`
`rit
`Patentamt
`European
`Patent Office
`desbrevets
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`" "
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`(12)
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`Hl | || || | || | || || | || || || ll
`(11)
`EP 2 427 028 A1
`
`EUROPEAN PATENT APPLICATION
`published in accordance with Art. 153(4) EPC
`
`(43) Date of publication:
`07.03.2012 Bulletin 2012/10
`
`(51) Int Cl:
`HO4W 88/08(2909.01)
`
`HOAW 72/04 (2009.01)
`
`(86) International application number:
`PCT/JP2010/002861
`
`(87) International publication number:
`WO 2010/125769 (04.11.2010 Gazette 2010/44)
`
`* MOCHIZUKI, Mitsuru
`Tokyo 100-8310 (JP)
`¢ SAEGUSA,Taiga
`Tokyo 100-8310 (JP)
`IWANE, Yasushi
`Tokyo 100-8310 (JP)
`
`*
`
`(74) Representative: Sajda, Wolf E. et al
`Meissner, Bolte & Partner GbR
`Postfach 86 06 24
`
`81633 Miinchen (DE)
`
`(21) Application number: 10769470.5
`
`(22) Dateoffiling: 21.04.2010
`
`
`
`(84) Designated Contracting States:
`AT BE BG CH CY CZ DE DK EE ES FI FRGB GR
`HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL
`PT RO SE SISK SM TR
`
`(30) Priority: 28.04.2009 JP 2009109310
`19.06.2009 JP 2009146293
`02.04.2010 JP 2010086194
`
`(71) Applicant: Mitsubishi Electric Corporation
`Tokyo 100-8310 (JP)
`
`(72) Inventors:
`¢ MAEDA, Miho
`Tokyo 100-8310 (JP)
`
`(54)
`
`MOBILE COMMUNICATION SYSTEM
`
`A basestation which useseither one of a plu-
`(57)
`rality of component carriers individually or uses an ag-
`gregate carrier which is an aggregate of the above-men-
`tioned plurality of component carriers to carry out radio
`communications with a mobile terminal corresponding to
`the above-mentioned component carrier and also carry
`out radio communications with a mobile terminal corre-
`
`sponding to the above-mentioned aggregate carrier is
`provided. The base station notifies a bandwidth of an
`aggregate carrier which is an aggregate of all of the
`above-mentioned component carriers, as a bandwidth
`which the above-mentioned basestation uses, to the mo-
`bile terminal corresponding to the above-mentioned ag-
`gregate carrier. As a result, while an improvement in the
`transmission rate is provided according to the aggregate
`carrier, the base station can also support an operation
`of a mobile terminal corresponding to a component car-
`rier.
`
`EP2427028A1
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`TOOMHz
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`Printed by Jouve, 75001 PARIS (FR)
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`FIG.13
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`EP 2 427 028 A1
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`Description
`
`Field of the Invention
`
`[0001] The present invention relates to a base station
`that carries out radio communications with a plurality of
`mobile terminals.
`
`Background of the Invention
`
`[0002] Commercial service of a wideband code divi-
`sion multiple access (W-CDMA) system among so-called
`third-generation communication systems has been of-
`fered in Japan since 2001. In addition, high speed down
`link packet access (HSDPA)service for achieving higher-
`speed data transmission using a down link has been of-
`fered by adding a channel for packet transmission high
`speed-downlink shared channel
`(HS-DSCH))
`to the
`down link (dedicated data channel, dedicated control
`channel). Further, in order to increase the speed of data
`transmission in an uplink direction, service of a high
`speed up link packet access (HSUPA) has been offered.
`W-CDMA is a communication system defined by the 3rd
`generation partnership project (3GPP) thatis the stand-
`ard organization regarding the mobile communication
`system, where the specifications of Release 8 version
`are produced.
