CN116456399A

CN116456399A - Tracking area list construction method and device

Info

Publication number: CN116456399A
Application number: CN202210010820.3A
Authority: CN
Inventors: 段小嫣; 胡博; 陈山枝; 张天同; 高成; 王文慧
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2022-01-06
Filing date: 2022-01-06
Publication date: 2023-07-18

Abstract

A method and device for constructing a tracking area list, the method comprises: constructing a candidate cell set according to the current position and service information of the first user equipment; selecting an optimal serving cell based on the candidate cell set; and determining the service TAL of the first user equipment according to the TAL of the optimal service cell. The invention can reduce the signaling cost of tracking area list update and user paging, and relieve network congestion.

Description

Tracking area list construction method and device

Technical Field

The present invention relates to the field of mobile communications technologies, and in particular, to a method and an apparatus for constructing a tracking area list.

Background

Mobility management is one of the core flows of a mobile communication network, allowing tracking of User Equipments (UEs) and providing communication services in a seamless manner. When the UE detects that it leaves the current registration Area (Registration Area, RA), including a Tracking Area (TA) set in a Tracking Area identity List (TAL), or other conditions are met, the UE reports the new location to the core network by sending a registration update message. If the UE is in idle mode, when new downlink data or signaling arrives, the network will send paging message to the UE, requesting the UE to establish a connection with the network.

Registration area (i.e., tracking area list) management of the network includes assigning and reassigning registration areas to UEs. Typically, the network determines the registration area of the UE based on the UE location and network deployment. Regarding the construction of TAL, specifically, the network side may make decisions on TAL planning using long-term rules based on perceived learning of UE historic location, path, and paging amount, for example: in a time node with high service paging capacity of the UE, TAL with smaller coverage area is distributed to the UE so as to reduce signaling cost generated by paging the UE; for the UE with a repeated route rule, planning the perceived and predicted route serving cell into a TAL so as to reduce the TA updating cost generated by the UE.

When the UE in the idle mode receives the connection request, the core network informs all base stations in RA where the UE is located, and sends paging information to the UE. With the high-density deployment of the radio access network, the coverage of the base station/cell becomes smaller and irregular, and a large amount of signaling needs to be interacted between the network and the UE under the condition of paging a large amount of UEs, so that high signaling overhead is caused, and mobile network resources are wasted. Therefore, a method for constructing a tracking area list is needed to solve the problem of mobility Registration Area (RA) management of the UE in idle mode in the context of high-density deployment of wireless access networks and increased network capacity, so as to reduce signaling overhead and network congestion.

Disclosure of Invention

At least one embodiment of the invention provides a method and equipment for constructing a tracking area list, which can reduce signaling cost and relieve network congestion.

According to one aspect of the present invention, at least one embodiment provides a method for constructing a tracking area list, which is applied to a network function entity, and includes:

constructing a candidate cell set according to the current position and service information of the first user equipment;

selecting an optimal serving cell based on the candidate cell set;

and determining the service TAL of the first user equipment according to the TAL of the optimal service cell.

Furthermore, according to at least one embodiment of the present invention, the constructing a candidate cell set according to the current location and service information of the first user equipment includes:

selecting cells which cover the current position of the first user equipment and meet the service information of the first user equipment to form the candidate cell set.

Furthermore, according to at least one embodiment of the present invention, the selecting an optimal serving cell based on the candidate cell set includes:

predicting a next location of the first user device;

determining the moving direction of the first user equipment according to the current position and the next position of the first user equipment;

And selecting a candidate cell with the smallest included angle with the moving direction from the candidate cell set as an optimal service cell according to the moving direction of the first user equipment.

Furthermore, according to at least one embodiment of the present invention, the determining, according to the TAL to which the optimal serving cell belongs, a serving TAL of the first user equipment includes:

constructing an initial TAL set of the first user equipment, the initial TAL set including at least one TAL;

and determining the service TAL of the first user equipment according to the TAL of the optimal service cell in the initial TAL set.

Furthermore, in accordance with at least one embodiment of the present invention, the constructing the initial TAL set for the first user device includes:

collecting the position information and service information of the first user equipment;

and determining an initial TAL set of the first user equipment meeting a first target according to the collected position information and service information of the first user equipment, wherein the first target is to minimize the number of signaling used for updating and/or paging of a tracking area.

In case the number of the optimal serving cells is greater than one:

if all the optimal service cells belong to the same TAL, determining the TAL to which the optimal service cells belong as the service TAL of the first user equipment;

if all the optimal service cells do not belong to the same TAL, determining the TAL to which the optimal service cell with the coverage meeting the first condition belongs as the service TAL of the first user equipment;

the first condition includes any one of the following: the coverage is maximum; the coverage area is minimum; the coverage is in a first interval.

Furthermore, according to at least one embodiment of the present invention, there is also provided:

determining a candidate service TAL of the first user equipment according to the TAL to which at least one cell in the candidate cell set belongs, wherein the candidate service TAL is different from the service TAL;

and when the first user equipment moves out of the service TAL, taking the candidate service TAL as a new service TAL of the first user equipment.

Furthermore, in accordance with at least one embodiment of the present invention, the candidate service TAL is in the initial TAL set.

Furthermore, in accordance with at least one embodiment of the present invention, the candidate service TAL satisfies a second condition including any one of: the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is greater than a first threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is less than a second threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is in a second interval.

