CN111148222B

CN111148222B - Paging method, device, system, CU, AMF and storage medium

Info

Publication number: CN111148222B
Application number: CN201811303624.5A
Authority: CN
Inventors: 刘爱娟; 汪颖; 王胡成; 孙建成
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2018-11-02
Filing date: 2018-11-02
Publication date: 2021-06-29
Anticipated expiration: 2038-11-02
Also published as: WO2020088618A1; CN111148222A

Abstract

The invention discloses a paging method, a paging device, a paging system, a CU, an AMF and a storage medium, which are used for solving the problem that repeated paging can not be carried out in a CU/DU separation mode in the prior art. The method comprises the following steps: a central unit CU receives a first paging message sent by a core network AMF, wherein the first paging message carries information of a first Discontinuous Reception (DRX) cycle of a terminal UE to be paged; according to the first paging message, sending information of a first DRX period of the UE to each distributed unit DU, and enabling each DU to page the UE; and if the CU determines that a target DU for second paging exists, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after a target DRX period corresponding to the target DU.

Description

Paging method, device, system, CU, AMF and storage medium

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a paging method, apparatus, system, CU, AMF, and storage medium.

Background

In an LTE system, a 4G mobile telecommunications radio network (E-UTRAN) consists of a number of 4G base stations (enodebs), wherein the enodebs are connected to a 4G core network (EPC) via an S1 interface and the enodebs are connected to each other via an X2 interface. When studying 5G systems, it is considered that a Central Unit (CU) is introduced for centralized control and scheduling, the Radio Resource Control (RRC) function of the base station and part of the layer 2 or/and layer 1 functions are at the Central node, and other functions of the base station are deployed on a Distributed Unit (DU).

Existing paging mechanisms take into account power saving, and the terminal (UE) adopts the principle of Discontinuous Reception (DRX) when receiving a paging message. Each 5G base station (gNB) informs the DRX period of the 5G core network (AMF) when the interface is established with the AMF, and all cells under one gNB adopt the same DRX period. The UE also informs the AMF of the DRX period of the UE, the AMF sends the UE-specific DRX period to the base station, and the base station selects a minimum value from the default DRX period and the UE-specific DRX period supported by the base station as the paging DRX period of the UE. If the AMF does not receive the response of the UE after sending a paging message to the gNB, the AMF continues to send the paging message on the NG interface. The time interval between two paging is the paging DRX cycle that needs to be considered for the UE. However, in the CU/DU separation mode, a CU may connect to many DUs, each DU may configure a different DRX cycle, and according to the above paging mechanism, the base station can only report a default DRX cycle of the base station itself, and the current specification cannot support repeated paging in the separation mode.

Therefore, in the CU/DU separation mode, how to perform repeated paging to effectively page the UE is an urgent problem to be solved.

Disclosure of Invention

The embodiment of the invention provides a paging method, a paging device, a paging system, a CU, an AMF and a storage medium, which are used for solving the problem that repeated paging can not be carried out in a CU/DU separation mode in the prior art.

The embodiment of the invention provides a paging method, which is applied to a CU, and comprises the following steps:

a central unit CU receives a first paging message sent by a core network AMF, wherein the first paging message carries information of a first Discontinuous Reception (DRX) cycle of a terminal UE to be paged;

according to the first paging message, sending information of a first DRX period of the UE to each distributed unit DU, and enabling each DU to page the UE;

and if the CU determines that a target DU for second paging exists, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after a target DRX period corresponding to the target DU.

Further, before receiving the first paging message sent by the AMF, the method further includes:

receiving information of a second DRX period supported by each DU transmitted by each DU connected with the CU;

and generating a DRX cycle list for each DU according to the received information of each second DRX cycle.

Further, the determining that there is a target DU for the second paging includes:

for each DU, judging whether a paging response of the UE is received after the target DRX cycle duration corresponding to the DU is received according to the second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list;

if not, the DU is determined as the target DU.

Further, the method further comprises:

and if the CU receives the paging response of the UE, sending first prompt information of successful paging of at least one existing DU to the AMF, and enabling the AMF to send second prompt information for stopping paging to other CUs according to the first prompt information.

Further, the method further comprises:

and receiving second prompt information of stopping paging sent by the AMF, and informing each DU connected with the AMF to stop paging.

generating a DRX period list aiming at each DU according to the received information of each second DRX period;

and sending the DRX cycle list to the AMF and storing the DRX cycle list.

and if a second paging message which is sent by the AMF and aims at the target DU is received, determining that the target DU for second paging exists, wherein the second paging message is sent when the AMF judges that the paging response of the UE is not received after the target DRX cycle duration corresponding to the target DU.

The embodiment of the invention also provides a paging method applied to AMF, which comprises the following steps:

the AMF receives information of a first DRX period of UE to be paged, and determines a target CU according to the position information of the UE;

and sending a first paging message to the target CU, wherein the first paging message carries the information of the first DRX period.

Further, before sending the first paging message to the target CU, the method further comprises:

and receiving and storing the DRX period list sent by the CU.

Further, the method further comprises:

if not, a second paging message is sent to the CU.

Further, the method further comprises:

receiving first prompt information sent by a first target CU, wherein the first prompt information is sent when the first target CU judges that at least one DU paging is successful;

and sending second prompt information for stopping paging to second target CUs except the first target CU in the target CUs according to the first prompt information.

An embodiment of the present invention further provides a CU, where the CU includes a memory, a processor, and a transceiver:

the processor is configured to receive a first paging message sent by a core network AMF, where the first paging message carries information of a first discontinuous reception DRX cycle of a terminal UE to be paged; according to the first paging message, sending information of a first DRX period of the UE to each distributed unit DU, and enabling each DU to page the UE; if the target DU for second paging is determined to exist, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after the target DRX period corresponding to the target DU;

the transceiver is configured to receive a first paging message sent by a core network AMF under the control of the processor, and send information of a first DRX cycle of the UE to each distributed unit DU.

Further, the processor is configured to receive information of a second DRX cycle supported by each DU transmitted by each DU; and generating a DRX cycle list for each DU according to the received information of each second DRX cycle.

Further, the processor is configured to determine, for each DU, whether to receive a paging response of the UE after a target DRX cycle duration corresponding to the DU is determined according to a second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list; if not, the DU is determined as the target DU.

Further, the processor is configured to send, if a paging response of the UE is received, first prompt information that at least one DU exists and paging is successful to the AMF, so that the AMF sends, according to the first prompt information, second prompt information to stop paging to other CUs.

