WO2014098338A1

WO2014098338A1 - Method and device for managing tracking area

Info

Publication number: WO2014098338A1
Application number: PCT/KR2013/006717
Authority: WO
Inventors: 서성훈; 현재섭; 김현표; 정진수
Original assignee: 주식회사 케이티
Priority date: 2012-12-21
Filing date: 2013-07-26
Publication date: 2014-06-26
Also published as: KR20140083082A; KR101487488B1

Abstract

The present invention relates to a method of managing a tracking area using a tracking area managing device in a network that includes at least one digital signal processing device and a plurality of wireless signal processing devices connected to the digital signal processing devices, respectively. The method includes: receiving information on a first tracking area related to a terminal from a mobility management entity; changing the information on the first tracking area to information on a second tracking area based on at least one item of information regarding where the terminal moves and configuration information on the network; and transmitting a tracking area update accept message including the information on the second tracking area to a wireless signal processing device to which the terminal is connected.

Description

Tracking area management method and device

The present invention relates to a tracking area management method and apparatus.

The tracking area (TA) is a minimum unit criterion for determining the final position of the terminal and is composed of a cell unit or a set of cells. A mobility management entity (MME) manages a tracking area.

When the terminal leaves the tracking area, the terminal transmits a tracking area update (TAU) request message to the base station. The base station delivers a tracking area update request message to the MME. The MME updates the tracking area of the terminal. The tracking area information updated by the request of the terminal is transmitted to the terminal by the tracking area update permission message, and the terminal determines whether to request the next tracking area update based on the tracking area identifier list included in the received tracking area update permission message. To judge.

When a data packet arrives from the Internet through a packet gateway (Packet Gateway or PDN (Packet Data Network) Gateway (P-GW)) to a serving gateway (S-GW), the serving gateway sends a paging message to the MME. Request the transfer. The MME requests all base stations in the tracking area of the terminal to transmit a paging message. The base stations that are requested to transmit the paging message transmit the paging message to find the corresponding terminal.

Meanwhile, a network environment in which a base station is physically separated into a radio signal processing unit (RU) and a digital signal processing unit (Digital Unit, DU) has been proposed. A wireless signal processing device installed in a service target area performs wireless signal processing, and a digital signal processing device installed intensively in a national company performs digital signal processing. However, in a distributed communication system in which the wireless signal processing device and the digital signal processing device are dynamically installed by location addition / change or relocation, the mobility management object is difficult to manage the tracking area.

The present invention has been made in an effort to provide a tracking area management method and apparatus for dynamically changing a tracking area identifier list generated by a mobility management object.

A tracking area management device manages a tracking area in a network composed of at least one digital signal processing device and a plurality of wireless signal processing devices connected to each digital signal processing device. Receiving first tracking area information related to a terminal from a mobility management entity, and converting the first tracking area information to second tracking area information based on at least one of movement information of the terminal and configuration information of the network. And changing a tracking area update accept message including the second tracking area information to a wireless signal processing device to which the terminal is connected.

The tracking area information may include a tracking area identifier (TAI) list.

The setting information of the network may include at least one of connection information of the digital signal processing apparatus and the wireless signal processing apparatus, resource information of the digital signal processing apparatus and the wireless signal processing apparatus, and geographic information of the wireless signal processing apparatus. have.

The second tracking area information may include a tracking area narrower than the first tracking area information.

The changing to the second tracking area information may include searching for a wireless signal processing device related to a moving path of the terminal based on the movement information of the terminal, and including the identification information of the found wireless signal processing device. Tracking area information can be generated.

The changing to the second tracking area information may include extracting a tracking area code (TAC) related to the terminal based on at least one of movement information of the terminal and setting information of the network, and extracting the tracking area code. The second tracking area information including may be generated.

In the changing of the second tracking area information, the second tracking area information may be generated by grouping wireless signal processing devices connected to a plurality of digital signal processing devices.

