CN108616950B

CN108616950B - Mobility management method between wireless access networks, core network equipment and base station

Info

Publication number: CN108616950B
Application number: CN201611235422.2A
Authority: CN
Inventors: 梁靖
Original assignee: China Academy of Telecommunications Technology CATT
Current assignee: China Academy of Telecommunications Technology CATT; Datang Mobile Communications Equipment Co Ltd
Priority date: 2016-12-28
Filing date: 2016-12-28
Publication date: 2019-12-20
Anticipated expiration: 2036-12-28
Also published as: WO2018121644A1; CN108616950A

Abstract

The invention provides a mobility management method among wireless access networks, core network equipment and a base station. When the terminal in the non-activated state moves among different systems, the invention still keeps the user context information when the terminal is in the non-activated state in the NR system, and the user context information is not deleted until certain conditions are met. The invention can realize the inter-RAT mobility management of the terminal in the non-activated state, solve the mobility problem among different systems and ensure that the terminal can work normally.

Description

Mobility management method between wireless access networks, core network equipment and base station

Technical Field

The invention relates to the technical field of mobile communication, in particular to a mobility management method among wireless access networks, core network equipment and a base station.

Background

With the development of wireless communication systems, terminal types and service types are diversified, and the terminal saves power, saves network resources, and meets the requirements of various service types. In order to guarantee both power saving and fast data transmission of the terminal, a New mobility state is introduced in a New radio access technology (New RAT) of a New air interface (NR) system of 5G: RRC _ INACTIVE (also referred to herein as INACTIVE or INACTIVE state).

The terminal keeps the core network connection in the inactive state, but does not perform the conventional operation (such as switching, uplink timing update, radio link monitoring, and the like) in the air interface connection state, and does not allocate the terminal identifier (such as C-RNTI) directly used for air interface transmission, so that the air interface scheduling transmission cannot be directly performed. In the inactive state, the terminal needs to monitor the paging message to ensure that the call from the network side can be received.

Fig. 1 is an interface in a network architecture of a next generation (NextGen) network, where the gNB is a base station in a New RAT (NR) system. NG2 denotes a Radio Access Network (RAN) and a control plane interface of a core Network, and NG3 denotes a user plane interface of the RAN and the core Network. The NR base station gNB is connected to a user plane functions (UP functions) unit of the 5G Core network (NGC, NextGen Core) through a user plane interface NG3, and is connected to a control plane functions (CP functions) unit of the NGC through a control plane interface NG 2. In the inactive state of a terminal (UE), the RAN node releases the Radio Resource Control (RRC) connection of the UE, but still retains the connection of the NG2 and NG3 interfaces of the UE. The UE is transparent to the core network in this state, i.e. the core network still considers that the UE is always in a connected state, so downlink signaling or data will reach the RAN node, and the RAN needs to page the UE at this time.

The concept of location areas at the core network level (CN level) and the radio access network level (RAN level) is described below.

The CN level location Area, i.e. the UE location Area controlled by the core network, is generally called Tracking Area (TA). In the prior art, a core network always configures a TA list (TAI list) for a UE through a Non Access Stratum (NAS) message. The UE stores a TAI List configured by a core network, when a cell is resided (a terminal is in an idle state) or accessed (the terminal is in a connected state), a system message broadcasted by a cell idle port is read, information is obtained from the system message, if the TAI is not stored in the TAI List, the UE initiates a Tracking Area Update (TAU) process, and a new TAI List is obtained through interaction with NAS signaling of the core network.

Before the inactive state is not introduced, the UE only has an idle state and a connected state, the position area of the UE in the idle state is TA, and the position area in the connected state is a cell. After the inactive state is introduced, a RAN level location Area, namely a RAN Notification Area (RNA) is introduced for the UE. The RNA may comprise a plurality of cells. A RAN network side node NR base station (gNB) may send notification messages to find UEs in multiple cells within an RNA region. When the UE moves out of an RNA, RNA update is needed so that the RAN network side node can find the UE.

The TA and RNA are UE location areas maintained by the core network node and the RAN node, respectively, and function to enable the core network node and the RAN node to perform location area tracking on the UE, respectively. When the UE is in an idle state, the core network searches the UE by sending paging (paging) messages in all cells under a TAIlist area of the UE; when the UE is in inactive state, the RAN node gNB searches for the UE by sending notification messages (notification) in all cells in the RNA region.

The cross-radio access technology (inter-RAT) network architecture of NR and eLTE/LTE is described below.

Referring to the inter-RAT network architecture of lte and NR shown in fig. 2, NR base stations gNB and lte base stations lte eNB are both connected to a 5G Core network (NGC, NextGen Core). As can be seen, both the gNB and eNB are connected to the NGC through a User Plane (UP) interface and a Control Plane (CP) interface.

Please refer to the inter-RAT network architecture of LTE and NR shown in fig. 3. Where the NR base station gNB is connected to the 5G Core network NGC and the LTE base station LTE eNB is connected to the 4G Core network Evolved Packet Core (EPC).

Both of the above architectures provided in fig. 2 and 3 are inter-RAT architectures. When an inactive state terminal moves from NR to LTE/LTE network, it is the mobility performed under the above two network architectures. Since there is currently no relevant standardized content for this, the behavior of the UE is uncertain.

From the above analysis, it can be seen that, in the prior art, only the inactive state of the NR system is defined, and when the UE in the inactive state moves from the NR system to another communication system (e.g. LTE/LTE system), since the other communication system does not have the inactive state, the terminal cannot keep the inactive state, and at this time, the behavior of the terminal is uncertain, and the terminal cannot operate normally.

Disclosure of Invention

The technical problem to be solved in the embodiments of the present invention is to provide a mobility management method between wireless access networks, core network equipment, and a base station, so as to implement mobility management after inactive UE enters an eLTE/LTE network from an NR network.

In order to solve the foregoing technical problem, an embodiment of the present invention provides a method for mobility management between radio access networks, where a radio access network includes a first radio access network RAN and a second RAN, where the first RAN is a RAN of a new air interface NR system, and the method includes:

the terminal in the non-activated state detects that the terminal is accessed from a first RAN to a second RAN;

and the terminal switches the self state from the inactive state to an idle state and continuously retains the user context information of the terminal in the inactive state in the NR system.

In the above method, after the step of switching the self state from the inactive state to the idle state by the terminal, the method further includes:

and if the terminal detects that the terminal is accessed back to the first RAN again, switching the state of the terminal back to the inactive state, and recovering the user context information of the terminal in the inactive state in the NR system.

In the above method, the second RAN is a RAN of an lte system, and after the step of switching the self state of the terminal from the inactive state to the idle state, if the terminal initiates an uplink signaling process in the second RAN, the method further includes:

in the process of triggering establishment of RRC connection in the uplink signaling process, the terminal sends prompt information of a first base station, which stores user context information when the terminal is in an inactive state in an NR system, to a network side, wherein the prompt information is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station;

and in the process of triggering and establishing RRC connection in the uplink signaling process or after receiving a paging message sent by a network side after the uplink signaling process is finished, the terminal deletes locally-reserved user context information when the terminal is in an inactive state in an NR system.

In the above method, the second RAN is a RAN of an lte system, and after the step of switching the self state of the terminal from the inactive state to the idle state, if the terminal initiates an uplink service process in the second RAN, the method further includes:

in the process of triggering and establishing RRC connection in the uplink service process, the terminal sends prompt information of a first base station, which stores user context information when the terminal is in an inactive state in an NR system, to a network side, wherein the prompt information is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station;

and in the process of triggering and establishing RRC connection in the uplink service process, the terminal deletes the locally-reserved user context information when the terminal is in an inactive state in the NR system.

