KR101387481B1 - Method of performing handover in wireless communication system using multi-carrier - Google Patents

Abstract

The present invention relates to a method for performing handover in a wireless communication system using multiple carriers. The method for performing handover according to the present invention is a method for performing handover of a terminal performing an operation according to a band AMC mode in a wireless communication system using a multicarrier, the method comprising: specifying a particular number among a plurality of subbands constituting an entire band; Transmitting or receiving uplink or downlink data to and from a serving base station through a subband, and performing handover according to channel quality for each band and performing any one of a plurality of subbands constituting the entire band. And establishing a connection with the target base station through the sub band.

Multicarrier, Handover, Macro Diversity, CINR, Band AMC Mode

Description

Method of performing handover in wireless communication system using multi-carrier}

1 is a flowchart illustrating a macro diversity handover procedure in a broadband wireless access system, which is a kind of a wireless communication system.

2 illustrates a band configuration for a band AMC mode used in a broadband wireless access system.

3 is a flowchart illustrating a method for performing macro diversity handover according to an embodiment of the present invention.

4 is a flowchart illustrating a method for performing macro diversity handover according to another embodiment of the present invention.

The present invention relates to a wireless communication system using a multi-carrier, and more particularly, to a method for performing handover in a wireless communication system using a multi-carrier.

FIG. 1 is a flowchart illustrating a macro diversity handover (MDHO) procedure in a broadband wireless access system, which is a kind of a wireless communication system.

Referring to FIG. 1, a mobile station (MS) obtains information on a neighbor base station (BS # 2, hereinafter, 'target base station') from a base station (BS # 1, hereinafter, a 'serving base station') to which a connection is currently established. Receive MOB_NBR-ADV message included. When the terminal determines that the target base station can provide a higher signal quality or quality of service (QoS) than the serving base station based on the information on the target base station, by sending a MOB_MSHO-REQ message to the serving base station Request macrodiversity handover to the target base station. The terminal selects an anchor base station among base stations belonging to the diversity set and informs the serving base station through the MOB_MSHO-REQ message. In the example of FIG. 1, it is assumed that the serving base station is selected as the anchor base station.

The serving base station makes a handover decision when the terminal requests a handover, and transmits a MOB_MSHO-RSP message to the terminal in response to the MOB_MSHO-REQ message to allow the handover to be performed. The MOB_MSHO-RSP message includes information indicating that the target base station is included in a diversity set. The base stations included in the handover set, that is, the serving base station and the target base station share all information for connection with the terminal.

The terminal informs that the handover procedure is initiated by sending a MOB_HO-IND message to the serving base station. After performing the handover, the terminal may obtain diversity gain by combining and receiving the same data, for example, a MAC PDU (Medium Access Control Protocol Data Unit) from the serving base station and the target base station.

When the terminal wants to change the anchor base station to the target base station, the terminal sets a 'preferred anchor BS' as the target base station BS # 2 through a MOB_MSHO-REQ message and transmits it to the serving base station. The serving base station displays the updated anchor base station in the MOB_BSHO-RSP message and transmits it to the terminal. The terminal may transmit that the updated anchor base station has been accepted through the MOB_HO-IND message.

2 illustrates a band configuration for a band AMC mode used in a broadband wireless access system. The basic unit constituting the AMC subchannel is a bit composed of nine adjacent subcarriers in the same symbol. One bin consists of eight data subcarriers and one pilot subcarrier. There are four bins in one band, and the AMC subchannel consists of six adjacent bins in the same band. The broadband wireless access system has a subchannel structure in the form of a 2 × 3 matrix. In the case of the band AMC mode, there is an advantage that a different MCS level may be applied per band. Since the terminal needs to report channel quality for each band, it is difficult to use the band AMC mode for a terminal moving at high speed.