Furthermore, in accordance with at least one embodiment of the present invention, in case the first user equipment moves out of the best serving cell, the method further comprises:

selecting candidate cells except the optimal serving cell from the service TAL of the first user equipment as a new optimal serving cell; or alternatively, the first and second heat exchangers may be,

constructing a new candidate cell set according to the current position and service information of the first user equipment; selecting a new optimal serving cell based on the new candidate cell set; and determining the new service TAL of the first user equipment according to the TAL of the new optimal service cell.

Furthermore, according to at least one embodiment of the present invention, the network function entity is a network data analysis function NWDAF entity and/or a management data analysis function MDAF entity; the method further comprises the steps of:

and the network functional entity sends the information of the service TAL to a mobility management functional entity, and the information of the service TAL is sent to the first user equipment through the mobility management functional entity.

According to another aspect of the present invention, at least one embodiment provides a tracking area list construction apparatus applied to a network function entity, including a memory, a transceiver, and a processor, wherein,

The memory is used for storing a computer program;

the transceiver is used for receiving and transmitting data under the control of the processor;

the processor is configured to read the computer program in the memory and perform the following operations:

selecting an optimal serving cell based on the candidate cell set;

Furthermore, in accordance with at least one embodiment of the present invention, the processor is further configured to read the computer program in the memory and perform the following operations:

predicting a next location of the first user device;

In case the number of the optimal serving cells is greater than one:

Furthermore, according to at least one embodiment of the present invention, the network function entity is a network data analysis function NWDAF entity and/or a management data analysis function MDAF entity;

The processor is further configured to read the computer program in the memory and perform the following operations:

and sending the information of the service TAL to a mobility management functional entity, and sending the information of the service TAL to the first user equipment through the mobility management functional entity.

According to yet another aspect of the present invention, at least one embodiment provides a network functional entity, including:

the construction unit is used for constructing a candidate cell set according to the current position and service information of the first user equipment;

a selecting unit, configured to select an optimal serving cell based on the candidate cell set;

and the determining unit is used for determining the service TAL of the first user equipment according to the TAL of the optimal service cell.

According to another aspect of the invention, at least one embodiment provides a computer-readable storage medium having stored thereon a program which, when executed by a processor, implements the steps of the method as described above.

Compared with the prior art, the method and the device for constructing the tracking area list construct a candidate cell set according to the current position and the service information of the first user equipment, so that an optimal service cell and a service TAL are determined for the first user equipment, the mobile and service characteristics of the user equipment can be met, and updating of the service TAL is reduced. In addition, the embodiment of the invention dynamically constructs the tracking area list along with the movement of the user equipment, and simultaneously considers the updating of the registration area RA (namely the tracking area list TAL) and the paging signaling cost of the user equipment, so that the service TAL can provide high-quality and long-time service for the user equipment.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:

fig. 1 is a schematic diagram of an application scenario according to an embodiment of the present invention;

FIG. 2 is a flowchart of a method for constructing a tracking area list according to an embodiment of the present invention;

FIG. 3 is a flowchart illustrating an exemplary method for constructing a tracking area list according to an embodiment of the present invention;

FIG. 4 is a diagram illustrating interaction between devices in a method for constructing a tracking area list according to an embodiment of the present invention;

FIG. 5 is a diagram illustrating an exemplary initial tracking area provided by an embodiment of the present invention;

fig. 6 is an exemplary diagram of a serving cell and a candidate cell set constructed with a user equipment as a center in an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a network functional entity according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a device for constructing a tracking area list according to an embodiment of the present invention.

Detailed Description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terms first, second and the like in the description and in the claims, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that embodiments of the present application described herein may be capable of operation in sequences other than those illustrated or described herein, for example. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. "and/or" in the specification and claims means at least one of the connected objects.

The techniques described herein are not limited to NR systems and long term evolution (Long Time Evolution, LTE)/LTE evolution (LTE-Advanced, LTE-a) systems and may also be used for various wireless communication systems such as code division multiple access (Code Division Multiple Access, CDMA), time division multiple access (Time Division Multiple Access, TDMA), frequency division multiple access (Frequency Division Multiple Access, FDMA), orthogonal frequency division multiple access (Orthogonal Frequency Division Multiple Access, OFDMA), single-carrier frequency division multiple access (Single-carrier Frequency-Division Multiple Access, SC-FDMA), and other systems. The terms "system" and "network" are often used interchangeably. A CDMA system may implement radio technologies such as CDMA2000, universal terrestrial radio access (Universal Terrestrial Radio Access, UTRA), and the like. UTRA includes wideband CDMA (Wideband Code Division Multiple Access, WCDMA) and other CDMA variants. TDMA systems may implement radio technologies such as the global system for mobile communications (Global System for Mobile Communication, GSM). OFDMA systems may implement radio technologies such as ultra mobile broadband (UltraMobile Broadband, UMB), evolved UTRA (E-UTRA), IEEE 802.21 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, flash-OFDM, and the like. UTRA and E-UTRA are parts of the universal mobile telecommunications system (Universal Mobile Telecommunications System, UMTS). LTE and higher LTE (e.g., LTE-a) are new UMTS releases that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-a and GSM are described in the literature from an organization named "third generation partnership project" (3rd Generation Partnership Project,3GPP). CDMA2000 and UMB are described in the literature from an organization named "third generation partnership project 2" (3 GPP 2). The techniques described herein may be used for the systems and radio technologies mentioned above as well as for other systems and radio technologies. However, the following description describes an NR system for purposes of example, and NR terminology is used in much of the description below, although the techniques may also be applied to applications other than NR system applications.