`[0003]
`Further, 3GPP is investigating new communi-
`cation systemsreferred to as "long term evolution (LTE)"
`regarding radio areas and "system architecture evolution
`(SAE)" regarding the overall system configuration includ-
`ing acore network (merely referred to as network as well)
`as communication systems independent of W-CDMA.In
`the LTE, an access scheme, radio channel configuration
`and a protocol are totally different from those of the cur-
`rent W-CDMA (HSDPA/HSUPA). For example, as to the
`access scheme, code division multiple accessis used in
`the W-CDMA,whereasin the LTE, orthogonal frequency
`division multiplexing (OFDM) is used in a downlink direc-
`tion and single career frequencydivision multiple access
`(SC-FDMA)is usedin an uplink direction. In addition, the
`bandwidth is 5 MHz in the W-CDMA,while in the LTE,
`the bandwidth can be selected from 1.4 MHz, 3 MHz, 5
`MHz, 10 MHz, 15 MHz and 20 MHz for each basestation.
`Further, differently from the W-CDMA,circuit switching
`is not provided, but rather a packet communication sys-
`tem is provided in the LTE.
`[0004] The LTE is defined as a radio access network
`independent of the W-CDMA network because its com-
`munication system is configured with a new core network
`different from a core network (GPRS) of the W-CDMA.
`Therefore, for differentiation from the W-CDMA commu-
`nication system, a base station that communicates with
`a user equipment (UE) and a radio network controller
`that transmits/receives control data and user data to/from
`
`a plurality of base stations are referred to as an E-UTRAN
`NodeB (eNB) and an evolved packet core (EPC: also
`referred to as access gateway (aGVWV)), respectively, in
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`the LTE communication system. Unicast service and
`evolved multimedia broadcast multicast service (E-
`MBMS service) are provided in this LTE communication
`system. The E-MBMS service is broadcast multimedia
`service, which is merely referred to as MBMS in some
`cases. Bulk broadcast contents such as news, weather
`forecast and mobile broadcast are transmitted to a plu-
`rality of UEs. This is also referred to as point to multipoint
`service.
`
`[0005] Non-Patent Document 1 describes the current
`decisions by 3GPP regarding an overall architecture in
`the LTE system. The overall architecture (Chapter 4 of
`Non-Patent Document 1) is described with reference to
`FIG. 1. FIG. 1
`is a diagram illustrating the configuration
`of the LTE communication system. With reference to FIG.
`1,
`the evolved universal
`terrestrial radio access (E-
`UTRAN) is composedof one ora plurality of base stations
`102, provided that a control protocol (for example, radio
`resource management (RRC)) and a user plane (for ex-
`ample, packet data convergence protocol (PDCP), radio
`link control (RLC), medium access control (MAC), and
`physical layer (PHY)) for a UE 101 are terminated in the
`base station 102. The base stations 102 perform sched-
`uling and transmission of paging signaling (also referred
`to as paging messages) notified from a mobility manage-
`ment entity (MME) 103. The base stations 102 are con-
`nected to each other by means of an X2 interface.
`In
`addition, the base stations 102 are connected to an
`evolved packet core (EPC) by means of an $1 interface,
`more specifically, connected to the mobility management
`entity (MME) 103 by means of an 81_MME interface and
`connected to a serving gateway (S-GW) 104 by means
`of an $1_U interface. The MME 103 distributes the pag-
`ing signaling to multiple or a single base station 102. In
`addition, the MME 103 performs mobility control of an
`idle state. When the UE is in the idle state and an active
`
`state, the MME 103 managesa list of tracking areas. The
`S-GW 104 transmits/receives userdata to/from one ora
`
`plurality of base stations 102. The S-GW 104 serves as
`a local mobility anchor point in handover between base
`stations. Moreover, there is provided a PDN gateway (P-
`GW), which performs per-user packetfiltering and UE-
`ID addressallocation.
`
`[0006] The current decisions by 3GPP regarding the
`frame configuration in the LTE system are describedin
`Non-Patent Document
`1
`(Chapter 5), which are de-
`scribed with reference to FIG. 2. FIG. 2 is a diagram il-
`lustrating the configuration of a radio frame usedin the
`LTE communication system. With reference to FIG. 2,
`one radio frame is 10 ms. The radio frameis divided into
`
`ten equally sized sub-frames. The subframe is divided
`into two equally sized slots. The first and sixth subframes
`contain a downlink synchronization signal (SS) per each
`radio frame. The synchronization signals are classified
`into a primary synchronization signal (P-SS) and a sec-
`ondary synchronization signal (S-SS). Multiplexing of
`channels for multimedia broadcast multicast service sin-
`
`gle frequency network (MBSFN) and for non-MBSFN is
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`EP 2 427 028 A1
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`4
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`performed on a per-subframe basis. Hereinafter, a sub-
`frame for MBSFN transmission is referred to as an MBS-
`
`FN sub-frame. Non-Patent Document 2 describes a sig-
`naling example when MBSFN subframesare allocated.
