CN112399491B

CN112399491B - Method and device for sending and receiving historical information of UE (user equipment), main node and auxiliary node

Info

Publication number: CN112399491B
Application number: CN201910754998.7A
Authority: CN
Inventors: 王睿炜; 彦楠
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2019-08-15
Filing date: 2019-08-15
Publication date: 2022-08-16
Anticipated expiration: 2039-08-15
Also published as: CN115361712A; CN112399491A

Abstract

The embodiment of the invention discloses a method and a device for sending and receiving UE (user equipment) historical information, a main node and an auxiliary node, wherein the method for sending the UE historical information comprises the following steps: sending a request message to an auxiliary node (SN), wherein the request message carries first UE historical information; wherein the first UE history information comprises one or more of: primary cell information of the SN, secondary cell information of the SN, and beam information of each cell. According to the embodiment of the invention, the SN can select the best cell or beam by combining the cell or beam information recorded in the UE historical information by carrying the UE historical information in the request message, so that the service quality and the success rate of terminal access are improved, and the performance of the terminal after access is improved.

Description

Method and device for sending and receiving historical information of UE (user equipment), main node and auxiliary node

Technical Field

The invention relates to the technical field of communication, in particular to a method and a device for sending and receiving historical information of UE, a main node and an auxiliary node.

Background

With the development of 5G communication technology, in order to achieve better user experience and faster transmission rate, a multi-connection technology and a Carrier Aggregation (CA) technology are proposed.

The NR new air interface supports a MR-DC (Multi-Radio Dual Connectivity, Dual Connectivity under multiple access technologies) architecture, in which a UE (terminal) may simultaneously access two base stations, namely, an MN (Master Node) and an SN (Secondary Node), where the MN and the SN may be different communication systems, and there may be multiple access cells. For example, when MN is LTE (Long Term Evolution) node and SN is NR (New Radio communication) node, it is EN-DC (eNB NR Dual Connection, 4G-5G base station Dual Connection); NE-DC (NR eNB Dual Connection, 5G-4G base station Dual Connection) when MN is NR node and SN is LTE node; when both MN and SN are NR nodes, NR-NR-DC (NR eNB Dual Connection, 5G-5G base station Dual Connection) Dual Connection is adopted. Each cell may contain multiple beams and the terminal actually accesses under a certain beam in the cell.

The carrier aggregation technology is that one UE can be connected to multiple cells simultaneously, and the cells share one MAC (Media Access Control), and are scheduled by a network in a unified manner. The cell with the control plane connected thereto is a PCell (Primary cell), and the other cells that only perform data transmission are scells (Secondary cells).

Besides the main service cell, the multi-connection technology or the carrier aggregation technology can realize that the main and auxiliary cells jointly serve the terminal by adding the auxiliary nodes, the auxiliary cells and other technologies, solve the network problems of blind supplement and heat supplement and the like, and improve the user experience.

In the prior art, a terminal reporting mode is adopted to realize the selection of the auxiliary cells or beams, that is, the terminal reports a plurality of candidate cells meeting conditions, and the base station selects the candidate cells according to a specific algorithm. However, because the information of the reported cell is incomplete, the best secondary cell or beam cannot be selected, and thus the user cannot access the cell or the performance of the accessed cell is poor.

Disclosure of Invention

Because the existing method has the problems, the embodiments of the present invention provide a method and an apparatus for sending and receiving UE history information, a primary node, and a secondary node.

In a first aspect, an embodiment of the present invention provides a method for sending history information of a UE, including:

sending a request message to an SN, wherein the request message carries first UE historical information;

wherein the first UE history information comprises one or more of: primary cell information of the SN, secondary cell information of the SN, and beam information of each cell.

In a second aspect, an embodiment of the present invention further provides a UE history information receiving method, including:

receiving a request message sent by an MN, wherein the request message carries first UE history information;

In a third aspect, an embodiment of the present invention further provides a method for sending UE history information, where the method includes:

sending a modification request message to an MN, wherein the modification request message carries second selection information, and the second selection information is indication information of an SN (service provider) actively selecting a modified cell and/or beam, so that the MN updates first UE (user equipment) historical information according to the second selection information;

In a fourth aspect, an embodiment of the present invention further provides a method for sending history information of a UE, where the method includes:

sending a UE context establishing message to a distribution unit DU, wherein the UE context establishing message carries UE historical information;

wherein the UE history information comprises one or more of: primary cell information, secondary cell information, beam information of each cell.

In a fifth aspect, an embodiment of the present invention further provides a UE history information receiving method, including:

receiving a UE context establishment message sent by a central unit CU, wherein the UE context establishment message carries UE history information;

selecting a corresponding cell and/or beam according to the UE context establishment message to obtain a selection result, and sending the selection result to the CU;

In a sixth aspect, an embodiment of the present invention further provides a UE history information sending apparatus, including:

a request message sending module, configured to send a request message to an SN, where the request message carries first UE history information;

In a seventh aspect, an embodiment of the present invention further provides a UE history information receiving apparatus, including:

a request message receiving module, configured to receive a request message sent by an MN, where the request message carries first UE history information;

In an eighth aspect, an embodiment of the present invention further provides a UE history information sending apparatus, including:

a modification request message sending device, configured to send a modification request message to an MN, where the modification request message carries second selection information, and the second selection information is indication information of an SN actively selecting a modified cell and/or beam, so that the MN updates first UE history information according to the second selection information;

In a ninth aspect, an embodiment of the present invention further provides a UE history information sending apparatus, including:

a context establishing message sending module, configured to send a UE context establishing message to a distribution unit DU, where the UE context establishing message carries UE history information;

In a tenth aspect, an embodiment of the present invention further provides a UE history information receiving apparatus, including:

the system comprises a context establishing message receiving module, a context establishing message sending module and a context establishing message sending module, wherein the context establishing message is used for receiving a UE context establishing message sent by a central unit CU, and the UE context establishing message carries UE historical information;

a cell and beam selection module, configured to select a corresponding cell and/or beam according to the UE context setup message, obtain a selection result, and send the selection result to the CU;

In an eleventh aspect, an embodiment of the present invention further provides a MN, including a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor executes the program to perform the following steps:

sending a request message to an auxiliary node (SN), wherein the request message carries first UE historical information;

In a twelfth aspect, an embodiment of the present invention further provides a SN, including a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor executes the computer program to perform the following steps:

In a thirteenth aspect, an embodiment of the present invention further provides a SN, including a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor executes the computer program to perform the following steps:

In a fourteenth aspect, an embodiment of the present invention further provides a CU, including a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor executes the computer program to perform the following steps:

In a fifteenth aspect, an embodiment of the present invention further provides a DU, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor executes the computer program to perform the following steps:

In a sixteenth aspect, an embodiment of the present invention further provides a non-transitory computer-readable storage medium, where the non-transitory computer-readable storage medium stores a computer program, and the computer program causes the computer to execute the UE history information sending method.

