Cell reselection method and communication device

Abstract

The invention discloses a cell reselection method and a communication device. The method comprises the following steps: acquiring NSAG information associated with at least one network slice; acquiring NS-AoS information corresponding to the at least one network slice; and performing cell reselection according to the one or more network slices for cell reselection, the NSAG information and the NS-AoS information. According to a traditional cell reselection method, UE does not execute cell reselection according to NS-AoS information, so that a cell which does not support a network slice may be reselected, and the UE cannot initiate a registration request or a service request for the network slice. According to the method, when the UE executes the cell reselection, the cell reselection is executed according to the one or more network slices used for the cell reselection and the NSAG information, and the NS-AoS information corresponding to the network slices is also considered, so that the UE can be prevented from being reselected to cells except the NS-AoS corresponding to the required network slices, and the success rate of requesting network slice services by the UE can be improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of wireless communication technologies, and in particular, to a cell reselection method and a communication device. Background Art

[0002] With the development of mobile communication technologies, various new services and application scenarios have emerged continuously. There are significant differences in the requirements of these services in terms of network functions, connection performance, security, etc. If a single network is used to carry these services, it is difficult to meet the requirements of high bandwidth, low latency, high reliability, etc. at the same time; if a separate network is established for each service, it will bring higher costs. This requires that the communication system be flexible and scalable while meeting different service requirements. Therefore, the 5G communication system provides customized network services for users through end-to-end network slicing. By flexibly allocating network resources and networking on demand, the 5G communication system virtualizes multiple network slices with different characteristics and isolated from each other on the same set of physical facilities to provide services for users specifically.

[0003] Currently, network slices are deployed at the radio access network (RAN) side according to the tracking area (TA) granularity, that is, all cells within a TA support the same network slice. However, in some cases, the network side configuration may be affected, and the granularity of the service area of the network slice may be smaller than the TA. Therefore, the concept of network slice area of service (NS-AoS) is introduced to indicate the current service area of the network slice. The NS-AoS can be represented by the cell identifier (such as the NR cell global identifier NCGI) corresponding to one or more cells.

[0004] However, when the NS-AoS corresponding to the network slice is configured on the network side, how the terminal device realizes cell reselection based on the network slice is a technical problem that needs to be solved currently. Summary of the Invention

[0005] The embodiments of the present application provide a cell reselection method and a communication device, which are used to prevent the terminal device from reselecting to a cell outside the service area range corresponding to the network slice during cell reselection, and help improve the success rate of the terminal device requesting network slice services.

[0006] In a first aspect, an embodiment of the present application provides a cell reselection method applied to a terminal device. The method includes: obtaining network slice access stratum group (NSAG) information associated with at least one network slice; obtaining network slice service area (NS-AoS) information corresponding to at least one network slice; and performing cell reselection according to one or more network slices for cell reselection, the NSAG information, and the NS-AoS information.

[0007] If the terminal device does not perform cell reselection according to the NS-AoS information according to the traditional cell reselection method, the terminal device may reselect to a cell that does not support network slicing, resulting in the terminal device being unable to initiate a registration request or a service request for the network slice. However, according to the method provided in the above embodiment of the present application, when the terminal device needs to perform cell reselection, it not only performs cell reselection according to one or more network slices for cell reselection and the NSAG information, but also performs cell reselection according to the NS-AoS information corresponding to the network slice, which can prevent the terminal device from reselecting to a cell outside the NS-AoS corresponding to the required network slice, thereby helping to improve the success rate of the UE's request for network slice services.

[0008] In a possible implementation manner, the performing cell reselection according to one or more network slices for cell reselection, the NSAG information, and the NS-AoS information includes: the non-access stratum of the terminal device sends one or more network slices for cell reselection, the NSAG information, and first NS-AoS information to the access stratum of the terminal device, where the first NS-AoS information is the obtained NS-AoS information or the NS-AoS information corresponding to one or more network slices for cell reselection in the obtained NS-AoS information; and the access stratum of the terminal device performs cell reselection according to one or more network slices for cell reselection, the NSAG information, and the first NS-AoS information.

[0009] In a possible implementation manner, the performing cell reselection according to one or more network slices for cell reselection, the NSAG information, and the first NS-AoS information includes: sorting the frequency points for cell reselection according to one or more network slices for cell reselection, the NSAG information, and the first NS-AoS information; and determining the reselection resident cell according to the sorted frequency points.

[0010] In a possible implementation, sorting the frequency points for cell reselection includes: sorting the frequency points for cell reselection according to at least one of the following sorting rules: the higher the priority of the NSAG, the higher the priority of the frequency points supporting the NSAG; the larger the service area range corresponding to the NSAG, the higher the priority of the frequency points supporting the NSAG; the larger the service area range corresponding to the NSAG indicates that the number of cells included in the NS-AoS corresponding to the network slice associated with the NSAG is larger.

[0011] In a possible implementation, if at least one network slice associated with the first NSAG for cell reselection does not have corresponding NS-AoS information, and all network slices associated with the second NSAG for cell reselection have corresponding NS-AoS, the service area range corresponding to the first NSAG is larger than the service area range corresponding to the second NSAG; or, if at least one network slice associated with the first NSAG does not have corresponding NS-AoS information, and all network slices associated with the second NSAG have corresponding NS-AoS, the service area range corresponding to the first NSAG is larger than the service area range corresponding to the second NSAG.

[0012] In a possible implementation, the higher the priority of the NSAG, the higher the priority of the frequency points supporting the NSAG, includes: the priority of the frequency points supporting the NSAG is higher than the priority of the frequency points not supporting the NSAG.

[0013] In a possible implementation, the service area range corresponding to the NSAG is determined by taking the union of the NS-AoS corresponding to one or more network slices associated with the NSAG by the access stratum of the terminal device; or, the service area range corresponding to the NSAG is determined by taking the union of the NS-AoS corresponding to one or more network slices associated with the NSAG by the access stratum of the terminal device.

[0014] In a possible implementation, after sorting the frequency points for cell reselection, the method further includes: if the access stratum of the terminal device determines that the first frequency point is the highest-priority frequency point according to the priority of the third NSAG supported by the first frequency point and / or the service area range corresponding to the third NSAG, and the best cell or the highest-ranked cell on the first frequency point is outside the service area range corresponding to the third NSAG, the access stratum of the terminal device determines that the best cell or the highest-ranked cell does not support the third NSAG.

[0015] In a possible implementation, the method further includes: if the best cell or the cell with the highest ranking still supports the fourth NSAG, the access stratum of the terminal device re-orders the first frequency point according to the fourth NSAG information and / or the service area range corresponding to the fourth NSAG.

[0016] In a second aspect, an embodiment of the present application provides a cell reselection method applied to a terminal device. The method includes: obtaining network slice access stratum group (NSAG) information associated with at least one network slice; obtaining network slice area of service (NS-AoS) information corresponding to at least one network slice; performing cell reselection according to a first network slice and / or first NSAG information; the first network slice is a network slice without corresponding NS-AoS information among one or more network slices used for cell reselection; the first NSAG information is NSAG information associated with the first network slice.

[0017] Network slices are deployed in the network side according to TA granularity, but there may be a situation where some cells in the TA do not support the network slice. Therefore, there may be corresponding NS-AoS for some network slices, while some network slices do not have NS-AoS. If the terminal device performs cell reselection based on a network slice with corresponding NS-AoS, it may reselect to a cell outside the NS-AoS corresponding to the network slice supported by the neighboring cell, which may cause the terminal device to be unable to initiate a registration or service request for the network slice, reducing the success rate of the terminal device's request for network slice services. In the above embodiment of the present application, when the terminal device performs cell reselection, it can exclude the network slice with corresponding NS-AoS. Therefore, the cell where the terminal device camps after cell reselection can meet the requirement of initiating a registration or service request for the network slice, which helps to improve the success rate of the terminal device's request for network slice services.

[0018] In a possible implementation, performing cell reselection according to the first network slice and / or the first NSAG information includes: when receiving first indication information, performing cell reselection according to the first network slice and / or the first NSAG information, the first indication information is used to indicate that there is a neighboring cell outside the NS-AoS corresponding to the network slice supported by the neighboring cell.

[0019] In a possible implementation, performing cell reselection according to the first network slice and / or the first NSAG information includes: the non-access stratum of the terminal device determines the first network slice and / or the first NSAG information; the non-access stratum sends the first network slice and / or the first NSAG information to the access stratum of the terminal device; the access stratum performs cell reselection according to the first network slice and / or the first NSAG information.

[0020] In a possible implementation, before the non-access stratum of the terminal device determines the first network slice and / or the first NSAG information, the method further includes: the access stratum receives first indication information, where the first indication information is used to indicate that there is a neighboring cell outside the NS-AoS corresponding to the network slice supported by the neighboring cell; the access stratum sends the first indication information to the non-access stratum; the non-access stratum of the terminal device determines the first network slice and / or the first NSAG information, including: the non-access stratum determines the first network slice and / or the first NSAG information according to the first indication information.

[0021] In a possible implementation, performing cell reselection according to the first network slice and / or the first NSAG information includes: the non-access stratum of the terminal device sends one or more network slices for cell reselection, the NSAG information, and the NS-AoS information to the access stratum of the terminal device; the access stratum determines the first network slice and / or the first NSAG information; the access stratum performs cell reselection according to the first network slice and / or the first NSAG information.

[0022] In a possible implementation, the first indication information further includes: an NSAG identifier associated with a network slice corresponding to the NS-AoS information.

[0023] In a third aspect, an embodiment of the present application provides a cell reselection method applied to a terminal device. The method includes: obtaining cell reselection parameters configured for a frequency point based on a network slice access stratum group (NSAG) that are valid in a specific service area; obtaining NSAG information associated with at least one network slice that is valid in the specific service area, where the NSAG information includes one or more of the following: an association relationship between a network slice and an NSAG identifier, an NSAG priority, an NSAG service area NSAG-AoS information, an identifier of the NSAG-AoS; the NSAG-AoS information is used to indicate one or more cells that support the NSAG; the identifier of the NSAG-AoS is used for the terminal device to distinguish NSAGs with the same NSAG identifier in different NSAG-AoSs; performing cell reselection according to the cell reselection parameters, one or more network slices for cell reselection, and the NSAG information.

[0024] The terminal device performs cell reselection according to the cell reselection parameters configured for the frequency band based on the NSAG valid in a specific service area, one or more network slices for cell reselection, and the NSAG information valid in the specific service area, which can avoid the terminal device reselecting to a cell outside the NS-AoS corresponding to the slice for cell reselection, thereby helping to improve the success rate of the service requested by the terminal device and further enhancing the user experience.

[0025] In a possible implementation manner, the cell reselection parameter further includes an identifier of the NSAG-AoS.

[0026] In a fourth aspect, an embodiment of the present application provides a cell reselection method, which is applied to an access network device. The method includes: obtaining network slice service area NS-AoS information corresponding to network slices supported by a neighboring cell; sending first indication information to a terminal device, where the first indication information is used to indicate that there is a neighboring cell outside the NS-AoS corresponding to the network slices supported by the neighboring cell.

[0027] In a possible implementation manner, the first indication information further includes: sending an NSAG identifier associated with a network slice corresponding to the NS-AoS information to the terminal device.

[0028] In a fifth aspect, an embodiment of the present application provides a cell reselection method, which is applied to a first access network device. The method includes: obtaining information on a network slice access layer group NSAG valid in a specific service area; sending cell reselection parameters configured for a frequency band based on the NSAG valid in the specific service area according to the NSAG information.

[0029] In a possible implementation manner, the cell reselection parameter further includes an identifier of the NSAG service area NSAG-AoS, and the identifier of the NSAG-AoS is used to distinguish and identify NSAGs with the same NSAG identifier in different NSAG-AoS information.

[0030] In a possible implementation manner, the method further includes: sending the identifier of the NSAG-AoS and the NSAG information supported by the NSAG-AoS to a core network device.

[0031] In a possible implementation manner, the method further includes: sending the identifier of the NSAG-AoS and the NSAG information supported by the NSAG-AoS to a second access network device.

