KR20100048881A - Termianl, method for handover of thereof and supporting method for handover of base station - Google Patents

Abstract

PURPOSE: A terminal, a method for handover thereof, and a supporting method for the handover of a base station are provided to efficiently generate and manage a neighboring base station list including femto cell information in order for a terminal to perform a handover process in a condition in which a plurality of femto cells and macro cells are superimposed. CONSTITUTION: A macro base station(100) manages a macro cell(10). The macro cell includes a plurality of femto cells(21,22,23) managed by the plurality of femto base stations(210,220,230). The macro cell represents a cell that is larger than the femto cell. The femto base stations represent very small base stations for providing a wireless communication service to small areas and manage the femto cell. For example, they are installed in a blanket area where propagation of other cells is degraded such as a house or a building to acquire a high quality mobile communication service. A terminal(300) represents the end terminal of a radio channel and accesses the femto base stations or the macro base station to transmit/receive data. The terminal performs a scan process based on the neighboring base station list broadcast by the macro base station. The terminal acquires measurement information on the neighboring macro base stations through the scan process. The measurement information includes information that can influence the handover such as RSSSI(Received Signal Strength Indicator), CNR(Carrier to Noise Ratio), and SINR(Signal to Interference Noise Ratio).

Description

Terminal, handover method of terminal and handover support method of base station {TERMIANL, METHOD FOR HANDOVER OF THEREOF AND SUPPORTING METHOD FOR HANDOVER OF BASE STATION}

The present invention relates to a terminal, a handover method of a terminal, and a handover support method of a base station.

When the terminal moves from a cell managed by one base station to a cell managed by another base station, the terminal performs a handover procedure. At this time, the base station originally connected to the terminal broadcasts a message including information on the neighbor base station to support the handover of the terminal. The terminal scans based on the information on the neighbor base station and performs handover.

On the other hand, a femto cell (femto cell) refers to the area where a wireless communication service is provided for an area within a radius of 30m, for example. A femto base station managing a femto cell is installed in an office or home. Many femto cells may be superimposed in a macro cell managing a cell of an area larger than a femto cell.

An object of the present invention is to efficiently generate and manage a neighbor base station list including information on a femtocell so that a terminal can handover in an environment where a plurality of femtocells and macrocells overlap.

A handover method according to an embodiment of the present invention is a handover method of a terminal in a macro cell including a plurality of femto cells, and includes information on a femto base station managing a femto cell around the terminal among the plurality of femto cells. Scanning, and reporting information on the femto base station to the macro base station managing the macro cell.

And receiving a neighbor base station list from the macro base station, wherein the neighbor base station list may include information of a femto base station accessible by the terminal among femto base stations managing a femto cell around the terminal.

The plurality of femto cells may be divided into a plurality of femto cell groups, and the information of the femto base station may include information of a femto cell group including a femto base station accessible by the terminal.

The neighbor base station list may further include location information of the femto base station.

The method may further include requesting a scan condition from the macro base station, and receiving the scan condition from the macro base station.

The method may further include receiving a reporting condition of the information on the femto base station from the macro base station.

The plurality of femto cells are divided into a plurality of femto cell groups, and the handover method includes an identifier indicating a femto cell group to which the terminal belongs among the plurality of reporting conditions broadcast from the macro base station to the femto base station. The method may further include extracting a reporting condition of the information about the information.

The method may further include extracting the femto cell information, and handing over to the femto base station.

The method may further include reporting location information of the terminal.

In a handover support method according to another embodiment of the present invention, in a handover support method of a macro base station managing a macro cell including a plurality of femto cells, the method comprising: receiving information on a femto base station obtained by scanning by a terminal; And generating a neighbor base station list including information of the femto base station accessible by the terminal based on the information on the femto base station, and transmitting the neighbor base station list to the terminal.

The method may further include receiving location information of the femto base station from the femto base station, and the neighbor base station list may be generated based on the location information of the femto base station.

The method may include receiving a scan condition from the terminal, and specifying a scan condition to the terminal.

The method may further include designating a reporting condition to the terminal.

The method may further include reporting location information of the terminal, and the neighbor base station list may be generated based on location information of the terminal.

A terminal according to another embodiment of the present invention includes a scan unit for scanning information on a femto base station managing a femto cell, and a transmission unit for reporting the information on the femto base station to a macro base station managing a macro cell.

The apparatus may further include a receiver configured to receive a neighbor base station list from the macro base station.

The neighbor base station list may include information of a femto base station accessible by the terminal among femto base stations managing the femto cell around the terminal.

The terminal may further include an extraction unit for extracting information on the femtocell required by the terminal based on the neighbor base station list.

The transmitter may request a scan condition from the macro base station, and the receiver may receive the scan condition from the macro base station.

The receiver may receive a condition for reporting the information on the femto base station to the macro base station from the macro base station.

According to the present invention, a neighbor base station list including information on a femtocell can be efficiently generated and managed so that a terminal can handover in an environment where a plurality of femtocells and a macrocell overlap.

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 otherwise stated.

