KR20150064783A - Method and apparatus for prohibitting unneceassary handover in mobile communication system - Google Patents

Abstract

The present invention provides a method for prohibiting unnecessary handovers in a mobile communications system by a base station. The method comprises the steps of: exchanging information on public land mobile network (PLMN) between the neighboring base station and the terminal; determining whether a handover of a terminal to a neighboring base station is able to be performed, based on the information on PLMN of the terminal; stopping the handover of the terminal to the neighboring base station if the handover is unable to be performed; and performing the handover to the neighboring base station if the handover is able to be performed.

Description

TECHNICAL FIELD [0001] The present invention relates to a method and apparatus for preventing unnecessary handover in a mobile communication system,

The present invention relates to public land mobile network (PLMN) information exchange in a mobile communication system.

In order to provide a communication service by sharing a cell among a plurality of carriers or to stop providing a communication service of a specific provider in a specific cell, a plurality of carriers, such as those defined in 3GPP RRC (3 ^rd Generation Partnership Project Radio Resource Control) The reservedforoperatoruse IE value can be adjusted for the corresponding PLMN in System Information Block 1.

When a specific business operator operates the PLMN for testing without affecting existing commercial services during the cell sharing interworking test, the specific business entity can perform the following operations. The specific service provider can block the UE camping on the cell by broadcasting the test PLMNs after setting the PLMNs in the cellReservedForOperatorUse IE of system information block type 1. For blocking, the ENUMERATED value is set to reserved in cellReservedForOperatorUse IE.

Or, the provider B sharing the base station equipment of the provider A and setting the reserved foroperatoruse IE field for the PLMN of the provider A that the provider B who has acquired the frequency use right should broadcast in the standard specification, Can be limited. For this purpose, the specific service provider may block the UE camping on the cell by broadcasting the PLMNs after setting the PLMNs in the cellReservedForOperatorUse IE of system information block type 1. For blocking, the ENUMERATED value is set to reserved in cellReservedForOperatorUse IE.

After receiving a broadcast message in a specific cell, the UE in the idle state determines whether there is a PLMN that can camp on the broadcast message. If the UE finds a PLMN that can camp on, the UE may determine whether the PLMN is reserved for use by a particular provider before camping on the cell, and stop the access to the restricted PLMN of the corresponding cell. However, this is limited only when the UE initially accesses the cell in the idle state, and is not used for handover purposes.

If the handover is attempted from the target cell to the restricted PLMN, the source cell transmits a handover preparation request to the target cell every time, Must transmit a handover preparation failure according to the result of the specific PLMN connection restriction determination every time.

When the base stations of the corresponding cell exchange the broadcast PLMN list using the Served cell information in the X2 setup request / response and the ENB configuration update procedure, connection permission information is not exchanged for each PLMN of the corresponding UE.

Accordingly, if the source base station transmits the X2 Handover Request to the target base station and the source base station receives the preparation failure from the target base station as a result of performing the Connection Admission Control (CAC) of the target base station, It is possible to block a handover access attempt to the restricted PLMN.

However, the signaling for handover failure processing occurs very frequently in a region where mobility of the UE is large, which may cause unnecessary communication load between the BSs.

Accordingly, it is an object of the present invention to provide a method and apparatus for preventing unnecessary handover in a mobile communication system.

It is another object of the present invention to provide a method and apparatus for preventing unnecessary handover attempts to a terminal of a base station by allowing information on a service provider reserved for use in a mobile communication system to be shared among the base stations.

It is another object of the present invention to provide a method and apparatus for reducing unnecessary signaling between base stations by allowing information on a service provider reserved for use in a mobile communication system to be shared among base stations.

It is another object of the present invention to provide a method and apparatus for providing a control message for sharing information about a service provider reserved for use in a mobile communication system between base stations.

According to a first aspect of the present invention, there is provided a method of a base station for preventing unnecessary handover in a mobile communication system, the method comprising: exchanging information on a PLMN of a neighboring BS and a UE; Determining whether handover to the neighboring base station is possible based on information on the handover of the mobile station, stopping the handover to the neighboring base station of the mobile station when the handover is impossible, And performing a handover to the neighboring BS from the MS.

According to a second aspect of the present invention, there is provided an apparatus for preventing unnecessary handover in a mobile communication system, the apparatus comprising: at least one processor; a memory; a neighboring base station; And at least one program stored in the memory and being driven by the one or more processors, the program being capable of performing handover to the neighboring base station of the terminal based on information on the PLMN of the terminal And stops the handover to the neighboring base station of the terminal when the handover is impossible, and proceeds the handover of the terminal to the neighboring base station when the handover is possible.