In the above method, the second RAN is a RAN of an LTE system, and after the step of switching the self state from the inactive state to an idle state by the terminal, the method further includes:

if the terminal initiates an RRC connection establishment process, the terminal deletes locally-reserved user context information when the terminal is in an inactive state in an NR system, and sends prompt information of a first base station, which stores the user context information when the terminal is in the inactive state in the NR system, to a network side, wherein the prompt information is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station.

the terminal starts a timer configured by an NR system in advance;

before the timer is overtime, if the terminal detects that the terminal is accessed back to the first RAN again, the timer is stopped, the state of the terminal is switched back to an inactive state, and user context information of the terminal in the inactive state in an NR system is recovered;

and after the timer is overtime, the terminal deletes the locally-reserved user context information when the terminal is in an inactive state in the NR system.

In the above method, the second RAN is a RAN of an lte system, and after the step of switching the self state of the terminal from the inactive state to the idle state, if the terminal initiates an uplink signaling process in the second RAN before the timer expires, the method further includes:

In the above method, the second RAN is a RAN of an lte system, and after the step of switching the self state of the terminal from the inactive state to the idle state, if the terminal initiates an uplink service process in the second RAN before the timer expires, the method further includes:

if the terminal initiates an RRC connection establishment process before the timer is overtime, the terminal deletes locally-reserved user context information when the terminal is in an inactive state in an NR system, and sends prompt information of a first base station, which stores the user context information when the terminal is in the inactive state in the NR system, to a network side, wherein the prompt information is a current terminal identifier of the terminal, an inactive terminal identifier associated with the user context information, or an identifier of the first base station.

In the above method, after the step of switching back the self state to the inactive state, the method further includes:

and the terminal initiates an RNA updating process of the location area at the RAN level to update RNA.

An embodiment of the present invention further provides a method for mobility management between radio access networks, where a radio access network includes a first radio access network RAN and a second RAN, where the first RAN is a RAN of a new air interface NR system, and the second RAN is a RAN of an lte system, and the method includes:

a first core network of the NR system receives a paging failure message sent when a first base station in a first RAN cannot page a first terminal in an inactive state in a RAN-level location area RNA, where the first base station is a base station that stores user context information of the first terminal in the NR system;

the first core network initiates paging to the first terminal within a core network level location area TA.

In the above method, if a first core network of the NR system receives a notification message sent by a second terminal in a second RAN in an RRC connection setup process triggered in an uplink signaling process, where the notification message is used to notify a second base station in the first RAN, and the second base station is a base station that stores user context information of the second terminal in the NR system; the method further comprises:

and the first core network continuously keeps the connection of the control plane interface NG2 and the connection of the user plane interface GN3 of the second terminal in the NR system according to the prompt message, and sends a notification message for notifying the second base station to continuously keep the connection of the second terminal to the second base station.

In the above method, after the uplink signaling process of the second terminal is finished, the method further includes:

and the first core network releases the connection between the second terminal and the eLTE system.

In the above method, after the step of releasing the connection between the second terminal and the lte system, the method further includes:

the first core network directly pages in a second RAN of an eLTE system when downlink service of the second terminal arrives, and after receiving a paging response message of the second terminal, the first core network transfers NG2 connection and GN3 connection of the second terminal in an NR system from a first base station to a corresponding base station in the second RAN, and sends a notification message used for notifying the second base station to release the connection of the second terminal and delete user context information when the second terminal is in an inactive state in the NR system to the second base station.

In the above method, if the first core network of the NR system receives a prompt message sent by a third terminal in a second RAN in an RRC connection setup process, where the prompt message is used to prompt a third base station in the first RAN, and the third base station is a base station that stores user context information of the third terminal in the NR system, the method further includes:

and the first core network transfers the connection of the control plane interface NG2 and the user plane interface GN3 of the third terminal in the NR system to a corresponding base station in the second RAN according to the prompt message, and sends a notification message for notifying the third base station to release the connection of the third terminal and deleting the user context information of the third terminal when the third terminal is in an inactive state in the NR system to the third base station.

In the above method, the RRC connection establishment procedure is triggered when the third terminal initiates an uplink signaling procedure, or when the third terminal initiates an uplink service procedure.

An embodiment of the present invention further provides another method for managing mobility between radio access networks, where a radio access network includes a first radio access network RAN and a second RAN, where the first RAN is a RAN of a new air interface NR system, and the second RAN is a RAN of an LTE system, and the method includes:

a first core network of the NR system receives a prompt message sent by a terminal in a second RAN in an RRC connection establishment procedure, where the prompt message is used to prompt a first base station in the first RAN, and the first base station is a base station that stores user context information of the terminal in the NR system;

and the first core network sends a notification message for notifying the first base station to release the connection of the terminal and delete the user context information of the terminal in the non-activated state in the NR system to the first base station according to the prompt message.

In the above method, the first core network further receives the hint message forwarded by the EPC through an interface with the EPC of the LTE system.

a first base station in a first RAN initiating paging of a first terminal in an inactive state within a RAN-level location area RNA, the first base station storing user context information of the second terminal in the inactive state in the NR system;

and if the first terminal cannot be paged in the RNA by the first RAN, sending a paging failure message to a first core network of the NR system, wherein the paging failure message is sent when the first terminal cannot be paged in the RNA.

In the above method, if the first base station receives a notification message sent by the first core network to notify the first base station to continue maintaining the connection of the second terminal, the method includes:

and the first base station starts a timer according to the notification message, keeps the connection of the second terminal in the NR system before the timer is overtime, keeps the user context information of the second terminal in the NR system when the second terminal is in the inactive state, releases the connection of the second terminal and deletes the user context information of the second terminal in the inactive state after the timer is overtime.

In the above method, if a first base station receives a notification message sent by a first core network, the notification message being used to notify the first base station to release the connection of the second terminal and to delete the user context information of the second terminal when the second terminal is in an inactive state in an NR system, the method includes:

and the first base station releases the connection of the second terminal and deletes the user context information of the second terminal in the non-activated state in the NR system according to the notification message.

the first base station of the NR system receives a notification message sent by a first core network of the NR system, the notification message being used to notify the first base station to release the connection of the terminal and to delete the user context information when the terminal is in an inactive state in the NR system;

and the first base station releases the connection of the terminal and deletes the user context information of the terminal in the non-activated state in the NR system according to the notification message.

An embodiment of the present invention further provides a terminal, where the terminal includes:

a first detecting unit, configured to detect that the terminal is accessed from a first RAN to a second RAN when the terminal is in an inactive state, where the first RAN is a RAN of a new air interface NR system;

and the first switching unit is used for switching the self state of the terminal from the inactive state to an idle state and continuously and locally retaining the user context information when the terminal is in the inactive state in the NR system.

The above terminal further includes:

a second detecting unit, configured to detect that the terminal is re-accessed to the first RAN;

and the second switching unit is used for switching the self state back to the inactive state when the second detection unit detects that the terminal is accessed back to the first RAN again, and recovering the user context information when the terminal is in the inactive state in the NR system.

In the above terminal, the second RAN is a RAN of an lte system, and the terminal further includes:

a first signaling initiating unit, configured to, after switching a terminal state from the inactive state to an idle state, if an uplink signaling process is initiated in a second RAN and an RRC connection establishment process is triggered in the uplink signaling process, send, by the terminal, to a network side, prompt information of a first base station that stores user context information when the terminal is in an inactive state in an NR system, where the prompt information is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station; and in the process of triggering and establishing RRC connection in the uplink signaling process, or after receiving a paging message sent by a network side after the uplink signaling process is finished, the terminal deletes the locally-reserved user context information when the terminal is in an inactive state in the NR system.

a first service initiating unit, configured to, after switching a terminal state from the inactive state to an idle state, if an uplink service process is initiated in a second RAN and an RRC connection establishment process is triggered in the uplink service process, send, by the terminal, to a network side, prompt information of a first base station that stores user context information when the terminal is in an inactive state in an NR system, where the prompt information is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station; and in the process of triggering and establishing RRC connection in the uplink service process, the terminal deletes the locally-reserved user context information when the terminal is in an inactive state in an NR system.

a first connection establishing unit, configured to delete locally-reserved user context information when the terminal is in an inactive state in an NR system if an RRC connection establishment procedure is initiated after a terminal state is switched from the inactive state to an idle state, and send, to a network side, prompt information of a first base station that stores the user context information when the terminal is in the inactive state in the NR system, where the prompt information is a current terminal identifier of the terminal, an inactive state terminal identifier associated with the user context information, or an identifier of the first base station.

