KR102544506B1 - Method detecting position of user terminal for lte network - Google Patents

Abstract

In an LTE network positioning method according to an embodiment of the present invention, while a paging operation is being performed according to a request of a serving Mobility Management Entity (MME) that has received a positioning request for a terminal, a target MME is located in an area of the target MME. Receiving a location registration request of the terminal that has moved to ; Requesting, by the target MME, terminal information of the terminal from the serving MME according to the location registration request of the terminal; Receiving, by the target MME, a location positioning request for the terminal generated according to a location movement message of the serving MME having received the terminal information; and requesting, by the target MME, paging to an Evolved Node B (eNB) in which the terminal is registered.

Description

Positioning method of LTE network {METHOD DETECTING POSITION OF USER TERMINAL FOR LTE NETWORK}

The present invention relates to a positioning method of an LTE network, and more particularly, to a positioning method of an LTE network capable of reducing a failure probability of positioning of a terminal.

The 3rd Generation Partnership Project (3GPP) mobile communication system based on WCDMA (Wideband Code Division Multiple Access) radio access technology is widely deployed around the world and can be defined as the first evolutionary step of WCDMA. High Speed Downlink Packet Access (HSDPA) provides a highly competitive radio access technology to a 3GPP mobile communication system in the mid-term future.

However, since the requirements and expectations of users and service providers are constantly increasing and competition for developing wireless access technologies continues, new technological evolution is required in 3GPP mobile communication systems in order to have competitiveness in the future.

That is, reduction in cost per bit, increase in service availability, flexible use of frequency bands, simple structure and open interface, and appropriate power consumption of user equipment are required. In addition, prevention of unnecessary latency in network nodes and efficient use of network resources may also promote technological evolution in 3GPP.

And, in 3GPP Release 8, as one of the mobile communication systems to satisfy the above-mentioned requirements, a network architecture, Evolved Packet Core (EPC) is described. EPC is a set of network nodes for 3GPP LTE system. EPC has evolved from the Core Network of the existing 3GPP system architecture, supports E-UTRAN, etc., an evolved radio access network, and is an efficient, simplified network node to increase the efficiency of packet networks. have a network structure. A wireless communication system including an EPC and an Evolved-UMTS Terrestrial Radio Access Network (E-UTRAN) may be referred to as an Evolved Packet System (EPS), and an LTE mobile communication system currently being implemented and serviced in Korea corresponds to this.

In the LTE network, a radio resource of a UE is released from a UE (User Equipment) to eNodeB (eNB: base station) to SGW (Serving Gateway) section if there is no transmission/reception traffic to the UE for a certain period of time. This is to increase efficiency by enabling a plurality of terminals to share radio resources in a time-division manner. In this case, the corresponding terminal can be said to have entered an idle state.

As such, when a terminal enters an idle state, a downlink bearer toward the corresponding terminal becomes inactive. Here, the bearer means a kind of data transmission channel.

Meanwhile, the location of the terminal in the LTE network can be estimated from the location of the base station to which the terminal is connected, and the EPC determines the location of the terminal in units of MME (Mobility Management Entity). When a positioning request for the terminal occurs, a signal is transmitted to base stations managed by the MME where the terminal registered the location last, and it is determined which base station the terminal is connected to. At this time, when a terminal in an idle state moves from an MME boundary area, that is, when it moves to an area corresponding to an MME other than the last location-registered MME, a phenomenon in which positioning of the terminal fails may occur.

An object of the present invention is to provide a location positioning method of an LTE network capable of reducing a phenomenon in which positioning of a terminal fails when a positioning request occurs.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

In order to solve the above technical problem, a location positioning method of an LTE network according to an embodiment of the present invention performs a paging operation according to a request of a serving Mobility Management Entity (MME) that has received a location positioning request for a terminal. Among them, the step of receiving, by the target MME, a location registration request of the terminal that has moved to the area of the target MME; Requesting, by the target MME, terminal information of the terminal from the serving MME according to the location registration request of the terminal; Receiving, by the target MME, a location positioning request for the terminal generated according to a location movement message of the serving MME having received the terminal information; and requesting, by the target MME, paging to an Evolved Node B (eNB) in which the terminal is registered.