The following description provides examples and does not limit the scope, applicability, or configuration as set forth in the claims. Changes may be made in the function and arrangement of elements discussed without departing from the spirit and scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For example, the described methods may be performed in an order different than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

Referring to fig. 1, fig. 1 is a block diagram of a wireless communication system to which an embodiment of the present invention is applicable. The wireless communication system includes a terminal 11 and a network device 12. The terminal 11 may also be referred to as a User terminal or a User Equipment (UE), and the terminal 11 may be a terminal-side Device such as a mobile phone, a tablet Computer (Tablet Personal Computer), a Laptop (Laptop Computer), a personal digital assistant (Personal Digital Assistant, PDA), a mobile internet Device (Mobile Internet Device, MID), a Wearable Device (Wearable Device), or a vehicle-mounted Device, which is not limited to a specific type of the terminal 11 in the embodiment of the present invention. The network device 12 may be a base station and/or a core network element, where the base station may be a 5G or later version base station (e.g., a gNB, a 5G NR NB, etc.), or a base station in another communication system (e.g., an eNB, a WLAN access point, or other access points, etc.), where the base station may be referred to as a node B, an evolved node B, an access point, a base transceiver station (Base Transceiver Station, a BTS), a radio base station, a radio transceiver, a basic service set (Basic Service Set, BSS), an extended service set (Extended Service Set, ESS), a node B, an evolved node B (eNB), a home node B, a home evolved node B, a WLAN access point, a WiFi node, or some other suitable terminology in the field, and the base station is not limited to a specific technical vocabulary, and in the embodiment of the present invention, the base station in the NR system is merely an example, but is not limited to a specific type of the base station.

The base stations may communicate with the terminal 11 under the control of a base station controller, which may be part of the core network or some base stations in various examples. Some base stations may communicate control information or user data with the core network over a backhaul. In some examples, some of these base stations may communicate with each other directly or indirectly over a backhaul link, which may be a wired or wireless communication link. A wireless communication system may support operation on multiple carriers (waveform signals of different frequencies). A multicarrier transmitter may transmit modulated signals on the multiple carriers simultaneously. For example, each communication link may be a multicarrier signal modulated according to various radio technologies. Each modulated signal may be transmitted on a different carrier and may carry control information (e.g., reference signals, control channels, etc.), overhead information, data, and so on.

The base station may communicate wirelessly with the terminal 11 via one or more access point antennas. Each base station may provide communication coverage for a respective corresponding coverage area. The coverage area of an access point may be partitioned into sectors that form only a portion of that coverage area. A wireless communication system may include different types of base stations (e.g., macro base stations, micro base stations, or pico base stations). The base station may also utilize different radio technologies, such as cellular or WLAN radio access technologies. The base stations may be associated with the same or different access networks or operator deployments. The coverage areas of different base stations, including coverage areas of the same or different types of base stations, coverage areas utilizing the same or different radio technologies, or coverage areas belonging to the same or different access networks, may overlap.

The communication link in the wireless communication system may include an Uplink for carrying Uplink (UL) transmissions (e.g., from the terminal 11 to the network device 12) or a Downlink for carrying Downlink (DL) transmissions (e.g., from the network device 12 to the terminal 11). UL transmissions may also be referred to as reverse link transmissions, while DL transmissions may also be referred to as forward link transmissions. Downlink transmissions may be made using licensed bands, unlicensed bands, or both. Similarly, uplink transmissions may be made using licensed bands, unlicensed bands, or both.

As described in the background art, the accuracy of the TAL construction method with the UE as the center in the prior art is greatly affected by the time-varying characteristics of the mobility behavior of the UE based on the long-term UE movement data history. For example, moysen in "Learning-based Tracking Area List Management in 4G and 5G Networks" proposes a user (i.e., UE) -centric TAL construction method. The method analyzes and learns the average mobility behavior of the UE in a specific period, and classifies the UE based on whether the position sequence of the UE is fixed or predictable; and generating an optimized tracking area list for each UE by adopting a corresponding strategy (such as single-target or multi-target optimization) according to the UE type and the predicted UE route. The method has good accuracy for the UE with high periodic movement, but for the UE with non-periodic movement, the accuracy of TAL construction is difficult to ensure. For example, if the UE enters a new location where there is no available movement history, it may not be possible to estimate the UE's location to dynamically build TAL, which would affect KPIs associated with the mobile communication system, such as paging success rate.

In order to solve at least one of the above problems, the embodiment of the present invention provides a method for constructing a tracking area list, which can reduce signaling cost and alleviate network congestion. The method for constructing the tracking area list is applied to network function entities, wherein the network function entities can be entities such as a network data analysis function (Network Data Analytics Function, NWDAF) and/or a management data analysis function (Management Data Analytic Function, MDAF). Referring to fig. 2, the method includes:

and step 21, constructing a candidate cell set according to the current position of the first user equipment and the service information.

Here, according to the current position and service information of the first user equipment, a candidate cell capable of providing service for the first user equipment is selected to form the candidate cell set. The service information may specifically include information such as resources, capabilities, etc. required by the service being executed by the first user equipment and/or the service to be executed. And forming the candidate cell set by selecting cells which cover the current position of the first user equipment and meet the service information of the first user equipment. That is, the candidate cell needs to cover the current location of the first ue, for example, the signal strength or signal quality of the candidate cell received by the first ue meets a preset threshold. In addition, the candidate cell also has resources and/or capabilities required by the service information of the first user equipment.

And step 22, selecting an optimal service cell based on the candidate cell set.

Here, in the embodiment of the present invention, there are various ways to select the optimal serving cell:

for example, a cell with the highest received signal strength or the best signal quality of the first user equipment may be selected from the candidate cell set as the optimal serving cell.