In the above terminal, further comprising:

the timing processing unit is used for starting a timer configured in advance by the NR system after the terminal state is switched from the inactive state to the idle state; before the timer is overtime, if the terminal detects that the terminal is accessed back to the first RAN again, the timer is stopped, the state of the terminal is switched back to the inactive state, and the user context information of the terminal in the inactive state in the NR system is recovered; and after the timer is overtime, deleting the locally-reserved user context information when the terminal is in an inactive state in the NR system.

a second signaling initiating unit, configured to, after the step of switching the terminal state from the inactive state to an idle state, if an uplink signaling process is initiated in a second RAN before the timer expires, send, to a network side, prompt information of a first base station, where user context information when the terminal is in an inactive state in an NR system is stored, in a process of triggering establishment of an RRC connection in the uplink signaling process, where the prompt information is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station; and deleting the locally reserved user context information when the terminal is in an inactive state in the NR system in the process of triggering and establishing RRC connection in the uplink signaling process or after receiving a paging message sent by a network side after the uplink signaling process is finished.

a second service initiating unit, configured to, after switching a terminal state from the inactive state to an idle state, if an uplink service process is initiated in a second RAN before the timer times out, send, to a network side, prompt information of a first base station, where user context information when the terminal is in an inactive state in an NR system is stored, in a process of triggering establishment of an RRC connection in the uplink service process, where the prompt information is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station; and deleting the locally reserved user context information when the terminal is in an inactive state in the NR system in the process of triggering the establishment of the RRC connection in the uplink service process.

a second connection establishing unit, configured to, after switching a terminal state from the inactive state to an idle state, if an RRC connection establishment procedure is initiated before the timer expires, delete locally-reserved user context information when the terminal is in the inactive state in the NR system, and send, to a network side, prompt information of a first base station that stores the user context information when the terminal is in the inactive state in the NR system, where the prompt information is a current terminal identifier of the terminal, an inactive state terminal identifier associated with the user context information, or an identifier of the first base station.

In the above terminal, the terminal further includes:

and the updating unit is used for initiating the RNA updating process of the location area at the RAN level to update RNA after the terminal state is switched back to the inactive state.

An embodiment of the present invention further provides a first core network of a new air interface NR system, including:

a first receiving unit, configured to receive a paging failure message sent when a first base station in a first RAN cannot page a first terminal in an inactive state in a RAN-level location area RNA, where the first base station is a base station that stores user context information of the first terminal in the NR system, and the first RAN is a RAN of a new air interface NR system;

a first paging unit, configured to initiate paging to the first terminal in a location area TA of a core network level.

The above first core network further includes:

a second receiving unit, configured to receive a prompt message sent by a second terminal in a second RAN in an RRC connection setup process triggered in an uplink signaling process, where the prompt message is used to prompt a second base station in the first RAN, the second base station is a base station that stores user context information of the second terminal in the NR system, and the second RAN is a RAN of an lte system;

a first processing unit, configured to continue to maintain the control plane interface NG2 connection and the user plane interface GN3 connection of the second terminal in the NR system according to the hint information, and send a notification message to the second base station for notifying the second base station to continue to maintain the connection of the second terminal.

The above first core network further includes:

and the connection release unit is used for releasing the connection between the second terminal and the eLTE system after the uplink signaling process of the second terminal is finished.

The above first core network further includes:

a first paging unit, configured to, after the connection releasing unit releases the connection between the second terminal and the lte system, directly page in a second RAN of the lte system if a downlink traffic of the second terminal arrives, transfer the NG2 connection and the GN3 connection of the second terminal in the NR system to a corresponding base station in the second RAN after receiving a paging response message of the second terminal, and send, to the second base station, a notification message for notifying the second base station to release the connection of the second terminal and delete the user context information of the second terminal when the second terminal is in an inactive state in the NR system.

The above first core network further includes:

a third receiving unit, configured to receive a prompt message sent by a third terminal in a second RAN in an RRC connection setup process, where the prompt message is used to prompt a third base station in the first RAN, and the third base station is a base station that stores user context information of the third terminal in the NR system, and then the first core network further includes:

and a second processing unit, configured to transfer, according to the hint information, the control plane interface NG2 connection and the user plane interface GN3 connection of the third terminal in the NR system to a corresponding base station in a second RAN, and send, to the third base station, a notification message for notifying the third base station to release the connection of the third terminal and delete the user context information of the third terminal when the third terminal is in an inactive state in the NR system.

The RRC connection establishment procedure of the first core network is triggered by the third terminal when initiating the uplink signaling procedure or when initiating the uplink service procedure.

a first receiving unit, configured to receive a prompt message sent by a terminal in a second RAN in an RRC connection establishment procedure, where the prompt message is used to prompt a first base station in the first RAN, the first base station is a base station that stores user context information of the terminal in the NR system, and the second RAN is a RAN of an LTE system;

a first sending unit, configured to send, to a first base station, a notification message for notifying the first base station to release the connection of the terminal and delete the user context information when the terminal is in an inactive state in an NR system.

In the above first core network, the first receiving unit further receives the hint message forwarded by the EPC through an interface with the EPC of the LTE system.

An embodiment of the present invention further provides a first base station of a wireless access network of a new air interface NR system, including:

a paging unit, configured to initiate paging of a first terminal in an inactive state in a RAN-level location area RNA in a first RAN, where the first base station stores user context information of the second terminal in the inactive state in the NR system, and the first RAN is a RAN of a new air interface NR system;

a first sending unit, configured to send a paging failure message to a first core network of the NR system, where the paging failure message indicates that the first terminal cannot be paged in the RNA, if the first RAN cannot page the first terminal in the RNA.

The above first base station further includes:

a first receiving unit, configured to receive a notification message sent by a first core network, where the notification message is used to notify the first base station to continue to maintain the connection of the second terminal;

a first processing unit, configured to start a timer according to the notification message, maintain a connection of the second terminal in the NR system before the timer expires, retain user context information when the second terminal is in an inactive state in the NR system, and release the connection of the second terminal and delete the user context information when the second terminal is in the inactive state in the NR system after the timer expires.

The above first base station further includes:

a second receiving unit, configured to receive a notification message sent by a first core network, where the notification message is used to notify the first base station to release the connection of the second terminal and delete the user context information of the second terminal when the second terminal is in an inactive state in an NR system;

and the second processing unit is used for releasing the connection of the second terminal and deleting the user context information of the second terminal in an inactive state in the NR system according to the notification message.

a receiving unit, configured to receive a notification message sent by a first core network of the NR system, where the notification message is used to notify the first base station to release connection of a terminal and delete user context information of the terminal when the terminal is in an inactive state in the NR system;

and the releasing unit is used for releasing the connection of the terminal and deleting the user context information of the terminal in an inactive state in the NR system according to the notification message.

Compared with the prior art, the mobility management method between the wireless access networks, the core network device and the base station provided by the embodiment of the invention still keep the user context information of the terminal in the non-activated state in the NR system when the terminal in the non-activated state moves between different systems, and delete the user context information until certain conditions are met. The invention can realize the inter-RAT mobility management of the terminal in the non-activated state, solve the mobility problem among different systems and ensure that the terminal can work normally.