`FIG. 3 is a diagram illustrating the configuration of the
`MBSFEN frame. With reference to FIG. 3, the MBSFN sub-
`frames are allocated for each MBSFN frame. An MBSFN
`
`frame cluster is scheduled. A repetition period of the
`MBSFN frameclusteris allocated.
`
`[0007] Non-Patent Document 1 describes the current
`decisions by 3GPP regarding the channel configuration
`inthe LTE system. It is assumed that the same channel
`configuration is used in a closed subscriber group (CSG)
`cell as that of anon-CSGcell. A physical channel (Chap-
`ter 5 of Non-Patent Document1) is described with refer-
`ence to FIG. 4. FIG. 4 is a diagram illustrating physical
`channels used in the LTE communication system. With
`reference to FIG. 4, a physical broadcast channel 401
`(PBCH) is a downlink channel transmitted from the base
`station 102 to the UE 101. A BCH transport block is
`mapped to four subframes within a 40 ms interval. There
`is no explicit signaling indicating 40 ms timing. A physical
`control format indicator channel 402 (PCFICH) is for
`transmission from the base station 102 to the UE 101.
`
`The PCFICH notifies the number of OFDM symbols used
`for PDCCHs from the base station 102 to the UE 101.
`
`The PCFICH is transmitted in each subframe. A physical
`downlink control channel 403 (PDCCH) is a downlink
`channel transmitted from the basestation 102 to the UE
`
`101. The PDCCH notifies the resource allocation, HARQ
`information related to DL-SCH (downlink shared channel
`that is one of the transport channels shownin FIG. 5)
`and the PCH (paging channel that is one of the transport
`channels shownin FIG. 5). The PDCCH carries an uplink
`scheduling grant. The PDCCH carries ACK/Nackthatis
`a responsesignal to uplink transmission. The PDCCH is
`referred to as an L1/L2 control signal as well. A physical
`downlink shared channel 404 (PDSCH) is a downlink
`channel transmitted from the base station 102 to the UE
`
`101. A DL-SCH (downlink shared channel) thatis a trans-
`port channel and a PCH thatis a transport channel are
`mapped to the PDSCH. A physical multicast channel 405
`(PMCH) is a downlink channel transmitted from the base
`station 102 to the UE 101. A multicast channel (MCH)
`that is a transport channel is mapped to the PMCH.
`[0008] Aphysical uplink control channel 406 (PUCCH)
`is an uplink channel transmitted from the UE 101 to the
`base station 102. The PUCCH carries ACK/Nackthatis
`
`a responsesignal to downlink transmission. The PUCCH
`carries a channel quality indicator (CQI) report. The CQI
`is quality information indicating the quality of received
`data or channel quality. In addition, the PUCCH carries
`a scheduling request (SR). A physical uplink shared
`channel 407 (PUSCH) is an uplink channel transmitted
`from the UE 101 to the base station 102. A UL-SCH (up-
`link shared channel that is one of the transport channels
`shownin FIG. 5) is mapped to the PUSCH. A physical
`hybrid ARQ indicator channel 408 (PHICH) is a downlink
`
`channel transmitted from the base station 102 to the UE
`
`101. The PHICH carries ACK/Nackthat is a response to
`uplink transmission. A physical random access channel
`409 (PRACH) is an uplink channel transmitted from the
`UE 101 to the base station 102. The PRACH carries a
`
`random access preamble.
`[0009] A downlink reference signal which is a known
`symbol in a mobile communication system is inserted in
`the first, third and last OFDM symbols of each slot. The
`physical layer measurement objects of a UE include, for
`example, reference symbol received power (RSRP).
`[0010] Thetransport channel (Chapter 5 of Non-Patent
`Document 1) is described with reference to FIG. 5. FIG.
`5 is a diagram illustrating transport channels usedin the
`LTE communication system. FIG. 5(A) shows mapping
`between a downlink transport channel and a downlink
`physical channel. FIG. 5(B) shows mapping between an
`uplink transport channel and an uplink physical channel.