For another example, the scores of the candidate cells may be calculated by combining the received signal strength, the received signal quality, the cell load, and other conditions of the cells, and then the cell with the highest score may be selected as the optimal serving cell.

For another example, the embodiment of the present invention may also consider the moving direction of the first user equipment to select an optimal serving cell. Specifically, the position sequence of the movement of the first user equipment can be predicted through a prediction algorithm of the movement track of various terminals, so that the next position of the first user equipment is obtained. Here "next location" means a new location where the first user equipment is located at a certain moment in the future. And then, determining the moving direction of the first user equipment according to the current position of the first user equipment and the next position. And selecting a candidate cell with the smallest included angle with the moving direction from the candidate cell set as an optimal service cell according to the moving direction of the first user equipment. The selection mode considers the moving direction of the terminal, so that the selected optimal service cell is matched with the moving track of the user equipment, thereby being capable of serving the user equipment for a long time and reducing the updating times of the optimal service cell.

Step 23, determining the service TAL of the first ue according to the TAL to which the optimal serving cell belongs.

Here, the TAL to which the optimal serving cell belongs is used as a serving TAL of the first user equipment, and the network function entity may further send configuration information to the first user equipment, so as to configure the serving TAL for the first user equipment. Specifically, the network function entity may send the information of the service TAL to a mobility management function entity, and send the information of the service TAL to the first user equipment through the mobility management function entity.

Through the steps, the embodiment of the invention constructs the candidate cell set according to the current position and the service information of the first user equipment, so that the optimal service cell and the service TAL are determined for the first user equipment, the mobile and service characteristics of the user equipment can be met, and the updating of the service TAL is reduced.

As an implementation manner, in the step 23, an embodiment of the present invention may construct an initial TAL set of the first user equipment, where the initial TAL set includes at least one TAL. And then, determining the service TAL of the first user equipment according to the TAL of the optimal service cell in the initial TAL set.

Specifically, constructing the initial TAL set of the first user equipment may further include the following steps:

a) And collecting the position information and service information of the first user equipment.

Here, current position information and historical position information in a preset latest period of time of the first user equipment are collected, and service information of the first user equipment at each position is collected.

b) And determining an initial TAL set of the first user equipment meeting a first target according to the collected position information and service information of the first user equipment, wherein the first target is to minimize the number of signaling used for updating and/or paging of a tracking area.

Here, the active area of the first user equipment may be determined based on the current location of the first user equipment and the historical location in the last period of time, and for all cells in the active area, an existing machine learning algorithm is used to construct an initial TAL set that takes into account both the tracking area update cost and the user paging signaling cost. For example, reference is made to the relevant literature Learning-based Tracking Area List Management in 4G and 5G Networks,J.Moysen; and (3) a TAL construction method centered on a user (namely User Equipment (UE), a terminal) in M.GarcI a-Lozano, wireless Communications and Technologies Research Group, signal Theory and Communications Department, UPC, IEEE Transactions on Mobile Computing, 2020.

In a specific implementation, the number of the optimal serving cells may be greater than or equal to 1. For example, if there are two candidate cells in the set of candidate cells, the angle between the candidate cells and the moving direction is the smallest, there are 2 best serving cells.

And if the number of the optimal service cells is greater than one, determining the TAL to which the optimal service cell belongs as the service TAL of the first user equipment if all the optimal service cells belong to the same TAL. If all the optimal service cells do not belong to the same TAL, the TAL to which the optimal service cell whose coverage area satisfies the first condition belongs may be determined as the service TAL of the first user equipment. Here, the first condition includes any one of: the coverage is maximum; the coverage area is minimum; the coverage is in a first interval.

When determining the service TAL of the first ue according to the TAL to which the optimal serving cell belongs in the initial TAL set, the TAL to which the optimal serving cell belongs refers to the TAL to which the optimal serving cell belongs in the initial TAL set.

In the embodiment of the present invention, the TAL update of the first user equipment may include an update of a service TAL and/or an update of an optimal serving cell. The embodiment of the invention can further realize the rapid updating of the service TAL by constructing the candidate service TAL of the first user equipment. In this way, when the first user equipment moves out of the service TAL, the candidate service TAL may be used as a new service TAL for the first user equipment.

Specifically, a candidate service TAL of the first user equipment may be determined according to a TAL to which at least one cell in the candidate cell set belongs, where the candidate service TAL is different from the service TAL.

Here, the candidate service TAL is a TAL satisfying a second condition, which may include any one of: the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is greater than a first threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is less than a second threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is in a second interval.

Similarly, in embodiments where the service TAL is a TAL of the initial TAL set, the candidate service TAL is also in the initial TAL set.

In the embodiment of the present invention, the optimal serving cell and/or the updated serving TAL may also be updated when the first ue moves out of the optimal serving cell. For example, a candidate cell other than the optimal serving cell may be selected in the serving TAL of the first user equipment as a new optimal serving cell. At this time, the new best serving cell should cover the current location of the first ue. For another example, the embodiment of the present invention may also re-execute the above steps 21 to 23 to re-determine the new optimal serving cell and the service TAL, that is: constructing a new candidate cell set according to the current position and service information of the first user equipment; then, selecting a new optimal serving cell based on the new candidate cell set; and then, determining a new service TAL of the first user equipment according to the TAL of the new optimal service cell.

From the above, it can be seen that the above method of the embodiment of the present invention uses the idea of centering on the ue, dynamically constructs the tracking area list along with the ue movement, and simultaneously considers the update of the registration area RA (i.e., the tracking area list TAL) and the paging signaling cost of the ue, so that the service TAL can provide high-quality and long-time service for the ue.