A tracking area management apparatus manages a tracking area in a network including at least one digital signal processing device and a plurality of wireless signal processing devices connected to each digital signal processing device, according to another embodiment of the present invention. Changing first tracking area information related to the terminal received from a mobility management entity to second tracking area information based on at least one of movement information and configuration information of the network, from the mobility management object Receiving a request to transmit a paging message of a terminal to a tracking area included in the first tracking area information, finding the second tracking area information corresponding to the first tracking area information, and a cell included in the second tracking area. Searching for and processing digital signals related to the found cells Sending a paging message to the device and the wireless signal processing device.

In a network consisting of at least one digital signal processing device and a plurality of wireless signal processing devices connected to each digital signal processing device, a tracking area management device is provided. A first tracking area information related to a terminal from a decision management unit and a mobility management entity that manages the setting information of the terminal, and the second tracking area information is based on the second tracking area information. And a tracking area reconstruction unit configured to reconstruct the tracking area information and to transmit a tracking area update permission message including the second tracking area information to a wireless signal processing device to which the terminal is connected.

The tracking area management apparatus may further include a tracking area mapping storage unit which maps and manages the first tracking area information and the second tracking area information.

When the tracking area management device is requested to transmit a paging message of the terminal to the tracking area included in the first tracking area information from the mobility management object, the tracking area management device receives the second tracking area information corresponding to the first tracking area information. The apparatus may further include a paging unit for searching and transmitting a paging message to the digital signal processing apparatus and the wireless signal processing apparatus included in the second tracking area information.

The tracking area reconstruction unit may search for a wireless signal processing device related to a moving path of the terminal based on the movement information of the terminal, and generate the second tracking area information including information of the found wireless signal processing device. have.

The tracking area reconstruction unit may generate the second tracking area information by tying wireless signal processing devices connected to a plurality of digital signal processing devices, respectively.

According to an exemplary embodiment of the present invention, a tracking area can be managed efficiently in a communication system in which a wireless signal processing device and a digital signal processing device of a base station are separated and operated. According to an exemplary embodiment of the present invention, an unnecessary paging procedure performed by a base station can be reduced by managing a tracking area based on terminal location information.

1 is a diagram illustrating a network structure.

2 is a flowchart of a tracking area update method.

3 is a network environment according to an embodiment of the present invention.

4 is a view for explaining a dynamic tracking area management method according to an embodiment of the present invention.

5 is a diagram illustrating a method of dynamically managing a tracking area based on terminal movement information according to an embodiment of the present invention.

6 is a block diagram of a tracking area management apparatus according to an embodiment of the present invention.

7 is a flowchart of a tracking area management method according to an embodiment of the present invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, except to exclude other components unless specifically stated otherwise.

In addition, the term "... unit" described in the specification means a unit for processing at least one function or operation, which may be implemented in hardware or software or a combination of hardware and software.

In the present specification, a terminal is a mobile station (MS), a mobile terminal (MT), a subscriber station (SS), a portable subscriber station (PSS), a user equipment (User Equipment). It may also refer to a user equipment (UE), an access terminal (AT), and the like, and may include all or some functions of a terminal, a mobile station, a mobile terminal, a subscriber station, a portable subscriber station, a user device, an access terminal, and the like. .

In the present specification, a base station (BS) is an access node (AP), a radio access station (RAS), a radio access station (RAS), a node B (Node B), an advanced node B (evolved NodeB, eNodeB), a base transceiver station (Base Transceiver Station, BTS), MMR (Mobile Multihop Relay) -BS, etc. may be referred to, and all or part of the functions of the access node, base station, radio access station, Node B, eNodeB, transmit and receive base station, MMR-BS, etc. It may also include.

The base station is divided into an apparatus for processing radio signal, a remote radio head (RRH), or a radio unit (RU), and an apparatus for processing digital signal, or a digital unit (DU). Can be implemented.

1 is a diagram illustrating a network structure, and FIG. 2 is a flowchart of a tracking area update method.

Referring to FIG. 1, the base station 100/110 is wirelessly connected to the terminal 10. The base station 100/110 assigns a frequency to the terminal 10 and is in charge of all radio related functions including radio bearer control, admission control, mobility control, scheduling, and security.

The base station 100/110 may include a mobility management entity (MME) 200, a serving gateway (Serving GateWay, S-GW) 300, and a packet gateway (Packet GateWay, P-GW) 400. It is connected to the containing core network.