`A broadcast channel (BCH) is broadcast to the entire
`coverage of the base station (cell) regarding the downlink
`transport channel. The BCH is mappedto the physical
`broadcast channel (PBCH). Retransmission control ac-
`cording to a hybrid ARQ (HARQ)is applied to a downlink
`shared channel (DL-SCH). Broadcastto the entire cov-
`erage of the base station (cell) is enabled. The DL-SCH
`supports dynamic or semi-static resource allocation. The
`semi-static resource allocation is also referred to as per-
`sistent scheduling. The DL-SCH supports discontinuous
`reception (DRX) of a UE for enabling the UE to save
`power. The DL-SCH is mappedto the physical downlink
`shared channel (PDSCH). The paging channel (PCH)
`supports DRX of the UE for enabling the UE to save pow-
`er. Broadcast to the entire coverage of the base station
`(cell) is required. The PCH is mapped to physical resourc-
`es such as the physical downlink shared channel (PD-
`SCH) that can be used dynamically for traffic or physical
`resources such as the physical downlink control channel
`(PDCCH) of the other control channel. The multicast
`channel (MCH) is used for broadcastto the entire cov-
`erage of the basestation (cell). The MCH supports SFN
`combining of MBMS service (MTCH and MCCH) in multi-
`cell
`transmission. The MCH supports semi-static re-
`source allocation. The MCH is mapped to the PMCH.
`[0011] Retransmission control according to a hybrid
`ARQ (HARQ) is applied to an uplink shared channel (UL-
`SCH). The UL-SCH supports dynamic or semi-static re-
`source allocation. The UL-SCH is mapped to the physical
`uplink shared channel (PUSCH). Arandom access chan-
`nel (RACH) shownin FIG. 5(B) is limited to control infor-
`mation. There is a collision risk. The RACH is mapped
`to the physical random access channel (PRACH). The
`HAR@Qis described.
`
`[0012] The HARQis the technique for improving the
`communication quality of a channel by combination of
`automatic repeat request and forward error correction.
`The HARQhasan advantage that error correction func-
`tions effectively by retransmission even for a channel
`whose communication quality changes. In particular,it
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`EP 2 427 028 A1
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`is also possible to achieve further quality improvement
`in retransmission through combination of the reception
`results of the first transmission and the reception results
`of the retransmission. An example of the retransmission
`method is described. In a case where the receiver fails
`
`to successfully decode the received data (ina case where
`a
`cyclic
`redundancy check (CRC)
`error occurs
`(CRC=NG)), the receiver transmits "Nack" to the trans-
`mitter. The transmitter that has received "Nack"retrans-
`
`mits the data. In a case where the receiver successfully
`decodesthe received data (in a case where a CRCerror
`does not occur (CRC=Ok)), the receiver transmits "Ack"
`to the transmitter. The transmitter that has received "Ack"
`
`transmits the next data. Examples of the HARQ system
`include "chase combining".
`In chase combining,
`the
`same data sequenceis transmitted in the first transmis-
`sion and retransmission, which is the system for improv-
`ing gains by combining the data sequence of the first
`transmission and the data sequenceof the retransmis-
`sion. This is based on the idea that correctdatais partially
`included even if the data ofthe first transmission contains
`
`an error, and highly accurate data transmission is ena-
`bled by combining the correct portions ofthe first trans-
`mission data and the retransmission data. Another ex-
`
`ample of the HARQ system is incremental redundancy
`(IR). The IR is aimed to increase redundancy, where a
`parity bit is transmitted in retransmission to increase the
`redundancy by combining the first transmission and re-
`transmission, to thereby improve the quality by an error
`correction function.
`
`[0013] A logical channel (Chapter 6 of Non-Patent
`Document 1) is described with reference to FIG. 6. FIG.
`6 is adiagram illustrating logical channels used in an LTE
`communication system. FIG. 6(A) shows mapping be-
`tween a downlink logical channel and a downlink trans-
`port channel. FIG. 6(B) shows mapping between an up-
`link logical channel and an uplink transport channel. A
`broadcast control channel (BCCH) is a downlink channel
`for broadcast system control information. The BCCH that
`is a logical channel is mappedto the broadcast channel
`(BCH) or downlink shared channel (DL-SCH) that is a
`transport channel. A paging control channel (PCCH) is
`a downlink channel for transmitting paging signals. The
`PCCH is used when the network does not knowthe cell
`
`location of a UE. The PCCH thatis a logical channel is
`mappedto the paging channel (PCH) which is a transport
`channel. Acommeon control channel (CCCH) is achannel
`for transmission control information between UEs anda
`base station. The CCCH is used in a case where the UEs
`have no RRC connection with the base station. In down-
`
`link, the CCCH is mapped to the downlink shared channel
`(DL-SCH) which is a transport channel.