In a broadband wireless access system, a terminal using a band AMC mode transmits channel quality information for five bands having the best channel quality when reporting channel quality to a base station. The base station allocates the AMC subchannel in the band with the best channel quality. After the terminal is allocated the AMC subchannel from the base station reports the difference value for the first reported channel quality value. Band AMC mode may be initiated by the base station as well as the terminal. The base station sends an REP-REQ message to the terminal to instruct the start of the band AMC mode, the terminal may respond with a REP-RSP message and then start the band AMC mode operation.

In the broadband wireless access system according to the prior art, the terminal performs handover over the entire frequency band regardless of the subcarrier allocation scheme. However, as described above, the terminal operating in the band AMC mode does not use the entire band but communicates with the base station by using a specific subband among the plurality of subbands in which the entire band is divided. Performing a handover may cause a variety of problems such as poor data reception efficiency.

The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is that the terminal performing the operation according to the band AMC mode in the broadband wireless access system can efficiently perform the handover To provide a way.

Another object of the present invention is to provide a method for a terminal performing an operation according to a band AMC mode in a broadband wireless access system to perform macro diversity handover.

In order to solve the above technical problem, the present invention, if the terminal is operating in a band AMC mode in the serving base station (serving base station) before performing the handover target base station (target base station) even during the handover or after performing the handover A method of enabling operation according to the over-band AMC mode is disclosed.

According to an aspect of the present invention, in a broadband wireless access system, a terminal or terminal that performs communication with a serving base station through a specific band is divided into a plurality of sub-bands, and the channel or signal quality is increased among the sub-bands. It is to select a good band to perform a handover to the target base station.

According to another aspect of the present invention, a terminal operating according to a band AMC mode in a broadband wireless access system performs band-by-band macro diversity handover to receive the same data or different types of data from a serving base station and a target base station, Diversity gain can be obtained by combining or concatenating the received data.

In one aspect of the present invention, a method for performing macro diversity handover according to the present invention may include a method for performing macro diversity handover (MDHO) in a wireless communication system using a multi-carrier. The anchor base station and the channel quality information for at least one sub-band from among a plurality of sub-bands constituting the entire band for each of the anchor base station and the neighbor base station belonging to the diversity set (diversity set) Transmitting to at least one of the neighbor base stations, and receiving allocation information of each sub band selected from the at least one sub band for each of the anchor base station and the neighbor base station from any one of the anchor base station and the neighbor base station. And from each anchor base station and a neighboring base station. When receiving a downlink data via a respective sub-band allocated and a predetermined condition is satisfied characterized by configured by comprising the step of terminating the connection with the anchor base station.

In another aspect of the present invention, the method for performing handover according to the present invention is a method for performing handover of a terminal performing an operation according to a band AMC mode in a wireless communication system using multiple carriers. Transmitting or receiving uplink or downlink data between a serving base station and a serving base station through a specific subband among a plurality of subbands, and performing a handover according to channel quality for each band, And establishing a connection with the target base station through any one of the subbands.

The construction, operation, and other features of the present invention will be readily understood by embodiments of the present invention described below with reference to the accompanying drawings. The embodiments described below are embodiments in which the technical features of the present invention are applied to a broadband wireless access system, and the matters not described in this document are "IEEE Standard for Local and" which is a technical standard for a broadband wireless access system. metropolitan area networks, Part 16: Air Interface for Fixed and Mobile Broadband Wireless Access Systems, Amendment 2: Physical and Medium Access Control Layers for Combined Fixed and Mobile Operation in Licensed Bands, 28 February 2006.

3 is a flowchart illustrating a method for performing macro diversity handover in a broadband wireless access system according to an embodiment of the present invention. 3 illustrates an example in which a UE initiates a handover procedure.

