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WO2018028698A1 - 切换方法、基站及通信系统 - Google Patents

切换方法、基站及通信系统 Download PDF

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Publication number
WO2018028698A1
WO2018028698A1 PCT/CN2017/097221 CN2017097221W WO2018028698A1 WO 2018028698 A1 WO2018028698 A1 WO 2018028698A1 CN 2017097221 W CN2017097221 W CN 2017097221W WO 2018028698 A1 WO2018028698 A1 WO 2018028698A1
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WO
WIPO (PCT)
Prior art keywords
base station
core network
target
source
network device
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2017/097221
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English (en)
French (fr)
Inventor
石小丽
戴明增
张宏卓
曾清海
王瑞
郭轶
刘蕾
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huawei Technologies Co Ltd
Original Assignee
Huawei Technologies Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huawei Technologies Co Ltd filed Critical Huawei Technologies Co Ltd
Priority to EP17838828.6A priority Critical patent/EP3477994B1/en
Publication of WO2018028698A1 publication Critical patent/WO2018028698A1/zh
Priority to US16/254,829 priority patent/US11323920B2/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/0005—Control or signalling for completing the hand-off
    • H04W36/0055—Transmission or use of information for re-establishing the radio link
    • H04W36/0066—Transmission or use of information for re-establishing the radio link of control information between different types of networks in order to establish a new radio link in the target network
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/0005—Control or signalling for completing the hand-off
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/0005—Control or signalling for completing the hand-off
    • H04W36/0011—Control or signalling for completing the hand-off for data sessions of end-to-end connection
    • H04W36/0022—Control or signalling for completing the hand-off for data sessions of end-to-end connection for transferring data sessions between adjacent core network technologies
    • H04W36/00222—Control or signalling for completing the hand-off for data sessions of end-to-end connection for transferring data sessions between adjacent core network technologies between different packet switched [PS] network technologies, e.g. transferring data sessions between LTE and WLAN or LTE and 5G
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/0005—Control or signalling for completing the hand-off
    • H04W36/0055—Transmission or use of information for re-establishing the radio link
    • H04W36/0061—Transmission or use of information for re-establishing the radio link of neighbour cell information
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/08—Reselecting an access point
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/12—Reselecting a serving backbone network switching or routing node
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/14—Reselecting a network or an air interface
    • H04W36/142—Reselecting a network or an air interface over the same radio air interface technology
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/34—Reselection control
    • H04W36/38—Reselection control by fixed network equipment

Definitions

  • Embodiments of the present invention relate to a wireless communication technology, and in particular, to a handover method, a base station, and a communication system.
  • New RAT or NR or NRAT new radio access technologies
  • New RAT or NR or NRAT new radio access technologies
  • NR or NRAT new radio access technology
  • An evolved LTE base station (eLTE eNB) is generated on the basis of a base station device (evolved NodeB, eNB) in the Long Term Evolution (LTE) access network, in combination with the New RAT. .
  • the eLTE eNB is a base station device in the new radio access network, and can be simultaneously connected to a core network corresponding to the existing radio access network, such as an evolved packet core (EPC), and a corresponding corresponding to the new radio access network.
  • Core network such as next generation core (NG-Core)
  • CN relocation Complete core network relocation
  • the source core network when performing an inter-RAT handover, identifies the target core network through the tracking area identifier of the target core network, thereby completing the handover.
  • the source core network in the process of switching from the core network corresponding to the existing radio access network to the core network corresponding to the new radio access network, the source core network cannot accurately find the target core network according to the tracking area identifier, and thus cannot complete the core network migration process. .
  • the embodiment of the invention provides a handover method, a base station and a communication system, which enable the source core network to accurately locate the target core network.
  • an embodiment of the present invention provides a handover method, including: a source base station determines to switch a user equipment (UE) to a target base station, where the source base station is connected to a source core network device, The target base station is respectively connected to the source core network device and the target core network device; subsequently, the source base station sends a handover request message to the source core network device, where the handover request message includes identification information of the target core network device.
  • the handover request message is used to indicate that the source core network device and the target core network device perform a core network migration process.
  • the handover method provided by the embodiment of the present invention may be applicable to a handover scenario in which the target base station supports both the source core network and the target core network, and the source core network device can accurately identify the target by carrying the identification information of the target core network device in the handover request message.
  • the core network equipment completes the core network migration and improves the switching efficiency.
  • the method further includes: the source base station acquiring configuration information of the target base station from the target base station, where the configuration information includes connecting to the target base station The identification information of the core network device and/or the indication information indicating that the target base station has a connection with the core network device.
  • the identification information of the target core network device includes the identifier information and/or the connection indication information of the target core network, where the connection indication information is used to indicate that the target base station has a connection with the target core network.
  • the configuration information includes: connecting to the target base station Any one of the identification information of the core network device and the indication information indicating that the target base station is connected to the core network device, and the location area identifier allocated by the core network device connected to the target base station to the target base station .
  • the identification information of the target core network device includes any combination of one or more of the following: identification information of the target core network, connection indication information, and allocation by the target core network device to the target base station. a location area identifier, where the connection indication information is used to indicate that the target base station has a connection with the target core network.
  • the acquiring, by the source base station, configuration information of the target base station from the target base station includes: the source base station sending an interface connection establishment request message to the target base station; The source base station receives an interface connection establishment response message from the target base station, where the connection establishment response message includes configuration information of the target base station.
  • the interface setup request message includes configuration information of the source base station.
  • the method further includes: the source base station acquiring UE capability information; the source base station may determine, according to the UE capability information and configuration information of the target base station, The core network device and the target core network device perform a core network migration process.
  • the source base station may send a core network migration indication message to the source core network device, where the source core network device initiates the core network migration process, including positioning the target core network device, and sending the forward weight to the target core network device. Configure the message.
  • the base stations of the two parties complete the interaction of the configuration information, and then the source base station quickly determines the core network migration between the source core network device and the target core network device, and the overall handover The process is simple and efficient.
  • the method further includes: the source base station sending an interface switch request message to the target base station, where the interface switch request message includes UE capability information, so that the Determining, by the target base station, the core network migration process by the source core network device and the target core network device according to the UE capability information and the configuration information of the target base station; the source base station receiving an interface switching request response from the target base station And the interface switching request response message is used to indicate that the source base station sends the handover request message to the source core network device.
  • the UE capability information is used to indicate that the UE supports both the source base station standard service and the target base station standard service.
  • the target base station determines whether to perform the core network migration process, and then exchanges the configuration information of the base station in the handover process, and completes the handover process of the UE. Since the target base station can obtain the information of the target core network in time, the decision accuracy is high.
  • an embodiment of the present invention provides a base station, where the base station has a function of implementing behavior of a source base station in the foregoing handover method.
  • the functions may be implemented by hardware or by corresponding software implemented by hardware.
  • the hardware or software includes one or more modules corresponding to the functions described above.
  • the base station includes multiple function modules, which are used to implement any one of the foregoing first aspects, so that the source core network device can accurately identify the target core network device, and further Complete core network migration to improve switching efficiency.
  • the base station includes a processor, a transceiver, and a communication module, where the processor is configured to support the base station to perform a corresponding function in the foregoing handover method.
  • the transceiver is configured to support communication between the base station and the UE, and the communication module is configured to support communication between the base station and other network devices, and send information or instructions involved in the foregoing handover method to the network device.
  • the base station may also include a memory for coupling with the processor, which stores program instructions and data necessary for the base station to perform the above described switching method.
  • an embodiment of the present invention provides a handover method, including: a target base station determining a target core network device; the target base station sending an indication message to a source base station, where the indication message is used by the source core network device and the Target core
  • the core network device performs a core network migration process, wherein the source base station is connected to the source core network device, and the target base station is respectively connected to the source core network device and the target core network device.
  • the indication information may be an interface switching request response message or an identifier of the target core network to protect an independent indicator bit.
  • the embodiment of the present invention provides a base station, where the base station has a function of implementing behavior of a target base station in the foregoing handover method.
  • the functions may be implemented by hardware or by corresponding software implemented by hardware.
  • the hardware or software includes one or more modules corresponding to the functions described above.
  • an embodiment of the present invention provides a handover method, including: a source core network device receives a handover request message from a source base station, where the handover request message includes identification information of a target core network device; and the source core network device Performing a core network migration process with the target core network device according to the handover request message.
  • the source core network device performs a core network migration process with the target core network device according to the handover request message, where the source core network device is configured according to the target core network.
  • the identification information of the device is searched for the target core network device.
  • the source core network device sends a forward reconfiguration request message to the target core network device, and indicates that the target core network device creates a bearer resource for the UE.
  • the embodiment of the present invention provides a core network device, where the core network device has a function of implementing the behavior of the source core network device in the foregoing handover method.
  • the functions may be implemented by hardware or by corresponding software implemented by hardware.
  • the hardware or software includes one or more modules corresponding to the functions described above.
  • the embodiment of the present invention provides a communication system, where the system includes the source base station, the target base station, and the core network device, that is, the source core network device, in the second aspect, where the source The base station is connected to the source core network device, and the target base station is connected to the source core network device.
  • the system further includes another core network device connected to the target base station, that is, the target core network device.
  • the target base station in the communication system may be the base station in the fourth aspect, or may be another base station.
  • an embodiment of the present invention provides a computer storage medium for storing computer software instructions for a base station provided by the second aspect, which includes a program designed to execute the first aspect.
  • the embodiment of the present invention provides a computer storage medium for storing computer software instructions for a base station provided by the second aspect, which includes a program designed to execute the third aspect.
  • the source base station after determining that the UE is handed over to the target base station, the source base station sends a handover request message to the source core network device, where the handover request message includes identification information of the target core network device, where the handover request is performed.
  • the message is used to indicate that the source core network device and the target core network device perform a core network migration process.
  • the technical solution provided by the embodiment of the present invention can be applied to the target base station supporting the handover scenario of the source core network and the target core network, and carrying the identification information of the target core network device in the handover request message, so that the source core network device can accurately identify the target. Core network equipment.
  • FIG. 1 is a schematic diagram of an application scenario according to an embodiment of the present invention.
  • FIG. 2 is a schematic flowchart of a handover method according to an embodiment of the present invention.
  • FIG. 3 is a schematic diagram of a signaling process of a handover method according to an embodiment of the present invention.
  • FIG. 4 is a schematic diagram of a signaling flow of a method for determining a core network migration according to an embodiment of the present invention
  • FIG. 5 is a schematic structural diagram of a base station according to an embodiment of the present disclosure.
  • FIG. 6 is a schematic structural diagram of a base station according to an embodiment of the present invention.
  • FIG. 7 is a schematic structural diagram of another base station according to an embodiment of the present disclosure.
  • FIG. 8 is a schematic structural diagram of a core network device according to an embodiment of the present disclosure.
  • FIG. 9 is a schematic structural diagram of a core network device according to an embodiment of the present invention.
  • FIG. 10 is a schematic diagram of a communication system according to an embodiment of the present invention.
  • the technology described in the embodiments of the present invention can be used in various communication systems, such as 2G systems such as Global System for Mobile communications (GSM), and Wideband Code Division Multiple Access Wireless (WCDMA) systems.
  • 4G systems such as 3G systems and LTE systems
  • 5G (the fifth generation) system such as the communication system of the new radio access technology (New RAT), and a communication network in which a wireless local area network (WLAN) and a cellular network are integrated.
  • the communication system using the New RAT includes an evolved LTE system, or another communication system using the 5G communication technology, and the like.
  • the evolved packet core (EPC) described in the embodiment of the present invention is a core network of the LTE system, and includes a mobility management entity (MME) responsible for signaling processing, and a service responsible for data processing.
  • MME mobility management entity
  • a device such as a serving gateway (S-GW) or a packet data gateway (PDN).
  • S-GW serving gateway
  • PDN packet data gateway
  • the NG-Core (hereinafter referred to as NGC) described in the embodiment of the present invention may also be referred to as a new core network (New Core), or a 5G New Core, or a 5G Core, etc., and refers to a radio access network using NEW RAT (below The core network connected to the "NEW RAT access network" for short.
  • New Core new core network
  • 5G New Core 5G New Core
  • 5G Core 5G Core
  • the NG RAN may include at least two types of base stations, one of which adopts a next generation access technology (hereinafter referred to as "A base station (hereinafter referred to as "gNB) of New Radio, NR”), and an eLTE eNB enhanced based on the original LTE eNB.
  • a base station hereinafter referred to as "gNB) of New Radio, NR
  • eLTE eNB enhanced based on the original LTE eNB.
  • NG-Core is set up independently of the existing core network.
  • Specific devices in the NG-Core can refer to devices in the EPC, for example, devices that have functions similar to MME and S-GW, or all functional entities can be integrated into one device, or multiple devices per device and per device.
  • One or more core network functions are provided, and the embodiment of the present invention does not specifically limit this.
  • the UE involved in the embodiments of the present invention may include a handheld device having a wireless communication function, an in-vehicle device, a wearable device, a computing device, or other processing device connected to the wireless modem, and various forms of user equipment, mobile stations (mobile Station, MS), terminal, terminal equipment, etc., are referred to as “user equipment” or “UE” in this application for convenience of description.
  • the embodiment of the present invention defines that the unidirectional communication link of the base station to the UE is a downlink, and the unidirectional communication link of the UE to the base station is an uplink.
  • the resources described in the embodiments of the present invention are transmission resources, including time domain resources and frequency domain resources, and can be used to carry data or signaling in an uplink communication process or a downlink communication process. That is, the resource in the embodiment of the present invention may be an uplink resource allocated by the base station to the UE, and used for the UE to send uplink data, or may be a downlink resource allocated by the base station to the UE, for the UE to receive downlink data.
  • Multiple appearing in the embodiments of the present invention means two or more.
  • the descriptions of the first, second, and the like appearing in the embodiments of the present invention are only used for the purpose of illustrating and distinguishing the description objects, and there is no order, nor does it mean that the number of devices in the embodiment of the present invention is particularly limited, and the present invention cannot be constructed. Any limitations of the embodiments.
  • connection refers to various connection modes such as direct connection or indirect connection, for example, connecting different devices through a communication interface without any limitation.
  • the "network” and the “system” appearing in the embodiments of the present invention express the same concept, and the communication system is a communication network.
  • FIG. 1 is a schematic diagram of an application scenario according to an embodiment of the present invention.
  • the communication system shown in FIG. 1 includes a base station device (hereinafter referred to as an LTE eNB) in an LTE access network, and a base station device (hereinafter referred to as an eLTE eNB) in a NEW RAT access network,
  • the LTE eNB is connected to the EPC through the S1 interface
  • the eLTE eNB is connected to the EPC through the S1 interface
  • the NG-Core is connected through the NG1 interface
  • a communication interface may exist between the LTE eNB and the eLTE eNB, for example, the X2 interface shown in the figure. Used to exchange information between base stations.
  • the eLTE eNB is a base station device that is evolved on an eNB basis, and supports simultaneous connection of different types of core networks. It can be understood that the S1 interface or the NG1 interface is shown. In actual applications, the eLTE eNB can also be connected to the EPC or the NG-Core in other manners.
  • the UE will switch the accessed base station during the mobile process to obtain the best communication service.
  • the UE accessing the LTE eNB moves to the signal coverage of the eLTE eNB
  • the UE may initiate a handover procedure, and the LTE eNB switches to the eLTE eNB.
  • a core network relocation process, or a core network reconfiguration process is required to switch the context of the UE from the EPC to the NG-Core.
  • the source base station in the embodiment of the present invention refers to a base station device that the UE currently accesses or camps on, and the UE will switch from the base station device to another base station device, where the source base station may be a base transceiver station in GSM (Base a Transceiver Station (BTS) or a base station controller, which may also be a Node B (NodeB) or a Radio Network Controller (RNC) in a WCDMA system, and may be an evolved Node B in an LTE system.
  • GSM Base a Transceiver Station
  • NodeB Node B
  • RNC Radio Network Controller
  • the target base station in the embodiment of the present invention refers to a base station device to which the UE is to be handed over, and the target base station may be a base station device that supports two or more core networks, such as an eLTE eNB.
  • the source core network device in the embodiment of the present invention refers to a device that provides a core network service for a source base station.
  • the target core network device in the embodiment of the present invention refers to a device that provides a core network service for a target base station. It can be understood that both the source core network device and the target core network device can include one or more functional entities that are independently set or integrated.
  • the location area identifier allocated by the source core network may identify the core network to which the target base station belongs, and then determine the target core network.
  • the location area identifier of the target base station may be allocated by the source core network, or the source core network and the target core network may be assigned different location area identifiers, that is, The source core network and the target core network belong to the core network under different standards, and the core network under different standards allocates and maintains respective location area identifiers, or the source core network and the target core network may assign the same base station location identifier to the target base station.
  • the location area identifier used in the embodiment of the present invention is used to indicate a location area where the UE in an idle state is located, where the location area is composed of one or more cells, including a tracking area in the LTE system. Area, TA), a location area (LA) in the UMTS system, a moving area (MA) in the New RAT access network, and the like.
  • the system also called RAT
  • RAT usually has a one-to-one correspondence with the core network. Therefore, in the case of inter-system handover, it is generally only necessary to specify the target system format for the UE. If it is inter-RAT handover, the UE adopts the corresponding core network.
  • the non-access stratum (NAS) performs the subsequent process.
  • the target base station to be switched is an eLTE base station
  • the eLTE base station corresponds to the LTE system
  • the core network corresponding to the eLTE base station has two options: EPC and NGC, so when the UE performs the LTE base station to the eLTE
  • the base station or the NR base station from the 5G to the eLTE base station
  • the UE uses the NAS corresponding to the default EPC of the prior art, and the NG-Core that is switched to the eLTE base station connection cannot be completed. Therefore, it is necessary to indicate to the UE the core network type corresponding to the target system during the handover process.
  • the eLTE eNB supports both the EPC and NG-Core core networks. If the eLTE eNB uses the tracking area identifier (TAI) assigned by the EPC, or the eLTE eNB At the same time, the TAI assigned by the EPC and the moving area identifier (MAI) allocated by the NG-Core are configured, or the TAI allocated by the EPC and the MAI allocated by the NG-Core are the same format identifier, and the source MME cannot correctly identify the NG-Core, which cannot complete the core network migration, and thus affects the handover process of the UE. Meanwhile, if eLTE The eNB connects to multiple NG-Cores and cannot determine which NG-Core to switch to based on existing information.
  • TAI tracking area identifier
  • MAI moving area identifier
  • the target base station eLTE eNB supports both the EPC and the NG-Core core network, if The eLTE eNB adopts a tracking area identifier (TAI) allocated by the EPC, or the eLTE eNB simultaneously configures the TAI allocated by the EPC and the moving area identifier (MAI) allocated by the NG-Core, or the EPC allocated.
  • TAI tracking area identifier
  • MAI moving area identifier
  • the source core network device cannot correctly identify whether the target core network is NG-Core, and the cross-system handover involving the core network migration cannot be completed.
  • the handover within the system which in turn affects the handover process of the UE. Therefore, based on the architecture of the New RAT access network (or the next-generation radio access network) and the existing radio access network, the embodiment of the present invention provides a scenario in which the target base station supports both the source core network and the target access network. A switching method.
  • FIG. 2 is a handover method according to an embodiment of the present invention. As shown in FIG. 2, the method includes steps S201-S202:
  • the source base station determines that the user equipment UE is handed over to the target base station.