Drawings

FIG. 1 is a schematic diagram of a network architecture of a prior art next generation (NextGen) network;

FIG. 2 is a schematic diagram of inter-RAT network architecture for eLTE and NR of the prior art;

FIG. 3 is a schematic diagram of the inter-RAT network architecture of LTE and NR of the prior art;

fig. 4 is a flowchart illustrating a mobility management method according to an embodiment of the present invention when applied to a terminal;

fig. 5 is a flowchart illustrating a mobility management method applied to an NR core network according to an embodiment of the present invention;

fig. 6 is another flow chart illustrating a mobility management method according to an embodiment of the present invention when applied to an NR core network;

fig. 7 is a schematic flowchart illustrating a mobility management method according to an embodiment of the present invention when applied to an NR core network;

fig. 8 is a flowchart illustrating a mobility management method applied to an NR base station according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a terminal according to an embodiment of the present invention;

fig. 10 is another schematic structural diagram of a terminal according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of a core network of an NR system according to an embodiment of the present invention;

fig. 12 is another schematic structural diagram of a core network of the NR system according to the embodiment of the present invention;

fig. 13 is a schematic diagram of another structure of a core network of the NR system according to the embodiment of the present invention;

fig. 14 is a schematic structural diagram of a core network of an NR system according to an embodiment of the present invention;

fig. 15 is a schematic structural diagram of a base station of an NR system according to an embodiment of the present invention;

fig. 16 is another schematic structural diagram of a base station of an NR system according to an embodiment of the present invention;

fig. 17 is a schematic view of another structure of a base station of an NR system according to an embodiment of the present invention;

fig. 18 is a schematic structural diagram of a base station of an NR system according to an embodiment of the present invention;

fig. 19 is a schematic view of a scenario of example 1 according to an embodiment of the present invention;

fig. 20 is a scene diagram of example 5 according to an embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments. In the following description, specific details such as specific configurations and components are provided only to help the full understanding of the embodiments of the present invention. Thus, it will be apparent to those skilled in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

It should be appreciated that reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In various embodiments of the present invention, it should be understood that the sequence numbers of the following processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention. In addition, the terms "system" and "network" are often used interchangeably herein.

< example one >

The present embodiment explains the behavior at the terminal side with respect to the application scenarios shown in fig. 2 and 3.

An embodiment of the present invention provides a method for mobility management between RANs, which is applied to RANs based on different RATs, and specifically, the RANs include a first RAN and a second RAN, where the first RAN is a RAN of a new air interface NR system, and the second RAN may be a RAN of a 3G system or a 4G system, or may be a RAN of an LTE system or an LTE system. The following embodiments herein will be mainly described by taking an LTE system and an LTE system as examples. It should be noted that the second RAN of the embodiment of the present invention is not limited to the RAN of the LTE system and the LTE system.

Referring to fig. 4, a mobility management method according to an embodiment of the present invention, when being applied to a terminal side, includes the following steps:

step 41, the terminal in the inactive state detects that the terminal accesses to the second RAN from the first RAN.

Here, the first RAN is a RAN of an NR system, and the terminal enters an inactive state under the first RAN, and then the terminal may move to enter a second RAN based on a different RAT. The second RAN may be a RAN of a 3G/4G/LTE system. When the terminal moves to and accesses the second RAN, it may determine that the terminal has currently left the first RAN and accessed the second RAN based on a different RAT by reading a system message broadcast by a cell air interface, and the like.

And 42, the terminal switches the self state from the inactive state to an idle state, and continuously and locally retains the user context information when the terminal is in the inactive state in the NR system.

Here, after entering the second RAN, the terminal switches its state to an IDLE state (RRC-IDLE) since the inactive state will no longer be applicable to the second RAN, and continues to locally retain the user context information of the terminal in the inactive state in the NR system. Specifically, the context information may include one or more of the following information: radio resource configuration parameters, security parameters, UE capability parameters, etc.

Through the above steps, the embodiment of the present invention defines the behavior of the terminal in the inactive state after leaving the first RAN of the NR system and entering the second RAN based on a different RAT, so that the terminal can adopt an idle state in which the terminal can operate under the second RAN, and the terminal can subsequently operate normally.

In step 42, the terminal retains the user context information when it is in the inactive state in the NR system, so as to be quickly restored to the inactive state when it returns to the NR system. For example, when the terminal detects that the terminal re-accesses the first RAN, the terminal may switch its state back to the inactive state, and recover the user context information when the terminal is in the inactive state in the NR system. At this time, after switching the state of the terminal itself back to the inactive state, the terminal may initiate an RNA update process of a location area at RAN level to perform RNA update, so that the RAN network side node may find the UE.

After step 42 above, the terminal is camped in the second RAN in an idle state. Subsequent terminals may behave differently in the second RAN. For example, the terminal may initiate an uplink signaling procedure or an uplink traffic procedure, in which the terminal may need to establish an RRC connection with the network. The following describes the behavior of the terminal according to the embodiment of the present invention in the above process.

1) When the second RAN is a RAN of an lte system, after step 42, if the terminal in an idle state resides in the second RAN, and if the terminal initiates an uplink signaling process in the second RAN, in a process of triggering establishment of an RRC connection in the uplink signaling process, the terminal may send, to the network side, prompt information of the first base station, where the prompt information is stored with user context information when the terminal is in an inactive state in the NR system, where the prompt information may be a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station. The prompt information is provided to the network side, so that the network side can determine the first base station based on the prompt information and inform the first base station to delete the context information of the terminal. Specifically, the eNB of the lte may directly send the prompt message sent by the user to the NGC, and the NGC notifies the first base station to delete the context information of the terminal.

In addition, in the process of triggering establishment of RRC connection in the uplink signaling process, or after receiving a paging message sent by the network side after the uplink signaling process is finished, the terminal may also delete locally-retained user context information when the terminal is in an inactive state in the NR system.

2) When the second RAN is a RAN of an lte system, the terminal resides in the second RAN in an idle state after the above step 42. Subsequently, if the terminal initiates an uplink service process in the second RAN, in the process of triggering establishment of RRC connection in the uplink service process, the terminal may send, to the network side, a prompt message of the first base station, where the prompt message of the first base station stores user context information when the terminal is in an inactive state in the NR system, where the prompt message is a current terminal identifier of the terminal, an inactive state terminal identifier associated with the user context information, or an identifier of the first base station. The prompt information is provided to the network side, so that the network side can determine the first base station based on the prompt information and inform the first base station to delete the context information of the terminal. Specifically, the eNB of the lte may directly send the prompt message sent by the user to the NGC, and the NGC notifies the first base station to delete the context information of the terminal.

In addition, in the process of triggering establishment of RRC connection in the uplink service process, the terminal may also delete locally-reserved user context information when the terminal is in an inactive state in the NR system.

3) When the second RAN is a RAN of the LTE system, the terminal resides in the second RAN in an idle state after the above step 42. And subsequently, if the terminal initiates an RRC connection establishment process, the terminal deletes locally-reserved user context information when the terminal is in an inactive state in the NR system, and sends prompt information of the first base station, which stores the user context information when the terminal is in the inactive state in the NR system, to the network side, wherein the prompt information is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station. The prompt information is provided to the network side, so that the network side can determine the first base station based on the prompt information and inform the first base station to delete the context information of the terminal. Specifically, the LTE base station eNB may send the prompt information sent by the user to the EPC, and the EPC forwards the prompt information to the NGC, so that the NGC notifies the first base station to delete the context information of the terminal.

As another implementation manner, in the embodiment of the present invention, a valid time timer for the user context information may be further set, where the timer triggers the terminal and the network side to delete the user context information when the terminal is in the inactive state in the NR system, based on a predetermined timeout time, after the timeout time is reached or exceeded.