Further, the processor is configured to receive information of a second DRX cycle supported by each DU transmitted by each DU connected to the CU; generating a DRX period list aiming at each DU according to the received information of each second DRX period; and sending the DRX cycle list to the AMF and storing the DRX cycle list.

Further, the processor is configured to determine that a target DU for performing a second paging exists if a second paging message for the target DU and sent by the AMF is received, where the second paging message is sent when the AMF determines that a paging response of the UE is not received after the target DRX cycle duration corresponding to the target DU.

Further, the processor is configured to receive a second prompt message for stopping paging sent by the AMF, and notify each DU connected to the processor of stopping paging.

An embodiment of the present invention further provides an AMF, where the AMF includes a memory, a processor, and a transceiver:

the processor is used for receiving information of a first DRX period of UE to be paged and determining a target CU according to the position information of the UE; sending a first paging message to the target CU, wherein the first paging message carries the information of the first DRX period;

the transceiver is configured to receive information of a first DRX cycle of a UE to be paged, and send a first paging message to the target CU.

Further, the processor is configured to receive and store a DRX cycle list sent by the CU.

Further, the processor is configured to determine, for each DU, whether to receive a paging response of the UE after a target DRX cycle duration corresponding to the DU is determined according to a second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list; if not, a second paging message is sent to the CU.

Further, the processor is configured to receive first prompt information sent by a first target CU, where the first prompt information is sent by the first target CU when the first target CU determines that at least one DU is successfully paged; and sending second prompt information for stopping paging to second target CUs except the first target CU in the target CUs according to the first prompt information.

The embodiment of the invention provides a paging device, which is applied to a CU, and comprises:

a first receiving module, configured to receive a first paging message sent by a core network AMF, where the first paging message carries information of a first discontinuous reception DRX cycle of a terminal UE to be paged;

a first sending module, configured to send information of a first DRX cycle of the UE to each distributed unit DU according to the first paging message, so that each DU pages the UE;

a determining module, configured to send a second paging message for the target DU to the target DU if it is determined that a target DU for performing a second paging exists, where the target DU is a target DU for which a paging response is not received after a target DRX cycle corresponding to the target DU.

The embodiment of the invention provides a paging device, which is applied to AMF, and the device comprises:

the second receiving module is used for receiving the information of the first DRX period of the UE to be paged and determining a target CU according to the position information of the UE;

and a second sending module, configured to send a first paging message to the target CU, where the first paging message carries information of the first DRX cycle.

Embodiments of the present invention also provide a computer-readable storage medium storing a computer program executable by a CU, which when run on the CU, causes the CU to perform the steps of any of the methods described above as applied to the CU.

Embodiments of the present invention also provide a computer-readable storage medium storing a computer program executable by an AMF, which, when running on the AMF, causes the AMF to perform the steps of any of the methods described above as applied to the AMF.

The embodiment of the invention provides a paging system, which comprises a paging device applied to a central unit CU and a paging device applied to a core network AMF.

The embodiment of the invention provides a paging method, a paging device, a paging system, a CU, an AMF and a storage medium, wherein the method comprises the following steps: a central unit CU receives a first paging message sent by a core network AMF, wherein the first paging message carries information of a first Discontinuous Reception (DRX) cycle of a terminal UE to be paged; according to the first paging message, sending information of a first DRX period of the UE to each distributed unit DU, and enabling each DU to page the UE; and if the CU determines that a target DU for second paging exists, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after a target DRX period corresponding to the target DU. In the method, a CU sends a first DRX period of UE to each DU, so that each DU determines a target DRX period according to a second DEX of the DU and the first DRX period, paging is carried out, if a target CU for carrying out second paging is determined according to the target DRX period, paging is determined to be initiated again, the DRX period of paging is determined under a CU/DU separation mode, and the UE can be successfully paged through repeated paging.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1(a) is a schematic diagram of a deployment structure 1 on a 5G radio access network side according to an embodiment of the present invention;

fig. 1(B) is a schematic diagram of a deployment structure 2 on a 5G radio access network side according to an embodiment of the present invention;

fig. 2(a) is a schematic diagram of a 5G LTE control plane protocol stack provided in the embodiment of the present invention;

fig. 2(B) is a schematic diagram of a 5G LTE user plane protocol stack provided in the embodiment of the present invention;

fig. 3 is a schematic diagram illustrating a CU/DU separation method on 8 RAN sides according to an embodiment of the present invention;

fig. 4 is a process diagram of a paging method according to embodiment 1 of the present invention;

fig. 5 is a schematic diagram illustrating a specific process of a paging method according to embodiment 3 of the present invention;

fig. 6 is a process diagram of a paging method according to embodiment 5 of the present invention;

fig. 7 is a schematic diagram illustrating a specific process of a paging method according to embodiment 7 of the present invention;

fig. 8 is a schematic structural diagram of a CU according to embodiment 8 of the present invention;

fig. 9 is a schematic structural diagram of an AMF according to embodiment 8 of the present invention;

fig. 10 is a schematic structural diagram of a paging device according to embodiment 10 of the present invention;

fig. 11 is a schematic structural diagram of a paging device according to embodiment 11 of the present invention;

fig. 12 is a schematic structural diagram of a paging system according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the attached drawings, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1:

in the research process of 5G, the 5G network deployment that may be adopted on the Radio Access Network (RAN) side includes:

deployment structure 1:

fig. 1(a) shows a typical LTE architecture, where there are multiple cells (cells) under an eNB, the eNB and an EPC are connected through an S1 interface, the enbs are connected through an X2 interface, and in a connected state, the UE and the cells perform air interface data transceiving, where the multiple cells use the same DRX cycle.

Deployment structure 2:

as shown in fig. 1(B), the nodes on the network side, i.e., the base stations, are divided into CUs and DUs, and the nodes on the user side are UEs, where one CU can connect multiple DUs. The interface (NG) between the base stations and the core network is terminated in the CU, and the interface (Xn) between the base stations is also terminated in the CU.

Considering that the interface control signaling needs higher reliability, the control plane transport layer adopts Stream Control Transmission Protocol (SCTP), and a specific 5G LTE control plane protocol stack is shown in fig. 2 (a). The user plane mainly considers the protocol specification defined inside the 3GPP and the compatibility with the original system, and uses the GPRS tunneling protocol (GTP-U), and a specific 5G LTE user plane protocol stack is shown in fig. 2 (B).