  • the source base station is connected to the source core network device, and the target base station is respectively connected to the source core network device and the target core network device.
  • the source core network device and the target core network device belong to a core network under different standards.
  • a feasible design includes: in this step S201, the source base station can be connected to at least one core network, which includes the source core network; and the target base station can be connected to at least two core networks, including the source core network.
  • the target core network may be different from the source core network, and the target core network may be the same as the source core network.
  • a communication interface exists between the source base station and the source core network device; and a communication interface exists between the target base station and the source core network device and the target core network device.
  • the source core network may be the same as the target core network, and the source core network may be different from the target core network.
  • the source base station may determine the target base station according to the measurement report reported by the UE, where the measurement report may include signal transmission information such as signal quality and signal strength of each base station measured by the UE, and the source base station may transmit according to signals of each base station.
  • the specific selection process is not described herein.
  • the source base station sends a handover required message to the source core network device, where the handover request message includes identification information of the target core network device.
  • the name of the handover request message is not limited. Functionally, as long as the source base station sends the identification information of the target core network device to the source core network device, the message for requesting the handover may be used. Optionally, the identification information of the target core network device may also be carried in the message to the source core network device, which is not limited herein.
  • the source core network device searches for the target core network device according to the received identification information of the target core network device, and sends a relocation request message (or has a relocation request message) to the target core network device.
  • a relocation request message or has a relocation request message
  • the target core network device performs a response process after receiving the reconfiguration request message.
  • the handover request message may be used to request the target base station to prepare resources in advance.
  • the handover request message may be used to indicate that the source core network device and the target core network device perform a core network migration process.
  • the core network migration process refers to a process of migrating the context of the UE from the source core network to the target core network, and the source core network device searches for the target core network device according to the identification information of the target core network device, and The target core network device sends a relocation request message, and a series of response processes after the target core network device receives the reconfiguration request message.
  • the identification information of the target core network device may include one of identifier information of the target core network, core network connection indication information, and a location area identifier allocated by the target core network device to the target base station. a combination of multiple pieces of information, the connection indication information being used to indicate that the target base station has a connection with the target core network.
  • the target core network device can be the same device as the source core network device.
  • a feasible switching design includes:
  • S203 The target core network device sends a message for the handover request to the target base station.
  • the message for handover may be a handover request message.
  • the message (or handover request message) used for the handover request carries type information of the target core network and/or type information of the source core network.
  • the message (or handover request message) for handover may also be used to request the target base station to prepare resources for handover.
  • the target base station sends a response to the target core network device.
  • the target base station sends a response to the target core network device, where the response may be a handover request ACK message, or
  • the handover request response message carries a handover indication that needs to be sent to the UE, for example, the handover indication is a handover command message, or the handover indication includes a handover command message.
  • the handover indication (or handover command message) may be included in a target to source transparent container.
  • the handover indication (or handover command message) carries the type information of the target core network, and the type information of the target core network is used to indicate that the NAS layer corresponding to the target core network needs to be used after the UE switches to the target base station.
  • the type information of the target core network may be carried by using the foregoing message nesting in S204, as long as the type information of the target core network may be included in the response sent by the target base station to the target core network device.
  • the type information of the target core network may also be carried in other messages sent by the target base station to the target core network device, as long as the type information of the target core network can be transmitted and the UE is instructed to use the target after switching to the target base station.
  • the NAS layer corresponding to the core network can be used.
  • the target core network type information includes at least one of the following: a target core network type, a NAS layer used after the handover, and an indication of whether to replace the currently used NAS layer.
  • the handover command message (or the handover indication) carries the type information of the target core network, and any one of the following expressions may be adopted:
  • Method 1 Contains the core network type information displayed, such as EPC or NGC.
  • Manner 2 Contains implicit indications, such as maintaining the source core network type or replacing the core network type.
  • the indication is performed by a specific message bit. For example, 0 indicates that the target core network type is the same as the source core network type, and 1 indicates that the target core network type is different from the source core network type, and the UE needs to change the working NAS layer. It can be understood that, if the method is adopted, the target base station needs to obtain the source core network type. In this case, the source core network type information needs to be carried in the message sent by the target core network device to the target base station for the handover request.
  • the handover command message (or the handover indication) carries the type information of the target core network, and may adopt any one of the following options:
  • the RRCConnectionReconfiguration message can be used as the handover command (the name of the specific message is not limited, as long as it can be used as the RRC message of the handover command), in the RRCConnectionReconfiguration
  • the information element (IE) of the message carries the type information of the target core network, for example, the IE (for example, MobilityControlInfo) in the RRCConnectionReconfiguration message carries the target cell identifier, and the information indicating that the target core network type is NGC. .
  • the UE switches the EPC NAS to the NGC NAS.
  • the RRC message may further carry security related configuration information of the NGC.
  • EPC of eLTE indicates that the UE accesses the core network device whose core network type is EPC through the eLTE base station.
  • the "NGC of the eLTE” identifies that the UE accesses the core network device whose core network type is NGC through the eLTE base station.
  • the RRCConnectionReconfiguration message can also be used as the handover command (the name of the specific message is not limited, as long as it can be used as the RRC message of the handover command)
  • the type information of the target core network for example, the IE (MobilityControlInfo) in the message carries the target cell identifier, and the information indicating that the target core network type is EPC.
  • the EPC NAS is continued to be used at the target station.
  • the RRCConnectionReconfiguration message carrying the MobilityControlInfo is not used as the handover command, the default target core network is the EPC.
  • the MobilityFromNRCommand message can be used as the handover command for the EPC scenario to be switched from the NR base station to the eLTE.
  • the type information of the target core network is carried.
  • the IE (handover) in the message carries the target RAT type.
  • the UE switches the NGC NAS to the EPC NAS.
  • the message may carry security related configuration information of the EPC.
  • the MobilityFromNRCommand message can be used as the handover command, and the type information of the target core network is carried.
  • the IE (handover) in the message carries the target type (targetRAT type).
  • the UE keeps using the NGC NAS.
  • the RRCConnectionReconfiguration message may be used as the handover command, where the type information of the target core network is carried.
  • the IE MobilityControlInfo
  • the target core network type is NGC information.
  • the UE keeps using the NGC NAS.
  • an unenhanced RRCConnectionReconfiguration message carrying MobilityControlInfo is used as the handover command, the target core network is the same as the source core network, and the UE should not change the NAS layer and keep using the NGC NAS.
  • the RRCConnectionReconfiguration message is used as the handover command, and the type information of the target core network is carried.
  • the IE (MobilityControlInfo) in the message carries the target cell identifier, and carries the target.
  • the core network type is EPC information.
  • the UE switches the NGC NAS to the EPC NAS.
  • the RRC message may further carry security related configuration information of the EPC.
  • the default target core network is the EPC.
  • Manner 2 Define a new RRC message type, which is used to indicate that the source base station and/or the target base station are eLTE handover scenarios. Any of the following examples can be used:
  • the UE switches the EPC NAS to the NGC NAS.
  • the newly defined first RRC message indicates that the target core network type is NGC by using information included in the message or a function definition of the message itself.
  • the message carries security related configuration information of the NGC.
  • the EPC that is switched from the LTE base station or the eLTE EPC to the eLTE uses the original RRCConnectionReconfiguration message as the handover command.
  • the default target core network type is EPC. After receiving the message, the UE does not replace the NAS layer.
  • the EPC that is switched from the NR base station to the eLTE uses the MobilityFromNRCommand message as the handover command.
  • the default target core network type is EPC.
  • the UE switches the NGC NAS to the EPC NAS.
  • the message carries security related configuration information of the EPC.
  • the NGC that is switched from the NR base station to the eLTE uses the second RRC message as the handover command to indicate that the target core network type is NGC.
  • the UE keeps using the NGC NAS.
  • the newly defined second RRC message indicates that the target core network type is NGC by using information carried in the message or a function definition of the message itself.
  • the NGC is switched from the NGC of the eLTE to the NGC of the eLTE.
  • the first new RRC message is used as the handover command to indicate that the target core network type is NGC.
  • the UE keeps using the NGC NAS.
  • the message carries security related configuration information of the NGC.
  • the newly defined first new RRC message indicates that the target core network type is NGC by using information carried in the message or a function definition of the message itself.
  • the existing RRCConnectionReconfiguration message carrying the MobilityControlInfo is used as the handover command,
  • the standard core network is the same as the source core network, and the UE does not change the NAS layer and keeps using the NGC NAS.
  • the UE switches the NGC NAS to the EPC after receiving the message.
  • the message carries the security related configuration information of the EPC.
  • the newly defined third RRC message indicates that the target core network type is NGC by using information carried in the message or a function definition of the message itself.
  • the existing RRCConnectionReconfiguration message carrying MobilityControlInfo is used as the handover command, it indicates that the target core network is an EPC, and the UE switches to the target base station and the EPC NAS.
  • the newly defined first RRC message, the second RRC message, and the third RRC message refer to the currently defined RRC message for the handover command (for example, the RRCConnectionReconfiguration message carrying the MobilityControlInfo in the LTE, the Handoverfrom LTE message, the HandovertoLTE message)
  • Different messages may be represented by different message identifiers, different IEs included in the message, and different actions of the UE after receiving the message and receiving the existing RRC message.
  • the UE interprets the handover command message at the RRC layer, and indicates that the NAS needs to be replaced after the handover, and indicates to the NAS corresponding to the target core network, and optionally, the NAS corresponding to the source core network.
  • the above indication process can be implemented by an inter-layer primitive interaction between the NAS and RRC layers.
  • the target core network device sends a message for reconfiguration response to the source core network device, where the handover indication is carried.
  • the target core network device after receiving the response information sent by the target base station, the target core network device sends a message for the reconfiguration response to the source core network device, where the handover indication is included.
  • the handover indication is used by the source base station to send to the UE through an air interface to indicate that the UE switches to the target base station.
  • the handover indication is a handover command message, or the handover indication includes a handover command message.
  • the handover indication (or handover command message) may be included in a target to source transparent container.
  • the handover indication (or handover command message) carries the type information of the target core network, and the type information of the target core network is used to indicate that the NAS layer corresponding to the target core network needs to be used after the UE switches to the target base station.
  • the source core network sends a message for the handover command to the source base station, where the handover indication is carried.
  • the message for the handover command may be a handover command message.
  • the message (or handover command message) used for the handover command carries a handover indication.
  • the handover indication is used by the source base station to send to the UE through an air interface to indicate that the UE switches to the target base station.
  • the handover indication is a handover command message, or the handover indication includes a handover command message.
  • the handover indication (or handover command message) may be included in a target to source transparent container.
  • the handover indication (or handover command message) carries the type information of the target core network, and the type information of the target core network is used to indicate that the NAS layer corresponding to the target core network needs to be used after the UE switches to the target base station.
  • the source base station sends a handover indication to the UE by using an air interface, where the handover indication carries type information of the target core network, and is used to indicate a core network type that the UE accesses through the target base station.
  • the target core network type information includes at least one of the following: a target core network type, a NAS layer used after the handover, and an indication of whether to replace the currently used NAS layer.
  • the handover indication carries the type information of the target core network, and any one of the following expressions may be adopted:
  • Method 1 Contains the core network type information displayed, such as EPC or NGC.
  • Manner 2 Contains implicit indications, such as maintaining the source core network type or replacing the core network type.
  • the indication is performed by a specific message bit. For example, 0 indicates that the target core network type is the same as the source core network type, and 1 indicates that the target core network type is different from the source core network type, and the UE needs to change the working NAS layer. It can be understood that, if the method is adopted, the target base station needs to obtain the source core network type. In this case, the source core network type information needs to be carried in the message sent by the target core network device to the target base station for the handover request.
  • the switching indication carries the type information of the target core network, and may adopt any of the following optional methods:
  • Method 1 Add the target core in the existing radio resource control (RRC) message type.
  • RRC radio resource control
  • Type information of the heart network such as:
  • the RRCConnectionReconfiguration message can be used as the handover command (the name of the specific message is not limited, as long as it can be used as the RRC message of the handover command), in the RRCConnectionReconfiguration
  • the information element (IE) of the message carries the type information of the target core network, for example, the IE (for example, MobilityControlInfo) in the RRCConnectionReconfiguration message carries the target cell identifier, and the information indicating that the target core network type is NGC. .
  • the UE switches the EPC NAS to the NGC NAS.
  • the RRC message may further carry security related configuration information of the NGC.
  • EPC of eLTE indicates that the UE accesses the core network device whose core network type is EPC through the eLTE base station.
  • the "NGC of the eLTE” identifies that the UE accesses the core network device whose core network type is NGC through the eLTE base station.
  • the RRCConnectionReconfiguration message can also be used as the handover command (the name of the specific message is not limited, as long as it can be used as the RRC message of the handover command)
  • the type information of the target core network for example, the IE (MobilityControlInfo) in the message carries the target cell identifier, and the information indicating that the target core network type is EPC.
  • the UE After receiving the RRC message, the UE continues to use the EPC NAS at the target station.
  • the RRCConnectionReconfiguration message carrying the MobilityControlInfo is not used as the handover command, the default target core network is the EPC.
  • the MobilityFromNRCommand message can be used as the handover command for the EPC scenario to be switched from the NR base station to the eLTE.
  • the type information of the target core network is carried.
  • the IE (handover) in the message carries the target RAT type.
  • the UE switches the NGC NAS to the EPC NAS.
  • the message may carry security related configuration information of the EPC.
  • the MobilityFromNRCommand message can be used as the handover command, and the type information of the target core network is carried.
  • the IE (handover) in the message carries the target type (targetRAT type).
  • the UE keeps using the NGC NAS.
  • the RRCConnectionReconfiguration message may be used as the handover command, where the type information of the target core network is carried.
  • the IE MobilityControlInfo
  • the target core network type is NGC information.
  • the UE keeps using the NGC NAS.
  • an unenhanced RRCConnectionReconfiguration message carrying MobilityControlInfo is used as the handover command, the target core network is the same as the source core network, and the UE should not change the NAS layer and keep using the NGC NAS.
  • the RRCConnectionReconfiguration message is used as the handover command, and the type information of the target core network is carried.
  • the IE (MobilityControlInfo) in the message carries the target cell identifier, and carries the target.
  • the core network type is EPC information.
  • the UE switches the NGC NAS to the EPC NAS.
  • the RRC message may further carry security related configuration information of the EPC.
  • the default target core network is the EPC.
  • Manner 2 Define a new RRC message type, which is used to indicate that the source base station and/or the target base station are eLTE handover scenarios. Any of the following examples can be used:
  • the UE switches the EPC NAS to the NGC NAS.
  • the newly defined first RRC message indicates that the target core network type is NGC by using information included in the message or a function definition of the message itself.
  • the message carries security related configuration information of the NGC.
  • the EPC that is switched from the LTE base station or the eLTE EPC to the eLTE uses the original RRCConnectionReconfiguration message as the handover command.
  • the default target core network type is EPC. After receiving the message, the UE does not replace the NAS layer.
  • the EPC that is switched from the NR base station to the eLTE uses the MobilityFromNRCommand message as the handover command.
  • the default target core network type is EPC.
  • the UE switches the NGC NAS to the EPC NAS.
  • the message carries security related configuration information of the EPC.
  • the NGC that is switched from the NR base station to the eLTE uses the second RRC message as the handover command to indicate that the target core network type is NGC.
  • the UE keeps using the NGC NAS.
  • the newly defined second RRC message indicates that the target core network type is NGC by using information carried in the message or a function definition of the message itself.
  • the NGC is switched from the NGC of the eLTE to the NGC of the eLTE.
  • the first new RRC message is used as the handover command to indicate that the target core network type is NGC.
  • the UE keeps using the NGC NAS.
  • the message carries security related configuration information of the NGC.
  • the newly defined first new RRC message indicates that the target core network type is NGC by using information carried in the message or a function definition of the message itself.
  • the existing RRCConnectionReconfiguration message carrying MobilityControlInfo is used as the handover command, it indicates that the target core network is the same as the source core network, and the UE does not change the NAS layer and keeps using the NGC NAS.
  • the UE switches the NGC NAS to the EPC after receiving the message.
  • the message carries the security related configuration information of the EPC.
  • the newly defined third RRC message indicates that the target core network type is NGC by using information carried in the message or a function definition of the message itself.
  • the existing RRCConnectionReconfiguration message carrying MobilityControlInfo is used as the handover command, it indicates that the target core network is an EPC, and the UE switches to the target base station and the EPC NAS.
  • the newly defined first RRC message, the second RRC message, and the third RRC message refer to the currently defined RRC message for the handover command (for example, the RRCConnectionReconfiguration message carrying the MobilityControlInfo in the LTE, the Handoverfrom LTE message, the HandovertoLTE message)
  • Different messages may be represented by different message identifiers, different IEs included in the message, and different actions of the UE after receiving the message and receiving the existing RRC message.
  • the UE After receiving the handover indication sent by the source base station, the UE uses the NAS layer corresponding to the target core network after switching to the target base station according to the type information of the target core network carried in the UE. For example, if the target core network is the same as the source core network, the NAS corresponding to the source core network is used. If the target core network is different from the source core network, the NAS corresponding to the source core network is stopped, and the target core network is enabled. NAS. Specifically, the UE interprets the handover command message at the RRC layer, and learns that the NAS needs to be replaced after the handover, and indicates to the NAS corresponding to the target core network, and optionally also to the NAS corresponding to the source core network.
  • the above indication process can be implemented by an inter-layer primitive interaction between the NAS and RRC layers.
  • the source base station determines, according to the UE capability information and the acquired configuration information of the target base station, the core network migration process of the source core network device and the target core network device, or determines the type of the target core network. information. .
  • the UE capability information is used to indicate that the UE supports the service of the source base station system and the service of the target base station system, or the UE capability information is used to indicate that the UE supports the target core network service of the target base station standard.
  • the manner in which the source base station obtains the configuration information of the target base station may be any one of the following: obtained by using an interface message between the source base station and the target base station, obtained by using an interface message between the source base station and other neighboring base stations, and configured by the OAM, And the UE reports (for example, measurementResult in ANR).
  • the UE can read the broadcast message of the neighboring base station, and the broadcast message of the neighbor base station carries the type information of the core network, so as to obtain the type information of the core network of the neighbor base station, and the UE reports the type information of the core network to the serving base station. (eg reporting this information via a measurement report).
  • the core network type information may include one or a combination of the following information: identity information of the core network, core network connection indication information, and a location area allocated by the device of the core network to the neighbor base station.
  • the connection indication information is used to indicate that the target base station has a connection with the target core network.
  • the handover request message further includes a handover type indication, where the indication indicates a handover type of the source base station to the target base station, and may further include type information of the source core network and type information of the target core network. .
  • the handover command may carry the type information of the source core network and the type information of the target core network, and is used to indicate that the UE is applied in subsequent handover.
  • the steps or optional designs involved in the method of the embodiment of the present application may select some or all of the process actions according to actual needs, so that the target core network device can be transmitted between any two network elements involved in the method.
  • the type information enables the network elements involved in the handover process to accurately identify the type of the target core network device.
  • the steps may be selected according to the needs of the specific problem to be solved. For example, when the identification information of the target core network device needs to be transmitted in the target base station and the target core network device, only the solution involved in step 204 may be selected. .