The present invention has an advantage in that it can reduce unnecessary handover attempts to a terminal of a base station by allowing information on a service provider reserved for use in a mobile communication system to be shared among base stations and to reduce unnecessary signaling between base stations There is an advantage to be connected.

1 is a first message flow diagram illustrating a PLMN reservation information providing procedure of a base station according to an embodiment of the present invention.
2 is a second message flow diagram illustrating a process of providing PLMN reservation information of a base station according to an embodiment of the present invention.
3 is a message flow diagram illustrating a process of receiving an X2 SETUP REQUEST message and an X2 SETUP RESPONSE message according to an embodiment of the present invention.
4 is a message flow diagram illustrating an ENB CONFIGURATION UPDATE and ENB CONFIGURATION UPDATE ACKNOWLEDGE message reception process according to an embodiment of the present invention.
5 is a flowchart for determining a handover-enabled PLMN in a base station according to an embodiment of the present invention.
6 is a block diagram of a base station according to an embodiment of the present invention.
7 is a detailed block diagram of a base station according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions of the present invention and may vary depending on the terminal, the operator's intention or custom. Therefore, the definition should be based on the contents throughout this specification.

Hereinafter, the present invention will be described with respect to a method and an apparatus for preventing unnecessary handover attempts to a terminal of a base station by allowing information on a service provider reserved for use in a mobile communication system to be shared among base stations.

In order to reduce unnecessary base station handover attempts, the present invention proposes a method of transmitting cell information to a serving cell information IE included in a X2 SETUP REQUEST / RESPONSE message and an ENB CONFIGURATION UPDATE / ACKNOWLEDGE message transmitted / Add the for operator use field as shown in the table below.

<Table 1>

In order to notify the neighboring base station that the specific PLMN is reserved, the base station indicates to the cellReservedForOperatorUse IE that the PLMN having the PLMN identity is reserved, indicating that it is reserved. Not reserved indicates that no reservation is made.

Thereafter, the BS receives the Measurement Report from the UE, determines a handover target cell, and determines whether the corresponding PLMN of the UE is reserved in the target cell. If the corresponding PLMN is reserved, the base station does not perform the handover attempt of the UE.

1 is a first message flow diagram illustrating a PLMN reservation information providing procedure of a base station according to an embodiment of the present invention.

Referring to FIG. 1, the source cell 150 and the target cell 160 perform an X2 SETUP process or an eNB CONFIGURATION UPDATE process (step a). Here, the source cell 150 exchanges the Served Cell information IE with the target cell 160.

The Served Cell information IE indicates cell information required by the base station for the X2 interface. The Served Cell information IE includes Broadcast PLMNs.

In addition, in the present invention, the base station adds a cellReservedForOperatorUse IE after the corresponding PLMN identity of the broadcast PLMNs to set reserved if the PLMN is reserved, sets notReserved if the PLMN is not reserved, . In FIG. 1, it is assumed that PLMN A is reserved in the target cell 160 in one embodiment.

Then, the source cell 150 can recognize that the PLMN A is reserved in the target cell 160 through the broadcast PLMNs received from the target cell 160 (step b).

If the terminal 100 receiving the communication service by the PLMN A camps on the source cell 150 (step c), the terminal 100 transmits a handover to the source cell 150 through the Measurement Report for the target cell 160 The case of triggering can be considered (step d).

In this case, the source cell 150 can determine which of the PLMNs of the target cell 160 can be handed over to the PLMN in the handover determination process. 1, since the PLMN A of the target cell 160 is reserved, the UE 100 can not perform handover to the PLMN A of the target cell 160.

Accordingly, the source cell 150 recognizes that the handover to the PLMN A of the target cell 160 of the UE 100 is impossible and determines handover to the target cell 160 of the UE 100 e step). In this handover determination process, handover for a call for emergency services such as 119 and 112 is possible regardless of the PLMN in which the terminal 100 is registered.

In the present invention, the source cell 150 may determine whether an equivalent PLMN (EPLMN: Equivalent PLMN) equivalent to the PLMN A exists when the PLMN A is reserved in the target cell 160. In the equivalent PLMN, a plurality of providers existing in each country form a relationship with another PLMN according to a new business relationship and display a PLMN assigned the same priority. The equivalent PLMN is transmitted from the network to the UE after the registration procedure for a circuit network or a packet network, and may be utilized at the time of reselection of the UE.

The source cell 150 determines an equivalent PLMN that can be handed over and is not reserved when the PLMN A is reserved and the terminal 100 can not perform handover to the target cell 160 and transmits the determined equivalent PLMN to the terminal 100. [ Can be determined.