For the mode of CU/DU separation in the deployment architecture 2, the mode of CU/DU separation on the RAN side needs to be considered, and currently, 8 possibilities are proposed in the research phase, as shown in fig. 3.

Mode 1: a Radio Resource Control (RRC) layer in the CU, a Packet Data Convergence layer (PDCP), a Radio Link Control (RLC), a Media Access Control (MAC) layer and a physical layer, and a Radio Frequency signal Control (RF) layer in the DU;

mode 2: RRC, PDCP in CU, RLC, MAC and physical layer, RF in DU;

mode 3: RRC, PDCP, RLC upper layer in CU, RLC bottom layer, MAC and physical layer, RF in DU;

mode 4: RRC, PDCP, RLC in CU, MAC and physical layer, RF in DU;

mode 5: RRC, PDCP, RLC, MAC upper layer is in CU, MAC bottom layer and physical layer, RF is in DU;

mode 6: RRC, PDCP, RLC, MAC in CU, physical layer, RF in DU;

mode 7: RRC, PDCP, RLC, MAC and part of physical layer are in CU, bottom layer of physical layer and RF is in DU;

mode 8: RRC, PDCP, RLC, MAC and physical layer are in CU, RF is in DU.

Mode 3 is the standardized mode that is decided to be adopted through discussion.

However, in the CU/DU split mode, the existing paging mechanism has not been able to satisfy paging in this mode. Each gNB of the existing paging mechanism will inform the AMF of the DRX cycle when establishing an interface with the AMF, and all cells under one gNB adopt the same DRX cycle. The UE also informs the AMF of the DRX period of the UE, the AMF sends the UE-specific DRX period to the base station, and the base station selects a minimum value from the default DRX period and the UE-specific DRX period supported by the base station as a target paging DRX period of the UE. However, in the CU/DU separation mode, a CU may connect many DUs, each DU may configure a different DRX cycle, and according to the above paging mechanism, the base station can only report a default DRX cycle of the base station itself, so the current specification cannot support paging in the separation mode. To solve the technical problem, the following solutions are proposed in the present application.

Fig. 4 is a schematic process diagram of a paging method according to an embodiment of the present invention, where the process includes the following steps:

s401: and the CU receives a first paging message sent by the AMF, wherein the first paging message carries the information of the first Discontinuous Reception (DRX) cycle of the terminal UE to be paged.

The method provided by the embodiment of the invention is applied to the CU, and in a 5G network deployment structure, the network side is divided into the CU and the DU. In order to ensure availability of the UE, the UE needs to initiate a registration process to the AMF, specifically, in the registration process, the UE sends a specific DXR to the AMF through a Non-Access Stratum (NAS) signaling, enters an idle state after registration is completed, and waits for paging of the AMF.

When the AMF needs to page a certain UE, the target CU for paging is determined according to the position information of the UE, and the target CU can be one or more. After determining the target CU, the AMF sends a first paging message to the target CU, which needs to control each DU to which it is connected to perform this paging since it is the first paging. And in order to enable the DU to successfully initiate paging to the UE, the first paging message carries information of a first DRX cycle of the UE to be paged.

And the CU receives the first paging message and executes corresponding operation according to the first paging message.

S402: and sending the information of the first DRX period of the UE to each DU according to the first paging message, so that each DU pages the UE.

Since the first paging message carries the information of the first DRX cycle of the UE, the CU sends the information of the first DRX cycle to each DU connected to the CU after receiving the first paging message.

After the DU receives the information of the first DRX cycle, a target DRX cycle to be finally used for paging the UE is determined according to the first DRX cycle and a second DRX cycle of the DU. Specifically, as in the existing paging mechanism, the DU selects a minimum value in the second DRX cycle supported by itself and the first DRX cycle of the UE as a target DRX cycle for paging the UE, and pages the UE using the target DRX cycle.

S403: and if the CU determines that a target DU for second paging exists, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after a target DRX period corresponding to the target DU.

If the paging response of the UE aiming at a DU is not received after the target DRX period corresponding to the DU, the initiated first paging is considered to be failed, and at the moment, the second paging is required to be initiated.

And if the CU determines that a target DU which needs to be paged for the second time exists, sending a second paging message to the target DU. The target DU is determined when the paging response for the target DU is not received after the target DRX cycle corresponding to the target DU, and the target DU performs the second paging on the UE according to the second paging message.

In the embodiment of the invention, a CU sends information of a first DRX period of UE to each DU, so that each DU determines a target DRX period according to a second DRX period of the DU and the first DRX period, paging is carried out, if a target CU for carrying out second paging is determined according to the target DRX period, paging is determined to be initiated again, the DRX period of paging is determined under a CU/DU separation mode, and the UE can be successfully paged through repeated paging of the UE.

Example 2:

to ensure that the CU can determine the target DU that needs to be paged for the second time, on the basis of the foregoing embodiment, in an embodiment of the present invention, before receiving the first paging message sent by the AMF, the method further includes:

Since each CU may connect to multiple DUs in the CU/DU separation mode, and each DU may configure a different DRX cycle, to ensure that in this mode, the target DRX cycle for paging may be determined, the CU stores the DRX cycles supported by each DU included in the CU in a list.

Each DU transmits information of second DRX periods supported by the DU to a CU connected with the DU, the CU receives the information of each second DRX period, and a DRX period list aiming at each DU is generated according to the information of each second DRX period. Specifically, the information of each second DRX cycle carries the second DRX cycle of each DU, and in order to identify which DU the each second DRX cycle belongs to, the information also carries the identification information of the DU, where the identification information may be a unique serial number, an IP address, and the like of the DU. And the CU stores the second DRX period of the DU corresponding to the identification information in one-to-one correspondence with the DU of the identification information according to the identification information of each DU, generates a DRX period list aiming at each DU and locally saves the DRX period list.

On the basis of the foregoing embodiments, in an embodiment of the present invention, the determining that there is a target DU for performing the second paging includes:

if not, the DU is determined as the target DU.

The CU generates a DRX cycle list for each DU from the received information of each second DRX cycle and locally saves it. And after receiving the first paging message, controlling all DUs connected with the control unit to initiate a first paging. In order to ensure that the paging for the UE can be successful, after the first paging is initiated, monitoring whether a paging response of the UE is received, if so, considering that the first paging is successful, and if not, considering that the first paging is failed, and initiating the second paging.