The following describes the behavior of the terminal when the timer is used in the embodiment of the present invention.

After the step 42, the terminal starts a timer configured in advance by the NR system after the step of switching the state of the terminal from the inactive state to the idle state. Before the timer is overtime, if the terminal detects that the terminal is accessed back to the first RAN again, the timer is stopped, the state of the terminal is switched back to the inactive state, and the user context information of the terminal in the inactive state in the NR system is recovered. And after the timer is overtime, the terminal deletes the locally-reserved user context information when the terminal is in an inactive state in the NR system.

Upon starting the timer and residing in the second RAN in an idle state, the terminal may behave differently in the second RAN before the timer expires. For example, the terminal may initiate an uplink signaling procedure or an uplink traffic procedure, in which the terminal may need to establish an RRC connection with the network. The following describes the behavior of the terminal according to the embodiment of the present invention in the above process.

1) When the second RAN is a RAN of an lte system, after step 42, the terminal resides in the second RAN in an idle state, and before the timer expires, if the terminal initiates an uplink signaling process in the second RAN, in a process of triggering establishment of an RRC connection in the uplink signaling process, the terminal sends, to the network side, prompt information of the first base station, where the prompt information is user context information when the terminal is in an inactive state in the NR system, where the prompt information is a current terminal identifier of the terminal, an inactive state terminal identifier associated with the user context information, or an identifier of the first base station. The prompt information is provided to the network side, so that the network side can determine the first base station based on the prompt information and inform the first base station to delete the context information of the terminal. Specifically, the eNB of the lte may directly send the prompt message sent by the user to the NGC, and the NGC notifies the first base station to delete the context information of the terminal.

In addition, before the timer is overtime, in the process of triggering and establishing RRC connection in the uplink signaling process, or after a paging message sent by a network side is received after the uplink signaling process is finished, the terminal deletes locally-reserved user context information when the terminal is in an inactive state in an NR system.

2) When the second RAN is a RAN of an lte system, after step 42, the terminal resides in the second RAN in an idle state, and before the timer expires, if the terminal initiates an uplink service process in the second RAN, in a process of triggering establishment of an RRC connection in the uplink service process, the terminal sends, to a network side, prompt information of a first base station that stores user context information when the terminal is in an inactive state in the NR system, where the prompt information is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station. Specifically, the eNB of the lte may directly send the prompt message sent by the user to the NGC, and the NGC notifies the first base station to delete the context information of the terminal.

In addition, before the timer is overtime, in the process of triggering and establishing the RRC connection in the uplink service process, the terminal deletes the locally-reserved user context information when the terminal is in an inactive state in the NR system.

3) When the second RAN is a RAN of an LTE system, after step 42, the terminal resides in the second RAN in an idle state, and before the timer expires, if the terminal initiates an RRC connection establishment procedure, the terminal deletes locally-retained user context information when the terminal is in an inactive state in the NR system, and sends a prompt message of the first base station, which stores the user context information when the terminal is in the inactive state in the NR system, to the network side, where the prompt message is a current terminal identifier of the terminal, or an inactive state terminal identifier associated with the user context information, or an identifier of the first base station. Specifically, the LTE base station eNB may send the prompt information sent by the user to the EPC, and the EPC forwards the prompt information to the NGC, so that the NGC notifies the first base station to delete the context information of the terminal.

The above describes a mobility management method after the terminal in the inactive state enters another RAN. The above mobility management method will be further explained from the core network side of the NR system hereinafter.

< example two >

This embodiment explains the core network behavior on the NR side with respect to the application scenario shown in fig. 2.

Referring to fig. 5, an embodiment of the present invention provides a method for mobility management between radio access networks RAN, where the RAN includes a first RAN and a second RAN. Here, the first RAN is a RAN of an NR system, and the second RAN is a RAN of lte. The mobility management method is applied to a first core network side of an NR system and comprises the following steps:

step 51, the first core network of the NR system receives a paging failure message sent when a first base station in a first RAN cannot page an inactive first terminal in a RAN-level location area RNA, where the first base station is a base station that stores user context information of the first terminal in the NR system.

Step 52, the first core network initiates paging to the first terminal in a location area TA at core network level.

In step 51, when paging is performed for an inactive terminal, the first base station storing the user context information of the first terminal in the NR system sends notification messages (notification) to all cells in the RNA region of the first terminal to search for the UE. If the paging fails, indicating that the first terminal may leave the first RAN, the first core network further initiates paging of said first terminal within a core network level location area, TA, step 52.

Through the above steps, paging for the first terminal in an inactive state may be performed after the first terminal leaves the first RAN.

As described above, after a terminal in an inactive state (here, it is assumed that the terminal is a second terminal) leaves a first RAN and accesses a second RAN, the second terminal may initiate an uplink signaling process, and in an RRC connection establishment process triggered by the uplink signaling process, the second terminal may send a prompt message to a network side, where the prompt message is used to instruct the network side to store a base station having user context information of the terminal in an NR system. The following describes the behavior of the first core network in the above process.

The first core network of the NR system according to the embodiment of the present invention may further receive a prompt message sent by a second terminal in a second RAN in an RRC connection setup process triggered in an uplink signaling process, where the prompt message is used to prompt a second base station in the first RAN, and the second base station is a base station that stores user context information of the second terminal in the NR system.

After receiving the prompt message, the first core network may learn that the second terminal has left the first RAN and entered the second RAN, and at this time, the first core network continues to maintain the connection between the control plane interface NG2 and the user plane interface GN3 of the second terminal in the NR system according to the prompt message, and sends a notification message to the second base station to notify the second base station to continue to maintain the connection of the second terminal. Subsequently, after the uplink signaling process of the second terminal is finished, the first core network may release the connection between the second terminal and the lte system.

Subsequently, when the downlink traffic of the second terminal arrives, the first core network may directly page in the second RAN of the lte system, and after receiving a paging response message of the second terminal, transfer the NG2 connection and the GN3 connection of the second terminal in the NR system from the first base station to a corresponding base station (Pathswitch) in the second RAN, and send a notification message to the second base station for notifying the second base station to release the connection of the second terminal and delete the user context information when the second terminal is in an inactive state in the NR system.

In this embodiment of the present invention, as another implementation manner, in an uplink signaling process initiated by the second terminal, if receiving the prompt information, the first core network learns that the second terminal has left the first RAN and entered the second RAN, at this time, the first core network may directly switch an interface path (Pathswitch) of the second terminal without waiting for a downlink service of the second terminal to arrive, that is, after receiving the prompt information, the first core network transfers an NG2 connection and a GN3 connection of the second terminal in the NR system to a corresponding base station (Pathswitch) in the second RAN, and sends a notification message to the second base station, where the notification message is used for notifying the second base station to release the connection of the second terminal and delete the user context information of the second terminal when the second terminal is in an inactive state in the NR system.

As described above, after leaving the first RAN and accessing the second RAN, the terminal in the inactive state (here, it is assumed that the terminal is a third terminal), the third terminal may initiate an uplink service process, and in the RRC connection establishment process triggered by the uplink service process, the third terminal may send a prompt message to the network side, where the prompt message is used to instruct the network side to store the base station having the user context information of the terminal in the NR system. The following describes the behavior of the first core network in the above process.

The first core network of the NR system according to the embodiment of the present invention may further receive a prompt message sent by a third terminal in a second RAN in an RRC connection setup process, where the prompt message is used to prompt a third base station in the first RAN, and the third base station is a base station that stores user context information of the third terminal in the NR system. Here, the RRC connection establishment procedure is triggered by the third terminal when initiating an uplink signaling procedure or when initiating an uplink service procedure.