According to the embodiment, the target MME may further include recognizing the serving MME based on the IP address of the serving MME included in the location registration request of the terminal.

According to the embodiment, after transmitting the location registration request of the terminal to a Home Subscriber Server (HSS), the target MME recognizing the serving MME based on the IP address of the serving MME included in the response from the HSS may further include.

Depending on the embodiment, the step of receiving, by the target MME, a response to the paging message transmitted through the eNB by the terminal receiving the paging message from the eNB; and performing, by the target MME, location determination by locating the terminal based on the response.

According to an embodiment, the positioning may be performed using any one of a cell ID (CID) method, an enhanced cell ID (E-CID) method, and an observed time difference of arrival (OTDOA) method.

A location location method of an LTE network according to another embodiment of the present invention includes the steps of a serving MME (Mobility Management Entity) receiving a location location request for a UE and requesting paging to an Evolved Node B (eNB) in which the UE has registered a location. ; Receiving, by the serving MME, a request for terminal information of the terminal generated according to a location registration request of the terminal that has moved from the target MME to the area of the target MME while a paging operation according to the request is being performed; and transmitting, by the serving MME, a location movement message indicating that the terminal has moved to an area of the target MME upon receiving the request for the terminal information, to a gateway mobile location center (GMLC).

In an LTE network location location method according to another embodiment of the present invention, a serving Mobility Management Entity (MME) receives a location location request for a UE and requests paging to an Evolved Node B (eNB) in which the UE has registered a location. doing; receiving, by a target MME, a location registration request of the terminal that has moved to an area of the target MME while a paging operation according to the paging request is being performed; Receiving, by the serving MME, a request for terminal information of the terminal generated according to a location registration request of the terminal; Transmitting, by the serving MME, a location movement message notifying that the terminal has moved to an area of the target MME to a Gateway Mobile Location Center (GMLC) upon receiving the request for terminal information; Receiving, by the target MME, a location positioning request for the terminal generated according to the location movement message; and requesting, by the target MME, paging to an eNB to which the terminal is registered.

According to the location positioning method of an LTE network according to an embodiment of the present invention configured as described above, even when a terminal moves from the MME boundary while performing a paging operation in response to a positioning request, the terminal recognizes the position movement of the terminal and informs the moved terminal. It is possible to reduce the possibility of positioning failure by performing a paging operation on the .

The effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. will be.

1 is a configuration diagram of an LTE network according to the present invention.
2 is a diagram for explaining a problem that occurs when positioning a terminal.
3 is a flowchart illustrating a location determination method of an LTE network according to an embodiment of the present invention.

Hereinafter, at least one embodiment related to the present invention will be described in more detail with reference to the drawings. The suffixes "module" and "unit" for components used in the following description are given or used together in consideration of ease of writing the specification, and do not have meanings or roles that are distinct from each other by themselves.

1 is a configuration diagram of an LTE network according to the present invention.

Referring to FIG. 1, an LTE network 1 includes a user equipment (UE) 10, an evolved node B (eNB) 20), a serving gateway (S-GW) 30, and a packet packet (P-GW). Data Network Gateway, 40), MME (Mobility Management Entity, 50), GMLC (Gateway Mobile Location Center, 60), HSS (Home Subscriber Server, 70), AGENT (80) and eSMLC (evolved Serving Mobile Location Center, 90) It can be configured to include.

The UE 10 is an LTE user terminal and is connected to the eNB 20 through the LTE-Uu interface 15. Here, the LTE Uu interface 15 is a radio interface, and a control plane for transmitting and receiving control messages and a user plane for providing user data are defined.

The eNB 20 is a device that provides a radio interface to the UE 10, and provides radio resource management functions such as radio bearer control, radio admission control, dynamic radio resource allocation, load balancing, and inter-cell interference control. do.