The MME 200 is connected to the base station 100/110 by wire for the control signaling of the terminal, manages the terminal in the idle mode, and selects the S-GW 300 and the P-GW 400. In addition, the MME 200 performs roaming and authentication-related functions, and processes a bearer signal necessary for management of bearer generation / release / change, etc. generated in the terminal 10.

The MME 200 manages a tracking area identifier (TAI) list. The MME 200 transmits a tracking area identifier list related to the terminal 10 to the terminal 10 to perform the tracking area update in the tracking area other than the tracking area identifier list. When there is a data packet to be transmitted to the terminal 10, the MME 200 requests transmission of a paging message from base stations in a tracking area where the terminal is located.

The S-GW 300 serves as a mobility anchor when the terminal 10 moves.

The P-GW 400 assigns an IP (Internet Protocol) address to the terminal 10, performs packet data related functions of the core network, and the terminal 10 moves between the 3GPP wireless network and the non-3GPP wireless network. If yes, it serves as a mobility anchor.

If the terminal 10 in the tracking area # 1 500 moves to the tracking area # 2 600, the MME 200 performs the tracking area update (TAU) procedure. Obtain information about the tracking area after the movement of.

Referring to FIG. 2, the terminal 10 transmits a tracking area update request (TAU request) message to the base station 100 (S110). The tracking area update request message includes a tracking area code (TAC) to which the base station 100 belongs, for example, TAC10.

The base station 100 transmits a tracking area update request message to the MME 200 (S120).

The MME 200 transmits a TAU Accept message for allowing the tracking area update to the terminal 10 (S130). The MME generates a tracking area identifier (TAI) list based on TACs including the TAC10 received from the terminal 10, for example, TAC09, TAC10, and TAC11. The MME 200 transmits a TAU permission message including a tracking area identifier list to the terminal 10. The tracking area identifier list is a tracking area related to the terminal 10.

The terminal 10 moves to change the access point to the base station 110 (S140). The terminal 10 does not update the tracking area in an area included in the tracking area identifier list. However, when the base station 110 is a base station to which a tracking area code, for example, TAC20, which is not included in the tracking area identifier list, the terminal 10 performs the tracking area update as follows.

The terminal 10 transmits a tracking area update request message to the base station 110 (S150), and the base station 110 transmits a tracking area update request message to the MME 200 (S160).

The MME 200 transmits a TAU Accept message including the updated tracking area identifier list to the terminal 10 (S170). The updated tracking area identifier list may include, for example, TAC19, TAC20, and TAC21.

3 is a network environment according to an embodiment of the present invention.

Referring to FIG. 3, the base station includes an apparatus for processing radio signal, a remote radio head (RRH), or a radio unit (RU), and an apparatus for processing digital signal, or a digital unit (apparatus for processing radio signal). DU)] may be implemented separately.

The network environment includes a plurality of wireless signal processing units (RU) 1100, a plurality of digital signal processing units (DU # 1-DU # n) 1200, an MME 200, and a tracking area management device 1300. do. The tracking area management apparatus 1300 may be connected to a femto gateway (not shown). The tracking area management apparatus 1300 may be separately implemented as shown in FIG. 3 or may be implemented in the DU 1200.

The RU 1100 processes a radio signal, and converts and amplifies a digital signal received from the DU 1200 into a radio frequency (RF) signal according to a frequency band. The RU 1100 is installed in the service area. The set of RUs forms the tracking areas TA # 1-TA # m.

The DU 1200 encrypts or decrypts a wireless digital signal and is connected to the core network. One DU 1200 may manage the plurality of RUs 1100. The DU 1200 may be connected to at least one tracking area.

The MME 200 manages a tracking area identifier (TAI) list. The MME 200 transmits a tracking area identifier list of the terminal 10 to the terminal 10. The MME 200 requests transmission of a paging message to base stations in the tracking area where the terminal 10 is located.

The tracking area management device 1300 is connected to at least one DU. The tracking area management apparatus 1300 dynamically maps a plurality of RUs connected to the DUs DU # 1 -DU # n to dynamically generate a tracking area.