In this handover determination process, handover for a call for emergency services such as 119 and 112 is possible regardless of the PLMN in which the terminal 100 is registered.

2 is a second message flow diagram illustrating a process of providing PLMN reservation information of a base station according to an embodiment of the present invention.

Referring to FIG. 2, the source cell 250 and the target cell 260 perform an X2 SETUP process or an eNB CONFIGURATION UPDATE process (step a). Here, the source cell 250 exchanges the Served Cell information IE with the target cell 260.

The Served Cell information IE indicates cell information required by the base station for the X2 interface. The Served Cell information IE includes Broadcast PLMNs.

In addition, in the present invention, the base station adds a cellReservedForOperatorUse IE after the corresponding PLMN identity of the broadcast PLMNs to set reserved if the PLMN is reserved, sets notReserved if the PLMN is not reserved, . In FIG. 2, it is assumed that PLMN A is not reserved in the target cell 260, in one embodiment. Then, the source cell 250 can recognize that the PLMN A is reserved in the target cell 260 through the broadcast PLMNs received from the target cell 260 (step b). When the terminal 200 receiving the communication service by the PLMN A camps on the source cell 250 (step c), the terminal 200 transmits a handover to the source cell 250 through the Measurement Report for the target cell 260 The case of triggering can be considered (step d).

In this case, in the handover determination process, the source cell 250 can determine which of the PLMNs of the target cell 260 can be handed over by the UE 200. [ In FIG. 1, since the PLMN A of the target cell 260 is not reserved, the UE 200 can perform handover to the PLMN A of the target cell 260. Accordingly, the source cell 250 recognizes handover to the PLMN A of the target cell 260 of the UE 200 and determines handover to the target cell 260 of the UE 200 (step e ). In this handover decision process, a handover for a call for an emergency service such as 119, 112, etc. is possible regardless of the PLMN in which the terminal 200 is registered. Thereafter, the source cell 250 and the target cell 260 perform a handover procedure for the terminal 200 (step f).

3 is a message flow diagram illustrating a process of receiving an X2 SETUP REQUEST message and an X2 SETUP RESPONSE message according to an embodiment of the present invention.

Referring to FIG. 3, the eNB 1 (eNode B) 310 and the eNB2 320 transmit and receive the X2 SETUP REQUEST message and the X2 SETUP RESPONSE message to each other (steps a and b). The X2 SETUP REQUEST message and the X2 SETUP RESPONSE message are transmitted to the base station eNB1 310 and the eNB2 320 at the X2 interface which is an interface between the base stations eNB1 310 and eNB2 320, level configuration data) to facilitate interoperability on the X2 interface. After the message transmission / reception process, the base station updates the existing application level configuration data with the newly received application level configuration data. In the message transmission / reception process, the base station transmits / receives a list of Served Cells in the X2 SETUP REQUEST message and the X2 SETUP RESPONSE message. In the present invention, the base station transmits and receives the Served Cell Information IE by including it in the X2 SETUP REQUEST message and the X2 SETUP RESPONSE message. The Served Cell information IE indicates cell information required by the base station for the X2 interface. The Served Cell information IE includes Broadcast PLMNs. In addition, in the present invention, the base station adds a cellReservedForOperatorUse IE after the corresponding PLMN identity of the broadcast PLMNs to set reserved if the PLMN is reserved, sets notReserved if the PLMN is not reserved, .

4 is a message flow diagram illustrating an ENB CONFIGURATION UPDATE and ENB CONFIGURATION UPDATE ACKNOWLEDGE message reception process according to an embodiment of the present invention. Referring to FIG. 3, the eNB 1 (eNode B) 410 and the eNB2 420 transmit and receive the ENB CONFIGURATION UPDATE and ENB CONFIGURATION UPDATE ACKNOWLEDGE messages to each other (steps a and b). The ENB configuration update and the ENB configuration update ACKNOWLEDGE messages are transmitted to the base stations eNB1 410 and eNB2 420 at the X2 interface and the base stations eNB1 410 and eNB2 420 at the application level configuration level configuration data to the newly received application level configuration data by exchanging existing application level configuration data with the application level configuration data. In the message transmission / reception process, the base station transmits a list of Served Cells to the ENB CONFIGURATION The Served Cell Information IE is transmitted to the base station through the X2 interface, and the Served Cell Information IE is transmitted to the base station through the X2 interface. In this case, the base station transmits the Served Cell Information IE in the ENB CONFIGURATION UPDATE message and the ENB CONFIGURATION UPDATE ACKNOWLEDGE message. And the cell information required for the cell. In addition, in the present invention, the base station adds cellReservedForOperatorUse IE to the corresponding PLMN identity of the broadcast PLMNs to set reserved when the PLMN is reserved, and when the PLMN is reserved If not, you can set notReserved to indicate that the PLMN is reserved.

