KR101328169B1 - Method for paging in communication system - Google Patents

Abstract

When a femtocell base station located within an area of a macrocell base station provides a paging service to a terminal, it receives paging information from a macrocell base station having the same paging group identifier as the paging group identifier of the femtocell base station. Then, the terminal transmits the common paging area information including the paging information to the terminal, and when the paging message is received from the paging controller, transmits the paging message received from the paging controller based on the common paging area information to the terminal to provide the paging service to the terminal. .

Description

Method for providing paging service in communication system supporting femtocell {Method for paging in communication system}

The present invention relates to a paging service providing method in a broadband wireless communication system supporting a femtocell.

A femtocell provides a wireless service to a terminal in an area where a cell radius is about 30 meters. The femtocell base station is a small base station installed to support the femtocell in the macrocell and provides better signal quality than the macrocell base station in a dense area such as a home or office.

In the broadband wireless communication system, the terminal receives various services from the base station, and when the service is terminated, the terminal enters the idle mode from the service activation state. The terminal receives a paging service and a location-based service from the base station in the dormant mode.

When the terminal performs a procedure to enter the dormant mode, the base station supports a paging service or a location-based service to the terminal, the temporary identifier (TempID), the paging group identifier (PGID) of the base station, the paging cycle and paging offset Send information such as;

Therefore, the femtocell base station must support the paging service to the terminal in the same manner as the macrocell base station. In this case, a method of providing a paging service according to a method of allocating a paging group identifier to a terminal may be divided into various methods.

However, according to a method of supporting a paging service, in some methods, the UE needs to perform a location update procedure as the UE moves from a macrocell to a femtocell or a femtocell to a macrocell. At this time, there is a problem that the location update procedure occurs frequently, thereby increasing the signaling overhead. In addition, in some methods, signal interference between the macrocell base station and the femtocell base station increases in the macrocell.

Accordingly, the present invention provides a method for providing a paging service in which a signal interference due to paging message transmission does not occur while reducing a frequent location update procedure in a wireless communication system in which a macrocell and a femtocell coexist.

Method for providing a paging service to a terminal by a femtocell base station located within the area of the macrocell base station which is one feature of the present invention for achieving the technical problem of the present invention,

Receiving paging information from a macrocell base station having the same paging group identifier as the paging group identifier of the femtocell base station; Transmitting common paging area information including paging information to the terminal; Receiving a paging message from a paging controller; And transmitting the received paging message to the terminal based on the common paging area information.

In another aspect of the present invention, there is provided a method for receiving a paging service by a terminal in a communication system in which a femtocell base station and a macrocell base station coexist.

Transmitting a base station registration request message to the femtocell base station; Receiving common paging area information from the femtocell base station; And receiving a paging message from any one of the femtocell base station or the macrocell base station.

According to an embodiment of the present invention, since the femtocell base station has the same paging group identifier as the paging group identifier of the macrocell base station in a communication system where the macrocell and the femtocell coexist, the system overhead due to frequent location information update of the terminal is reduced. Can be.

In addition, since the macrocell base station and the femtocell base station transmit the paging message in the same resource region by transmitting information on the common paging area from the macrocell base station to the femtocell base station, signal interference between the macrocell base station and the femtocell base station can be prevented.

1 is a diagram illustrating a paging method when a macrocell base station and a femtocell base station belong to different paging groups in general.
2 is a diagram illustrating a paging method when a macrocell base station and a femtocell base station generally belong to the same paging group.
3 is a flowchart illustrating a paging procedure in a macrocell base station and a femtocell base station generally belonging to the same paging group.
4 is an exemplary diagram illustrating a method of allocating a common paging area according to an exemplary embodiment of the present invention.
5 is a flowchart illustrating a paging procedure using a common paging area 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. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters 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 otherwise stated.

In this specification, a terminal includes a mobile station (MS), a mobile terminal (MT), a subscriber station (SS), a portable subscriber station (PSS) An access terminal (AT), and the like, and may include all or some of functions of a mobile terminal, a subscriber station, a mobile subscriber station, a user equipment, and the like.

In this specification, a base station (BS) is an access point (AP), a radio access station (RAS), a node B, a base transceiver station (BTS) Mobile Multihop Relay) -BS, and may include all or some of the functions of an access point, a radio access station, a Node B, a base transceiver station, and an MMR-BS.