After receiving the above-mentioned hint information, the first core network may transfer the connection between the control plane interface NG2 and the user plane interface GN3 of the third terminal in the NR system to the corresponding base station in the second RAN, and send a notification message to the third base station for notifying the third base station to release the connection of the third terminal and deleting the user context information of the third terminal when the third terminal is in an inactive state in the NR system.

< example three >

This embodiment explains the core network behavior on the NR side with respect to the application scenario shown in fig. 3.

Referring to fig. 6, a method for mobility management between radio access networks RAN according to an embodiment of the present invention includes a first RAN and a second RAN. Here, the first RAN is a RAN of an NR system, and the second RAN is a RAN of LTE. The mobility management method is applied to a first core network side of an NR system and comprises the following steps:

step 61, the first core network of the NR system receives a prompt message sent by the terminal in the second RAN during the RRC connection establishment process, where the prompt message is used to prompt the first base station in the first RAN, and the first base station is a base station that stores user context information of the terminal in the NR system.

Here, the RRC connection establishment procedure may be triggered when the first terminal initiates an uplink signaling procedure, or when the first terminal initiates an uplink service procedure, or may be triggered when the network side discovers a downlink signaling/service procedure. The first core network can receive the prompting message forwarded by the EPC through an interface between the first core network and the EPC of the LTE system.

Step 62, the first core network sends a notification message to the first base station according to the prompt message, where the notification message is used to notify the first base station to release the connection of the terminal and to delete the user context information when the terminal is in the inactive state in the NR system.

Through the above steps, after receiving the above prompt message forwarded by the EPC of the LTE system, the first core network may instruct the first base station to release the connection of the terminal and delete the user context information of the first terminal, thereby implementing mobility management after the terminal in the inactive state enters the RAN of LTE.

The above second and third embodiments are described about the behavior of the core network of the NR system. The processing of the embodiments of the present invention at the radio access network RAN side of the NR system will be further explained below.

< example four >

Referring to fig. 7, an embodiment of the present invention provides a method for mobility management between radio access networks RAN, where the RAN includes a first RAN and a second RAN. Here, the first RAN is a RAN of an NR system, and the second RAN is a RAN of lte. The mobility management method is applied to a first RAN side of an NR system and comprises the following steps:

step 71, a first base station in a first RAN initiates paging of a first terminal in an inactive state in a RAN-level location area RNA, and the first base station stores user context information of the first terminal in the inactive state in the NR system.

Step 72, if the first RAN cannot page the first terminal in the RNA, sending a paging failure message to the first core network of the NR system, where the paging failure message indicates that the first terminal cannot be paged in the RNA.

In the above steps, the first RAN fails to page the first terminal within the RNA, indicating that the first terminal may leave the first RAN. At this time, the first base station sends a paging failure message to the core network, so that the core network can page the first terminal in the TA, and mobility management of the inactive terminal after entering the RAN of the e.lte is realized.

In the embodiment of the present invention, if the first base station receives a notification message sent by the first core network, the notification message is used to notify the first base station to continue to maintain the connection of the second terminal.

< example five >

Referring to fig. 8, a method for mobility management between radio access networks RAN according to an embodiment of the present invention includes a first RAN and a second RAN. Here, the first RAN is a RAN of an NR system, and the second RAN is a RAN of LTE. The mobility management method is applied to a first RAN side of an NR system and comprises the following steps:

step 81, the first base station of the NR system receives a notification message sent by the first core network of the NR system, where the notification message is used to notify the first base station to release the connection of the terminal and delete the user context information when the terminal is in an inactive state in the NR system.

And step 82, the first base station releases the connection of the terminal and deletes the user context information when the terminal is in the inactive state in the NR system according to the notification message.

In the above steps, the first base station releases the connection of the terminal and deletes the user context information when the terminal is in the inactive state in the NR system directly according to the notification message, thereby implementing mobility management of the inactive terminal after entering the RAN of LTE.

< example six >

Based on the mobility management method provided in the above embodiment, this embodiment provides a terminal implementing the above method. Referring to fig. 9, the present embodiment provides a terminal, including:

a first detecting unit 91, configured to detect that the terminal is accessed from a first RAN to a second RAN when the terminal is in an inactive state, where the first RAN is a RAN of a new air interface NR system;

a first switching unit 92, configured to switch the self state from the inactive state to an idle state, and continue to locally retain the user context information when the terminal is in the inactive state in the NR system.

Here, the terminal may further include:

Here, the second RAN is a RAN of an lte system, and the terminal further includes:

Here, the terminal further includes:

Referring to fig. 10, the present embodiment provides another terminal, including: a processor 101; a memory 103 connected to the processor 101 through a bus interface, and a transceiver 102 connected to the processor 101 through a bus interface; the memory is used for storing programs and data used by the processor in executing operations; transmitting control commands and the like through the transceiver 102; when the processor calls and executes the programs and data stored in the memory, the following functional units are implemented:

Where in fig. 10 the bus architecture may include any number of interconnected buses and bridges, in particular one or more processors represented by processor 101 and various circuits of memory represented by memory 103, linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 102 may be a number of elements, including a transmitter and a transceiver, providing a means for communicating with various other apparatus over a transmission medium. The processor 101 is responsible for managing the bus architecture and general processing, and the memory 103 may store data used by the processor 101 in performing operations.

The processor 101 is responsible for managing the bus architecture and general processing, and the memory 103 may store data used by the processor 101 in performing operations.

< example seven >

Based on the mobility management method provided in the above embodiment, this embodiment provides core network equipment of an NR system that implements the above method. Referring to fig. 11, the present embodiment provides a first core network of a new air interface NR system, including:

a first receiving unit 111, configured to receive a paging failure message sent when a first base station in a first RAN cannot page an inactive first terminal in a RAN-level location area RNA, where the first base station is a base station that stores user context information of the first terminal in the NR system, and the first RAN is a RAN of a new air interface NR system.

A first paging unit 112, configured to initiate paging for the first terminal in a location area TA at a core network level.

Here, the first core network further includes:

Here, the RRC connection establishment procedure is triggered by the third terminal when initiating an uplink signaling procedure or when initiating an uplink service procedure.

Referring to fig. 12, this embodiment provides another implementation of a first core network of a new air interface NR system, including: a processor 121; a memory 123 connected to the processor 121 via a bus interface, and a transceiver 122 connected to the processor 121 via a bus interface; the memory is used for storing programs and data used by the processor in executing operations; transmit control commands and the like through the transceiver 122; when the processor calls and executes the programs and data stored in the memory, the following functional units are implemented:

a first receiving unit, configured to receive a paging failure message sent when a first base station in a first RAN cannot page a first terminal in an inactive state in a RAN-level location area RNA, where the first base station is a base station that stores user context information of the first terminal in the NR system, and the first RAN is a RAN of a new air interface NR system.

In fig. 12, among other things, the bus architecture may include any number of interconnected buses and bridges with various circuits of memory represented by memory 123 and one or more processors represented by processor 121 linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 122 may be a plurality of elements, including a transmitter and a transceiver, providing a means for communicating with various other apparatus over a transmission medium. The processor 121 is responsible for managing a bus architecture and general processing, and the memory 123 may store data used by the processor 121 when performing operations.

The processor 121 is responsible for managing a bus architecture and general processing, and the memory 123 may store data used by the processor 121 when performing operations.

Referring to fig. 13, the present embodiment provides a first core network of another new air interface NR system, including:

a first receiving unit 131, configured to receive a prompt message sent by a terminal in a second RAN in an RRC connection setup process, where the prompt message is used to prompt a first base station in a first RAN, the first base station is a base station that stores user context information of the terminal in the NR system, the first RAN is a RAN of the NR system, and the second RAN is a RAN of an LTE system.

A first sending unit 132, configured to send a notification message to the first base station, the notification message being used to notify the first base station to release the connection of the terminal and delete the user context information when the terminal is in an inactive state in the NR system.