Referring to FIG. 3, a terminal performing an operation according to a band AMC mode receives a MOB_NBR-ADV message including information on neighboring base stations from a serving base station BS # 1 [S31]. . The terminal scans the neighbor base stations based on the information about the neighbor base stations included in the MOB_NBR-ADV message [S32]. The terminal may determine to include a specific base station BS # 2 in a diversity set among the neighboring base stations according to a scan result of the neighboring base stations. For example, when the carrier to interference and noise ratio (CINR) of the specific neighboring base station BS # 2 is equal to or greater than a preset threshold, the neighboring base station may be included in the diversity set. In this case, the terminal performs scanning for each band in the scanning process for the neighbor base stations. That is, since the terminal operates according to the band AMC mode, channel quality, for example, CINR, is measured by performing band-by-band scanning on each neighboring base station instead of the entire band. In addition, the terminal determines whether to include in the diversity set based on the channel-specific channel quality measured for each neighboring base station. For example, when the upper five CINRs among the band-specific CINRs for each neighboring base station are greater than or equal to a preset threshold, the neighboring base station may be included in the diversity set. These criteria can be changed in various forms. As another example of updating base stations belonging to the diversity set, a method of using MBHO_Add_Threshold and MBHO_Delete_Threshold may be considered as described through Table 1 below.

Name Type Length Value PHY scope ...... HO type support 50 One Bit 0: HO
Bit 1: MDHO
Bit 2: FBSS HO
Bit 3: MBHO
Bit 4-7: Reserved MBHO_Add_Threshold Threshold used by the MS to add neighbor BS to the multiband diversity set. When the MS should send MOB_MSHO-REQ to request adding this neighbor BS to the diversity set. This threshold is used for the MS that is perform MBHO. MBHO_Delete_Threshold Threshold used by the MS to delete neighbor BS to the multiband diversity set. When the MS should send MOB_MSHO-REQ to request adding this neighbor BS to the diversity set. This threshold is used for the MS that is perform MBHO. ......

The terminal transmits a MOB_MSHO-REQ message to the serving base station in order to add the neighbor base station to the diversity set and to perform macro diversity handover (MDHO, hereinafter 'handover') [S33]. The MOB_MSHO-REQ message includes a scan result for neighboring base stations and an indicator indicating that the serving base station is selected as an anchor base station. The MOB_MSHO-REQ message may indicate that the scan result reporting criterion is CINR for each band. Table 2 shows an example of a format of the MOB_MSHO-REQ message.

Syntax Size Notes MOB_MSHO-REQ Message_format () { - Management Message Type = 57 8bits - Report metric 8bits Bitmap indicating presence of metric in message
Bit # 0: BS CINR mean
Bit # 1: BS RSSI mean
Bit # 2: Relative delay
Bit # 3: BS RTD
Bit # 4: BS CINR per band
Bit # 5-7: Reserved: shall be set to zero N_New_BS_Index 8bits Number of new recommended BSs which are included in MOB_NBR-ADV message ...... For (j = 0; j <N_New_BS_Index; j ++) { ...... If (Report metric [Bit # 4] == 1) NBand Number of band For (j = 0; j <NBand; j ++) { BS CINR per band The BS CINR per band parameter indicates the CINR in db measured at the MS on the downlink signal of a band of particular BS Band bitmap } Band AMC report 32 First 12 bits for indicating band bitmap and 20bits for CINR per best 5 bands Arrival time difference indication If (arrival time difference indication) == 1 { Arrival time difference (t) Relative difference in arrival time between the neighbor BS and the anchor BS } For (j = 0; J <N_New_BS_Full; j ++) ...... If (Report metric [Bit # 4] == 1) NBand For (j = 0; j <NBand; j ++) { BS CINR per band The BS CINR per band parameter indicates the CINR in db measured at the MS on the downlink signal of a band of particular BS Band bitmap } Band AMC report 32 First 12 bits for indicating band bitmap and 20bits for CINR per best 5 bands Arrival time difference indication If (arrival time difference indication) == 1 { Arrival time difference (t) Relative difference in arrival time between the neighbor BS and the anchor BS } ...... For (j = 0; j <N_current_BSs; j ++) { Temp BS ID Diversity Set member ID assigned to this BS. When the MS has an empty diversity set or FBSS / MDHO / MBHO is not supported, Temp BSID shall be set to 0 ...... If (Report metric [Bit # 4] == 1) NBand For (j = 0; j <NBand; j ++) { BS CINR per band The BS CINR per band parameter indicates the CINR in db measured at the MS on the downlink signal of a band of particular BS Band bitmap } Band AMC report 32 First 12 bits for indicating band bitmap and 20bits for CINR per best 5 bands ......