Hereinafter, a paging method in a broadband wireless communication system supporting a femtocell according to an embodiment of the present invention will be described with reference to the accompanying drawings. Before describing an embodiment of the present invention, a paging method in a general communication system environment will be described with reference to FIGS. 1 to 3.

1 is a diagram illustrating a paging method when a macrocell base station and a femtocell base station belong to different paging groups in general.

As shown in FIG. 1, when the macrocell base station and the femtocell base station belong to different paging groups, the terminal transmits a paging message only to either of the currently located femtocell base station or the macrocell base station. This reduces unnecessary paging message transfers.

However, when the terminal moves from the macro cell base station area to the femtocell base station area or the femtocell base station area to the macro cell base station area, the location information update procedure of the terminal should be performed. At this time, since the area radius of the femtocell base station is generally about 30 meters, the location information update procedure of the terminal frequently occurs. This increases the signaling overhead.

2 is a diagram illustrating a paging method when a macrocell base station and a femtocell base station generally belong to the same paging group. That is, FIG. 2 illustrates a case where the same paging identifier is allocated to the macro cell base station and the femtocell base station included in the area of the macro cell base station.

As the femtocell base station and the macrocell base station have the same paging group identifier as shown in FIG. 2, even if the terminal moves from cell to cell area of the femtocell base station or from the area of the macrocell base station to the area of the femtocell base station. There is no need to perform a location update procedure of the terminal.

3 is a flowchart illustrating a paging procedure in a macrocell base station and a femtocell base station generally belonging to the same paging group.

As shown in FIG. 3, the UE in the femtocell base station region uses the paging period and offset information allocated by the femtocell base station from the macrocell base station in the procedure for entering the dormant mode, and periodically transmits a paging message transmitted from the femtocell base station. Receive. In this case, all macrocell base stations and femtocell base stations belonging to the same paging group transmit the same paging message to the terminal based on the paging period and the offset, thereby increasing signal interference in the macrocell base station area.

Therefore, in the embodiment of the present invention will be described a paging method for reducing the frequent location information update procedure of the terminal while preventing signal interference due to the transmission of the paging message. To this end, in the embodiment of the present invention, it is assumed that the femtocell base station and the macrocell base station have the same paging group identifier.

4 is an exemplary diagram illustrating a method of allocating a common paging area according to an exemplary embodiment of the present invention.

As shown in FIG. 4, the common paging area information generated by the macrocell base station includes a paging group identifier allocated to the macrocell base station itself, a paging period, a paging offset, a frame offset indicating a frame in the paging offset, and a subframe within the frame. Offset, symbol offset indicating the start position of the common paging area within the subframe, and subchannel offset information. In addition, the number of symbols and the number of subchannels indicating the size of the common paging area are included.

Next, a method of providing a paging service using the common paging area information described with reference to FIG. 4 to a terminal to enter a dormant state will be described with reference to FIG. 5.

5 is a flowchart illustrating a paging procedure using a common paging area according to an embodiment of the present invention.

As shown in FIG. 5, the macrocell base station generates common paging area information (S100). The common paging area information includes paging group identifier, paging period, paging offset, frame offset, sub frame offset, symbol offset, and sub channel offset information. The common paging area information also includes the number of symbols and the number of subchannels.

The femtocell base station transmits to the macrocell base station a base station registration request message (Femtocell_Req) requesting the base station registration in order to locate the femtocell base station in the area of the macrocell base station (S110). At this time, the base station registration request message includes a femtocell base station ID and location information where the femtocell base station is installed.

Upon receiving the base station registration request message from the femtocell base station, the macrocell base station determines that the femtocell base station exists in its area based on the location information of the femtocell base station and registers the femtocell base station. Then, common paging area information and MCS information for the paging service is transmitted to the femtocell base station (S120).

If the terminal located in the femtocell base station area is to change the state to the dormant mode, the terminal transmits a deregistration request (Dreg_Req: Deregistration_Request) message to the femtocell base station (S130). Upon receiving the deregistration request message from the terminal, the femtocell base station transmits a deregistration command (Dreg_CMD) message to the terminal (S140). The deregistration command message includes a paging group identifier, a paging period, and paging offset information allocated to the femtocell base station.