The S-GW 30 is an end of an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) and an Evolved Packet Core (EPC), and serves as an anchoring point during handover between eNBs 20 and handover between 3GPP systems. do. Here, the E-UTRAN is composed of at least one eNB 20, and the EPC includes the S-GW 30, the P-GW 40, the MME 50, the GMLC 60, the HSS 70, and the eSMLC ( 90).

The P-GW 40 connects the UE 10 to an external Packet Data Network (PDN) 110 and performs a packet filtering function. In addition, the P-GW 40 allocates an IP address to the UE 10 and operates as a mobility anchoring point during handover between a 3GPP system and a non-3GPP system. In particular, the P-GW 40 receives a Policy and Charging Control (PCC) rule from a Policy and Charging Rule Function (PCRF), applies it to a corresponding service flow, and UE 10/Service Date Flow (SDF). Provide billing function. The PCRF is an entity that performs policy and billing control, and provides policy control decision and billing control functions.

The MME 50 is a node that manages the mobility of the UE 10, and may be in charge of session management, idle subscriber management, paging, and subscriber authentication functions. That is, the MME 50 may be in charge of various functions of the control plane for processing control signals when there is a request for association or a request for radio bearer setup from the UE 10 or another network node, which will be described later. It is possible to perform functions such as setup of an EPS bearer or IP tunnel, mobility management, etc. by receiving user profile information, authentication and location-related data from the HSS 70.

The MME 50 may recognize the location of the UE in units of cells when the UE 10 is in an active state, that is, in a communication state, and the eNB 20 installed in the cell in which the UE 10 is located is aware of information about In addition, upon receiving a location positioning request from the GMLC 60, the MME 50 requests a paging to the eNB 20 installed in the cell when recognizing the cell in which the UE 10 is located, and the UE 10 If the location cell is not recognized, paging may be requested to all eNBs 20 managed by the MME 50 .

Here, the paging operation refers to an operation of calling a corresponding terminal when an incoming call (eg, data reception, location positioning request) occurs to the corresponding terminal, and a predetermined number of times at a predetermined time interval during a predetermined paging time, n ( n is an integer greater than or equal to 1) means an operation of transmitting a paging message as many times as possible. Upon receiving the paging message, the UE transmits a response to the paging message to the eNB 20, and the eNB 20 that receives the paging message transmits the response to the MME 50 so that the MME 50 can determine the location of the UE.

When the MME 50 detects the location of the terminal, the MME 50 performs location positioning in conjunction with the eSMLC 90, and transmits location information on the exact location of the terminal to the position location request of the GMLC 60. can be sent in response.

Here, the MME 50 performs location positioning in conjunction with the eSMLC 90, such as a CID (Cell ID) method, an E-CID (Enhanced Cell ID) method, an OTDOA (Observed Time Difference of Arrival) method, and the like. can be used

If the MME 50 cannot determine the location of the UE, the MME 50 may transmit a location failure message indicating that the location of the corresponding UE has failed in response to the location location request of the GMLC 60.

The GMLC (60) receives a positioning request from the AGENT (80), transmits an MME information request including user information (eg, subscriber number) to the HSS (70), and responds to the user information from the HSS (70) It is possible to receive MME information to identify the MME 50 corresponding to the MME information. The GMLC 60 transmits a location location request to the identified MME 50, and according to the results of paging and location location of the MME 50, the location information of the UE 10 or a location location failure message is sent to the AGENT 80 for location location It can be sent in response to a request.

The HSS 70 is a central database for storing subscriber profiles, and provides user authentication information and user profiles to the MME 50 . In addition, the HSS 70 may store MME information, which is information about the MME 50 to which the UE 10 has last registered, and may provide the MME information to the GMLC 60 at the request of the GMLC 60. there is.

The AGENT 80 may receive a request for locating an external UE 10 and transmit a location location request including user information (eg, subscriber number) of the UE 10 to the GMLC 60 .

The eSMLC 90 may perform positioning of the UE 10 according to the request of the MME 50, generate location information on the exact location of the corresponding UE 10, and provide it to the MME 50. As described above, a CID method, an E-CID method, an OTDOA method, or the like may be used for positioning.

