrated circuit integrated on the chip.

When the communication device in this embodiment is a terminal device, reference may be made to the device shown in fig. 10. In fig. 10, the apparatus includes a processor 1010, a transmit data processor 1020, and a receive data processor 1030. The processing module in the above embodiment may be the processor 1010 in fig. 10, and performs the corresponding functions. The transceiver module in the above embodiments may be the transmit data processor 1020 and/or the receive data processor 1030 of fig. 10. Although fig. 10 shows a channel encoder and a channel decoder, it is understood that these blocks are not limitative and only illustrative to the present embodiment.

Fig. 11 shows another form of the present embodiment. The processing device 1110 includes modules such as a modulation subsystem, a central processing subsystem, and peripheral subsystems. The communication device in this embodiment may serve as a modulation subsystem therein. In particular, the modulation subsystem may include a processor 1130, an interface 1140. The processor 1130 performs the functions of the processing module, and the interface 1140 performs the functions of the transceiver module. As another variation, the modulation subsystem includes a memory 1160, a processor 1130, and a program stored on the memory 1160 and executable on the processor, and the processor 1130 executes the program to implement the method of the terminal device side in the above method embodiments. It should be noted that the memory 1160 may be non-volatile or volatile, and may be located within the modulation subsystem or within the processing device 1110, as long as the memory 1160 may be coupled to the processor 1130.

Claims

1. A method of communication, comprising:

a terminal device moves from a first cell to a second cell, wherein the terminal device is allocated with a registration area, and the registration area comprises the first cell and the second cell;

and when the terminal equipment moves from the first cell to the second cell through cell selection or reselection, the wireless access technologies of the first cell and the second cell are different, and the terminal equipment is in an inactive state in the first cell, the terminal equipment initiates a registration process.

2. The method of claim 1,

the terminal equipment initiates a registration process, which comprises the following steps: the non-access stratum of the terminal equipment receives indication information from the access stratum of the terminal equipment, the indication information is used for indicating the terminal equipment to carry out cell selection or reselection across wireless access technologies, and the terminal equipment responds to the indication information to initiate a registration process.

3. The method of claim 1 or 2,

the registration process comprises the following steps: an initial registration flow, or, a mobile and periodic registration update flow.

4. The method of claim 1 or 2,

the terminal equipment initiates a registration process, which comprises the following steps: the terminal equipment sends first indication information, wherein the first indication information is used for informing network equipment to convert the terminal equipment into an idle state; or

The method further comprises the following steps: the terminal equipment is converted into an idle state;

the process of initiating the registration by the terminal equipment comprises the following steps: the terminal equipment sends first indication information, and the first indication information is used for informing network equipment that the terminal equipment is in an idle state.

5. The method of claim 4,

the terminal equipment initiates a registration process, which comprises the following steps: the terminal device sends a registration request message, where the registration request message is used to initiate the registration process, and the registration request message includes the first indication information.

6. The method of claim 4, further comprising:

and the access layer of the terminal equipment informs the non-access layer of the terminal equipment of sending the first indication information.

7. The method of claim 6,

the informing, by the access layer of the terminal device, that the non-access layer of the terminal device sends the first indication information includes: and the access layer of the terminal equipment informs a non-access layer of the terminal equipment of sending the first indication information through a reason value, wherein the reason value is different about the wireless access technologies of the first cell and the second cell.

8. The method of claim 4,

the non-access stratum of the terminal equipment sends first indication information according to the information of the second cell received by the access stratum of the terminal equipment, wherein the information of the second cell comprises at least one of the following items:

identification information of the second cell, identification information of a public land mobile network supported by the second cell, or radio access technology information of the second cell.

9. The method of claim 8, further comprising:

the access layer receives system information of the second cell, wherein the system information comprises information of the second cell;

the access layer informs the non-access layer of the received information of the second cell.

10. The method of claim 4, wherein:

the network equipment comprises access network equipment or core network equipment, and the core network equipment comprises an access and mobility management functional entity.

11. The method of claim 10,

the sending the first indication information comprises: and sending the first indication information to the access and mobility management functional entity.

12. The method of claim 1 or 2,

the radio access technology of the first cell comprises a new air interface or evolved universal land-based radio access.

13. The method of claim 1 or 2,

and the first cell and the second cell access 5G core network equipment.

14. A communications apparatus, comprising:

a processing module to move the communication device from a first cell to a second cell, the communication device being assigned a registration area comprising the first cell and the second cell;

the processing module is configured to initiate a registration procedure if the communication device moves from the first cell to the second cell through cell selection or reselection, the first cell and the second cell have different radio access technologies, and the communication device is in an inactive state in the first cell.

15. The communications apparatus of claim 14,

the processing module is configured to initiate a registration procedure and includes: a non-access stratum of the communication device receives indication information from an access stratum of the communication device, the indication information indicating that the communication device has performed cell selection or reselection across radio access technologies, the non-access stratum of the communication device initiating the registration procedure in response to the indication information.

16. The apparatus of claim 14 or 15,

17. The apparatus of claim 14 or 15,

the communication apparatus further includes: a transceiver module, configured to send first indication information in the registration procedure, where the first indication information is used to notify a network device that the communication apparatus is in an idle state; or

The processing module is configured to transition the communication apparatus to an idle state, and the first indication information is used to notify the network device to transition the communication apparatus to the idle state.

18. The apparatus of claim 17,

the processing module, configured to initiate a registration procedure, includes: the processing module is configured to enable the transceiver module to send a registration request message, where the registration request message is used to initiate the registration process, and the registration request message includes the first indication information.

19. The apparatus of claim 17,

the access stratum of the communication device is used for informing the non-access stratum of the communication device to send the first indication information.

20. The apparatus of claim 19,

the access stratum of the communication device being configured to notify a non-access stratum of the communication device to send the first indication information includes: the access stratum of the communication device is used for informing a non-access stratum of the communication device of sending the first indication information through a reason value, wherein the reason value is different about the radio access technologies of the first cell and the second cell.

21. The apparatus of claim 17,

the access stratum of the communication device being configured to notify a non-access stratum of the communication device to send the first indication information includes: the non-access stratum layer is used for sending first indication information according to the information of the second cell received by the access stratum layer, and the information of the second cell comprises at least one of the following items:

22. The apparatus of claim 21,

the access stratum of the communication device is used for receiving system information of the second cell, wherein the system information comprises information of the second cell;

the access stratum is used for informing the non-access stratum of the received information of the second cell.

23. The apparatus of claim 17, wherein:

24. The apparatus of claim 23,

the transceiver module is configured to send first indication information in the registration procedure, where the sending includes: the transceiver module is configured to send the first indication information to the access and mobility management functional entity.

25. The apparatus of claim 14 or 15,

the radio access technology of the first cell comprises a new air interface or evolved universal terrestrial radio access.

26. The apparatus of claim 14 or 15,

and the first cell and the second cell access 5G core network equipment.

27. A communications apparatus, comprising:

a transceiver for executing instructions for receiving and transmitting information, and a processor, which when executed by the processor, causes the communication device to perform the method of any of claims 1-13.

28. A computer-readable storage medium, characterized in that,

the computer-readable storage medium has stored thereon a computer program, characterized in that the program is executed by a processor for performing the method according to any of claims 1-13.

29. A communications apparatus comprising a memory to store instructions and a processor to execute the memory-stored instructions and perform the method of any of claims 1-13 on the instructions stored in the memory.

30. A communication system, characterized in that it comprises a communication device according to any one of claims 14-26.