Upon receiving the MOB_MSHO-REQ message, the serving base station determines whether to allow a handover request [S34], when the serving base station decides to allow the handover request, the serving base station is assigned to the indicator and diversity set that allows the handover request. A MOB_BSHO-RSP message including information associated with base stations BS # 1 and BS # 2 belongs to the UE [S35]. The MOB_BSHO-RSP message includes indication information indicating that the serving base station is to be an anchor base station. Hereinafter, the serving base station will be referred to as an 'anchor base station'. Table 3 shows an example of a format of the MOB_BSHO-RSP message.

Syntax Size Notes MOB_BSHO-RSP Message_format () { - Management Message Type = 58 8bits - Mode 3bits 0b000: HO request
0b001: MDHO / FBSS / MBHO request: Anchor BS update with CID update
0b010: MDHO / FBSS / MBHO request: Anchor BS update without CID update
0b011: MDHO / FBSS / MBHO request: Diversity Set update with CID update
0b100: MDHO / FBSS / MBHO request: Diversity Set update without CID update
0b110: MDHO / FBSS / MBHO request: Diversity Set update with CID update and CQICH allocation for newly added BS
0b111: MS handover request not recommended (BS in list unavailable)
......

When the anchor base station transmits the MOB_BSHO-RSP message to the terminal, the terminal, the anchor base station BS # 1 and the neighboring base station BS # 2 maintain a connection state while maintaining a macro diversity hand. Ready to perform the over. That is, the anchor base station and the neighbor base station belonging to the diversity set share context information related to the terminal, and the terminal maintains a connection state with the two base stations. The context related to the terminal includes registration information, authentication information, and data being transmitted / received. Accordingly, the terminal may communicate with base stations in the diversity set for unicast messages and traffic data of downlink (DL) and uplink (UL).

There may be two ways for the UE to acquire a downlink broadcast message such as DL-MAP, UL-MAP, FCH, etc., which are downlink control information. The first case is that DL-MAP and UL-MAP of an anchor base station have both burst allocation information for other neighboring base stations within a diversity set, and the terminal includes downlink control information and downlink for the neighboring base station. A broadcast message may be obtained from the anchor base station. Second, the terminal receives the corresponding downlink control information and broadcast message from each base station in the diversity set.

The anchor base station allocates the best state band to the terminal through DL-MAP based on the channel quality (ex. CINR) measurement result for each band [S36]. The neighboring base station also selects the band having the best channel state based on the CINR result for each band reported by the terminal and allocates the band to the terminal through DL-MAP [S37]. In other words, the UE measures the CINR for each band for the anchor base station and the neighbor base station, and periodically or aperiodically transmits the CINR measurement result for the top five bands that are best according to the measurement result to the anchor base station and the neighbor base station. You can report it. Each of the anchor base station and the neighbor base station may allocate a band corresponding to the best value among the CINR values received from the terminal to the terminal.

In this case, in order to avoid the case where the band selected by the anchor base station and the band selected by the neighboring base station are the same, when the terminal has the highest quality band to report to the neighboring base station and the highest quality band to report to the neighboring base station, The neighbor base station may report CINRs for the remaining bands except for the matching band.

The terminal transmits a MOB_HO-IND message indicating the start of handover to the anchor base station [S38]. Table 4 shows an example of the format of the MOB_HO-IND message.

Syntax Size Notes MOB_HO-IND Message_format () { - Management Message Type = 59 8bits Reserved Mode 2bits 0b00: HO
0b01: MDHO / FBSS / MBHO: Anchor BS update
0b10: MDHO / FBSS / MBHO: Diversity Set update
0b11: Reserved ......