5 is a flowchart for determining a handover-enabled PLMN in a base station according to an embodiment of the present invention.

5, it is assumed that a base station of a source cell receives a Served Cell Information IE including a cellReservedForOperatorUse IE indicating whether a specific PLMN is reserved from a neighboring base station (for example, a target cell base station). In addition, it is assumed that a terminal transmitting the Measurement Report exists in the base station of the source cell.

Thereafter, the BS examines the cellReservedForOperatorUse IE to set an un-reserved BPLMN to an available BPLMN (step 505).

That is, the BS sets the BPLMN with the cellReservedForOperatorUse IE included in the Served Cell Information IE of the ENB CONFIGURATION UPDATE or X2 SETUP REQUEST message set to notReserved to the available BPLMN. Here, BPLMN denotes a broadcast PLMN.

Thereafter, the BS determines whether a serving PLMN of the UE is included in an available PLMN of the target cell (step 510)

If the serving PLMN of the UE is included in the available PLMN of the target cell (step 510), the BS attempts handover of the UE to the serving PLMN of the neighbor BS in step 515.

If the serving PLMN of the UE is not included in the available PLMN of the target cell (step 510), the BS determines whether the EPLMN of the UE is included in the available PLMN of the target cell (operation 520).

If the EPLMN of the UE is included in the available PLMN of the target cell (step 520), the BS attempts handover of the UE to the EPLMN of the neighbor BS (step 525).

If the EPLMN of the UE is not included in the available PLMN of the target cell (step 520), the Node B discards the handover to the UE (step 530).

6 is a block diagram of a base station according to an embodiment of the present invention.

Referring to FIG. 21, the base station includes a memory 610, a processor unit 620, an input / output control unit 640, a display unit 650, and an input device 660. Here, a plurality of memories 610 may exist. The components are as follows.

The memory 610 includes a program storage unit 611 for storing a program for controlling the operation of the base station and a data storage unit 612 for storing data generated during program execution.

The data storage unit 612 may store data necessary for the operations of the application program 613 and the PLMN management program 614. [

The program storage unit 611 includes an application program 613 and a PLMN management program 614. Here, the program included in the program storage unit 611 may be expressed as a set of instructions and an instruction set.

The application program 613 includes an application program operating in the base station. That is, application program 613 includes instructions of an application that is driven by processor 622. [

The PLMN management program 614 recognizes whether the reserved for operator use field of the PLMN included in the Served cell information IE is reserved or Notreserved when exchanging X2 SETUP REQUEST / RESPONSE and ENB CONFIGURATION UPDAT / ACKNOWLEDGE messages with the neighboring base station, It is stored in the data storage unit 612 whether it is reserved or not reserved for the PLMN. The PLMN management program 614 performs the same operation on the EPLMN for the corresponding PLMN.

Thereafter, upon receiving the Measurement Report from the UE, the PLMN management program 614 checks whether the PLMN and EPLMN of the UE included in the data storage unit 612 are reserved or NotReserved, If not, the handover of the terminal is performed.

Memory interface 621 controls access to memory 610 of components such as processor 622 or peripheral device interface 623.

The peripheral device interface 623 controls the connection of the processor 622 and the memory interface 621 to the input / output peripheral of the base station.

The processor 622 controls the base station to provide the corresponding service using at least one software program. At this time, the processor 622 executes at least one program stored in the memory 610 to provide a service corresponding to the program.

The input / output control unit 640 provides an interface between the input / output device such as the display unit 650 and the input device 660 and the peripheral device interface 623.

The display unit 650 displays status information, characters to be input, a moving picture, and a still picture. For example, the display unit 650 displays application program information driven by the processor 622.

The input device 660 provides the input data generated by the selection of the base station to the processor unit 620 through the input / output control unit 640. At this time, the input device 660 includes a keypad including at least one hardware button and a touch pad for sensing touch information. For example, the input device 660 provides touch information such as touch, touch movement, and touch release sensed through the touch pad to the processor 622 through the input / output control unit 640.

In addition, the base station includes a communication processing unit 690 that performs communication functions for voice communication and data communication.

7 is a detailed block diagram of a base station according to an embodiment of the present invention.