After the femtocell base station transmits the deregistration command message to the terminal or according to a preset paging period, the femtocell base station and the macrocell base station receive paging messages from the paging controller, respectively (S150 and S155). Then, the femtocell base station and the macrocell base station modulate and code the paging message according to a predetermined MCS through steps S100 and S120, respectively.

In operation S160, the terminal receives the registration cancellation command message through the common paging area to the terminal in the dormant mode. At this time, when the femtocell base station transmits a paging message to the common paging area, the femtocell base station transmits a paging message after controlling power according to the distance to the macrocell base station. The method for controlling power is already known, and detailed description thereof will be omitted in the exemplary embodiment of the present invention. As described above, since the same paging message is modulated and coded according to the MCS and then transmitted to the terminal using the common paging area, multiple gains can be obtained in the macro cell base station area.

On the other hand, the terminal receiving the deregistration command message from the femtocell base station changes the state to the sleep mode operation, the paging message transmitted from the femtocell base station or the macrocell base station according to the paging cycle and paging offset information included in the deregistration command message Receive (S160). At this time, the terminal is located in the femtocell base station area, the subject of the base station for transmitting the paging message to the terminal depends on the location of the femtocell base station.

That is, when the femtocell base station is installed in close proximity to the macrocell base station, the femtocell base station does not transmit the paging message using the common paging area to the terminal, but transmits only paging message allocation information. The terminal receiving the paging message assignment information receives the paging message transmitted from the macro cell base station based on this.

The terminal located in the femtocell base station area receives the paging message transmitted to the common paging area among the signals transmitted from the macrocell base station using the paging message allocation information received from the femtocell base station. Here, the paging message allocation information relates to the common area allocation information to which the paging message is transmitted by the macrocell base station.

However, if the femtocell base station is not installed in close proximity to the macrocell base station, the terminal receives a paging message transmitted by the femtocell base station. At this time, the distance between the femtocell base station and the macrocell base station for receiving the paging message transmitted by the macrocell base station to the terminal located in the femtocell base station area may be arbitrarily set.

Meanwhile, when the macro cell base station wants to change the common paging area, the macro cell base station should transmit the changed common paging area information to all femtocell base stations in the macro cell base station area. The macrocell base station and the femtocell base station may use the remaining resources except for the resources used for transmitting the paging message in the common paging area to transmit other data.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, It belongs to the scope of right.

Claims (10)

A method for providing a paging service to a terminal by a femtocell base station located within an area of a macrocell base station,
Receiving paging information from a macrocell base station having the same paging group identifier as the paging group identifier of the femtocell base station;
Transmitting common paging area information including paging information to the terminal;
Receiving a paging message from a paging controller; And
Transmitting the received paging message to the terminal based on the common paging area information.
Paging service providing method comprising a. The method of claim 1,
The transmitting of the common paging area information may include:
Receiving a base station registration request message from the terminal; And
Transmitting the common paging area information
Including;
The common paging area information further includes a modulation and coding scheme (MCS) information. 3. The method of claim 2,
The step of transmitting the paging message,
Modulating and coding the paging message based on the MCS information
Paging service providing method comprising a. The method of claim 1,
After receiving the paging message,
If the femtocell base station is located adjacent to the macrocell base station, transmitting paging message allocation information to the terminal;
Paging service providing method further comprising. 5. The method of claim 4,
And the paging message assignment information includes the common paging area information. The method of claim 5,
The common paging area information may be set in the macrocell base station to determine at least one of paging group identifier, paging period, paging offset, frame offset, subframe offset, symbol offset, subchannel offset, symbol number, and subchannel number. Paging service providing method comprising. In a communication system in which a femtocell base station and a macrocell base station coexist, the terminal receives a paging service,
Transmitting a base station registration request message to the femtocell base station;
Receiving common paging area information from the femtocell base station; And
Receiving a paging message from any one of the femtocell base station or the macrocell base station
Paging service providing method comprising a. The method of claim 7, wherein
After receiving the common paging area information,
Receiving paging message allocation information from the femtocell base station; And
Receiving the paging message from the macrocell base station based on the received paging message allocation information
Paging service providing method further comprising. The method of claim 7, wherein
The common paging area information includes MCS information.
And the paging message is modulated and coded based on the MCS information. The method of claim 7, wherein
Receiving the common paging area information,
Receiving a deregistration command message from the femtocell base station in response to the registration request message;
Including;
The deregistration command message includes a paging group identifier, paging period, and paging offset information allocated to the femtocell base station.

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