In a seventeenth aspect, an embodiment of the present invention further provides a non-transitory computer-readable storage medium, where the non-transitory computer-readable storage medium stores a computer program, and the computer program causes the computer to execute the UE history information receiving method.

According to the technical scheme, the SN can select the best cell or beam by combining the cell or beam information recorded in the UE historical information through carrying the UE historical information in the request message, so that the service quality and the success rate of terminal access are improved, and the performance of the terminal after the terminal access is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic diagram of a handover process of an LTE system provided in the prior art;

fig. 2 is a schematic flow chart of Xn handover in an NR system provided in the prior art;

fig. 3 is a schematic flow chart of NG handover in the NR system provided by the prior art;

fig. 4 is a schematic diagram of an SN adding scenario provided in the prior art;

FIG. 5 is a schematic diagram of a SN addition process provided by the prior art;

fig. 6 is a flowchart illustrating a method for sending history information of a UE according to an embodiment of the present invention;

fig. 7 is a schematic diagram illustrating UE history information according to an embodiment of the present invention;

fig. 8 is a schematic view illustrating an adding flow of a secondary node according to an embodiment of the present invention;

fig. 9 is a flowchart illustrating a method for receiving history information of a UE according to an embodiment of the present invention;

fig. 10 is a flowchart illustrating a method for sending history information of a UE according to another embodiment of the present invention;

fig. 11 is a flowchart illustrating a method for sending history information of a UE according to another embodiment of the present invention;

fig. 12 is a flowchart illustrating a method for receiving history information of a UE according to another embodiment of the present invention;

fig. 13 is a schematic structural diagram of an apparatus for sending history information of UE according to an embodiment of the present invention;

fig. 14 is a flowchart illustrating a method for receiving history information of a UE according to an embodiment of the present invention;

fig. 15 is a schematic structural diagram of an apparatus for sending history information of UE according to another embodiment of the present invention;

fig. 16 is a schematic structural diagram of an apparatus for sending history information of UE according to yet another embodiment of the present invention;

fig. 17 is a schematic structural diagram of a UE history information receiving apparatus according to another embodiment of the present invention;

fig. 18 is a logic block diagram of an MN provided in accordance with an embodiment of the present invention;

FIG. 19 is a logic diagram of an SN according to an embodiment of the present invention;

FIG. 20 is a logic diagram of an SN provided by another embodiment of the present invention;

FIG. 21 is a logic block diagram of a CU in accordance with an embodiment of the present invention;

fig. 22 is a logic block diagram of a DU according to an embodiment of the present invention.

Detailed Description

The following further describes embodiments of the present invention with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

Before the present invention is described, techniques related to the present invention are described:

the terminal history information (hereinafter, referred to as UE history information) includes a cell where the terminal is camped on/accessed and access time. Both the base station and the terminal maintain respective UE history information, with similar contents but with some differences:

the UE history information maintained by the base station comprises the time information of each PCell access of the terminal in a connected state. And during switching, sending the switching request message to a switching target base station, and continuously maintaining by the switching target base station. Since the base station is not aware of the situation of the terminal in the idle state, the UE history information maintained by the base station does not include information of the terminal in the idle state.

The UE history information maintained by the terminal includes the records of PCell in idle and connected states. The network side is obtained through special signaling message acquisition, which needs the support of terminal capability.

The base station maintains and transfers the UE history information during handover, which mainly includes S1 and X2 handover in LTE system, and Xn handover and NG (Next Generation) handover in NR system.

The handover procedure in the LTE system is shown in fig. 1, and includes the following steps:

measurement Control;

measurement reports;

HO decision;

handover Request;

admission Control (access Control);

handover Request Ack (handover Request acknowledgement);

handover Command (Handover Command);

synchronization (synchronization);

handover Required (handover request);

handover Request;

(ii) Admission Control;

handover Request Ack (Handover Request acknowledgement);

handover Request Ack (handover Request acknowledgement);

handover Command;

synchronization (synchronization).

Wherein step 1/2/3 and steps 4 a-8 a are X2 handover, UE history information is sent to the target base station in message 4aHANDOVER REQUEST. Wherein, the step 1/2/3 and the steps 4b to 10b are S1 HANDOVER, and the UE history information is sent to the target base station through the core network in the message 4b and the message 5b HANDOVER request and HANDOVER request.

In the NR system, the Xn handover procedure is shown in fig. 2, involving interaction between UE (terminal), Source gNB (Source base station) and Target gNB (Target base station):

HANDOVER REQUEST;

HANDOVER REQUEST ACKNOWLEDGE (HANDOVER REQUEST ACKNOWLEDGE);

RRC Reconfiguration (Radio Resource Control) Reconfiguration);

RRC Reconfiguration Complete.

Wherein the HANDOVER REQUEST message is transmitted from the source base station to the target base station.

NG handover procedure as shown in fig. 3, involves interaction between UE (terminal), Source gbb (Source base station), AMF (Access and Mobility Management Function) and Target gbb (Target base station):

HANDOVER REQUIRED (Handover request);

HANDOVER REQUEST;

HANDOVER REQUEST ACKNOWLEDGE (HANDOVER REQUEST ACKNOWLEDGE);

HANDOVER COMMAND;

RRC Reconfiguration (radio resource control Reconfiguration);

RRC Reconfiguration Complete (radio resource control Reconfiguration Complete).

Wherein, the UE history information in the HANDOVER REQUERED and HANDOVER REQUEST messages is transferred to the target base station by the source base station through AMF.

The NR new air interface supports MR-DC architecture, i.e. dual connectivity under multiple access technologies. Taking an EN-DC scenario as an example, as shown in fig. 4, the SN adding scenario is shown, if a terminal (not shown) accesses an eNB as a MN (primary node) and accesses an EN-gbb as an SN (secondary node), and a connection structure diagram is shown in fig. 4, this special multi-connection scenario is called an EN-DC scenario. The corresponding secondary node addition procedure is shown in fig. 5, involving the interaction of one terminal (UE), one primary node (MN) and multiple secondary nodes (SN1, SN2, … …, SNn):

step 0: the terminal reports a Measurement report (Measurement report) according to the base station Measurement configuration information, wherein the Measurement report comprises Measurement results of a plurality of cells measured by the terminal;

step 1: the MN organizes the SGNB ADDITION REQUEST message to send to the SNs, and may send an SGNBADDITION REQUEST message to each SN if the measurement report contains cells of multiple SNs. The measurement results for multiple cells may be included in each SGNB ADDITION REQUEST message.