Referring to FIG. 7, the processor of the present invention includes an application program driver 710 and a PLMN management program driver 730.

The application program driving unit 730 executes the application program 613 stored in the program storage unit 611 via the memory interface 621 and provides a service on the operating system according to the application.

The PLMN management program drive unit 730 executes the PLMN management program 614 of the program storage unit 611 via the memory interface 621 and provides a service on the operating system according to the program.

In particular, the PLMN management program drive unit 730 provides the PLMN management program 614 with a communication function with other nodes via the peripheral device interface 623 and the communication processing unit 690.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. Therefore, the scope of the present invention should not be limited by the illustrated embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

Claims (18)

A method of a base station for preventing unnecessary handover in a mobile communication system,
Exchanging information on a PLMN of a neighboring BS and a UE,
Determining whether handover to the neighboring base station of the mobile station is possible based on information on the PLMN of the mobile station;
Stopping the handover of the MS to the neighbor BS when the handover is not possible;
And if the handover is possible, proceeding to handover to the neighboring base station of the terminal.
The method according to claim 1,
The information on the PLMN of the UE is
And whether the PLMN or EPLMN is reserved or not reserved for the neighboring base station.
3. The method of claim 2,
Wherein the step of determining whether handover to the neighboring base station is possible,
And determining whether the PLMN or EPLMN is reserved for the neighboring base station.
The method of claim 3,
If the handover is impossible,
And the PLMN or EPLMN is reserved for the neighboring base station.
The method of claim 3,
If the handover is possible,
And the PLMN or EPLMN of the UE is not reserved to the neighboring base station.
The method according to claim 1,
The process of exchanging information on the PLMN of the neighboring BS and the UE
And exchanging X2 SETUP REQUEST and X2 SETUP REQUEST RESPONSE messages with the neighbor BS.
The method according to claim 6,
The X2 SETUP REQUEST and X2 SETUP REQUEST RESPONSE messages
Wherein the Served Cell Information IE includes information on whether the PLMN or the EPLMN is reserved or not reserved for the neighboring base station.
The method according to claim 1,
The process of exchanging information on the PLMN of the neighboring BS and the UE
And exchanging an ENB CONFIGURATION UPDATE and an ENB CONFIGURATION UPDATE ACKNOWLEDGE message with the neighboring base station.
9. The method of claim 8,
The ENB CONFIGURATION UPDATE and ENB CONFIGURATION UPDATE ACKNOWLEDGE messages
Wherein the Served Cell Information IE includes information on whether the PLMN or the EPLMN is reserved or not reserved for the neighboring base station.
An apparatus for a base station for preventing unnecessary handover in a mobile communication system,
At least one processor,
A memory,
A communication processor for exchanging information on the PLMN of the neighboring BS and the MS,
At least one program stored in the memory and being driven by the one or more processors,
The program includes:
Determining whether handover to the neighboring base station of the terminal is possible based on information of the PLMN of the terminal, stopping the handover of the terminal to the neighboring base station when the handover is impossible, And proceeds to handover to the neighboring base station of the terminal if possible.
11. The method of claim 10,
The information on the PLMN of the UE is
And whether the PLMN or EPLMN is reserved or not reserved for the neighboring base station.
12. The method of claim 11,
The program includes:
When determining whether handover to the neighboring base station is possible,
And determining if the PLMN or EPLMN is reserved for the neighboring base station.
13. The method of claim 12,
If the handover is impossible,
And the PLMN or EPLMN is reserved to the neighboring base station.
13. The method of claim 12,
If the handover is possible,
And the PLMN or EPLMN of the UE is not reserved to the neighboring BS.
11. The method of claim 10,
The program includes:
When exchanging information on the PLMN of the neighboring BS and the MS,
And exchanging X2 SETUP REQUEST and X2 SETUP REQUEST RESPONSE messages with the neighboring base station.
16. The method of claim 15,
The X2 SETUP REQUEST and X2 SETUP REQUEST RESPONSE messages
Wherein the Served Cell Information IE includes information on whether the PLMN or EPLMN is reserved or not reserved for the neighboring base station.
11. The method of claim 10,
The program includes:
When exchanging information on the PLMN of the neighboring BS and the MS,
And exchanges an ENB CONFIGURATION UPDATE and an ENB CONFIGURATION UPDATE ACKNOWLEDGE message with the neighboring base station.
18. The method of claim 17,
The ENB CONFIGURATION UPDATE and ENB CONFIGURATION UPDATE ACKNOWLEDGE messages
Wherein the Served Cell Information IE includes information on whether the PLMN or EPLMN is reserved or not reserved for the neighboring base station.

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