  • each network element function involved in the embodiment of the present application may be implemented in a device having a hardware structure, where the hardware structure includes: a memory, a transceiver, and at least one processor, where the memory stores an instruction, where The memory, the transceiver, and the at least one processor are interconnected by a line for performing the foregoing method steps or operations (in whole or in part) of messaging performed by the network element device in each feasible design; the at least one processing The device invokes the instruction stored in the memory to perform the aforementioned method steps or processing operations (in whole or in part) in the network element device in each feasible design.
  • each network element function involved in the embodiment of the present application may be implemented in a chip system having a hardware structure, where the chip system is applicable to the network element involved in the foregoing, the hardware structure includes: at least one processor And a memory circuit that is responsible for the information exchange between the chip system and the outside world, the memory, the interface circuit and the at least one processor being interconnected by a line, wherein the at least one memory stores an instruction; the instruction is by the at least one The processor executes to perform the foregoing method steps or processing operations (in whole or in part) in the network element device in each feasible design.
  • each network element function involved in the embodiment of the present application may be implemented by using a computer instruction, where the instruction may be stored in a computer readable storage medium, when the instruction is run on the computing device, to perform the foregoing method.
  • the processing operations performed by the network element device in steps or in all feasible designs.
  • the source base station after determining that the UE is handed over to the target base station, the source base station sends a handover request message to the source core network device, where the handover request message includes identification information of the target core network device, where the handover request is performed.
  • the message is used to indicate that the source core network device and the target core network device perform a core network migration process.
  • the technical solution provided by the embodiment of the present invention can be applied to the target base station supporting the handover scenario of the source core network and the target core network, and carrying the identification information of the target core network device in the handover request message, so that the source core network device can accurately identify the target.
  • the core network equipment completes the core network migration and improves the switching efficiency.
  • the embodiments of the present invention can refer to each other.
  • the core network to which the LTE eNB is connected is the EPC, and the EPC is the source core network, and the source core network device includes the MME in the EPC (hereinafter referred to as the source MME); the core network to which the eLTE eNB is connected is the EPC and the NG-Core.
  • NG-Core is the target core network, and the target core network equipment includes devices in the NG-Core.
  • the handover method provided by the embodiment of the present invention may be applicable to a scenario in which the UE switches from the source base station to the target base station that supports the source core network and the target core network, and the embodiment of the present invention does not perform any specific system for the source base station and the target base station. limited.
  • FIG. 3 is a schematic diagram of a signaling process of a handover method according to an embodiment of the present invention, including steps S301-S308:
  • the LTE eNB sends an interface setup request message to the eLTE eNB.
  • the interface establishment request message may be an X2 interface request (X2setup request) message, that is, the LTE eNB communicates with the eLTE eNB through the X2 port.
  • X2setup request X2setup request
  • the existing X2 interface is reused between the LTE eNB and the eLTE eNB, and a new interface may be used, which is not limited in the present invention.
  • the interface setup request message includes configuration information of the LTE eNB, where the information about the core network connected by the LTE eNB is specifically, and may be identifier information of the core network, and/or an indication that the LTE eNB is connected to the core network. Letter interest.
  • the interface setup request message may further include information about a primary serving cell or a neighboring cell under the LTE eNB, including a physical cell identifier (PCI), and a global cell identifier (cell global identification, Information such as CGI) is not described here.
  • PCI physical cell identifier
  • CGI global cell identifier
  • the eLTE eNB After receiving the interface setup request information, the eLTE eNB sends an interface setup response message to the LTE eNB, where the interface setup response information message includes configuration information of the eLTE eNB.
  • the interface establishment response message may be an X2 setup response (X2setup response) message.
  • the configuration information of the eLTE eNB includes information of one or more core networks connected to the eLTE eNB, where specifically, the identifier information of the core network, and/or the eLTE eNB is connected to each core network. Connection indication information, etc., is used to inform the LTE eNB of its core network connection.
  • the information of one or more core networks connected by the eLTE eNB may be information of all types of core networks supported by the eLTE eNB, including information of the source core network, or other cores supported by the eLTE eNB except the source core network. Information on the web.
  • the eLTE eNB is connected to the NG-Core and the EPC, and the LTE eNB sends the X2 setup request message to the eLTE eNB.
  • the eLTE eNB may include the connection indication information of the LTE-Core and the identifier of the NG-Core in the X2 setup response message.
  • One or more pieces of information in the information (next-generation Core IDentity, NG-Core ID); optionally, the connection indication information of the ELTE eNB connected to the EPC and/or the identification information of the EPC may also be included.
  • the identifier information of the NG-Core may be the MME ID or the S-GW ID.
  • the eLTE eNB may connect multiple NG-Cores, and the X2setup request message may carry information of each NG-Core.
  • the foregoing configuration information may further include load information of each NG-Core connected by the eLTE eNB, where the load information may be used by the LTE eNB to decide whether to initiate a core network migration process and select a suitable NG-Core for core network migration. .
  • the foregoing load information may also be transmitted to the LTE eNB by using a resource status update message.
  • each base station device can obtain information of the connected core network.
  • the eLTE eNB has two location area identifiers, a TAI allocated by the EPC, or a tracking area code (TAC), and a MAI, TAI allocated by the NG-Core. It can be used in a different format than MAI, or MAI can be in the same format as TAI. Both the MAI and the TAI may be included in the configuration message of the eLTE eNB and sent to the LTE eNB.
  • TAI tracking area code
  • the eLTE eNB may not send the configured TAI to the LTE eNB.
  • the eLTE eNB may also configure the NG-Core related information by using a base station configuration update message.
  • the information is sent to the LTE eNB.
  • the eLTE eNB detects that the configuration information of the eLTE is changed, the LTE eNB may be notified by the message, and the updated configuration information, for example, the updated NG-Core related information, is carried in the message.
  • the two base stations acquire the configuration information of the base station, including the information of the core network supported by the other party. Further, the LTE eNB may decide to perform core network migration according to the acquired configuration information of the eLTE eNB.
  • the core network migration process includes steps S303-S3011:
  • the LTE eNB determines to handover the UE to the eLTE eNB.
  • the LTE eNB may determine the target base station to be handed over by the UE according to the measurement report reported by the UE or the related measurement information of the UE by using the measurement configuration, that is, determine that the eLTE eNB is the target base station.
  • the LTE eNB may further acquire capability information of the UE, where the UE The capability information is used to indicate that the UE supports both the source base station standard service and the target base station standard service.
  • the LTE eNB may determine, according to the UE capability information and the configuration information of the eLTE eNB acquired in the interface establishment process or the base station configuration update process, the NG-Core accessed by the eLTE eNB, that is, the target core network device performs core network migration. process.
  • the LTE eNB may learn that the eLTE eNB is connected to the NG-Core according to the connection indication information in the configuration information of the eLTE eNB, and further determine whether the NG-Core is suitable for handover according to the core network load information; or the LTE eNB may identify the core network according to the core network identifier.
  • the information directly identifies the NG-Core.
  • the LTE eNB sends a handover request message to the source MME, where the handover request message includes the identification information of the target core network, where the handover request message is used to indicate that the source core network device and the target core network device perform core network migration. process.
  • the identification information of the target core network includes one or more pieces of information of a location area identifier of the target eLTE eNB, identification information of the core network, and core network migration indication information.
  • the source MME as the device responsible for signaling processing in the source core network, receives and processes the handover request message sent by the LTE eNB.
  • the configuration information of the eLTE eNB acquired by the LTE eNB includes the MAI, the NG-Core ID allocated by the NG-Core for the eLTE eNB, and the eLTE eNB is connected to the NG-Core.
  • the connection indication information includes any one or more of the MAI, the NG-Core ID, and the connection indication information in the identification information of the eLTE eNB.
  • the foregoing configuration information may further include a TAI allocated by the EPC for the eLTE eNB. Through any one of the above identification information, the source core network device can search for the corresponding target core network device.
  • the eLTE eNB is configured with only the TAI, and the configuration information of the eLTE eNB acquired by the LTE eNB includes the NG-Core ID and the connection indication information, the identifier information of the eLTE eNB includes the NG-Core ID and/or the connection. Instructions.
  • the configuration information may further include a TAI to which the eLTE eNB is allocated.
  • the identification information of the target core network device may be included in an information element (IE) of an existing handover request message, such as a target ID cell, or may be included in a new cell.
  • IE information element
  • the LTE eNB may select the NG-Core suitable for handover, that is, determine the target NG-Core according to the acquired load information of each NG-Core, and input the corresponding core network information. Write to the switch request message.
  • the handover request message may further include handover type information, which is used to indicate that the type of the core network migration is LTE to New RAT.
  • handover type information which is used to indicate that the type of the core network migration is LTE to New RAT.
  • a new type may be added to the existing handover type cell, for example, The LTE to NR", or "LTE to 5G", etc., is not limited in this embodiment of the present invention.
  • the handover request message may further include a core network migration indication information, where the source core network is instructed to perform core network migration.
  • the handover type information may be used as a display core network migration indication; or an indication bit may be independently set, which is not limited.
  • S305 The source MME searches for the target core network device according to the handover request message.
  • the source MME detects the core network reconfiguration request sent by the LTE eNB from the handover request message, and according to the identification information of the target core network device in the handover request message, the target NG-Core can be found and prepared for the NG-Core. Send a forward relocation request message.
  • the target NG-Core may be directly determined according to the NG-Core ID.
  • the source MME may determine the NG-Core corresponding to the MAI by searching the database.
  • the source MME may learn that the target base station is connected to the core network other than the source core network, and further, the source MME may determine that the target MME is a cross-system handover according to the type in the handover type. Then, randomly select a target core network in the core network of the target system. For example, the source MME may determine that the handover of the UE is a handover from the LTE cell to the NEW RAT cell, and the source MME may randomly select one NG-Core.
  • S306 The source MME sends a forward relocation request message to the target NG-Core.
  • the forward weight is The configuration request will be sent to the target MME.
  • the target MME detects the change of the target S-GW, and initiates a create session process to create a bearer resource for the UE in the target S-GW.
  • the NG-Core sends a relocation request message to the eLTE eNB to notify the eLTE eNB to reserve resources.
  • the target MME sends the reconfiguration request message to the eLTE eNB.
  • the eLTE eNB reserves resources for the UE according to the received reconfiguration request message.
  • the relocation request ack message is sent to the NG-Core.
  • the target core network needs to create a forwarding channel in the target core network for the downlink data table from the source core network to the target core network during the handover.
  • the NG-Core has devices such as MME, S-GW, and P-GW
  • the NG-Core needs to be a downlink data packet from the source S-GW to the target S-GW during the handover, at the target S- A data forwarding channel is created in the GW.
  • the target MME sends the forward reconfiguration response to the source MME.
  • the source MME sends a handover command message to the LTE eNB.
  • S3011 The LTE eNB forwards the foregoing sending handover command message to the UE.
  • the UE successfully receiving the foregoing handover command message transmission indicates that the core network migration process is completed.
  • the source base station determines whether to perform core network migration, and obtains related information of the core network connected to the target base station, such as core network identification information and connection indication information, through the interface establishment process or the base station configuration information update process, to determine the target core.
  • the network device thereby accurately completing the handover of the UE from the source base station to the target base station.
  • whether the core network migration is performed may be determined by the target base station.
  • the target base station may be determined by the target base station. The following is still described as an example in which the UE switches from the LTE eNB to the eLTE eNB, and the eLTE eNB supports both the EPC and the NG-Core.
  • FIG. 4 is a schematic diagram of a signaling flow for performing core network migration by an eLTE eNB, including steps S401-S404:
  • S401 The LTE eNB decides to perform base station handover.
  • the source base station may determine, according to the received measurement report of the UE, that the target base station is an eLTE eNB.
  • the LTE eNB sends an interface switching request message to the eLTE eNB.
  • the interface switching request message may be an X2 portover request (X2handover request) message.
  • the interface switching request message includes configuration information of the LTE eNB.
  • the core network migration is determined by the eLTE eNB.
  • the eLTE eNB may determine to perform core network migration according to the UE capability information and the configuration information of the eLTE eNB, where the configuration information of the eLTE eNB includes information of a core network supported by the eLTE eNB, for example, identity information of the core network, eLTE eNB, and At least one core network has connection indication information of the connection, load information of each core network, and the like. If the eLTE eNB supports multiple core networks of the same type, one target core network may be selected according to the load of each core network, or one target core network may be randomly selected.
  • the eLTE eNB may obtain the foregoing UE capability information by using a handover request message sent by the LTE eNB, where the UE capability information is used to indicate that the UE supports both the source base station standard service and the target base station standard service.
  • the eLTE eNB After determining that the core network is migrated, the eLTE eNB sends an interface switch request response message to the LTE eNB.
  • the interface switching request response message is used to instruct the source base station to send the handover request message to the source core network device.
  • the interface switching request response message includes one or more pieces of information, such as a target core network identifier information, a core network migration indication information, and a location area identifier, which are determined by the eLTE eNB to determine a core network migration.
  • the handover request response message may also include configuration information of the eLTE eNB.
  • the LTE eNB may further determine the core network to be migrated.
  • the configuration information of the eLTE eNB refer to other aspects of the present disclosure. The related content of the embodiment is not described herein.
  • the LTE eNB sends the source core network device (shown as the source MME in the figure) according to the received eLTE eNB decision result.
  • a handover request message is sent to instruct the source core network device to initiate a core network migration process to the target core network device (shown as NG-Core in the figure).
  • the LTE eNB may carry the identification information of the target core network in the handover request message sent to the source core network device, that is, the source MME.
  • the identification information of the target core network refer to related content of other embodiments of the present invention. Make a statement.
  • the target base station decides whether to initiate the core network migration process, and then interacts with the configuration information of the base station in the interface switching process, and finally completes the handover process of the UE. Since the target base station can obtain the information of the target core network in time, the accuracy of the decision can be improved, thereby improving the switching efficiency.
  • This embodiment can be applied to a scenario in which an interface between a source base station and a target base station has been established.
  • FIG. 5 is a schematic structural diagram of a base station according to an embodiment of the present invention.
  • the base station can serve as a source base station in the UE handover process, and the base station is connected to the source core network device.
  • the base station includes: a processing unit 501, configured to determine to handover the UE to the target base station, where the target base station is respectively connected to the source core network device and the target core network device.
  • the first sending unit 502 sends a handover request message to the source core network device, where the handover request message includes identification information of the target core network device, where the handover request message is used to indicate the source core network device and the The target core network device performs the core network migration process.
  • the base station further includes a first acquiring unit 503, configured to acquire configuration information of the target base station from the target base station, where the configuration information includes an identifier of a core network device connected to the target base station. Information and/or indication information indicating that the target base station has a connection with the core network device.
  • the base station further includes a second sending unit 504, configured to send an interface switching request message to the target base station, where the interface switching request message includes UE capability information, so that the target base station is configured according to the UE.
  • the capability information and the configuration information of the target base station determine that the source core network device and the target core network device perform a core network migration process, where the UE capability information is used to indicate that the UE supports the source base station standard service and the target at the same time.
  • the first acquiring unit 503 is configured to receive an interface switching request response message from the target base station, where the interface switching request response message includes configuration information of the target base station, and the interface switching request response The message is used to instruct the source base station to send the handover request message to the source core network device.
  • the second sending unit 504 is further configured to: send an interface connection establishment request message to the target base station, where the connection establishment request message includes configuration information of the source base station; the first acquiring unit 503 Specifically, the method is configured to receive an interface connection establishment response message from the target base station, where the connection establishment response message includes configuration information of the target base station.
  • the first obtaining unit 503 is specifically configured to: receive, by the target base station, a base station configuration update message, where the base station configuration update message includes updated configuration information of the target base station.
  • the identification information of the target core network device includes the identifier information and/or the connection indication information of the target core network, where the connection indication information is used to indicate that the target base station and the target core network exist. connection.
  • the configuration information further includes a location area identifier allocated by the core network device connected to the target base station to the target base station.
  • a location area identifier allocated by the core network device connected to the target base station to the target base station.
  • the identification information of the target core network device includes any combination of one or more of the following: identity information of the target core network, connection indication information, and the target core network device is the target. a location area identifier allocated by the base station; wherein the connection indication information is used to indicate that the target base station has a connection with the target core network.
  • the base station further includes a second acquiring unit 505, configured to acquire UE capability information, where the UE capability information is used to indicate that the UE supports the source base station service and the target at the same time.
  • the processing unit 501 is further configured to determine, according to the UE capability information and configuration information of the target base station, a core network migration process between the source core network device and the target core network device. For the process of determining the core network migration by the base station, reference may be made to the related content of some embodiments of the method of the present invention, and details are not described herein.
  • the units in the base station can be connected to each other by means of a communication bus. It is not shown in the figure that the units in the base station can be connected by other connection methods, which is not specifically limited in the embodiment of the present invention.
  • the function of the processing unit 501 may be performed by one processor, and the function of the first sending unit 502 may be performed by a transmitter, and the transmitter may be located at the base station.
  • the communication module can support the base station to communicate with other network devices.
  • the processing unit 502 may be embedded in the hardware of the base station in hardware, or may be stored in the memory of the base station in software, so that the processor invokes the operations corresponding to the foregoing modules.
  • the function of the first obtaining unit 503 may be performed by one receiver; when the base station further includes the second sending unit 504, the second sending unit 504
  • Two first transmission units can be independent of the first transmission unit 502, for example, two independent transmitters, the two transmitters can be located in the communication module of the base station; 502 is an interface between the base station and the core network device.
  • the base station further includes the second obtaining unit 505 the second obtaining unit 505 and the first obtaining unit 503 may be independent hardware devices with receiving functions. For example, two separate receivers, which may be located within the communication module of the base station.
  • the functions of the first obtaining unit 503 and the second sending unit 504 may be implemented by a communication interface between the base station and other base station devices; and the function of the second obtaining unit 505 may be implemented by a transceiver of the base station; Or the function of the first sending unit 502 can be implemented by a communication interface between the base station and a core network device.
  • Fig. 6 is a simplified schematic diagram showing a possible design structure of a base station involved in the above embodiment.
  • the control device can serve as a source base station for UE handover.
  • the base station includes: the processor 601 is configured to control and manage actions of the control device, and perform various functions to support communication services provided by the control device.
  • processor 601 is configured to support a control device to perform the operations performed by the source base station of Figures 2-3, and/or other processes performed by the source base station for the techniques described herein.
  • the memory 602 is configured to store program codes and data for the base station to perform the handover method provided by the embodiment of the present invention, and the program code includes computer operation instructions.
  • the program code stored in the memory 602 can be executed by the processor 601.
  • Transmitter/receiver 604 is used to support base station communication with the UE.
  • the communication module 603 is configured to support communication between the base station and other network entities, such as communication with a core network device or other base station device, and may include a communication interface between the base station and other base stations, and a communication interface between the base station and the core network device.
  • control device may include any number of transmitters, receivers, processors, controllers, memories, communication modules, etc., and details are not described herein.
  • the base station shown in the embodiment of FIG. 5 or FIG. 6 carries the identification information of the target core network device in the handover request message, so that the source core network device can accurately identify the target core network device, thereby completing the core network migration and improving the switching efficiency.
  • the base station provided by the embodiment determines whether to perform the core network migration, acquires the relevant information of the core network connected to the target base station through the interface establishment process or the base station configuration information update process, and determines the target core network device, thereby accurately completing the UE from Switching from the source base station to the target base station.