Step 2: the SN receives the SGNB ADDITION REQUEST message, determines an appropriate PSCell/SCell/beam (Primary Secondary Cell), organizes the SGNB ADDITION REQUEST ACKNOWLEDGE, and transmits the result to the MN.

And step 3: the MN base station receives the SGNB ADDITION REQUEST acknowledgement message replied by the plurality of SNs, selects a proper SN according to an algorithm, and organizes RRCConnectionReconfiguration (radio resource control connection Reconfiguration) message to be sent to the terminal.

Step 4-6: and the terminal performs random access in the target cell according to the content of the RRCConnectionReconfiguration message, and completes the process of adding the auxiliary node.

Specifically, the MN is mainly divided into two phases when adding/modifying PSCell/SCell/beam of SN:

in the first stage, after receiving a SN addition/modification request message sent by an MN, an SN needs to select an optimal PSCell/SCell/beam in a local base station; and when the SN successfully processes the request message, replying a response message to the MN base station.

In the second stage, the MN selects response messages sent by a plurality of SNs. The existing selection algorithm is mainly based on measurement report of the terminal, but the PSCell/SCell/beam selection often fails due to the influence of mobility and channel fading of the terminal.

In the process of adding/deleting/modifying the SCell and the related beam on the MN side, the existing UE historical information does not contain SCell/beam related information, and only the measurement report content of the terminal is referred, so that poor selection is caused.

In view of the above situation, the present invention provides a method for increasing UE history information, which assists the MN to perform the best SN and SCell, and also assists the SN to select the best SCell and beam, thereby improving the success rate of NM and SN selection.

Fig. 6 shows a flowchart of a UE history information sending method according to this embodiment, including:

s601, sending a request message to an auxiliary node SN, wherein the request message carries the history information of the first UE.

The primary cell information of the SN includes: access time length or cell identification information.

The secondary cell information of the SN includes: access time length or cell identification information.

The cell identification information is a global cell identification code, or a physical cell identification is combined with a frequency point.

The beam information is a beam index used when the access is successfully performed for the first time in the current cell, or all the beam indexes and access time lengths used in the current cell.

Specifically, the two recording modes of beam information specifically include:

the first method is as follows: and recording only the beam index used for the first time after the cell is successfully and randomly accessed. In the random access process, the access success rate higher than that of the competitive random access can be obtained by using the non-competitive random access resources. The non-competitive resources can avoid resource collision in the random access process, and the failure probability is reduced. In the non-competitive random access resources, the base station configures the SSBs used for random access, so that the problem that the terminal can not select the appropriate SSBs because the SSBs are randomly selected according to the protocol requirement is avoided. In the case where the random access fails due to the collision or improper selection of the SSBs, the terminal repeats the SSB selection and the random access if the maximum number of attempts is not reached, which increases the access delay.

In the procedures of handover, SN addition/modification, SCell addition, and the like, the larger the delay of random access is, the more likely the mobile terminal may cause a change in the radio environment due to the rayleigh fading characteristics of the channel, and the more likely the mobile terminal may cause a failure. Therefore, the present embodiment uses non-contention random access resources in the random access procedure.

In the processes of handover, SN addition/modification, SCell addition, etc., when non-contention resource allocation is performed, appropriate SSBs first need to be selected. And using the SSB index which is recorded in the UE history information and is successfully used for random access as a reference to improve the probability of selecting proper SSBs.

The second method comprises the following steps: and recording all used beams in the cell and the total time of each beam according to the sequence of accessing the beams by the UE. Examples are as follows: the beam index of the UE is 3, 2, 1, 2 and 1, and the time length of each beam access is 5s, 4s, 3s, 2s and 1s respectively. The final record form is:

beam index	3	2	1
				Length of access time	5s		4+2＝6s	3+1＝4s

This recording approach requires more memory and processing, but can provide more information than the first approach.

Specifically, as shown in fig. 7, a schematic diagram of UE history information provided in this embodiment is shown, where the UE history information includes visited cell lists (visited cell list 0, visited cell list 1 … … visited cell list 15), and each visited cell list includes four items: PCell cell identification information, PCell access time length, cell identification information of a PSCell or SCell, access time length of a PSCell or SCell. In the embodiment, by adding the two contents in the UE history information locally stored in the MN, the MN is convenient to determine the performance of the UE connected to each PSCell or SCell according to the cell identification information of the PSCell or SCell to which the UE is connected and the access time length of the PSCell or SCell, so as to select the SN corresponding to the optimal PSCell or SCell for the UE to access.

In this embodiment, beam information of each cell, that is, the content of the dashed box in fig. 7, is also added, so that it is convenient for the MN to determine the performance of the UE connecting to each beam according to the condition of the beam to which the UE has connected, and thus select the SN corresponding to the best beam for the UE to access.

The PSCell or SCell mainly faces a multi-connection scenario or a carrier aggregation scenario, and records related information of multiple serving cells.

The request message carries indication information for adding, deleting or modifying the cell and/or the beam under the SN.

Specifically, after the MN selects the best SN according to the UE history information, an add/delete/modify request message is sent to the SN, and the SN is notified to add/delete/modify the corresponding cell or beam according to the add/delete/modify request message.

For example, as shown in fig. 8, after the UE accesses the MN, the MN acquires UE information, including UE history information; the UE reports a Measurement report, then the MN selects a target cell, namely a target SN, according to the Measurement report and UE historical information, and sends a SgNB Addition Request to the target SN. In the SN adding process, the SN adding request message carries UE history information, so that when the SN selects a corresponding cell or beam, the SN can select an optimal cell or beam by referring to the UE history information.

Specifically, after the MN receives the measurement report reported by the UE, the MN obtains the UE history information locally stored in the MN instead of directly selecting the target cell to which the UE needs to connect according to the measurement report. The UE history information includes time information of each PCell access by the terminal in a connected state. The SN and the target cell are determined by combining the measurement report and the UE historical information, so that after the terminal accesses the target cell of the SN, a better access effect can be obtained, and the terminal is prevented from accessing the cell which is recorded in the UE historical information and fails in access again. When the MN selects the PSCell/SCell/beam, the cell and the beam with the highest power in the history are selected, and a plurality of beams can be selected to improve the access success rate.