The tracking area management apparatus 1300 receives a tracking area identifier list of the terminal 10 from the MME 200. The tracking area management apparatus 1300 reconstructs the tracking area identifier list of the terminal 10 based on the terminal movement information and the network setting information. The terminal movement information is information for estimating the terminal movement path and is calculated based on the terminal movement pattern or history. The network configuration information may include resource information of the RU / DU, geographic information of the RU, femtoAP information, and the like. Femto AP information is received from a femto gateway.

In a communication system in which RUs and DUs are dynamically connected based on virtualization technology, the MME 200 constructs a tracking area identifier list based on the RU / DU information set at the time of initial installation. I can not know. However, since the tracking area management apparatus 1300 knows information related to the RU / DU, the tracking area management apparatus 1300 may reconfigure the tracking area identifier list by dynamically mapping the RUs. Through this, the tracking area management apparatus 1300 may reduce the paging message unnecessarily sent by the RU.

Referring to FIG. 4, the tracking area management apparatus 1300 reconfigures the tracking area identifier list of the terminal 10 based on the terminal movement information and the network setting information. The network configuration information may include resource information of the RU / DU, geographic information of the RU, femtoAP information, and the like.

The tracking area management apparatus 1300 reconfigures a tracking area suitable for the terminal 10 using at least one of terminal movement information, resource information of the RU / DU, geographic information of the RU, and femtoAP information. In this case, the tracking area management apparatus 1300 may create a tracking area by not only RUs in the same DU but also RUs connected to other DUs. That is, the tracking area management apparatus 1300 may create a tracking area identifier list of the terminal 10 by combining the RUs of TA # 1, the RUs of TA # 2, and the RUs of TA # 3.

The tracking area management apparatus 1300 transmits a paging message directed to the terminal 10 only to the DU / RU of the reconfigured tracking area identifier list.

The list of tracking area identifiers so far is managed by the MME. The MME includes all tracking area codes of the tracking area where the terminal is located in the tracking area identifier list. Thus, unnecessary paging messages have been transmitted throughout the large tracking area. Also, the MME does not know the network configuration information of the RU / DU. Therefore, the MME only considers the fixed tracking area and does not dynamically change the tracking area by combining some RUs included in the neighboring tracking area.

On the other hand, the tracking area management apparatus 1300 may know both network configuration information of the RU / DU and movement information of the terminal. Accordingly, the tracking area management apparatus 1300 does not rely on the tracking areas TA # 1-TA # m set by the MME, but dynamically binds the tracking areas of the terminal 10 by tying RUs located in different tracking areas. I can make it.

Referring to FIG. 5, the tracking area management apparatus 1300 is connected to the MME 200 and the femto gateway 1400. It is assumed that the tracking area management device 1300 is connected to the DU 1200. The DU 1200 processes digital signals of a plurality of cells provided with a plurality of RUs (RU1, RU2, RU3, RU4, RU5, RU6, and RU7).

For example, when the MME 200 bundles RU1, RU2, and RU3 and manages them as a tracking area, when the terminal 10 moves to RU5, the terminal must perform a tracking area update. However, the tracking area management apparatus 1300 may predict that the terminal 10 in RU1 moves in the RU5 direction based on the movement information of the terminal 10. Then, the tracking area management apparatus 1300 may change the tracking area identifier list to include the RU5. In this case, the tracking area management apparatus 1300 may delete a cell that deviates from the moving path of the terminal from the tracking area identifier list of the MME 200 based on the movement information of the terminal 10.

The tracking area management apparatus 1300 may include a tracking area code related to a femto AP in a tracking area identifier list through interworking with the femto gateway 1400.

Referring to FIG. 6, the tracking area management apparatus 1300 includes a determination information management unit 1310, a tracking area reconstruction unit 1330, a tracking area mapping storage unit 1350, and a paging unit 1370.

The determination information manager 1310 may include a terminal mobility information manager 1311, a resource information manager 1313, a geographic information manager 1315 of the RU, and a femto AP information manager 1317.

The terminal mobility information manager 1311 manages information used to predict the terminal movement path. The terminal mobility information manager 1311 may store TAC information of a TAU request message requested by the terminal.

The resource information management unit 1313 manages resource information of the DU / RU.