Here, the first receiving unit 131 further receives the hint message forwarded by the EPC through an interface with the EPC of the LTE system.

Referring to fig. 14, this embodiment provides another implementation of a first core network of a new air interface NR system, including: a processor 141; a memory 143 connected to the processor 141 through a bus interface, and a transceiver 142 connected to the processor 141 through a bus interface; the memory is used for storing programs and data used by the processor in executing operations; transmit control commands, etc. via the transceiver 142; when the processor calls and executes the programs and data stored in the memory, the following functional units are implemented:

a first receiving unit, configured to receive a prompt message sent by a terminal in a second RAN in an RRC connection setup process, where the prompt message is used to prompt a first base station in the first RAN, the first base station is a base station that stores user context information of the terminal in the NR system, and the second RAN is a RAN of an LTE system.

Wherein in fig. 14, the bus architecture may include any number of interconnected buses and bridges, with one or more processors represented by processor 141 and various circuits of memory represented by memory 143 being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 142 may be a number of elements, including a transmitter and a transceiver, providing a means for communicating with various other apparatus over a transmission medium. The processor 141 is responsible for managing a bus architecture and general processing, and the memory 143 may store data used by the processor 141 in performing operations.

The processor 141 is responsible for managing a bus architecture and general processing, and the memory 143 may store data used by the processor 141 in performing operations.

< example eight >

Based on the mobility management method provided in the above embodiment, the present embodiment provides a base station of an NR system that implements the above method. Referring to fig. 15, the present embodiment provides a first base station of a new air interface NR system, including:

a paging unit 151, configured to initiate paging of a first terminal in an inactive state in a RAN-level location area RNA in a first RAN, where the first base station stores user context information of the first terminal in the inactive state in the NR system, and the first RAN is a RAN of a new air interface NR system.

A first sending unit 152, configured to send a paging failure message to the first core network of the NR system, where the paging failure message indicates that the first terminal cannot be paged in the RNA, if the first RAN cannot page the first terminal in the RNA.

Here, the first base station further includes:

Referring to fig. 16, this embodiment provides another implementation of a first core network of a new air interface NR system, including: a processor 161; a memory 163 connected to the processor 161 through a bus interface, and a transceiver 162 connected to the processor 161 through a bus interface; the memory is used for storing programs and data used by the processor in executing operations; transmit control commands and the like through the transceiver 162; when the processor calls and executes the programs and data stored in the memory, the following functional units are implemented:

a paging unit, configured to initiate paging of a first terminal in an inactive state in a RAN-level location area RNA in a first RAN, where the first base station stores user context information of the second terminal in the inactive state in the NR system, and the first RAN is a RAN of a new air interface NR system.

In fig. 16, among other things, the bus architecture may include any number of interconnected buses and bridges with one or more processors, represented by processor 161, and various circuits, represented by memory 163, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 162 may be a number of elements, including a transmitter and a transceiver, providing a means for communicating with various other apparatus over a transmission medium. The processor 161 is responsible for managing the bus architecture and general processing, and the memory 163 may store data used by the processor 161 in performing operations.

The processor 161 is responsible for managing the bus architecture and general processing, and the memory 163 may store data used by the processor 161 in performing operations.

Referring to fig. 17, a first base station of another new air interface NR system according to an embodiment of the present invention includes:

a receiving unit 171, configured to receive a notification message sent by a first core network of the NR system, where the notification message is used to notify the first base station to release the connection of the terminal and delete the user context information when the terminal is in an inactive state in the NR system;

a releasing unit 172, configured to release the connection of the terminal and delete the user context information when the terminal is in an inactive state in the NR system according to the notification message.

Referring to fig. 18, another implementation of the first base station of the new air interface NR system according to another embodiment of the present invention includes: a processor 181; a memory 183 connected to the processor 181 through a bus interface, and a transceiver 182 connected to the processor 181 through a bus interface; the memory is used for storing programs and data used by the processor in executing operations; transmit control commands and the like through the transceiver 182; when the processor calls and executes the programs and data stored in the memory, the following functional units are implemented:

Wherein in fig. 18 the bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 181, and various circuits, represented by memory 183, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 182 may be a number of elements, including a transmitter and a transceiver, providing a means for communicating with various other apparatus over a transmission medium. The processor 181 is responsible for managing the bus architecture and general processing, and the memory 183 may store data used by the processor 181 in performing operations.

The processor 181 is responsible for managing the bus architecture and general processing, and the memory 183 may store data used by the processor 181 in performing operations.

The above describes a mobility management method, and a core network and a base station implementing the method according to the embodiment of the present invention. The invention will be further described by way of a number of examples of complete flow.

< example 1>

The scenario of example 1 is: an inactive terminal (UE) enters the RAN of the eLTE network from the RAN of the NR, and the UE initiates uplink signaling in the eLTE network.

The network architecture of example 1 is as shown in fig. 2 in the background art, and the specific scenario is as shown in fig. 19, when the NR enters an inactive state, both the gNB and the UE keep a set of user context information (NR UE context) when the UE is in an inactive state in the NR system. Meanwhile, the gNB may configure the UE with a validity time timer (timer) of the NR UE context. Thereafter, the UE enters the lte network from the NR network. This timer is started once the UE enters the lte. If the gNB does not configure the timer or configures the timer to infinity, the UE keeps the NR UE context.

After entering the eLTE network, the UE enters an idle state, the UE context of the NR is still reserved, and a valid timer (if any) is started. Before the validity timer (if any) times out, if the UE goes back to NR, inactive state is restored directly and NR UE context is restored. Optionally, the UE makes one RNA update at NR. After the timer expires, the UE deletes the NR UE context.

During the operation of the timer (if any), the UE initiates a TAU process to trigger an RRC connection establishment process, and in the connection establishment process, the UE notifies the network of the current UE identity (such as S-TMSI), or an inactive UE ID associated with the NR UE context or a gNB identity storing the NR UE context, so that the NGC knows that the UE has entered the eLTE network.

After the NGC knows that the UE has entered the eLTE network, the NGC can continue to keep the connection between the gNB and the NGC and inform the gNB to keep the connection (the NGC finds the gNB based on the UE identification, or inactive UE ID, or the gNB identification storing the NR UE context), the NR base station starts an effective time timer (timer) of the NR UE context, the NR UE context is kept during the running period of the timer, and the NR UE context is deleted after the timer is overtime. And when the signaling process is finished, the NGC releases the connection of the UE in the eLTE. If downlink traffic is sent to the UE subsequently, and the NGC knows that the UE does not return to the NR, the NGC pages in eLTE directly, and after the UE responds to the paging, the NG2 and NG3 interfaces of the UE are transferred from the gNB to the eLTE base station (for example, the gNB establishes a relevant interface and notifies the gNB to release the previous interface and delete the NR UE context). After receiving the page, the UE stops the NR UE context timer (if any) and deletes the NR UE context.

After the NGC knows that the UE has entered the lte network, another implementation manner is: the NGC directly transfers the NG2 and NG3 interfaces of the UE from the gNB to the lte base station (e.g., establishes a related interface at the lte and informs the gNB to release the previous interface and NR UEcontext). And when the UE initiates RRC connection establishment, the NR UE context timer (if any) is stopped, and the NRUE context is deleted.

< example 2>

The scenario of example 2 is: inactive UE enters RAN of the lte network from RAN of NR, and UE initiates uplink service in the lte network.

The network architecture and specific scenario of example 2 are the same as example 1. The UE enters inactive state in NR, and a set of NR UE context is reserved on both gNB and UE sides. Meanwhile, the gNB may configure a validity time timer (timer) of the NR UE context for the UE, and start the timer once the UE enters the lte. If the gNB does not configure the timer or configures the timer to infinity, the UE keeps the NR UE context.