In this embodiment, the request message carries the UE history information, so that the SN can select the best cell or beam by combining the cell or beam information recorded in the UE history information, thereby improving the service quality and success rate of terminal access and improving the performance of the terminal after access.

Further, on the basis of the above method embodiment, the UE history information sending and processing method further includes:

receiving a request response message returned by the SN, wherein the request response message carries first selection information, and the first selection information is indication information of a cell and/or a beam selected by the SN according to the request message; or the like, or, alternatively,

and receiving a modification request message sent by the SN, wherein the modification request message carries second selection information, and the second selection information is indication information of the SN actively selecting the modified cell and/or beam.

Specifically, after receiving the request message, the SN selects a corresponding cell and/or beam according to the UE history information carried in the request message, records the selection as the first selection information, and informs the MN of detailed selection information by carrying the first selection information in a request response message returned to the MN, thereby facilitating the MN to update local UE history information according to the first selection information.

In another embodiment, the SN does not receive the request message sent by the MN, actively selects the corresponding cell and/or beam to modify, records the information of this modification as the second selection information, and informs the MN of the detailed selection information in the modification request message sent to the MN, so that the MN can update the local UE history information according to the second selection information conveniently.

Further, on the basis of the above method embodiment, the method for sending and processing UE history information further includes:

updating the first UE history information according to the first selection information or the second selection information; and/or the presence of a gas in the gas,

and acquiring second UE historical information of the UE side, and updating the current UE historical information of the MN according to the second UE historical information.

Specifically, when the MN receives selection information (first selection information or second selection information) sent by the SN, local UE history information is updated according to the selection information.

In order to ensure the integrity and accuracy of the UE historical information of the local MN, the MN periodically acquires the UE historical information of the UE side and updates the UE historical information of the local MN according to the UE historical information of the UE side.

The first UE history information is UE history information before local update of the MN, and the second UE history information is UE history information of the UE side.

Specifically, when the MN maintains the UE history information, three scenarios are distinguished: SN add/delete/modify scenarios.

The SN adding scene refers to that the SN is initiated by the MN and provides service for allocating resources for the user.

The SN deletion scenario may be initiated by the MN or by the SN, and the resource allocated to the user at the SN is released.

The SN modification scenario may be initiated by the MN or by the SN to modify the SCG configuration within the SN, e.g., change of PSCell.

Each scene change is shown in the following table

For the SN addition scenario, attention is paid to the SN addition of one row. Terminal primary cell access cell ID: a, the accessed beam indexes are 0 and 1, and no auxiliary node exists at the moment. The corresponding UE history information is shown as UE history information (one) in the following table:

UE history information 1
	Node 0
Primary cell a
	BEAM 0，1
Access time of

After SN is added, the information of the primary cell is unchanged, and the ID of the primary cell and the ID of the secondary cell are added: b, the index of the accessed beam is 2 and 3. At this time, a node is added to the UE history information, and the corresponding UE history information is shown as UE history information (two) in the following table:

the corresponding UE history information in other scenarios is shown in the following table as UE history information (three) and (four), respectively:

the MN will maintain UE history information when the MN adds/deletes/modifies SNs. Specifically, in the EN-DC secondary node ADDITION flow, after the SN performs PSCell/SCell/beam selection, a SN ADDITION response message SGNB ADDITION REQUEST ACKNOWLEDGE is sent to the MN. The message comprises CG-Config information, scg-CellGroupConfig information is carried in the CG-Config information in a code stream form, the code stream can be directly spliced in an RRC reconfiguration message to be sent to the terminal, and decoding by the MN is not needed, so that the MN is not clear of the specific PSCell/SCell/beam configuration condition of the SN, and the PSCell/SCell/beam configuration condition needs to be added in the CG-Config information in an explicit mode, so that the MN maintains UE history information to know the condition of the SN.

Similarly, in the EN-DC secondary node MODIFICATION process, the SGNB MODIFICATION REQUEST acknowledgement message and the SGNB MODIFICATION REQUEST message also include CG-Config information, and the PSCell/SCell/beam configuration needs to be explicitly increased, so that in the secondary node MODIFICATION scenario, the MN can know the configuration on the SN side.

In addition, in the procedure of deleting the EN-DC auxiliary node, the MN may delete the SN content in the UE history information when sending the RRC reconfiguration message, and count the SN access time length.

In the SN adding/modifying process, the terminal may need to perform random access in the SN, and since the sequence of the random access and the reply of the RRC reconfiguration complete message to the MN depends on the implementation of the terminal, the MN side cannot know the exact effective time of SN addition/modification in time, which affects the statistics of SN-related access time in the UE history information. There are two solutions: one is to advance the effective time to the moment when the MN sends the RRC reconfiguration, if the following process fails, the MN returns back the related nodes of the UE historical information when receiving the failure message; the other is that after the random access of the SN side is successful, the MN is informed by using an SGNB MODIFICATION request message, and the time when the message is received by the MN is used as the effective time of SN addition/MODIFICATION.

It should be noted that the UE history information maintained by the SN only includes relevant information accessed by the terminal in the connected state, and does not include the idle state, and after the terminal is released, the SN no longer stores the UE context information, that is, the UE history information stored by the SN only includes content after this access.

The UE history information maintained by the UE includes contents of a connected state and an idle state, the maximum number of records is the same as that of the UE side, and the number of records is 16, but since the recorded state contents are many, it is possible that older records are already covered.

Therefore, the MN comprehensively summarizes the UE historical information of the SN side and the UE side, and can obtain more complete information.

Further, on the basis of the above embodiment of the method, before S601, the method further includes:

and selecting the SN according to the first UE historical information.

By adding PSCell or SCell cell identification information, access time length and beam information of each cell in the first UE historical information, the accuracy of the MN in SN selection is higher.

Fig. 9 shows a flowchart of a UE history information receiving method provided in this embodiment, where the method includes:

s901, receiving a request message sent by an MN, wherein the request message carries first UE history information;

the first UE history information is information carried in a request message sent by the MN to the SN, so that the composition of the first UE history information in this embodiment is completely the same as that of the first UE history information in the corresponding embodiment of fig. 6, and is not described here again.

The request response message carries indication information of adding, deleting or modifying the cell and/or the beam by the SN.