And for each DU, determining the target DRX period of the DU according to the locally stored DRX period list, and determining whether the first paging is successful. In order to facilitate whether the CU successfully pages the UE, in the embodiment of the present invention, if the paging of the UE is successful, the UE sends a paging response to the CU. Specifically, the CU may determine, for each DU, a target DRX cycle corresponding to the DU according to the obtained second DRX cycle of the DU and the first DRX cycle of the UE, and determine whether a paging response of the UE is received after the target DRX cycle is ended, if not, determine that the first paging of the DU fails, determine the DU as the target DU, and need to instruct the target DU to initiate a second paging, so as to ensure that the UE can be paged successfully.

In the embodiment of the invention, the CU determines the target DRX period corresponding to the DU according to the second DRX period of the DU in the DRX period list and the first DRX period of the UE, and judges whether the paging response of the UE is received after the target DRX period according to the target DRX period so as to determine whether the DU is the target DU for carrying out the second paging, thereby completing the paging of the UE in a CU/DU separation mode.

Example 3:

in order to ensure that paging of the UE can be stopped immediately after paging is successful for the UE, so as to avoid waste of network resources, on the basis of the foregoing embodiments, in an embodiment of the present invention, the method further includes:

When the AMF pages the UE, it may determine a plurality of target CUs according to the location information of the UE to ensure that the UE can be paged successfully and quickly. Therefore, after the target CU controls the DUs to initiate paging to the UE, if a certain target CU receives a paging response of the UE, it is considered that at least one DU contained in the CU has been paged successfully, and at this time, in order to avoid causing repeated paging and waste of network resources, the target CU needs to send a first prompt message to the AMF to notify the AMF that the UE paging itself is successful. In order to enable the AMF to determine which target CU has been paged successfully, the first prompting message may include identification information of the target CU, specifically, the identification information may be an IP address of the CU, and the like.

After receiving the first prompting message, the AMF may determine that the paging for the UE has been successful, and in order to avoid network resource waste and repeated paging, it needs to send a second prompting message for stopping paging to other target CUs except the target CU, so that the other target CUs stop the paging for the UE.

In order to reduce the waste of network resources, on the basis of the foregoing embodiments, in an embodiment of the present invention, the method further includes:

When the CU receives the second prompt message sent by the AMF, the CU indicates that other CUs have successfully paged the UE, and in order to avoid network resource waste and repeated paging, the CU informs each DU connected with the CU to immediately stop paging the UE.

The above embodiments are described in detail below with reference to a specific embodiment, as shown in fig. 5, including the following steps:

in the CU/DU separation mode, one CU connects 2 DUs, the second DRX cycle length of DU1 is 64ms, and the second DRX cycle length of DU2 is 128 ms.

Step 1: when the base station is connected to the network, both the DU1 and the DU2 report the second DRX cycle supported by the CU to the CU, and the CU generates and stores a DRX cycle list (list) including each DU and the second DRX cycle corresponding to the DU according to the second DRX cycle of each DU.

Step 2: the UE initiates a registration request to the network side. In the registration process, the UE informs the first DRX period of the AMF through NAS signaling, and the UE enters an idle state after the registration is finished and waits for paging of the AMF.

And step 3: the AMF initiates paging to the UE. And determining a target CU according to the position information of the UE, and sending a first paging message to the target CU, wherein the first paging message carries a first DRX period of the UE.

And 4, step 4: after receiving the first paging message, the target CU sends the first DRX cycle of the UE to each DU connected to it.

And 5: DU1 and DU2 both receive the first DRX cycle of the UE, select the minimum value between the first DRX cycle and its own second DRX cycle, determine the minimum value as the target DRX cycle for the UE, and initiate paging to the UE according to the target DRX cycle.

Specifically, the target DRX cycle of DU1 should be no greater than 64, and the target DRX cycle of DU2 should be no greater than 128.

Step 6: the CU determines that the DU1 paging with the second DRX period of 64 is completed according to the self-stored DRX period list, but does not receive the response message of the UE, determines that the DU1 is the target DU at the moment, sends a second paging message to the DU1, wherein the second paging message carries the first DRX period of the UE, and initiates a second paging by the DU 1.

And 7: the CU determines that the second paging of DU1 with the second DRX cycle of 64 has been completed according to the self-stored DRX cycle list, and since the second DRX cycle of DU2 is 128, which is the time when DU1 can complete two paging, the first paging of DU2 with the second DRX cycle of 128 has also been completed at this time, but no paging response of the UE is received, the CU sends a second paging message to DU2 and DU1, and DU2 and DU1 initiate a third paging at the same time.

And 8: and the CU receives the paging response of the UE and sends first prompt information that at least one DU paging is successful to the AMF.

And step 9: and the AMF receives the first paging message, and sends second prompt information for stopping paging to other CUs so that the other CUs stop sending paging messages.

The method does not need to report the DRX period of the CU to the AMF, but aims at the existing specification that the DRX period is a value which is necessarily provided for the AMF, the DRX period is carried when the CU sends the Paging message to the AMF, and the CU does not need to send the DRX period of the CU in the scheme, so that the CU does not need to carry the DRX period when sending the Paging message to the AMF in the scheme, and the original Paging message is changed at the moment, namely the Default Paging DRX period is changed from M to O, as shown in the table 1.

TABLE 1

In the embodiment of the invention, the CU controls other CUs to stop paging by sending the first prompt message that at least one DU has been successfully paged to the AMF, thereby avoiding the situations of resource waste and repeated paging.

Example 4:

in order to enable the AMF to determine the target DU when the second paging is required, on the basis of the foregoing embodiments, in an embodiment of the present invention, before receiving the first paging message sent by the AMF, the method further includes:

and sending the DRX cycle list to the AMF and storing the DRX cycle list.

Since each CU may connect to multiple DUs in the CU/DU separation mode, and each DU may configure a different DRX cycle, to ensure that in this mode, the target DRX cycle for paging may be determined, the CU sends the DRX cycles supported by each DU connected to the CU to the AMF in the form of a list.

In order for a CU to acquire the second DRX period of each DU connected with the CU, each DU transmits information of the second DRX period supported by the CU to the CU connected with the DU, the CU receives the information of each second DRX period, and generates a DRX period list aiming at each DU according to the information of each second DRX period. Specifically, the information of each second DRX cycle carries the second DRX cycle of each DU, and in order to identify which DU the each second DRX cycle belongs to, the information also carries the identification information of the DU, for example, the identification information may be a unique serial number, an IP address, and the like of the DU. And the CU stores the second DRX period of the DU corresponding to the identification information in one-to-one correspondence with the DU of the identification information according to the identification information of each DU, generates a DRX period list aiming at each DU and sends the DRX period list to the AMF, so that the AMF can judge the target DU when the second paging is needed according to the DRX period list.