The anchor base station delivers the MOB_HO-IND message received from the terminal to an upper entity [S39]. The higher entity converts higher layer data to be transmitted to the terminal into lower layer data and transmits the higher layer data to base stations belonging to the diversity set, that is, the anchor base station and the neighboring base station [S40, S41]. That is, the higher entity is an entity that performs a function of scheduling user data transmitted from an upper layer of the network or another upper entity and transmitting the same to the base stations included in the diversity set. The upper layer or upper layer of the anchor base station It is an object. In the example of FIG. 3, it is represented by DP (Data Path) # 1. The neighbor base station has been indicated to have DP # 2 as a higher layer or higher entity.

The anchor base station and the neighbor base station transmit user data, that is, downlink (DL) data, received from the DP # 1 to the terminal through the band allocated to the terminal, respectively [S42, S43]. The downlink data may be transmitted in units of Medium Access Control Ptorocol Data Unit (MAC PDU). MAC PDUs transmitted from the anchor base station and the neighbor base station to the terminal may be the same or different. Type classification of a MAC PDU may be performed by the DP # 1.

The terminal acquires time-frequency region allocation information for transmitting downlink data through DL-MAP on a DL frame transmitted from the anchor base station, and selects the corresponding time-frequency region. Receives downlink data through [S42].

The method for receiving downlink data from the neighbor base station by the terminal may consider two methods. First, the terminal is transmitted to the terminal through the neighbor base station through the DL MAP on the downlink frame transmitted from the anchor base station (eg, 'DL Band AMC burst allocation in other BS IE' of the DL MAP) Acquisition of downlink data and allocation information of a time-frequency domain allocated for transmission of the downlink data, thereby receiving downlink data through the corresponding time-frequency domain on the downlink frame transmitted from the neighboring base station. [S42]. In this case, the terminal may not refer to the DL-MAP of the downlink frame transmitted from the neighbor base station. Second, the terminal receives the downlink frame transmitted from the neighboring base station, obtains time-frequency domain allocation information in which downlink data is transmitted through DL MAP of the received downlink frame, and through the corresponding time-frequency domain A method of receiving downlink data [S43].

Table 5 and Table 6 show the allocation information of the time-frequency domain allocated for the transmission of downlink data by the neighboring base station to the DL MAP on the downlink frame transmitted by the terminal from the anchor base station according to the first method, respectively. An extended DIUC structure for inclusion and a format structure of 'DL Band AMC burst allocation in other BS IE' are shown.

Extended DIUC
(hexadecimal) Usage 00 Channel_Measurement_IE ...... ...... 0C DL BandAMC Burst Allocation in Other BS OD-0E Reserved

Syntax Size Notes DL BandAMC Burst Allocation in other BS IE () { - Extended DIUC DL Band AMC Burst Allocation in Other BS IE () = 0x0C Length CID DIUC DIUC used for the burst in the other BS Boosting DL_PermBase Repetition coding indication Type of MAC PDU One 0: same MAC PDU
1: different MAC PDU Frame advance 3bits The number of frames offset from the next frame where the data will be transmitted
(-1 = the current frame, 0 = next frame) OFDMA symbol offset 8bits # OFDMA symbol 7bits Subchannel offset 6bits # subchannels 6bits Reserved 7bits }

The terminal receives and combines or concatenates downlink data transmitted from the anchor base station and the neighboring base station [S44]. That is, when the downlink data transmitted from the anchor base station and the neighboring base station are the same, the terminal combines each received downlink data, and if different, connects the downlink data according to the connection relationship between the downlink data. Information related to whether the downlink data transmitted from the anchor base station and the neighboring base station are the same and the connection relationship between the downlink data is included in the DL MAP transmitted from the anchor base station or the neighboring base station or as separate control information to the terminal. Can be delivered.

Downlink data transmitted from the anchor base station and the neighboring base station may be transmitted through frames of the same view, or different views may be transmitted through the frames. In other words, downlink data to be combined or connected by the terminal may be included in downlink frames transmitted at the same time point from the anchor base station and the neighboring base station, or included in downlink frames transmitted at different time points. . Information related to this should also be included in the DL MAP or transmitted to the terminal as another type of control information.