Specifically, after selecting the best SN according to the UE history information, the MN sends an add/delete/modify request message to the SN, and notifies the SN to add/delete/modify the corresponding cell or beam according to the add/delete/modify request message. After receiving an addition/deletion/modification request message sent by the MN, the SN selects a corresponding cell or beam according to first UE historical information carried in the addition/deletion/modification request message, records the selection as first selection information, and carries the first selection message in an addition/deletion/modification request response message returned to the MN to inform the MN of detailed selection information, so that the MN can update local UE historical information according to the first selection information conveniently.

Further, on the basis of the above method embodiment, the UE history information receiving and processing method further includes:

and returning a request response message to the MN according to the request message, wherein the request response message carries first selection information, and the first selection information is indication information of a cell and/or a wave beam selected by the SN according to the request message.

And selecting a corresponding cell and/or beam according to the historical information of the first UE.

Specifically, in the PSCell/SCell/beam selection process, taking an EN-DC secondary node addition flow as an example, as shown in fig. 8, the method includes the following steps:

0, acquiring UE information;

measurement report;

2. selecting a target cell;

sgnb Addition Request (secondary node Addition Request);

4. selecting a target cell and beam;

sgnb Addition Request acknowledgement (secondary node Addition Request acknowledgement);

6. judging a target cell;

RRC Reconfiguration (radio resource control Reconfiguration);

RRC Reconfiguration Complete.

In the step 2, when the MN selects PSCell/SCell/beam, the MN determines the target cell reported by measurement after receiving the measurement report, and if the target cell access time in the UE history information is too short, the SN will not initiate an SGNB ADDITION REQUEST message any more, thereby reducing the signaling load and the processing delay.

In step 3, the SGNB ADDITION REQUEST message is added with the UE history information, which includes the extended content of the UE history information, i.e., the content in the dashed box of fig. 7.

In step 4, when the SN selects the PSCell/SCell/beam, the SN receives an SGNB ADDITION REQUEST message and then selects the PSCell/SCell/beam. The existing algorithm only measures the reported information by the terminal transmitted by the MN, the embodiment increases the input of the historical information of the UE, selects the cell and the beam with the highest power in the history, and the beam can select a plurality of cells so as to improve the access success rate.

In step 6, when the MN selects the optimal SN, the MN receives an SGNB ADDITION REQUEST ACKNOWLEDGE message (secondary node ADDITION REQUEST ACKNOWLEDGE) of a plurality of SNs, and needs to select an appropriate SN in consideration of a plurality of factors such as loads of the plurality of SNs, corresponding time of the message, and History Information of the UE, so as to improve a success rate of SN ADDITION.

In the SN modification process, the PSCell/SCell/beam may need to be changed, and the selection of the best PSCell/SCell/beam also needs to be performed. The method comprises two scenes of MN triggering and SN triggering.

Specifically, when the SN actively triggers the SN modification request message, it is to inform the MN of the current SN configuration.

Fig. 10 shows a flowchart of a UE history information sending method provided in this embodiment, where the method includes:

s1001, sending a modification request message to the MN, wherein the modification request message carries second selection information, and the second selection information is indication information of an SN actively selecting a modified cell and/or beam, so that the MN updates the history information of the first UE according to the second selection information.

The first UE history information is UE history information locally stored by the MN, so that the composition of the first UE history information in this embodiment is completely the same as that of the first UE history information in the corresponding embodiment of fig. 6, and is not described here again.

It should be noted that the second selection message records the cell and/or beam actively selected by the SN, and therefore the content recorded by the second selection message is actually part of the history information of the first UE.

In particular, the MN triggered SN MODIFICATION flow is similar to fig. 8, with messages 3 and 5 being modified to SGNB MODIFICATION REQUEST and SGNB MODIFICATION REQUEST ACKNOWLEDGE messages, respectively.

The SN-triggered SN MODIFICATION procedure involves also SGNB MODIFICATION request and SGNB MODIFICATION CONFIRM. The SGNB MODIFICATION REQUEST message needs to add UE history information, and is transmitted between the MN and the SN to assist in selection.

In this embodiment, when the SN actively triggers the SN modification request message, the modification request message carries the selection information of the cell and/or the beam to notify the MN of the current SN configuration, which is convenient for the MN to maintain local UE history information.

Fig. 11 shows a flowchart of a UE history information sending method provided in this embodiment, where the method includes:

s1101, sending a UE context establishing message to a DU, wherein the UE context establishing message carries UE history information;

The UE history information in this embodiment is UE history information locally stored by the base station, so the composition of the first UE history information in this embodiment is completely the same as that of the first UE history information in the corresponding embodiment in fig. 6, and is not described here again.

In the prior art, when a CU sends a UE context setup message to a DU, the UE context setup message also carries UE history information, but since there is no beam information in the existing UE history information, the DU only refers to the current situation of a base station when selecting beams, and the selected beams may not be used.

In this embodiment, by adding the cell and beam information to the UE history information, the DU can select the best cell or beam by combining the cell and/or beam information recorded in the UE history information, so as to improve the service quality and success rate of terminal access and improve the performance of the terminal after access.

Further, on the basis of the above method embodiment, the method for sending UE history information further includes:

receiving a selection result returned by the DU, wherein the selection result carries the cell and/or beam selected by the DU;

and updating the UE historical information according to the selection result.

Specifically, after the DU selects a cell and/or a beam, a selection result is returned to the CU, so that the CU updates local UE history information.

Fig. 12 shows a flowchart of a UE history information receiving method according to this embodiment, which includes:

s1201, receiving a UE context establishment message sent by a CU, wherein the UE context establishment message carries UE history information;

s1202, selecting a corresponding cell and/or beam according to the UE context establishment message to obtain a selection result, and sending the selection result to the CU;

The UE history information in this embodiment is UE history information locally stored in the base station, so that the composition of the first UE history information in this embodiment is completely the same as that of the first UE history information in the corresponding embodiment of fig. 6, and is not described here again.

Specifically, the record mode of the beam information specifically includes:

the first method is as follows: and recording only the beam index used for the first time after the cell is successfully and randomly accessed. In the random access process, the access success rate higher than that of the competitive random access can be obtained by using the non-competitive random access resources. The non-competitive resources can avoid resource collision in the random access process, and the failure probability is reduced. In non-competitive random access resources, the base station configures the SSBs used by random access, so that the problem that the terminal randomly selects the SSBs according to protocol requirements and possibly cannot select proper SSBs is avoided. In the case where random access fails due to the collision or improper selection of SSBs, if the maximum number of attempts is not reached, the terminal repeats SSB selection and random access, which increases access delay.