In the embodiment of the invention, the CU sends the self-supported DRX period list to the AMF, so that the AMF can determine the target DU when the second paging is needed, and further can complete the paging of the UE in a CU/DU separation mode.

After the CU sends the DRX period list supported by the CU to the AMF, the AMF determines a target CU needing to be paged for the second time. When the AMF determines that the paging response of the UE is not received after the target DRX cycle duration corresponding to a DU, the DU is determined to be the target DU, and at this time, a second paging message is sent to the CU, so that the CU can know which DU should be controlled to perform the second paging, where the second paging message includes, in addition to the second DRX cycle of the target DU, identification information of the target DU, and specifically, the identification information of the target DU may be the DRX cycle of the target DU.

When the CU receives the second paging message, the CU determines the target DU according to the identification information of the target DU included in the second paging message, and sends the second paging message to the target DU, so that the target DU initiates a second paging for the UE.

In the embodiment of the invention, the CU determines that the target DU for the second paging exists by receiving the second paging message sent by the AMF.

Example 5:

fig. 6 is a schematic process diagram of a paging method according to an embodiment of the present invention, where the process includes the following steps:

s501: and the AMF receives the information of the first DRX period of the UE to be paged and determines a target CU according to the position information of the UE.

The method provided by the embodiment of the invention is applied to the AMF, when the UE needs to register to access the network, the UE sends the information of the specific first DRX period to the AMF through NAS signaling, and the UE goes to an idle state after the registration is finished and waits for the paging of the AMF.

After receiving the information of the first DRX cycle of the UE to be paged, the AMF may determine the location of the UE, determine a CU covering the location area according to the location information, and use the CU as a target CU, and may specifically determine one or more target CUs to ensure that the UE can be paged successfully and quickly.

S502: and sending a first paging message to the target CU, wherein the first paging message carries the information of the first DRX period.

When the AMF needs to initiate paging to the UE, a first paging message is sent to a target CU corresponding to the UE, and the paging needs the target CU to control all DUs connected with the target CU to page because the paging is carried out for the first time. In order to enable the DU to successfully initiate paging for the UE, the first paging message carries a first DRX cycle of the UE, and the DU is enabled to determine a target DRX cycle according to the first DRX cycle and a second DRX cycle of the DU itself, thereby implementing paging for the UE.

In the embodiment of the invention, the CU is controlled to initiate the paging of the UE by sending the first paging message to the CU, so that the UE is effectively paged in a CU/DU separation mode.

Example 6:

in order to determine whether to initiate the second paging, on the basis of the foregoing embodiments, in an embodiment of the present invention, before sending the first paging message to the target CU, the method further includes:

and receiving and storing the DRX period list sent by the CU.

And in order to determine the target DU for the second paging, on the basis of the foregoing embodiments, the method further includes:

if not, a second paging message is sent to the CU.

When receiving the DRX period list which is transmitted by the CU and supported by the CU, the AMF receives the DRX period list and saves the DRX period list.

In order to facilitate the AMF to determine whether paging of the UE is successful, in the embodiment of the present invention, if paging of the UE is successful, the UE sends a paging response to the AMF. And after initiating the first paging, the AMF monitors whether a paging response of the UE is received, if so, the AMF considers that the first paging is successful, and if not, the AMF considers that the first paging is failed and needs to initiate the second paging.

And for each DU, determining the target DRX period of the DU according to the locally stored DRX period list, and determining whether the first paging is successful. Specifically, for each DU, the AMF determines a target DRX cycle corresponding to the DU according to the obtained second DRX cycle of the DU and the first DRX cycle of the UE, and determines whether a paging response of the UE is received after the target DRX cycle is ended, if not, the AMF determines that the first paging of the DU fails, determines the DU as the target DU, and needs to instruct the target DU to initiate a second paging, so as to ensure that the UE can be paged successfully.

In the embodiment of the invention, the AMF determines the target DRX period corresponding to the DU according to the second DRX period of the DU in the DRX period list and the first DRX period of the UE, and judges whether the paging response of the UE is received after the target DRX period according to the target DRX period to determine whether the DU is the target DU for carrying out the second paging, thereby completing the paging of the UE in a CU/DU separation mode.

Example 7:

to avoid the waste of network resources and the occurrence of repeated paging, on the basis of the foregoing embodiments, in the embodiment of the present invention, the method further includes:

When the AMF pages the UE, it may determine a plurality of target CUs according to the location information of the UE to ensure that the UE can be paged successfully and quickly. In order to avoid paging repetition and waste of network resources, if a first target CU in the target CUs determines that at least one DU connected to the first target CU is successfully paged, the first target CU sends first prompt information to the AMF to notify the AMF that the UE is successfully paged by the first target CU. In order to enable the AMF to determine which target CU has been paged successfully, the first indication may include identification information of the first target CU, specifically, the identification information may be an IP address of the first target CU, and the like.

After receiving the first prompt message, the AMF may determine that the paging for the UE has succeeded, determine which target CU has completed the paging according to the identification information of the first target CU in the first prompt message, and send a second prompt message to other second target CUs except the first target CU at this time, so that the other second target CUs stop the paging for the UE, thereby avoiding the waste of network resources and the occurrence of repeated paging.

In the embodiment of the invention, the first prompt information sent by the CU is received to determine which target CU finishes paging, so that the second prompt information is sent to other target CUs to stop paging, and the waste of network resources and the situation of repeated paging are avoided.

The above embodiments are described in detail below with reference to a specific embodiment, as shown in fig. 7, including the following steps:

in the CU/DU separation mode, one CU connects 2 DUs, the second DRX cycle of DU1 is 64ms, and the second DRX cycle of DU2 is 128 ms.

Step 1: when the base station is connected to the network, both the DU1 and the DU2 report the second DRX period supported by the CU to the CU, and the CU generates a DRX period list (list) containing each DU and the second DRX period corresponding to the DU according to the second DRX period of each DU and reports the DRX period list supported by the CU to the AMF.

Step 2: the UE initiates a registration request to the network side. In the registration process, the UE informs the AMF of a specific first DRX period through NAS signaling, and the UE enters an idle state after the registration is finished and waits for the paging of the AMF.