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 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) includes an access point (AP), a radio access station (RAS), a node B (Node B), an advanced node B (evolved NodeB, eNodeB), transmission and reception It may also refer to a base transceiver station (BTS), a mobile multihop relay (MMR) BS, or the like, and may include all or a portion of an access point, a wireless access station, a node B, an eNodeB, a transmission / reception base station, an MMR ?? BS, or the like. It may also include functionality.

Now, a terminal, a handover method of a terminal, and a handover support method of a base station according to an embodiment of the present invention will be described in detail with reference to the drawings.

1 is a schematic diagram of a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 1, a wireless communication system according to an exemplary embodiment of the present invention includes a macro base station 100, a plurality of femto base stations 210, 220, and 230, and a terminal 300. It includes.

The macro base station 100 manages a macro cell 10. The macro cell 10 includes a plurality of femto cells 21, 22, and 23 managed by the plurality of femto base stations 210, 220, and 230, respectively. Macro cell 10 refers to a cell of a larger area than femto cell 20 and is not limited to the dictionary definition of the term macro.

The femto base station 210, 220, 230 refers to a very small base station that provides a wireless communication service for a narrow range (for example, 30m range) area, and manages the femto cell 20, for example, It is installed in a shaded area where radio waves of other cells are degraded, such as inside a building, to secure the quality of mobile communication services. Here, femto base stations 210, 220, 230 and femto cells 21, 22, 23 are not limited to the dictionary definition of femto (femto) of the small base station and the small cell having a name of a larger unit or smaller unit It is a term including the range.

The terminal 300 connects to the femto base station 210, 220, 230 or the macro base station 100 as an end point of the wireless channel and transmits and receives data.

A handover method according to an embodiment of the present invention will now be described in detail with reference to FIG. 2.

2 is a flowchart illustrating a handover method in order according to an embodiment of the present invention.

Referring to FIG. 2, a new terminal 300 enters the macro cell 10 in a state in which there is no terminal utilizing services for the femto cells 21, 22, and 23 in the macro cell 10 (S211). The macro base station 100 broadcasts the neighbor base station list to the terminal 300 (S212).

Subsequently, the terminal 300 requests a scan condition from the macro base station 100 (S213). Then, the macro base station 100 designates the scan condition to the terminal 300 requesting the scan condition (S214). In this case, the scan condition is a time and period for performing a scan, and the scan condition request step S213 and the scan condition request designation step S214 may be omitted.

The terminal 300 scans based on the neighbor base station list broadcasted by the macro base station 100 (S215). The terminal 300 obtains measurement information about neighboring macro base stations through a scan process (S215). The measurement information may affect handover such as received signal strength indicator (RSSI), carrier to noise ratio (CINR) and signal to interference noise ratio (SINR). Include information that can be On the other hand, when the femto base station 200 operates using a different frequency than the macro base station 100, the macro base station 100 may specify that the terminal 300 is divided into several groups to be periodically scanned at a predetermined time.

Subsequently, the macro base station 100 specifies a condition for reporting measurement information to the terminal 300 (S216). The macro base station 100 may inform such a condition by unicast at the request of each terminal 300 or broadcast all the terminals.

The terminal 300 reports the measurement result obtained through the scanning step (S215) (S217). In this case, the terminal 300 may report the measurement result according to the reporting condition received from the macro base station 100. When the measurement result is reported according to the reporting condition as described above, even if the number of the terminal 300 is large, the radio resource required for the report can be adjusted. Meanwhile, the terminal 300 may obtain the location information of the terminal 300 by using a location information acquisition device such as a global positioning system (GPS) and report it to the macro base station 100.

In addition, the surrounding femto base station 200 transmits measurement information such as signal quality, for example, RSSI, CINR, and SINR, for the neighboring macro cell 10 to the macro base station 100 through a wired network (S218). In this case, the femto base station 200 may transmit not only the measured information but also the location information acquired through the location information acquisition device such as GPS.

The macro base station 100 uses the measurement information received from the terminal 300 and the measurement information and the location information received from the femto base station 200, and the relative position with the neighboring macro base station and the femto base station 200 of the terminal 100. Estimates and selects a femto cell group available at the estimated location (S219). This is included in the neighbor base station list to generate an updated neighbor base station list. A femto cell group is divided into a plurality of groups of femto cells (21, 22, 23).

Thereafter, the macro base station 100 notifies or broadcasts the terminal 100 requesting the updated neighbor base station list by unicast (S220). The macro base station 100 may transmit only some of the femto cells 21, 22, and 23 belonging to the femto cell group to the terminal 100 in order to save resources and shorten the scan time of the terminal 300. The unselected femto cell may be transmitted from the macro base station 100 when requested or required by the terminal 300.

The terminal 300 extracts information on the femtocells 21, 22, and 23 required by the terminal based on the updated neighbor base station list received from the macro base station 100 (S221). In this case, the terminal 300 may perform the extraction step S221 using the femto cell group identifier indicating the femto cell group.

Then, based on the extracted femto cell (21, 22, 23) information, handover to the target femto base station 200 (S222).

On the other hand, the terminal 300 repeats the steps (S212 to S221) again.