The geographic information management unit 1315 of the RU manages the geographical location of the RU, connection information of the RUs, and coverage of the RU.

The femto AP information management unit 1317 manages the TAC of the femto AP related to handover with the RU. TAC of femtoAP may be obtained from femto gateway or MME.

The tracking area reconstruction unit 1330 receives a tracking area identifier list of the terminal 10 from the MME 200. The tracking area reconstruction unit 1330 reconstructs the tracking area identifier list of the terminal 10 received from the MME 200. The tracking area reconstruction unit 1330 generates a new tracking area identifier list of the terminal 10 by regrouping the RUs based on the information stored in the decision information management unit 1310.

The tracking area reconstruction unit 1330 is configured to track a tracking area identifier list managed by the MME based on a mobile path of a terminal, a radio / bearer resource allocated to a DU / RU / terminal, a continuous geographical section of RU coverage, and femto AP information. And change according to network situation.

The tracking area reconstruction unit 1330 transmits a TAU permission message including a new tracking area identifier list to the terminal 10.

The tracking area mapping storage unit 1350 maps and manages the tracking area identifier list of the MME and the reconfigured tracking area identifier list.

The paging unit 1370 is requested to transmit a paging message from the MME 200 to the terminal. The paging unit 1370 refers to the tracking area mapping storage unit 1350 and checks whether the tracking area identifier list of the terminal 10 received from the MME 200 is reconfigured. The paging unit 1370 searches for a cell included in the reconfigured tracking area identifier list and transmits a paging message only to the RU / DU related to the found cell.

Referring to FIG. 7, the MME 200 transmits a TAU Accept message to the tracking area management device 1300 (S210). The TAU Accept message contains a list of tracking area identifiers generated by the MME.

The tracking area management apparatus 1300 determines whether a change in the tracking area identifier list received from the MME 200 is necessary based on the terminal movement information and the network setting information (S220). The tracking area management apparatus 1300 extracts a new TAC related to the terminal based on the terminal movement information and the network setting information. The tracking area management apparatus 1300 compares the old TAC (old TAC) and the new TAC included in the tracking area identifier list received from the MME 200. If there is no new TAC or the new TAC is included in the existing TAC, the tracking area management device 1300 does not change the tracking area identifier list. If the new TAC includes a TAC that is not included in the existing TAC, the tracking area management apparatus 1300 determines that the tracking area identifier list needs to be changed.

When it is determined that the tracking area identifier list needs to be changed, the tracking area management apparatus 1300 generates a new tracking area identifier list based on the new TAC (S230). The tracking area management apparatus 1300 may determine the priority based on the weight of each information among the TACs extracted by the information of the determination information management unit 1310. The tracking area management apparatus 1300 generates a new tracking area identifier list including the number of TACs within a range that the terminal can receive.

The tracking area management apparatus 1300 transmits a new tracking area identifier list to the terminal 10 (S240). The tracking area identifier list is transmitted in a TAU Accept message.

The MME 200 requests the DU / RUs in the tracking area of the terminal 10 to transmit a paging message (S250).

The tracking area management apparatus 1300 selects a DU / RU corresponding to the new tracking area identifier list (S260).

The tracking area management device 1300 transfers the paging message only to the selected DU / RU (S270). Since the tracking area management apparatus 1300 manages all the DUs / RUs, the tracking area management apparatus 1300 may selectively transmit a paging message.

In order to deliver the data packet to the terminal in the idle mode, the MME requests a paging message for waking the terminal. The paging message is delivered to all tracking areas included in the tracking area identifier list where the terminal is located. Therefore, if the range of the tracking area is wide, the paging message generated in the radio section is increased.

However, the tracking area management apparatus 1300 generates a tracking area identifier list having a narrower range than the tracking area identifier list generated by the MME. Accordingly, the tracking area management apparatus 1300 may reduce the paging load.

In addition, since the tracking area management apparatus 1300 reconfigures the tracking area identifier list based on the information related to the terminal, it is possible to reduce the frequent TAU procedure of the terminal.