The PDN 110 refers to a network connected to an end user communicating with the UE 10 .

Hereinafter, an interface between elements constituting the LTE network 1 will be briefly described.

LTE-Uu (15) provides a control plane and a user plane as a radio interface between the UE (10) and the eNB (20).

The S1-U 25 is an interface between the eNB 20 and the S-GW 30 and provides a user plane. At this time, GTP (GPRS Tunneling Protocol) tunneling (GTP-U) for each bearer is provided.

X2 26 is an interface between two eNBs 20 and provides a control plane and a user plane. In the control plane, the X2-AP protocol is used, and in the user plane, GTP tunneling per bearer is provided for data forwarding during X2 handover.

S5 35 is an interface between the S-GW 30 and the P-GW 40 and provides a control plane and a user plane. At this time, the user plane provides GTP tunneling (GTP-U) for each bearer, and the control plane provides GTP tunnel management (GTP-C).

The SGi 45 is an interface between the P-GW 40 and the PDN 110 and defines a user plane and a control plane. In the user plane, an IETF-based IP packet forwarding protocol is used, and in the control plane, protocols such as DHCP and RADIUS/Diameter are used.

S11 55 is an interface between the MME 50 and the S-GW 30, a control plane is defined, and GTP tunneling is provided for each bearer.

The S1-MME 75 is an interface between the eNB 20 and the MME 50, a control plane is defined, and the S1-AP protocol is used.

2 is a diagram for explaining a problem that occurs when positioning a terminal.

Referring to FIG. 2 , a first area A1 and a second area A2 are illustrated. The first area A1 refers to an area managed by a serving MME (50-1 in FIG. 3), and the second area A2 refers to an area managed by a target MME 50-2. it means. Here, the serving MME 50-1 refers to an MME that manages an eNB to which the UE 10 is connected before movement, and the target MME 50-2 refers to an MME that manages an eNB to which the UE 10 is connected after movement. means

Although only two eNBs 20 are illustrated in FIG. 1 for convenience of description, for example, various multimedia services including communication services (eg, voice services, video services, additional information services, etc.) for hundreds to thousands of eNBs. service) can be controlled by one MME 50, dozens of eNBs form one TA (Tracking Area) area, and several to dozens of TA areas are controlled by one MME 50. can be managed

The UE 10 is located at the first point P1 in the first area A1 at the first time point, moves after the first time point, and moves to the second point P2 in the second area A2 at the second time point. ) is assumed to be located at

When the UE 10 in an idle state moves to the second area A2 while the UE 10 is attempting paging according to a positioning request for the UE 10 after the first time point, the serving MME 50- 1) does not know the movement of the UE 10, and the paging fails (response not received). Accordingly, the positioning failure message is transmitted to the AGENT 80 through the GMLC 60, and finally positioning of the UE 10 fails.

If the UE 10 moves in an active state rather than an idle state, the UE 10 performs a handover procedure, and the serving MME 50-1 transmits the UE (50-1) through the handover request message received at this time. 10) is informed of the movement.

That is, when the UE 10 in an idle state moves in the MME boundary area, a location location failure may occur due to a paging failure.

3 is a flowchart illustrating a location determination method of an LTE network according to an embodiment of the present invention.

Referring to FIG. 3, the current UE 10 is located at a first point P1 and refers to an eNB of a cell to which the first point P1 belongs as a serving eNB 20-1 or a first eNB, and a serving eNB ( 20-1) is referred to as the serving MME 50-1 or the first MME. After step S60, the UE 10 is located at the second point P2 and refers to the eNB of the cell to which the second point P2 belongs as the target eNB 20-2 or the second eNB, and the target eNB 20-2 The MME that manages is referred to as the target MME 50-2 or the second MME. It is also assumed that the UE 10 is in an idle state.

The AGENT 80 may receive a request for location determination of an external UE 10 and transmit a location location request including user information (eg, subscriber number) of the UE 10 to the GMLC 60 (S10 ).