The second method comprises the following steps: and recording all used beams in the cell and the total time of each beam according to the sequence of accessing the beams by the UE. Examples are as follows: the UE accesses the

beam indexes

3, 2, 1, 2 and 1 successively, and the time length of each beam access is 5s, 4s, 3s, 2s and 1s respectively. The final record form is:

beam index	3	2	1
				Total time of day	5s		4+2＝6s	3+1＝4s

When the RRC acquires the beam information, the UE randomly accesses the beam successfully, and on the base station side, the current CU (Centralized Unit) cannot acquire the beam information, and the DU (Distributed Unit) can know the beam index information accessed by the UE, and the history information of the UE is maintained by the CU and needs to be notified to the RRC by the DU.

For the first method for recording beam information, under the CUDU architecture, beam index information needs to be added to the UL RRC MESSAGE TRANSFER message of the F1 interface to notify a CU.

For the second recording mode of the beam information, under the CUDU framework, the DU is required to maintain the beam index and the access time for informing the UE of accessing, when the CU requests, the DU sends the beam information to the CU, and a pair of messages needs to be added on an F1 interface to complete the function.

For the network side, the CU needs to acquire beam information when maintaining UE history information, and the beam information needs to be added to a message sent to the CU by the DU.

In addition, UE history information is added in the UE context establishing message of the F1 interface, which is convenient for the DU to refer to the UE history information content for making various judgments.

Specifically, in a carrier aggregation scenario, in the prior art, selection is performed according to a measurement report reported by a terminal, and no history information is referred to. In this embodiment, the UE history information is extended and then the information for accessing the secondary cell is added, so that the selection can be performed by using an auxiliary algorithm. When the method is realized, a time threshold value setting mode can be adopted, the time threshold value is reduced for the auxiliary cell with high success rate, and the time threshold value is raised for the auxiliary cell with low success rate; or the same measurement standard can be adopted, and different priorities are adopted for distinguishing when the target cell is selected after the terminal is measured and reported.

In a handover scenario, an existing target base station needs to generate a handover command with reference to UE measurement report and UE history information content. Under the CUDU architecture, since the CellGroupConfig information is generated by the DU, that is, the selection of the handover target cell/beam also requires the participation of the DU. The DU also needs to refer to the UE history information, so the content of the UE history information needs to be added to the UE CONTEXT SETUP REQUEST message sent by the CU to the DU.

In the case of a multi-connection scenario, when the SN is a CUDU architecture, since the CellGroupConfig information is generated by the DU, that is, DU participation is also required for PSCell/SCell/beam selection. The DU also needs to refer to the UE history information, so the UE history information content needs to be added to the UECONTEXT SETUP REQUEST message sent by the CU to the DU.

Furthermore, in LTE systems, UE history information may be used as a decision to handover ping-pong. In the NR system, SN/beam/SCell related information is added to UE historical information and can be used for judging the ping-pong situation of the PSCell/SCell. When PSCell/SCell selection is carried out, the ping-pong situation is prevented from happening again. For example, the UE history information content is shown in the following table:

from the above table, it can be seen that the situation that the primary cell a is not changed and the primary and secondary cells have B-C-B changes, and the access time of the primary and secondary cells C in the node 2 is determined, and if the access time is less than a predetermined value, the ping-pong phenomenon can be determined. The solution is that the master node adjusts the measurement correlation threshold and improves the selection standard of selecting the master and auxiliary cells C.

In the prior art, through analysis of a Key Performance Indicator (KPI) of an external field network, KPI (Key Performance Indicator) is often concentrated to some weak coverage and high-load places, and a problem is caused each time a terminal moves to the places. In this embodiment, by referring to the content of the UE history information, when the optimal SN/SCell/beam selection is performed, the above problems of coverage, load, and the like can be found in time, the success rate of selecting the optimal SN/SCell/beam is improved, and the user experience is improved.

Fig. 13 is a schematic structural diagram illustrating a UE history information sending apparatus provided in this embodiment, where the apparatus includes: a request message sending module 1301, wherein:

the request message sending module 1301 is configured to send a request message to an SN, where the request message carries first UE history information;

Further, the primary cell information of the SN includes: access time length or cell identification information;

the secondary cell information of the SN includes: access time length or cell identification information;

the cell identification information is a global cell identification code, or a physical cell identification is combined with a frequency point;

the beam information is a beam index used when the current cell is successfully accessed for the first time, or all the beam indexes and access time lengths used in the current cell.

The UE history information sending apparatus described in this embodiment may be configured to execute the foregoing method embodiments, and the principle and technical effect are similar, which are not described herein again.

Fig. 14 shows a schematic structural diagram of a UE history information receiving apparatus provided in this embodiment, where the apparatus includes: a request message receiving module 1401; wherein:

the request message receiving module 1401 is configured to receive a request message sent by an MN, where the request message carries first UE history information;

The UE history information receiving apparatus described in this embodiment may be configured to execute the method embodiments, and the principle and the technical effect are similar, which are not described herein again.

Fig. 15 is a schematic structural diagram illustrating a UE history information sending apparatus provided in this embodiment, where the apparatus includes: modification request message sending means 1501, wherein:

the modification request message sending device 1501 is configured to send a modification request message to an MN, where the modification request message carries second selection information, and the second selection information is indication information of an SN actively selecting a modified cell and/or beam, so that the MN updates first UE history information according to the second selection information;

Fig. 16 is a schematic structural diagram illustrating a UE history information sending apparatus provided in this embodiment, where the apparatus includes: the context setup message sending module 1601, wherein:

the context establishing message sending module 1601 is configured to send a UE context establishing message to a distribution unit DU, where the UE context establishing message carries UE history information;

Further, the primary cell information includes: access time length or cell identification information;

the secondary cell information includes: access time length or cell identification information;

Fig. 17 is a schematic structural diagram of a UE history information receiving apparatus provided in this embodiment, where the apparatus includes: a context setup message receiving module 1701 and a cell and beam selection module 1702, wherein:

the context establishment message receiving module 1701 is configured to receive a UE context establishment message sent by a central unit CU, where the UE context establishment message carries UE history information;

the cell and beam selection module 1702 is configured to select a corresponding cell and/or beam according to the UE context setup message, obtain a selection result, and send the selection result to the CU;

Referring to fig. 18, the MN includes: a processor (processor)1801, a memory (memory)1802, and a bus 1803;

wherein, the first and the second end of the pipe are connected with each other,

the processor 1801 and the memory 1802 communicate with each other via the bus 1803;

the processor 1801 is configured to call program instructions in the memory 1802 to perform the following steps:

Further, the processor 1801 executes the program to further perform:

receiving a request response message returned by the SN, wherein the request response message carries first selection information, and the first selection information is indication information of a cell and/or a wave beam selected by the SN according to the request message; or the like, or, alternatively,

and receiving a modification request message sent by the SN, wherein the modification request message carries second selection information, and the second selection information is indication information of a cell and/or a beam actively selected and modified by the SN.