When there is no terminal utilizing services for the femtocells 21, 22, and 23 and the new terminal 300 enters the macro cell 10, the neighboring base station list broadcasted by the macro base station 100 is a neighboring macro. Although only a list of cells 10 is included, the neighbor base station list broadcasted by the macro base station 100 after the terminal 300 has handed over to any femto cell 21, 22, 23 is a neighboring macro. A list for cell 10 and femto cells 21, 22, 23.

At this time, the terminal 300 scans using the extracted information on the femto cells 21, 22, and 23, and acquires specific information on neighboring macro base stations and femto base stations through the scanning step.

In addition, when the terminal 300 receives the measurement information reporting condition by broadcasting, the terminal 300 which has been previously allocated the femto cell group identifier may extract the measurement result reporting condition using the femto cell group identifier.

As described above, the terminal 300 reports the scanned information to the macro base station 100, and the macro base station 100 updates the neighbor base station list based on the neighbor base station list in an environment where a plurality of femto cells and macro cells overlap. It can be created and managed efficiently.

A terminal according to an embodiment of the present invention will now be described in detail with reference to FIG. 3.

3 is a block diagram schematically illustrating a terminal according to an embodiment of the present invention.

Referring to FIG. 3, the terminal 300 includes a receiver 310, a scan unit 320, a transmitter 330, and an extractor 340.

The receiver 310 receives a neighbor base station list, a scan condition, a measurement information report condition, and an updated neighbor base station list from the macro base station 100, and a signal required for a handover procedure from the macro base station 100 or the femto base station 200. Receive Here, the neighbor base station list includes information on the femto cell group available to the terminal 300.

The scan unit 320 acquires measurement information including RSSI, CINR, SINR, etc. of neighboring macro base stations by performing a scan according to a scan condition based on the neighbor base station list received by the receiver 310.

The transmitter 330 requests the scan conditions from the macro base station 100 and reports the measurement conditions acquired by the scan unit 320 to the macro base station 100 according to the measurement information reporting condition received by the receiver 310. .

The extractor 340 extracts information on the femtocell required by the terminal 300 based on the updated neighbor base station list received by the receiver 310.

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.

1 is a schematic diagram of a wireless communication system according to an embodiment of the present invention.

2 is a flowchart illustrating a handover method in order according to an embodiment of the present invention.

3 is a block diagram schematically illustrating a terminal according to an embodiment of the present invention.

Claims (20)

A handover method of a terminal in a macro cell including a plurality of femto cells, Scanning information on a femto base station managing a femto cell around the terminal among the plurality of femto cells, and Reporting the information on the femto base station to the macro base station managing the macro cell; Handover method comprising a. In claim 1, Receiving a neighbor base station list from the macro base station, The neighbor base station list is a handover method including the information of the femto base station accessible to the terminal among the femto base station to manage the femto cell around the terminal. In claim 2, The plurality of femto cells are divided into a plurality of femto cell groups, The information of the femto base station includes the information of the femto cell group including a femto base station accessible to the terminal. In claim 2, The neighbor base station list further comprises location information of the femto base station. In claim 1, Requesting a scan condition from the macro base station, and Receiving the scan condition from the macro base station. In claim 1, And receiving a reporting condition of the information on the femto base station from the macro base station. In claim 6, The plurality of femto cells are divided into a plurality of femto cell groups, The handover method may further include extracting a reporting condition of the information on the femto base station from the plurality of reporting conditions broadcast from the macro base station by using an identifier indicating the femto cell group to which the terminal belongs. Over way. In claim 1, Extracting the femto cell information, and Handing over to the femto base station Handover method further comprising. In claim 1, And reporting the location information of the terminal. In the handover support method of a macro base station managing a macro cell including a plurality of femto cells, Receiving information on the femto base station obtained by scanning by the terminal; Generating a neighbor base station list including information of a femto base station accessible by the terminal based on the information on the femto base station; Transmitting the neighbor base station list to the terminal; Handover support method comprising a. In claim 10, Receiving location information of the femto base station from the femto base station; And the neighbor base station list is generated based on the location information of the femto base station. In claim 10, Receiving a request for a scan condition from the terminal, and Designating a scan condition to the terminal Handover support method comprising a. In claim 10, And specifying a reporting condition to the terminal. In claim 10, Reporting the location information of the terminal; The neighbor base station list is generated based on the location information of the terminal handover support method. A scan unit for scanning information on the femto base station managing the femto cell, and And a transmitter for reporting the information on the femto base station to the macro base station managing the macro cell. 16. The method of claim 15, The terminal further comprises a receiving unit for receiving the neighbor base station list from the macro base station. The method of claim 16, The neighbor base station list is a terminal including information of the femto base station accessible to the terminal among the femto base station to manage the femto cell around the terminal. The method of claim 16, The terminal further comprises an extraction unit for extracting information on the femto cell required by the terminal on the basis of the neighbor base station list. The method of claim 16, The transmitter requests the scan condition from the macro base station, and the receiver receives the scan condition from the macro base station. The method of claim 16, The receiving unit receives a condition for reporting the information on the femto base station to the macro base station from the macro base station.

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