The embodiments of the present invention described above are not only implemented through the apparatus and the method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiments of the present invention or a recording medium on which the program is recorded.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims

In a network composed of at least one digital signal processing device and a plurality of wireless signal processing devices connected to each digital signal processing device, a tracking area management device manages a tracking area,

Receiving first tracking area information related to a terminal from a mobility management entity;

Changing the first tracking area information to second tracking area information based on at least one of movement information of the terminal and setting information of the network; and

Transmitting a tracking area update accept message including the second tracking area information to a wireless signal processing device to which the terminal is connected;

Tracking area management method comprising a.
In claim 1,

The tracking area information includes a tracking area identifier (TAI) list.
In claim 1,

The setting information of the network is

And at least one of connection information between the digital signal processing device and the wireless signal processing device, resource information between the digital signal processing device and the wireless signal processing device, and geographic information of the wireless signal processing device.
In claim 1,

And the second tracking area information includes a tracking area narrower than the first tracking area information.
In claim 1,

The step of changing to the second tracking area information

A tracking area management method of searching for a wireless signal processing device related to a moving path of the terminal based on the movement information of the terminal, and generating the second tracking area information including identification information of the found wireless signal processing device.
In claim 1,

The step of changing to the second tracking area information

Tracking tracking area code related to the terminal based on at least one of the movement information of the terminal and the configuration information of the network, and generates the second tracking area information including the extracted tracking area code. Zone management method.
In claim 1,

The step of changing to the second tracking area information

And tracking the wireless signal processing devices connected to a plurality of digital signal processing devices to generate the second tracking area information.
In a network composed of at least one digital signal processing device and a plurality of wireless signal processing devices connected to each digital signal processing device, a tracking area management device manages a tracking area,

Changing first tracking area information related to the terminal received from a mobility management entity to second tracking area information based on at least one of mobile terminal information and configuration information of the network;

Receiving a request to transmit a paging message of the terminal from the mobility management object to a tracking area included in the first tracking area information;

Finding the second tracking area information corresponding to the first tracking area information, searching for a cell included in the second tracking area, and

Transmitting a paging message to the digital signal processing apparatus and the wireless signal processing apparatus related to the found cell;

Tracking area management method comprising a.
In claim 8,

The tracking area information includes a tracking area identifier (TAI) list.
In claim 8,

The setting information of the network is

And at least one of connection information between the digital signal processing device and the wireless signal processing device, resource information between the digital signal processing device and the wireless signal processing device, and geographic information of the wireless signal processing device.
An apparatus for managing a tracking area in a network composed of at least one digital signal processing device and a plurality of wireless signal processing devices connected to each digital signal processing device,

A decision information management unit for managing movement information of the terminal and configuration information of the network; and

Receive first tracking area information related to a terminal from a mobility management entity, reconfigure the first tracking area information to second tracking area information based on the information of the determination information management unit, and connect the terminal to the terminal. Tracking area reconstruction unit for transmitting a tracking area update permission message including the second tracking area information to a wireless signal processing device

Tracking area management device comprising a.
In claim 11,

And a tracking area mapping storage unit for mapping and managing the first tracking area information and the second tracking area information.
In claim 11,

When the mobile management object is requested to transmit a paging message of the terminal to the tracking area included in the first tracking area information, the second tracking area information corresponding to the first tracking area information is retrieved, and the second tracking area information is retrieved. And a paging unit configured to transmit a paging message to the digital signal processing apparatus and the wireless signal processing apparatus included in the tracking area information.
In claim 11,

The tracking area information includes a tracking area identifier (TAI) list.
In claim 11,

The setting information of the network is

And at least one of connection information between the digital signal processor and the wireless signal processor, resource information between the digital signal processor and the wireless signal processor, and geographical information of the wireless signal processor.
In claim 11,

And the second tracking area information includes a tracking area narrower than the first tracking area information.
In claim 11,

The tracking area reconstruction unit

A tracking area management device searching for a radio signal processing device related to a movement path of the terminal based on the movement information of the terminal, and generating the second tracking area information including information of the found radio signal processing device.
In claim 11,

The tracking area reconstruction unit

A tracking area management device for generating the second tracking area information by tying wireless signal processing devices respectively connected to a plurality of digital signal processing devices.