`In uplink, the
`CCCH is mappedto the uplink shared channel (UL-SCH)
`whichis a transport channel.
`[0014] A multicast control channel (MCCH) is a down-
`link channel for point-to-multipoint transmission. The
`MCCH is a channel used for transmission of MBMS con-
`trol information for one or several MTCHs from a network
`
`toa UE. The MCCH is achannel used only by a UE during
`reception of the MBMS. The MCCH is mapped to the
`downlink shared channel (DL-SCH) or multicast channel
`(MCH) which is a transport channel. A dedicated control
`channel (DCCH) is a channel that transmits dedicated
`control information between a UE and a network. The
`
`DCCH is mappedto the uplink shared channel (UL-SCH)
`in uplink and mapped to the downlink shared channel
`(DL-SCH) in downlink. A dedicate traffic channel (DTCH)
`is a point-to-point communication channel for transmis-
`sion of user information to a dedicated UE. The DTCH
`
`exists in uplink as well as downlink. The DTCH is mapped
`to the uplink shared channel (UL-SCH) in uplink and
`mapped to the downlink shared channel (DL-SCH) in
`downlink. A multicast traffic channel (MTCH) is a down-
`link channel for traffic data transmission from a network
`
`toa UE. The MTCH isa channel used only by a UE during
`reception of the MBMS. The MTCH is mapped to the
`downlink shared channel (DL-SCH) or multicast channel
`(MCR).
`[0015] GCl represents a global cell identity. A closed
`subscriber group (CSG) cell is introduced in the LTE and
`universal mobile telecommunication system (UMTS).
`The CSG is described below (Chapter 3.1 of Non-Patent
`Document 4). The closed subscriber group (CSG) is a
`cell in which subscribers who are permitted to use are
`identified by an operator(cell for identified subscribers).
`The identified subscribers are permitted to access one
`or more E-UTRANcells of a public land mobile network
`(PLMN). One or more E-UTRANcells in which the iden-
`tified subscribers are permitted to access are referred to
`as "CSG cell(s)". Note that accessis limited in the PLMN.
`The CSG cell is part of the PLMN that broadcasts a spe-
`cific CSG identity (CSG ID, CSG-ID). The members of
`the authorized subscriber group who haveregisteredin
`advance access the CSG cells using the CSG-ID thatis
`the access permission information. The CSG-ID is broad-
`cast by the CSG cell or cells. A plurality of CSG-IDs exist
`in a mobile communication system. The CSG-IDs are
`used by UEsfor making access from CSG-related mem-
`bers easy. 3GPP discusses in a meeting that the infor-
`mation to be broadcastby the CSG cell or cells is changed
`from the CSG-ID to a tracking area code (TAC). The lo-
`cations of UEs are traced based on an area composed
`of one or more cells. The locations are traced for enabling
`tracing of the locations of UEs and calling (calling of UEs)
`even in an idle state. An area for tracing locations of UEs
`is referred to as a tracking area. A CSG whitelist is a list
`stored in the USIM containing all the CSG IDs of the CSG
`cells to which the subscribers belong. The whitelist of the
`UE is provided by a higher layer. By means ofthis, the
`basestation of the CSG cell allocates radio resources to
`the UEs.
`
`[0016] A “suitable cell" is described below (Chapter 4.
`3 of Non-Patent Document 4). The "suitable cell" is a cell
`on which a UE campsto obtain normal service. Such a
`cell shall fulfill the following: (1) the cell
`is part of the
`selected PLMN or the registered PLMN, or part of the
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`EP 2 427 028 A1
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`PLMN of an “equivalent PLMN list"; and (2) according to
`the latest information provided by a non-access stratum
`(NAS), the cell shall further fulfill the following conditions:
`(a) the cell is not a barred cell; (b) the cell is part of at
`least one tracking area (TA), not part of "forbidden LAs
`for roaming", where the cell needs tofulfill (1) above; (c)
`the cell shall fulfill the cell selection criteria; and (d) fora
`cell identified as CSG cell by system information (Sl), the
`CSG-ID is part of a "CSG whitelist" of the UE (contained
`in the CSG whitelist of the UE).