  • an embodiment of the present invention provides a base station.
  • the base station can serve as a target base station in the UE handover process, and the base station simultaneously connects the target core network and the source core network, wherein the source core network is also connected to the source base station.
  • the base station includes a processing unit 701 for determining a target core network device.
  • the processing unit 701 may select the core network with the lightest load as the target core network according to the load of each core network.
  • the sending unit 702 is configured to send an indication message to the source base station, where the indication message is used by the source core network device and the target core network device to perform a core network migration process.
  • the indication message may be an interface switching request response message, where the interface switching request response message includes configuration information of the target base station.
  • the base station further includes a receiving unit 703, configured to receive an interface switching request message sent by the source base station, where the interface switching request message includes UE capability information, where the UE capability information is used.
  • the processing unit 701 is specifically configured to determine, according to the UE capability information and the configuration information of the target base station, the source core network device and the device, to indicate that the UE supports the service of the source base station system and the service of the target base station system.
  • the target core network device performs a core network migration process; the sending unit 702 is specifically configured to send the interface switch request response message to the source base station.
  • the indication information may be the identifier information of the target core network device determined by the processing unit 701, and the source base station that receives the identifier information of the target core network device may be in the handover request message sent to the source core network device. Carry the identification information of the target core network device.
  • the indication information may also be an independently set indicator bit, which is not limited by the embodiment of the present invention.
  • the units in the base station can be connected to each other by means of a communication bus. It is not shown in the figure that the units in the base station can be connected by other connection methods, which is not specifically limited in the embodiment of the present invention.
  • the functions of the processing unit 701 may be performed by one processor, the function of the transmitting unit 702 may be performed by one transmitter, and the function of the receiving unit 703 may be performed by one receiver.
  • the processing unit 701 may be embedded in or independent of the processor of the base station in hardware, or may be stored in the memory of the base station in software, so that the processor invokes the operations corresponding to the above modules. It can be understood that the actual structural design of the base station can also refer to the base station design shown in FIG. 5, and details are not described herein.
  • the base station provided by the embodiment of the present invention can implement whether the target base station performs the core network migration process and selects the target core network, and the decision accuracy is high, and then the configuration information of the base station is exchanged during the handover process, and the UE handover process is completed efficiently.
  • FIG. 8 is a schematic structural diagram of a core network device according to an embodiment of the present invention.
  • the core network device is respectively connected to the source base station and the target base station, wherein the target base station is also connected to the target core network device, and the UE determines to switch from the source base station to the target base station.
  • the core network device includes: a receiving unit 801, configured to receive a handover request message from a source base station, where the handover request message includes identification information of a target core network device, where the handover request message is used to indicate the source core network device and The target core network device performs a core network migration process.
  • the processing unit 802 is configured to determine the target core network device according to the handover request message.
  • the sending unit 803 is configured to send a forward reconfiguration request message to the target core network device, where the forward reconfiguration request message is used to indicate that the target core network device creates a bearer resource for the UE.
  • the target core network that receives the forward reconfiguration request message sends a relocation request message to the target base station to notify the target base station to reserve resources for the UE.
  • the core network device can perform the steps performed by the source core network device in the embodiment shown in FIG. 2 to FIG. 3.
  • the function modules For specific function descriptions of the function modules, reference may be made to the corresponding method embodiment steps, which are described herein.
  • the function of the receiving unit 801 may be performed by one receiver, the function of the processing unit 802 may be performed by one processor, and the function of the transmitting unit 803 may be performed by one transmitter.
  • the processing unit 802 may be embedded in or independent of the processor of the base station in hardware, or may be stored in the memory of the base station in software, so that the processor invokes the operations corresponding to the above modules.
  • FIG. 9 is a simplified schematic diagram of a possible design structure of a core network device according to an embodiment of the present invention.
  • the core network device may include a transceiver 901, a processor 902, and a memory 903 and a bus 904.
  • the transceiver 901, the processor 902, and the memory 903 are connected by a bus 904. Complete communication with each other.
  • the transceiver 901 can be a communication interface, and the communication interface can be directly or indirectly connected to the corresponding communication interface of the access network device, and used for information interaction between the access network and the core network.
  • the processor 902 can be used to perform the processes involved in the core network device in the method embodiments shown in Figures 2 through 5 and/or other processes used in the techniques described herein.
  • the memory 903 is for storing executable program code or data, the program code including computer operating instructions.
  • the program code stored in the memory 903 can be executed by the processor 902.
  • the specific type of the core network device is not limited in the embodiment of the present invention, and may be an MME or any combination of multiple core network devices.
  • FIG. 10 is a schematic diagram of a communication system according to an embodiment of the present invention.
  • the communication system includes a source base station 1001, a target base station 1002, a source core network device 1003, and a target core network device 1004.
  • the source base station 1001 is connected to the source core network device 1003; the target base station is connected to the source core network device 1003 and the target core network device 1004; respectively, and a communication interface may exist between the source base station 1001 and the target base station 1002.
  • the source base station 1001 may be the base station shown in FIG. 4 or FIG.
  • the target base station 1002 may be the base station shown in FIG. 6, and may perform the steps performed by the target base station or the eLTE eNB in the embodiment shown in FIG. 2 to FIG. I will not repeat them here.
  • the source base station sends a handover request message to the source core network device after determining that the UE is handed over to the target base station, where the handover request message includes identification information of the target core network device, where the handover request is performed.
  • the message is used to indicate that the source core network device and the target core network device perform a core network migration process, where the target base station supports both the source core network and the target core network.
  • Embodiment 1 A handover method includes: determining, by a source base station, a handover of a user equipment UE to a target base station, wherein the source base station is connected to a source core network device, the target base station and the source core network device and a target core network respectively Equipment connected
  • the source base station sends a handover request message to the source core network device, where the handover request message includes identification information of the target core network device, where the handover request message is used to indicate that the source core network device and the target core network device perform core network migration. process.
  • Embodiment 2 The method according to the embodiment 1, further comprising: the source base station acquiring configuration information of the target base station from the target base station, where the configuration information includes identifier information of a core network device connected to the target base station, and / or indication information indicating that the target base station has a connection with the core network device.
  • Embodiment 3 The method according to Embodiment 2, the identification information of the target core network device includes identification information and/or connection indication information of the target core network, where the connection indication information is used to indicate the target base station and the There is a connection in the target core network.
  • Embodiment 4 The method according to Embodiment 2, the configuration information further includes a location area identifier allocated by the core network device connected to the target base station to the target base station.
  • Embodiment 5 The method according to Embodiment 4, wherein the identification information of the target core network device comprises any combination of one or more of the following: identity information of the target core network, connection indication information, and the target core network device. For a location area identifier assigned by the target base station;
  • the connection indication information is used to indicate that the target base station has a connection with the target core network.
  • the source base station acquires UE capability information, where the UE capability information is used to indicate that the UE supports both the source base station system service and the target base station system service; the source base station determines the source according to the UE capability information and the configuration information of the target base station.
  • the core network device and the target core network device perform a core network migration process.
  • Embodiment 7 The method of any of embodiments 1-5, further comprising
  • the source base station sends an interface switching request message to the target base station, where the interface switching request message includes UE capability information, so that the target base station determines the source core network device and the target according to the UE capability information and configuration information of the target base station.