And step 3: the AMF initiates paging to the UE. And determining a target CU according to the position information of the UE, and sending a first paging message to the target CU, wherein the first paging message carries a second DRX period of all DUs needing paging and a first DRX period of the UE due to the first paging.

Step 6: the AMF determines that the paging of DU1 with the second DRX cycle of 64 has been completed according to the self-maintained DRX cycle list, but does not receive the response message of the UE, and initiates a second paging for DU 1. And sending a second paging message to the CU, wherein the second paging message only comprises a second DRX period of 64.

And 7: the CU determines that DU1 with the second DRX period of 64 is the target DU according to the second paging message, sends the second paging message to DU1, and initiates the second paging by DU 1.

And 8: the AMF determines that the second paging of DU1 with the second DRX cycle of 64 has been completed according to the self-stored DRX cycle list, and since the second DRX cycle of DU2 is 128, which is the time when DU1 can complete two paging, the first paging of DU2 with the second DRX cycle of 128 has also been completed, but no response message of the UE has yet been received, and sends a third paging message to the CU, where the third paging message includes the second DRX cycles of 64 and 128.

And step 9: the CU determines that DU1 and DU2 with the second DRX periods of 64 and 128 are target DUs according to the third paging message, sends the third paging message to DU1 and DU2, and initiates paging by DU1 and DU 2.

In the CU/DU separation mode, the CU sends a paging message to the AMF as shown in table 1. The existing specification is that the base station sends one DRX period to the AMF, a plurality of DUs are connected below the CU in the scheme, each DU is configured with a different DRX period, at the moment, when the CU sends a Paging message to the AMF, the CU carries a plurality of DRX periods, namely a DRX period list generated by the CU, and therefore the modification of the existing specification is to modify the Default Paging DRX period into the Default Paging DRX period list.

TABLE 2

In addition, in the CU/DU separation mode, the paging message sent by the AMF to the CU is shown in table 3, where the AMF carries all DRX cycles of the DUs that are paged, that is, a DRX cycle list, when initiating the first paging, the AMF determines the target DU according to the stored DRX cycle list for each subsequent paging, and at this time, the retransmitted paging message only needs to carry the DRX cycle of the target DU. However, in the existing specification, the base station has only one DRX cycle and does not have this step, so the modification of the existing specification is: the paging message page sent by the AMF to the CU is added with the DRX cycle list for the target DU.

TABLE 3

Example 8:

fig. 8 is a CU according to an embodiment of the present invention, where the CU includes: a memory, a processor, and a transceiver;

the processor is used for reading the program in the memory and executing the following processes:

receiving a first paging message sent by a core network AMF, wherein the first paging message carries information of a first Discontinuous Reception (DRX) cycle of a terminal UE to be paged;

if the target DU for second paging is determined to exist, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after the target DRX period corresponding to the target DU;

The processor is configured to receive information of a second DRX cycle supported by each DU transmitted by each DU connected to the CU; and generating a DRX cycle list for each DU according to the received information of each second DRX cycle.

The processor is configured to determine, for each DU, whether to receive a paging response of the UE after a target DRX cycle duration corresponding to the DU is received according to a second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list; if not, the DU is determined as the target DU.

And the processor is configured to send, if a paging response of the UE is received, first prompt information that at least one DU exists and paging is successful to the AMF, so that the AMF sends, according to the first prompt information, second prompt information to stop paging to other CUs.

And the processor is used for receiving second prompt information of stopping paging sent by the AMF and informing each DU connected with the processor of stopping paging.

The processor is configured to receive information of a second DRX cycle supported by each DU transmitted by each DU connected to the CU; generating a DRX period list aiming at each DU according to the received information of each second DRX period; and sending the DRX cycle list to the AMF and storing the DRX cycle list.

The processor is configured to determine that a target DU for performing second paging exists if a second paging message for the target DU and sent by the AMF is received, where the second paging message is sent when the AMF determines that a paging response of the UE is not received after a target DRX cycle duration corresponding to the target DU.

Example 9:

fig. 9 is an AMF according to an embodiment of the present invention, where the AMF includes: a memory, a processor, and a transceiver;

the method comprises the steps of receiving information of a first DRX period of UE to be paged, and determining a target CU according to the position information of the UE; sending a first paging message to the target CU, wherein the first paging message carries the information of the first DRX period;

And the processor is used for receiving and storing the DRX cycle list sent by the CU.

The processor is configured to determine, for each DU, whether to receive a paging response of the UE after a target DRX cycle duration corresponding to the DU is received according to a second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list; if not, a second paging message is sent to the CU.

The processor is configured to receive first prompt information sent by a first target CU, where the first prompt information is sent by the first target CU when the first target CU determines that at least one DU paging is successful; and sending second prompt information for stopping paging to second target CUs except the first target CU in the target CUs according to the first prompt information.

Example 10:

based on the same technical concept, the embodiment of the invention provides a paging device which is applied to a CU. As shown in fig. 10, the apparatus provided in the embodiment of the present invention includes:

a first receiving module 1001, configured to receive a first paging message sent by a core network AMF, where the first paging message carries information of a first discontinuous reception DRX cycle of a terminal UE to be paged;

a first sending module 1002, configured to send, according to the first paging message, information of a first DRX cycle of the UE to each distributed unit DU, so that each DU pages the UE;

a determining module 1003, configured to send a second paging message for the target DU to the target DU if it is determined that a target DU for performing a second paging exists, where the target DU is a target DU for which a paging response is not received after a target DRX cycle corresponding to the target DU.

Further, the first receiving module 1001 is further configured to receive information of a second DRX cycle supported by each DU sent by each DU connected to the CU; and generating a DRX cycle list for each DU according to the received information of each second DRX cycle.

Further, the determining module 1003 is specifically configured to, for each DU, determine, according to the second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list, whether to receive a paging response of the UE after the target DRX cycle duration corresponding to the DU is reached; if not, the DU is determined as the target DU.

Further, the first sending module 1002 is further configured to, if the CU receives a paging response of the UE, send, to the AMF, first prompt information that at least one DU exists for paging successfully, so that the AMF sends, according to the first prompt information, second prompt information for stopping paging to another CU.

Further, the first receiving module 1001 is further configured to receive second prompt information for stopping paging sent by the AMF, and notify each DU connected to itself to stop paging.