`[0017] An “acceptable cell" is described below (Chap-
`ter 4.3 of Non-Patent Document 4). This is the cell on
`which a UE campsto obtain limited service (emergency
`calls). Such a cell shall fulfill all the following require-
`ments. Thatis, the minimum required setforinitiating an
`emergencycall in an E-UTRAN networkare as follows:
`(1) the cell is not a barred cell; and (2) the cell fulfills the
`cell selection criteria.
`
`3GPP is studying base stations referred to as
`[0018]
`Home-NodeB (Home-NB, HNB) and Home-eNodeB
`(Home-eNB, HeNB). HNB/HeNB is a basestation for, for
`example, household, corporation or commercial access
`service in UTRAN/E-UTRAN. Non-Patent Document 6
`discloses three different modes of the access to the
`
`HeNB and HNB. Those are an open access mode, a
`closed access mode and a hybrid access mode. The re-
`spective modeshavethe following characteristics. In the
`open access mode, the HeNB and HNB are operated as
`a normal cell of a normal operator. In the closed access
`mode, the HeNB and HNB are operated as a CSG cell.
`The CSG cell is a cell where only CSG members are
`allowed access. In the hybrid access mode, the HeNB
`and HNB are CSG cells where non-CSG members are
`allowed access at the same time. In other words, a cell
`in the hybrid access mode is the cell that supports both
`the open access mode and the closed access mode.
`
`Related art document
`
`Nonpatent reference
`
`[0019]
`
`Nonpatent reference 1: 3GPP TS36.300 V8.6.0
`Chapters 4, 5, and 6
`Nonpatent reference 2: 3GPP R1-072963
`Nonpatent reference 3: TR R3.020 V0.6.0
`Nonpatent reference 4: 3GPP TS36.304 V8.4.0
`Chapters 3.1, 4.3, 5.2.4.2, 5.2.4.3, 5.2.4.6, 7.1, and
`7.2
`
`Nonpatent reference 5: 3GPP R2-082899
`Nonpatent reference 6: 3GPP S1-083461
`Nonpatent reference 7: TR 36.814 V0.4.1 Chapter 5
`Nonpatent reference 8: 3GPP R1-090860
`Nonpatent reference 9: 3GPP TS36.331 V8.4.0
`Chapter 6.2.2
`Nonpatent reference 10: 3GPP R2-093104
`
`Summaryof the Invention
`
`Problemsto be Solved bythe Invention
`
`It has been considered that in a long term evo-
`[0020]
`lution advanced (Long Term Evolution Advanced: LTE-
`A) system,
`larger frequency bandwidths than the fre-
`quency bandwidths of an LTE system are supported. This
`support is aimed at an improvement in the transmission
`rate. It has been discussedin the 3GPP thatthe frequen-
`cy bandwidth of an LTE-A system is set to 100 MHz or
`less.
`
`[0021] The frequency usage pattern varies from region
`to region. Therefore, there can be a region which cannot
`secure a continuous frequency bandwidth of 100 MHz.
`It has been further considered that a compatible opera-
`tion of an LTE-support mobile terminal is implemented
`inanLTE-Asystem. Inthe 3GPP, it has been considered
`in connection with the compatible operation that a fre-
`quency band (carrier) is divided into elements each re-
`ferred to as a component carrier (component carrier). In
`the 3GPP, it has been planned that an LTE-support mo-
`bile terminal can operate on each of these component
`carriers. It has been further considered that an improve-
`ment is provided in the transmission rate of an LTE-A
`system by using an aggregate carrier which is created
`by aggregating (aggregating) component carriers.
`[0022]
` Itis an objectof the present invention to provide
`a base station which implements an improvement in the
`transmission rate by complying with an aggregate carrier
`a while supporting an operation of a mobile terminal cor-
`responding to component carriers.