Further, the processor 1801 executes the program to further perform:

updating the first UE history information according to the first selection information or the second selection information; and/or the presence of a gas in the atmosphere,

Further, the request message carries indication information for adding, deleting or modifying the cell and/or the beam under the SN.

Further, the processor 1801 executes the program to further perform:

and selecting the SN according to the first UE historical information.

The MN described in this embodiment may be configured to execute the corresponding method embodiments, and the principle and technical effect are similar, which are not described herein again.

Referring to fig. 19, the SN includes: a processor (processor)1901, a memory (memory)1902, and a bus 1903;

the processor 1901 and the memory 1902 communicate with each other via the bus 1903;

the processor 1901 is configured to call program instructions in the memory 1902 to perform the following steps:

Further, the processor 1901 executes the program to perform:

Further, the request message carries indication information for adding, deleting or modifying the cell and/or the beam under the SN;

Further, the processor 1901 executes the program to perform:

The SN described in this embodiment may be used to implement the corresponding method embodiment, and the principle and technical effect are similar, which are not described herein again.

Referring to fig. 20, the SN includes: a processor (processor)2001, a memory (memory)2002, and a bus 2003;

wherein the content of the first and second substances,

the processor 2001 and the memory 2002 communicate with each other via the bus 2003;

the processor 2001 is configured to call the program instructions in the memory 2002 to perform the following steps:

In this embodiment, when the SN modification request message is actively triggered by the SN, the modification request message carries selection information of a cell and/or a beam, so as to notify the MN of the current SN configuration, thereby facilitating the MN to maintain local UE history information.

Referring to fig. 21, the CU includes: a processor (processor)2101, a memory (memory)2102, and a bus 2103;

wherein the content of the first and second substances,

the processor 2101 and the memory 2102 communicate with each other via the bus 2103;

the processor 2101 is configured to invoke program instructions in the memory 2102 to perform the following steps:

Further, the processor 2101 executes the program to perform the following steps:

and updating the UE historical information according to the selection result.

The CU described in this embodiment may be used to implement the corresponding method embodiments described above, and the principle and technical effect are similar, which are not described herein again.

Referring to fig. 22, the DU includes: a processor (processor)2201, a memory 2202, and a bus 2203;

the processor 2201 and the memory 2202 are communicated with each other through the bus 2203;

the processor 2201 is configured to call program instructions in the memory 2202 to perform the following steps:

The DU described in this embodiment may be used to implement the corresponding method embodiment, and the principle and technical effect are similar, which are not described herein again.

The present embodiments disclose a computer program product comprising a computer program stored on a non-transitory computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, enable the computer to perform the methods provided by the above-described method embodiments.

The present embodiments provide a non-transitory computer-readable storage medium storing computer instructions that cause the computer to perform the methods provided by the method embodiments described above.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware. With this understanding in mind, the above-described technical solutions may be embodied in the form of a software product, which can be stored in a computer-readable storage medium such as ROM/RAM, magnetic disk, optical disk, etc., and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the methods described in the embodiments or some parts of the embodiments.

It should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A method for sending UE history information is characterized by comprising the following steps:

sending a SN adding request message to a Secondary Node (SN), wherein the SN adding request message carries first UE historical information and indication information of a cell under the SN to be added so as to request the SN to select the cell under the SN according to the first UE historical information;

the first UE history information comprises access cell lists of UE, each access cell list comprises main cell identification information and access time length of a main node MN, and the MN corresponds to the main cell identification information and access time length of an SN and beam information of each cell; and the SN corresponding to the MN and the MN is the MN and the SN accessed by the UE simultaneously.

2. The UE history information transmitting method according to claim 1, further comprising:

receiving a request response message returned by the SN, wherein the request response message carries first selection information, and the first selection information is indication information of a cell and/or a beam selected by the SN according to the SN addition request message; or the like, or, alternatively,

receiving a modification request message sent by the SN, wherein the modification request message carries second selection information, and the second selection information is indication information of a cell and/or a beam actively selected and modified by the SN;

and under the condition that the modification request message is an auxiliary node modification request message, taking the moment when the auxiliary node modification request message is received as the effective time of cell addition/modification under the SN.

3. The UE history information transmitting method according to claim 2, further comprising:

4. The method for sending UE history information according to any of claims 1-3, wherein the SN addition request message further carries indication information for adding the SN lower beam.

5. The UE history information transmitting method according to any one of claims 1 to 3,

the method for expressing the cell identification information comprises the following steps: a global cell identification code, or a physical cell identifier is combined with a frequency point;

6. The UE history information sending method according to claim 5, wherein before sending the SN addition request message to the secondary node SN, the method further comprises:

and selecting the SN according to the first UE historical information.

7. A method for receiving UE history information is characterized by comprising the following steps:

receiving a SN addition request message sent by a MN, wherein the SN addition request message carries first UE history information and indication information of a cell under SN addition;

the first UE history information comprises access cell lists of the UE, each access cell list comprises main cell identification information and access time length of a main node MN, and the MN corresponds to the main cell identification information and the access time length of the SN and beam information of each cell; the corresponding SNs of the MN and the MN are the SNs and the MNs accessed by the UE simultaneously;

and selecting the cell under the SN according to the first UE historical information.

8. The UE history information receiving method according to claim 7, wherein the UE history information receiving method further comprises:

and returning a request response message to the MN according to the SN addition request message, wherein the request response message carries first selection information, and the first selection information is indication information of a cell and/or a beam selected by the SN according to the SN addition request message.