Further, the first receiving module 1001 is further configured to receive information of a second DRX cycle supported by each DU sent by each DU connected to the CU; generating a DRX period list aiming at each DU according to the received information of each second DRX period;

the first sending module 1002 is further configured to send the DRX cycle list to the AMF and store the DRX cycle list.

Further, the determining module 1003 is specifically configured to determine that there is a target DU for performing second paging if a second paging message, which is sent by the AMF and is specific to the target DU, is received, where the second paging message is sent when the AMF determines that a paging response of the UE is not received after the target DRX cycle duration corresponding to the target DU is received.

Example 11:

based on the same technical concept, the embodiment of the invention provides a paging device which is applied to AMF. As shown in fig. 11, the apparatus provided in the embodiment of the present invention includes:

a second receiving module 1101, configured to receive information of a first DRX cycle of a UE to be paged, and determine a target CU according to location information of the UE;

a second sending module 1102, configured to send a first paging message to the target CU, where the first paging message carries information of the first DRX cycle.

Further, the second receiving module 1101 is further configured to receive and store the DRX cycle list sent by the CU.

Further, the second sending module 1102 is further configured to, for each DU, determine, according to the second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list, whether to receive a paging response of the UE after the target DRX cycle duration corresponding to the DU is reached; if not, a second paging message is sent to the CU.

Further, the second receiving module 1101 is further configured to receive a first prompt message sent by a first target CU, where the first prompt message is sent when the first target CU determines that at least one DU paging is successful;

the second sending module 1102 is further configured to send, according to the first prompt message, second prompt messages for stopping paging to second target CUs, other than the first target CU, in the target CUs.

Example 12:

fig. 12 is a schematic structural diagram of a paging system according to an embodiment of the present invention, where the paging includes a central unit CU1201 and a core network AMF 1202. Wherein:

the central unit CU1201 is configured to receive a first paging message sent by a core network AMF, where the first paging message carries information of a first discontinuous reception DRX cycle of a terminal UE to be paged; according to the first paging message, sending information of a first DRX period of the UE to each distributed unit DU, and enabling each DU to page the UE; and if the target DU for second paging is determined to exist, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after the target DRX period corresponding to the target DU.

The core network AMF1202 is configured to receive information of a first DRX cycle of a UE to be paged, and determine a target CU according to location information of the UE; and sending a first paging message to the target CU, wherein the first paging message carries the information of the first DRX period.

In order to solve the problem that repeated paging cannot be performed in a CU/DU separation mode in the prior art, an embodiment of the present invention provides a paging system.

The CU is used for receiving information of a second DRX period supported by each DU transmitted by each DU connected with the CU; and generating a DRX cycle list for each DU according to the received information of each second DRX cycle.

The CU is used for judging whether a paging response of the UE is received after the target DRX period duration corresponding to the DU according to the second DRX period and the first DRX period of the DU, which are stored in the DRX period list, aiming at each DU; if not, the DU is determined as the target DU.

And the CU is used for sending first prompt information of successful paging of at least one existing DU to the AMF if the paging response of the UE is received, so that the AMF sends second prompt information for stopping paging to other CUs according to the first prompt information.

And the CU is used for receiving second prompt information of stopping paging sent by the AMF and informing each DU connected with the CU of stopping paging.

The CU is used for receiving information of a second DRX period supported by each DU transmitted by each DU connected with the CU; generating a DRX period list aiming at each DU according to the received information of each second DRX period; and sending the DRX cycle list to the AMF and storing the DRX cycle list.

And the CU is used for determining that a target DU for second paging exists if a second paging message which is sent by the AMF and aims at the target DU is received, wherein the second paging message is sent when the AMF judges that a paging response of the UE is not received after the target DRX cycle duration corresponding to the target DU.

And the AMF is used for receiving and storing the DRX cycle list sent by the CU.

The AMF is used for judging whether a paging response of the UE is received after the target DRX cycle duration corresponding to each DU according to the second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list; if not, a second paging message is sent to the CU.

The AMF is used for receiving first prompt information sent by a first target CU, wherein the first prompt information is sent when the first target CU judges that at least one DU paging is successful; and sending second prompt information for stopping paging to second target CUs except the first target CU in the target CUs according to the first prompt information.

Example 13:

on the basis of the foregoing embodiments, an embodiment of the present invention further provides a computer-readable storage medium, in which a computer program executable by an electronic device is stored, and when the program is run on the electronic device, the electronic device is caused to execute the following steps:

the memory having stored therein a computer program that, when executed by the processor, causes the processor to perform the steps of:

and if the target DU for second paging is determined to exist, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after the target DRX period corresponding to the target DU.

Further, the processor receives information of a second DRX cycle supported by each DU transmitted by each DU connected to the CU; and generating a DRX cycle list for each DU according to the received information of each second DRX cycle.

Further, the processor determines, for each DU, whether to receive a paging response of the UE after a target DRX cycle duration corresponding to the DU is received according to a second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list; if not, the DU is determined as the target DU.

Further, if receiving a paging response of the UE, the processor sends first prompt information that at least one DU exists for paging successfully to the AMF, so that the AMF sends second prompt information for stopping paging to other CUs according to the first prompt information.

Further, the processor receives a second prompt message for stopping paging sent by the AMF, and notifies each DU connected to itself to stop paging.

Further, the processor receives information of a second DRX cycle supported by each DU transmitted by each DU connected to the CU; generating a DRX period list aiming at each DU according to the received information of each second DRX period; and sending the DRX cycle list to the AMF and storing the DRX cycle list.

Further, if receiving a second paging message for the target DU sent by the AMF, the processor determines that a target DU for performing a second paging exists, where the second paging message is sent when the AMF determines that a paging response of the UE is not received after the target DRX cycle duration corresponding to the target DU.

The computer readable storage medium may be any available medium or data storage device that can be accessed by a processor in an electronic device, including but not limited to magnetic memory such as floppy disks, hard disks, magnetic tape, magneto-optical disks (MOs), etc., optical memory such as CDs, DVDs, BDs, HVDs, etc., and semiconductor memory such as ROMs, EPROMs, EEPROMs, non-volatile memory (NAND FLASH), Solid State Disks (SSDs), etc.

Example 14:

receiving information of a first DRX period of UE to be paged, and determining a target CU according to the position information of the UE;

Further, the processor receives and stores the DRX cycle list sent by the CU.

Further, the processor determines, for each DU, whether to receive a paging response of the UE after a target DRX cycle duration corresponding to the DU is received according to a second DRX cycle of the DU and the first DRX cycle stored in the DRX cycle list; if not, a second paging message is sent to the CU.