  • the core network device performs a core network migration process, where the UE capability information is used to indicate that the UE supports both the source base station standard service and the target base station standard service; the source base station receives an interface switch request response message from the target base station, and the interface switch request The response message includes configuration information of the target base station, where the interface switch request response message is used to indicate that the source base station sends the handover request message to the source core network device.
  • the acquiring, by the source base station, the configuration information of the target base station from the target base station includes:
  • the source base station sends an interface connection establishment request message to the target base station; the source base station receives an interface connection establishment response message from the target base station, where the connection establishment response message includes configuration information of the target base station.
  • the source base station acquiring configuration information of the target base station from the target base station
  • the source base station receives a base station configuration update message from the target base station, where the base station configuration update message includes updated configuration information of the target base station.
  • Embodiment 10 A base station, comprising: a processing unit, configured to determine to handover a user equipment UE to a target base station, where the source base station is connected to a source core network device, and the target base station and the source core network device and the target respectively
  • the first network sending device is configured to send a handover request message to the source core network device, where the handover request message includes identification information of the target core network device, where the handover request message is used to indicate the source core network device.
  • the core network migration process is performed with the target core network device.
  • the base station further comprising: a first acquiring unit, configured to acquire configuration information of the target base station from the target base station, where the configuration information includes a core network device connected to the target base station The identification information and/or indication information indicating that the target base station has a connection with the core network device.
  • Embodiment 12 The base station according to the embodiment 11, the identification information of the target core network device includes identification information and/or connection indication information of the target core network, where the connection indication information is used to indicate the target base station and the There is a connection in the target core network.
  • Embodiment 13 The base station according to Embodiment 11, the configuration information further includes a location area identifier allocated by the core network device connected to the target base station to the target base station.
  • Embodiment 14 The base station according to Embodiment 13, the identification information of the target core network device includes any combination of one or more of the following: identity information of the target core network, connection indication information, and the target core network device. a location area identifier allocated to the target base station; wherein the connection indication information is used to indicate that the target base station has a connection with the target core network.
  • Embodiment 15 The base station according to any one of embodiments 10-14, further comprising:
  • a second acquiring unit configured to acquire UE capability information, where the UE capability information is used to indicate that the UE supports both the source base station standard service and the target base station standard service; the processing unit is further configured to: the source base station according to the UE capability information And configuring the target base station to determine a core network migration process between the source core network device and the target core network device.
  • a second sending unit configured to send an interface switching request message to the target base station, where the interface switching request message includes UE capability information, so that the target base station determines the source core network according to the UE capability information and configuration information of the target base station.
  • the first acquiring unit is configured to receive an interface switching request response message from the target base station, where the interface switching request response message includes configuration information of the target base station, where The interface switch request response message is used to indicate that the source base station sends the handover request message to the source core network device.
  • Embodiment 17 The base station according to any one of embodiments 10-14, further comprising: a second sending unit, configured to send an interface connection establishment request message to the target base station; the first acquiring unit is specifically configured to use the target The base station receives an interface connection setup response message, where the connection setup response message includes configuration information of the target base station.
  • Embodiment 18 The base station according to any one of embodiments 10-14, wherein the first acquiring unit is configured to receive a base station configuration update message from the target base station, where the base station configuration update message includes an updated configuration of the target base station. information.
  • the processor used in the base station or the core network device in the embodiment of the present invention may be a central processing unit (CPU), a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), and a field programmable gate. Array (FPGA) or other programmable logic device, transistor logic device, hardware component, or any combination thereof. It is possible to implement or carry out the various illustrative logical blocks, modules and circuits described in connection with the present disclosure.
  • the processor may also be a combination of computing functions, for example, including one or more microprocessor combinations, a combination of a DSP and a microprocessor, and the like.
  • the bus according to the embodiment of the present invention may be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus.
  • ISA Industry Standard Architecture
  • PCI Peripheral Component
  • EISA Extended Industry Standard Architecture
  • the bus can be divided into an address bus, a data bus, a control bus, and the like.
  • the bus in the drawings of the present invention is shown by only one thick line, but does not mean that there is only one bus or one type of bus.
  • the steps of a method or algorithm described in connection with the present disclosure may be implemented in a hardware, or may be implemented by a processor executing software instructions.
  • the software instructions may be comprised of corresponding software modules that may be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable hard disk, CD-ROM, or any other form of storage well known in the art.
  • An exemplary storage medium is coupled to the processor to enable the processor to read information from, and write information to, the storage medium.
  • the storage medium can also be an integral part of the processor.
  • the processor and the storage medium can be located in an ASIC. Additionally, the ASIC can be located in the user equipment.
  • the processor and the storage medium may also reside as discrete components in the user equipment.
  • the disclosed systems, devices, and methods may be implemented in other manners without departing from the scope of the present application.
  • the embodiments described above are merely illustrative.
  • the division of the modules or units is only a logical function division.
  • there may be another division manner for example, multiple units or components may be combined. Or it can be integrated into another system, or some features can be ignored or not executed.
  • the units described as separate components may or may not be physically separated, and the components displayed as the unit may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. .
  • Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the embodiment. Those of ordinary skill in the art can understand and implement without any creative effort.
  • the described systems, devices, and methods, and the schematic diagrams of various embodiments may be combined or integrated with other systems, modules, techniques or methods without departing from the scope of the present application.
  • the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in electronic, mechanical or other form.

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Abstract

本发明实施例提供了一种切换方法，包括，源基站在确定将用户设备切换至目标基站后向所述源核心网设备发送切换要求消息，切换要求消息中包括目标核心网设备的识别信息，所述切换要求消息用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程，上述切换方法可以适用于目标基站同时支持源核心网及目标核心网的场景，通过在切换要求消息中携带目标核心网设备的识别信息，使得源核心网设备能够准确识别目标核心网设备，进而完成核心网迁移，提升切换效率。

Description

切换方法、基站及通信系统
本申请要求于2016年8月12日提交中国专利局、申请号为201610666011.2、发明名称为“切换方法、基站及通信系统”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本发明实施例涉及无线通信技术，特别涉及一种切换方法、基站及通信系统。
背景技术
随着用户需求的不断提升，对新无线接入技术(new radio access technology，New RAT or NR or NRAT)的研究越来越深入。相较于现有的无线通信系统，采用新无线接入技术(new radio access technology，New RAT or NR or NRAT)的通信系统能够提供更短的时延，更大的带宽，并且支持大量连接，以满足移动通信日益增长的需求。
在长期演进(Long Term Evolution，LTE)接入网中的基站设备即演进型节点B(evolved NodeB，eNB)的基础上，结合New RAT，产生了演进的LTE基站(evolution of eNB，eLTE eNB)。eLTE eNB为新无线接入网中的基站设备，可以同时连接到现有无线接入网对应的核心网，例如演进型分组核心网(evolved packet core，EPC)，以及新无线接入网对应的核心网，例如下一代核心网(next generation Core，NG-Core)
对于同时支持现有无线接入网业务及New RAT业务的用户设备(user equipment，UE)而言，如果UE在移动过程中欲将接入的基站设备切换(hand over)到eLTE eNB，则需要完成核心网迁移(core network relocation,CN relocation)，例如从EPC切换到NG-Core。
现有技术中，进行异制式(inter-RAT)切换时，源核心网通过目标核心网的跟踪区标识来识别目标核心网，从而完成切换。但从现有无线接入网对应的核心网切换到新无线接入网对应的核心网的过程中，源核心网无法根据上述跟踪区标识准确地找到目标核心网，进而无法完成核心网迁移过程。
发明内容
本发明实施例提供了一种切换方法，基站及通信系统，能够使源核心网准确定位目标核心网。
第一方面，本发明实施例提供了一种切换方法，包括，源基站确定将用户设备(user equipment，UE)切换至目标基站，其中，所述源基站与源核心网设备相连接，所述目标基站分别与所述源核心网设备以及目标核心网设备相连接；随后，所述源基站向所述源核心网设备发送切换要求消息，所述切换要求消息中包括目标核心网设备的识别信息，所述切换要求消息用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程。
本发明实施例提供的切换方法可以适用于目标基站同时支持源核心网及目标核心网的切换场景，通过在切换要求消息中携带目标核心网设备的识别信息，使得源核心网设备能够准确识别目标核心网设备，进而完成核心网迁移，提升切换效率。
在第一方面的一种可能的实现方式中，所述方法还包括，所述源基站从所述目标基站获取所述目标基站的配置信息，所述配置信息中包括与所述目标基站相连接的核心网设备的标识信息和/或指示所述目标基站与该核心网设备存在连接的指示信息。对应地，所述目标核心网设备的识别信息包括所述目标核心网的标识信息和/或连接指示信息，其中，所述连接指示信息用于指示所述目标基站与所述目标核心网存在连接。
在第一方面的一种可能的实现方式中，所述配置信息中包括：与所述目标基站相连接 的核心网设备的标识信息和指示所述目标基站与该核心网设备存在连接的指示信息中的任意一个，以及与所述目标基站相连接的核心网设备为所述目标基站分配的位置区域标识。对应地，所述目标核心网设备的识别信息包括如下任意一个或多个信息的组合：所述目标核心网的标识信息，连接指示信息，以及所述目标核心网设备为所述目标基站分配的位置区域标识；其中，所述连接指示信息用于指示所述目标基站与所述目标核心网存在连接。
在第一方面的一种可能的实现方式中，所述源基站从所述目标基站获取所述目标基站的配置信息包括，所述源基站向所述目标基站发送接口连接建立请求消息；所述源基站从所述目标基站接收接口连接建立响应消息，所述连接建立响应消息中包括所述目标基站的配置信息。
可选地，所述接口建立请求消息中包括所述源基站的配置信息。
在第一方面的一种可能的实现方式中，所述方法还包括，所述源基站获取UE能力信息；所述源基站可以根据所述UE能力信息以及所述目标基站的配置信息，确定所述源核心网设备与所述目标核心网设备进行核心网迁移过程。
可选地，源基站可以向源核心网设备发送核心网迁移指示消息，用于指示源核心网设备发起核心网迁移过程，包括定位目标核心网设备以及向目标核心网设备发送前向重向重配置消息。
采用上述实施方式，在源基站及目标基站的初始连接建立过程中，双方基站完成了配置信息的交互，进而，由源基站快速确定源核心网设备与目标核心网设备进行核心网迁移，整体切换流程简单、高效。