9. The UE history information receiving method according to claim 8, wherein the SN addition request message further carries indication information for adding the SN lower beam;

10. The method for receiving the historical information of the UE according to any of claims 7-9, wherein the cell identification information is a global cell identity, or a physical cell identity is combined with a frequency point;

11. A method for sending UE history information is characterized by comprising the following steps:

sending a modification request message to an MN, wherein the modification request message carries second selection information, the second selection information is indication information of an SN actively selecting a modified cell and/or beam, so that the MN updates the history information of first UE according to the second selection information, and under the condition that the modification request message is an auxiliary node modification request message, the time of receiving the auxiliary node modification request message is taken as the effective time of cell addition/modification under the SN;

the first UE history information comprises access cell lists of the UE, each access cell list comprises main cell identification information and access time length of a main node MN, and the MN corresponds to the main cell identification information and the access time length of the SN and beam information of each cell; and the MN and the SN corresponding to the MN are the MN and the SN accessed by the UE at the same time.

12. The UE history information sending method according to claim 11, wherein the cell identifier information is a global cell identifier, or a combination of a physical cell identifier and a frequency point;

13. A method for sending UE history information is characterized by comprising the following steps:

sending a UE context establishment message to a Distribution Unit (DU), wherein the UE context establishment message carries UE historical information so as to request the DU to select a corresponding cell according to the UE context establishment message;

the UE history information comprises access cell lists of the UE, each access cell list comprises main cell identification information and access time length of a main node MN, and the MN corresponds to the main cell identification information and the access time length of an SN (service number), and beam information of each cell; and the MN and the SN corresponding to the MN are the MN and the SN accessed by the UE at the same time.

14. The UE history information transmitting method according to claim 13, further comprising:

and updating the UE historical information according to the selection result.

15. The UE history information sending method according to claim 13 or 14, wherein the cell identification information is a global cell identity, or a physical cell identity is combined with a frequency point;

16. A method for receiving UE history information is characterized by comprising the following steps:

selecting a corresponding cell according to the UE context establishment message to obtain a selection result, and sending the selection result to the CU;

the UE history information comprises access cell lists of the UE, each access cell list comprises main cell identification information and access time length of a main node MN, and the main cell identification information and the access time length of the SN corresponding to the MN and beam information of each cell; and the SN corresponding to the MN and the MN is the MN and the SN accessed by the UE simultaneously.

17. The UE history information receiving method according to claim 16, wherein the cell identification information is a global cell identity, or a combination of a physical cell identity and a frequency point;

18. An apparatus for transmitting UE history information, comprising:

a request message sending module, configured to send a SN addition request message to a SN, where the SN addition request message carries first UE history information and indication information of adding the cell under the SN, so as to request the SN to select the cell under the SN according to the first UE history information;

the first UE history information comprises access cell lists of the UE, each access cell list comprises main cell identification information and access time length of a main node MN, and the MN corresponds to the main cell identification information and the access time length of the SN and beam information of each cell; and the SN corresponding to the MN and the MN is the MN and the SN accessed by the UE simultaneously.

19. An apparatus for receiving UE history information, comprising:

a request message receiving module, configured to receive a SN addition request message sent by a MN, where the SN addition request message carries first UE history information and indication information for adding a cell under the SN;

and the selection module is used for selecting the cell under the SN according to the historical information of the first UE.

20. An apparatus for transmitting history information of a UE, comprising:

a modification request message sending device, configured to send a modification request message to an MN, where the modification request message carries second selection information, and the second selection information is indication information of a cell and/or a beam actively selected and modified by an SN, so that the MN updates first UE history information according to the second selection information, and when the modification request message is an auxiliary node modification request message, takes a time at which the auxiliary node modification request message is received as an effective time for cell addition/modification under the SN;

21. An apparatus for transmitting history information of a UE, comprising:

a context establishing message sending module, configured to send a UE context establishing message to a distribution unit DU, where the UE context establishing message carries UE history information to request the DU to select a corresponding cell according to the UE context establishing message;

the UE history information comprises access cell lists of the UE, each access cell list comprises main cell identification information and access time length of a main node MN, and the MN corresponds to the main cell identification information and the access time length of an SN (service number), and beam information of each cell; and the SN corresponding to the MN and the MN is the MN and the SN accessed by the UE simultaneously.

22. An apparatus for receiving UE history information, comprising:

the cell and beam selection module is used for selecting a corresponding cell according to the UE context establishment message to obtain a selection result and sending the selection result to the CU;

23. A MN comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor, when executing the program, performs the steps of:

sending a SN adding request message to an auxiliary node (SN), wherein the SN adding request message carries first UE historical information and indication information of a cell under the SN to be added so as to request the SN to select the cell under the SN according to the first UE historical information;

24. The MN of claim 23, wherein the processor, when executing the program, further performs:

and under the condition that the modification request message is the auxiliary node modification request message, taking the moment when the auxiliary node modification request message is received as the effective time of cell addition/modification under the SN.

25. The MN of claim 24, wherein the processor, when executing the program, further performs:

26. The MN according to any of claims 23-25, wherein the SN addition request message further carries indication information for adding the SN down/beam.

27. The MN according to any of claims 23-25, wherein the cell identity information is a global cell identity, or a physical cell identity in combination with a frequency point;

28. The MN of claim 27, wherein the processor, when executing the program, further performs:

and selecting the SN according to the first UE historical information.

29. A SN comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor, when executing the program, performs the steps of:

the first UE history information comprises access cell lists of the UE, each access cell list comprises main cell identification information and access time length of a main node MN, and the MN corresponds to the main cell identification information and the access time length of the SN and beam information of each cell; the corresponding SNs of the MN and the MN are the SNs and the MNs accessed by the UE at the same time;

30. The SN of claim 29, wherein the processor, when executing the program, further performs:

31. The SN of claim 30, wherein the SN addition request message further carries indication information for adding the SN lower beam;

32. A SN according to any of claims 29-31, wherein the cell identity information is a global cell identity, or a physical cell identity in combination with a frequency point;

33. A SN comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to perform the steps of:

34. The SN of claim 33, wherein the cell id information is a global cell id, or a combination of a physical cell id and a frequency point;

35. A CU comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to perform the steps of:

36. The CU of claim 35, wherein the processor, when executing the program, further performs:

and updating the UE historical information according to the selection result.

37. The CU of claim 35 or claim 36, wherein the cell ID information is a global cell ID or a combination of a physical cell ID and a frequency bin;

38. A DU comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to perform the steps of:

39. The DU of claim 38, wherein the cell id information is a global cell id or a combination of physical cell id and frequency;

40. A non-transitory computer readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the UE history information transmitting method according to any one of claims 1 to 6 and 11 to 15.

41. A non-transitory computer-readable storage medium having stored thereon a computer program, wherein the computer program, when executed by a processor, implements the UE history information receiving method according to any one of claims 7 to 10 and 16 to 17.