To facilitate a better understanding of the above method, several examples of methods of constructing the tracking area list are provided below, one of which includes:

in step 31, when the user equipment initially accesses the core network, user equipment information such as location information, service information, etc. is collected.

In step 32, after a certain amount of information of the ue is collected, such as current location information, historical location information, current service requirement, and historical traffic, an initial TAL set that takes into account the tracking area update cost and the user paging signaling cost can be constructed by using an existing machine learning algorithm according to the historical path rule and the service paging rule of the ue. For example, based on the current location of the user equipment and the historical location within a certain period of time, the user activity area is determined, and for all cells in the user equipment activity area, an initial TAL set is constructed by using an existing machine learning algorithm, which takes into account both the tracking area update cost and the user paging signaling cost.

In step 33, after the ue accesses the core network, a candidate cell set is constructed with the ue as a center, which may specifically include three subfunctions of predicting the ue direction, screening the initial candidate set, and determining the candidate cell set.

a) User equipment direction prediction: the existing location prediction algorithm is used to predict the next location of the user equipment. And connecting the longitude and latitude coordinates of the current position of the user with the longitude and latitude coordinates of the predicted position to obtain the moving direction of the user equipment.

b) Screening an initial candidate set: and screening the cells which can meet the conditions of the received signal strength and the service requirement of the user equipment. Based on the user equipment information collected in step 31, such as location information and service information, selecting cells around the user equipment that meet the received signal strength and service requirement conditions (e.g. cell capability to support a specific service or characteristic, cell load conditions, service QoS requirements, service duration, i.e. service time requirements, etc.), and constructing an initial candidate cell set.

c) Determining a candidate cell set: connecting the current position of the user with each cell in the initial candidate cell set, generating an included angle with the moving direction of the user equipment, forming an included angle set, arranging the set in an ascending order, selecting the cell with the smallest included angle as the optimal service cell (possibly 1 or more than 1 cell with the smallest included angle) of the candidate cell set, and selecting the cell with the angle in the included angle set within a preset angle range (such as an acute angle or a right angle or less than 60 degrees) as the candidate cell set of the current position of the user equipment.

In step 34, the TAL construction module centered on the user equipment: based on the initial TAL set and the candidate cell set, TAL which takes signaling cost into consideration and takes user equipment as a center is constructed, and the TAL comprises three subfunctions of candidate cell set classification, service TAL selection and candidate service TAL recommendation.

a) Candidate cell set classification (i.e.: mapping cells in the candidate set of cells to TAL in the initial TAL set): and determining the TA of each candidate cell in the candidate cell set based on the candidate cell set, and further determining the TAL set containing the candidate cells in the initial TAL set. For example, the initial TAL set is { TAL1, TAL2, TAL3}, and the candidate cells in the candidate cell set belong to TAs in TAL1 and TAL2, the TAL set including the candidate cells in the initial TAL set is { TAL1, TAL2}, and different candidate cells are classified (/ homed) to TAL1 and TAL2, respectively, according to the TA to which they belong.

b) Service TAL selection: and taking the TAL where the optimal serving cell is as a serving TAL. For example: the optimal serving cell is in TAL1, TAL1 is the serving TAL. When a plurality of optimal serving cells exist, if the optimal serving cells belong to the same TAL (may belong to the same TA or different TAs in the TAL), the TAL is taken as a serving TAL; if the optimal serving cells belong to different TAL, the TAL with the largest coverage area may be selected as the serving TAL, i.e. the serving TAL is determined as the current registration area of the user equipment.

c) Candidate service TAL recommendation: the ratio of the coverage of each TAL (e.g., TAL 2) other than the serving TAL obtained in the candidate cell set classification to the coverage of the calculated serving TAL (e.g., TAL 1) is calculated, and when the ratio is within a threshold range, the other TAL is added to the candidate serving TAL set. One or more candidate service TAL may be contained within the candidate service TAL set. The purpose of this step is to determine if a candidate service TAL currently exists. When the user equipment triggers a service TAL update in an abnormal situation (e.g. in a short time), it may be considered to use a candidate service TAL of the candidate service TAL set as a new service TAL, see step 35.

In step 35, the ue may have moved out of the best serving cell, or even out of the serving TAL, due to movement or the like. When the ue moves out of the optimal serving cell and is still within the current range of the TAL, step 36 is entered; when the user equipment moves out of the current service TAL, step 37 is entered.

In step 36, the ue moves out of the optimal serving cell, when the ue is still in the current serving TAL range, for example, when the ue is still in the current serving TAL range, but the received signal strength between the optimal serving cell and the ue is always lower than the threshold value in the time of the timer T, at this time, the ue triggers the serving cell update in the TAL, and may select, as a new optimal serving cell, a candidate cell other than the optimal serving cell in the serving TAL of the first ue, thereby completing the intra-TAL serving cell update. A specific selection manner may be selected with reference to the manner of sorting based on the angle size above, for example, predicting the next position of the user equipment; determining the moving direction of the user equipment according to the current position and the next position of the user equipment; and further selecting a candidate cell with the smallest included angle with the moving direction from the candidate cell set as an optimal serving cell according to the moving direction of the user equipment.

Of course, in step 36, the candidate cell set construction and TAL construction may also be re-performed, i.e. a new candidate cell set is re-constructed according to the current location and service information of the user equipment; selecting a new optimal serving cell based on the new candidate cell set; and determining a new service TAL of the user equipment according to the TAL of the new optimal service cell.