When both the anchor base station and the neighboring base station use an Automatic Repeat and Request (ARQ) scheme, the terminal may already know the MAC PDU serial number through an ARQ block sequence number. Even if both base stations do not use the ARQ rule, each base station can transmit the serial number of the MAC PDU through the SN extended subheader.

The anchor base station is an enhanced fast feedback channel (enhanced fast feedback channel) enhanced by uplink resources so that the terminal performing the operation according to the band AMC mode can report channel quality information (ex, CQI) for each band periodically or aperiodically. ) Is assigned [S45]. In this case, the anchor base station may allocate uplink resources for reporting channel quality information of the neighboring base station. Allocation of the improved fast feedback channel for reporting channel quality information for the anchor base station and the neighbor base station may be performed by the neighbor base station.

The terminal transmits band-specific channel quality information for the anchor base station and the neighbor base station according to a preset method through an improved fast feedback channel allocated from the anchor base station or the neighbor base station [S46]. For example, the terminal may transmit the CQIs for the top five bands among the CQIs for each band for each of the anchor base station and the neighbor base station as the channel quality information through the improved fast feedback channel. In this case, when a predetermined condition is satisfied, the terminal may change the anchor base station from BS # 1 to BS # 2, and in this case, together with the indication information indicating that the terminal wants to change the anchor base station to BS # 2. Can transmit

When the preset predetermined condition is satisfied, for example, when the band-specific CINR measured for the BS # 1 is smaller than the band-specific CINR measured for the BS # 2, the terminal is connected to the BS # 1. [S47], only the connection with the BS # 2 may be maintained to perform uplink and downlink communication only with the BS # 2. As a result, the handover procedure is terminated.

4 is a flowchart illustrating a method for performing macro diversity handover in a broadband wireless access system according to another embodiment of the present invention, in which a handover procedure is initiated by a base station.

In FIG. 4, the terminal performing an operation according to the band AMC mode receives a MOB_NBR-ADV message including information on neighboring base stations from the serving base station BS # 1 [S51]. The terminal scans the neighbor base stations based on the information about the neighbor base stations included in the MOB_NBR-ADV message [S52]. Since the terminal operates according to the band AMC mode, channel quality, for example, CINR, is measured by performing band-by-band scanning on each neighboring base station instead of the entire band. The terminal transmits a scan result for the neighbor base stations to the serving base station through a MOB_SCN-REP message [S53]. Table 7 shows an example of a format of the MOB_SCN-REP message.

Syntax Size Notes MOB_SCN-REP Message_format () { - Management Message Type = 60 8bits ...... Report metric 8bits Bitmap indicating presence of certain metrics (threshold values) on which the corresponding triggers are based
Bit 0: BS CINR mean
Bit 1: BS RSSI mean
Bit 2: Relative delay
Bit 3: BS RTD; this metric shall be only measured on serving BS / anchor BS
Bit 4: BS CINR per band
Bit 5-7: Reserved For (j = 0; j <N_current_BSs; j ++) { ...... If (Report metric [Bit 4] == 1) NBand For (j = 0; j <NBand; j ++) { BS CINR per band Band bitmap } Band AMC report 32 First 12 bits for indicating band bitmap and 20bits for CINR per best 5 bands ...... For (j = 0 <J <N_Neighbor_BS_Index; j ++) { If (Report metric [Bit 4] == 1) NBand For (j = 0; j <NBand; j ++) { BS CINR per band Band bitmap } Band AMC report 32 First 12 bits for indicating band bitmap and 20bits for CINR per best 5 bands ...... For (j = 0; j <N_Neighbor_BS_Full; j ++) { If (Report metric [Bit 4] == 1) NBand For (j = 0; j <NBand; j ++) { BS CINR per band Band bitmap } Band AMC report 32 First 12 bits for indicating band bitmap and 20bits for CINR per best 5 bands ......