[0032] Sixth aspect, an embodiment of the present application provides a cell reselection method applied to a core network device. The method includes: receiving an identifier of a network slice access layer group service area (NSAG-AoS) and NSAG information supported by the NSAG-AoS; sending to a terminal device the NSAG information associated with at least one configured network slice of the terminal device, where the NSAG information includes one or more of the following: the association relationship between a network slice and an NSAG identifier, the NSAG priority, the NSAG service area (NSAG-AoS) information, the identifier of the NSAG-AoS; the NSAG-AoS information is used to indicate one or more cells supporting the NSAG; the identifier of the NSAG-AoS is used for the terminal device to distinguish NSAGs with the same NSAG identifier in different NSAG-AoSs.

[0033] Seventh aspect, an embodiment of the present application provides a communication device. The communication device includes: a processor, the processor is coupled with a memory, and the memory is used to store programs or instructions. When the programs or instructions are executed by the processor, the device executes the methods according to the first aspect and any possible implementation manner of the first aspect, or executes the methods according to the second aspect and any possible implementation manner of the second aspect, or executes the methods according to the third aspect and any possible implementation manner of the third aspect.

[0034] Eighth aspect, an embodiment of the present application provides a communication device. The communication device includes: a processor, the processor is coupled with a memory, and the memory is used to store programs or instructions. When the programs or instructions are executed by the processor, the device executes the methods according to the fourth aspect and any possible implementation manner of the fourth aspect, or executes the methods according to the fifth aspect and any possible implementation manner of the fifth aspect.

[0035] Ninth aspect, an embodiment of the present application provides a communication device. The communication device includes: a processor, the processor is coupled with a memory, and the memory is used to store programs or instructions. When the programs or instructions are executed by the processor, the device executes the methods according to the sixth aspect and any possible implementation manner of the sixth aspect.

[0036] Tenth aspect, an embodiment of the present application provides a chip, including: a processor, the processor is coupled with a memory, and the memory is used to store instructions. When the instructions are executed by the processor, the chip implements the methods described in the first aspect to the sixth aspect and any implementation manner thereof.

[0037] In an eleventh aspect, an embodiment of the present application provides a computer-readable storage medium. The computer-readable storage medium stores instructions, and when the instructions run on a computer, the computer is caused to execute the method described in any one of the first aspect to the sixth aspect and any of its implementation manners.

[0038] In a twelfth aspect, an embodiment of the present application provides a computer program product containing instructions, and when it runs on a computer, the computer is caused to execute the method described in any one of the first aspect to the sixth aspect and any of its implementation manners.

[0039] For the technical effects that can be achieved by any one of the above seventh aspect to twelfth aspect, reference can be made to the corresponding technical effects that can be achieved by any one of the above first aspect to sixth aspect, and repeated parts will not be elaborated. Description of the Drawings

[0040] Figure 1 It is a schematic diagram of network slice deployment provided by an embodiment of the present application;

[0041] Figure 2 It is a schematic diagram of a network architecture provided by an embodiment of the present application;

[0042] Figure 3 It is a schematic flowchart of a cell reselection method provided by an embodiment of the present application;

[0043] Figure 4 It is a schematic flowchart of another cell reselection method provided by an embodiment of the present application;

[0044] Figure 5 It is a schematic flowchart of yet another cell reselection method provided by an embodiment of the present application;

[0045] Figure 6 It is a schematic flowchart of yet another cell reselection method provided by an embodiment of the present application;

[0046] Figure 7 It is a schematic flowchart of yet another cell reselection method provided by an embodiment of the present application;

[0047] Figure 8 It is a schematic diagram of network slice deployment provided by an embodiment of the present application;

[0048] Figure 9 It is a schematic diagram of the structure of a communication device provided by an embodiment of the present application;

[0049] Figure 10 It is a schematic diagram of the structure of another communication device provided by an embodiment of the present application. Detailed Embodiments

[0050] Different network slices can be identified and differentiated by single network slice selection assistance information (S-NSSAI). Each S-NSSAI can include the following information:

[0051] 1. Slice / Service Type (SST), which is used to indicate the characteristics and service types of network slices;

[0052] 2. Slice Differentiator (SD), as a supplement to SST, can further differentiate multiple network slices that meet the same SST. SD is optional information.

[0053] Network Slice Selection Assistance Information (NSSAI) can represent one or more network slices, such as a list of S-NSSAI. Regarding NSSAI, the following multiple types can be included:

[0054] 1. Subscribed NSSAI: Belongs to the subscribed data of the UE.

[0055] 2. Default NSSAI: According to the operator's policy, one or more of the NSSAI subscribed by the UE may be set as the default NSSAI; if the UE does not carry the Allowed NSSAI in the registration request message and the UE has a default NSSAI, the network side can use the network slice corresponding to the default NSSAI to provide services to the UE.

[0056] 3. Requested NSSAI: It is the Allowed NSSAI or Configured NSSAI carried by the UE in the registration request message.

[0057] 4. Allowed NSSAI: It represents one or more S-NSSAI among the NSSAI requested by the UE that are allowed by the network side. The one or more allowed S-NSSAI can be sent to the UE through the "Allowed NSSAI" information element (IE) in the registration accept message; the one or more allowed S-NSSAI can be supported in the UE's registration area (RA).

[0058] 5. Partially allowed NSSAI: Represents one or more S-NSSAIs that are supported within some of the tracking areas (TAs) included in the UE's registration area.

[0059] 6. Configured NSSAI: Represents the NSSAI configured by the network side for the UE to use. The NSSAI configured by the network side can be sent to the UE through the "configured NSSAI" IE in the registration accept message. If the configuration of the UE changes after registration, the network side can notify the UE to update through the configuration update command.

[0060] 7. Rejected NSSAI: Represents that one or more S-NSSAIs in the NSSAI requested by the UE are rejected by the network side. For example, the core network or the access network side does not support the one or more S-NSSAIs.

[0061] 8. Partially rejected NSSAI: Represents one or more S-NSSAIs in the NSSAI requested by the UE that are supported only in some of the TAs in the UE's registration area.

[0062] The network slice list supported by the access network device (i.e., slice list) can be pre-configured by the operation administration and maintenance (OAM) system at the TA granularity, that is, the cells within one TA support the same slices. The access network device can report the above pre-configured network slice list to the core network when establishing the NG interface with the core network; if the access network device can also support the separation of the centralized unit / distributed unit (CU / DU), then the DU can first send the network slice list supported by each TA to the CU, and then the CU reports it to the core network.

[0063] When a UE that has subscribed to a network slice service initiates an initial network access, it can send a registration request for a specific network slice through a Radio Resource Control Setup Complete message carrying the requested NSSAI. This message is transparently transmitted by the access network device (the access network device does not parse the registration request) to the core network. The core network combines the subscribed information of the UE (i.e., the subscribed NSSAI) in the unified data management network element (UDM) to determine whether the network side (including the radio access network and the core network) allows the network slice requested by the UE to provide services to the UE. If the core network confirms that the current network side can support the services corresponding to the requested NSSAI, it returns the allowed NSSAI and the RA range of the UE (the RA range can be represented by a Tracking Area Identity list (TAI list)) to the UE through a Registration Accept message. If the core network confirms that the current network cannot support some or all of the services corresponding to the S-NSSAIs in the requested NSSAI, it will return the allowed NSSAI and / or the rejected NSSAI and the RA range of the UE to the UE through a Registration Accept message. When the UE moves within the RA range, it cannot initiate a new registration request for the rejected NSSAI.

[0064] The access network device can notify the UE of the cell reselection priority for the network slice and specific random access parameters through broadcasting. Specifically, the cell reselection priority for the network slice and specific random access parameters can be included in System Information Block (SIB) 16 and SIB1, respectively. Considering that broadcasting based on the network slice granularity may bring relatively large overhead to the SIB and there are security risks, the concept of a Network Slice Access Stratum Group (NSAG) is proposed, that is, grouping and managing one or more network slices. Specifically, one or more S-NSSAIs assigned to a group are associated with the corresponding NSAG ID, and the association relationship between the NSAG ID and the S-NSSAI is unique within a specific area. The above association relationship has the following specific characteristics:

[0065] 1. Bidirectional association, including the ID value of the NSAG and the related S-NSSAI.

[0066] 2. It is configured by the OAM for the access network device. The access network device sends the association relationship to the core network through the NG interface, and then the core network provides it to the UE through the non-access stratum (NAS) message.

[0067] 3. The granularity of the area validity is TA. When the core network sends the association relationship of the NSAG to the UE through the NAS message, it can carry the TA list (i.e., TAI list) corresponding to the effective TA of the association relationship at the same time.

[0068] 4. It is allowed that a network slice is not associated with any NSAG.

[0069] 5. A network slice can be associated with NSAGs belonging to different purposes, that is, different purposes can each independently have the association relationship between the NSAG and the network slice. For example, network slice 1 (slice#1) can be associated with NSAG#1 for cell reselection and can also be associated with NSAG#2 for random access at the same time; however, for the same purpose, a network slice is not allowed to be associated with multiple NSAGs.

[0070] 6. The corresponding NSAG priority can be configured for each NSAG.

[0071] When an idle or inactive UE needs to perform the cell reselection process based on the NSAG due to mobility, the cell reselection priority needs to be derived based on the following:

[0072] 1. Among the NSAG information provided by the non-access stratum (NAS), the NSAG information associated with one or more network slices provided by the NAS for cell reselection. Currently, after receiving the NSAG information supported within the TA sent by the access network device, the access and mobility management function (AMF) can send the NSAG information associated with the UE's configured NSSAI to the non-access stratum of the UE through the UE's registration process. The UE non-access stratum (i.e., UE NAS) then transparently transmits the above NSAG information to the UE access stratum (access stratum, AS) (i.e., UE AS). In addition, the UE non-access stratum can also send the requested NSSAI, allowed NSSAI, and partially allowed NSSAI to the UE access stratum (i.e., the non-access stratum provides one or more network slices for cell reselection to the access stratum). Then, the UE access stratum can determine the NSAG information for cell reselection based on one or more network slices and NSAG information for cell reselection.

[0073] 2. Slice information in broadcast or RRC dedicated messages. This slice information is defined in SIB16 or RRC release messages, and includes the NSAG ID supported by the frequency points to which the current serving cell and neighboring cells belong, as well as the corresponding frequency points that can be supported and the cell reselection priorities. That is to say, the network side configures cell reselection parameters dedicated to network slices based on the NSAG ID.

[0074] The UE sorts the possible frequency points for cell reselection according to the above content, for use in subsequent measurements during the cell reselection process and the evaluation of the best cell (inter-frequency neighboring cell) / highest ranked cell (intra-frequency neighboring cell).

[0075] Currently, network slices are deployed at the RAN side in tracking area (TA) granularity, that is, all cells within a TA support the same network slice. However, when network slices are deployed within a certain time interval or when a network slice retires from the network, the UE and network configurations may be affected. For example, when a network slice becomes unavailable or available, it may affect the allowed NSSAI and other parameters, and thus the registration area (RA) may also change. Therefore, it is possible that the service area of a network slice does not match the network slice supported by the TA to which the service area belongs, that is, the granularity of the service area is smaller than that of the TA. It can be understood that the minimum granularity of the service area is the cell rather than the TA. For Figure 1 example, TA1 supports network slice 2, and the TA includes 4 cells, namely cell 1, cell 2, cell 3, and cell 4. Due to network deployment and other reasons, the resources allocated to slice 2 in cell 2 are suddenly limited, that is, no resources for slice 2 are configured in cell 2. Therefore, cell 2 actually cannot provide services for the UE for slice 2. In the embodiments of this application, if a cell does not configure resources for a network slice, it can be said that the cell does not support the network slice; if a cell supports a network slice, it means that the cell has configured corresponding resources for the network slice. To avoid affecting the UE and the network side, the concept of network slice area of service (NS-AoS) is introduced to indicate the service area of the network slice. The NS-AoS can be represented by the cell identifiers (such as the NR cell global identifier NCGI) corresponding to one or more cells.

[0076] The NS-AoS is deployed on the RAN side, and the AMF can obtain the NS-AoS corresponding to each network slice within the UE RA through OAM. When the UE indicates support for the single network slice location availability information (S-NSSAI location availability information, which is used to indicate the NS-AoS corresponding to the network slice), the AMF can send the NS-AoS corresponding to the configured NSSAI within the RA to the UE through the registration accept message or the UE configuration update message.

[0077] After the NS-AoS corresponding to different network slices is sent to the UE, the following operations may occur:

[0078] If the NS-AoS received by the UE is the one corresponding to the requested NSSAI, then after the UE initiates a registration request for this network slice outside the NS-AoS, this network slice can be determined by the AMF as the allowed NSSAI or the partially allowed NSSAI.

[0079] If the NS-AoS received by the UE is the one corresponding to the rejected NSSAI or the partially rejected NSSAI, the UE can only initiate a registration request for this network slice in the cells within the NS-AoS corresponding to this network slice.

[0080] If the NS-AoS received by the UE is the one corresponding to the allowed NSSAI or the partially allowed NSSAI, the UE can only activate the user plane of the established PDU session within the NS-AoS corresponding to this network slice.

[0081] When there are cells outside the NS-AoS corresponding to a certain network slice among the neighboring cells of the UE, and the above network slice is one or more slices used by the UE for cell reselection, then when the UE performs cell reselection, it may reselect to a cell outside the NS-AoS corresponding to this network slice based on the NSAG corresponding to this network slice. Since the reselected cell does not configure the corresponding resources for this network slice, the UE cannot initiate a registration or service request for this network slice subsequently, thus reducing the success rate of the UE's request for network slice services (including registration and PDU session user plane activation) and affecting the user experience.

[0082] In view of this, an embodiment of the present application provides a cell reselection method, which helps to prevent a UE from reselecting to a cell outside the NS-AoS corresponding to a network slice during cell reselection, thereby helping to improve the success rate of the UE's request for network slice services.

[0083] The communication method provided by the embodiment of the present application can be applied to a wireless communication system, such as a 5G communication system, a 6G communication system, or other future communication systems. Figure 2 An exemplary schematic diagram of a 5G architecture applicable to the embodiment of the present application is provided. As Figure 2 shown, the network architecture may include a UE, a RAN, a core network, a data network (DN), etc.

[0084] The radio access network (RAN) device is used to implement functions related to wireless access. The radio access network can also be referred to as an access network device or a base station, and is used to connect a terminal to a wireless network. The radio access network can be a base station, an evolved base station (eNodeB) in an LTE system or an evolved LTE system (LTE-advanced, LTE-A), a next generation base station (gNB) in a 5G communication system, a transmission reception point (TRP), a base band unit (BBU), a WiFi access point (AP), a base station in a future mobile communication system, or an access node in a WiFi system, etc. The radio access network can also be a module or unit that completes part of the functions of a base station. For example, it can be a CU, a DU, a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU), etc. The RAN can also be an open radio access network (open RAN, O-RAN or ORAN). In an ORAN system, the CU can also be called an O-CU (open CU), the DU can also be called an O-DU, the CU-CP can also be called an O-CU-CP, the CU-UP can also be called an O-CU-UP, and the RU can also be called an O-RU. The embodiment of the present application does not limit the specific technologies and specific device forms adopted by the radio access network. In the following embodiments, the radio access network is referred to as RAN for illustrative purposes.

[0085] A terminal device is a device with wireless transceiver capabilities. The terminal device is connected to a radio access network device wirelessly, thereby accessing the communication system. The terminal device can also be referred to as a terminal, UE, mobile station, mobile terminal, etc. The terminal device can be a mobile phone, a tablet computer, a computer with wireless transceiver capabilities, a virtual reality (VR) terminal, an augmented reality (AR) terminal, a wireless terminal in industrial control, a whole vehicle, a wireless communication module in a whole vehicle, a telematics box (T-box), a roadside unit (RSU), a terminal device in autonomous driving, a terminal device in the Internet of Things (IoT) network, a terminal device in remote medical, a terminal device in a smart grid, a terminal device in transportation safety, a terminal device in a smart city, or a terminal device in a smart home, etc. The embodiments of this application are not limited thereto. For the convenience of description, the following embodiments of this application will take the UE as an example for illustration.

[0086] The main functions of the core network include providing connections for UEs, managing UEs, and completing bearers for services, and serving as a bearer network to provide an interface to external networks, etc. The core network may include network elements such as an access and mobility management function (AMF), a session management function (SMF), and a user plane function (UPF).

[0087] Among them, the access and mobility management function network element is a control plane network element provided by the operator network, responsible for access control and mobility management of the terminal device accessing the operator network, such as functions including mobile status management, allocating a user temporary identity, authenticating and authorizing users, etc. In 5G, the access and mobility management function network element can be the AMF. In future communication systems, the access and mobility management function network element can still be the AMF, or have other names, which are not limited in this application. For the convenience of description, the following embodiments of this application will take the AMF as an example for illustration.

[0088] It should be understood that Figure 2 is only an example of an applicable network architecture, and the actually applied network architecture may include more or fewer network elements than Figure 1 this.

[0089] Figure 3 The following is a schematic flowchart of a cell reselection method provided by an embodiment of this application. As Figure 3 shown, the method may include the following steps:

[0090] Step 301: The terminal device obtains NSAG information associated with at least one network slice.

[0091] The above at least one network slice belongs to the network slices (configured NSSAI) configured by the terminal device. When the terminal device needs to reselect to a cell that supports a certain network slice, it can perform cell reselection according to the NSAG information associated with the network slice.

[0092] Optionally, the NSAG information associated with the above at least one network slice may be sent by the AMF to the terminal device. For example, after the access network device goes online, it can send the network slices it supports and the NSAG information associated with the network slices to the AMF through the NG interface; the AMF can send the NSAG information associated with the configured NSSAI of the UE to the terminal device through the registration process of the terminal device, so that the terminal device can perform cell reselection according to the obtained NSAG information during the cell reselection process.

[0093] Step 302: The terminal device obtains NS-AoS information corresponding to at least one network slice.

[0094] The above at least one network slice belongs to the configured NSSAI of the terminal device.

[0095] Optionally, the NS-AoS information corresponding to the above at least one network slice may be sent by the AMF to the terminal device. For example, the AMF can obtain the NS-AoS corresponding to each network slice in the UE RA through OAM. When the UE supports the NS-AoS corresponding to the network slice, the AMF can send the NS-AoS corresponding to the configured NSSAI in the RA to the terminal device through a registration accept message or a UE configuration update message.

[0096] Step 303: The terminal device performs cell reselection according to one or more network slices for cell reselection, the obtained NSAG information, and the obtained NS-AoS information.

[0097] In the embodiments of the present application, when a terminal device needs to perform cell reselection, it not only performs cell reselection according to one or more network slices and NSAG information for cell reselection, but also performs cell reselection according to the NS-AoS information corresponding to the network slice, which can prevent the terminal device from reselecting to a cell outside the NS-AoS corresponding to the required network slice, thereby helping to improve the success rate of the UE requesting network slice services. For example, in Figure 1 In the example shown, TA1 supports slice2, but since cell 2 in TA1 does not configure resources for slice2, that is, cell 2 is not in the NS-AoS corresponding to slice2; when the terminal device needs to perform cell reselection and needs to obtain service through slice2, if the terminal device reselects to cell 2, the registration request of the terminal device or the service request based on slice2 will fail. If according to the traditional cell reselection method, the terminal device does not perform cell reselection according to the NS-AoS information, then the terminal device may reselect to cell 2, resulting in the terminal device being unable to initiate a registration request or a service request for slice2; but according to the cell reselection method provided in the embodiments of the present application, the terminal device considers the NS-AoS information corresponding to the network slice during cell reselection, which can prevent the terminal device from reselecting to slice2, thereby helping to improve the success rate of the terminal device requesting network slice services.

[0098] When the terminal device performs step 303 above, it may further perform cell reselection according to one or more network slices for cell reselection, NSAG information, and first NS-AoS information. The first NS-AoS information may be the obtained NS-AoS information, or may also be the NS-AoS information corresponding to one or more network slices for cell reselection respectively.

[0099] For example, the terminal device may implement step 303 in any of the following two ways.

[0100] Method 1: The non-access stratum (NAS) of the terminal device sends one or more network slices for cell reselection, the obtained NSAG information, and the obtained NS-AoS information to the access stratum of the terminal device; the access stratum (AS) of the terminal device performs cell reselection according to one or more network slices for cell reselection, the obtained NSAG information, and the NS-AoS information (i.e., the first NS-AoS information) corresponding to one or more network slices for cell reselection respectively.

[0101] In the above method, the NAS of the terminal device does not process the obtained NS-AoS information and directly sends it to the AS of the terminal device; after receiving the information sent by the NAS of the terminal device, the AS of the terminal device can determine the NS-AoS information (i.e., the first NS-AoS information) corresponding to each of the one or more network slices for cell reselection based on the one or more network slices for cell reselection and the obtained NS-AoS information; then, the AS of the terminal device performs cell reselection based on the one or more network slices for cell reselection, the obtained NSAG information, and the first NS-AoS information.

[0102] Optionally, after receiving the above information sent by the NAS of the terminal device, the AS of the terminal device can also determine the NSAG information associated with each of the one or more network slices for cell reselection based on the one or more network slices for cell reselection and the obtained NSAG information; then the AS of the terminal device can perform cell reselection based on the one or more network slices for cell reselection, the NSAG information associated with each of the one or more network slices for cell reselection, and the first NS-AoS information.

[0103] Method 2: The NAS of the terminal device sends the one or more network slices for cell reselection, the obtained NSAG information, and the first NS-AoS information to the access stratum of the terminal device; the AS of the terminal device performs cell reselection based on the one or more network slices for cell reselection, the obtained NSAG information, and the first NS-AoS information.

[0104] In the above method, the NAS of the terminal device preprocesses the obtained NS-AoS information according to the one or more network slices for cell reselection to obtain the NS-AoS information (i.e., the first NS-AoS information) corresponding to each of the one or more network slices for cell reselection; then the NAS of the terminal device sends the one or more network slices for cell reselection, the obtained NSAG information, and the first NS-AoS information to the AS of the terminal device, so that the AS of the terminal device performs cell reselection according to the above information.

[0105] Optionally, the AS of the terminal device can also determine the NSAG information associated with each of the one or more network slices for cell reselection based on the one or more network slices for cell reselection and the obtained NSAG information; then the AS of the terminal device can perform cell reselection based on the one or more network slices for cell reselection, the NSAG information associated with each of the one or more network slices for cell reselection, and the first NS-AoS information.

[0106] In a possible implementation, when the AS of the terminal device performs cell reselection, it can first sort the frequency points for cell reselection according to one or more network slices, NSAG information, and the first NS-AoS information for cell reselection, and then determine the resident cell for cell reselection according to the sorted frequency bands.

[0107] When the AS of the terminal device sorts the available frequency points, it can sort the frequency points for cell reselection according to at least one of the following sorting rules:

[0108] Rule 1: The higher the NSAG priority, the higher the priority of the frequency point that supports the NSAG.

[0109] For example, the priority of NSAG1 supported by frequency point 1 is 3 (assuming the higher the value, the higher the priority), and the priority of NSAG2 supported by frequency point 2 is 2; because the priority of NSAG1 is higher than the priority of NSAG2, therefore, when sorting frequency point 1 and frequency point 2 according to Rule 1, the priority of frequency point 1 is higher than the priority of frequency point 2.

[0110] Another example, frequency point 1 supports NSAG1 and NSAG2, the priority of NSAG1 is 3, and the priority of NSAG2 is 1; frequency point 2 supports NSAS3 and NSAG4, the priority of NSAG3 is 2, and the priority of NSAG4 is 1. Since frequency point 1 supports NSAG1 and NSAG2, the highest-priority NSAG1 among NSAG1 and NSAG2 can be used as the priority of the NSAG supported by frequency point 1 for comparison with other frequency points; since frequency point 2 supports NSAG3 and NSAG4, the highest-priority NSAG3 among NSAG3 and NSAG4 can be used as the priority of the NSAG supported by frequency point 2 for comparison with other frequency points; therefore, when sorting frequency point 1 and frequency point 2 according to Rule 1, since the priority of NSAG1 is higher than the priority of NSAG3, the priority of frequency point 1 is higher than the priority of frequency point 2.

[0111] Optionally, the NSAG information obtained in step 301 includes the priority of the NSAG, that is, the terminal device can synchronously obtain the NSAG priority in the above step 301. For example, the AMF can send the information of the NSAG associated with the network slice configured by the terminal device (including NSAG identifier, NSAG priority, etc.) to the terminal device. Or, the NSAG priority can also be sent to the terminal device separately from the above NSAG information.

[0112] In a possible implementation, the NSAG priority can be set by a core network element (such as the AMF in the core network); when setting the NSAG priority, the core network element can consider whether there is a corresponding NS-AoS for the network slice associated with the NSAG. For example, if there is a corresponding NS-AoS for the network slice associated with NSAG1, and there is no corresponding NS-AoS for the network slice associated with NSAG2, then the core network element can set the priority of NSAG1 to be lower than the priority of NSAG2.

[0113] Rule 2: The priority of the frequency points supporting NSAG is higher than that of the frequency points not supporting NSAG.

[0114] For example, if frequency point 1 supports NSAG1 and frequency point 2 does not support any NSAG, then the priority of frequency point 1 is higher than that of frequency point 2.

[0115] Rule 2 can be used as an independent rule or as a special case of Rule 1.

[0116] Rule 3: The larger the service area range corresponding to the NSAG, the higher the priority of the frequency points supporting the NSAG.

[0117] Among them, the service area range corresponding to the NSAG represents the number of cells included in the NS-AoS corresponding to the network slice associated with the NSAG, or represents the number of cells included in the NS-AoS corresponding to one or more network slices associated with the NSAG for cell reselection; the larger the number of cells, the larger the service area range. The following are examples of these two cases respectively:

[0118] Case 1: The service area range corresponding to the NSAG represents the number of cells included in the NS-AoS corresponding to the network slice associated with the NSAG.

[0119] For example, NSAG1 is associated with slice1, and the NS-AoS corresponding to slice1 includes 4 cells; NSAG2 is associated with slice2, and the NS-AoS corresponding to slice2 includes 3 cells; then the service area range corresponding to NSAG1 (4 cells) is larger than the service area range corresponding to NSAG2 (3 cells).

[0120] Optionally, when an NSAG is associated with multiple network slices, the union of the NS-AoSs corresponding to the multiple network slices associated with the NSAG can be taken to obtain the service area range corresponding to the NSAG.

[0121] For example, NSAG1 is associated with slice1 and slice2. The NS-AoS corresponding to slice1 includes 4 cells (cell1, cell2, cell3, cell4), and the NS-AoS corresponding to slice2 includes 4 cells (cell1, cell2, cell3, cell5). Taking the union of the NS-AoS corresponding to slice1 and the NS-AoS corresponding to slice2 gives (cell1, cell2, cell3, cell4, cell5). Then, the service area range corresponding to NSAG1 includes 5 cells. NSAG2 is associated with slice3 and slice4. The NS-AoS corresponding to slice3 includes 3 cells (cell1, cell2, cell3), and the NS-AoS corresponding to slice4 includes 4 cells (cell1, cell4, cell5, cell6). Taking the union of the NS-AoS corresponding to slice3 and the NS-AoS corresponding to slice4 gives (cell1, cell2, cell3, cell4, cell5, cell6). Then, the service area range corresponding to NSAG2 includes 6 cells. Therefore, the service area range corresponding to NSAG1 (5 cells) is smaller than the service area range corresponding to NSAG2 (6 cells).

[0122] In a possible example of Rule 3, if there is at least one network slice associated with the first NSAG that does not have corresponding NS-AoS information, and all network slices associated with the second NSAG have corresponding NS-AoS information, then it can be considered that the service area range corresponding to the first NSAG is larger than the service area range corresponding to the second NSAG. If a network slice is not configured with corresponding NS-AoS information by the network side, it can be considered that within the TA supporting this network slice, all cells can provide services for this network slice. In this case, it can be considered that the NS-AoS range corresponding to this network slice is the largest. Therefore, the service area range corresponding to the NSAG associated with this network slice can also be considered the largest.

[0123] Case 2: The service area range corresponding to an NSAG represents the number of cells included in the NS-AoS corresponding to one or more network slices associated with this NSAG for cell reselection.

[0124] For example, if NSAG1 is associated with slice1, the NS-AoS corresponding to slice1 includes 4 cells, and slice1 can be used for cell reselection of the terminal device, then the service area range corresponding to NSAG1 includes 4 cells; if NSAG2 is associated with slice2, the NS-AoS corresponding to slice2 includes 3 cells, and slice2 can be used for cell reselection of the terminal device, then the service area range corresponding to NSAG2 includes 3 cells; then the service area range corresponding to NSAG1 (4 cells) is larger than the service area range corresponding to NSAG2 (3 cells).

[0125] Optionally, when an NSAG is associated with multiple network slices, the union of the NS-AoSs corresponding to one or more network slices associated with the NSAG and used for cell reselection can be taken to obtain the service area range corresponding to the NSAG.

[0126] For example, NSAG1 is associated with slice1, slice2, and slice3. The NS-AoS corresponding to slice1 includes 3 cells (cell1, cell2, cell3), the NS-AoS corresponding to slice2 includes 4 cells (cell1, cell2, cell4, cell5), and the NS-AoS corresponding to slice3 includes 3 cells (cell2, cell3, cell5); among them, slice1 and slice3 can be used for the terminal device to perform cell reselection, then the union of the NS-AoS corresponding to slice1 and the NS-AoS corresponding to slice3 can be taken to obtain (cell1, cell2, cell3, cell5).

[0127] In a possible example of Rule 3, if there is at least one network slice among the network slices associated with the first NSAG and used for cell reselection that has no corresponding NS-AoS information, and all the network slices associated with the second NSAG and used for cell reselection have corresponding NS-AoS information, then it can be considered that the service area range corresponding to the first NSAG is larger than the service area range corresponding to the second NSAG. If a network slice is not configured with corresponding NS-AoS information by the network side, it can be considered that within the TA supporting the network slice, all cells can provide services for the network slice. In this case, it can be considered that the NS-AoS range corresponding to the network slice is the largest. Therefore, when the network slice can be used for cell reselection, the service area range corresponding to the NSAG associated with the network slice can also be considered the largest.

[0128] When a frequency point supports multiple NSAGs, the NSAG with the largest service range among the multiple NSAGs can be used as the basis for sorting the frequency point priorities; among them, the service range of the NSAG can be represented by any one of the representation methods in Case 1 or Case 2. For example, if frequency point 1 supports NSAG1 and NSAG2, where the service area range corresponding to NSAG1 includes 5 cells and the service area range corresponding to NSAG2 includes 6 cells, then when sorting frequency point 1, frequency point 1 can be sorted according to the service area range corresponding to NSAG2; if frequency point 2 supports NSAG1 and NSAG3, where the service area range corresponding to NSAG1 includes 5 cells and the service area range corresponding to NSAG3 includes 4 cells, then when sorting frequency point 2, frequency point 2 can be sorted according to the service area range corresponding to NSAG1; since the service area range corresponding to NSAG2 is larger than the service area range corresponding to NSAG1, then when sorting frequency point 1 and frequency point 2 according to Rule 3, it can be considered that the priority of frequency point 1 is higher than the priority of frequency point 2.

[0129] The above has explained Rules 1, 2, and 3 in detail, but the embodiments of the present application do not limit under what circumstances Rules 1, 2, and 3 are used. For example, Rule 2 can be used to sort the frequency points first, and then Rule 1 can be used to sort multiple frequency points that support NSAGs. If the priorities of the NSAGs supported by multiple frequency points are the same, then Rule 3 can be used to sort these multiple frequency points; for another example, Rule 2 can also be used to sort the frequency points first, and then Rule 3 can be used to sort multiple frequency points that support NSAGs. If the service area ranges corresponding to the NSAGs supported by multiple frequency points are the same, then Rule 1 can be used to sort these multiple frequency points. If the priorities of the NSAGs supported by multiple frequency points are the same and the service area ranges corresponding to the NSAGs are the same, other rules can also be used to sort these multiple frequency points. For example, the frequency points can also be sorted according to the cell reselection priority configured for the NSAG in the cell reselection information; for another example, the frequency points can also be sorted according to the cell reselection priority.

[0130] In a specific embodiment, Rule 2 and Rule 1 can be applied to sort the frequency points first. If the priorities of the NSAGs supported by multiple frequency points are the same, then Rule 3 can be used to sort these multiple frequency points. The following will give a detailed example in combination with Table 1.

[0131] Table 1

[0132]

[0133] When sorting the frequency points according to Rule 2 first, that is, first determining whether each frequency point supports NSAG, the priority of the frequency points that support NSAG is higher than that of the frequency points that do not support NSAG. Then in the specific example shown in Table 1, the frequency point 5 does not support NSAG, so the priority of the frequency point 5 is lower than that of the frequency points 1 to 4.

[0134] Then continue to sort the frequency points 1 to 4 that support NSAG according to Rule 1. The frequency point 1 supports NSAG1 and NSAG2. The priority of NSAG1 is 3, and the priority of NSAG2 is 2. Therefore, the NSAG1 with the highest priority is used as the priority of the NSAG supported by the frequency point 1 for comparison with other frequency points. The frequency point 2 supports NSAG2 and NSAG3. The priority of NSAG2 is 2, and the priority of NSAG3 is 1. Therefore, the NSAG2 with the highest priority is used as the priority of the NSAG supported by the frequency point 2 for comparison with other frequency points. The frequency point 3 supports NSAG4, and the priority of NSAG4 is 2; the frequency point 4 supports NSAG5, and the priority of NSAG5 is also 2. Therefore, the priorities of the NSAGs supported by the frequency points 1, 2, 3, and 4 are 3, 2, 2, and 2 respectively. So the priority of the frequency point 1 is higher than that of the frequency points 2 to 4.

[0135] Since the priorities of the NSAGs supported by the frequency points 2 to 4 are the same, further sort the frequency points 2 to 4 according to Rule 3 and Case 1 in Rule 3.

[0136] The frequency point 2 supports NSAG2 and NSAG3. NSAG2 is associated with slice2, and the NS-AoS corresponding to slice2 includes 4 cells. Then the service area range corresponding to NSAG2 includes 4 cells; NSAG3 is associated with slice3, and the NS-AoS corresponding to slice3 includes 5 cells. Then the service area range corresponding to NSAG3 includes 5 cells; because the service area range corresponding to NSAG3 is larger, the service area range of NSAG3 is used as the service area range of the NSAG supported by the frequency point 2 for comparison with other frequency points.

[0137] The frequency point 3 supports NSAG4. NSAG4 is associated with slice4 and slice5. The NS-AoS corresponding to slice4 includes cell11, cell12, cell13, and the NS-AoS corresponding to slice5 includes cell11, cell13, cell14. Take the union of the NS-AoS corresponding to slice4 and slice5 as cell11, cell12, cell13, cell14. Then the service area range of NSAG4 includes 4 cells.

[0138] Frequency point 4 supports NSAG5. NSAG5 is associated with slice6. The NS-AoS corresponding to slice6 includes 4 cells. Therefore, the service area range of NSAG5 includes 4 cells.

[0139] Since the service area range of the NSAG supported by frequency point 2 includes 5 cells, the service area range of the NSAG supported by frequency point 3 includes 4 cells, and the service area range of the NSAG supported by frequency point 4 includes 4 cells. Therefore, the service area range of the NSAG supported by frequency point 2 is greater than that of the NSAG supported by frequency point 3 and frequency point 4. Therefore, the priority of frequency point 2 is higher than that of frequency point 3 and frequency point 4.

[0140] Since the service area ranges of the NSAGs supported by frequency point 3 and frequency point 4 are the same, frequency point 3 and frequency point 4 can also be sorted according to other information. For example, frequency point 3 and frequency point 4 can be sorted according to the cell reselection priority in the cell reselection information. The above cell reselection priority can be the cell reselection priority in the network slice information (sliceInfo-r17) sent by broadcast, or it can also be the cell reselection priority (nsag-cellreselectionpriority) for the NSAG in the RRC signaling; the higher the cell reselection priority, the higher the priority of the corresponding frequency point. Here, it is assumed that the cell reselection priority configured for frequency point 3 based on NSAG4 is higher than the cell reselection priority configured for frequency point 4 based on NSAG5. Then the priority of frequency point 3 is higher than that of frequency point 4.

[0141] Therefore, the priorities of the above frequency points from high to low are frequency point 1, frequency point 2, frequency point 3, frequency point 4, and frequency point 5.

[0142] In the example shown in Table 1, only frequency point 5 does not support NSAG. If there are multiple frequency points that do not support NSAG, the frequency points that do not support NSAG can also be sorted according to the cell reselection priority in the System Information Block 4 (SIB4). The higher the cell reselection priority of a cell, the higher the priority of the frequency point to which it belongs.

[0143] The above sorting method uses case 1 in rule 3. Case 1 can also be replaced by case 2. That is to say, when the NSAG priorities are the same, the frequency points are sorted according to the service area range of the NSAG supported by the frequency points. Here, the service area range of the NSAG represents the number of cells included in the NS-AoS corresponding to one or more network slices associated with the NSAG for cell reselection. No further examples are given here.

[0144] In another specific embodiment, the frequency points can be sorted by Rule 2 first. For the frequency points that support NSAG, Rule 3 is further used for sorting. If the service area ranges of the NSAG supported by multiple frequency points are also the same, Rule 1 is used to sort these multiple frequency points. Still taking Table 1 as an example below for a detailed illustration.

[0145] First, sort the frequency points according to Rule 2, that is, first determine whether each frequency point supports NSAG. The priority of the frequency points that support NSAG is higher than that of the frequency points that do not support NSAG. Then in the specific example shown in Table 1, the frequency point 5 does not support NSAG, so the priority of the frequency point 5 is lower than that of the frequency points 1 to 4.

[0146] Then continue to sort the frequency points 1 to 4 that support NSAG according to Rule 3.

[0147] The frequency point 1 supports NSAG1 and NSAG2. NSAG1 is associated with slice1, and the NS-AoS corresponding to slice1 includes 4 cells; NSAG2 is associated with slice2, and the NS-AoS corresponding to slice2 includes 4 cells. Then the service area range corresponding to NSAG1 includes 4 cells.

[0148] The frequency point 2 supports NSAG2 and NSAG3. NSAG2 is associated with slice2, and the NS-AoS corresponding to slice2 includes 4 cells, so the service area range corresponding to NSAG2 includes 4 cells; NSAG3 is associated with slice3, and the NS-AoS corresponding to slice3 includes 5 cells, so the service area range corresponding to NSAG3 includes 5 cells; because the service area range corresponding to NSAG3 is larger, the service area range of NSAG3 is used as the service area range of the NSAG supported by the frequency point 2 for comparison with other frequency points.

[0149] The frequency point 3 supports NSAG4. NSAG4 is associated with slice4 and slice5. The NS-AoS corresponding to slice4 includes cell11, cell12, cell13, and the NS-AoS corresponding to slice5 includes cell11, cell13, cell14. Take the union of the NS-AoS corresponding to slice4 and slice5 as cell11, cell12, cell13, cell14. Then the service area range of NSAG4 includes 4 cells.

[0150] The frequency point 4 supports NSAG5. NSAG5 is associated with slice6, and the NS-AoS corresponding to slice6 includes 4 cells. Then the service area range of NSAG5 includes 4 cells.

[0151] It can be seen that among frequency points 1 to 4, the service area range of NSAG3 supported by frequency point 2 is the largest. Therefore, the priority of frequency point 2 is higher than that of frequency points 1, 3, and 4. The service area ranges of NSAG supported by frequency points 1, 3, and 4 all include 4 cells. Therefore, it is necessary to further sort frequency points 1, 3, and 4.

[0152] Optionally, frequency points 1, 3, and 4 can be sorted according to Rule 1. Frequency point 1 supports NSAG1 and NSAG2. The priority of NSAG1 is 3, and the priority of NSAG2 is 2. Therefore, the NSAG with the highest priority, NSAG1, is used as the priority of the NSAG supported by frequency point 1 for comparison with other frequency points. Frequency point 3 supports NSAG4, and the priority of NSAG4 is 2; frequency point 4 supports NSAG5, and the priority of NSAG5 is also 2. Therefore, the priorities of NSAG supported by frequency points 1, 3, and 4 are 3, 2, and 2 respectively. Therefore, the priority of frequency point 1 is higher than that of frequency points 3 and 4.

[0153] Since the service area ranges of NSAG supported by frequency points 3 and 4 are the same and the NSAG priorities are also the same, frequency points 3 and 4 can also be sorted according to other information. For example, frequency points 3 and 4 can be sorted according to the cell reselection priority in the cell reselection information. The above cell reselection priority can be the cell reselection priority in the network slice information (sliceInfo-r17) sent by broadcast, or it can also be the cell reselection priority (nsag-cellreselectionpriority) for NSAG in the radio resource control (RRC) signaling; the higher the cell reselection priority, the higher the priority of the corresponding frequency point. Assume that the cell reselection priority configured for frequency point 3 based on NSAG4 is higher than the cell reselection priority configured for frequency point 4 based on NSAG5. Then the priority of frequency point 3 is higher than the priority of frequency point 4.

[0154] Therefore, the priorities of the above frequency points from high to low are frequency point 2, frequency point 1, frequency point 3, frequency point 4, and frequency point 5.

[0155] The above sorting method uses Case 1 in Rule 3, and Case 1 can also be replaced by Case 2. That is, the frequency points are sorted according to the service area range of the NSAG supported by the frequency points, where the service area range of the NSAG represents the number of cells included in the NS-AoS corresponding to one or more network slices associated with the NSAG for cell reselection. No further examples are given here.

[0156] After the terminal device sorts the frequency points for cell reselection, it can measure the signal quality of the cells on one or more frequency points with higher priorities, and determine the best cell (heterogeneous frequency neighboring cell) or the highest ranked cell (homogeneous frequency neighboring cell) on the frequency point. If the determined best cell or highest ranked cell is outside the service area range corresponding to the NSAG supported by the frequency point, it is considered that the best cell or highest ranked cell does not support the NSAG.

[0157] Still taking Table 1 as an example, since the priority of NSAG1 is the highest, when sorting according to Rule 1, the priority of frequency point 1 is the highest. The cells on frequency point 1 include cell1, cell2, cell3, cell4, cell5. After measurement, if cell5 is the best cell or the highest ranked cell, but since cell5 is outside the service area range corresponding to NSAG1 (because NSAG1 is associated with slice1 and cell5 is outside the NS-AoS corresponding to slice1), then cell5 does not support NSAG1.

[0158] Since cell5 does not support NSAG1, if the terminal device reselects the cell to cell5, it may cause the registration request or service request based on NSAG1 to fail. Therefore, in order to improve the success rate of the UE's request for network slice services, the terminal device can be prevented from reselecting the cell to cell5.

[0159] A possible implementation method is to use the second ranked cell evaluated according to the frequency point sorting as the best cell or the highest ranked cell. Suppose the neighboring cell rankings from high to low after evaluation are cell5, cell1, cell3, cell2, cell4, then cell1 can be used as the best cell or the highest ranked cell.

[0160] Another possible implementation method is that although cell5 does not support NSAG1, it can support NSAG2. Then, the frequency point 1 can be sorted again according to the priority of NSAG2 and / or the service area range corresponding to NSAG2.

[0161] To prevent the UE from reselecting to a cell outside the NS-AoS corresponding to the network slice during cell reselection, the embodiment of the present application also provides a cell reselection method, which helps to improve the success rate of the UE's request for network slice services.

[0162] Figure 4 The following is a schematic flowchart of a cell reselection method provided by the embodiment of the present application, as Figure 4 shown. The method may include the following steps:

[0163] Step 401, the terminal device obtains NSAG information associated with at least one network slice.

[0164] At least one of the above network slices belongs to the network slices configured by the terminal device (configured NSSAI). When the terminal device needs to reselect to a cell supporting a certain network slice, it can perform cell reselection according to the NSAG information associated with the network slice.

[0165] Optionally, the NSAG information associated with at least one of the above network slices may be sent by the AMF to the terminal device. For example, after the access network device goes online, it can send the network slices it supports and the NSAG information associated with the network slices to the AMF through the NG interface; the AMF can send the NSAG information associated with the configured NSSAI of the UE to the terminal device through the registration process of the terminal device, so that the terminal device can perform cell reselection according to the obtained NSAG information during the cell reselection process.

[0166] Step 402: The terminal device obtains the NS-AoS information corresponding to at least one network slice.

[0167] At least one of the above network slices belongs to the configured NSSAI of the terminal device.

[0168] Optionally, the NS-AoS information corresponding to at least one of the above network slices may be sent by the AMF to the terminal device. For example, the AMF can obtain the NS-AoS corresponding to each network slice in the UE RA through OAM. When the UE supports the NS-AoS corresponding to the network slice, the AMF can send the NS-AoS corresponding to the configured NSSAI in the RA to the terminal device through a registration accept message or a UE configuration update message.

[0169] Step 403: The terminal device performs cell reselection according to the first network slice and / or the first NSAG information.

[0170] Among them, the first network slice is a network slice without corresponding NS-AoS information among one or more network slices used for cell reselection. For example, the network slices used by the terminal device for cell reselection include slice1, slice2, and slice3, and the terminal device obtains the NS-AoS corresponding to slice2, then the terminal device determines that the first network slice includes slice1 and slice3.

[0171] The first NSAG information is the NSAG information associated with the first network slice. For example, the network slices used by the terminal device for cell reselection include slice1, slice2, and slice3, and the terminal device obtains the NS-AoS corresponding to slice2, then the terminal device determines that the first NSAG information includes the NSAG information associated with slice1 and the NSAG information associated with slice3.

[0172] As mentioned above, network slices are deployed at the TA granularity on the RAN side, but some cells in the TA may not be able to support the network slice, so some network slices may have corresponding NS-AoS, while some network slices do not have NS-AoS. If the terminal device reselects a cell based on a network slice with a corresponding NS-AoS, it may reselect to a cell outside the NS-AoS corresponding to the network slice, which may cause the terminal device to be unable to initiate registration or service requests for the network slice, reducing the success rate of the terminal device requesting network slice services.

[0173] In the above embodiment of the present application, when the terminal device performs cell reselection, it can eliminate the network slice corresponding to the NS-AoS. Therefore, the cell where the terminal device resides after the cell reselection can satisfy the registration or service request for the network slice, thereby helping to improve the success rate of the terminal device requesting the network slice service.

[0174] In a possible implementation, the terminal device may perform the above step 403 when receiving the first indication information. The terminal device may also perform cell reselection based on the network slice corresponding to the NS-AoS, but after receiving the first indication information, the cell reselection is no longer performed based on the network slice corresponding to the NS-AoS, but the cell reselection is performed according to the first network slice and / or the first NSAG information. Since the first network slice does not include the network slice corresponding to the NS-AoS, the first NSAG information does not include the NSAG information associated with the network slice corresponding to the NS-AoS. Therefore, performing cell reselection based on the first network slice and / or the first NSAG information can prevent the terminal device from reselecting to a cell outside the NS-AoS corresponding to the network slice when reselecting the cell.

[0175] Optionally, the first indication information may be sent by the access network device to the terminal device.

[0176] Optionally, the above first indication information may further include the NSAG identifier associated with the network slice corresponding to the NS-AoS information. The NSAG identifier is used to uniquely identify the NSAG within a certain range (such as within a TA) or globally (such as within a public land mobile network). Since the same NSAG may have different representations in different cells, in order for the terminal device to determine whether the NSAGs represented by different representations in different cells are the same NSAG, the first indication information may include the identifier of the NSAG, such as the NSAG ID, so that the terminal device can identify the NSAGs supported by different cells.

[0177] When the above NSAG identifier is included in the first indication information, the UE may not exclude all the NSAG information associated with the network slices configured with NS-AoS. According to the indication of the access network device, when performing cell reselection in the serving cell, the NSAG identifier associated with the network slice that has not been allocated resources in the neighboring cell can be accurately excluded.

[0178] When the terminal device performs the above step 403, it can be implemented through any one of the following two interaction methods:

[0179] Interaction method 1: The NAS of the terminal device determines the first network slice and / or the first NSAG information, and then sends the determined first network slice and / or the first NSAG information to the AS of the terminal device; the AS of the terminal device performs cell reselection according to the first network slice and / or the first NSAG information.

[0180] In the above method, the NAS of the terminal device preprocesses the network slices for cell reselection according to the obtained NS-AoS information to obtain the first network slice, that is, excludes the network slices with corresponding NS-AoS from one or more network slices for cell reselection; and / or, the NAS of the terminal device preprocesses the obtained NSAG information according to the obtained NS-AoS information to obtain the first NSAG information, that is, excludes the NSAG information associated with the network slices with corresponding NS-AoS from the obtained NSAG information. Then, the NAS of the terminal device sends the first network slice and the first NSAG information to the AS of the terminal device, or sends the first network slice and the obtained NSAG information to the AS of the terminal device, or sends one or more network slices for cell reselection and the first NSAG information to the AS of the terminal device. The terminal device AS performs cell reselection according to the first network slice and the first NSAG information, or performs cell reselection according to the first network slice and the obtained NSAG information, or performs cell reselection according to one or more network slices for cell reselection and the first NSAG information.

[0181] Optionally, if the terminal device performs cell reselection according to the first network slice and / or the first NSAG information only when it receives the first indication information, then after the AS of the terminal device receives the first indication information, it may send the first indication information to the NAS of the terminal device. The NAS of the terminal device determines the first network slice and / or the first NSAG information according to the indication of the first indication information, and then sends it to the AS of the terminal device.

[0182] If the first indication information further includes the NSAG identifier associated with the network slice corresponding to the NS-AoS information, then the first NSAG information sent by the NAS of the terminal device to the AS of the terminal device may also be the NSAG information obtained by the NAS of the terminal device after removing the NSAG information corresponding to the NSAG identifier included in the first indication information from the obtained NSAG information.

[0183] Interaction method 2: The NAS of the terminal device sends one or more network slices for cell reselection, the obtained NSAG information, and the obtained NS-AoS information to the AS of the terminal device; then, the AS of the terminal device determines the first network slice and / or the first NSAG information; finally, the AS of the terminal device performs cell reselection according to the first network slice and / or the first NSAG information.

[0184] In the above method, the NAS of the terminal device does not process one or more network slices for cell reselection, nor does it process the obtained NSAG information, and directly sends it to the AS of the terminal device. The AS of the terminal device may preprocess the network slices for cell reselection according to the obtained NS-AoS information to obtain the first network slice, that is, remove the network slices with corresponding NS-AoS from one or more network slices for cell reselection; and / or, the AS of the terminal device may preprocess the obtained NSAG information according to the obtained NS-AoS information to obtain the first NSAG information, that is, remove the NSAG information associated with the network slices with corresponding NS-AoS from the obtained NSAG information. The AS of the terminal device performs cell reselection according to the first network slice and the first NSAG information, or performs cell reselection according to the first network slice and the obtained NSAG information, or performs cell reselection according to one or more network slices for cell reselection and the first NSAG information.

[0185] Optionally, if the terminal device performs cell reselection based on the first network slice and / or the first NSAG information only when receiving the first indication information, then after the AS of the terminal device receives the first indication information, it processes one or more network slices for cell reselection sent by the NAS of the terminal device and / or the obtained NSAG information to obtain the first network slice and / or the first NSAG information, and then performs cell reselection based on the obtained first network slice and / or the first NSAG information.

[0186] If the first indication information further includes the NSAG identifier associated with the network slice corresponding to the NS-AoS information, then the first NSAG information determined by the AS of the terminal device may also be the NSAG information obtained by removing the NSAG information corresponding to the NSAG identifier included in the first indication information from the received NSAG information.

[0187] To more clearly understand the above embodiments of the present application, the following is combined with Figure 5 、 Figure 6 for illustrative purposes.

[0188] In Figure 5 the specific embodiment shown, the cell reselection method provided by the embodiment of the present application may include the following steps:

[0189] Step 501, the base station sends the first indication information to the UE.

[0190] The above base station is the serving base station of the terminal device. The first indication information may be used to indicate that there is a neighboring cell outside the NS-AoS of the network slice supported by the cell.

[0191] Optionally, the base station may obtain the NS-AoS information corresponding to the network slice supported by the neighboring cell based on the Xn interface from the neighboring station, or the base station may also obtain the NS-AoS information corresponding to the network slice supported by the neighboring cell from the OAM.

[0192] Step 502, the UE AS forwards the first indication information to the UE NAS.

[0193] Optionally, the UE AS may forward the first indication information to the UE NAS when determining that the UE NAS supports the single network slice location availability information (S-NSSAIlocation availability information).

[0194] Step 503, the UE NAS determines the first network slice and / or the first NSAG information according to the NS-AoS information corresponding to the network slice sent by the AMF, the NSAG information associated with the network slice, and one or more network slices for cell reselection.

[0195] Among them, the first network slice is a network slice without corresponding NS-AoS information among one or more network slices for cell reselection. The first NSAG information is the NSAG information associated with the first network slice.

[0196] Optionally, the UE NAS may also only determine the first network slice, or only determine the first NSAG information.

[0197] Step 504: The UE NAS sends the first network slice and / or the first NSAG information to the UE AS.

[0198] Optionally, if the UE NAS only determines the first network slice, it sends the first network slice and the received NSAG information to the UE AS; if the UE NAS only determines the first NSAG information, it sends one or more network slices for cell reselection and the first NSAG information to the UE AS.

[0199] Step 505: When cell reselection needs to be performed, the UE AS performs cell reselection according to the first network slice and / or the first NSAG information.

[0200] Optionally, if the UE NAS sends the first network slice and the received NSAG information to the UE AS, then the UE AS may perform cell reselection according to the first network slice and the received NSAG information. Optionally, the UE AS may also determine the first NSAG information according to the first network slice and the received NSAG information, and then perform cell reselection according to the first network slice and the first NSAG information.

[0201] Optionally, if the UE NAS sends one or more network slices for cell reselection and the first NSAG information to the UE AS, then the UE AS may perform cell reselection according to one or more network slices for cell reselection and the first NSAG information.

[0202] In Figure 6 In the specific embodiment shown, the cell reselection method provided by the embodiment of the present application may include the following steps:

[0203] Step 601: The base station sends first indication information to the terminal device.

[0204] This first indication information may be used to indicate that there is a neighboring cell outside the NS-AoS corresponding to the network slice supported by the neighboring cell.

[0205] Optionally, the base station may obtain the NS-AoS information corresponding to the network slices supported by the neighboring cells from the neighboring station based on the Xn interface. Alternatively, the base station may also obtain the NS-AoS information corresponding to the network slices supported by the neighboring cells from the OAM.

[0206] Step 602: The UE NAS sends one or more network slices for cell reselection, the NS-AoS information corresponding to the network slices, and the NSAG information associated with the network slices to the UE AS.

[0207] Optionally, the NS-AoS information corresponding to the network slices and the NSAG information associated with the network slices may be obtained from the AMF.

[0208] Step 603: The UE AS determines the first network slice and / or the first NSAG information based on the first indication information, one or more network slices for cell reselection, the NS-AoS information corresponding to the network slices, and the NSAG information associated with the network slices.

[0209] If the UE AS determines that it is necessary to determine the first network slice and / or the first NSAG information according to the first indication information, then after receiving the above information sent by the UE NAS, the UE AS determines the first network slice based on one or more network slices for cell reselection and the NS-AoS information corresponding to the network slices, and / or determines the first NSAG information based on one or more network slices for cell reselection, the NS-AoS information corresponding to the network slices, and the NSAG information associated with the network slices. Among them, the first network slice is the network slice without corresponding NS-AoS information among one or more network slices for cell reselection. The first NSAG information is the NSAG information associated with the first network slice.

[0210] Optionally, the UE AS may also only determine the first network slice, or only determine the first NSAG information.

[0211] Step 604: When cell reselection needs to be performed, the UE AS performs cell reselection based on the first network slice and / or the first NSAG information.

[0212] Optionally, if the UE AS determines the first network slice and does not determine the first NSAG information, then the UE AS may perform cell reselection based on the first network slice and the received NS-AoS information.

[0213] Optionally, if the UE AS determines the first NSAG information and does not determine the first network slice, then the UE AS may perform cell reselection based on one or more network slices for cell reselection and the first NSAG information.

[0214] To avoid the UE from reselecting to a cell that does not support the required network slice during cell reselection, the embodiment of the present application further provides a cell reselection method, which helps to improve the success rate of the UE's request for network slice services.

[0215] Figure 7 The following is a schematic flow diagram of a cell reselection method provided by an embodiment of the present application. As Figure 7 shown, the method may include the following steps:

[0216] Step 701, the terminal device obtains cell reselection parameters configured for a frequency point based on the NSAG valid in a specific service area.

[0217] In the embodiment of the present application, the concept of NSAG-AoS is introduced. The traditional concept of AoS is for network slices (NS), that is, NS-AoS. Based on NS-AoS, the concept of NSAG-AoS is proposed in this embodiment, which represents the service area of NSAG. All cells in the service area have available resources for the network slice associated with NSAG.

[0218] Optionally, the network slice used for cell reselection in the same NSAG-AoS can be associated with only one NSAG.

[0219] Optionally, NSAG-AoS can be obtained by taking the intersection of NS-AoS corresponding to one or more network slices associated with NSAG.

[0220] Optionally, the above NSAG information can be configured by OAM and sent to the access network device.

[0221] Optionally, the access network device can also send the NSAG-AoS identifier and the NSAG information supported by NSAG-AoS to other access network devices.

[0222] The cell reselection parameters configured for the frequency point based on NSAG can be indicated to the terminal device by the access network device through broadcast (such as SIB16 or a new SIB) or RRC dedicated information; the cell reselection parameters configured for the frequency point based on NSAG may include NSAG frequency pair information. Optionally, it may further include the identifier of NSAG-AoS (NSAG-AoS ID), which is used for the terminal device to distinguish NSAGs with the same NSAG identifier in different NSAG-AoSs. This information can be as shown in Table 2.

[0223] Table 2

[0224]

[0225] In the specific example shown in Table 2, frequency point 1 supports NSAG1 and NSAG2. The service areas corresponding to NSAG1 include NSAG-AoS1 and NSAG-AoS2, that is, NSAGs with NSAG ID of NSAG1 are configured in both NSAG-AoS1 and NSAG-AoS2. However, the network slices associated with these two NSAGs are not necessarily exactly the same. Then, based on NSAG1 that is valid within NSAG-AoS1, the cell reselection priority configured for frequency point 1 is cell reselection priority a, and based on NSAG1 that is valid within NSAG-AoS2, the cell reselection priority configured for frequency point 1 is cell reselection priority b. The service area corresponding to NSAG2 includes NSAG-AoS3. Then, based on NSAG2 that is valid within NSAG-AoS3, the cell reselection priority configured for frequency point 1 is cell reselection priority c.

[0226] Frequency point 2 supports NSAG3. The service area corresponding to NSAG3 includes NSAG-AoS4. Then, based on NSAG3 that is valid within NSAG-AoS4, the cell reselection priority configured for frequency point 1 is cell reselection priority d. Optionally, the identifier of the TA can be used as a special case of the NSAG-AoS identifier, that is, all cells within the TA are included in the NSAG-AoS. For example, in this implementation, all cells within TA3 are included in NSAG-AoS4, so NSAG-AoS4 can also be represented by TA3.

[0227] Step 702: The terminal device obtains NSAG information associated with at least one network slice within a specific service area.

[0228] Optionally, the above NSAG information that is valid within the specific service area can be configured by the OAM and sent to each access network device. The access network device can send the obtained NSAG information to a core network element (such as the AMF in the core network), and the core network element sends it to the terminal device.

[0229] Optionally, the access network device can also send the NSAG-AoS identifier to the core network element. The NSAG-AoS identifier is used to distinguish and identify NSAGs with the same NSAG identifier in different NSAG-AoS information.

[0230] After the terminal device initiates registration with the core network element, the core network element may send the above NSAG information that is valid within a specific service area to the terminal device when it determines that the terminal device supports NSAG and supports single network slice location availability information (S-NSSAI location availability information); alternatively, the core network element may also send the above NSAG information that is valid within a specific service area to the terminal device when it determines that the terminal device supports NSAG.

[0231] Step 703: The terminal device performs cell reselection based on the cell reselection parameters, one or more network slices for cell reselection, and the obtained NSAG information.

[0232] The terminal device performs cell reselection based on the cell reselection parameters configured for a frequency point based on NSAG, one or more network slices for cell reselection, and the NSAG information that is valid within a specific service area, which can prevent the terminal device from reselecting to a cell outside the NS-AoS corresponding to the slice for cell reselection, thereby helping to improve the success rate of the terminal device's requested services and further enhancing the user experience.

[0233] To more clearly understand the concept of NSAG-AoS proposed in the above embodiments of the present application, the following will be combined with Figure 8 and Table 3 for an illustrative example.

[0234] In Figure 8 the specific embodiment shown, cell1 supports slice1, slice2, slice3, and slice4, cell2 supports slice1 and slice4, cell3 supports slice2, slice3, and slice4, cell4 supports slice1, slice3, and slice4, and cell5 supports slice4 and slice5. Then, the NSAG can be configured based on NSAG-AoS as shown in Table 3.

[0235] Table 3

[0236] NSAG Associated network slice NSAG-AoS NSAG1 slice1, slice4 cell1, cell2, cell4 NSAG2 slice2, slice3 cell1, cell3 NSAG3 slice3, slice4 cell1, cell3, cell4 NSAG4 slice4, slice5 cell5

[0237] As shown in Table 3, NSAG1 is associated with slice1 and slice4. Then, the NSAG-AoS corresponding to NSAG1 is the intersection of the NS-AoS corresponding to slice1 and the NS-AoS corresponding to slice4, that is, taking the intersection of {cell1, cell2, cell4} and {cell1, cell2, cell3, cell4, cell5}, so as to obtain {cell1, cell2, cell4}. Similarly, NSAG2 is associated with slice2 and slice3. Then, the NSAG-AoS corresponding to NSAG2 is the intersection of the NS-AoS corresponding to slice2 and the NS-AoS corresponding to slice3, that is, taking the intersection of {cell1, cell3} and {cell1, cell3, cell4}, so as to obtain {cell1, cell3}. NSAG3 is associated with slice3 and slice4. Then, the NSAG-AoS corresponding to NSAG3 is the intersection of the NS-AoS corresponding to slice3 and the NS-AoS corresponding to slice4, that is, taking the intersection of {cell1, cell3, cell4} and {cell1, cell2, cell3, cell4, cell5}, so as to obtain {cell1, cell3, cell4}. NSAG4 is associated with slice4 and slice5. Then, the NSAG-AoS corresponding to NSAG3 is the intersection of the NS-AoS corresponding to slice4 and the NS-AoS corresponding to slice5, that is, taking the intersection of {cell1, cell2, cell3, cell4, cell5} and {cell5}, so as to obtain {cell5}.

[0238] Figure 9 It is a schematic diagram of a communication device provided according to an embodiment of the present application. The communication device includes a processing module 901 and a transceiver module 902. The processing module 901 is used to implement the processing of data by the communication device. The transceiver module 902 is used to receive the content between the communication device and other units or network elements, or send the content between the communication device and other units or network elements. It should be understood that the processing module 901 in the embodiment of the present application can be implemented by a processor or processor-related circuit components (or, referred to as processing circuitry), and the transceiver module 902 can be implemented by a receiver / transmitter or receiver / transmitter-related circuit components.

[0239] Exemplarily, the communication device can be a communication device, or a chip applied to the communication device, or other combined devices, components, etc. with the functions of the above communication device.

[0240] When the communication device is a terminal device, the processing module 901 determines and obtains network slice access layer group (NSAG) information associated with at least one network slice through the transceiver module 902; obtains network slice service area (NS-AoS) information corresponding to at least one network slice through the transceiver module 902; and performs cell reselection according to one or more network slices for cell reselection, the NSAG information, and the NS-AoS information.

[0241] In addition, each of the above modules may also be used to support Figure 3 other processes performed by the terminal device in the illustrated embodiments. The beneficial effects can be referred to the previous description and will not be elaborated here.

[0242] When the communication device is a terminal device, the processing module 901 obtains network slice access layer group (NSAG) information associated with at least one network slice through the transceiver module 902; obtains network slice service area (NS-AoS) information corresponding to at least one network slice through the transceiver module 902; performs cell reselection according to a first network slice and / or first NSAG information; the first network slice is a network slice without corresponding NS-AoS information among one or more network slices for cell reselection; the first NSAG information is the NSAG information associated with the first network slice.

[0243] In addition, each of the above modules may also be used to support Figures 4 to 6 other processes performed by the terminal device in the illustrated embodiments. The beneficial effects can be referred to the previous description and will not be elaborated here.

[0244] When the communication device is a terminal device, the processing module 901 obtains cell reselection parameters configured for a frequency point based on a network slice access layer group (NSAG) that is valid in a specific service area through the transceiver module 902; obtains NSAG information associated with at least one network slice that is valid in the specific service area through the transceiver module 902, where the NSAG information includes one or more of the following: the association relationship between a network slice and an NSAG identifier, the NSAG priority, the NSAG service area (NSAG-AoS) information, the identifier of the NSAG-AoS; the NSAG-AoS information is used to indicate one or more cells that support the NSAG; the identifier of the NSAG-AoS is used by the terminal device to distinguish NSAGs with the same NSAG identifier in different NSAG-AoSs; and performs cell reselection according to the cell reselection parameters, one or more network slices for cell reselection, and the NSAG information.

[0245] In addition, each of the above modules may also be used to support Figure 7 、 Figure 8 other processes performed by the terminal device in the illustrated embodiments. The beneficial effects can be referred to the previous description and will not be elaborated here.

[0246] When the communication device is an access network device, the processing module 901 obtains the network slice service area NS-AoS information corresponding to the network slices supported by neighboring cells; and sends a first indication message to the terminal device through the transceiver module 902, where the first indication message is used to indicate that there is a neighboring cell outside the NS-AoS of the network slices supported by the neighboring cell.

[0247] In addition, each of the above modules can also be used to support Figures 4 to 6 other processes performed by the access network device in the illustrated embodiments. The beneficial effects can be referred to the previous description and will not be elaborated here.

[0248] When the communication device is an access network device, the processing module 901 obtains the information of the network slice access layer group NSAG that is valid in a specific service area; and sends, according to the NSAG information, cell reselection parameters configured for a frequency point through the transceiver module 902 based on the NSAG that is valid in the specific service area.

[0249] In addition, each of the above modules can also be used to support Figure 7 、 Figure 8 other processes performed by the access network device in the illustrated embodiments. The beneficial effects can be referred to the previous description and will not be elaborated here.

[0250] When the communication device is a core network device, the processing module 901 receives, through the transceiver module 902, the identifier of the network slice access layer group service area NSAG-AoS and the NSAG information supported by the NSAG-AoS; and sends, through the transceiver module 902, the NSAG information associated with at least one configured network slice of the terminal device to the terminal device, where the NSAG information includes one or more of the following: the association relationship between the network slice and the NSAG identifier, the NSAG priority, the NSAG service area NSAG-AoS information, the identifier of the NSAG-AoS; the NSAG-AoS information is used to indicate one or more cells that support the NSAG; and the identifier of the NSAG-AoS is used for the terminal device to distinguish NSAGs with the same NSAG identifier in different NSAG-AoSs.

[0251] In addition, each of the above modules can also be used to support Figure 7 、 Figure 8 other processes performed by the core network device in the illustrated embodiments. The beneficial effects can be referred to the previous description and will not be elaborated here.

[0252] Figure 10Schematic diagram of another communication device provided according to an embodiment of the present application. The communication device includes: a processor 1001, a communication interface 1002, and further may include a memory 1003 and a bus 1004. Among them, the processor 1001, the communication interface 1002, and the memory 1003 can be interconnected through the bus 1004; the bus 1004 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The above-mentioned bus 1004 can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 10 only one line is used to represent it in the figure, but it does not mean that there is only one bus or one type of bus.

[0253] The processor 1001 can be a central processing unit (CPU), a network processor (NP), or a combination of a CPU and an NP. The processor may further include a hardware chip. The above-mentioned hardware chip can be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The above-mentioned PLD can be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof. The memory 1003 can be a volatile memory or a non-volatile memory, or may include both a volatile memory and a non-volatile memory. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable ROM (PROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache.

[0254] Among them, the processor 1001 is used to implement the data processing operations of the communication device, and the communication interface 1002 is used to implement the receiving and sending operations of the communication device.

[0255] When the communication device is a terminal device, the processor 1001 obtains the network slice access layer group NSAG information associated with at least one network slice through the communication interface 1002; obtains the network slice service area NS-AoS information corresponding to at least one network slice through the communication interface 1002; and performs cell reselection according to one or more network slices for cell reselection, the NSAG information, and the NS-AoS information.

[0256] In addition, the above components can also be used to support Figure 3 other processes performed by the terminal device in the illustrated embodiments. The beneficial effects can be referred to the previous description and will not be elaborated here.

[0257] When the communication device is a terminal device, the processor 1001 obtains the network slice access layer group NSAG information associated with at least one network slice through the communication interface 1002; obtains the network slice service area NS-AoS information corresponding to at least one network slice through the communication interface 1002; performs cell reselection according to the first network slice and / or the first NSAG information; the first network slice is a network slice without corresponding NS-AoS information among one or more network slices for cell reselection; the first NSAG information is the NSAG information associated with the first network slice.

[0258] In addition, the above components can also be used to support Figures 4 to 6 other processes performed by the terminal device in the illustrated embodiments. The beneficial effects can be referred to the previous description and will not be elaborated here.

[0259] When the communication device is a terminal device, the processor 1001 obtains cell reselection parameters configured for a frequency band based on the network slice access layer group NSAG that is valid in a specific service area through the communication interface 1002; obtains the NSAG information associated with at least one network slice that is valid in the specific service area through the communication interface 1002, where the NSAG information includes one or more of the following: the association relationship between the network slice and the NSAG identifier, the NSAG priority, the NSAG service area NSAG-AoS information, the identifier of the NSAG-AoS; the NSAG-AoS information is used to indicate one or more cells that support the NSAG; the identifier of the NSAG-AoS is used by the terminal device to distinguish NSAGs with the same NSAG identifier in different NSAG-AoSs; and performs cell reselection according to the cell reselection parameters, one or more network slices for cell reselection, and the NSAG information.

[0260] In addition, each of the above components can also be used to support Figure 7 , Figure 8 other processes performed by the terminal device in the embodiments shown. For the beneficial effects, reference can be made to the previous description and will not be elaborated here.

[0261] When the communication device is an access network device, the processor 1001 obtains network slice service area NS-AoS information corresponding to network slices supported by neighboring cells; and sends first indication information to the terminal device through the communication interface 1002, where the first indication information is used to indicate that there is a neighboring cell outside the corresponding NS-AoS of the network slice supported by the neighboring cell.

[0262] In addition, each of the above components can also be used to support Figures 4 to 6 other processes performed by the access network device in the embodiments shown. For the beneficial effects, reference can be made to the previous description and will not be elaborated here.

[0263] When the communication device is a first access network device, the processor 1001 obtains information on network slice access layer groups NSAG that are valid in a specific service area; and sends cell reselection parameters configured for a frequency band based on the NSAG that is valid in the specific service area through the communication interface 1002.

[0264] In addition, each of the above components can also be used to support Figure 7 , Figure 8 other processes performed by the access network device in the embodiments shown. For the beneficial effects, reference can be made to the previous description and will not be elaborated here.

[0265] When the communication device is a core network device, the processor 1001 receives an identifier of a network slice access layer group service area NSAG-AoS and NSAG information supported by the NSAG-AoS; and sends the NSAG information associated with at least one configured network slice of the terminal device to the terminal device through the communication interface 1002, where the NSAG information includes one or more of the following: the association relationship between the network slice and the NSAG identifier, the NSAG priority, the NSAG service area NSAG-AoS information, the identifier of the NSAG-AoS; the NSAG-AoS information is used to indicate one or more cells that support the NSAG; the identifier of the NSAG-AoS is used for the terminal device to distinguish NSAGs with the same NSAG identifier in different NSAG-AoSs.

[0266] In addition, each of the above components can also be used to support Figure 7 , Figure 8 other processes performed by the core network device in the embodiments shown. For the beneficial effects, reference can be made to the previous description and will not be elaborated here.

[0267] Based on the same inventive concept, an embodiment of the present application further provides a computer-readable storage medium. Computer-readable instructions are stored in the computer-readable storage medium. When the computer-readable instructions are run on a computer, the method according to any of the possible implementation manners described above is executed.

[0268] An embodiment of the present application provides a computer program product containing instructions. When it runs on a computer, the method embodiments described above are executed.

[0269] An embodiment of the present application provides a chip, including: a processor, which is coupled to a memory. The memory is used to store instructions. When the instructions are executed by the processor, the chip implements the method steps executed by any of the above nodes.

[0270] In the description of the embodiments of the present application, "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. The multiple referred to in the present application means two or more.

[0271] In addition, it should be understood that in the description of the present application, terms such as "first" and "second" are only used for the purpose of distinguishing descriptions, and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implying an order. The reference to "an embodiment" or "some embodiments" etc. in this specification means that a specific feature, structure, or characteristic described in combination with the embodiment is included in one or more embodiments of the present application. Thus, statements such as "in an embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments" etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "include", "comprise", "have" and their variants all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0272] The method steps in the embodiments of the present application can be implemented in a hardware manner or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in a random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, register, hard disk, removable hard disk, CD-ROM, or any other form of storage medium well-known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an ASIC. Additionally, the ASIC can be located in a base station or a terminal. Of course, the processor and the storage medium can also exist as discrete components in a base station or a terminal.

[0273] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are executed in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user device, or other programmable devices. The computer program or instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer program or instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center in a wired or wireless manner. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or a data center integrating one or more available media. The available medium can be a magnetic medium, such as a floppy disk, a hard disk, or a magnetic tape; it can also be an optical medium, such as a digital video disc; or it can be a semiconductor medium, such as a solid-state drive. The computer-readable storage medium can be a volatile or non-volatile storage medium, or can include both volatile and non-volatile types of storage media.

[0274] In the various embodiments of the present application, if there is no special description and logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced to each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0275] It can be understood that the various numerical numbers involved in the embodiments of the present application are only for the convenience of description and are not used to limit the scope of the embodiments of the present application. The magnitudes of the serial numbers of the above processes do not mean the sequence of execution, and the execution sequence of each process should be determined according to its function and internal logic.

Claims

1. A cell reselection method, characterized in that, applied to a terminal device, the method includes: obtaining network slice access stratum group (NSAG) information associated with at least one network slice; obtaining network slice service area (NS-AoS) information corresponding to at least one network slice; performing cell reselection according to one or more network slices for cell reselection, the NSAG information, and the NS-AoS information.

2. The method according to claim 1, characterized in that, the performing cell reselection according to one or more network slices for cell reselection, the NSAG information, and the NS-AoS information includes: the non-access stratum of the terminal device sends one or more network slices for cell reselection, the NSAG information, and first NS-AoS information to the access stratum of the terminal device, where the first NS-AoS information is the obtained NS-AoS information, or the NS-AoS information corresponding to the one or more network slices for cell reselection in the obtained NS-AoS information; the access stratum of the terminal device performs cell reselection according to the one or more network slices for cell reselection, the NSAG information, and the first NS-AoS information.

3. The method according to claim 2, characterized in that, the performing cell reselection according to the one or more network slices for cell reselection, the NSAG information, and the first NS-AoS information includes: sorting the frequencies for cell reselection according to one or more network slices for cell reselection, the NSAG information, and the first NS-AoS information; determining the reselection resident cell according to the sorted frequencies.

4. The method according to claim 3, characterized in that, the sorting the frequencies for cell reselection includes: sorting the frequencies for cell reselection according to at least one of the following sorting rules: the higher the priority of the NSAG, the higher the priority of the frequency supporting the NSAG; the larger the service area range corresponding to the NSAG, the higher the priority of the frequency supporting the NSAG; the larger the service area range corresponding to the NSAG means the larger the number of cells included in the NS-AoS corresponding to the network slice associated with the NSAG.

5. The method according to claim 4, characterized in that, if at least one network slice for cell reselection associated with the first NSAG has no corresponding NS-AoS information, and all network slices for cell reselection associated with the second NSAG have corresponding NS-AoS, and the service area range corresponding to the first NSAG is larger than the service area range corresponding to the second NSAG; or, if at least one network slice associated with the first NSAG has no corresponding NS-AoS information, and all network slices associated with the second NSAG have corresponding NS-AoS, and the service area range corresponding to the first NSAG is larger than the service area range corresponding to the second NSAG.

6. The method according to claim 4 or 5, characterized in that, The higher the priority of the NSAG, the higher the priority of the frequency points that support the NSAG, including: The priority of the frequency points that support the NSAG is higher than the priority of the frequency points that do not support the NSAG.

7. The method according to any one of claims 4-6, wherein, The service area range corresponding to the NSAG is determined by taking the union of the NS-AoSs corresponding to one or more network slices associated with the NSAG for cell reselection at the access stratum of the terminal device; Alternatively, the service area range corresponding to the NSAG is determined by taking the union of the NS-AoSs corresponding to one or more network slices associated with the NSAG at the access stratum of the terminal device.

8. The method according to any one of claims 1-7, wherein, After sorting the frequency points for cell reselection, the method further includes: If the access stratum of the terminal device determines that the first frequency point is the frequency point with the highest priority according to the priority of the third NSAG supported by the first frequency point and / or the service area range corresponding to the third NSAG, and the best cell or the cell with the highest ranking on the first frequency point is outside the service area range corresponding to the third NSAG, then the access stratum of the terminal device determines that the best cell or the cell with the highest ranking does not support the third NSAG.

9. The method according to claim 8, wherein, The method further includes: If the best cell or the cell with the highest ranking also supports the fourth NSAG, then the access stratum of the terminal device re-sorts the first frequency point according to the fourth NSAG information and / or the service area range corresponding to the fourth NSAG.

10. A cell reselection method, wherein, Applied to a terminal device, the method includes: Obtaining network slice access stratum group NSAG information associated with at least one network slice; Obtaining network slice service area NS-AoS information corresponding to at least one network slice; Performing cell reselection according to the first network slice and / or the first NSAG information; The first network slice is a network slice among one or more network slices for cell reselection that does not have corresponding NS-AoS information; The first NSAG information is the NSAG information associated with the first network slice.

11. The method according to claim 10, wherein, Performing cell reselection according to the first network slice and / or the first NSAG information includes: In the case of receiving first indication information, performing cell reselection according to the first network slice and / or the first NSAG information, where the first indication information is used to indicate that there is a neighboring cell outside the NS-AoS corresponding to the network slice supported by the neighboring cell.

12. The method according to claim 10, wherein, Performing cell reselection according to the first network slice and / or the first NSAG information includes: The non-access stratum of the terminal device determines the first network slice and / or the first NSAG information; The non-access stratum sends the first network slice and / or the first NSAG information to the access stratum of the terminal device; The access stratum performs cell reselection according to the first network slice and / or the first NSAG information.

13. The method according to claim 12, wherein, before the non-access stratum of the terminal device determines the first network slice and / or the first NSAG information, the method further includes: the access stratum receives first indication information, where the first indication information is used to indicate that there is a neighboring cell outside the NS-AoS corresponding to the network slice supported by the neighboring cell; the access stratum sends the first indication information to the non-access stratum; the non-access stratum of the terminal device determines the first network slice and / or the first NSAG information, including: the non-access stratum determines the first network slice and / or the first NSAG information according to the first indication information.

14. The method according to claim 10 or 11, wherein, performing cell reselection according to the first network slice and / or the first NSAG information includes: the non-access stratum of the terminal device sends one or more network slices for cell reselection, the NSAG information, and the NS-AoS information to the access stratum of the terminal device; the access stratum determines the first network slice and / or the first NSAG information; the access stratum performs cell reselection according to the first network slice and / or the first NSAG information.

15. The method according to any one of claims 11-14, wherein, the first indication information further includes: the NSAG identifier associated with the network slice corresponding to the NS-AoS information.

16. A cell reselection method, wherein, applied to a terminal device, the method includes: obtaining cell reselection parameters configured for a frequency point based on a network slice access stratum group NSAG valid in a specific service area; obtaining NSAG information associated with at least one network slice valid in a specific service area, where the NSAG information includes one or more of the following: the association relationship between the network slice and the NSAG identifier, the NSAG priority, the NSAG service area NSAG-AoS information, the identifier of the NSAG-AoS; the NSAG-AoS information is used to indicate one or more cells supporting the NSAG; the identifier of the NSAG-AoS is used for the terminal device to distinguish NSAGs with the same NSAG identifier in different NSAG-AoSs; performing cell reselection according to the cell reselection parameters, one or more network slices for cell reselection, and the NSAG information.

17. The method according to claim 16, wherein, the cell reselection parameters further include the identifier of the NSAG-AoS.

18. A cell reselection method, wherein, applied to an access network device, the method includes: obtaining network slice service area NS-AoS information corresponding to the network slice supported by a neighboring cell; sending first indication information to a terminal device, where the first indication information is used to indicate that there is a neighboring cell outside the NS-AoS corresponding to the network slice supported by the neighboring cell.

19. The method according to claim 18, wherein, the first indication information further includes: sending an NSAG identifier associated with a network slice corresponding to NS-AoS information to the terminal device.

20. A cell reselection method, wherein, applied to a first access network device, the method includes: acquiring information of a network slice access layer group (NSAG) that is valid within a specific service area; sending cell reselection parameters configured for a frequency band based on the NSAG that is valid within the specific service area according to the NSAG information.

21. The method according to claim 20, wherein, the cell reselection parameters further include an identifier of an NSAG service area (NSAG-AoS), and the identifier of the NSAG-AoS is used to distinguish and identify NSAGs with the same NSAG identifier in different NSAG-AoS information.

22. The method according to claim 20 or 21, wherein, the method further includes: sending the identifier of the NSAG-AoS and the NSAG information supported by the NSAG-AoS to a core network device.

23. The method according to any one of claims 20-22, wherein, the method further includes: sending the identifier of the NSAG-AoS and the NSAG information supported by the NSAG-AoS to a second access network device.

24. A cell reselection method, wherein, applied to a core network device, the method includes: receiving the identifier of a network slice access layer group service area (NSAG-AoS) and the NSAG information supported by the NSAG-AoS; sending the NSAG information associated with at least one configured network slice of the terminal device to the terminal device, where the NSAG information includes one or more of the following: the association relationship between the network slice and the NSAG identifier, the NSAG priority, the NSAG service area (NSAG-AoS) information, the identifier of the NSAG-AoS; the NSAG-AoS information is used to indicate one or more cells supporting the NSAG; the identifier of the NSAG-AoS is used for the terminal device to distinguish NSAGs with the same NSAG identifier in different NSAG-AoSs.

25. A communication device, wherein, includes: a processing module and a communication module, and the processing module is used to send and receive messages through the communication module and execute the method according to any one of claims 1-24.

26. A communication device, wherein, includes: a processor, the processor is coupled with a memory, and the memory is used to store programs or instructions. When the programs or instructions are executed by the processor, the device executes the method according to any one of claims 1-24.

27. A computer-readable storage medium, wherein, instructions are stored in the computer-readable storage medium. When the instructions run on a computer, the computer executes the method according to any one of claims 1-24.

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