In step 37, the ue moves out of the current service TAL, and one processing manner is to take a certain candidate service TAL (a certain candidate service TAL may be arbitrarily selected) in the candidate service TAL set as a new service TAL of the ue, and select an optimal serving cell from the new service TAL, where a specific selection manner may refer to the manner based on the angle ranking above. For example, when the ue is within the candidate service TAL, or when the ue triggers a service TAL update under abnormal conditions (e.g., the ue leaves the service TAL for a short time), the candidate service TAL may be directly used as a new service TAL. Another processing way is to re-execute the candidate cell set construction and TAL construction, i.e. reconstruct a new candidate cell set according to the current location and service information of the user equipment; selecting a new optimal serving cell based on the new candidate cell set; and determining a new service TAL of the user equipment according to the TAL of the new optimal service cell.

Referring to fig. 4, an example of an interaction flow between devices in a method for constructing a tracking area list according to an embodiment of the present invention is provided, where the method includes:

400. the user equipment UE initiates a registration request to the network. Specifically, the UE sends a registration request to an access and mobility management function entity (Access and Mobility Management Function, AMF) through an access network, where the registration request carries parameters such as a UE identifier and a UE location.

401. Network function entities, such as a network data analysis function entity (NWDAF) or a Management Data Analysis Function (MDAF), collect information of the user equipment, such as location information, service information. Specifically, the network function entity sends a user location information collection request to the AMF and sends a user equipment service information collection request to an application function entity (AF). AMF and AF report user equipment location information and user service information to the network function entity.

402. Initial TAL set construction: based on the current location of the user equipment and the historical location (within a certain time), determining a user active area, according to the historical path law and the service paging law of the user equipment, the network function entity selects a registration area, namely a Tracking Area List (TAL), for all cells in the user equipment active area by using the existing machine learning algorithm, and considers the updating of a registration area RA (namely the tracking area list TAL) and the cost of user paging signaling, as shown in fig. 5, the initial tracking area list of the user equipment is TAL1, TAL2 and TAL3, wherein for simplicity of presentation, it is assumed that a certain number of cells exist in the user equipment active area, and the shapes of TA and TAL can be irregular patterns.

403. Candidate cell set construction: when the user equipment is accessed to the network, the network functional entity builds a candidate cell set by taking the user equipment as the center.

1) User equipment direction prediction: and predicting the next position of the user equipment by using the existing position prediction algorithm, and connecting the current point coordinate and the predicted point coordinate of the user equipment to obtain the moving direction of the user equipment.

2) Screening an initial candidate cell set: and screening the cells which can meet the conditions of the received signal strength and the service requirement of the user equipment. And selecting cells around the user, which meet the conditions of the received signal strength and the service requirement (such as the capability of the cell to support a specific service or characteristic, the cell load condition, the service QoS requirement, the service persistence, i.e. the service time requirement, etc.), according to the current information of the user collected in step 401, such as the location information and the service information, and constructing an initial candidate cell set. The initial set of candidate cells includes a plurality of candidate cells, such as the cells within the circle in fig. 6.

3) Determining a candidate cell set: connecting the current position of the user equipment with each candidate cell in the initial candidate cell set to obtain an edge, forming an included angle with the moving direction of the user equipment, thereby obtaining an included angle set, arranging included angles in the set according to the ascending order of the included angle, selecting a cell with the smallest included angle as an optimal serving cell of the candidate cell set, such as a cell to which a base station 61 belongs in fig. 6, and selecting a cell with an acute angle or a right angle in the included angle set, such as a cell in a broken line box in fig. 6, as a candidate cell set of the current position of the user equipment.

404. Constructing a user-centric TAL: based on the initial TAL set and the candidate cell set, the network function entity constructs a TAL that takes into account signaling cost and is centered on the user.

1) Candidate cell set classification (i.e.: mapping cells in the candidate set of cells to TAL in the initial TAL set): based on the candidate cell set obtained in step 403, determining the TA where each candidate cell in the candidate cell set is located, and further determining the TAL set including the candidate cell in the initial TAL set. For example: candidate cells in the candidate cell set belong to TA2, TA4, TA1 'and TA2', while TA2 and TA4 belong to TAL1, TA1 'and TA2' belong to TAL2, and the TAL set including the candidate cells in the initial TAL set is { TAL1|ta2, TA4} and { TAL2|ta1', TA2' }, and different candidate cells are classified (/ assigned) to TAL1 and TAL2, respectively, according to the TA to which they belong. As shown in fig. 6.

2) Service TAL selection: and taking the TAL where the optimal service cell is as a service TAL based on the optimal service cell in the 'candidate cell set construction'. For example: the optimal serving cell is in TAL1, TAL1 is the serving TAL. When a plurality of optimal serving cells exist, if the optimal serving cells belong to the same TAL (may belong to the same TA or different TAs in the TAL), the TAL is taken as a serving TAL; if the optimal serving cells belong to different TAL, the TAL with the largest coverage area may be selected as the serving TAL. As shown in fig. 6, the optimal serving cell is located at TA4 in TAL1, and thus { TAL1|ta2, TA4} is taken as a serving TAL, which is determined as the current registration area of the user equipment.

3) Candidate service TAL recommendation: the ratio of the coverage of each other TAL (e.g., TAL 2) except the serving TAL obtained in the candidate cell set classification to the coverage of the serving TAL (e.g., TAL 1) is calculated, and when the ratio is within the threshold range, the other TAL is added to the candidate serving TAL set. One or more candidate service TAL may be contained within the candidate service TAL set. In this example, the threshold range is set to [0.5,1.5], that is, between 0.5 and 1.5, { TAL2|ta1', TA2' } is taken as a candidate service TAL for the user because the ratio of the coverage of TAL2 to the coverage of TAL1 is 0.6, as shown in fig. 6. Finally, the network function outputs a candidate service TAL set { TAL2|ta1', TA2' } and a service TAL { TAL1|ta2, TA4}. When the user equipment triggers a service TAL update in an abnormal situation (e.g. in a short time less than a certain preset duration), it may be considered to use a candidate service TAL of the candidate service TAL set as a new service TAL, see step 405.