在第一方面的一种可能的实现方式中，所述方法还包括，所述源基站向所述目标基站发送接口切换请求消息，所述接口切换请求消息中包括UE能力信息，以使得所述目标基站根据所述UE能力信息以及所述目标基站的配置信息确定所述源核心网设备与所述目标核心网设备进行核心网迁移过程；所述源基站从所述目标基站接收接口切换请求响应消息，所述接口切换请求响应消息中包含所述目标基站的配置信息，所述接口切换请求响应消息用于指示所述源基站向所述源核心网设备发送所述切换要求消息。
其中，UE能力信息用于指示所述UE同时支持源基站制式的业务以及目标基站制式的业务。
采用上述实施方式，由目标基站决策是否进行核心网迁移过程，进而在切换过程中交互基站的配置信息，并完成UE的切换过程。由于目标基站可以及时获取目标核心网的信息，决策准确性高。
在第一方面的一种可能的实现方式中，所述源基站从所述目标基站获取所述目标基站的配置信息包括，所述源基站从所述目标基站接收基站配置更新消息，所述基站配置更新消息中包括更新的所述目标基站的配置信息。
第二方面，为了实现上述第一方面的切换方法，本发明实施例提供了一种基站，该基站具有实现上述切换方法中源基站行为的功能。所述功能可以通过硬件实现，也可以通过硬件执行相应的软件实现。所述硬件或软件包括一个或多个与上述功能相对应的模块。
在第二方面的一种可能的实现方式中，该基站包括多个功能模块，用于实现上述第一方面中的任一种切换方法，使得源核心网设备能够准确识别目标核心网设备，进而完成核心网迁移，提升切换效率。
在第二方面的一种可能的实现方式中，该基站的结构中包括处理器、收发器以及通信模块，所述处理器被配置为支持基站执行上述切换方法中相应的功能。所述收发器用于支持基站与UE之前的通信，通信模块用于支持基站与其他网络设备之间的通信，向网络设备发送上述切换方法中所涉及的信息或者指令。基站中还可以包括存储器，所述存储器用于与处理器耦合，其保存基站执行上述切换方法必要的程序指令和数据。
第三方面，本发明实施例提供了一种切换方法，包括，目标基站确定目标核心网设备；所述目标基站向源基站发送指示消息，所述指示消息用于所述源核心网设备与所述目标核 心网设备进行核心网迁移过程，其中，所述源基站与源核心网设备相连接，所述目标基站分别与所述源核心网设备以及目标核心网设备相连接。
可选地，上述指示信息可以是接口切换请求响应消息或者所述目标核心网的标识信息护着独立的指示位。
第四方面，为了实现上述第一方面或第三方面的切换方法，本发明实施例提供了一种基站，该基站具有实现上述切换方法中目标基站行为的功能。所述功能可以通过硬件实现，也可以通过硬件执行相应的软件实现。所述硬件或软件包括一个或多个与上述功能相对应的模块。
第五方面，本发明实施例提供了一种切换方法，包括，源核心网设备从源基站接收切换要求消息，所述切换要求消息中包括目标核心网设备的识别信息；所述源核心网设备根据所述切换要求消息，与所述目标核心网设备进行核心网迁移过程。
在第五方面的一种可能的实现方式中，所述源核心网设备根据所述切换要求消息，与所述目标核心网设备进行核心网迁移过程包括，源核心网设备根据所述目标核心网设备的识别信息，搜索到所述目标核心网设备；随后，源核心网设备向目标核心网设备发送前向重配置请求消息，，指示目标核心网设备为UE创建承载资源。
第六方面，为了实现上述第五方面的切换方法，本发明实施例提供了一种核心网设备，该核心网设备具有实现上述切换方法中源核心网设备行为的功能。所述功能可以通过硬件实现，也可以通过硬件执行相应的软件实现。所述硬件或软件包括一个或多个与上述功能相对应的模块。
第七方面，本发明实施例提供了一种通信系统，该系统包括上述第二方面所述的基站即源基站、目标基站、第六方面所述的核心网设备即源核心网设备，其中源基站与源核心网设备相连接，目标基站与源核心网设备相连接，该系统中还包括与目标基站相连接的另一个核心网设备，即目标核心网设备。
可选地，该通信系统中的目标基站可以是第四方面所述的基站，也可以是其他基站。
第八方面，本发明实施例提供了一种计算机存储介质，用于储存为上述第二方面提供的基站所用的计算机软件指令，其包含用于执行上述第一方面所设计的程序。
第九方面，本发明实施例提供了一种计算机存储介质，用于储存为上述第二方面提供的基站所用的计算机软件指令，其包含用于执行上述第三方面所设计的程序。
采用本发明实施例提供的技术方案，源基站在确定将UE切换至目标基站后向所述源核心网设备发送切换要求消息，切换要求消息中包括目标核心网设备的识别信息，所述切换要求消息用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程。本发明实施例提供的技术方案可以适用于目标基站同时支持源核心网及目标核心网的切换场景，通过在切换要求消息中携带目标核心网设备的识别信息，使得源核心网设备能够准确识别目标核心网设备。
附图说明
为了更清楚地说明本发明实施例中的技术方案，下面将对实施例描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1是本发明实施例的一种应用场景示意图；
图2是本发明实施例提供的一种切换方法的流程示意图；
图3是本发明实施例提供的一种切换方法的信令流程示意图；
图4是本发明实施例提供的一种确定核心网迁移的方法信令流程示意图；
图5是本发明实施例提供的一种基站的结构示意图；
图6是本发明实施例提供的一种基站的结构设计示意图；
图7是本发明实施例提供的另一种基站的结构示意图；
图8是本发明实施例提供的一种核心网设备的结构示意图；
图9是本发明实施例提供的一种核心网设备的结构设计示意图
图10是本发明实施例提供的一种通信系统的示意图。
具体实施方式
本发明实施例中描述的技术可用于各种通信系统，例如全球移动通信系统(Global System for Mobile communications，GSM)等2G系统，宽带码分多址(WIDeband Code Division Multiple Access Wireless，WCDMA)系统等3G系统，LTE系统等4G系统，采用新无线接入技术(New RAT)的通信系统等5G(the fifth generation)系统，以及无线局域网(WLAN，wireless local area network)与蜂窝网络融合的通信网络等。其中，采用New RAT的通信系统包括演进的LTE系统，或其他采用5G通信技术的通信系统等，对此不做限定。
本发明实施例中所述的演进型分组核心网(evolved packet core，EPC)是LTE系统的核心网，包括负责信令处理的移动管理实体(mobility management entity，MME)，以及负责数据处理的服务网关(serving gateway，S-GW)，分组数据网关(PDN gateway，P-GW)等设备。
本发明实施例中所述的NG-Core(以下简称NGC)也可以称为新型核心网(New Core)、或者5G New Core、或者5G Core等，是指采用NEW RAT的无线接入网(以下简称“NEW RAT接入网”)连接的核心网。对于类似前述NEW RAT接入网的新一代无线接入网(next generation radio access network，NG RAN)，NG RAN可以包含至少两种类型的基站，一种为采用下一代接入技术(以下简称“New Radio，NR”)的基站(以下简称gNB)，一种为基于原有LTE eNB增强的eLTE eNB。NG-Core独立于现有的核心网而设置。NG-Core中的具体设备可以参照EPC中的设备，例如包含功能类似MME及S-GW的设备，也可以将所有功能实体集成在一个设备中，也可以按功能设备多个设备且每个设备具备一项或多项核心网功能，本发明实施例对此不做特别限定。
本发明实施例所涉及到的UE可以包括具有无线通信功能的手持设备、车载设备、可穿戴设备、计算设备或连接到无线调制解调器的其它处理设备，以及各种形式的用户设备，移动台(mobile station，MS)，终端(terminal)，终端设备(terminal equipment)等等，为方便描述，本申请中，称为“用户设备”或“UE”。
本发明实施例定义基站到UE的单向通信链路为下行链路，而UE到基站的单向通信链路为上行链路。
本发明实施例中所述的资源即为传输资源，包括时域资源以及频域资源，可以用于在上行通信过程或者下行通信过程中承载数据或信令。即本发明实施例中所述的资源可以是基站为UE分配的上行资源，用于UE发送上行数据；也可以是基站为UE分配的下行资源，用于UE接收下行数据。
应理解，本文中术语“和/或”，仅仅是一种描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。另外，本文中字符“/”，表示前后关联对象是一种“或”的关系。
本发明实施例中出现的“多个”是指两个或两个以上。本发明实施例中出现的第一、第二等描述，仅作示意与区分描述对象之用，没有次序之分，也不表示本发明实施例中对设备个数的特别限定，不能构成对本发明实施例的任何限制。
本发明实施例中出现的“连接”是指直接连接或者间接连接等各种连接方式，例如通过通信接口连接不同设备，不做任何限定。
本发明实施例中出现的“网络”与“系统”表达的是同一概念，通信系统即为通信网络。
图1是本发明实施例的一种应用场景示意图。如图1所示的通信系统中，包括LTE接入网中的基站设备(下文及图中表示为LTE eNB)，NEW RAT接入网中的基站设备(下文及图中表示为eLTE eNB)，其中，LTE eNB通过S1接口与EPC相连接，eLTE eNB通过S1接口连接EPC，并通过NG1接口连接NG-Core，且LTE eNB与eLTE eNB之间可以存在通信接口，例如图中所示X2接口，用于交互基站间信息。可以理解，eLTE eNB是在eNB基础上演进的基站设备，支持同时连接不同类型的核心网。可以理解，S1接口或者NG1接口均为示意，实际应用中，eLTE eNB还可以采用其他方式与EPC或者NG-Core连接。
UE在移动过程中会切换接入的基站，以获取最佳的通信服务。如图1所示，当接入LTE eNB的UE移动到eLTE eNB的信号覆盖范围内，UE可以启动切换流程，由LTE eNB切换至eLTE eNB。在此过程中，需要完成核心网迁移(CN relocation)过程，或称为核心网重配置过程，将UE的上下文从EPC切换至NG-Core。
本发明实施例中所述的源基站是指UE当前接入或驻留的基站设备，且UE将从该基站设备切换至其他基站设备，所述源基站可以是GSM中的基站收发台(Base Transceiver Station，BTS)或基站控制器(base station controller)，也可以是WCDMA系统中的节点B(NodeB)或无线网络控制器(radio network controller，RNC)，可以是LTE系统中的演进型节点B(eNB或e-NodeB，evolved Node B)，还可以是5G系统中的NR基站(gNB)或者eLTE eNB，以及还可以是未来演进无线通信网络中或新型无线通信网络中的新型基站。对应地，本发明实施例中所述的目标基站是指UE将切换到的基站设备，所述目标基站可以是eLTE eNB等支持两种以上核心网的基站设备。
本发明实施例中所述的源核心网设备是指为源基站提供核心网服务的设备；本发明实施例中所述的目标核心网设备是指为目标基站提供核心网服务的设备。可以理解，无论源核心网设备还是目标核心网设备都可以包括一个或多个独立设置或集成的功能实体。
一般地，UE在不同制式的无线接入网中切换时，可以由源核心网分配的位置区域标识，识别目标基站所属的核心网，进而确定目标核心网。但是，如果目标基站同时支持源核心网及目标核心网，则目标基站的位置区域标识可能是源核心网分配的，或者同时由源核心网及目标核心网分配了不同格式的位置区域标识，即源核心网和目标核心网属于不同制式下的核心网，不同制式下的核心网分配和维护各自的位置区域标识，或者，源核心网与目标核心网可以为目标基站分配相同格式的位置区域标识，在以上任意一种情况中，源核心网将无法根据位置区域标识准确识别目标核心网。其中，本发明实施例中所述的位置区域标识用于指示空闲态的UE所处的位置区域，所述位置区域由一个或多个小区(cell)构成，包括LTE系统中的跟踪区域(Tracking Area，TA)，UMTS系统中位置区域(Locating Area，LA)，New RAT接入网中的移动区域(Moving Area，MA)等。
制式(也称RAT)通常与核心网是一一对应的，因此在跨系统切换时一般只需要对UE指明目标系统的制式即可，若为inter-RAT切换，则UE采用与目标核心网对应的非接入层(non-access stratum，NAS)进行后续流程。在本申请涉及的场景中，如果切换的目标基站为eLTE基站，eLTE基站对应的制式为LTE，但eLTE基站对应的核心网有两种选择：EPC和NGC，因此当UE进行从LTE基站到eLTE基站(或从5G的NR基站到eLTE基站)的切换时，如不对UE特别指明，则UE会使用现有技术默认的EPC对应的NAS，导致无法完成切换到eLTE基站连接的NG-Core。因此，需要在切换过程中对UE指明目标系统对应的核心网类型。
例如，基于图1所示的应用场景，eLTE eNB同时支持EPC及NG-Core两种制式的核心网，如果eLTE eNB采用的是EPC分配的跟踪区标识(tracking area identifier，TAI)，或者eLTE eNB同时配置了EPC分配的TAI以及NG-Core分配的移动区标识(moving area identifier，MAI)，或者EPC分配的TAI以及NG-Core分配的MAI是同一种格式的标识，源MME无法正确的识别到NG-Core，从而不能完成核心网迁移，进而影响UE的切换过程。同时，如果eLTE  eNB连接多个NG-Core，根据现有信息也无法确定要切换到哪个NG-Core。
再例如，对于从NR中gNB向eLTE eNB切换的场景，和/或，对于从eLTE eNB向eLTE eNB切换的场景，由于目标基站eLTE eNB同时支持EPC及NG-Core两种制式的核心网，如果eLTE eNB采用的是EPC分配的跟踪区标识(tracking area identifier，TAI)，或者eLTE eNB同时配置了EPC分配的TAI以及NG-Core分配的移动区标识(moving area identifier，MAI)，或者EPC分配的TAI以及NG-Core分配的MAI是同一种格式的标识，对于这几种情况，源核心网设备均无法正确识别目标核心网是否为NG-Core，导致不能完成涉及核心网迁移的跨系统切换或系统内的切换，进而影响UE的切换过程。因此，基于New RAT接入网(或下一代无线接入网)和现有无线接入网融合的架构下，针对目标基站同时支持源核心网及目标接入网的情形，本发明实施例提出了一种切换方法。
图2是本发明实施例提供的一种切换方法，如图2所示，该方法包括步骤S201-S202：
S201：源基站确定用户设备UE切换至目标基站。
其中，源基站与源核心网设备相连接，目标基站分别与所述源核心网设备以及目标核心网设备相连接。源核心网设备和目标核心网设备属于不同的制式下的核心网。
一个可行的设计包括：在该步骤S201中，源基站可以与至少一个核心网相连，其中包含源核心网；目标基站可以与至少两个核心网相连，其中包含源核心网。目标核心网可以与源核心网不同，目标核心网也可以与源核心网相同。
具体地，源基站与源核心网设备之间存在通信接口；目标基站与源核心网设备及目标核心网设备之间分别存在通信接口。其中，源核心网可以与目标核心网相同，源核心网也可以和目标核心网不同。
可选地，源基站可以根据UE上报的测量报告确定目标基站，所述测量报告中可以包括UE测量的各基站的信号质量、信号强度等信号传输信息，则源基站可以根据各基站的信号传输情况，确定UE接入的目标基站，具体选择过程在此不做赘述。
S202：所述源基站向所述源核心网设备发送切换要求(handover required)消息，所述切换要求消息中包括目标核心网设备的识别信息。
此处发送切换要求消息的名称不作限定，从功能上说，只要是所述源基站向所述源核心网设备发送的包含该目标核心网设备的识别信息的用于请求切换的消息都可。可选的，该目标核心网设备的识别信息也可以携带在他消息中发给所述源核心网设备，此处也不做限定。
在S202中，源核心网设备根据接收到的该目标核心网设备的识别信息，查找到目标核心网设备，向该目标核心网设备发送重配置请求(relocation request)消息(或者是具有和重配置请求消息功能类似的其他消息，名称不做限定)。目标核心网设备收到该重配置请求消息后执行响应过程。所述切换要求消息可以用于请求目标基站提前准备资源。
或者，
所述切换要求消息可以用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程。具体的，核心网迁移过程是指将UE的上下文从源核心网迁移到目标核心网的过程，包括源核心网设备根据上述目标核心网设备的识别信息，查找到目标核心网设备，并向该目标核心网设备发送重配置请求(relocation request)消息，以及目标核心网设备收到重配置请求消息后的一系列响应过程。
其中，所述目标核心网设备的识别信息可以包括所述目标核心网的标识信息，核心网连接指示信息，以及所述目标核心网设备为所述目标基站分配的位置区域标识中的一种或多种信息的组合，所述连接指示信息用于指示所述目标基站与所述目标核心网存在连接。
一种可行的设计中，目标核心网设备可以与该源核心网设备为同一设备。
与前述操作S201和/或S202相结合，或者，作为单独的方案设计，一种可行的切换设计方案，包括：
S203：目标核心网设备向目标基站发送用于切换请求的消息。
该用于切换的消息可以是切换请求(handover request)消息。一种可行的设计中，所述用于切换请求的消息(或切换请求消息)中携带目标核心网的类型信息和/或源核心网的类型信息。可选的，所述用于切换的消息(或切换请求消息)还可用于请求目标基站为切换准备资源。
S204：目标基站向目标核心网设备发送响应。
具体的，目标基站决定接纳该切换后(目标基站决定的过程为可选)，该目标基站向目标核心网设备发送响应，该响应可以是切换请求响应(handover request ACK)消息，该响应(或切换请求响应消息)中携带需要发给UE的切换指示，比如该切换指示是切换命令(handover command)消息，或者，该切换指示包含切换命令(handover command)消息。一种可行的设计中，该切换指示(或切换命令消息)可以包含在从目标给源的透明容器(target to source transparent container)中传递。所述切换指示(或切换命令消息)携带该目标核心网的类型信息，该目标核心网的类型信息可用于表示UE切换到目标基站后需要使用与该目标核心网对应的NAS层。
可选的，可不必使用S204中前述的消息嵌套来携带该目标核心网的类型信息，只要该目标核心网的类型信息可以包含在目标基站向目标核心网设备发送的响应中即可。可选的，该目标核心网的类型信息还可以携带在目标基站向目标核心网设备发送的其他消息中，只要该目标核心网的类型信息能够得到传递并指示UE切换到目标基站后使用与目标核心网对应的NAS层即可。
所述目标核心网类型信息包含如下至少一种信息：目标核心网类型，切换后使用的NAS层，以及，是否更换当前使用的NAS层的指示。
可选的，所述切换命令消息(或切换指示)携带目标核心网的类型信息，可以采用以下任一种表达方式：
方式一：包含显示的核心网类型信息，例如EPC或者NGC。
方式二：包含隐式的指示，例如保持源核心网类型，或者更换核心网类型。示例性地，用一个特定的消息比特位来进行指示，例如0表示目标核心网类型与源核心网类型相同，1表示目标核心网类型与源核心网类型不同，UE需要改变工作的NAS层。可以理解的，若采用该方式，则需要目标基站获取源核心网类型，此时需要在目标核心网设备向目标基站发送的用于切换请求的消息中携带源核心网类型信息。
可选的，所述切换命令消息(或切换指示)携带目标核心网的类型信息，可以采用以下任一可选的方式：
方式一：在现有无线资源控制(radio resource control，RRC)消息类型中，增加目标核心网的类型信息，比如：
1、对于从LTE基站或eLTE的EPC切换到eLTE的NGC的场景，可以使用RRCConnectionReconfiguration消息作为切换命令(具体消息的名称不做限定，只要是可以用作切换命令的RRC消息即可)，在RRCConnectionReconfiguration消息中的信元(information element，IE)中携带该目标核心网的类型信息，例如，在该RRCConnectionReconfiguration消息中的IE(例如MobilityControlInfo)中携带目标小区标识，以及表示目标核心网类型为NGC的信息。UE收到该RRC消息后，将EPC NAS切换为NGC NAS。可选地，该RRC消息中还可以携带NGC的安全相关的配置信息。需说明的是，所述“eLTE的EPC”表示UE通过该eLTE基站接入核心网类型为EPC的核心网设备。所述“eLTE的NGC”标识UE通过该eLTE基站接入核心网类型为NGC的核心网设备。
2、对于从LTE基站或eLTE的EPC切换到eLTE的EPC的场景，类似的，也可以使用RRCConnectionReconfiguration消息作为切换命令(具体消息的名称不做限定，只要是可以用作切换命令的RRC消息即可)，其中携带目标核心网的类型信息，例如，该消息中的IE(MobilityControlInfo)中携带目标小区标识，以及表示目标核心网类型为EPC的信息。UE 收到该RRC消息后，在目标站继续使用EPC NAS。可选的，如果采用未增强的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则默认目标核心网为EPC。
3、对于从NR基站切换到eLTE的EPC场景，可以使用MobilityFromNRCommand消息作为切换命令，其中携带目标核心网的类型信息，例如，该消息中的IE(handover)中携带表示目标制式类型(target RATtype)为eLTE EPC(eutra-epc)的信息，和/或，在给出目标cell标识时携带表示目标核心网类型为EPC的信息。UE收到该消息后，将NGC NAS切换为EPC NAS。可选地，该消息中可以携带EPC的安全相关配置信息。
4、对于从NR基站切换到eLTE的NGC场景，可以使用MobilityFromNRCommand消息作为切换命令，其中携带目标核心网的类型信息，例如，该消息中的IE(handover)中携带表示目标制式类型(targetRAT type)为eLTE NGC(eutra-ngc)的信息，和/或，在给出目标cell标识时携带表示目标核心网类型为NGC的信息。UE收到该消息后，保持使用NGC NAS。
5、对于从eLTE的NGC切换到eLTE的NGC的场景，可以使用RRCConnectionReconfiguration消息作为切换命令，其中携带目标核心网的类型信息，例如，该消息中的IE(MobilityControlInfo)中携带目标小区标识，携带表示目标核心网类型为NGC的信息，UE收到该消息后，保持使用NGC NAS。可选的，如果采用未增强的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则目标核心网与源核心网相同，UE不该变NAS层，保持使用NGC NAS。
6、对于从eLTE的NGC切换到eLTE的EPC的场景，使用RRCConnectionReconfiguration消息作为切换命令，其中携带目标核心网的类型信息，例如，该消息中的IE(MobilityControlInfo)中携带目标小区标识，携带表示目标核心网类型为EPC的信息，UE收到该消息后，将NGC NAS切换为EPC NAS。可选地，该RRC消息中还可以携带EPC的安全相关配置信息。可选的，如果采用未增强的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则默认目标核心网为EPC。
方式二：定义新的RRC消息类型，用于指示源基站和/或目标基站为eLTE的切换场景。可采用如下任一种示例：
1、从LTE基站或eLTE的EPC切换到eLTE的NGC，使用第一RRC消息作为切换命令，用于指示目标核心网类型为NGC，UE收到该消息后，将EPC NAS切换为NGC NAS。可选的，该新定义的第一RRC消息通过其消息中自带的信息，或者对该消息本身的功能定义，来指示目标核心网类型为NGC。可选地，该消息中携带NGC的安全相关配置信息。
2、从LTE基站或eLTE的EPC切换到eLTE的EPC，使用原有的RRCConnectionReconfiguration消息作为切换命令，默认目标核心网类型为EPC，UE收到该消息后，不更换NAS层。
3、从NR基站切换到eLTE的EPC，使用MobilityFromNRCommand消息作为切换命令，默认目标核心网类型为EPC，UE收到该消息后，将NGC NAS切换为EPC NAS。可选地，该消息中携带EPC的安全相关配置信息。
4、从NR基站切换到eLTE的NGC，使用第二RRC消息作为切换命令，用于指示目标核心网类型为NGC，UE收到该消息后，保持使用NGC NAS。可选的，该新定义的第二RRC消息通过其消息中携带的信息，或者对该消息本身的功能定义，来指示目标核心网类型为NGC。
5、从eLTE的NGC切换到eLTE的NGC，使用第一新RRC消息作为切换命令，用于指示目标核心网类型为NGC，UE收到该消息后，保持使用NGC NAS。进一步可选地，该消息中携带NGC的安全相关配置信息。可选的，该新定义的第一新RRC消息通过其消息中携带的信息，或者对该消息本身的功能定义，来指示目标核心网类型为NGC。可选的，如果现有的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则表示目 标核心网与源核心网相同，UE不改变NAS层，保持使用NGC NAS。
6、从eLTE的NGC切换到eLTE的EPC，使用第三RRC消息作为切换命令，用于指示目标核心网为EPC，UE收到该消息后，UE收到该消息后，将NGC NAS切换为EPC NAS。进一步可选地，该消息中携带EPC的安全相关配置信息。可选的，该新定义的第三RRC消息通过其消息中携带的信息，或者对该消息本身的功能定义，来指示目标核心网类型为NGC。可选的，如果采用现有的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则表示目标核心网为EPC，UE切换至目标基站后EPC NAS。
可理解的，上述新定义的第一RRC消息、第二RRC消息、第三RRC消息是指与当前定义的用于切换命令的RRC消息(例如LTE中携带MobilityControlInfo的RRCConnectionReconfiguration消息、HandoverfromLTE消息、HandovertoLTE消息)不同的消息，不同具体可以表示为消息标识不同、消息中包含的IE不同、UE收到该消息后与收到现有RRC消息的动作不同等。
可选的，所述UE在RRC层解读切换命令消息，得知切换后需要更换NAS，则指示给目标核心网对应的NAS，可选地，也指示给源核心网对应的NAS。示例性地，上述指示过程可以通过NAS和RRC层之间的层间原语交互实现。S205：目标核心网设备向源核心网设备发送用于重配置响应的消息，其中携带切换指示。