`
`Means for Solving the Problem
`
`In accordance with the present invention, there
`[0023]
`is provided a base station which useseither one of a
`plurality of component carriers individually or uses an
`aggregate carrier which is an aggregate of the above-
`mentioned plurality of component carriers to carry out
`radio communications with a mobile terminal corre-
`
`sponding to the above-mentioned component carrier and
`also carry out radio communications with a mobile termi-
`nal corresponding to the above-mentioned aggregate
`carrier, wherein the base station notifies a bandwidth of
`an aggregate carrier which is an aggregate ofall of the
`above-mentioned component carriers, as a bandwidth
`which the above-mentioned base station uses, to the mo-
`bile terminal corresponding to the above-mentioned ag-
`gregate carrier.
`
`Advantagesof the Invention
`
`in accordance with the
`[0024] The mobile terminal
`presentinvention can transmit required information cor-
`rectly by notifying the bandwidth of the aggregate carrier
`which is an aggregate of all of the component carriers
`instead of the bandwidth of any component carrier, as
`
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`EP 2 427 028 A1
`
`10
`
`Fig. 17
`
`Fig. 18
`
`Fig. 19
`
`Fig. 20
`
`Fig. 21
`
`Fig. 22
`
`Fig. 23
`
`Fig. 24
`
`10
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`15
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`20
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`25
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`Fig. 25
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`30
`
`Fig. 26
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`Fig. 27
`
`Fig. 28
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`Fig. 29
`
`ance with Variant 1 of Embodiment 2;
`is a conceptual diagram showing a problem
`shown in Embodiment 3;
`is a flow chart showing an operation of a mo-
`bile terminal showing the problem in Embod-
`iment 3;
`is a flow chart showing an operation of a mo-
`bile terminal in accordance with Embodiment
`3;
`is a sequence diagram showing an operation
`of a mobile communication system in accord-
`ance with Variant 2 of Embodiment 3;
`is a view explaining a first concrete example
`of component carrier information of a neigh-
`boring cellin accordancewith Variant 1 of Em-
`bodiment 4;
`is a view explaining a second concrete exam-
`ple of the componentcarrier information of a
`neighboring cell in accordance with Variant 1
`of Embodiment 4;
`is a view explaining a third concrete example
`of the component carrier information of a
`neighboring cell in accordance with Variant 1
`of Embodiment 4;
`is a view explaining a fourth concrete example
`of the component carrier information of a
`neighboring cell in accordance with Variant 1
`of Embodiment 4;
`is a flow chart showing an operation of a mo-
`bile terminal in accordance with Variant 1 of
`
`Embodiment 4;
`is a flow chart showing an operation of a mo-
`bile terminal in accordance with Variant 2 of
`Embodiment 4;
`is a conceptual diagram showing a solution
`provided by Embodiment 7;
`is a sequence diagram showing an operation
`of a mobile communication system in accord-
`ance with Embodiment8; and
`is asequence diagram showing the operation
`of the mobile communication system in ac-
`cordance with Embodiment 8.
`
`the bandwidth which the base station uses, to the mobile
`terminal. As a result, while an improvement in the trans-
`mission rate is provided according to the aggregate car-
`rier, the base station can also support an operation of a
`mobile terminal corresponding to a componentcarrier.