405-406, if the network function entity is not an access and mobility management function entity AMF, the network function entity sends a service TAL to the AMF. The AMF sends a registration accept message to the user equipment, carrying the registration area (i.e. the service TAL). Optionally, the network function entity also sends the candidate service TAL set to the AMF; when a user triggers a service TAL update under abnormal conditions (e.g., in a short time less than a certain preset duration), the AMF may directly consider using the TAL in the candidate set of service TAL as a new service TAL (i.e., a new registration area).

407. When the user equipment leaves the current service cell or service TAL, the AMF reports the latest position of the user equipment to the network function entity. Optionally, the AF also reports the latest service information of the user equipment to the network functional entity.

408. If the ue leaves the current serving cell but is still within the current serving TAL, the network function entity performs candidate cell set construction in step 403, outputs the target serving cell, and completes the intra-TAL serving cell update. If the user leaves the current service TAL but the user equipment triggers the service TAL update under abnormal conditions (for example, in a short time less than a certain preset duration), and the current location of the user equipment is in a certain candidate service TAL in the candidate service TAL set obtained in step 404, the network function entity adopts the candidate service TAL as a new service TAL. Otherwise, the network function entity performs the candidate cell set construction of step 403 and the construction of step 404 with the TAL centered on the user based on the latest location of the user, to obtain a new service TAL and a new candidate service TAL set.

409-410. If the network function is not an access and mobility management function AMF, the network function sends a new service TAL (and optionally also a set of candidate services TAL) to the AMF. The AMF updates the registration area (i.e., the new service TAL) to the user equipment; specifically, the AMF may send a configuration update message to the user equipment, wherein the updated registration area (i.e. new service TAL) is carried.

The foregoing describes various methods of embodiments of the present invention. An apparatus for carrying out the above method is further provided below.

Referring to fig. 7, an embodiment of the present invention provides a network functional entity, including:

a construction unit 71, configured to construct a candidate cell set according to the current location and service information of the first user equipment;

a selection unit 72 for selecting an optimal serving cell based on the candidate cell set;

a determining unit 73, configured to determine a service TAL of the first user equipment according to the TAL to which the optimal serving cell belongs.

Optionally, the construction unit is further configured to select a cell that covers the current location of the first user equipment and satisfies service information of the first user equipment, to form the candidate cell set.

Optionally, the selecting unit is further configured to predict a next position of the first user equipment; determining the moving direction of the first user equipment according to the current position and the next position of the first user equipment; and selecting a candidate cell with the smallest included angle with the moving direction from the candidate cell set as an optimal service cell according to the moving direction of the first user equipment.

Optionally, the determining unit includes:

an initial set building unit, configured to build an initial TAL set of the first user equipment, where the initial TAL set includes at least one TAL;

and the service TAL determining unit is used for determining the service TAL of the first user equipment according to the TAL of the optimal service cell in the initial TAL set.

Optionally, the initial set building unit is further configured to:

Optionally, the determining unit is further configured to:

in case the number of the optimal serving cells is greater than one:

Optionally, the network function entity further includes:

a candidate service TAL determining unit, configured to determine a candidate service TAL of the first user equipment according to a TAL to which at least one cell in the candidate cell set belongs, where the candidate service TAL is different from the service TAL;

and the first updating unit is used for taking the candidate service TAL as a new service TAL of the first user equipment when the first user equipment moves out of the service TAL.

Optionally, the candidate service TAL is in the initial TAL set.

Optionally, the candidate service TAL satisfies a second condition, where the second condition includes any one of the following: the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is greater than a first threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is less than a second threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is in a second interval.

Optionally, the network function entity further includes:

A second updating unit, configured to, in case the first user equipment moves out of the optimal serving cell:

Optionally, the network function entity is a network data analysis function NWDAF entity and/or a management data analysis function MDAF entity; the network function entity further comprises:

and the sending unit is used for sending the information of the service TAL to a mobility management functional entity, and sending the information of the service TAL to the first user equipment through the mobility management functional entity.

The device in this embodiment is a device corresponding to the method for constructing the tracking area list, and the implementation manners in the foregoing embodiments are all applicable to the embodiment of the device, so that the same technical effects can be achieved. The device provided by the embodiment of the invention can realize all the method steps realized by the embodiment of the method and can achieve the same technical effects, and the parts and the beneficial effects which are the same as those of the embodiment of the method in the embodiment are not described in detail.

Referring to fig. 8, an embodiment of the present invention provides a schematic structural diagram of an apparatus for constructing a tracking area list, where the apparatus is applied to a base station, and specifically includes: a processor 801, a transceiver 802, a memory 803, and a bus interface, wherein:

in an embodiment of the present invention, the apparatus further includes: a program stored on the memory 803 and executable on the processor 801,

the transceiver 802 is configured to receive and transmit data under the control of the processor;

the processor 801 is configured to read the computer program in the memory and perform the following operations:

selecting an optimal serving cell based on the candidate cell set;

Optionally, the processor is further configured to read the computer program in the memory and perform the following operations:

Predicting a next location of the first user device;

in case the number of the optimal serving cells is greater than one:

Optionally, the candidate service TAL is in the initial TAL set.