具体的，目标核心网设备基于收到目标基站向其发送的响应信息后，向源核心网设备发送用于重配置响应的消息，其中包含切换指示。所述切换指示用于源基站通过空口发送给UE，以指示所述UE切换到目标基站。比如该切换指示是切换命令(handover command)消息，或者，该切换指示包含切换命令(handover command)消息。一种可行的设计中，该切换指示(或切换命令消息)可以包含在从目标给源的透明容器(target to source transparent container)中传递。所述切换指示(或切换命令消息)携带该目标核心网的类型信息，该目标核心网的类型信息可用于表示UE切换到目标基站后需要使用与该目标核心网对应的NAS层。
S206：源核心网向源基站发送用于切换命令的消息，其中携带切换指示。
该用于切换命令的消息可以是切换命令(handover command)消息。一种可行的设计中，所述用于切换命令的消息(或切换命令消息)中携带切换指示。所述切换指示用于源基站通过空口发送给UE，以指示所述UE切换到目标基站。比如该切换指示是切换命令(handover command)消息，或者，该切换指示包含切换命令(handover command)消息。一种可行的设计中，该切换指示(或切换命令消息)可以包含在从目标给源的透明容器(target to source transparent container)中传递。所述切换指示(或切换命令消息)携带该目标核心网的类型信息，该目标核心网的类型信息可用于表示UE切换到目标基站后需要使用与该目标核心网对应的NAS层。
S207：源基站通过空口向UE发送切换指示，所述切换指示携带目标核心网的类型信息，用于指示UE通过目标基站接入的核心网类型。
所述目标核心网类型信息包含如下至少一种信息：目标核心网类型，切换后使用的NAS层，以及，是否更换当前使用的NAS层的指示。
可选的，所述切换指示携带目标核心网的类型信息，可以采用以下任一种表达方式：
方式一：包含显示的核心网类型信息，例如EPC或者NGC。
方式二：包含隐式的指示，例如保持源核心网类型，或者更换核心网类型。示例性地，用一个特定的消息比特位来进行指示，例如0表示目标核心网类型与源核心网类型相同，1表示目标核心网类型与源核心网类型不同，UE需要改变工作的NAS层。可以理解的，若采用该方式，则需要目标基站获取源核心网类型，此时需要在目标核心网设备向目标基站发送的用于切换请求的消息中携带源核心网类型信息。
可选的，所述切换指示携带目标核心网的类型信息，可以采用以下任一可选的方式：
方式一：在现有无线资源控制(radio resource control，RRC)消息类型中，增加目标核 心网的类型信息，比如：
1、对于从LTE基站或eLTE的EPC切换到eLTE的NGC的场景，可以使用RRCConnectionReconfiguration消息作为切换命令(具体消息的名称不做限定，只要是可以用作切换命令的RRC消息即可)，在RRCConnectionReconfiguration消息中的信元(information element，IE)中携带该目标核心网的类型信息，例如，在该RRCConnectionReconfiguration消息中的IE(例如MobilityControlInfo)中携带目标小区标识，以及表示目标核心网类型为NGC的信息。UE收到该RRC消息后，将EPC NAS切换为NGC NAS。可选地，该RRC消息中还可以携带NGC的安全相关的配置信息。需说明的是，所述“eLTE的EPC”表示UE通过该eLTE基站接入核心网类型为EPC的核心网设备。所述“eLTE的NGC”标识UE通过该eLTE基站接入核心网类型为NGC的核心网设备。
2、对于从LTE基站或eLTE的EPC切换到eLTE的EPC的场景，类似的，也可以使用RRCConnectionReconfiguration消息作为切换命令(具体消息的名称不做限定，只要是可以用作切换命令的RRC消息即可)，其中携带目标核心网的类型信息，例如，该消息中的IE(MobilityControlInfo)中携带目标小区标识，以及表示目标核心网类型为EPC的信息。UE收到该RRC消息后，在目标站继续使用EPC NAS。可选的，如果采用未增强的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则默认目标核心网为EPC。
3、对于从NR基站切换到eLTE的EPC场景，可以使用MobilityFromNRCommand消息作为切换命令，其中携带目标核心网的类型信息，例如，该消息中的IE(handover)中携带表示目标制式类型(target RATtype)为eLTE EPC(eutra-epc)的信息，和/或，在给出目标cell标识时携带表示目标核心网类型为EPC的信息。UE收到该消息后，将NGC NAS切换为EPC NAS。可选地，该消息中可以携带EPC的安全相关配置信息。
4、对于从NR基站切换到eLTE的NGC场景，可以使用MobilityFromNRCommand消息作为切换命令，其中携带目标核心网的类型信息，例如，该消息中的IE(handover)中携带表示目标制式类型(targetRAT type)为eLTE NGC(eutra-ngc)的信息，和/或，在给出目标cell标识时携带表示目标核心网类型为NGC的信息。UE收到该消息后，保持使用NGC NAS。
5、对于从eLTE的NGC切换到eLTE的NGC的场景，可以使用RRCConnectionReconfiguration消息作为切换命令，其中携带目标核心网的类型信息，例如，该消息中的IE(MobilityControlInfo)中携带目标小区标识，携带表示目标核心网类型为NGC的信息，UE收到该消息后，保持使用NGC NAS。可选的，如果采用未增强的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则目标核心网与源核心网相同，UE不该变NAS层，保持使用NGC NAS。
6、对于从eLTE的NGC切换到eLTE的EPC的场景，使用RRCConnectionReconfiguration消息作为切换命令，其中携带目标核心网的类型信息，例如，该消息中的IE(MobilityControlInfo)中携带目标小区标识，携带表示目标核心网类型为EPC的信息，UE收到该消息后，将NGC NAS切换为EPC NAS。可选地，该RRC消息中还可以携带EPC的安全相关配置信息。可选的，如果采用未增强的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则默认目标核心网为EPC。
方式二：定义新的RRC消息类型，用于指示源基站和/或目标基站为eLTE的切换场景。可采用如下任一种示例：
1、从LTE基站或eLTE的EPC切换到eLTE的NGC，使用第一RRC消息作为切换命令，用于指示目标核心网类型为NGC，UE收到该消息后，将EPC NAS切换为NGC NAS。可选的，该新定义的第一RRC消息通过其消息中自带的信息，或者对该消息本身的功能定义，来指示目标核心网类型为NGC。可选地，该消息中携带NGC的安全相关配置信息。
2、从LTE基站或eLTE的EPC切换到eLTE的EPC，使用原有的RRCConnectionReconfiguration消息作为切换命令，默认目标核心网类型为EPC，UE收到该消息后，不更换NAS层。
3、从NR基站切换到eLTE的EPC，使用MobilityFromNRCommand消息作为切换命令，默认目标核心网类型为EPC，UE收到该消息后，将NGC NAS切换为EPC NAS。可选地，该消息中携带EPC的安全相关配置信息。
4、从NR基站切换到eLTE的NGC，使用第二RRC消息作为切换命令，用于指示目标核心网类型为NGC，UE收到该消息后，保持使用NGC NAS。可选的，该新定义的第二RRC消息通过其消息中携带的信息，或者对该消息本身的功能定义，来指示目标核心网类型为NGC。
5、从eLTE的NGC切换到eLTE的NGC，使用第一新RRC消息作为切换命令，用于指示目标核心网类型为NGC，UE收到该消息后，保持使用NGC NAS。进一步可选地，该消息中携带NGC的安全相关配置信息。可选的，该新定义的第一新RRC消息通过其消息中携带的信息，或者对该消息本身的功能定义，来指示目标核心网类型为NGC。可选的，如果现有的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则表示目标核心网与源核心网相同，UE不改变NAS层，保持使用NGC NAS。
6、从eLTE的NGC切换到eLTE的EPC，使用第三RRC消息作为切换命令，用于指示目标核心网为EPC，UE收到该消息后，UE收到该消息后，将NGC NAS切换为EPC NAS。进一步可选地，该消息中携带EPC的安全相关配置信息。可选的，该新定义的第三RRC消息通过其消息中携带的信息，或者对该消息本身的功能定义，来指示目标核心网类型为NGC。可选的，如果采用现有的携带MobilityControlInfo的RRCConnectionReconfiguration消息作为切换命令，则表示目标核心网为EPC，UE切换至目标基站后EPC NAS。
可理解的，上述新定义的第一RRC消息、第二RRC消息、第三RRC消息是指与当前定义的用于切换命令的RRC消息(例如LTE中携带MobilityControlInfo的RRCConnectionReconfiguration消息、HandoverfromLTE消息、HandovertoLTE消息)不同的消息，不同具体可以表示为消息标识不同、消息中包含的IE不同、UE收到该消息后与收到现有RRC消息的动作不同等。
S208：UE收到源基站发送的切换指示后，根据其中携带的所述目标核心网的类型信息，在切换至目标基站后使用与目标核心网对应的NAS层。示例性地，若目标核心网与源核心网相同，则保持使用源核心网对应的NAS，若目标核心网与源核心网不同，则停止使用与源核心网对应的NAS，启用目标核心网对应的NAS。具体地，所述UE在RRC层解读切换命令消息，得知切换后需要更换NAS，则指示给目标核心网对应的NAS，可选地，也指示给源核心网对应的NAS。示例性地，上述指示过程可以通过NAS和RRC层之间的层间原语交互实现。
可选地，所述源基站根据UE能力信息以及获取的目标基站的配置信息，确定所述源核心网设备与所述目标核心网设备进行核心网迁移过程，或者确定所述目标核心网的类型信息。。其中，所述UE能力信息用于指示所述UE同时支持源基站制式的业务以及目标基站制式的业务，或者，所述UE能力信息用于指示所述UE支持目标基站制式的目标核心网业务。
可选地，源基站获取目标基站的配置信息的方式可以如下任一种：通过源基站与目标基站之间的接口消息获得，通过源基站与其它邻居基站之间的接口消息获得，OAM配置，以及UE上报(例如ANR中的measurementResult)。具体地，UE可以通过读取邻居基站的广播消息，邻居基站的广播消息携带其核心网的类型信息，从而获知邻居基站的核心网的类型信息，UE将该核心网的类型信息报告给服务基站(例如通过测量报告上报该信息)。示例性地，核心网类型信息可以包含以下信息中的一种或几种的组合：核心网的标识信息，核心网连接指示信息，以及所述核心网的设备为所述邻居基站分配的位置区域标识，所述连接指示信息用于指示所述目标基站与所述目标核心网存在连接。
可选地，所述切换要求消息中还包括切换类型(handover type)指示，该指示指明了源基站到目标基站的切换类型，还可以包含源核心网的类型信息和或目标核心网的类型信息。
可选地，所述切换命令可以携带上述源核心网的类型信息和或目标核心网的类型信息，用于指示UE在后续切换中应用。
可选的，本申请实施例方法所涉及的步骤或者可选设计，可以根据实际需要选取其中的部分或者全部流程动作，以使得方法中涉及的任意两个网元间能够传递该目标核心网设备的类型信息，使得切换过程中涉及的网元能够准确识别目标核心网设备的类型。可以根据需要解决的具体问题的需要来选取其中的步骤，如，当需要在目标基站和目标核心网设备传递目标核心网设备的识别信息时，则，只需要选取步骤204中涉及的方案即可。可选的，本申请实施例涉及的各个网元功能，可分别在具备如下硬件结构的设备运行实现，该硬件结构包括：存储器、收发器和至少一个处理器，该存储器中存储有指令，该存储器、该收发器和该至少一个处理器通过线路互联，该收发器用于执行前述的方法步骤或者各可行设计中(全部或部分)在该网元设备进行的消息收发的操作；该至少一个处理器调用该存储器中存储的该指令，执行前述的方法步骤或者各可行设计中(全部或部分)在该网元设备进行的处理操作。
可选的，本申请实施例涉及的各个网元功能，可分别在具有如下硬件结构的芯片系统运行实现，该芯片系统可应用在前述涉及的网元中，该硬件结构包括：至少一个处理器，存储器和接口电路，该接口电路负责该芯片系统与外界的信息交互，该存储器、该接口电路和该至少一个处理器通过线路互联，该至少一个存储器中存储有指令；该指令被该至少一个处理器执行，以进行前述的方法步骤或者各可行设计中(全部或部分)在该网元设备进行的处理操作。
可选的，本申请实施例涉及的各个网元功能，可分别通过计算机指令来实现，该指令可存储在计算机可读存储介质中，当该指令在计算设备上运行时，以进行前述的方法步骤或者各可行设计中(全部或部分)在该网元设备进行的处理操作。
采用本发明实施例提供的切换方法，源基站在确定将UE切换至目标基站后向所述源核心网设备发送切换要求消息，切换要求消息中包括目标核心网设备的识别信息，所述切换要求消息用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程。本发明实施例提供的技术方案可以适用于目标基站同时支持源核心网及目标核心网的切换场景，通过在切换要求消息中携带目标核心网设备的识别信息，使得源核心网设备能够准确识别目标核心网设备，进而完成核心网迁移，提升切换效率。
以下将以UE从LTE eNB向eLTE eNB切换，即LTE eNB作为源基站，eLTE eNB作为目标基站为例，详细介绍本发明实施例提供的切换方法，本发明的各实施例之间可以相互参考。其中，LTE eNB连接的核心网是EPC，则EPC为源核心网，源核心网设备包括EPC中的MME(下文称为源MME)；eLTE eNB连接的核心网是该EPC及NG-Core，则NG-Core为目标核心网，目标核心网设备包括NG-Core中的设备。
可以理解，本发明实施例提供的切换方法可以适用于UE从源基站向同时支持源核心网及目标核心网的目标基站切换的场景，本发明实施例对源基站及目标基站的具体制式不作任何限定。
图3是本发明实施例提供的切换方法的信令流程示意图，包括步骤S301-S308：
S301：LTE eNB向eLTE eNB发送接口建立请求消息。
其中，上述接口建立请求消息具体可以是X2口建立请求(X2setup request)消息，即LTE eNB与eLTE eNB通过X2口通信。此处认为LTE eNB和eLTE eNB之间重用现有X2接口，也可以使用一个新接口，本发明不限定。
可选地，该接口建立请求消息中包括LTE eNB的配置信息，包括LTE eNB连接的核心网的信息，具体可以是该核心网的标识信息，和/或LTE eNB与该核心网存在连接的指示信 息。可选地，该接口建立请求消息中还可以包括该LTE eNB下的主服务小区的信息或邻区的信息，包括物理小区标识(physical cell identifier，PCI)、全球小区识别码(cell global identification，CGI)等信息，在此不做赘述。
S302：eLTE eNB收到接口建立请求信息后，向LTE eNB发送接口建立响应信息，该接口建立响应信息消息中包括eLTE eNB的配置信息。
其中，上述接口建立响应消息具体可以是X2口建立响应(X2setup response)消息。
可选地，所述eLTE eNB的配置信息中包括该eLTE eNB连接的一个或多个核心网的信息，具体可以是所述核心网的标识信息，和/或eLTE eNB与各个核心网存在连接的连接指示信息等，用于告知LTE eNB其核心网连接情况。其中，eLTE eNB连接的一个或多个核心网的信息可以eLTE eNB支持的所有类型的核心网的信息，包括源核心网的信息；也可以是eLTE eNB支持的除源核心网之外的其他核心网的信息。
例如，eLTE eNB分别连接了NG-Core和EPC，LTE eNB向eLTE eNB发送了X2setup request消息，那么eLTE eNB在X2setup response消息中可以包括eLTE eNB连接NG-Core的连接指示信息、NG-Core的标识信息(next-generation Core IDentity,NG-Core ID)中的一种或多种信息；可选地，还可以包括eLTE eNB连接EPC的连接指示信息和/或该EPC的标识信息。
假设NG-Core中包含类似MME和S-GW的实体，则NG-Core的标识信息可以是MME ID或者S-GW ID。
可选地，eLTE eNB可以连接多个NG-Core，则上述X2setup request消息中可以携带每个NG-Core的信息。
可选地，上述配置信息中还可以包括eLTE eNB连接的各个NG-Core的负载信息，所述负载信息可以用于LTE eNB决策是否发起核心网迁移过程以及选择适合的NG-Core进行核心网迁移。
可选地，上述负荷信息还可以通过资源状态更新(resource status update)消息进行传输给LTE eNB。
可以理解，每个核心网下可以连接多个基站设备，每个基站设备都能获取所连接的核心网的信息。
可选地，作为本发明的一个实施方式，eLTE eNB有两种位置区域标识，由EPC分配的TAI，或称位置区域码(tracking area code，TAC)，以及由NG-Core分配的MAI，TAI与MAI可以采用不同的格式，或者MAI采用与TAI相同的格式。MAI及TAI均可以包含在上述eLTE eNB的配置消息中发送给LTE eNB。可选地，若eLTE eNB只有EPC分配的TAI，即在New RAT接入网中采用与LTE接入网相同的位置区域划分，则eLTE eNB也可以不将其所配置的TAI发送给LTE eNB。
可选地，在本发明的另一实施方式中，若LTE eNB与eLTE eNB之间的通信接口已经建立，eLTE eNB也可以通过基站配置更新(configuration update)消息将包含NG-Core相关信息的配置信息发送给LTE eNB。当eLTE eNB检测到自身的配置信息有变化时，就可以通过该消息通知LTE eNB，在该消息中携带更新后的配置信息，例如，更新后的NG-Core相关信息。
当源基站即LTE eNB与目标基站即eLTE eNB完成接口建立或者配置信息更新过程之后，双方基站均获取了对方基站的配置信息，包括对方支持的核心网的信息。进而，LTE eNB可以根据获取到的eLTE eNB的配置信息决定进行核心网迁移。具体地，核心网迁移过程包括步骤S303-S3011：
S303：LTE eNB确定将UE切换到eLTE eNB。
具体地，LTE eNB可以根据UE上报的测量报告或者通过测量配置获取到UE的相关测量信息，决定UE要切换的目标基站，即确定eLTE eNB为目标基站。
可选地，在本发明的一个实施方式中，LTE eNB还可以获取到UE的能力信息，所述UE 能力信息用于指示所述UE同时支持源基站制式的业务以及目标基站制式的业务。LTE eNB可以根据所述UE能力信息以及在接口建立过程中或者在基站配置更新过程中获取的eLTE eNB的配置信息，确定与eLTE eNB接入的NG-Core，即目标核心网设备进行核心网迁移过程。具体地，LTE eNB可以根据eLTE eNB的配置信息中的连接指示信获知eLTE eNB连接了NG-Core，进而根据核心网负荷信息确定该NG-Core是否适合切换；或者，LTE eNB可以根据核心网标识信息直接识别该NG-Core。
S304：LTE eNB发送切换要求消息到源MME，该切换要求消息中包括目标核心网的识别信息，所述切换要求消息用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程。
所述目标核心网的识别信息包括目标eLTE eNB的位置区域标识，核心网的标识信息，核心网迁移指示信息中的一种或多种信息。
其中，源MME作为源核心网中负责信令处理的设备，接收并处理LTE eNB发送的切换要求消息。
可选地，若eLTE eNB被配置了TAI及MAI，LTE eNB获取的eLTE eNB的配置信息中包含NG-Core为eLTE eNB分配的MAI、NG-Core ID，以及指示eLTE eNB与NG-Core存在连接的连接指示信息，则eLTE eNB的识别信息中包含MAI、NG-Core ID以及连接指示信息中的任意一个或多个。可选地，上述配置信息中还可以包括EPC为eLTE eNB分配的TAI。通过上述任意一种识别信息，源核心网设备可以搜索到对应的目标核心网设备。
可选地，若eLTE eNB仅被配置了TAI，LTE eNB获取的eLTE eNB的配置信息中包含NG-Core ID，以及连接指示信息，则eLTE eNB的识别信息中包含NG-Core ID和/或连接指示信息。可选地，该配置信息中还可以包括eLTE eNB被分配到的TAI。
可选地，所述目标核心网设备的识别信息可以包含在现有的切换请求消息的信元(information element，IE)，例如target ID信元中，也可以包含在一个新的信元中。
可选地，如果eLTE eNB连接多个NG-Core，LTE eNB可以根据所获取的各个NG-Core的负荷信息，选择适合切换的NG-Core即确定目标NG-Core，并把相应的核心网信息写入切换要求消息中。
可选地，切换要求消息中还可以包括切换类型信息，用于指明核心网迁移的类型为LTE到New RAT，具体地，可以在现有的handover type信元中增加一个新的类型，例如“LTEtoNR”，或者“LTEto5G”等，本发明实施例对此命名不做限定。
可选地，切换要求消息中还可以包括核心网迁移指示信息，用于指示源核心网进行核心网迁移。具体地，若切换要求消息中包含上述切换类型信息，可以将切换类型信息作为一个显示的核心网迁移指示；或者独立设置一个指示位，对此不做限定。
S305：源MME根据切换要求消息，搜索到目标核心网设备。
具体地，源MME从切换要求消息中检测到LTE eNB发出的核心网重配置请求，根据切换要求消息中的目标核心网设备的识别信息，可以找到目标NG-Core，并准备向该NG-Core发送前向重配置请求(forward relocation request)消息。
可选地，若上述识别信息中包含NG-Core ID，则根据NG-Core ID，可以直接确定目标NG-Core。
可选地，若上述识别信息中包含MAI，则源MME通过检索数据库，可以确定该MAI对应的NG-Core。
可选地，若上述识别信息中仅包含连接指示信息，则源MME可以获知目标基站与源核心网之外的核心网存在连接，进而，源MME可以根据handover type中的类型确定是跨制式切换，然后在目标制式的核心网中随机选择一个目标核心网。例如，源MME可以确定UE的切换是从LTE小区到NEW RAT小区的切换，则源MME可以随机选择一个NG-Core。
S306：源MME向目标NG-Core发送前向重配置请求(forward relocation request)消息。
可选地，假设NG-Core类似EPC，具有类似MME、S-GW以及P-GW等设备，则前向重 配置请求将发送至目标MME，目标MME检测到目标S-GW的变化，将发起创建会话(create session)流程，在目标S-GW中为UE创建一个承载资源。
S307：NG-Core向eLTE eNB发送重配置请求(relocation request)消息，通知eLTE eNB预留资源。
具体地，如果NG-Core中具有类似MME、S-GW以及P-GW等设备，则由目标MME发送上述重配置请求消息到eLTE eNB。
S308：eLTE eNB根据接收到的重配置请求消息，为UE预留资源。
可选地，eLTE eNB预留资源后，向NG-Core发送重配置请求响应(relocation request ack)消息。
S309：NG-Core向源MME发送前向重配置响应(forward relocation response)消息。
其中，目标核心网需要为切换期间从源核心网到目标核心网之间的下行数据表，在目标核心网中创建一个转发通道。具体地，如果NG-Core中具有类似MME、S-GW以及P-GW等设备，NG-Core需要为切换期间从源S-GW到目标S-GW之间的下行数据包，在目标S-GW中创建一个数据转发通道，当数据转发通道建立完成后，由目标MME将上述前向重配置响应发送给源MME。
S3010：源MME向LTE eNB发送切换命令(handover command)消息。
S3011：LTE eNB向UE转发上述发送切换命令消息。
具体地，UE成功接收到上述切换命令消息发送表示核心网迁移过程完成。UE接收到上述切换消息后，发起切换流程，关于具体地切换过程在此不做赘述。
在该实施例中，由源基站决策是否进行核心网迁移，通过接口建立过程或者基站配置信息更新过程获取目标基站所连接核心网的相关信息，例如核心网标识信息以及连接指示信息，确定目标核心网设备，从而准确完成UE从源基站到目标基站的切换。
可选地，在本发明的另一个实施例中，可以由目标基站确定是否进行核心网迁移。以下仍以UE从LTE eNB切换到eLTE eNB，且eLTE eNB同时支持EPC及NG-Core为例进行说明。
图4是由eLTE eNB决策进行核心网迁移的信令流程示意图，包括步骤S401-S404：
S401：LTE eNB决定要进行基站切换。
具体地，源基站可以根据接收到的UE的测量报告决定目标基站为eLTE eNB。
S402：LTE eNB向eLTE eNB发送接口切换请求消息。
具体地，接口切换请求消息可以是X2口切换请求(X2handover request)消息。可选地，所述接口切换请求消息中包含LTE eNB的配置信息。
在该实施例中，由eLTE eNB确定进行核心网迁移。具体地，eLTE eNB可以根据UE能力信息以及eLTE eNB的配置信息确定进行核心网迁移，所述eLTE eNB的配置信息中包括eLTE eNB支持的核心网的信息，例如核心网的标识信息、eLTE eNB与至少一个核心网存在连接的连接指示信息以及各个核心网的负荷信息等。若eLTE eNB支持多个同类型的核心网，可以根据各核心网的负荷，选择一个目标核心网，或者随机选择一个目标核心网。其中，eLTE eNB可以通过LTE eNB发送的切换请求消息获取上述UE能力信息，所述UE能力信息用于指示所述UE同时支持源基站制式的业务以及目标基站制式的业务。
S403：eLTE eNB确定进行核心网迁移后，向LTE eNB发送接口切换请求响应消息。
其中，所述接口切换请求响应消息用于指示所述源基站向所述源核心网设备发送所述切换要求消息。所述接口切换请求响应消息中包含eLTE eNB确定进行核心网迁移的决策结果，包括目标核心网标的识信息、核心网迁移指示信息以及位置区域标识等一种或多种信息。
可选地，所述切换请求响应消息也可以包含eLTE eNB的配置信息，LTE eNB收到后，LTE eNB可以进一步决策所要迁移的核心网，关于eLTE eNB的配置信息的具体内容可以参照本发明其他实施例的相关内容，在此不做赘述。