The GMLC 60 may receive a positioning request from the AGENT 80 and transmit an MME information request including user information to the HSS 70 (S20). The MME information request is a message requesting which MME the UE 10 is currently registered with.

The HSS 70 searches for the MME 50-1 to which the UE 10 has last registered a location based on user information corresponding to the UE 10, and MME information about the MME 50-1 (eg, MME IP address) to the GMLC 60 (S30).

The GMLC 60 may transmit a positioning request for the UE 10 to the serving MME 50-1 identified based on the MME information (S40).

The serving MME 50-1 may request to perform a paging operation on the serving eNB 20-1 to which the UE 10 is registered (S50).

During the paging operation, the UE 10 moves from the first point P1 to the second point P2 (S60). That is, the UE 10 cannot transmit a response to paging by the serving eNB 20-1.

The UE 10 may request location registration to the target MME 50-2 through the target eNB 20-2 (S70).

According to the location registration request of the UE 10, the target MME 50-2 recognizes that the MME to which the UE 10 is last located is the serving MME 50-1, and returns to the serving MME 50-1. Terminal information of the UE 10 may be requested (S80).

According to an embodiment, the target MME 50-2 is based on the information (eg, IP address) of the serving MME 50-1 included in the location registration request from the UE 10, so that the UE 10 Finally, it is possible to recognize that the location-registered MME is the serving MME 50-1.

According to another embodiment, the target MME 50-2 receives the location registration request from the UE 10, forwards the location registration request to the HSS 70, and then the serving MME included in the response from the HSS 70. Based on the information (eg, IP address) of (50-1), the UE (10) can recognize that the last location-registered MME is the serving MME (50-1).

The serving MME 50-1 may receive the UE information request for the UE 10 from the target MME 50-2 and recognize the location movement of the UE 10 (S90).

At this time, the serving MME 50-1 recognizing the movement of the location of the UE 10 may ignore it even if it receives a message from the serving eNB 20-1 indicating that paging for the UE 10 currently being performed has failed. there is.

The serving MME 50-1 sends a location movement message notifying that the UE 10 has moved from the area managed by the serving MME 50-1 to the area managed by the target MME 50-2 to the GMLS 60. It can be transmitted (S100). The location movement message may include the IP address of the target MME 50 - 2 in the area to which the UE 10 has moved.

The GMLC 60 may transmit a location positioning request for the UE 10 to the target MME 50-2 based on the location movement message notifying the movement of the UE 10 received from the serving MME 50-1. Yes (S110).

The target MME 50-2 may request the target eNB 20-2 to which the UE 10 is registered to perform a paging operation (S120).

Upon receiving the paging message from the target eNB 20-2, the UE 10 transfers a response to the paging message to the target MME 50-2 through the target eNB 20-2, and the target MME 50-2 ) can determine the location of the UE 10 (S130).

When the target MME 50-2 detects the location of the UE 10, the target MME 50-2 may perform location positioning in conjunction with the eSMLC 90 to generate location information of the UE 10. Yes (S140).

The target MME 50-2 transmits the location information of the UE 10 in response to the location location request of the GMLC 60, and the GMLC 60 transmits the location information of the UE 10 to the location of the AGENT 80. It can be transmitted in response to a positioning request.

According to the location positioning method of an LTE network according to an embodiment of the present invention, even when a terminal moves from an MME boundary while performing a paging operation in response to a location positioning request, a paging operation is performed for the terminal that has moved by recognizing the location movement of the terminal. Thus, it is possible to reduce the possibility of positioning failure.

The method described above can be implemented as computer readable codes on a computer readable recording medium. Computer-readable recording media includes all types of recording media in which data that can be decoded by a computer system is stored. For example, there may be read only memory (ROM), random access memory (RAM), magnetic tape, magnetic disk, flash memory, optical data storage device, and the like. In addition, the computer-readable recording medium may be distributed to computer systems connected through a computer communication network, and stored and executed as readable codes in a distributed manner.