Optionally, the network function entity is a network data analysis function NWDAF entity and/or a management data analysis function MDAF entity;

It can be appreciated that in the embodiment of the present invention, the computer program, when executed by the processor 801, may implement the respective processes of the embodiment of the method for constructing a tracking area list, and achieve the same technical effects, so that repetition is avoided and no further description is given here.

In fig. 8, a bus architecture may be comprised of any number of interconnected buses and bridges, and in particular, one or more processors represented by the processor 801 and various circuits of the memory represented by the memory 803. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, power management circuits, etc., which are well known in the art and, therefore, will not be described further herein. The bus interface provides an interface. The transceiver 802 may be a number of elements, i.e., including a transmitter and a receiver, providing a means for communicating with various other apparatus over a transmission medium.

The processor 801 is responsible for managing the bus architecture and general processing, and the memory 803 may store data used by the processor 801 in performing operations.

The terminal in this embodiment is a device corresponding to the method shown in fig. 5, and the implementation manners in the foregoing embodiments are all applicable to the embodiment of the terminal, so that the same technical effects can be achieved. In the device, the transceiver 802 and the memory 803, and the transceiver 802 and the processor 801 may be communicatively connected through a bus interface, where the functions of the processor 801 may be implemented by the transceiver 802, and the functions of the transceiver 802 may be implemented by the processor 801. It should be noted that, the above device provided in the embodiment of the present invention can implement all the method steps implemented in the method embodiment and achieve the same technical effects, and detailed descriptions of the same parts and beneficial effects as those of the method embodiment in the embodiment are omitted herein.

In some embodiments of the present invention, there is also provided a computer-readable storage medium having stored thereon a program which, when executed by a processor, performs the steps of:

when the program is executed by the processor, all the implementation modes in the method for constructing the tracking area list can be realized, and the same technical effects can be achieved, so that repetition is avoided, and the description is omitted here.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, and are not repeated herein.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown 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 units may be selected according to actual needs to achieve the purpose of the embodiment of the present invention.

In addition, each functional unit in the embodiments of the present invention may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method described in the embodiments of the present invention. And the aforementioned storage medium includes: a usb disk, a removable hard disk, a ROM, a RAM, a magnetic disk, or an optical disk, etc.

The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present invention. Therefore, the protection scope of the invention is subject to the protection scope of the claims.

Claims

1. The construction method of tracking area list TAL is applied to network function entity and is characterized by comprising the following steps:

selecting an optimal serving cell based on the candidate cell set;

2. The method of claim 1, wherein constructing the candidate set of cells based on the current location of the first user device and the traffic information comprises:

3. The method of claim 1, wherein the selecting an optimal serving cell based on the set of candidate cells comprises:

Predicting a next location of the first user device;

4. The method of claim 1, wherein the determining the serving TAL for the first user equipment based on the TAL to which the optimal serving cell belongs comprises:

5. The method of claim 4, wherein the constructing the initial TAL set for the first user device comprises:

6. The method of claim 1, wherein the determining the serving TAL for the first user equipment based on the TAL to which the optimal serving cell belongs comprises:

in case the number of the optimal serving cells is greater than one:

7. The method of claim 1 or 4, further comprising:

when the first user device moves out of the service TAL,

and taking the candidate service TAL as a new service TAL of the first user equipment.

8. The method of claim 7, wherein the candidate service TAL is in the initial TAL set.

9. The method of claim 7, wherein the candidate service TAL satisfies a second condition, the second condition comprising any of: the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is greater than a first threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is less than a second threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is in a second interval.

10. The method of claim 1, wherein in the event that the first user device moves out of the optimal serving cell, the method further comprises:

11. The method of claim 1, wherein,

the network function entity is a network data analysis function NWDAF entity and/or a management data analysis function MDAF entity; the method further comprises the steps of:

12. The device for constructing the tracking area list is characterized by being applied to network functional entities and comprising a memory, a transceiver and a processor, wherein,

the memory is used for storing a computer program;

selecting an optimal serving cell based on the candidate cell set;

13. The apparatus of claim 12, wherein the processor is further configured to read a computer program in the memory and perform the following:

14. The apparatus of claim 12, wherein the processor is further configured to read a computer program in the memory and perform operations comprising:

predicting a next location of the first user device;

15. The apparatus of claim 12, wherein the processor is further configured to read a computer program in the memory and perform operations comprising:

16. The apparatus of claim 15, wherein the processor is further configured to read a computer program in the memory and perform operations comprising:

17. The apparatus of claim 12, wherein the processor is further configured to read a computer program in the memory and perform operations comprising:

in case the number of the optimal serving cells is greater than one:

18. The apparatus of claim 15 or 17, wherein the processor is further configured to read a computer program in the memory and perform the following:

19. The apparatus of claim 18, wherein the candidate service TAL is in the initial TAL set.

20. The apparatus of claim 18, wherein the candidate service TAL satisfies a second condition, the second condition comprising any of: the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is greater than a first threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is less than a second threshold; the ratio of the coverage of the candidate service TAL to the coverage of the service TAL is in a second interval.

21. The apparatus of claim 12, wherein the processor is further configured to read a computer program in the memory and perform operations comprising:

22. The apparatus of claim 12, wherein the network function entity is a network data analysis function, NWDAF, entity and/or a management data analysis function, MDAF, entity;

23. A network function entity, comprising:

24. A processor-readable storage medium, characterized in that the processor-readable storage medium stores a computer program for causing the processor to perform the method of any one of claims 1 to 11.