`
`Brief Description of the Figures
`
`[0025]
`
`Fig. 1
`
`Fig. 2
`
`Fig. 3
`
`Fig. 4
`
`Fig. 5
`
`Fig. 6
`
`Fig. 7
`
`Fig. 8
`
`Fig. 9
`
`Fig. 10
`
`Fig. 11
`
`Fig. 12
`
`Fig. 13
`
`Fig. 14
`
`Fig. 15
`
`Fig. 16
`
`is an explanatory drawing showing the config-
`uration of a communication system using an
`LTE method;
`is an explanatory drawing showing the config-
`uration of a radio frame for use in a commu-
`
`nication system using an LTE method;
`is an explanatory drawing showing the config-
`uration of an MBSFN (Multimedia Broadcast
`multicast service Single Frequency Network)
`frame;
`is an explanatory drawing explaining physical
`channels for use in a communication system
`using an LTE method;
`is an explanatory drawing explaining the trans-
`port channels for use in a communication sys-
`tem using an LTE method;
`is an explanatory drawing explaining logical
`channels for use in a communication system
`using an LTE method;
`is a block diagram showing the whole structure
`of a mobile communication system which has
`been debated in the 3GPP;
`is a block diagram showing the structure of a
`mobile terminal 311 in accordance with the
`
`presentinvention;
`is a block diagram showing the structure of a
`base station 312 in accordance with the
`
`presentinvention;
`is a block diagram showing the structure of an
`MME in accordance with the present inven-
`tion;
`is a block diagram showing the structure of an
`HeNBGW in accordance with the present in-
`vention;
`is a flow chart showing an outline of a cell
`search made by a mobile terminal (UE) in a
`communication system which supports an
`LTE method;
`is a view showing the configuration of a fre-
`quency band for use in an LTE-A system;
`is a flow chart showing an operation of a mo-
`bile terminal in accordance with Embodiment
`
`1;
`is a sequence diagram showing an operation
`of a mobile communication system in accord-
`ance with Embodiment 2;
`is a sequence diagram showing an operation
`of a mobile communication system in accord-
`
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`Embodiments of the Invention
`
`Embodiment 1
`
`FIG. 7 is a block diagram showing an overall
`[0026]
`configuration of an LTE mobile communication system,
`which is currently under discussion of 3GPP. Currently,
`3GPP is studying an overall system configuration includ-
`ing closed subscriber group (CSG) cells (Home-eNo-
`deBs (Home-eNB and HeNB) of e-UTRAN, Home-NB
`(HNB) of UTRAN) and non-CSG cells (eNodeB (eNB) of
`e-UTRAN, NodeB (NB) of UTRAN, and BSS of GERAN)
`and, as to e-UTRAN, is proposing the configurations of
`(a) and (b) of FIG. 7 (Non-Patent Document 1 and Non-
`Patent Document 3). FIG. 7(a) is now described. A user
`
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`

`11
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`EP 2 427 028 A1
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`12
`
`equipment (UE) 71 performs transmission/reception to/
`from a basestation 72. The base station 72 is classified
`
`into an eNB (non-CSG cell) 72-1 and Home-eNBs (CSG
`cells) 72-2. The eNB 72-1 is connected to MMEs 73
`through interfaces $1, and control information is commu-
`nicated between the eNB and the MMEs. A plurality of
`MMEsare connected to one eNB. The Home-eNB 72-2
`
`is connected to the MME 73 through the interface $1,
`and control
`information is communicated between the
`
`Home-eNB and the MME. A plurality of Home-eNBs are
`connected to one MME.
`
`[0027] Next, FIG. 7(b) is described. The UE 71 per-
`forms transmission/reception to/from the base station 72.
`The basestation 72 is classified into the eNB (non-CSG
`cell) 72-1 and the Home-eNBs (CSG cells) 72-2. As in
`FIG. 7(a), the eNB 72-1 is connected to the MMEs 73
`through the interface $1, and control information is com-
`municated between the eNB and the MMEs. A plurality
`of MMEsare connected to one eNB. While, the Home-
`eNBs 72-2 are connected to the MMEs 73 through a
`Home-eNB Gateway (HeNBGW) 74. The Home-eNBs
`are connected to the HeGW through the interfaces $1,
`and the HeNBGW 74 is connected to the MMEs 73
`
`through an interface S1_flex. One ora plurality of Home-
`eNBs 72-2 are connected to one HeNBGW 74, and in-
`formation is communicated therebetween through $1.
`The HeNBGW 74 is connected to one ora plurality of
`MMEs 73, and information is communicated therebe-
`tween through $1_flex.
`[0028] With the configuration of FIG. 7(b), one HeNB-
`GW 74 is connected to the Home-eNBsbelonging to the
`same CSG-ID. As a result, in the case where the same
`information such as registration information is transmit-
`ted from the MME 73 to a plurality of Home-eNBs 72-2
`belonging to the same CSG-ID, the information is trans-
`mitted to the HeNBGW 74 and then transmitted to the
`
`plurality of Home-eNBs 72-2, with the result that signaling
`efficiency is enhanced more compared with the case
`wherethe information is directly transmitted to each of
`the plurality of Home-eNBs 72-2. While, inthe case where
`each Home-eNB 72-2 communicates dedicated informa-
`
`tion with the MME 73, the information is merely caused
`to pass through the HeNBGW 74(to be transparent) with-
`out being processed, which allows communication in
`such a mannerthat the Home-eNB 72-2 is directly con-
`nec