The serving base station BS # 1 determines a handover based on the scan result transmitted from the terminal [S54], and transmits a MOB_BSHO-REQ message with information related to the base stations belonging to the diversity set, anchor base station indication information, and the like. Transmit to the terminal through [S55]. Table 8 shows an example of a format of the MOB_BSHO-REQ message.

Syntax Size Notes MOB_BSHO-REQ Message_format () { - Management Message Type = 56 8bits Network Assisted HO supported 1bits Indicates that the serving BS supports Network Assisted HO Mode 3bits 0b000: HO request
0b001: MDHO / FBSS / MBHO request: Anchor BS update with CID update
0b010: MDHO / FBSS / MBHO request: Anchor BS update without CID update
0b011: MDHO / FBSS / MBHO request: Diversity Set update with CID update
0b100: MDHO / FBSS / MBHO request: Diversity Set update without CID update
0b110: MDHO / FBSS / MBHO request: Diversity Set update with CID update and CQICH allocation for newly added BS
0b111: reserved
......

In FIG. 4, the procedure [S56 ˜ S67] performed after the UE receives the MOB_BSHO-REQ message is the same as S36 ˜ S47 described in FIG. 3. Therefore, detailed description thereof will be omitted.

It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

The present invention has the following effects.

First, a terminal performing an operation in a band AMC mode in a broadband wireless access system can efficiently perform handover.

Second, by performing a macro diversity handover by a terminal performing an operation according to a band AMC mode in a broadband wireless access system, data reception quality can be improved by overcoming an unfavorable channel environment at a cell boundary.

Claims (11)

In the method of performing Macro Diversity Handover (MDHO) in a wireless communication system using a multi-carrier, Channel quality information of at least one subband among a plurality of subbands constituting an entire band is obtained for each anchor base station and a neighbor base station belonging to a diversity set, and the anchor base station and the neighboring base station are provided. Transmitting to at least one of the base stations; Receiving allocation information of each subband selected from the at least one subband for each of the anchor base station and the neighbor base station from any one of the anchor base station and the neighbor base station; Receiving downlink data from any one of each anchor base station and a neighbor base station through each subband allocated through the allocation information; And And terminating the connection with the anchor base station when a preset condition is met. The method according to claim 1, And wherein the at least one subband has the best channel quality among the plurality of subbands. 3. The method of claim 2, Wherein each assigned subband is each subband having the best channel quality among the at least one subband for the anchor base station and the neighbor base station. The method of claim 3, When the subbands having the best channel quality for the anchor base station and the neighbor base station are the same, the channel diversity information, characterized in that for transmitting only the channel quality information for the sub-band to any one of the anchor base station and the neighbor base station. How to do over. The method according to claim 1, And downlink data transmitted through the allocated subbands from the anchor base station and the neighboring base station are the same data. The method according to claim 1, And downlink data transmitted through the allocated subbands from each of the anchor base station and the neighboring base station are unequal data. 6. The method of claim 5, And combining the downlink data transmitted through the allocated subbands from each of the anchor base station and the neighbor base station. The method according to claim 6, And concatenating downlink data transmitted through the allocated subbands from each of the anchor base station and the neighboring base station. The method according to claim 1, Receiving channel allocation information from the anchor base station for feeding back channel quality information for at least one subband for each of the anchor base station and the neighbor base station from the anchor base station; And transmitting channel quality information for at least one subband for each of the anchor base station and the neighbor base station to the anchor base station through the channel indicated by the channel assignment information. . 10. The method of claim 9, When the predetermined condition is satisfied, the channel quality of at least one subband for the neighboring base station is better than the channel quality for at least one subband for the anchor base station, macrodivers, characterized in that How to perform a city handover. A method for performing handover of a terminal performing an operation according to a band AMC mode in a wireless communication system using a multicarrier, Transmitting or receiving uplink or downlink data with a serving base station through a specific subband among a plurality of subbands constituting an entire band; And And performing a handover according to channel quality for each band to establish a connection with a target base station through any one of a plurality of subbands constituting the entire band.

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