In addition, although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art can make the present invention within the scope not departing from the spirit and scope of the present invention described in the claims below. It will be appreciated that various modifications and variations may be made.

Claims (14)

While a paging operation is being performed by the serving Evolved Node B (eNB) in which the location of the UE is registered according to the request of the serving Mobility Management Entity (MME) that has received the location positioning request for the UE, the target MME selects the target MME. Receiving a location registration request of the terminal that has moved to an area of;
Requesting, by the target MME, terminal information of the terminal from the serving MME according to the location registration request of the terminal;
Receiving, by the target MME, a location positioning request for the terminal generated according to a location movement message of the serving MME having received the terminal information; and
The target MME requesting paging to a target eNB to which the terminal is registered. According to claim 1,
The target MME further comprising recognizing the serving MME based on the IP address of the serving MME included in the location registration request of the terminal. According to claim 1,
After transmitting the location registration request of the terminal to a Home Subscriber Server (HSS), the target MME recognizing the serving MME based on the IP address of the serving MME included in the response from the HSS LTE further comprising A method for positioning the network. According to claim 1,
Receiving, by the target MME, a response to the paging message transmitted through the target eNB by the UE having received the paging message from the target eNB; and
The method of location determination of the LTE network, further comprising the step of the target MME, locating the terminal based on the response and performing location positioning. According to claim 4,
The positioning method of the LTE network is performed using any one of a CID (Cell ID) method, an E-CID (Enhanced Cell ID) method, and an OTDOA (Observed Time Difference of Arrival) method. Requesting, by a serving Mobility Management Entity (MME), a paging request to an Evolved Node B (eNB) in which the UE has registered a location by receiving a location positioning request for the UE;
While a paging operation is performed by the eNB according to the request, the serving MME receives a request for terminal information of the terminal generated according to a location registration request of the terminal that has moved from the target MME to the area of the target MME. step; and
Upon receiving the request for the terminal information, the serving MME transmits a location movement message indicating that the terminal has moved to an area of the target MME to a Gateway Mobile Location Center (GMLC). . According to claim 6,
The request for terminal information of the terminal is transmitted to the serving MME based on the IP address of the serving MME included in the location registration request of the terminal. According to claim 6,
The request for terminal information of the terminal is transmitted to the serving MME based on the IP address of the serving MME included in the response from the HSS after transmitting the location registration request of the terminal to the Home Subscriber Server (HSS). A method for positioning the network. Requesting, by a serving Mobility Management Entity (MME), a paging request to a serving Evolved Node B (eNB) to which the UE has registered a location by receiving a positioning request for the UE;
Receiving, by a target MME, a location registration request of the terminal that has moved to an area of the target MME while a paging operation is being performed by the serving eNB according to the paging request;
Receiving, by the serving MME, a request for terminal information of the terminal generated according to a location registration request of the terminal;
Transmitting, by the serving MME, a location movement message notifying that the terminal has moved to an area of the target MME to a Gateway Mobile Location Center (GMLC) upon receiving the request for terminal information;
Receiving, by the target MME, a location positioning request for the terminal generated according to the location movement message; and
The method of location positioning in an LTE network comprising the step of requesting, by the target MME, paging to a target eNB to which the terminal is registered. According to claim 9,
The target MME further comprising recognizing the serving MME based on the IP address of the serving MME included in the location registration request of the terminal. According to claim 9,
After the target MME transmits the location registration request of the terminal to a Home Subscriber Server (HSS), recognizing the serving MME based on the IP address of the serving MME included in a response from the HSS Further comprising Positioning method of LTE network. According to claim 9,
Receiving, by the target MME, a response to the paging message transmitted through the target eNB by the UE having received the paging message from the target eNB; and
The method of location determination of the LTE network, further comprising the step of the target MME, locating the terminal based on the response and performing location positioning. According to claim 12,
The positioning method of the LTE network is performed using any one of a CID (Cell ID) method, an E-CID (Enhanced Cell ID) method, and an OTDOA (Observed Time Difference of Arrival) method. According to claim 9,
Wherein the location movement message includes the IP address of the target MME.

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