Further, the processor receives first prompt information sent by a first target CU, where the first prompt information is sent when the first target CU determines that at least one DU paging is successful; and sending second prompt information for stopping paging to second target CUs except the first target CU in the target CUs according to the first prompt information.

In summary, the present invention provides a paging method, apparatus, system, CU, AMF and storage medium to solve the problem in the prior art that repeated paging cannot be performed in CU/DU separation mode. The method comprises the following steps: a central unit CU receives a first paging message sent by a core network AMF, wherein the first paging message carries information of a first Discontinuous Reception (DRX) cycle of a terminal UE to be paged; according to the first paging message, sending information of a first DRX period of the UE to each distributed unit DU, and enabling each DU to page the UE; and if the CU determines that a target DU for second paging exists, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after a target DRX period corresponding to the target DU.

For the system/apparatus embodiments, since they are substantially similar to the method embodiments, the description is relatively simple, and reference may be made to some descriptions of the method embodiments for relevant points.

It is to be noted that, in this document, relational terms such as first and second, and the like are used solely to distinguish one entity or operation from another entity or operation without necessarily requiring or implying any actual such relationship or order between such entities or operations.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely application embodiment, or an embodiment combining application and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A method of paging, the method comprising:

and if the CU determines that a target DU for second paging exists, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is the paging response aiming at the target DU which is not received after the target DRX period duration corresponding to the target DU, and the target DRX period duration is determined according to the first DRX period and a preset second DRX period corresponding to the target DU.

2. The method of claim 1, wherein prior to receiving the first paging message sent by the AMF, the method further comprises:

3. The method of claim 2, wherein the determining that there is a target DU for the second paging comprises:

if not, the DU is determined as the target DU.

4. The method of claim 2, wherein the method further comprises:

5. The method of claim 2, wherein the method further comprises:

6. The method of claim 1, wherein prior to receiving the first paging message sent by the AMF, the method further comprises:

and sending the DRX cycle list to the AMF and storing the DRX cycle list.

7. The method of claim 6, wherein the determining that there is a target DU for the second paging comprises:

8. A method of paging, the method comprising:

sending a first paging message to the target CU, wherein the first paging message carries the information of the first DRX period;

wherein the method further comprises:

9. The method of claim 8, wherein prior to sending the first paging message to the target CU, the method further comprises:

and receiving and storing the DRX period list sent by the CU.

10. The method of claim 9, wherein the method further comprises:

if not, a second paging message is sent to the CU.

11. A CU, comprising a memory, a processor, and a transceiver:

the processor is configured to receive a first paging message sent by a core network AMF, where the first paging message carries information of a first discontinuous reception DRX cycle of a terminal UE to be paged; according to the first paging message, sending information of a first DRX period of the UE to each distributed unit DU, and enabling each DU to page the UE; if a target DU for second paging is determined to exist, sending a second paging message aiming at the target DU to the target DU, wherein the target DU is not received a paging response aiming at the target DU after a target DRX cycle duration corresponding to the target DU is determined, and the target DRX cycle duration is determined according to the first DRX cycle and a preset second DRX cycle corresponding to the target DU;

12. The CU of claim 11, wherein the processor is configured to receive information of a second DRX cycle supported by each DU transmitted by each DU connected to the CU; and generating a DRX cycle list for each DU according to the received information of each second DRX cycle.

13. The CU of claim 12, wherein the processor is configured to determine, for each DU, whether to receive a paging response of the UE after a target DRX cycle duration corresponding to the DU according to the second DRX cycle and the first DRX cycle of the DU stored in the DRX cycle list; if not, the DU is determined as the target DU.

14. The CU of claim 12, wherein the processor is configured to send a first indication to the AMF that the at least one DU present is successfully paged if a paging response from the UE is received, and to cause the AMF to send a second indication to stop paging to other CUs according to the first indication.

15. The CU of claim 11, wherein the processor is configured to receive information of a second DRX cycle supported by each DU transmitted by each DU connected to the CU; generating a DRX period list aiming at each DU according to the received information of each second DRX period; and sending the DRX cycle list to the AMF and storing the DRX cycle list.

16. The CU of claim 15, wherein the processor is configured to determine that a target DU for a second paging exists if a second paging message for the target DU sent by an AMF is received, and the second paging message is sent when the AMF determines that a paging response of the UE is not received after a target DRX cycle duration corresponding to the target DU.

17. The CU of claim 12, wherein the processor is configured to receive a second notification message sent by the AMF to stop paging, and to notify each DU connected to itself to stop paging.

18. An AMF, comprising a memory, a processor, and a transceiver:

the transceiver is used for receiving information of a first DRX period of UE to be paged and sending a first paging message to the target CU;

19. The AMF of claim 18, wherein the processor is configured to receive and maintain a list of DRX cycles sent by CUs.

20. The AMF of claim 19, wherein the processor is configured to determine, for each DU, whether to receive a paging response of the UE after a target DRX cycle duration corresponding to the DU according to the second DRX cycle and the first DRX cycle of the DU stored in the DRX cycle list; if not, a second paging message is sent to the CU.

21. An apparatus for paging, the apparatus comprising:

and a determining module, configured to send a second paging message for the target DU to the target DU if it is determined that a target DU for performing a second paging exists, where the target DU is a target DRX cycle duration corresponding to the target DU and a paging response for the target DU is not received, and the target DRX cycle duration is determined according to the first DRX cycle and a preset second DRX cycle corresponding to the target DU.

22. An apparatus for paging, the apparatus comprising:

a second sending module, configured to send a first paging message to the target CU, where the first paging message carries information of the first DRX cycle;

the second receiving module is further configured to receive first prompt information sent by the first target CU, where the first prompt information is sent by the first target CU when the first target CU determines that at least one DU paging is successful;

and the second sending module is further configured to send second prompt information for stopping paging to a second target CU, which is not the first target CU, in the target CU according to the first prompt information.

23. A computer-readable storage medium storing a computer program executable by a CU, the program, when executed on the CU, causing the CU to perform the steps of the method of any one of claims 1-7.

24. A computer-readable storage medium, characterized in that it stores a computer program executable by an AMF, which program, when run on the AMF, causes the AMF to perform the steps of the method according to any one of claims 8-10.

25. A paging system, characterized in that the system comprises paging means applied to a central unit CU according to claim 21, and paging means applied to a core network AMF according to claim 22.