After entering into eLTE network from NR network, UE in inactive state enters into idle state, UE context of NR is still reserved, and valid timer (if any) is started. Before the validity timer (if any) times out, if the UE returns to NR, the inactive state is directly recovered, and NR UE context is recovered, and optionally, the UE makes one RNA update at NR. After the timer expires, the UE deletes the NR UE context.

During the operation of the timer (if any), the UE initiates an uplink data transmission process, an RRC connection establishment process is triggered, the eLTE base station receives an RRC connection establishment request of the UE and establishes connection of the UE with the NGC, and then the NGC transfers NG2 and NG3 interfaces of the UE from the gNB to the eLTE base station. The UE stops the NR UE context timer (if any) and deletes the NR UE context when initiating the RRC connection setup.

< example 3>

The scenario of example 3 is: inactive UE enters eLTE network RAN from NR RAN, and the network initiates downlink signaling or downlink service

The network architecture and specific scenario of example 3 are the same as example 1. The UE enters inactive state in NR, and a set of NR UE context is reserved on both gNB and UE sides. Meanwhile, the gNB may configure a validity time timer (timer) of the NR UE context for the UE, and start the timer once the UE enters the lte. If the gNB does not configure the timer or configures the timer to infinity, the UE keeps the NR UE context.

And the UE in the inactive state enters the eLTE network from the NR network, the UE enters the idle state after entering the eLTE network, the UE context of the NR is still reserved, and a valid timer (if any) is started. Before the validity timer (if any) times out, if the UE returns to NR, the inactive state is directly recovered, and NR UE context is recovered, and optionally, the UE makes one RNA update at NR. After the timer expires, the UE deletes the NR UE context.

During the operation of the timer (if any), the UE does not initiate any uplink transmission in the lte network, the NGC still considers that the UE is in the NR network, at this time, if there is downlink traffic or signaling in the NR network to reach the gNB, the gNB is triggered to perform RAN-side paging, when the gNB cannot page the UE in the RAN range, the gNB notifies the NGC (optionally, the gNB deletes NR UE context), the NGC performs core network paging (paging in the TA range), the UE subsequently responds to the paging from the lte network, initiates an uplink process, and the uplink process may adopt the manner in example 1 or example 2.

< example 4>

The scenario of example 4 is: inactive UEs enter the lte network from NR without uplink and downlink traffic/signaling.

The network architecture and specific scenario of example 4 are the same as example 1. The UE enters inactive state in NR, and a set of NR UE context is reserved on both gNB and UE sides. Meanwhile, the gNB may configure a validity time timer (timer) of the NR UE context for the UE, and start the timer once the UE enters the lte. If the gNB does not configure the timer or configures the timer to infinity, the UE keeps the NR UE context.

And the UE in the inactive state enters the eLTE network from the NR network, the UE enters the idle state after entering the eLTE network, the UE context of the NR is still reserved, and a valid timer (if any) is started. During the operation of the valid timer (if any), the UE has no uplink and downlink service/signaling initiation in the eLTE network, and the subsequent UE returns to the NR network, then the UE directly enters an inactive state, recovers NR UE context and stops the timer. Optionally, the UE makes one RNA update at NR.

If the timer runs overtime when the UE is in the eLTE network, the UE deletes the NR UE context.

< example 5>

The scenario of example 5 is: inactive UE entering LTE network from NR

Example 5 as shown in fig. 3 in the background, a specific scenario is shown in fig. 20. The UE enters inactive state in NR, and a set of NR UE context is reserved on both gNB and UE sides. Meanwhile, the gNB may configure a validity time timer (timer) of the NR UE context for the UE, and start the timer once the UE enters LTE. If the gNB does not configure the timer or configures the timer to infinity, the UE keeps the NR UE context.

And the UE in the inactive state enters the LTE network from the NR network. After entering the LTE network, the UE enters an idle state, the UE context of the NR is still reserved, and a valid timer (if any) is started. The subsequent UE initiates RRC connection establishment, the UE informs the network of the current UE identity (e.g. S-TMSI), or inactive UE ID associated with NR UE context or gbb identity holding NR UE context, and at the same time the UE stops the NR UE context timer (if any) and deletes NR UE context. The EPC of the LTE informs the NGC of the entering of the UE into the LTE network, and the NGC finds the gNB storing the NR UE context based on the UE identity, inactive UE ID or the gNB identity storing the NR UE context, informs the gNB to release the NR UE context and releases the connection of the UE in the NR network (comprising NG2 and NG3 interfaces).

To sum up, the mobility management method, the core network, and the base station according to the embodiments of the present invention, wherein after entering an LTE/LTE network from an NR network, an inactive UE context is still retained until some conditions are met, and an NRUE context is not deleted, where the specific conditions may include that the UE initiates RRC connection establishment in the LTE/LTE network, receives a page, or an NRUE context validity timer expires. Through the processing, the embodiment of the invention realizes the inter-RAT mobility management of inactive UE, can solve the mobility problem among different systems, and enables the terminal to work normally.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method for mobility management between Radio Access Networks (RANs) includes a first RAN and a second RAN, wherein the first RAN is a RAN of a new air interface (NR) system, and the method includes:

the terminal switches the self state from the non-activated state to an idle state, and continuously retains the user context information of the terminal in the non-activated state in the NR system;

after the step of switching the self state from the inactive state to the idle state by the terminal, the method further includes:

the terminal starts a timer configured by an NR system in advance;

2. The method of claim 1, wherein after the step of the terminal switching its state from the inactive state to an idle state, the method further comprises:

3. The method of claim 1, wherein the second RAN is a RAN of an lte system, and wherein after the step of the terminal switching its state from the inactive state to an idle state, if the terminal initiates an uplink signaling procedure in the second RAN, the method further comprises:

4. The method of claim 1, wherein the second RAN is a RAN of an lte system, and wherein after the step of the terminal switching its state from the inactive state to an idle state, if the terminal initiates an uplink traffic procedure in the second RAN, the method further comprises:

5. The method of claim 1, wherein the second RAN is a RAN of an LTE system, and wherein after the step of the terminal switching its state from the inactive state to an idle state, the method further comprises:

6. The method of claim 1, wherein the second RAN is a RAN of an lte system, and wherein after the step of the terminal switching its state from the inactive state to an idle state, if the terminal initiates an uplink signaling procedure in the second RAN before the timer expires, the method further comprises:

7. The method of claim 1, wherein the second RAN is a RAN of an lte system, and wherein after the step of the terminal switching its state from the inactive state to an idle state, if the terminal initiates an uplink traffic procedure in the second RAN before the timer expires, the method further comprises:

8. The method of claim 1, wherein the second RAN is a RAN of an LTE system, and wherein after the step of the terminal switching its state from the inactive state to an idle state, the method further comprises:

9. The method of claim 2, wherein after the step of switching the self state back to the inactive state, the method further comprises:

10. A terminal, characterized in that the terminal comprises:

a first switching unit, configured to switch a self state from the inactive state to an idle state by the terminal, and continue to locally reserve user context information when the terminal is in the inactive state in the NR system;

11. The terminal of claim 10, further comprising:

12. The terminal of claim 10, wherein the second RAN is a RAN of an lte system, the terminal further comprising:

13. The terminal of claim 10, wherein the second RAN is a RAN of an lte system, the terminal further comprising:

14. The terminal of claim 10, wherein the second RAN is a RAN of an LTE system, the terminal further comprising:

15. The terminal of claim 10, wherein the second RAN is a RAN of an lte system, the terminal further comprising:

16. The terminal of claim 10, wherein the second RAN is a RAN of an lte system, the terminal further comprising:

17. The terminal of claim 10, wherein the second RAN is a RAN of an LTE system, the terminal further comprising:

18. The terminal of claim 11, wherein the terminal further comprises: