CN113630841A

CN113630841A - Base station selection method, device, base station and storage medium

Info

Publication number: CN113630841A
Application number: CN202010379187.6A
Authority: CN
Inventors: 付昂
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2020-05-07
Filing date: 2020-05-07
Publication date: 2021-11-09
Also published as: WO2021223553A1

Abstract

The application provides a base station selection method, a base station selection device, a base station and a storage medium, wherein the base station selection method comprises the following steps: receiving an RRC establishment request message sent by UE, wherein the RRC establishment request message comprises a segment of UE identification taken from 5G-S-TMSI; determining a PLMN ID corresponding to the UE according to the mapping relation between the UE identifier and the PLMN ID; and selecting a base station corresponding to the UE according to the PLMN ID corresponding to the UE.

Description

Base station selection method, device, base station and storage medium

Technical Field

The present application relates to the field of mobile communications, and for example, to a base station selection method, apparatus, base station, and storage medium.

Background

According to the third Generation Partnership Project (3 GPP) technical standard, a Next Generation Radio Access Network (NG-RAN) includes a New Radio Node B (gNB) having a number of Next Generation (NG) interfaces connected to a fifth Generation Core Network (5 GC).

After the registration of the 5GC is successful, the 5G User Equipment (UE) obtains a 5G global Unique Temporary identifier (5G global Unique Temporary Identity, 5G-GUTI) allocated to the UE by an Access and Mobility Management Function (AMF) entity of the 5 GC. In order to make an air interface signaling smaller and improve air interface efficiency, a 5G truncated Temporary Mobile Subscriber Identity (5G shortened Mobile Subscriber Identity, 5G-S-TMSI) is introduced, wherein the 5G-S-TMSI is a shortened form of 5G-GUTI, and fields of Public Mobile Land Mobile Network Identity (PLMN ID) and AMF area Identity (AMF Region ID) are reduced on the basis of the 5G-GUTI.

However, in the NG-RAN, the gnbs may be interconnected via an Xn Control plane (Xn-C) interface. A gNB consists of a gNB Central Unit (gNB-CU) and several gNB Distributed units (gNB-DU) connected to the gNB-CU via F1 interfaces. In a radio access network sharing scenario where multiple cell identities are broadcast and the operator has an independent F1 interface, one shared gNB-DU entity may connect multiple gNB-CUs. If the UE is accessed to the shared gNB by using the 5G-S-TMSI, the shared gNB-DU cannot determine the operator to which the UE belongs because the 5G-S-TMSI does not carry the PLMN ID and the AMF Region ID, the gNB-CU with wrong access selection can be accessed, the problems of increasing gNB signaling load and UE access delay exist, and the network experience of a terminal user is reduced.

Disclosure of Invention

The application provides a base station selection method, a base station selection device, a base station and a storage medium, which can reduce the signaling overhead and access time delay of the base station and improve the user experience.

In a first aspect, an embodiment of the present application provides a base station selection method, including:

receiving an RRC establishment request message sent by UE, wherein the RRC establishment request message comprises a UE identifier which is taken from one section of 5G-S-TMSI;

determining a PLMN ID corresponding to the UE according to the mapping relation between the UE identifier and the PLMN ID;

and selecting a base station corresponding to the UE according to the PLMN ID corresponding to the UE.

In a second aspect, an embodiment of the present application provides a base station selection apparatus, including:

the receiving module is used for receiving an RRC establishment request message sent by the UE, wherein the RRC establishment request message comprises a UE identifier which is taken from one section of the 5G-S-TMSI;

the processing module is configured to determine a PLMN ID corresponding to the UE according to a mapping relation between the UE identifier and the PLMN ID;

and the selection module is set to select the base station corresponding to the UE according to the PLMN ID corresponding to the UE.

In a third aspect, embodiments of the present application provide a base station, which includes a processor and a memory, wherein the processor is configured to execute program instructions stored in the memory to perform the base station selection method of the first aspect.

In a fourth aspect, the present application provides a computer-readable storage medium, on which a computer program is stored, which when executed by a processor implements the base station selection method according to the first aspect.

Drawings

FIG. 1 is a schematic view of NG-RAN networking;

FIG. 2 is a schematic diagram of a networking scheme in which two operators share a radio access network;

fig. 3 is a signaling interaction diagram of UE initially accessing shared gNB of operator B in the networking mode shown in fig. 2;

fig. 4 is a flowchart of a base station selection method according to an embodiment;

fig. 5 is a flowchart of another base station selection method according to an embodiment;

fig. 6 is a schematic diagram of a mapping relationship between UE identities and PLMN IDs;

fig. 7 is a flowchart of a measurement statistics module of a logical gNB selection apparatus in a base station selection method according to a first embodiment;

fig. 8 is a flowchart of a logical gNB assignment module of a logical gNB selection apparatus of a base station selection method according to a first embodiment;

fig. 9 is a signaling flow diagram of UE initial access in a base station selection method according to the first embodiment;

fig. 10 is a flowchart of a measurement statistics module of a logical gNB selection apparatus in the base station selection method according to the second embodiment;

fig. 11 is a flowchart of a logical gNB assignment module of the logical gNB selection apparatus of the base station selection method according to the second embodiment;

fig. 12 is a signaling flow chart of UE initial access in the base station selection method according to the second embodiment;

fig. 13 is a flowchart of a measurement statistics module of a logical gNB selection apparatus in a base station selection method according to the third embodiment;

fig. 14 is a flowchart of a logical gNB assignment module of the logical gNB selection apparatus of the base station selection method according to the third embodiment;

fig. 15 is a signaling flow diagram of UE initial access in the base station selection method according to the third embodiment;

fig. 16 is a schematic structural diagram of a base station selection apparatus according to an embodiment;

fig. 17 is a schematic structural diagram of a base station according to an embodiment.

Detailed Description

Hereinafter, embodiments of the present application will be described in detail with reference to the accompanying drawings.

Fig. 1 is a schematic diagram of NG-RAN networking, and as shown in fig. 1, the NG-RAN includes a plurality of gnbs connected to a 5GC through an NG interface. The gNBs may be interconnected via an Xn Control plane (Xn-C) interface. A gNB consists of a gNB Central Unit (gNB-CU) and several gNB Distributed units (gNB-DU) connected to the gNB-CU via F1 interfaces.

After the 5G UE successfully registers the 5GC, the 5G-GUTI allocated to the UE by the AMF entity of the 5GC is obtained. The specific composition of the 5G-GUTI is as follows: <5G-GUTI > < PLMN ID > < AMF Region ID > < AMF Set ID > < AMF Point > <5G-TMSI >. The PLMN ID, the AMF Region ID, the AMF Set Identity (AMF Set Identity, AMF Set ID), and the AMF Pointer (AMF Pointer) together form a Globally Unique Identifier (Globally Unique AMF Identifier, GUAMI) of the AMF. The 5G Temporary Mobile Subscriber Identity (5G temporal Mobile Subscriber Identity, 5G-TMSI) is an Identity that is assigned by the AMF to the UE and is unique within the AMF.

In a radio access network sharing scenario where multiple cell identities are broadcast and the operator has an independent F1 interface, one shared gNB-DU entity may connect multiple gNB-CUs. Fig. 2 is a schematic diagram of a network configuration in which two operators share a radio access network, as shown in fig. 2. Wherein shared gNB-DU_A/BEntities are respectively connected with gNB-CU of operator A through F1 interface_AAnd gNB-CU of operator B_BConnection, gNB-CU_A5GC with operator A over NG interface_AConnection, gNB-CU_BWith operator B via NG interface5GC_BAnd (4) connecting.

Fig. 3 is a signaling interaction diagram of operator B UE initially accessing a shared gNB in the networking mode shown in fig. 2, as shown in fig. 3,

step 3010, the UE sends RRC establishment request (RRCSetuprequest) message to gNB-DU_A/BAnd the message carries the UE identity with a length of 39 bits (bit). The UE identifies the lower 39 bits from the 5G-S-TMSI. 5G-S-TMSI is a shortened form of 5G-GUTI,<5G-S-TMSI>＝<AMF Set ID><AMF Pointer><5G-TMSI>。

step 3020, gNB-DU_A/BThe operator identity PLMN ID selected by the UE cannot be derived based on the UE identity and therefore the random selection is based on operator a access. gNB-DU_A/BSending Initial uplink RRC information (F1-Initial UL RRC Message) to gNB-CU_A。

Step 3030, gNB-CU_AReplying a Downlink RRC Message Transfer (F1-DL RRC Message Transfer) Message to the gNB-DU_A/B。

Step 3040, gNB-DU_A/BSending an RRC establishment (RRCSetup) message to the UE.

Step 3050, the UE transmits an RRC setup complete (RRCSetupcomplete) message to the gNB-DU_A/BAnd the PLMN ID information carrying the UE selection is the operator B.

Step 3060, gNB-DU_A/BDetermining that a gNB-DU should be accessed based on PLMN ID information selected by a UE_B。

Step 3070, gNB-DU_A/BSending a UE Context Release Request (F1-UE Context Release Request) message to the gNB-CU_ARequesting to release the UE instance.

Step 3080, gNB-DU_A/BSending F1-Initial UL RRC Message to gNB-DU_B。

As can be seen from the signaling interaction flow shown in fig. 3, in a scenario where a radio access network broadcasting multiple cell identifiers and an operator having an independent F1 interface is used for sharing, a gbb-DU has a certain probability to select an incorrect gbb-CU, which has the problems of increasing the gbb signaling load and UE access delay, and will reduce the network experience of the terminal user.

Fig. 4 is a flowchart of a base station selection method according to an embodiment, and as shown in fig. 4, the method according to the embodiment includes the following steps.

Step S4010, receiving an RRC establishment request message sent by the UE, wherein the RRC establishment request message includes a UE identifier, and the UE identifier is taken from one segment of the 5G-S-TMSI.

The base station selection method provided by this embodiment is implemented by a gNB in an NG-RAN, and as can be known from the NG-RAN network architecture shown in fig. 1, the gNB in the NG-RAN is composed of one gNB-CU and several gNB-DUs. In a scenario of shared radio access network, the gbb-DU may be shared by multiple operators, and then one shared gbb-DU may be connected to multiple gbb-CUs, each of which belongs to one operator. The gNB-DU and the gNB-CU are both logical gNB, and the gNB-DU and the gNB-CU in one gNB can be arranged in one physical gNB or can be independent physical gNB respectively.

In the process of initially accessing the network, firstly, an RRC setup request (RRCSetupRequest) message is sent to the gNB, where the RRC setup request message carries a UE identity taken from one segment in the 5G-S-TMSI. The 5G-S-TMSI is a shortened form of the 5G-GUTI, and the PLMN ID and AMF Region ID fields are reduced on the basis of the 5G-GUTI.

The specific composition of the 5G-GUTI and the 5G-S-TMSI is as follows:

<5G-GUTI>＝<PLMN ID><AMF Region ID 8bit><AMF Set ID 10bit><AMF Pointer 6bit><5G-TMSI 32bit>，

<5G-S-TMSI>＝<AMF Set ID 10bit><AMF Pointer 6bit><5G-TMSI 32bit>。

wherein the AMF Region ID length is 8 bits, the AMF Set ID length is 10 bits, the AMF Pointer length is 6 bits, and the 5G-TMSI length is 32 bits. The PLMN ID is composed of a Mobile Country Code (MCC) and a Mobile Network Code (MNC), and the PLMN IDs of different operators are different.

However, in the scenario of sharing the radio access network as shown in fig. 2, the gNB-DU may be shared by multiple operators, the UE identifier filled in the RRC establishment request message by the UE does not carry the PLMN ID, and the gNB-DU cannot determine which operator the UE is registered in, and then a gNB-CU to which an operator belongs may be randomly selected to perform an RRC initialization process of the UE, that is, an initial RRC connection may be established for the UE according to the procedure shown in fig. 3, but this increases the signaling load of the gNB, and increases the delay of UE access.

In order to solve the above problem, the present embodiment proposes a base station selection method for selecting a gNB-CU in a process of establishing an initial RRC connection by a UE. First, a gNB-DU receives an RRC establishment request message sent by a UE, where the RRC establishment request message includes a UE identity, and the gNB-DU may be a gNB-DU shared by multiple operators or a gNB-DU to which one operator belongs. Since the RRC establishment request message received by the gNB includes the UE identity, and the UE identity does not include the PLMN ID, the gNB-DU cannot determine in which operator network the UE is registered according to the PLMN ID, and cannot determine through which gNB-CU the initial RRC establishment procedure of the UE needs to be performed.

The UE ID may be a segment in the 5G-S-TMSI, and since the AMF is a network device to which each operator belongs, each operator may encode the AMF Set ID and the AMF Pointer by using different encoding rules, and in addition, the 5G-TMSI may also formulate different encoding rules according to different operators, and therefore, a segment capable of representing different operator characteristics in the 5G-S-TMSI may be used as the UE ID. For example, the UE identity may be the lower 39 bits of the 5G-STMSI. That is to say

And the < UE identification > < AMF Set ID low bit 1bit > < AMF Pointer 6bit > <5G-TMSI 32bit >.

Step S4020, determining the PLMN ID corresponding to the UE according to the mapping relation between the UE identifier and the PLMN ID.

Although the PLMN ID is not included in the UE identity, the UE identity includes a field that can embody the features of the operator, and if the shared operators can negotiate with each other to determine the numbering rule of the core network equipment AMF and the numbering rule of the 5G-TMSI, the < UE identity > of the UE is different between different operators. After the gNB-DU acquires the UE identity, the PLMN ID corresponding to the UE can be determined according to the mapping relation between the UE identity and the PLMN ID. The mapping relationship between the UE identifier and the PLMN ID may be a preset mapping relationship, or may be a coding rule for negotiating different UE identifiers between operators, and after the UE identifier is analyzed, the operator corresponding to the UE identifier may be determined, that is, the PLMN ID corresponding to the UE identifier is determined.

For example, when the UE ID is the low 39bit of the 5G-stmi, including the low 1bit of the AMF Set ID, the AMF Pointer, and the 5G-TMSI, all are allocated to the UE by the AMF to which the operator belongs when the UE is registered in the network of the operator to which the UE belongs. If the shared operators can negotiate the numbering rules for determining the core network equipment AMF, the UE's < UE identity > will be different between different operators. After the gNB-DU acquires the UE identity, the PLMN ID corresponding to the UE can be determined according to the mapping relation between the UE identity and the PLMN ID.

Step S4030, select a base station corresponding to the UE according to the PLMN ID corresponding to the UE.

After determining the PLMN ID corresponding to the UE, the gNB-DU may determine the gNB-CU corresponding to the operator registered by the UE according to the PLMN ID. The gNB-DU may establish an initial RRC connection for the UE through the gNB-CU corresponding to the operator registered by the UE, i.e., perform step S3080. Namely, the initial uplink RRC message is sent to the gNB CU corresponding to the PLMN ID corresponding to the UE.

Therefore, the gNB-DU can accurately select the gNB-CU in the initial RRC connection establishment phase, and unnecessary signaling load increase and access delay increase caused by selecting the wrong gNB-CU are avoided.

In one embodiment, the UE identity may be taken from the lower 39 bits of the 5G truncated temporary mobile subscriber identity 5G-S-TMSI, but still longer, and the truncated UE identity may also be used as the basis for mapping with the PLMN ID. The truncated UE identity is a section of the UE identity, and the truncated UE identity is a section capable of reflecting the operator characteristics of UE registration. For example, truncating the UE identity to the highest 7 bits of the UE identity, i.e. the lowest 1bit of AMF Pointer and AMF Set ID in the 5G-S-TMSI. The concrete composition is as follows:

and (4) shortening UE identification (lower bit of AMF Set ID) < AMF Pointer 6bit >.

Then, the PLMN ID corresponding to the UE can be determined according to the mapping relation between the truncated UE identification and the PLMN ID in the 5G-S-TMSI, so that the mapping relation between the truncated UE identification and the PLMN ID only needs to be maintained in the gNB-DU, and the space in the gNB-DU can be saved. And then after the gNB-DU receives an RRC establishment request message sent by the UE, acquiring the 5G-S-TMSI therein, then determining the UE identification in the 5G-S-TMSI, determining a truncated UE identification according to the UE identification, and finally determining the PLMN ID corresponding to the UE according to the mapping relation between the truncated UE identification and the PLMN ID. Certainly, different operators need to negotiate numbering rules of the AMF, and the minimum 7-bit values of < AMF Set ID > < AMF Pointer > between different operators cannot be the same, which means that the minimum 1-bit values of < AMF Set ID > and the 7-bit values of < AMF Pointer > between different operators cannot be the same.

According to the base station selection method provided by the embodiment, after receiving the RRC establishment request message including the UE identifier sent by the UE, the PLMN ID corresponding to the UE can be determined according to the mapping relation between the UE identifier and the PLMN ID, so that the problems that the signaling overhead for establishing the initial RRC connection by the UE is large and the access delay is long due to the fact that the UE identifier sent by the UE does not have the PLMN ID and cannot determine the operator registered by the UE are solved, and the user experience is improved.

Fig. 5 is a flowchart of another base station selection method according to an embodiment, and as shown in fig. 5, the method according to the embodiment includes the following steps.

Step S5010 receives an RRC setup complete message sent by the UE, where the RRC setup complete message includes a PLMN ID selected by the UE.

According to the embodiment shown in fig. 4, if the PLMN ID corresponding to the UE is determined according to the UE identity, the mapping relationship between the UE identity and the PLMN ID needs to be maintained. And the mapping relation between the UE identification and the PLMN ID is counted after the UE completes the initial RRC connection establishment each time. When the UE completes the initial RRC connection establishment, the gNB-DU receives an RRC establishment complete message sent by the UE, and at this time, the UE has already established a connection with the gNB-CU of the operator to which the UE belongs, so that the RRC establishment complete message includes the PLMN ID that the UE has selected.

Step S5020, the mapping relation between the UE identification and the PLMN ID is counted.

And when the gNB-DU receives an RRC establishment completion message which is sent by the UE and comprises the PLMN ID selected by the UE, the mapping relation between the UE identification and the PLMN ID can be counted. The gNB-DU may establish a mapping table according to the mapping relationship, and update the mapping table each time an RRC establishment complete message including the PLMN ID selected by the UE is received, which is sent by a new UE. The mapping relation table shows the corresponding relation between different PLMN IDs and UE identifications, and the mapping relation table shows the specific mapping rules between different PLMN IDs and corresponding UE identifications because the UE identifications distributed to the UE by the same operator have certain specific rules. Then, after the gNB-DU receives the RRC establishment request message sent by the UE again, if the RRC establishment request message includes the UE identifier, the mapping relationship table may be queried, that is, the embodiment shown in fig. 4 is executed, so as to determine the PLMN ID corresponding to the UE.

Fig. 6 is a schematic diagram of a mapping relationship between a UE identity and a PLMN ID, and as shown in fig. 6, a gNB-DU maintains the mapping relationship between the UE identity and the PLMN ID in a 128 × m two-dimensional array structure. Where m represents different operators, m is 1 if there is only one operator, and m is 2 if there are two operators. The Counter in each row indicates a count, and each time the mapping table is updated according to the received PLMN ID selected by the UE, the Counter in the row corresponding to the PLMN ID is made to be Counter + 1.

In order to implement the base station selection method provided in the foregoing embodiment, the gNB-DU may include a logical gNB selection device, where the logical gNB selection device is a logical device in the gNB-DU, and may be disposed in the gNB-DU, and the base station selection method shown in fig. 4 or fig. 5 is completed by relevant components in the gNB-DU. Or the logical gNB selection apparatus may be independently disposed outside the gNB-DU and connected to the gNB-DU to complete the base station selection method in the embodiment shown in fig. 4 or fig. 5. The logic gNB selection apparatus may include a measurement statistics module and a logic gNB allocation module, where the measurement statistics module is configured to implement the base station selection method provided in the embodiment shown in fig. 5, that is, to count the mapping relationship between the UE identifier and the PLMN ID, and the logic gNB allocation module is configured to implement the base station selection method provided in the embodiment shown in fig. 4, that is, to select the PLMN ID for the UE according to the counted correspondence between the UE identifier and the PLMN ID to determine the corresponding logic gNB.

The base station selection method provided in the embodiments of the present application is further described in detail with several specific embodiments.

Example one

In this embodiment, there is only one operator a. The measurement statistics module of the logical gNB selection device maintains a mapping table as shown in fig. 6, with m taking the value 1.

Fig. 7 is a flowchart of a measurement statistics module of a logical gNB selection apparatus in a base station selection method according to a first embodiment, as shown in fig. 7:

step S7010, the measurement and statistics module executes initialization operation, including establishing 128 x 1 two-dimensional index Table [128] [1 ].

Step S7020, receiving measurement information input by an external module, wherein the measurement information comprises UE identification and PLMN ID selected by the UE_A. Setting a temporary variable to truncate the UE identity (S-UE id) ═ 7bit maximum of the UE identity. Wherein the external modules include other modules in the gNB-DU or the UE.

Step S7030, updating Table [ S-UEID ]]PLMN ID in corresponding row_AThe term Counter + 1.

Fig. 8 is a flowchart of a logical gNB allocation module of a logical gNB selection apparatus of a base station selection method according to a first embodiment, as shown in fig. 8:

step S8010, receives a logical gNB assignment request of an external module, which includes a UE identity.

Step S8020, setting a temporary variable truncated UE identifier (S-UE id) according to the UE identifier, where the truncated UE identifier is the highest 7 bits of the UE identifier.

Step S8030, using the formula

Computing Table [ S-UEID]PLMN ID in corresponding row_AWherein Counter_jRepresenting shared PLMN IDs among m operators_jThe corresponding Counter value. Calculating to obtain PLMN ID_AThe probability of (2) is 1.

Step S8040, generating a value of [0, 1]]Random numbers rand distributed uniformly in the random number rand, and the random numbers rand meet the requirement according to the rand value

Selecting PLMN ID_nFinally, selecting and outputting the PLMN ID_A。

Fig. 9 is a signaling flow diagram of UE initial access in a base station selection method according to the first embodiment, as shown in fig. 9:

step S9010, UE sends RRCSetuprequest message to gNB-DU_AAnd the message carries the UE identification with the length of 39 bits. The UE identifies the lower 39 bits from the 5G-S-TMSI.<5G-S-TMSI>＝<AMF Set ID><AMF Pointer><5G-TMSI>。

Step S9020, gNB-DU_ALogical gNB assignment module for accessing a logical gNB selection device for assignment to PLMN IDs_AThereby determining a corresponding gNB-CU_A。

Step S9030, gNB-DU_ASending F1-Initial UL RRC Message to gNB-CU_A。

Step S9040, gNB-CU_AReply F1-DL RRC Message Transfer Message to gNB-DU_A。

Step S9050, gNB-DU_AAnd sending the RRCSetup message to the UE.

Step S9060, UE sends RRCSetupcomplete message to gNB-DU_AAnd the PLMN ID information carrying the UE selection is the operator A.

Step S9070, gNB-DU_AEntering UE identity and PLMN ID_ATo the measurement statistics module of the logical gNB selection device.

Example two

In this embodiment, there are two operators, operator a and operator B, which use a gbb sharing mode in which multiple cell identifiers are broadcast and the operators have independent F1 interfaces. After negotiation between the two operators, the numbering rule of the core network equipment AMF of the operator A is the value range [0,9] of the AMF Pointer, and the numbering rule of the core network equipment AMF of the operator B is the value range [10,19] of the AMF Pointer. The measurement statistics module of the logical gNB selection device maintains a mapping table as shown in fig. 6, with m taking the value 2.

Fig. 10 is a flowchart of a measurement statistics module of a logical gNB selection apparatus in a base station selection method according to the second embodiment, as shown in fig. 10:

step S10100, the measurement and statistics module executes initialization operation, including establishing 128 x 2 two-dimensional index Table [128] [2 ].

Step S10120, receiving measurement information input by the external module, including the UE identity and the PLMN ID selected by the UE. Setting a temporary variable to truncate the UE identity (S-UE id) ═ 7bit maximum of the UE identity.

In step S10130, the PLMN ID entry Counter +1 in the Table [ S-UEID ] corresponding row is updated.

Fig. 11 is a flowchart of a logical gNB assignment module of a logical gNB selection apparatus in a base station selection method according to a second embodiment, as shown in fig. 11:

step S11010, receive the logical gNB allocation request of the external module, which includes the UE identity.

Step S11020, truncate the UE identity (S-UE id), which is the highest 7 bits of the UE identity, according to the UE identity set temporary variable.

Step S11030, using the formula

Computing Table [ S-UEID]PLMN ID in corresponding row_AWherein Counter_jRepresenting shared PLMN IDs among m operators_jThe corresponding Counter value. Calculating to obtain Table [ S-UEID ]]PLMN ID in corresponding row_AHas a probability of P_A，PLMN ID_BHas a probability of P_B. Wherein, P_AAnd P_BOne of the two is 1, and the other is 0, because the AMF Pointer number ranges of the operators a and B are different, which determines that the UE identities of the two operators are different, more precisely, the highest 7 bits of the UE identities are different.

Step S11040, generating a value of [0, 1]]Random numbers rand distributed uniformly in the random number rand, and the random numbers rand meet the requirement according to the rand value

Selecting PLMN ID_nAnd selecting and outputting the PLMN ID with the probability of 1.

Fig. 12 is a signaling flow diagram of UE initial access in the base station selection method according to the second embodiment, as shown in fig. 12:

step S12010, of operator BOne UE sends RRCSetuprequest message to gNB-DU_A/BAnd the message carries the UE identification with the length of 39 bits. The UE identifies the lower 39 bits from the 5G-S-TMSI.<5G-S-TMSI>＝<AMF Set ID><AMF Pointer><5G-TMSI>。

Step S12020, gNB-DU_A/BLogical gNB assignment module for accessing a logical gNB selection device for assignment to PLMN IDs_BThereby determining a corresponding gNB-CU_B。

Step S12030, gNB-DU_A/BSending F1-Initial UL RRC Message to gNB-CU_B。

Step S12040, gNB-CU_BReply F1-DL RRC Message Transfer Message to gNB-DU_A/B。

Step S12050, gNB-DU_A/BAnd sending the RRCSetup message to the UE.

Step S12060, the UE sends RRCSetupcomplete message to gNB-DU_A/BAnd the PLMN ID information carrying the UE selection is the operator B.

Step S12070, gNB-DU_A/BDetermining that a gNB-DU should be accessed based on PLMN ID information selected by a UE_B，gNB-DU_BEntering UE identity and PLMN ID_BTo the measurement statistics module of the logical gNB selection device.

EXAMPLE III

In this embodiment, there are two operators, operator a and operator B, which use a gbb sharing mode in which multiple cell identifiers are broadcast and the operators have independent F1 interfaces. The two operators do not negotiate, so that the numbers of core network equipment AMF of the two operators just partially overlap, namely, the values of the AMF pointers are the same, and the lowest 1bit of the AMF Set ID is also the same. The measurement statistics module of the logical gNB selection device maintains a mapping table as shown in fig. 6, with m taking the value 2.

Fig. 13 is a flowchart of a measurement statistics module of a logical gNB selection apparatus in a base station selection method according to the third embodiment, as shown in fig. 13:

step 13010, the measurement and statistics module executes initialization operation, including establishing 128 × 2 two-dimensional index Table [128] [2 ].

Step S13020, receives the measurement information input by the external module, including the UE identity and the PLMN ID selected by the UE. Setting a temporary variable to truncate the UE identity S-UEID to the highest 7 bits of the UE identity.

In step S13030, the PLMN ID entry Counter +1 in the Table [ S-UEID ] corresponding row is updated.

Fig. 14 is a flowchart of a logical gNB allocation module of a logical gNB selection apparatus in a base station selection method according to a third embodiment, as shown in fig. 14:

step S14010, receives a logical gNB assignment request of the external module, which includes the UE identity.

Step S14020, truncating the UE identity (S-UE id), which is the highest 7 bits of the UE identity, according to the UE identity setting temporary variable.

Step S14030, using the formula

Computing Table [ S-UEID]PLMN ID in corresponding row_AWherein Counter_jRepresenting shared PLMN IDs among m operators_jThe corresponding Counter value. Calculating to obtain Table [ S-UEID ]]PLMN ID in corresponding row_AHas a probability of P_A，PLMN ID_BHas a probability of P_B。

Step S14040, generating a value of [0, 1]]Random numbers rand distributed uniformly in the random number rand, and the random numbers rand meet the requirement according to the rand value

Selecting PLMN ID_nBased on P_AAnd P_BSelecting to output a PLMN ID, i.e. having P_ATo the PLMN ID_AHaving P of_BTo the PLMN ID_B。

Fig. 15 is a signaling flow diagram of UE initial access in the base station selection method according to the third embodiment, as shown in fig. 15:

step S15010, a UE of operator B sends RRCSetuprequest message to gNB-DU_A/BAnd the message carries the UE identification with the length of 39 bits. The UE identifies the lower 39 bits from the 5G-S-TMSI.<5G-S-TMSI>＝<AMF Set ID><AMF Pointer><5G-TMSI>。

Step S15020, gNB-DU_A/BLogical gNB assignment module accessing logical gNB selection device for assignment to PLMN IDs based on statistical probability_BThereby determining a corresponding gNB-CU_B。

Step S15030, gNB-DU_A/BSending F1-Initial UL RRC Message to gNB-CU_B。

Step S15040, gNB-CU_BReply F1-DL RRC Message Transfer Message to gNB-DU_A/B。

Step S15050, gNB-DU_A/BAnd sending the RRCSetup message to the UE.

Step S15060, the UE transmits an RRCSetupcomplete message to the gNB-DU_A/BAnd the PLMN ID information carrying the UE selection is the operator B.

Step S15070, gNB-DU_A/BDetermining that a gNB-DU should be accessed based on PLMN ID information selected by a UE_B，gNB-DU_BEntering UE identity and PLMN ID_BTo the measurement statistics module of the logical gNB selection device.

Fig. 16 is a schematic structural diagram of a base station selection apparatus according to an embodiment, and as shown in fig. 16, the base station selection apparatus according to the embodiment includes:

a receiving module 161, configured to receive an RRC establishment request message sent by the UE, where the RRC establishment request message includes a UE identifier, and the UE identifier is taken from one segment of the 5G-S-TMSI; the processing module 162 is configured to determine a PLMN ID corresponding to the UE according to a mapping relationship between the UE identifier and the PLMN ID; the selection module 163 is configured to select a base station corresponding to the UE according to the PLMN ID corresponding to the UE.

The base station selection apparatus provided in this embodiment is disposed in the gNB-DU and is used to implement the base station selection method in the embodiment shown in fig. 4, and the implementation principle and the technical effect of the base station selection apparatus provided in this embodiment are similar, and are not described herein again.

Fig. 17 is a schematic structural diagram of a base station according to an embodiment, and as shown in fig. 17, the base station includes a processor 171, a memory 172, a transmitter 173, and a receiver 174; the number of the processors 171 in the base station may be one or more, and one processor 171 is taken as an example in fig. 17; a processor 171 and memory 172, transmitter 173 and receiver 174 in the base station; the connection may be via a bus or other means, such as via a bus as illustrated in FIG. 17.

The memory 172 may be configured to store a software program, a computer executable program, and modules, such as program instructions/modules corresponding to the base station selection method in the embodiments of fig. 4 to 5 (for example, the receiving module 161 and the processing module 162 in the base station selection apparatus), as a computer readable storage medium. The processor 171 implements at least one functional application and data processing of the base station by running the software programs, instructions and modules stored in the memory 172, that is, the above-mentioned base station selection method is implemented.

The memory 172 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application program required for at least one function; the storage data area may store data created according to the use of the base station, and the like. Further, the memory 172 may include high speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid state storage device.

The transmitter 173 is a module or combination of devices that can transmit data over any wired or wireless network. The receiver 174 is a module or combination of devices that receives data over any wired or wireless network.

Embodiments of the present application also provide a storage medium containing computer-executable instructions, which when executed by a computer processor, are configured to perform a method of base station selection, the method comprising: receiving an RRC establishment request message sent by User Equipment (UE), wherein the RRC establishment request message comprises a UE identifier which is taken from one section of 5G-S-TMSI; determining a PLMN ID corresponding to the UE according to the mapping relation between the UE identifier and the PLMN ID; and selecting a base station corresponding to the UE according to the PLMN ID corresponding to the UE.

The above are merely exemplary embodiments of the present application, and are not intended to limit the scope of the present application.

It will be clear to a person skilled in the art that the term user terminal covers any suitable type of wireless user equipment, such as a mobile phone, a portable data processing device, a portable web browser or a car mounted mobile station.

In general, the various embodiments of the application may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the application is not limited thereto.

Embodiments of the application may be implemented by a data processor of a mobile device executing computer program instructions, for example in a processor entity, or by hardware, or by a combination of software and hardware. The computer program instructions may be assembly instructions, Instruction Set Architecture (ISA) instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source or object code written in any combination of one or more programming languages.

Any logic flow block diagrams in the figures of this application may represent program steps, or may represent interconnected logic circuits, modules, and functions, or may represent a combination of program steps and logic circuits, modules, and functions. The computer program may be stored on a memory. The memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as, but not limited to, Read-Only Memory (ROM), Random-Access Memory (RAM), optical storage devices and systems (Digital versatile disks (DVD) or Compact Disks (CD)), etc., the computer-readable medium can comprise a non-transitory storage medium, the data processor can be of any type suitable to the local technical environment, such as, but not limited to, general purpose computers, special purpose computers, microprocessors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Programmable logic devices (FGPAs), and processors based on a multi-core processor architecture.

Claims

1. A method for base station selection, comprising:

receiving a Radio Resource Control (RRC) establishment request message sent by User Equipment (UE), wherein the RRC establishment request message comprises a UE identifier which is taken from one section of a 5G truncated temporary mobile user identifier (5G-S-TMSI);

determining a PLMN ID corresponding to the UE according to the mapping relation between the UE identifier and a public mobile land network identifier (PLMN ID);

and selecting the base station corresponding to the UE according to the PLMN ID corresponding to the UE.

2. The method of claim 1, wherein the determining the PLMN ID corresponding to the UE according to the mapping relationship between the UE identity and the PLMN ID comprises:

and determining the PLMN ID corresponding to the UE according to the mapping relation between the truncated UE identifier in the UE identifier and the PLMN ID, wherein the truncated UE identifier is one section of the UE identifier.

3. The method of claim 2, wherein the determining the PLMN ID corresponding to the UE according to the mapping relationship between the truncated UE identifier in the UE identifiers and the PLMN ID comprises:

determining the UE identification, and determining a truncated UE identification according to the UE identification;

and determining the PLMN ID corresponding to the UE according to the mapping relation between the truncated UE identification and the PLMN ID.

4. The method of claim 2, wherein the determining the PLMN ID corresponding to the UE according to the mapping relationship between the truncated UE identifier in the UE identifiers and the PLMN ID comprises:

and if the truncated UE identifications corresponding to different PLMN IDs are different, determining the PLMN ID corresponding to the UE according to the mapping relation between the truncated UE identification in the UE identification and the PLMN ID.

5. The method as claimed in any one of claims 2 to 4, wherein the UE identity is the lower 39 bits of the 5G-S-TMSI, and the truncated UE identity is the highest 7 bits of the UE identity.

6. The method according to any one of claims 1 to 4, further comprising:

receiving an RRC establishment completion message sent by UE, wherein the RRC establishment completion message comprises a PLMN ID selected by the UE;

and counting the mapping relation between the UE identification and the PLMN ID.

7. The method according to any one of claims 1 to 4, wherein after determining the PLMN ID corresponding to the UE according to the mapping relationship between the UE identifier and the PLMN ID, the method further comprises:

and sending an initial uplink RRC message to a new radio node B centralized unit gNB CU corresponding to the PLMN ID corresponding to the UE.

8. A base station selection apparatus, comprising:

the system comprises a receiving module, a sending module and a receiving module, wherein the receiving module is used for receiving a Radio Resource Control (RRC) establishment request message sent by User Equipment (UE), the RRC establishment request message comprises a UE identifier, and the UE identifier is taken from one section of 5G truncated temporary mobile subscriber identity (5G-S-TMSI);

the processing module is configured to determine a Public Land Mobile Network (PLMN) ID corresponding to the UE according to a mapping relation between the UE identifier and the PLMN ID;

9. A base station comprising a processor and a memory, wherein the processor is configured to execute program instructions stored in the memory to perform a method of base station selection according to any one of claims 1 to 7.

10. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out a base station selection method according to any one of claims 1 to 7.