S404：LTE eNB根据接收到的eLTE eNB决策结果，向源核心网设备(图中示为源MME)， 发送切换要求消息，指示源核心网设备向目标核心网设备(图中示为NG-Core)，发起核心网迁移过程。
具体地，LTE eNB可以在发送给源核心网设备即源MME的切换要求消息中携带目标核心网的识别信息，关于目标核心网的识别信息可以参照本发明其他实施例的相关内容，在此不做赘述。
源核心网设备接收切换要求消息之后的具体核心网迁移过程以及UE切换过程的详细描述可以参照图3所示实施例的相关内容，例如S305-S3011的描述，在此不做赘述。
在该实施例中，由目标基站决策是否发起核心网迁移过程，进而在接口切换过程中交互基站的配置信息，最终完成UE的切换过程。由于目标基站可以及时获取目标核心网的信息，能够提升决策的准确性，进而提升切换效率。该实施例可以适用于源基站与目标基站之间的接口已经建立的场景。
图5是本发明实施例提供的一种基站的结构示意图。
该基站可以作为UE切换过程中的源基站，该基站与源核心网设备相连接。
该基站包括：处理单元501，用于确定将UE切换至目标基站，所述目标基站分别与所述源核心网设备以及目标核心网设备相连接。
关于确定目标基站的过程可以参照本发明方法部分实施例的相关描述，在此不做赘述。
第一发送单元502，向所述源核心网设备发送切换要求消息，所述切换要求消息中包括目标核心网设备的识别信息，所述切换要求消息用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程。
可选地，所述基站还包括第一获取单元503，用于从所述目标基站获取所述目标基站的配置信息，所述配置信息中包括与所述目标基站相连接的核心网设备的标识信息和/或指示所述目标基站与该核心网设备存在连接的指示信息。
可选地，所述基站还包括第二发送单元504，用于向所述目标基站发送接口切换请求消息，所述接口切换请求消息中包括UE能力信息，以使得所述目标基站根据所述UE能力信息以及所述目标基站的配置信息确定所述源核心网设备与所述目标核心网设备进行核心网迁移过程，所述UE能力信息用于指示所述UE同时支持源基站制式的业务以及目标基站制式的业务；所述第一获取单元503具体用于从所述目标基站接收接口切换请求响应消息，所述接口切换请求响应消息中包含所述目标基站的配置信息，所述接口切换请求响应消息用于指示所述源基站向所述源核心网设备发送所述切换要求消息。其中，关于目标基站确定进行核心网迁移的过程可以参照本发明方法部分实施例的相关内容，在此不做赘述。
可选地，所述第二发送单元504还用于，向所述目标基站发送接口连接建立请求消息，所述连接建立请求消息中包括所述源基站的配置信息；所述第一获取单元503具体用于从所述目标基站接收接口连接建立响应消息，所述连接建立响应消息中包括所述目标基站的配置信息。
可选地，第一获取单元503具体用于，从所述目标基站接收基站配置更新消息，所述基站配置更新消息中包括更新的所述目标基站的配置信息。
关于目标基站的配置信息的具体内容，以及获取目标基站的配置信息的过程的详细描述可以参见本发明方法部分的相关内容，在此不做赘述。
可选地，所述目标核心网设备的识别信息包括所述目标核心网的标识信息和/或连接指示信息；其中，所述连接指示信息用于指示所述目标基站与所述目标核心网存在连接。
可选地，作为本发明的一个实施方式，所述配置信息中还包括与所述目标基站相连接的核心网设备为所述目标基站分配的位置区域标识。关于位置区域标识的具体内容可以参照本发明方法部分实施例的相关描述，在此不做赘述。在该实施例中，所述目标核心网设备的识别信息包括如下任意一个或多个信息的组合：所述目标核心网的标识信息，连接指示信息，以及所述目标核心网设备为所述目标基站分配的位置区域标识；其中，所述连接指示信息用于指示所述目标基站与所述目标核心网存在连接。
关于目标核心网设备的识别信息的详细内容及发送过程可以参照本发明方法部分实施例的相关描述，在此不做赘述。
可选地，作为本发明的一个实施方式，所述基站还包括第二获取单元505，用于获取UE能力信息，所述UE能力信息用于指示所述UE同时支持源基站制式的业务以及目标基站制式的业务；所述处理单元501还用于，根据所述UE能力信息以及所述目标基站的配置信息，确定所述源核心网设备与所述目标核心网设备进行核心网迁移过程。其中，关于所述基站确定进行核心网迁移的过程可以参照本发明方法部分实施例的相关内容，在此不做赘述。
如图5所示，该基站中的各单元之间可以通过通信总线的方式相互连接。图中未示，该基站内的各单元也可以采用其他连接方式连接，本发明实施例对此不做特别限定。
在本发明的另一个实施例中，在硬件实现上，可以由一个处理器执行处理单元501的功能，可以由一个发送器执行第一发送单元502的功能，该发送器可以位于所述基站的通信模块中，所述通信模块可以支持所述基站与其他网络设设备进行通信。其中，处理单元502可以以硬件形式内嵌于或独立于基站的处理器中，也可以以软件形式存储于基站的存储器中，以便于处理器调用执行以上各个模块对应的操作。
需要说明的是，当所述基站还包括第一获取单元503时，可以由一个接收器执行第一获取单元503的功能；当所述基站还包括第二发送单元504时，第二发送单元504与第一发送单元502可以是独立的两个具有发送功能的硬件装置，例如是两个独立的发送器,所述两个发送器可以位于所述基站的通信模块内；又例如第一发送单元502是所述基站与核心网设备之间的接口；当所述基站还包括第二获取单元505时，第二获取单元505与第一获取单元503可以是独立的两个具有接收功能的硬件装置，例如是两个独立的接收器，所述两个接收器可以位于所述基站的通信模块内。
在一个实施方式中，第一获取单元503与第二发送单元504的功能可以由所述基站与其他基站设备间的通信接口实现；第二获取单元505的功能可以由基站的收发信机实现；或第一发送单元502的功能可以由所述基站与核心网设备间的通信接口实现。
图6示出了上述实施例中涉及到的一种基站的一种可能的设计结构的简化示意图。所述控制设备可以作为UE切换的源基站。
所述基站包括：处理器601用于对控制设备的动作进行控制管理，执行各种功能来支持控制设备提供的通信服务。例如，处理器601用于支持控制设备执行图2-3中源基站执行的操作，和/或用于本文所描述的技术的其他由源基站执行的过程。
存储器602用于存储用于所述基站进行本发明实施例提供的切换方法的程序代码和数据,该程序代码包括计算机操作指令。存储器602中存储的程序代码可以由处理器601执行。
发射器/接收器604用于支持基站与UE通信。
通信模块603用于支持基站与其他网络实体的通信，例如与核心网设备或其他基站设备的通信，可以包括基站与其他基站之间的通信接口，以及基站与核心网设备之间的通信接口。
可以理解的是，图6仅仅示出了控制设备的简化设计。在实际应用中，控制设备可以包含任意数量的发射器，接收器，处理器，控制器，存储器，通信模块等，在此不做赘述。
采用图5或图6实施例所示的基站，通过在切换要求消息中携带目标核心网设备的识别信息，使得源核心网设备能够准确识别目标核心网设备，进而完成核心网迁移，提升切换效率。进而，该实施例提供的基站作为源基站决策是否进行核心网迁移，通过接口建立过程或者基站配置信息更新过程获取目标基站所连接核心网的相关信，确定目标核心网设备，从而准确完成UE从源基站到目标基站的切换。
如图7所示，本发明实施例提供了一种基站。
该基站可以作为UE切换过程中的目标基站，该基站同时连接目标核心网及源核心网，其中，源核心网还与源基站连接。
该基站包括：处理单元701，用于确定目标核心网设备。
具体地，当该基站同时连接多个与目标核心网类型相同的核心网时，处理单元701可以根据各个核心网的负载，选择负载最轻的核心网作为目标核心网。
发送单元702，用于向源基站发送指示消息，所述指示消息用于所述源核心网设备与所述目标核心网设备进行核心网迁移过程。
可选地，所述指示消息可以是接口切换请求响应消息，所述接口切换请求响应消息中包含所述目标基站的配置信息。关于目标基站的配置信息的具体内容可以参照本发明其他实施例的相关内容，不做赘述。具体地，在该实施例中，所述基站还包括接收单元703，用于接收所述源基站发送的接口切换请求消息，所述接口切换请求消息中包括UE能力信息，所述UE能力信息用于指示所述UE同时支持源基站制式的业务以及目标基站制式的业务；所述处理单元701具体用于根据所述UE能力信息以及所述目标基站的配置信息确定所述源核心网设备与所述目标核心网设备进行核心网迁移过程；所述发送单元702具体用于向所述源基站发送所述接口切换请求响应消息。
可选地，所述指示信息可以是处理单元701确定的目标核心网设备的标识信息，则接收到该目标核心网设备的标识信息的源基站可以在向源核心网设备发送的切换要求消息中携带该目标核心网设备的标识信息。所述指示信息也可以是独立设置的指示位，本发明实施例对此不做限定。
关于所述基站确定核心网迁移过程的具体描述可以参照本发明其他实施例的相关内容，不做赘述。
如图7所示，该基站中的各单元之间可以通过通信总线的方式相互连接。图中未示，该基站内的各单元也可以采用其他连接方式连接，本发明实施例对此不做特别限定。
在本发明的另一个实施例中，在硬件实现上，可以由一个处理器执行处理单元701的功能，可以由一个发送器执行发送单元702的功能，可以由一个接收器执行接收单元703的功能，其中，处理单元701可以以硬件形式内嵌于或独立于基站的处理器中，也可以以软件形式存储于基站的存储器中，以便于处理器调用执行以上各个模块对应的操作。可以理解，该基站的实际结构设计也可以参照图5所示的基站设计，不做赘述。
采用本发明实施例提供的基站，可以实现由目标基站决策是否进行核心网迁移过程并选择目标核心网，决策准确率高，进而在切换过程中交互基站的配置信息，高效完成UE的切换过程。
图8是本发明实施例提供的一种核心网设备的结构示意图。
该核心网设备分别与源基站及目标基站相连接，其中，目标基站还与目标核心网设备相连接，且UE确定从源基站切换到目标基站。
该核心网设备包括：接收单元801，用于从源基站接收切换要求消息，所述切换要求消息中包括目标核心网设备的识别信息，所述切换要求消息用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程。
处理单元802，用于根据所述切换要求消息，确定所述目标核心网设备；
发送单元803，用于向所述目标核心网设备发送前向重配置请求消息，所述前向重配置请求消息用于指示目标核心网设备为UE创建承载资源。
具体地，接收到所述前向重配置请求消息的目标核心网向目标基站发送重定位请求消息，以通知所述目标基站为所述UE预留资源。
该核心网设备可以执行图2-图3所示实施例中源核心网设备执行的步骤，关于各功能模块的具体功能描述可以参照相应的方法实施例步骤，在此做赘述。
在本发明的另一个实施例中，在硬件实现上，可以由一个接收器执行接收单元801的功能，可以由一个处理器执行处理单元802的功能，可以由一个发送器执行发送单元803的功能，其中，处理单元802可以以硬件形式内嵌于或独立于基站的处理器中，也可以以软件形式存储于基站的存储器中，以便于处理器调用执行以上各个模块对应的操作。
图9是本发明实施例提供的核心网设备的一种可能的设计结构的简化示意图。
如图9所示，该核心网设备可以包括：收发器901，处理器902，图中还示出了存储器903和总线904，其中，收发器901、处理器902、存储器903通过总线904连接并完成相互间的通信。
其中，收发器901可以是通信接口，该通信接口该通信接口可以与接入网设备的对应通信接口直接或间接相连，用于接入网与核心网之间的信息交互。
处理器902可以用于执行图2至图5所示方法实施例中涉及核心网设备的处理过程和/或用于本申请所描述的技术的其他过程。
存储器903用于存储可执行程序代码或数据，该程序代码包括计算机操作指令。存储器903中存储的程序代码可以由处理器902执行。
关于该实施例中核心网设备执行的方法流程描述，以及该设备内各装置或元器件的具体功能可以参照本发明其他实施例的相关内容，在此不做赘述。
本发明实施例对核心网设备的具体类型不做特别限定，可以是MME，或多个核心网设备的任意组合。
图10是本发明实施例提供的一种通信系统的示意图，该通信系统包括源基站1001，目标基站1002，源核心网设备1003，及目标核心网设备1004。
如图10所示，源基站1001与源核心网设备1003连接；目标基站与源核心网设备1003、目标核心网设备1004分别连接；此外，源基站1001与目标基站1002之间可以存在通信接口。
关于上述通信系统中的各设备的功能及执行的步骤的详细描述，可以参照本发明其他实施例的相关内容，例如，源基站1001可以是图4或图5所示的基站，可以执行图2-图3所示实施例中源基站或LTE eNB执行的步骤；目标基站1002可以是图6所示的基站，可以执行图2-图3所示实施例中目标基站或eLTE eNB执行的步骤，在此不做赘述。
采用本发明实施例提供的通信系统，源基站在确定将UE切换至目标基站后向所述源核心网设备发送切换要求消息，切换要求消息中包括目标核心网设备的识别信息，所述切换要求消息用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程，其中，目标基站同时支持源核心网及目标核心网。通过在切换要求消息中携带目标核心网设备的识别信息，使得源核心网设备能够准确识别目标核心网设备，进而完成核心网迁移，提升切换效率。
本申请还提供了如下实施例：
实施例1：一种切换方法，包括：源基站确定将用户设备UE切换至目标基站，其中，该源基站与源核心网设备相连接，该目标基站分别与该源核心网设备以及目标核心网设备相连接；
该源基站向该源核心网设备发送切换要求消息，该切换要求消息中包括目标核心网设备的识别信息，该切换要求消息用于指示该源核心网设备与该目标核心网设备进行核心网迁移过程。
实施例2：根据实施例1所述的方法，还包括：该源基站从该目标基站获取该目标基站的配置信息，该配置信息中包括与该目标基站相连接的核心网设备的标识信息和/或指示该目标基站与该核心网设备存在连接的指示信息。
实施例3：根据实施例2所述的方法，该目标核心网设备的识别信息包括该目标核心网的标识信息和/或连接指示信息；其中，该连接指示信息用于指示该目标基站与该目标核心网存在连接。
实施例4：根据实施例2所述的方法，该配置信息中还包括与该目标基站相连接的核心网设备为该目标基站分配的位置区域标识。
实施例5：根据实施例4所述的方法，该目标核心网设备的识别信息包括如下任意一个或多个信息的组合：该目标核心网的标识信息，连接指示信息，以及该目标核心网设备为 该目标基站分配的位置区域标识；
其中，该连接指示信息用于指示该目标基站与该目标核心网存在连接。
实施例6：根据实施例1-5任一所述的方法，还包括：
该源基站获取UE能力信息，该UE能力信息用于指示该UE同时支持源基站制式的业务以及目标基站制式的业务；该源基站根据该UE能力信息以及该目标基站的配置信息，确定该源核心网设备与该目标核心网设备进行核心网迁移过程。
实施例7：根据实施例1-5任一所述的方法，该方法还包括，
该源基站向该目标基站发送接口切换请求消息，该接口切换请求消息中包括UE能力信息，以使得该目标基站根据该UE能力信息以及该目标基站的配置信息确定该源核心网设备与该目标核心网设备进行核心网迁移过程，该UE能力信息用于指示该UE同时支持源基站制式的业务以及目标基站制式的业务；该源基站从该目标基站接收接口切换请求响应消息，该接口切换请求响应消息中包含该目标基站的配置信息，该接口切换请求响应消息用于指示该源基站向该源核心网设备发送该切换要求消息。
实施例8：根据实施例1-5任一所述的方法，该源基站从该目标基站获取该目标基站的配置信息包括：
该源基站向该目标基站发送接口连接建立请求消息；该源基站从该目标基站接收接口连接建立响应消息，该连接建立响应消息中包括该目标基站的配置信息。
实施例9：根据实施例1-5任一所述的方法，该源基站从该目标基站获取该目标基站的配置信息包括，
该源基站从该目标基站接收基站配置更新消息，该基站配置更新消息中包括更新的该目标基站的配置信息。
实施例10：一种基站，包括：处理单元，用于确定将用户设备UE切换至目标基站，其中，该源基站与源核心网设备相连接，该目标基站分别与该源核心网设备以及目标核心网设备相连接；第一发送单元，用于向该源核心网设备发送切换要求消息，该切换要求消息中包括目标核心网设备的识别信息，该切换要求消息用于指示该源核心网设备与该目标核心网设备进行核心网迁移过程。
实施例11：根据实施例10所述的基站，还包括：第一获取单元，用于从该目标基站获取该目标基站的配置信息，该配置信息中包括与该目标基站相连接的核心网设备的标识信息和/或指示该目标基站与该核心网设备存在连接的指示信息。
实施例12：根据实施例11所述的基站，该目标核心网设备的识别信息包括该目标核心网的标识信息和/或连接指示信息；其中，该连接指示信息用于指示该目标基站与该目标核心网存在连接。
实施例13：根据实施例11所述的基站，该配置信息中还包括与该目标基站相连接的核心网设备为该目标基站分配的位置区域标识。
实施例14：根据实施例13所述的基站，该目标核心网设备的识别信息包括如下任意一个或多个信息的组合：该目标核心网的标识信息，连接指示信息，以及该目标核心网设备为该目标基站分配的位置区域标识；其中，该连接指示信息用于指示该目标基站与该目标核心网存在连接。
实施例15：根据实施例10-14任一所述的基站，还包括：
第二获取单元，用于获取UE能力信息，该UE能力信息用于指示该UE同时支持源基站制式的业务以及目标基站制式的业务；该处理单元还用于，该源基站根据该UE能力信息以及该目标基站的配置信息，确定该源核心网设备与该目标核心网设备进行核心网迁移过程。
实施例16：根据实施例10-14任一所述的基站，还包括：
第二发送单元，用于向该目标基站发送接口切换请求消息，该接口切换请求消息中包括UE能力信息，以使得该目标基站根据该UE能力信息以及该目标基站的配置信息确定该源核心网设备与该目标核心网设备进行核心网迁移过程，该UE能力信息用于指示该UE同 时支持源基站制式的业务以及目标基站制式的业务；该第一获取单元，具体用于从该目标基站接收接口切换请求响应消息，该接口切换请求响应消息中包含该目标基站的配置信息，该接口切换请求响应消息用于指示该源基站向该源核心网设备发送该切换要求消息。
实施例17：根据实施例10-14任一所述的基站，还包括：第二发送单元，用于向该目标基站发送接口连接建立请求消息；该第一获取单元，具体用于从该目标基站接收接口连接建立响应消息，该连接建立响应消息中包括该目标基站的配置信息。
实施例18：根据实施例10-14任一所述的基站，该第一获取单元具体用于，从该目标基站接收基站配置更新消息，该基站配置更新消息中包括更新的该目标基站的配置信息。
可以理解，本发明实施例中基站或者核心网设备中使用的处理器可以是中央处理器(CPU)，通用处理器、数字信号处理器(DSP)、专用集成电路(ASIC)，现场可编程门阵列(FPGA)或者其他可编程逻辑器件、晶体管逻辑器件，硬件部件或者其任意组合。其可以实现或执行结合本发明公开内容所描述的各种示例性的逻辑方框，模块和电路。所述处理器也可以是实现计算功能的组合，例如包含一个或多个微处理器组合，DSP和微处理器的组合等等。
本发明实施例所述的总线可以是工业标准体系结构(Industry Standard Architecture，ISA)总线、外部设备互连(Peripheral Component，PCI)总线或扩展工业标准体系结构(Extended Industry Standard Architecture，EISA)总线等。总线可以分为地址总线、数据总线、控制总线等。为便于表示，本发明附图中的总线仅用一条粗线表示，但并不表示仅有一根总线或一种类型的总线。
本所属领域的技术人员可以清楚地了解到，本发明提供的各实施例的描述可以相互参照，为描述的方便和简洁，例如关于本发明实施例提供的各装置、设备的功能以及执行的步骤可以参照本发明方法实施例的相关描述。
结合本发明公开内容所描述的方法或者算法的步骤可以硬件的方式来实现，也可以是由处理器执行软件指令的方式来实现。软件指令可以由相应的软件模块组成，软件模块可以被存放于RAM存储器、闪存、ROM存储器、EPROM存储器、EEPROM存储器、寄存器、硬盘、移动硬盘、CD-ROM或者本领域熟知的任何其它形式的存储介质中。一种示例性的存储介质耦合至处理器，从而使处理器能够从该存储介质读取信息，且可向该存储介质写入信息。当然，存储介质也可以是处理器的组成部分。处理器和存储介质可以位于ASIC中。另外，该ASIC可以位于用户设备中。当然，处理器和存储介质也可以作为分立组件存在于用户设备中。
在本申请所提供的几个实施例中，应该理解到，所揭露的系统、设备和方法，在没有超过本申请的范围内，可以通过其他的方式实现。例如，以上所描述的实施例仅仅是示意性的，例如，所述模块或单元的划分，仅仅为一种逻辑功能划分，实际实现时可以有另外的划分方式，例如多个单元或组件可以结合或者可以集成到另一个系统，或一些特征可以忽略，或不执行。其中所述作为分离部件说明的单元可以是或者也可以不是物理上分开的，作为单元显示的部件可以是或者也可以不是物理单元，即可以位于一个地方，或者也可以分布到多个网络单元上。可以根据实际的需要选择其中的部分或者全部模块来实现本实施例方案的目的。本领域普通技术人员在不付出创造性劳动的情况下，即可以理解并实施。
另外，所描述系统、设备和方法以及不同实施例的示意图，在不超出本申请的范围内，可以与其它系统，模块，技术或方法结合或集成。另一点，所显示或讨论的相互之间的耦合或直接耦合或通信连接可以是通过一些接口，装置或单元的间接耦合或通信连接，可以是电子、机械或其它的形式。
以上所述，仅为本发明的具体实施方式，但本发明的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本发明揭露的技术范围内，可轻易想到变化或替换，都应涵盖在本发明的保护范围之内。因此，本发明的保护范围应所述以权利要求的保护范围为准。

Claims (19)

  1. 一种切换方法，其特征在于，包括：
    将用户设备UE从源基站向目标基站切换过程中，
    所述源基站向所述源核心网设备发送用于切换要求的消息，所述消息中包括所述目标核心网设备的识别信息，所述目标核心网设备的识别信息被用于指示所述源核心网设备与所述目标核心网设备进行核心网迁移过程；
    所述源基站与所述源核心网设备相连接，所述目标基站与所述源核心网设备以及所述目标核心网设备分别具有连接。
  2. 根据权利要求1所述的方法，其特征在于，所述方法还包括：
    所述源基站从所述目标基站获取所述目标基站的配置信息，
    所述配置信息包括如下至少一种：与所述目标基站相连接的核心网设备的标识信息，以及，所述目标基站与所述核心网设备存在连接的指示信息。
  3. 根据权利要求1或2中任一所述的方法，其特征在于，
    所述目标核心网设备的识别信息包括如下至少一种：所述目标核心网的标识信息，以及，连接指示信息；
    其中，所述连接指示信息用于指示所述目标基站与所述目标核心网存在连接。
  4. 根据权利要求2所述的方法，其特征在于，所述配置信息中还包括：与所述目标基站相连接的核心网设备为所述目标基站分配的位置区域标识。
  5. 根据权利要求4所述的方法，其特征在于，所述目标核心网设备的识别信息包括如下任意一个或任意多个信息的组合：
    所述目标核心网的标识信息，连接指示信息，以及所述目标核心网设备为所述目标基站分配的位置区域标识；
    其中，所述连接指示信息用于指示所述目标基站与所述目标核心网存在连接。
  6. 根据权利要求1-5任一所述的方法，其特征在于，所述方法还包括：
    所述源基站获取UE能力信息，所述UE能力信息用于指示所述UE同时支持源基站制式的业务以及目标基站制式的业务；
    所述源基站根据所述UE能力信息以及所述目标基站的配置信息，确定所述源核心网设备与所述目标核心网设备进行核心网迁移过程。
  7. 根据权利要求1-5任一所述的方法，其特征在于，所述方法还包括，
    所述源基站向所述目标基站发送接口切换请求消息，所述接口切换请求消息中包括UE能力信息，所述UE能力信息用于指示所述UE支持源基站制式的业务以及目标基站制式的业务；和/或
    所述源基站从所述目标基站接收接口切换请求响应消息，所述接口切换请求响应消息中包含所述目标基站的配置信息，所述接口切换请求响应消息用于指示所述源基站向所述源核心网设备发送所述用于切换要求的消息。
  8. 根据权利要求1-5任一所述的方法，其特征在于，所述源基站从所述目标基站获取所述目标基站的配置信息，包括：
    所述源基站向所述目标基站发送接口连接建立请求消息；
    所述源基站从所述目标基站接收接口连接建立响应消息，所述连接建立响应消息中包括所述目标基站的配置信息。
  9. 根据权利要求1-5任一所述的方法，其特征在于，所述源基站从所述目标基站获取所述目标基站的配置信息包括：
    所述源基站从所述目标基站接收基站配置更新消息，所述基站配置更新消息中包括更新的所述目标基站的配置信息。
  10. 一种切换方法，其特征在于，包括：
    在源基站将用户设备向目标基站切换的过程中，
    所述源基站向所述用户设备发送切换指示，所述切换指示携带目标核心网的类型信息。
  11. 根据权利要求10所述的方法，其特征在于，目标核心网的类型信息，用于表示所述用户设备切换至所述目标基站后需使用与所述目标核心网对应的NAS层进行后续流程。
  12. 根据权利要求10或11中任一所述的方法，其特征在于，还包括：
    所述源基站接收源核心网发送的用于切换的消息，所述用于切换的消息中携带所述切换指示。
  13. 根据权利要求10-12中任一所述的方法，其特征在于，所述目标核心网的类型信息包含如下至少一种：目标核心网的类型，切换后使用的NAS层，以及，是否变更当前使用的NAS层的指示。
  14. 根据权利要求10-13中任一所述的方法，所述切换指示为无线资源控制消息，所述无线资源控制消息中携带所述目标核心网的类型信息。
  15. 一种基站，其特征在于，包括：存储器、收发器和至少一个处理器，所述存储器中存储有指令，所述存储器、所述收发器和所述至少一个处理器通过线路互联，所述收发器用于执行权利要求1-14任一所述的方法中，在所述基站进行的信息收发的操作；
    所述至少一个处理器调用所述存储器中存储的所述指令，执行权利要求1-14中任一所述的方法中在所述基站进行的处理操作。
  16. 一种芯片系统，应用在基站中，其特征在于，包括：所述芯片系统包括至少一个处理器，存储器和接口电路，所述接口电路负责所述芯片系统与外界的信息交互，所述存储器、所述接口电路和所述至少一个处理器通过线路互联，所述至少一个存储器中存储有指令；所述指令被所述至少一个处理器执行，以进行如权利要求1-14中任一所述的方法中在所述基站的操作。
  17. 一种计算机可读存储介质，应用于基站中，其特征在于，所述计算机可读存储介质中存储有指令，当所述指令在计算设备上运行时，以进行如权利要求1-14中任一所述的方法中在所述基站的操作。
  18. 一种通信系统，其特征在于，包括：如权利要求15所述的基站。
  19. 一种计算机程序产品，应用于基站中，其特征在于，所述计算机程序包括一系列指令，当所述指令被运行时，以进行如权利要求1-14中任一所述的方法中在所述基站的操作。
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